WorldWideScience

Sample records for ccd cameras exposed

  1. CCD Camera

    Science.gov (United States)

    Roth, Roger R.

    1983-01-01

    A CCD camera capable of observing a moving object which has varying intensities of radiation eminating therefrom and which may move at varying speeds is shown wherein there is substantially no overlapping of successive images and wherein the exposure times and scan times may be varied independently of each other.

  2. Modeling of the over-exposed pixel area of CCD cameras caused by laser dazzling

    Science.gov (United States)

    Benoist, Koen W.; Schleijpen, Ric H. M. A.

    2014-10-01

    A simple model has been developed and implemented in Matlab code, predicting the over-exposed pixel area of cameras caused by laser dazzling. Inputs of this model are the laser irradiance on the front optics of the camera, the Point Spread Function (PSF) of the used optics, the integration time of the camera, and camera sensor specifications like pixel size, quantum efficiency and full well capacity. Effects of the read-out circuit of the camera are not incorporated. The model was evaluated with laser dazzle experiments on CCD cameras using a 532 nm CW laser dazzler and shows good agreement. For relatively low laser irradiance the model predicts the over-exposed laser spot area quite accurately and shows the cube root dependency of spot diameter on laser irradiance, caused by the PSF as demonstrated before for IR cameras. For higher laser power levels the laser induced spot diameter increases more rapidly than predicted, which probably can be attributed to scatter effects in the camera. Some first attempts to model scatter contributions, using a simple scatter power function f(θ), show good resemblance with experiments. Using this model, a tool is available which can assess the performance of observation sensor systems while being subjected to laser countermeasures.

  3. CCD Luminescence Camera

    Science.gov (United States)

    Janesick, James R.; Elliott, Tom

    1987-01-01

    New diagnostic tool used to understand performance and failures of microelectronic devices. Microscope integrated to low-noise charge-coupled-device (CCD) camera to produce new instrument for analyzing performance and failures of microelectronics devices that emit infrared light during operation. CCD camera also used to indentify very clearly parts that have failed where luminescence typically found.

  4. Advanced CCD camera developments

    Energy Technology Data Exchange (ETDEWEB)

    Condor, A. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    Two charge coupled device (CCD) camera systems are introduced and discussed, describing briefly the hardware involved, and the data obtained in their various applications. The Advanced Development Group Defense Sciences Engineering Division has been actively designing, manufacturing, fielding state-of-the-art CCD camera systems for over a decade. These systems were originally developed for the nuclear test program to record data from underground nuclear tests. Today, new and interesting application for these systems have surfaced and development is continuing in the area of advanced CCD camera systems, with the new CCD camera that will allow experimenters to replace film for x-ray imaging at the JANUS, USP, and NOVA laser facilities.

  5. Transmission electron microscope CCD camera

    Science.gov (United States)

    Downing, Kenneth H.

    1999-01-01

    In order to improve the performance of a CCD camera on a high voltage electron microscope, an electron decelerator is inserted between the microscope column and the CCD. This arrangement optimizes the interaction of the electron beam with the scintillator of the CCD camera while retaining optimization of the microscope optics and of the interaction of the beam with the specimen. Changing the electron beam energy between the specimen and camera allows both to be optimized.

  6. Vacuum compatible miniature CCD camera head

    Science.gov (United States)

    Conder, Alan D.

    2000-01-01

    A charge-coupled device (CCD) camera head which can replace film for digital imaging of visible light, ultraviolet radiation, and soft to penetrating x-rays, such as within a target chamber where laser produced plasmas are studied. The camera head is small, capable of operating both in and out of a vacuum environment, and is versatile. The CCD camera head uses PC boards with an internal heat sink connected to the chassis for heat dissipation, which allows for close(0.04" for example) stacking of the PC boards. Integration of this CCD camera head into existing instrumentation provides a substantial enhancement of diagnostic capabilities for studying high energy density plasmas, for a variety of military industrial, and medical imaging applications.

  7. CCD characterization for a range of color cameras

    NARCIS (Netherlands)

    Withagen, P.J.; Groen, F.C.A.; Schutte, K.

    2005-01-01

    CCD cameras are widely used for remote sensing and image processing applications. However, most cameras are produced to create nice images, not to do accurate measurements. Post processing operations such as gamma adjustment and automatic gain control are incorporated in the camera. When a (CCD) cam

  8. A comparison of colour micrographs obtained with a charged couple devise (CCD) camera and a 35-mm camera

    DEFF Research Database (Denmark)

    Pedersen, Mads Møller; Smedegaard, Jesper; Jensen, Peter Koch;

    2005-01-01

    ophthalmology, colour CCD camera, colour film, digital imaging, resolution, micrographs, histopathology, light microscopy......ophthalmology, colour CCD camera, colour film, digital imaging, resolution, micrographs, histopathology, light microscopy...

  9. Mid-IR image acquisition using a standard CCD camera

    DEFF Research Database (Denmark)

    Dam, Jeppe Seidelin; Sørensen, Knud Palmelund; Pedersen, Christian;

    2010-01-01

    Direct image acquisition in the 3-5 µm range is realized using a standard CCD camera and a wavelength up-converter unit. The converter unit transfers the image information to the NIR range were state-of-the-art cameras exist.......Direct image acquisition in the 3-5 µm range is realized using a standard CCD camera and a wavelength up-converter unit. The converter unit transfers the image information to the NIR range were state-of-the-art cameras exist....

  10. BUNDLE ADJUSTMENTS CCD CAMERA CALIBRATION BASED ON COLLINEARITY EQUATION

    Institute of Scientific and Technical Information of China (English)

    Liu Changying; Yu Zhijing; Che Rensheng; Ye Dong; Huang Qingcheng; Yang Dingning

    2004-01-01

    The solid template CCD camera calibration method of bundle adjustments based on collinearity equation is presented considering the characteristics of space large-dimension on-line measurement. In the method, a more comprehensive camera model is adopted which is based on the pinhole model extended with distortions corrections. In the process of calibration, calibration precision is improved by imaging at different locations in the whole measurement space, multi-imaging at the same location and bundle adjustments optimization. The calibration experiment proves that the calibration method is able to fulfill calibration requirement of CCD camera applied to vision measurement.

  11. Printed circuit board for a CCD camera head

    Science.gov (United States)

    Conder, Alan D.

    2002-01-01

    A charge-coupled device (CCD) camera head which can replace film for digital imaging of visible light, ultraviolet radiation, and soft to penetrating x-rays, such as within a target chamber where laser produced plasmas are studied. The camera head is small, capable of operating both in and out of a vacuum environment, and is versatile. The CCD camera head uses PC boards with an internal heat sink connected to the chassis for heat dissipation, which allows for close (0.04" for example) stacking of the PC boards. Integration of this CCD camera head into existing instrumentation provides a substantial enhancement of diagnostic capabilities for studying high energy density plasmas, for a variety of military industrial, and medical imaging applications.

  12. CCD Color Camera Characterization for Image Measurements

    NARCIS (Netherlands)

    Withagen, P.J.; Groen, F.C.A.; Schutte, K.

    2007-01-01

    In this article, we will analyze a range of different types of cameras for its use in measurements. We verify a general model of a charged coupled device camera using experiments. This model includes gain and offset, additive and multiplicative noise, and gamma correction. It is shown that for sever

  13. Linear array CCD sensor for multispectral camera

    Science.gov (United States)

    Chabbal, J.; Boucharlat, G.; Capppechi, F.; Benoit-Gonin, R.

    1985-10-01

    Design, operational and performance features are described for a new 2048 element CCD array in a ceramic package for beam sharing focal plane arrangements on remote sensing satellites. The device, labeled the TH 7805, furnishes 13 micron square pixels at 13 microns pitch over the 480-930 nm interval, two video outputs and a single-phase, buried channel CCD register. Each n-p photodiode is linked to a Si coating by a gate storing the photocharges. Crosstalk between elements is less than 1 percent and the rms noise level is 180 micro-V. The array output sensitivity is 1.37 micro-V/electron, linearity to less than 1 percent, and a 10 MHz maximum data rate. The entire sensor package draws under 150 mW power from the spacecraft. The TH 7805 has withstood over 10 krads in tests without exhibiting faults.

  14. A luminescence imaging system based on a CCD camera

    DEFF Research Database (Denmark)

    Duller, G.A.T.; Bøtter-Jensen, L.; Markey, B.G.

    1997-01-01

    to photographic systems, in order to obtain spatially resolved data. However, the former option is extremely expensive and it is difficult to obtain quantitative data from the latter. This paper describes the use of a CCD camera for imaging both thermoluminescence and optically stimulated luminescence. The system...... described here has a maximum spatial resolution of 17 mu m; though this may be varied under software control to alter the signal-to-noise ratio. The camera has been mounted on a Riso automated TL/OSL reader, and both the reader and the CCD are under computer control. In the near u.v and blue part...

  15. A new method to evaluate imaging quality of CCD cameras

    Institute of Scientific and Technical Information of China (English)

    LI Wen-juan; DU Hai-hui; DAI Jing-min; CHEN Ying-hang

    2005-01-01

    In order to evaluate the imaging quality of CCD cameras fully and rapidly,the minimum resolvable contrast (MRC) is presented in this paper and the system of measuring MRC is constructed as well,in which two integrating spheres are proposed to illuminate two sides of the target respectively.The variable contrast can be obtained by regulating the luminance of integrating spheres. Experimental results indicate that the error of measuring luminance is within ±0.3 cd/m2,MRC rises with the increase of the spatial frequency.The experimental results show that the method proposed is an effective approach to evaluate the imaging quality of CCD cameras.

  16. Visual enhancement of laparoscopic nephrectomies using the 3-CCD camera

    Science.gov (United States)

    Crane, Nicole J.; Kansal, Neil S.; Dhanani, Nadeem; Alemozaffar, Mehrdad; Kirk, Allan D.; Pinto, Peter A.; Elster, Eric A.; Huffman, Scott W.; Levin, Ira W.

    2006-02-01

    Many surgical techniques are currently shifting from the more conventional, open approach towards minimally invasive laparoscopic procedures. Laparoscopy results in smaller incisions, potentially leading to less postoperative pain and more rapid recoveries . One key disadvantage of laparoscopic surgery is the loss of three-dimensional assessment of organs and tissue perfusion. Advances in laparoscopic technology include high-definition monitors for improved visualization and upgraded single charge coupled device (CCD) detectors to 3-CCD cameras, to provide a larger, more sensitive color palette to increase the perception of detail. In this discussion, we further advance existing laparoscopic technology to create greater enhancement of images obtained during radical and partial nephrectomies in which the assessment of tissue perfusion is crucial but limited with current 3-CCD cameras. By separating the signals received by each CCD in the 3-CCD camera and by introducing a straight forward algorithm, rapid differentiation of renal vessels and perfusion is accomplished and could be performed real time. The newly acquired images are overlaid onto conventional images for reference and comparison. This affords the surgeon the ability to accurately detect changes in tissue oxygenation despite inherent limitations of the visible light image. Such additional capability should impact procedures in which visual assessment of organ vitality is critical.

  17. A New Technique for CCD Camera Auto-Calibration

    Institute of Scientific and Technical Information of China (English)

    Xiaodong Zhang; Changku Sun; Zhixiong Wang; Wei Wei

    2003-01-01

    A novel feature-round-based coplanar drone for the CCD camera auto-calibration is designed. Based on the ellipse similarity, an ellipse recognition algorithm is proposed. The experiment indicates the calibration error is less than 0.4 pixel.

  18. The development of large-aperture test system of infrared camera and visible CCD camera

    Science.gov (United States)

    Li, Yingwen; Geng, Anbing; Wang, Bo; Wang, Haitao; Wu, Yanying

    2015-10-01

    Infrared camera and CCD camera dual-band imaging system is used in many equipment and application widely. If it is tested using the traditional infrared camera test system and visible CCD test system, 2 times of installation and alignment are needed in the test procedure. The large-aperture test system of infrared camera and visible CCD camera uses the common large-aperture reflection collimator, target wheel, frame-grabber, computer which reduces the cost and the time of installation and alignment. Multiple-frame averaging algorithm is used to reduce the influence of random noise. Athermal optical design is adopted to reduce the change of focal length location change of collimator when the environmental temperature is changing, and the image quality of the collimator of large field of view and test accuracy are also improved. Its performance is the same as that of the exotic congener and is much cheaper. It will have a good market.

  19. Design and application of TEC controller Using in CCD camera

    Science.gov (United States)

    Gan, Yu-quan; Ge, Wei; Qiao, Wei-dong; Lu, Di; Lv, Juan

    2011-08-01

    Thermoelectric cooler (TEC) is a kind of solid hot pump performed with Peltier effect. And it is small, light and noiseless. The cooling quantity is proportional to the TEC working current when the temperature difference between the hot side and the cold side keeps stable. The heating quantity and cooling quantity can be controlled by changing the value and direction of current of two sides of TEC. So, thermoelectric cooling technology is the best way to cool CCD device. The E2V's scientific image sensor CCD47-20 integrates TEC and CCD together. This package makes easier of electrical design. Software and hardware system of TEC controller are designed with CCD47-20 which is packaged with integral solid-state Peltier cooler. For hardware system, 80C51 MCU is used as CPU, 8-bit ADC and 8-bit DAC compose of closed-loop controlled system. Controlled quantity can be computed by sampling the temperature from thermistor in CCD. TEC is drove by MOSFET which consists of constant current driving circuit. For software system, advanced controlled precision and convergence speed of TEC system can be gotten by using PID controlled algorithm and tuning proportional, integral and differential coefficient. The result shows: if the heat emission of the hot side of TEC is good enough to keep the temperature stable, and when the sampling frequency is 2 seconds, temperature controlled velocity is 5°C/min. And temperature difference can reach -40°C controlled precision can achieve 0.3°C. When the hot side temperature is stable at °C, CCD temperature can reach -°C, and thermal noise of CCD is less than 1e-/pix/s. The controlled system restricts the dark-current noise of CCD and increases SNR of the camera system.

  20. CCD camera full range pH sensor array.

    Science.gov (United States)

    Safavi, A; Maleki, N; Rostamzadeh, A; Maesum, S

    2007-01-15

    Changes in colors of an array of optical sensors that responds in full pH range were recorded using a CCD camera. The data of the camera were transferred to the computer through a capture card. Simple software was written to read the specific color of each sensor. In order to associate sensor array responses with pH values, a number of different mathematics and chemometrics methods were investigated and compared. The results show that the use of "Microsoft Excel's Solver" provides results which are in very good agreement with those obtained with chemometric methods such as artificial neural network (ANN) and partial least square (PLS) methods. PMID:19071333

  1. Proton radiation damage experiment on P-Channel CCD for an X-ray CCD camera onboard the ASTRO-H satellite

    International Nuclear Information System (INIS)

    We report on a proton radiation damage experiment on P-channel CCD newly developed for an X-ray CCD camera onboard the ASTRO-H satellite. The device was exposed up to 109 protons cm−2 at 6.7 MeV. The charge transfer inefficiency (CTI) was measured as a function of radiation dose. In comparison with the CTI currently measured in the CCD camera onboard the Suzaku satellite for 6 years, we confirmed that the new type of P-channel CCD is radiation tolerant enough for space use. We also confirmed that a charge-injection technique and lowering the operating temperature efficiently work to reduce the CTI for our device. A comparison with other P-channel CCD experiments is also discussed. -- Author-Highlights: •We performed a proton radiation damage experiment on a new P-channel CCD. •The device was exposed up to 109 protons cm−2 at 6.7 MeV. •We confirmed that it is radiation tolerant enough for space use. •We confirmed that a charge-injection technique reduces the CTI. •We confirmed that lowering the operating temperature also reduces the CTI

  2. CCD camera automatic calibration technology and ellipse recognition algorithm

    Institute of Scientific and Technical Information of China (English)

    Changku Sun; Xiaodong Zhang; Yunxia Qu

    2005-01-01

    A novel two-dimensional (2D) pattern used in camera calibration is presented. With one feature circle located at the center, an array of circles is photo-etched on this pattern. An ellipse recognition algorithm is proposed to implement the acquisition of interest calibration points without human intervention. According to the circle arrangement of the pattern, the relation between three-dimensional (3D) and 2D coordinates of these points can be established automatically and accurately. These calibration points are computed for intrinsic parameters calibration of charge-coupled device (CCD) camera with Tsai method. A series of experiments have shown that the algorithm is robust and reliable with the calibration error less than 0.4 pixel. This new calibration pattern and ellipse recognition algorithm can be widely used in computer vision.

  3. Research of fiber position measurement by multi CCD cameras

    Science.gov (United States)

    Zhou, Zengxiang; Hu, Hongzhuan; Wang, Jianping; Zhai, Chao; Chu, Jiaru; Liu, Zhigang

    2014-07-01

    Parallel controlled fiber positioner as an efficiency observation system, has been used in LAMOST for four years, and will be proposed in ngCFHT and rebuilt telescope Mayall. The fiber positioner research group in USTC have designed a new generation prototype by a close-packed module robotic positioner mechanisms. The prototype includes about 150 groups fiber positioning module plugged in 1 meter diameter honeycombed focal plane. Each module has 37 12mm diameter fiber positioners. Furthermore the new system promotes the accuracy from 40 um in LAMOST to 10um in MSDESI. That's a new challenge for measurement. Close-loop control system are to be used in new system. The CCD camera captures the photo of fiber tip position covered the focal plane, calculates the precise position information and feeds back to control system. After the positioner rotated several loops, the accuracy of all positioners will be confined to less than 10um. We report our component development and performance measurement program of new measuring system by using multi CCD cameras. With the stereo vision and image processing method, we precisely measure the 3-demension position of fiber tip carried by fiber positioner. Finally we present baseline parameters for the fiber positioner measurement as a reference of next generation survey telescope design.

  4. CCD Camera Lens Interface for Real-Time Theodolite Alignment

    Science.gov (United States)

    Wake, Shane; Scott, V. Stanley, III

    2012-01-01

    Theodolites are a common instrument in the testing, alignment, and building of various systems ranging from a single optical component to an entire instrument. They provide a precise way to measure horizontal and vertical angles. They can be used to align multiple objects in a desired way at specific angles. They can also be used to reference a specific location or orientation of an object that has moved. Some systems may require a small margin of error in position of components. A theodolite can assist with accurately measuring and/or minimizing that error. The technology is an adapter for a CCD camera with lens to attach to a Leica Wild T3000 Theodolite eyepiece that enables viewing on a connected monitor, and thus can be utilized with multiple theodolites simultaneously. This technology removes a substantial part of human error by relying on the CCD camera and monitors. It also allows image recording of the alignment, and therefore provides a quantitative means to measure such error.

  5. Perfecting the Photometric Calibration of the ACS CCD Cameras

    CERN Document Server

    Bohlin, Ralph C

    2016-01-01

    Newly acquired data and improved data reduction algorithms mandate a fresh look at the absolute flux calibration of the CCD cameras on the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS). The goals are to achieve a 1\\% accuracy and to make this calibration more accessible to the HST guest investigator. Absolute fluxes from the CALSPEC\\footnote{http://www.stsci.edu/hst/observatory/crds/calspec.html} database for three primary hot 30,000--60,000K WDs define the sensitivity calibrations for the WFC and HRC filters. The external uncertainty for the absolute flux is $\\sim$1\\%, while the internal consistency of the sensitivities in the broadband ACS filters is $\\sim$0.3\\% among the three primary WD flux standards. For stars as cool as K type, the agreement with the CALSPEC standards is within 1\\% at the WFC1-1K subarray position, which achieves the 1\\% precision goal for the first time. After making a small adjustment to the filter bandpass for F814W, the 1\\% precision goal is achieved over the full ...

  6. The in-flight spectroscopic performance of the Swift XRT CCD camera

    OpenAIRE

    Osborne, J. P.; Beardmore, A. P.; Godet, O.; Abbey, A. F.; Goad, M. R.; Page, K. L.; Wells, A. A.; Angelini, L; Burrows, D. N.; S. Campana; Chincarini, G.; Citterio, O.; Cusumano, G.; Giommi, P.; Hill, J.E.

    2005-01-01

    The Swift X-ray Telescope (XRT) focal plane camera is a front-illuminated MOS CCD, providing a spectral response kernel of 144 eV FWHM at 6.5 keV. We describe the CCD calibration program based on celestial and on-board calibration sources, relevant in-flight experiences, and developments in the CCD response model. We illustrate how the revised response model describes the calibration sources well. Loss of temperature control motivated a laboratory program to re-optimize the CCD substrate volt...

  7. A Low Noise, High QE, Large Format CCD Camera System for the NASA MIGHTI Instrument

    Science.gov (United States)

    Hancock, J. J.; Cardon, J.; Watson, M.; Cook, J.; Whiteley, M.; Beukers, J.; Englert, C. R.; Brown, C. M.; Harlander, J.

    2015-12-01

    The Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI) instrument is part of the NASA Ionspheric Connection Explorer (ICON) mission designed to uncover the mysteries of the extreme variability of the Earth's ionosphere. MIGHTI consists of two identical units positioned to observe the Earth's low latitude thermosphere from perpendicular viewing directions. The MIGHTI instrument is a spatial heterodyne spectrometer and requires a low noise, high QE, large format camera system to detect slight phase changes in the fringe patterns which reveal the neutral wind velocity. The MIGHTI camera system uses a single control electronics box to operate two identical CCD camera heads and communicate with the ICON payload electronics. The control electronics are carefully designed for a low noise implementation of CCD biases, clocking, and CCD output digitization. The camera heads consist of a 2k by 2K, back-illuminated, frame transfer CCD provided by e2v. The CCD's are both TEC cooled and have butcher-block filters mounted in close proximity of the active area. The CCDs are nominally operated in binned mode, the control electronics register settings provide flexibility for binning and gain control. An engineering model of the camera system has been assembled and tested. The EM camera system characterization meets all performance requirements. Performance highlights include a measured read noise of 5.7 electrons and dark current of 0.01 electronics/pixel/second. The camera system design and characterization results will be presented.

  8. Radiation damage of the PCO Pixelfly VGA CCD camera of the BES system on KSTAR tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Náfrádi, Gábor, E-mail: nafradi@reak.bme.hu [NTI, BME, EURATOM Association, H-1111 Budapest (Hungary); Kovácsik, Ákos, E-mail: kovacsik.akos@reak.bme.hu [NTI, BME, EURATOM Association, H-1111 Budapest (Hungary); Pór, Gábor, E-mail: por@reak.bme.hu [NTI, BME, EURATOM Association, H-1111 Budapest (Hungary); Lampert, Máté, E-mail: lampert.mate@wigner.mta.hu [Wigner RCP, RMI, EURATOM Association, POB 49, 1525 Budapest (Hungary); Un Nam, Yong, E-mail: yunam@nfri.re.kr [NFRI, 169-148 Gwahak-Ro, Yuseong-Gu, Daejeon 305-806 (Korea, Republic of); Zoletnik, Sándor, E-mail: zoletnik.sandor@wigner.mta.hu [Wigner RCP, RMI, EURATOM Association, POB 49, 1525 Budapest (Hungary)

    2015-01-11

    A PCO Pixelfly VGA CCD camera which is part a of the Beam Emission Spectroscopy (BES) diagnostic system of the Korea Superconducting Tokamak Advanced Research (KSTAR) used for spatial calibrations, suffered from serious radiation damage, white pixel defects have been generated in it. The main goal of this work was to identify the origin of the radiation damage and to give solutions to avoid it. Monte Carlo N-Particle eXtended (MCNPX) model was built using Monte Carlo Modeling Interface Program (MCAM) and calculations were carried out to predict the neutron and gamma-ray fields in the camera position. Besides the MCNPX calculations pure gamma-ray irradiations of the CCD camera were carried out in the Training Reactor of BME. Before, during and after the irradiations numerous frames were taken with the camera with 5 s long exposure times. The evaluation of these frames showed that with the applied high gamma-ray dose (1.7 Gy) and dose rate levels (up to 2 Gy/h) the number of the white pixels did not increase. We have found that the origin of the white pixel generation was the neutron-induced thermal hopping of the electrons which means that in the future only neutron shielding is necessary around the CCD camera. Another solution could be to replace the CCD camera with a more radiation tolerant one for example with a suitable CMOS camera or apply both solutions simultaneously.

  9. High-speed optical shutter coupled to fast-readout CCD camera

    Science.gov (United States)

    Yates, George J.; Pena, Claudine R.; McDonald, Thomas E., Jr.; Gallegos, Robert A.; Numkena, Dustin M.; Turko, Bojan T.; Ziska, George; Millaud, Jacques E.; Diaz, Rick; Buckley, John; Anthony, Glen; Araki, Takae; Larson, Eric D.

    1999-04-01

    A high frame rate optically shuttered CCD camera for radiometric imaging of transient optical phenomena has been designed and several prototypes fabricated, which are now in evaluation phase. the camera design incorporates stripline geometry image intensifiers for ultra fast image shutters capable of 200ps exposures. The intensifiers are fiber optically coupled to a multiport CCD capable of 75 MHz pixel clocking to achieve 4KHz frame rate for 512 X 512 pixels from simultaneous readout of 16 individual segments of the CCD array. The intensifier, Philips XX1412MH/E03 is generically a Generation II proximity-focused micro channel plate intensifier (MCPII) redesigned for high speed gating by Los Alamos National Laboratory and manufactured by Philips Components. The CCD is a Reticon HSO512 split storage with bi-direcitonal vertical readout architecture. The camera main frame is designed utilizing a multilayer motherboard for transporting CCD video signals and clocks via imbedded stripline buses designed for 100MHz operation. The MCPII gate duration and gain variables are controlled and measured in real time and up-dated for data logging each frame, with 10-bit resolution, selectable either locally or by computer. The camera provides both analog and 10-bit digital video. The camera's architecture, salient design characteristics, and current test data depicting resolution, dynamic range, shutter sequences, and image reconstruction will be presented and discussed.

  10. Measurement of soft x-ray image by using CCD camera for long pulse discharge

    International Nuclear Information System (INIS)

    A soft x-ray imaging was made a CCD camera installed to a tangential port in LHD. The large number of pixels (1024x512) of with CCD gives a good spatial resolution of 1.8 mm. The tangential soft x-ray image is obtained during long pulse discharge on LHD with a time resolution of 0.5 s. The shift of x-ray emission profile is found for plasmas with different magnetic axes. (J.P.N.)

  11. High performance CCD camera system for digitalisation of 2D DIGE gels.

    Science.gov (United States)

    Strijkstra, Annemieke; Trautwein, Kathleen; Roesler, Stefan; Feenders, Christoph; Danzer, Daniel; Riemenschneider, Udo; Blasius, Bernd; Rabus, Ralf

    2016-07-01

    An essential step in 2D DIGE-based analysis of differential proteome profiles is the accurate and sensitive digitalisation of 2D DIGE gels. The performance progress of commercially available charge-coupled device (CCD) camera-based systems combined with light emitting diodes (LED) opens up a new possibility for this type of digitalisation. Here, we assessed the performance of a CCD camera system (Intas Advanced 2D Imager) as alternative to a traditionally employed, high-end laser scanner system (Typhoon 9400) for digitalisation of differential protein profiles from three different environmental bacteria. Overall, the performance of the CCD camera system was comparable to the laser scanner, as evident from very similar protein abundance changes (irrespective of spot position and volume), as well as from linear range and limit of detection. PMID:27252121

  12. High performance CCD camera system for digitalisation of 2D DIGE gels.

    Science.gov (United States)

    Strijkstra, Annemieke; Trautwein, Kathleen; Roesler, Stefan; Feenders, Christoph; Danzer, Daniel; Riemenschneider, Udo; Blasius, Bernd; Rabus, Ralf

    2016-07-01

    An essential step in 2D DIGE-based analysis of differential proteome profiles is the accurate and sensitive digitalisation of 2D DIGE gels. The performance progress of commercially available charge-coupled device (CCD) camera-based systems combined with light emitting diodes (LED) opens up a new possibility for this type of digitalisation. Here, we assessed the performance of a CCD camera system (Intas Advanced 2D Imager) as alternative to a traditionally employed, high-end laser scanner system (Typhoon 9400) for digitalisation of differential protein profiles from three different environmental bacteria. Overall, the performance of the CCD camera system was comparable to the laser scanner, as evident from very similar protein abundance changes (irrespective of spot position and volume), as well as from linear range and limit of detection.

  13. Theodolite with CCD Camera for Safe Measurement of Laser-Beam Pointing

    Science.gov (United States)

    Crooke, Julie A.

    2003-01-01

    The simple addition of a charge-coupled-device (CCD) camera to a theodolite makes it safe to measure the pointing direction of a laser beam. The present state of the art requires this to be a custom addition because theodolites are manufactured without CCD cameras as standard or even optional equipment. A theodolite is an alignment telescope equipped with mechanisms to measure the azimuth and elevation angles to the sub-arcsecond level. When measuring the angular pointing direction of a Class ll laser with a theodolite, one could place a calculated amount of neutral density (ND) filters in front of the theodolite s telescope. One could then safely view and measure the laser s boresight looking through the theodolite s telescope without great risk to one s eyes. This method for a Class ll visible wavelength laser is not acceptable to even consider tempting for a Class IV laser and not applicable for an infrared (IR) laser. If one chooses insufficient attenuation or forgets to use the filters, then looking at the laser beam through the theodolite could cause instant blindness. The CCD camera is already commercially available. It is a small, inexpensive, blackand- white CCD circuit-board-level camera. An interface adaptor was designed and fabricated to mount the camera onto the eyepiece of the specific theodolite s viewing telescope. Other equipment needed for operation of the camera are power supplies, cables, and a black-and-white television monitor. The picture displayed on the monitor is equivalent to what one would see when looking directly through the theodolite. Again, the additional advantage afforded by a cheap black-and-white CCD camera is that it is sensitive to infrared as well as to visible light. Hence, one can use the camera coupled to a theodolite to measure the pointing of an infrared as well as a visible laser.

  14. The in-flight spectroscopic performance of the Swift XRT CCD camera during 2006-2007

    OpenAIRE

    Godet, O.; Beardmore, A. P.; Abbey, A. F.; Osborne, J. P.; Page, K. L.; Tyler, L.; Burrows, D. N.; Evans, P.; Starling, R.; Wells, A. A.; Angelini, L; S. Campana; Chincarini, G.; Citterio, O.; Cusumano, G.

    2007-01-01

    The Swift X-ray Telescope focal plane camera is a front-illuminated MOS CCD, providing a spectral response kernel of 135 eV FWHM at 5.9 keV as measured before launch. We describe the CCD calibration program based on celestial and on-board calibration sources, relevant in-flight experiences, and developments in the CCD response model. We illustrate how the revised response model describes the calibration sources well. Comparison of observed spectra with models folded through the instrument res...

  15. Volumetric Diffuse Optical Tomography for Small Animals Using a CCD-Camera-Based Imaging System

    Directory of Open Access Journals (Sweden)

    Zi-Jing Lin

    2012-01-01

    Full Text Available We report the feasibility of three-dimensional (3D volumetric diffuse optical tomography for small animal imaging by using a CCD-camera-based imaging system with a newly developed depth compensation algorithm (DCA. Our computer simulations and laboratory phantom studies have demonstrated that the combination of a CCD camera and DCA can significantly improve the accuracy in depth localization and lead to reconstruction of 3D volumetric images. This approach may present great interests for noninvasive 3D localization of an anomaly hidden in tissue, such as a tumor or a stroke lesion, for preclinical small animal models.

  16. Auto-measurement system of aerial camera lens' resolution based on orthogonal linear CCD

    Science.gov (United States)

    Zhao, Yu-liang; Zhang, Yu-ye; Ding, Hong-yi

    2010-10-01

    The resolution of aerial camera lens is one of the most important camera's performance indexes. The measurement and calibration of resolution are important test items in in maintenance of camera. The traditional method that is observing resolution panel of collimator rely on human's eyes using microscope and doing some computing. The method is of low efficiency and susceptible to artificial factors. The measurement results are unstable, too. An auto-measurement system of aerial camera lens' resolution, which uses orthogonal linear CCD sensor as the detector to replace reading microscope, is introduced. The system can measure automatically and show result real-timely. In order to measure the smallest diameter of resolution panel which could be identified, two orthogonal linear CCD is laid on the imaging plane of measured lens and four intersection points are formed on the orthogonal linear CCD. A coordinate system is determined by origin point of the linear CCD. And a circle is determined by four intersection points. In order to obtain the circle's radius, firstly, the image of resolution panel is transformed to pulse width of electric signal which is send to computer through amplifying circuit and threshold comparator and counter. Secondly, the smallest circle would be extracted to do measurement. The circle extraction made using of wavelet transform which has character of localization in the domain of time and frequency and has capability of multi-scale analysis. Lastly, according to the solution formula of lens' resolution, we could obtain the resolution of measured lens. The measuring precision on practical measurement is analyzed, and the result indicated that the precision will be improved when using linear CCD instead of reading microscope. Moreover, the improvement of system error is determined by the pixel's size of CCD. With the technique of CCD developed, the pixel's size will smaller, the system error will be reduced greatly too. So the auto

  17. Images processing in hostile nuclear environments. Experimental CCD cameras tests results for robotic operations

    International Nuclear Information System (INIS)

    This paper describes succinctly the hostile aspect of nuclear environment for visual sensors and transmissions. It approaches the new field of nuclear Robotic and its constraints about vision process. Tolerance tests of CCD cameras in gamma radiations environment are displayed: - gamma dosimetry measures, - electrical measurement process, - views during testing, - degradations and better tolerance hypothesis

  18. Applications in radiation therapy of a scintillating screen viewed by a CCD camera

    NARCIS (Netherlands)

    Schippers, J.M.; Boon, S.N.; van Luijk, P.

    2002-01-01

    A two-dimensional (2D) dosimetry system has been designed for position-sensitive dose-measurement applications in modem radiation therapy. The system consists of a scintillating screen (Gd2O2S:Tb), observed by a low-noise CCD camera with a long integration time. The system allows reliable and accura

  19. Perfecting the Photometric Calibration of the ACS CCD Cameras

    Science.gov (United States)

    Bohlin, Ralph C.

    2016-09-01

    Newly acquired data and improved data reduction algorithms mandate a fresh look at the absolute flux calibration of the charge-coupled device cameras on the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS). The goals are to achieve a 1% accuracy and to make this calibration more accessible to the HST guest investigator. Absolute fluxes from the CALSPEC1 database for three primary hot 30,000–60,000K WDs define the sensitivity calibrations for the Wide Field Channel (WFC) and High Resolution Channel (HRC) filters. The external uncertainty for the absolute flux is ˜1%, while the internal consistency of the sensitivities in the broadband ACS filters is ˜0.3% among the three primary WD flux standards. For stars as cool as K type, the agreement with the CALSPEC standards is within 1% at the WFC1-1K subarray position, which achieves the 1% precision goal for the first time. After making a small adjustment to the filter bandpass for F814W, the 1% precision goal is achieved over the full F814W WFC field of view for stars of K type and hotter. New encircled energies and absolute sensitivities replace the seminal results of Sirianni et al. that were published in 2005. After implementing the throughput updates, synthetic predictions of the WFC and HRC count rates for the average of the three primary WD standard stars agree with the observations to 0.1%.

  20. Perfecting the Photometric Calibration of the ACS CCD Cameras

    Science.gov (United States)

    Bohlin, Ralph C.

    2016-09-01

    Newly acquired data and improved data reduction algorithms mandate a fresh look at the absolute flux calibration of the charge-coupled device cameras on the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS). The goals are to achieve a 1% accuracy and to make this calibration more accessible to the HST guest investigator. Absolute fluxes from the CALSPEC1 database for three primary hot 30,000-60,000K WDs define the sensitivity calibrations for the Wide Field Channel (WFC) and High Resolution Channel (HRC) filters. The external uncertainty for the absolute flux is ˜1%, while the internal consistency of the sensitivities in the broadband ACS filters is ˜0.3% among the three primary WD flux standards. For stars as cool as K type, the agreement with the CALSPEC standards is within 1% at the WFC1-1K subarray position, which achieves the 1% precision goal for the first time. After making a small adjustment to the filter bandpass for F814W, the 1% precision goal is achieved over the full F814W WFC field of view for stars of K type and hotter. New encircled energies and absolute sensitivities replace the seminal results of Sirianni et al. that were published in 2005. After implementing the throughput updates, synthetic predictions of the WFC and HRC count rates for the average of the three primary WD standard stars agree with the observations to 0.1%.

  1. Time-resolved spectra of dense plasma focus using spectrometer, streak camera, and CCD combination

    Energy Technology Data Exchange (ETDEWEB)

    Goldin, F. J. [Livermore Operations, National Security Technologies, LLC, Livermore, California 94550 (United States); Meehan, B. T.; Hagen, E. C. [North Las Vegas Facility, National Security Technologies, LLC, North Las Vegas, Nevada 89030 (United States); Wilkins, P. R. [Lawrence Livermore National Laboratories, Livermore, California 94550 (United States)

    2010-10-15

    A time-resolving spectrographic instrument has been assembled with the primary components of a spectrometer, image-converting streak camera, and CCD recording camera, for the primary purpose of diagnosing highly dynamic plasmas. A collection lens defines the sampled region and couples light from the plasma into a step index, multimode fiber which leads to the spectrometer. The output spectrum is focused onto the photocathode of the streak camera, the output of which is proximity-coupled to the CCD. The spectrometer configuration is essentially Czerny-Turner, but off-the-shelf Nikon refraction lenses, rather than mirrors, are used for practicality and flexibility. Only recently assembled, the instrument requires significant refinement, but has now taken data on both bridge wire and dense plasma focus experiments.

  2. Time-Resolved Spectra of Dense Plasma Focus Using Spectrometer, Streak Camera, CCD Combination

    Energy Technology Data Exchange (ETDEWEB)

    F. J. Goldin, B. T. Meehan, E. C. Hagen, P. R. Wilkins

    2010-10-01

    A time-resolving spectrographic instrument has been assembled with the primary components of a spectrometer, image-converting streak camera, and CCD recording camera, for the primary purpose of diagnosing highly dynamic plasmas. A collection lens defines the sampled region and couples light from the plasma into a step index, multimode fiber which leads to the spectrometer. The output spectrum is focused onto the photocathode of the streak camera, the output of which is proximity-coupled to the CCD. The spectrometer configuration is essentially Czerny–Turner, but off-the-shelf Nikon refraction lenses, rather than mirrors, are used for practicality and flexibility. Only recently assembled, the instrument requires significant refinement, but has now taken data on both bridge wire and dense plasma focus experiments.

  3. Use of a C.C.D. array in an X-ray pinhole camera

    International Nuclear Information System (INIS)

    X-ray imaging adapted to the laser-matter interaction experiments consits in recording plasma images from its X-ray emission; those phenomena have between 100 ps and some nanoseconds duration. When we only need spatial information on 1-10 keV X-ray emission, the most simple imaging device is the pinhole camera; the two dimension image of the plasma is temporally integrated by an X-ray sensitive detector. Until now, X-ray film was used. Its operation and processing were long and tedious, so we replaced it by a television camera built around a Charge Coupled device (C.C.D.). This camera is directly integrated in the pinhole camera. The X-ray detection is made by the silicon substrat of a C.C.D. without input window working in the vacuum of the experiment chamber; a compact camera head (40 mm diameter, 120 mm length) located near the C.C.D. (1 to 2 cm) makes the charge voltage conversion and the signal amplification. The immediate operation of images is done by an image acquisition and processing unit after digitizing the video signal on 8 bits. From measurements made on a continuous X-ray source (5,4 keV) we could point out the fact that a THOMSON-CSF THX 31135 CCD is 10 times more sensitive than the X-ray SB2 KODAK film that we use in pinhole cameras. The dynamic range measured in these conditions was about 300. The first experimental results obtained on a pulsed X-ray source are presented

  4. Multi-spectral CCD camera system for ocean water color and seacoast observation

    Science.gov (United States)

    Zhu, Min; Chen, Shiping; Wu, Yanlin; Huang, Qiaolin; Jin, Weiqi

    2001-10-01

    One of the earth observing instruments on HY-1 Satellite which will be launched in 2001, the multi-spectral CCD camera system, is developed by Beijing Institute of Space Mechanics & Electricity (BISME), Chinese Academy of Space Technology (CAST). In 798 km orbit, the system can provide images with 250 m ground resolution and a swath of 500 km. It is mainly used for coast zone dynamic mapping and oceanic watercolor monitoring, which include the pollution of offshore and coast zone, plant cover, watercolor, ice, terrain underwater, suspended sediment, mudflat, soil and vapor gross. The multi- spectral camera system is composed of four monocolor CCD cameras, which are line array-based, 'push-broom' scanning cameras, and responding for four spectral bands. The camera system adapts view field registration; that is, each camera scans the same region at the same moment. Each of them contains optics, focal plane assembly, electrical circuit, installation structure, calibration system, thermal control and so on. The primary features on the camera system are: (1) Offset of the central wavelength is better than 5 nm; (2) Degree of polarization is less than 0.5%; (3) Signal-to-noise ratio is about 1000; (4) Dynamic range is better than 2000:1; (5) Registration precision is better than 0.3 pixel; (6) Quantization value is 12 bit.

  5. White light single-shot interferometry with colour CCD camera for optical inspection of microsystems

    Science.gov (United States)

    Upputuri, Paul Kumar; Pramanik, Manojit; Nandigana, Krishna Mohan; Kothiyal, Mahendra Prasad

    2015-07-01

    White light interferometry is a well-established optical tool for surface metrology of reflective samples. In this work, we discuss a single-shot white light interferometer based on single-chip color CCD camera and Hilbert transformation. The approach makes the measurement dynamic, faster, easier and cost-effective for industrial applications. Here we acquire only one white light interferogram using colour CCD camera and then decompose into its individual components using software. We present a simple Hilbert transformation approach to remove the non-uniform bias associated with the interference signal. The phases at individual wavelengths are calculated using Hilbert transformation. The use of Hilbert transformation introduces phase error which depends on number of fringe cycles. We discuss these errors. Experimental results on reflective micro-scale-samples for surface profiling are presented.

  6. Application of CCD-camera for size measuring of electron ring by means of synchrotron radiation

    International Nuclear Information System (INIS)

    The method is described and the results of measuring of electron ring density distribution are presented. A TV-camera on the basis of a CCD matrix is used as a sensing element. The camera is connected through the interface unit in CAMAC standard with the SM-4 computer. The time exposition of radiaiton is realized by using an electro-optic sutter in the time interval from 0.01 to 1 ms at an operation voltage of 1 kV. 5 refs

  7. On-Line High Dose-Rate Gamma Ray Irradiation Test of the CCD/CMOS Cameras

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jai Wan; Jeong, Kyung Min [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    In this paper, test results of gamma ray irradiation to CCD/CMOS cameras are described. From the CAMS (containment atmospheric monitoring system) data of Fukushima Dai-ichi nuclear power plant station, we found out that the gamma ray dose-rate when the hydrogen explosion occurred in nuclear reactors 1{approx}3 is about 160 Gy/h. If assumed that the emergency response robot for the management of severe accident of the nuclear power plant has been sent into the reactor area to grasp the inside situation of reactor building and to take precautionary measures against releasing radioactive materials, the CCD/CMOS cameras, which are loaded with the robot, serve as eye of the emergency response robot. In the case of the Japanese Quince robot system, which was sent to carry out investigating the unit 2 reactor building refueling floor situation, 7 CCD/CMOS cameras are used. 2 CCD cameras of Quince robot are used for the forward and backward monitoring of the surroundings during navigation. And 2 CCD (or CMOS) cameras are used for monitoring the status of front-end and back-end motion mechanics such as flippers and crawlers. A CCD camera with wide field of view optics is used for monitoring the status of the communication (VDSL) cable reel. And another 2 CCD cameras are assigned for reading the indication value of the radiation dosimeter and the instrument. In the preceding assumptions, a major problem which arises when dealing with CCD/CMOS cameras in the severe accident situations of the nuclear power plant is the presence of high dose-rate gamma irradiation fields. In the case of the DBA (design basis accident) situations of the nuclear power plant, in order to use a CCD/CMOS camera as an ad-hoc monitoring unit in the vicinity of high radioactivity structures and components of the nuclear reactor area, a robust survivability of this camera in such intense gamma-radiation fields therefore should be verified. The CCD/CMOS cameras of various types were gamma irradiated at a

  8. OmegaCAM: the 16k×16k CCD camera for the VLT survey telescope

    NARCIS (Netherlands)

    Kuijken, K.; Bender, R.; Cappellaro, E.; Muschielok, B.; Baruffolo, A.; Cascone, E.; Iwert, O.; Mitsch, W.; Nicklas, H.; Valentijn, E. A.; Baade, D.; Begeman, K. G.; Bortolussi, A.; Boxhoorn, D.; Christen, F.; Deul, E. R.; Geimer, C.; Greggio, L.; Harke, R.; Häfner, R.; Hess, G.; Hess, H.-J.; Hopp, U.; Ilijevski, I.; Klink, G.; Kravcar, H.; Lizon, J. L.; Magagna, C. E.; Müller, Ph.; Niemeczek, R.; de Pizzol, L.; Poschmann, H.; Reif, K.; Rengelink, R.; Reyes, J.; Silber, A.; Wellem, W.

    2002-01-01

    In 2004, OmegaCAM will start operations on Paranal as the sole instrument on the 2.6-m VLT Survey Telescope. OmegaCAM is a huge optical CCD imaging camera: its 16k × 16k CCD pixels cover the square degree field of view of the VST almost entirely. The primary function of the VST and its instrument is

  9. A directional fast neutron detector using scintillating fibers and an intensified CCD camera system

    International Nuclear Information System (INIS)

    We have been developing and testing a scintillating fiber detector (SFD) for use as a fast neutron sensor which can discriminate against neutrons entering at angles non-parallel to the fiber axis (''directionality''). The detector/convertor component is a fiber bundle constructed of plastic scintillating fibers each measuring 10 cm long and either 0.3 mm or 0.5 mm in diameter. Extensive Monte Carlo simulations were made to optimize the bundle response to a range of fast neutron energies and to intense fluxes of high energy gamma-rays. The bundle is coupled to a set of gamma-ray insenitive electro-optic intensifiers whose output is viewed by a CCD camera directly coupled to the intensifiers. Two types of CCD cameras were utilized: 1) a standard, interline RS-170 camera with electronic shuttering and 2) a high-speed (up to 850 frame/s) field-transfer camera. Measurements of the neutron detection efficiency and directionality were made using 14 MeV neutrons, and the response to gamma-rays was performed using intense fluxes from radioisotopic sources (up to 20 R/h). Recently, the detector was constructed and tested using a large 10 cm by 10 cm square fiber bundle coupled to a 10 cm diameter GEN I intensifier tube. We present a description of the various detector systems and report the results of experimental tests. ((orig.))

  10. Numerical simulations and analyses of temperature control loop heat pipe for space CCD camera

    Science.gov (United States)

    Meng, Qingliang; Yang, Tao; Li, Chunlin

    2016-10-01

    As one of the key units of space CCD camera, the temperature range and stability of CCD components affect the image's indexes. Reasonable thermal design and robust thermal control devices are needed. One kind of temperature control loop heat pipe (TCLHP) is designed, which highly meets the thermal control requirements of CCD components. In order to study the dynamic behaviors of heat and mass transfer of TCLHP, particularly in the orbital flight case, a transient numerical model is developed by using the well-established empirical correlations for flow models within three dimensional thermal modeling. The temperature control principle and details of mathematical model are presented. The model is used to study operating state, flow and heat characteristics based upon the analyses of variations of temperature, pressure and quality under different operating modes and external heat flux variations. The results indicate that TCLHP can satisfy the thermal control requirements of CCD components well, and always ensure good temperature stability and uniformity. By comparison between flight data and simulated results, it is found that the model is to be accurate to within 1°C. The model can be better used for predicting and understanding the transient performance of TCLHP.

  11. Non-Metric CCD Camera Calibration Algorithm in a Digital Photogrammetry System

    Institute of Scientific and Technical Information of China (English)

    YANG Hua-chao; DENG Ka-zhong; ZHANG Shu-bi; GUO Guang-li; ZHOU Ming

    2006-01-01

    Camera calibration is a critical process in photogrammetry and a necessary step to acquire 3D information from a 2D image. In this paper, a flexible approach for CCD camera calibration using 2D direct linear transformation (DLT) and bundle adjustment is proposed. The proposed approach assumes that the camera interior orientation elements are known, and addresses a new closed form solution in planar object space based on homogenous coordinate representation and matrix factorization. Homogeneous coordinate representation offers a direct matrix correspondence between the parameters of the 2D DLT and the collinearity equation. The matrix factorization starts by recovering the elements of the rotation matrix and then solving for the camera position with the collinearity equation. Camera calibration with high precision is addressed by bundle adjustment using the initial values of the camera orientation elements. The results show that the calibration precision of principal point and focal length is about 0.2 and 0.3 pixels respectively, which can meet the requirements of close-range photogrammetry with high accuracy.

  12. A pnCCD-based, fast direct single electron imaging camera for TEM and STEM

    Science.gov (United States)

    Ryll, H.; Simson, M.; Hartmann, R.; Holl, P.; Huth, M.; Ihle, S.; Kondo, Y.; Kotula, P.; Liebel, A.; Müller-Caspary, K.; Rosenauer, A.; Sagawa, R.; Schmidt, J.; Soltau, H.; Strüder, L.

    2016-04-01

    We report on a new camera that is based on a pnCCD sensor for applications in scanning transmission electron microscopy. Emerging new microscopy techniques demand improved detectors with regards to readout rate, sensitivity and radiation hardness, especially in scanning mode. The pnCCD is a 2D imaging sensor that meets these requirements. Its intrinsic radiation hardness permits direct detection of electrons. The pnCCD is read out at a rate of 1,150 frames per second with an image area of 264 x 264 pixel. In binning or windowing modes, the readout rate is increased almost linearly, for example to 4000 frames per second at 4× binning (264 x 66 pixel). Single electrons with energies from 300 keV down to 5 keV can be distinguished due to the high sensitivity of the detector. Three applications in scanning transmission electron microscopy are highlighted to demonstrate that the pnCCD satisfies experimental requirements, especially fast recording of 2D images. In the first application, 65536 2D diffraction patterns were recorded in 70 s. STEM images corresponding to intensities of various diffraction peaks were reconstructed. For the second application, the microscope was operated in a Lorentz-like mode. Magnetic domains were imaged in an area of 256 x 256 sample points in less than 37 seconds for a total of 65536 images each with 264 x 132 pixels. Due to information provided by the two-dimensional images, not only the amplitude but also the direction of the magnetic field could be determined. In the third application, millisecond images of a semiconductor nanostructure were recorded to determine the lattice strain in the sample. A speed-up in measurement time by a factor of 200 could be achieved compared to a previously used camera system.

  13. Calibration of the photometric method of heavy ion charge measurements in emulsion using a CCD camera

    CERN Document Server

    Kudzia, D; Wilczynski, H

    2002-01-01

    A previously developed method of heavy ion charge measurements in emulsion has been significantly improved. The charge measurements are based on analysis of photometric profiles of the particle tracks in emulsion. These profiles are obtained using a CCD camera mounted on an optical microscope. So far, the manual charge determination by delta ray counting had to be used for calibration of the photometric method. In this paper a complete procedure for calibration of the photometric method is shown, without resorting to the manual method.

  14. Measurement of charge of heavy ions in emulsion using a CCD camera

    CERN Document Server

    Kudzia, D; Dabrowska, A; Deines-Jones, P; Holynski, R; Olszewski, A; Nilsen, B S; Sen-Gupta, K; Szarska, M; Trzupek, A; Waddington, C J; Wefel, J P; Wilczynska, B; Wilczynski, H; Wolter, W; Wosiek, B; Wozniak, K

    1999-01-01

    A system has been developed for semi-automated determination of the charges of heavy ions recorded in nuclear emulsions. The profiles of various heavy ion tracks in emulsion, both accelerator beam ions and fragments of heavy projectiles, were obtained with a CCD camera mounted on a microscope. The dependence of track profiles on illumination, emulsion grain size and density, background in emulsion, and track geometry was analyzed. Charges of the fragments of heavy projectiles were estimated independently by the delta ray counting method. A calibration of both width and height of track profiles against ion charges was made with ions of known charges ranging from helium to gold nuclei. (author)

  15. Upwelling radiance at 976 nm measured from space using the OPALS CCD camera on the ISS

    Science.gov (United States)

    Biswas, Abhijit; Kovalik, Joseph M.; Oaida, Bogdan V.; Abrahamson, Matthew; Wright, Malcolm W.

    2015-03-01

    The Optical Payload for Lasercomm Science (OPALS) Flight System on-board the International Space Station uses a charge coupled device (CCD) camera to detect a beacon laser from Earth. Relative measurements of the background contributed by upwelling radiance under diverse illumination conditions and varying surface terrain is presented. In some cases clouds in the field-of-view allowed a comparison of terrestrial and cloud-top upwelling radiance. In this paper we will report these measurements and examine the extent of agreement with atmospheric model predictions.

  16. Optical characterization of the SOFIA telescope using fast EM-CCD cameras

    Science.gov (United States)

    Pfüller, Enrico; Wolf, Jürgen; Hall, Helen; Röser, Hans-Peter

    2012-09-01

    The Stratospheric Observatory for Infrared Astronomy (SOFIA) has recently demonstrated its scientific capabilities in a first series of astronomical observing flights. In parallel, special measurements and engineering flights were conducted aiming at the characterization and the commissioning of the telescope and the complete airborne observatory. To support the characterization measurements, two commercial Andor iXon EM-CCD cameras have been used, a DU-888 dubbed Fast Diagnostic Camera (FDC) running at frame rates up to about 400 fps, and a DU-860 as a Super Fast Diagnostic Camera (SFDC) providing 2000 fps. Both cameras have been mounted to the telescope’s Focal Plane Imager (FPI) flange in lieu of the standard FPI tracking camera. Their fast image sequences have been used to analyze and to improve the telescope’s pointing stability, especially to help tuning active mass dampers that suppress eigenfrequencies in the telescope system, to characterize and to optimize the chopping secondary mirror and to investigate the structure and behavior of the shear layer that forms over the open telescope cavity in flight. In June 2011, a collaboration between the HIPO science instrument team, the MIT’s stellar occultation group and the FDC team, led to the first SOFIA observation of a stellar occultation by the dwarf planet Pluto over the Pacific.

  17. Development of the analog ASIC for multi-channel readout X-ray CCD camera

    CERN Document Server

    Nakajima, Hiroshi; Idehara, Toshihiro; Anabuki, Naohisa; Tsunemi, Hiroshi; Doty, John P; Ikeda, Hirokazu; Katayama, Haruyoshi; Kitamura, Hisashi; Uchihori, Yukio; 10.1016/j.nima.2010.12.174

    2011-01-01

    We report on the performance of an analog application-specific integrated circuit (ASIC) developed aiming for the front-end electronics of the X-ray CCDcamera system onboard the next X-ray astronomical satellite, ASTRO-H. It has four identical channels that simultaneously process the CCD signals. Distinctive capability of analog-to-digital conversion enables us to construct a CCD camera body that outputs only digital signals. As the result of the front-end electronics test, it works properly with low input noise of =<30 uV at the pixel rate below 100 kHz. The power consumption is sufficiently low of about 150 mW/chip. The input signal range of 720 mV covers the effective energy range of the typical X-ray photon counting CCD (up to 20 keV). The integrated non-linearity is 0.2% that is similar as those of the conventional CCDs in orbit. We also performed a radiation tolerance test against the total ionizing dose (TID) effect and the single event effect. The irradiation test using 60Co and proton beam showed ...

  18. Front- vs. back-illuminated CCD cameras for photometric surveys: a noise budget analysis

    CERN Document Server

    Crouzet, Nicolas; Fressin, Francois; Blazit, Alain

    2008-01-01

    Exoplanetary transit and stellar oscillation surveys require a very high precision photometry. The instrumental noise has therefore to be minimized. First, we perform a semi-analytical model of different noise sources. We show that the noise due the CCD electrodes can be overcome using a Gaussian PSF (Point Spread Function) of full width half maximum larger than 1.6 pixels. We also find that for a PSF size of a few pixels, the photometric aperture has to be at least 2.5 times larger than the PSF full width half maximum. Then, we compare a front- with a back-illuminated CCD through a Monte-Carlo simulation. Both cameras give the same results for a PSF full width half maximum larger than 1.5 pixels. All these simulations are applied to the A STEP (Antarctica Search for Transiting Extrasolar Planets) project. As a result, we choose a front-illuminated camera for A STEP because of its better resolution and lower price, and we will use a PSF larger than 1.6 pixels.

  19. A novel approach to accurate portal dosimetry using CCD-camera based EPIDs

    International Nuclear Information System (INIS)

    A new method for portal dosimetry using CCD camera-based electronic portal imaging devices (CEPIDs) is demonstrated. Unlike previous approaches, it is not based on a priori assumptions concerning CEPID cross-talk characteristics. In this method, the nonsymmetrical and position-dependent cross-talk is determined by directly imaging a set of cross-talk kernels generated by small fields ('pencil beams') exploiting the high signal-to-noise ratio of a cooled CCD camera. Signal calibration is achieved by imaging two reference fields. Next, portal dose images (PDIs) can be derived from electronic portal dose images (EPIs), in a fast forward-calculating iterative deconvolution. To test the accuracy of these EPI-based PDIs, a comparison is made to PDIs obtained by scanning diode measurements. The method proved accurate to within 0.2±0.7% (1 SD), for on-axis symmetrical and asymmetrical fields with different field widths and homogeneous phantom thicknesses, off-axis Alderson thorax fields and a strongly modulated IMRT field. Hence, the proposed method allows for fast, accurate portal dosimetry. In addition, it is demonstrated that the CEPID cross-talk signal is not only induced by optical photon reflection and scatter within the CEPID structure, but also by high-energy back-scattered radiation from CEPID elements (mirror and housing) towards the fluorescent screen

  20. Technical aspects and preliminary results of the CCD camera diagnostics on Extrap T2

    Energy Technology Data Exchange (ETDEWEB)

    Cecconello, M.; Brzozowski, J. [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Fusion Plasma Physics; Pugno, R. [Consorzio RFX, Padova (Italy)

    1999-05-01

    During the last months of Extrap T2 operations an imaging acquisition system, based on charge-coupled devices (CCD) cameras, has been operated. CCD cameras are a standard diagnostic used in many fusion experiments: i) to obtain a direct insight of the plasma behaviour during the pulse, of the evolution of plasma-wall interactions and, eventually, of locked modes, ii) to measure local quantities such as the wall temperature and the impurity influxes, iii) to study the hydrogen recycling behaviour and iv) to estimate the poloidal and toroidal mode numbers. One of the aims of our imaging campaign was to check the utility of such diagnostic for T2. The purpose of this report is to describe the technical aspects involved in the use of such diagnostic and to briefly describe the results obtained. In this view, this report aims to be a guide to the development of a dedicated image acquisition system for Extrap T2, after the planned rebuild, by stressing the problems and limitations encountered during this campaign 6 refs, 19 figs

  1. Performance of a slow-scan CCD camera for macromolecular imaging in a 400 kV electron cryomicroscope.

    Science.gov (United States)

    Sherman, M B; Brink, J; Chiu, W

    1996-04-01

    The feasibility and limitations of a 1024 x 1024 slow-scan charge-coupled device (CCD) camera were evaluated for imaging in a 400kV electron cryomicroscope. Catalase crystals and amorphous carbon film were used as test specimens. Using catalase crystals, it was found that the finite (24 microns) pixel size of the slow-scan CCD camera governs the ultimate resolution in the acquired images. For instance, spot-scan images of ice-embedded catalase crystals showed resolutions of 8 A and 4 A at effective magnifications of 67,000 x and 132,000 x, respectively. Using an amorphous carbon film, the damping effect of the modulation transfer function (MTF) of the slow-scan CCD camera on the specimen's Fourier spectrum relative to that of the photographic film was evaluated. The MTF of the slow-scan CCD camera fell off more rapidly compared to that of the photographic film and reached the value of 0.2 at the Nyquist frequency. Despite this attenuation, the signal-to-noise ratio of the CCD data, as determined from reflections of negatively-stained catalase crystals, was found to decrease to approximately 50% of that of photographic film data. The phases computed from images of the same negatively-stained catalase crystals recorded consecutively on both the slow-scan CCD camera and photographic film were found to be comparable to each other within 12 degrees. Ways of minimizing the effect of the MTF of the slow-scan CCD camera on the acquired images are also presented. PMID:8858867

  2. Performance of the low light level CCD camera for speckle imaging

    CERN Document Server

    Saha, S K

    2002-01-01

    A new generation CCD detector called low light level CCD (L3CCD) that performs like an intensified CCD without incorporating a micro channel plate (MCP) for light amplification was procured and tested. A series of short exposure images with millisecond integration time has been obtained. The L3CCD is cooled to about $-80^\\circ$ C by Peltier cooling.

  3. CTK-II & RTK: The CCD-cameras operated at the auxiliary telescopes of the University Observatory Jena

    Science.gov (United States)

    Mugrauer, M.

    2016-03-01

    The Cassegrain-Teleskop-Kamera (CTK-II) and the Refraktor-Teleskop-Kamera (RTK) are two CCD-imagers which are operated at the 25 cm Cassegrain and 20 cm refractor auxiliary telescopes of the University Observatory Jena. This article describes the main characteristics of these instruments. The properties of the CCD-detectors, the astrometry, the image quality, and the detection limits of both CCD-cameras, as well as some results of ongoing observing projects, carried out with these instruments, are presented. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University.

  4. Scintillating screen CCD camera using fast analog on-chip storage for time-resolved x-ray absorption spectroscopy

    Science.gov (United States)

    Koch, Andreas; Hagelstein, Michael; San Miguel, Alfonso; Fontaine, Alain; Ressler, Thorsten

    1995-03-01

    Serial readout of cooled, linear Si-photodiode arrays or CCDs offer a high dynamic range but only at moderate pixel readout rates. Recording spectroscopic information, i.e. 1D images, requires only a few sensitive lines of a 2D CCD array. A camera is presented where the unexposed part of the CCD is used as a buffer to store successive spectra with high frame rates. In this 'streak mode' the time resolution for data acquisition depends only on the line shift time of the CCD and no longer on the slow pixel readout time. A frame rate of 10 kHz for X-ray absorption spectra has been achieved. The CCD is part of an X-ray camera consisting of a scintillating screen lens-coupled to the CCD. The camera provides a high dynamic range of 17 bit, a spatial resolution of 60 micrometers (FWHM) and a high detective quantum efficiency of > 40% for x- ray energies between 4 keV and 25 keV. The camera is used for time- resolved energy-dispersive XAFS (X-ray Absorption Fine Structure) experiments. This technique permits the study of time-dependent variations of electronic properties and the local environment of atoms under induced external perturbation.

  5. Benchmarking of Back Thinned 512x512 X-ray CCD Camera Measurements with DEF X-ray film

    Science.gov (United States)

    Shambo, N. A.; Workman, J.; Kyrala, G.; Hurry, T.; Gonzales, R.; Evans, S. C.

    1999-11-01

    Using the Trident Laser Facility at Los Alamos National Laboratory 25-micron thick, 2mm diameter titanium disks were shot with a 527nm(green) laser light to measure x-ray yield. 1.0 mil and 0.5 mil Aluminum steps were used to test the linearity of the CCD Camera and DEF X-ray film was used to test the calibration of the CCD Camera response at 4.75keV. Both laser spot size and incident laser intensity were constrained to give constancy to the experimental data. This poster will discuss both the experimental design and results.

  6. Application of CCD Cameras to Investigations of Mixing on Boundaries of a Thermal Plasma Jet

    Institute of Scientific and Technical Information of China (English)

    J.HLINA; J.(S)ONSKY; J.(S)LECHTA

    2007-01-01

    Mixing of a thermal plasma jet with the surrounding atmosphere was studied using two CCD cameras (PCO SensiCam) situated detecting simultaneously the radiation of argon and nitrogen.The evaluation of image differences between two records showed that the location of regions on plasma jet boundaries characterised by stronger nitrogen radiation changes with the plasma flow rate.Close-to-laminar flow results in a small mixing rate and consequently low nitrogen optical emission on plasma jet boundaries.The increase of the flow rate leads to the formation of a relatively thick and stable layer on the boundaries characterised by strong nitrogen radiation.Further enhancement of the flow rate results in the formation of unstable regions of excited nitrogen molecules moving along the jet.

  7. Radiometric calibration of frame transfer CCD camera with uniform source system

    Science.gov (United States)

    Zhou, Jiankang; Shi, Rongbao; Chen, Yuheng; Zhou, Yuying; Shen, Weimin

    2010-08-01

    This paper presents a radiometric calibration method based on visibility function and uniform source system. The uniform system is mainly comprised of an integrating sphere and a monitoring silicon detector. The current of the silicon detector with a visibility function filter corresponds to the luminance at the exit port of integrating sphere through standard luminance meter transfer. The radiance at the camera entrance pupil is calculated for different solar zenith angles and Earth surface albedos by the MODTRAN atmospheric code. To simplify the calibration process, the radiance at its entrance pupil is integrated by visibility function. The shift smear of the frame transfer CCD is removed by the radiometric calibration and the amending ratio factor is introduced in the retrieving methods. The imaging experiment verifies the reliability of the calibration method and retrieves good quality image.

  8. Applications in radiation therapy of a scintillating screen viewed by a CCD camera

    CERN Document Server

    Schippers, J M; Luijk, P V

    2002-01-01

    A two-dimensional (2D) dosimetry system has been designed for position-sensitive dose-measurement applications in modern radiation therapy. The system consists of a scintillating screen (Gd sub 2 O sub 2 S : Tb), observed by a low-noise CCD camera with a long integration time. The system allows reliable and accurate simultaneous 2D imaging of therapeutic dose distributions in the scintillator with sub millimeter spatial resolution. This system has been applied successfully at different applications in radiation therapy. Results of dose measurements in a treatment modality using a scanning proton beam are reported. It is shown that a quick and reliable measurement can be done. The screen+CCD system has proven to perform accurate dosimetry in applications where beams with a small (1-5 mm) diameter are used and where absolute dosimetry by means of standard ionization chambers is not possible due to their relatively large size. For the routine measurements of the alignment of therapeutic beams with respect to the...

  9. Auto-measuring system of aero-camera lens focus using linear CCD

    Science.gov (United States)

    Zhang, Yu-ye; Zhao, Yu-liang; Wang, Shu-juan

    2014-09-01

    The automatic and accurate focal length measurement of aviation camera lens is of great significance and practical value. The traditional measurement method depends on the human eye to read the scribed line on the focal plane of parallel light pipe by means of reading microscope. The method is of low efficiency and the measuring results are influenced by artificial factors easily. Our method used linear array solid-state image sensor instead of reading microscope to transfer the imaging size of specific object to be electrical signal pulse width, and used computer to measure the focal length automatically. In the process of measurement, the lens to be tested placed in front of the object lens of parallel light tube. A couple of scribed line on the surface of the parallel light pipe's focal plane were imaging on the focal plane of the lens to be tested. Placed the linear CCD drive circuit on the image plane, the linear CCD can convert the light intensity distribution of one dimension signal into time series of electrical signals. After converting, a path of electrical signals is directly brought to the video monitor by image acquisition card for optical path adjustment and focusing. The other path of electrical signals is processed to obtain the pulse width corresponding to the scribed line by electrical circuit. The computer processed the pulse width and output focal length measurement result. Practical measurement results showed that the relative error was about 0.10%, which was in good agreement with the theory.

  10. Contrast reduction in digital images due to x-ray induced damage to a TV camera's CCD image receptor

    International Nuclear Information System (INIS)

    The CCD image receptor in a monochrome TV camera was irradiated in the dark with a single-phase 80 kVp narrow beam carrying an additional 0.5 mm Al filter. It was found that the CCD responded to the x-rays with a transient signal which would reach a maximum value at about 70 mR per image frame. The signal's contrast would reach a maximum of about 7%, but was detectable at much lower exposure rates. Continuous irradiation of the CCD image receptor created a 'lesion' at the point of incidence that remained after the x-ray beam was switched off. This signal seemed to be due to permanent damage to the CCD and could be detected after a cumulative exposure of less than 20 R. It was shown that such damage could be created much more effectively if the TV camera was switched off rather than on and the maximum contrast was achieved with about 75 R and 220 R respectively. The maximum contrast achieved was about 8%. Further increase in the cumulative exposure of a particular location on the CCD image receptor was not investigated but it seemed reasonable that much higher contrast values could be reached if irradiation was continued. The latter damage described here was found to persist for at least several weeks and hence it will probably prevent any normal use of the TV camera in the future. (author)

  11. Color measurement in standard CIELAB coordinates using a 3CCD camera: correction for the influence of the light source

    Science.gov (United States)

    Corbalan-Fuertes, Montserrat; Millan, Maria S.; Yzuel, Maria J.

    2000-06-01

    We have analyzed the accuracy of the compensating performance of the white-balance mechanism of a 3CCD camera for the three common types of light--fluorescent (F), incandescent (I), and daylight (D). We study the behavior of the camera using the RGB and CIELAB coordinates for a wide set of color samples covering the visible spectrum. CIELAB coordinates are obtained from the tristimulus XYZ. Using linear methods, we obtain the XYZ values from the (RGB)CCD values acquired by a 3CCD camera. We propose two different approaches: the first is specific for each particular light source (F, I, and D); the second considers the equienergetic spectral light source as an approximation for white lighting. We measure the mean color difference in the CIELAB space under a change of illuminant and compare the results in order to evaluate the performance of the response of a 3CCD camera. The transformations that are specific for a given light source allow an improved response under change of illuminant in terms of color constancy.

  12. Establishment and Optimization of Rigorous Geometric Model of Push-broom Camera Using TDI CCD Arranged in an Alternating Pattern

    Directory of Open Access Journals (Sweden)

    MENG Weican

    2015-12-01

    Full Text Available Push-broom cameras using TDI CCD arranged in an alternating pattern are widely carried by typical high-resolution optical satellites in order to obtain high space resolution and enough strip width. For this kind of cameras, several TDI CCD are arranged in an alternating pattern in two lines on the focal plane and push-broom imaging mode is always adopted. Imaging principle and characteristic of this kind of camera is introduced. Exterior parameters of TDI CCD are modeled together based on their same values in any instant of time and an integrated geometric model is finally established. Error compensation methods are designed to remove exterior error and interior error based on this integrated geometric model. A series of tests are designed to verify models and methods proposed in this paper using original image of TH-1 Satellite HR Camera whose detectors are divided into 8 modules arranged in an alternating pattern. As the results, the imaging geometry of this kind of camera can be rigorously described by this integral geometrical model. The positioning accuracy can be obviously improved by our exterior error compensation method, however, different residual error would be remained for different TDI CCD. The positioning accuracy will not be obviously improved while systematic errors of different TDI CCD can be effectively removed by the interior error compensation method. 2 m positioning accuracy in X, Y and Z directions can be achieved and different systematic errors can be removed when both exterior and interior error were compensated. The same accuracy can be achieved in the other scenes when the calculated inner distortion parameters are adopted.

  13. Maximum-likelihood scintillation detection for EM-CCD based gamma cameras

    International Nuclear Information System (INIS)

    Gamma cameras based on charge-coupled devices (CCDs) coupled to continuous scintillation crystals can combine a good detection efficiency with high spatial resolutions with the aid of advanced scintillation detection algorithms. A previously developed analytical multi-scale algorithm (MSA) models the depth-dependent light distribution but does not take statistics into account. Here we present and validate a novel statistical maximum-likelihood algorithm (MLA) that combines a realistic light distribution model with an experimentally validated statistical model. The MLA was tested for an electron multiplying CCD optically coupled to CsI(Tl) scintillators of different thicknesses. For 99mTc imaging, the spatial resolution (for perpendicular and oblique incidence), energy resolution and signal-to-background counts ratio (SBR) obtained with the MLA were compared with those of the MSA. Compared to the MSA, the MLA improves the energy resolution by more than a factor of 1.6 and the SBR is enhanced by more than a factor of 1.3. For oblique incidence (approximately 450), the depth-of-interaction corrected spatial resolution is improved by a factor of at least 1.1, while for perpendicular incidence the MLA resolution does not consistently differ significantly from the MSA result for all tested scintillator thicknesses. For the thickest scintillator (3 mm, interaction probability 66% at 141 keV) a spatial resolution (perpendicular incidence) of 147 μm full width at half maximum (FWHM) was obtained with an energy resolution of 35.2% FWHM. These results of the MLA were achieved without prior calibration of scintillations as is needed for many statistical scintillation detection algorithms. We conclude that the MLA significantly improves the gamma camera performance compared to the MSA.

  14. Optical Readout of a Two Phase Liquid Argon TPC using CCD Camera and TGEMs

    CERN Document Server

    Mavrokoridis, K; Carroll, J; Lazos, M; McCormick, K J; Smith, N A; Touramanis, C; Walker, J

    2014-01-01

    This paper presents a preliminary study into the use of CCDs to image secondary scintillation light generated by Thick Gas Electron Multipliers (TGEMs) in a two phase LAr TPC. A Sony ICX285AL CCD chip was mounted above a double TGEM in the gas phase of a 40 litre two-phase LAr TPC with the majority of the camera electronics positioned externally via a feedthrough. An Am-241 source was mounted on a rotatable motion feedthrough allowing the positioning of the alpha source either inside or outside of the field cage. Developed for and incorporated into the TPC design was a novel high voltage feedthrough featuring LAr insulation. Furthermore, a range of webcams were tested for operation in cryogenics as an internal detector monitoring tool. Of the range of webcams tested the Microsoft HD-3000 (model no:1456) webcam was found to be superior in terms of noise and lowest operating temperature. In ambient temperature and atmospheric pressure 1 ppm pure argon gas, the TGEM gain was approximately 1000 and using a 1 msec...

  15. Research on detecting heterogeneous fibre from cotton based on linear CCD camera

    Science.gov (United States)

    Zhang, Xian-bin; Cao, Bing; Zhang, Xin-peng; Shi, Wei

    2009-07-01

    The heterogeneous fibre in cotton make a great impact on production of cotton textile, it will have a bad effect on the quality of product, thereby affect economic benefits and market competitive ability of corporation. So the detecting and eliminating of heterogeneous fibre is particular important to improve machining technics of cotton, advance the quality of cotton textile and reduce production cost. There are favorable market value and future development for this technology. An optical detecting system obtains the widespread application. In this system, we use a linear CCD camera to scan the running cotton, then the video signals are put into computer and processed according to the difference of grayscale, if there is heterogeneous fibre in cotton, the computer will send an order to drive the gas nozzle to eliminate the heterogeneous fibre. In the paper, we adopt monochrome LED array as the new detecting light source, it's lamp flicker, stability of luminous intensity, lumens depreciation and useful life are all superior to fluorescence light. We analyse the reflection spectrum of cotton and various heterogeneous fibre first, then select appropriate frequency of the light source, we finally adopt violet LED array as the new detecting light source. The whole hardware structure and software design are introduced in this paper.

  16. Tests of a new CCD-camera based neutron radiography detector system at the reactor stations in Munich and Vienna

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, E.; Pleinert, H. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Schillinger, B. [Technische Univ. Muenchen (Germany); Koerner, S. [Atominstitut der Oesterreichischen Universitaeten, Vienna (Austria)

    1997-09-01

    The performance of the new neutron radiography detector designed at PSI with a cooled high sensitive CCD-camera was investigated under real neutronic conditions at three beam ports of two reactor stations. Different converter screens were applied for which the sensitivity and the modulation transfer function (MTF) could be obtained. The results are very encouraging concerning the utilization of this detector system as standard tool at the radiography stations at the spallation source SINQ. (author) 3 figs., 5 refs.

  17. MOA-cam3: a wide-field mosaic CCD camera for a gravitational microlensing survey in New Zealand

    CERN Document Server

    Sako, T; Sasaki, M; Okajima, K; Abe, F; Bond, I A; Hearnshaw, J B; Itow, Y; Kamiya, K; Kilmartin, P M; Masuda, K; Matsubara, Y; Muraki, Y; Rattenbury, N J; Sullivan, D J; Sumi, T; Tristram, P; Yanagisawa, T; Yock, P C M

    2008-01-01

    We have developed a wide-field mosaic CCD camera, MOA-cam3, mounted at the prime focus of the Microlensing Observations in Astrophysics (MOA) 1.8-m telescope. The camera consists of ten E2V CCD4482 chips, each having 2kx4k pixels, and covers a 2.2 deg^2 field of view with a single exposure. The optical system is well optimized to realize uniform image quality over this wide field. The chips are constantly cooled by a cryocooler at -80C, at which temperature dark current noise is negligible for a typical 1-3 minute exposure. The CCD output charge is converted to a 16-bit digital signal by the GenIII system (Astronomical Research Cameras Inc.) and readout is within 25 seconds. Readout noise of 2--3 ADU (rms) is also negligible. We prepared a wide-band red filter for an effective microlensing survey and also Bessell V, I filters for standard astronomical studies. Microlensing studies have entered into a new era, which requires more statistics, and more rapid alerts to catch exotic light curves. Our new system is...

  18. Classification of volcanic ash particles from Sakurajima volcano using CCD camera image and cluster analysis

    Science.gov (United States)

    Miwa, T.; Shimano, T.; Nishimura, T.

    2012-12-01

    Quantitative and speedy characterization of volcanic ash particle is needed to conduct a petrologic monitoring of ongoing eruption. We develop a new simple system using CCD camera images for quantitatively characterizing ash properties, and apply it to volcanic ash collected at Sakurajima. Our method characterizes volcanic ash particles by 1) apparent luminance through RGB filters and 2) a quasi-fractal dimension of the shape of particles. Using a monochromatic CCD camera (Starshoot by Orion Co. LTD.) attached to a stereoscopic microscope, we capture digital images of ash particles that are set on a glass plate under which white colored paper or polarizing plate is set. The images of 1390 x 1080 pixels are taken through three kinds of color filters (Red, Green and Blue) under incident-light and transmitted-light through polarizing plate. Brightness of the light sources is set to be constant, and luminance is calibrated by white and black colored papers. About fifteen ash particles are set on the plate at the same time, and their images are saved with a bit map format. We first extract the outlines of particles from the image taken under transmitted-light through polarizing plate. Then, luminances for each color are represented by 256 tones at each pixel in the particles, and the average and its standard deviation are calculated for each ash particle. We also measure the quasi-fractal dimension (qfd) of ash particles. We perform box counting that counts the number of boxes which consist of 1×1 and 128×128 pixels that catch the area of the ash particle. The qfd is estimated by taking the ratio of the former number to the latter one. These parameters are calculated by using software R. We characterize volcanic ash from Showa crater of Sakurajima collected in two days (Feb 09, 2009, and Jan 13, 2010), and apply cluster analyses. Dendrograms are formed from the qfd and following four parameters calculated from the luminance: Rf=R/(R+G+B), G=G/(R+G+B), B=B/(R+G+B), and

  19. Developing a CCD camera with high spatial resolution for RIXS in the soft X-ray range

    Science.gov (United States)

    Soman, M. R.; Hall, D. J.; Tutt, J. H.; Murray, N. J.; Holland, A. D.; Schmitt, T.; Raabe, J.; Schmitt, B.

    2013-12-01

    The Super Advanced X-ray Emission Spectrometer (SAXES) at the Swiss Light Source contains a high resolution Charge-Coupled Device (CCD) camera used for Resonant Inelastic X-ray Scattering (RIXS). Using the current CCD-based camera system, the energy-dispersive spectrometer has an energy resolution (E/ΔE) of approximately 12,000 at 930 eV. A recent study predicted that through an upgrade to the grating and camera system, the energy resolution could be improved by a factor of 2. In order to achieve this goal in the spectral domain, the spatial resolution of the CCD must be improved to better than 5 μm from the current 24 μm spatial resolution (FWHM). The 400 eV-1600 eV energy X-rays detected by this spectrometer primarily interact within the field free region of the CCD, producing electron clouds which will diffuse isotropically until they reach the depleted region and buried channel. This diffusion of the charge leads to events which are split across several pixels. Through the analysis of the charge distribution across the pixels, various centroiding techniques can be used to pinpoint the spatial location of the X-ray interaction to the sub-pixel level, greatly improving the spatial resolution achieved. Using the PolLux soft X-ray microspectroscopy endstation at the Swiss Light Source, a beam of X-rays of energies from 200 eV to 1400 eV can be focused down to a spot size of approximately 20 nm. Scanning this spot across the 16 μm square pixels allows the sub-pixel response to be investigated. Previous work has demonstrated the potential improvement in spatial resolution achievable by centroiding events in a standard CCD. An Electron-Multiplying CCD (EM-CCD) has been used to improve the signal to effective readout noise ratio achieved resulting in a worst-case spatial resolution measurement of 4.5±0.2 μm and 3.9±0.1 μm at 530 eV and 680 eV respectively. A method is described that allows the contribution of the X-ray spot size to be deconvolved from these

  20. Developing a CCD camera with high spatial resolution for RIXS in the soft X-ray range

    Energy Technology Data Exchange (ETDEWEB)

    Soman, M.R., E-mail: m.r.soman@open.ac.uk [e2v centre for electronic imaging, The Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom); Hall, D.J.; Tutt, J.H.; Murray, N.J.; Holland, A.D. [e2v centre for electronic imaging, The Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom); Schmitt, T.; Raabe, J.; Schmitt, B. [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)

    2013-12-11

    The Super Advanced X-ray Emission Spectrometer (SAXES) at the Swiss Light Source contains a high resolution Charge-Coupled Device (CCD) camera used for Resonant Inelastic X-ray Scattering (RIXS). Using the current CCD-based camera system, the energy-dispersive spectrometer has an energy resolution (E/ΔE) of approximately 12,000 at 930 eV. A recent study predicted that through an upgrade to the grating and camera system, the energy resolution could be improved by a factor of 2. In order to achieve this goal in the spectral domain, the spatial resolution of the CCD must be improved to better than 5 µm from the current 24 µm spatial resolution (FWHM). The 400 eV–1600 eV energy X-rays detected by this spectrometer primarily interact within the field free region of the CCD, producing electron clouds which will diffuse isotropically until they reach the depleted region and buried channel. This diffusion of the charge leads to events which are split across several pixels. Through the analysis of the charge distribution across the pixels, various centroiding techniques can be used to pinpoint the spatial location of the X-ray interaction to the sub-pixel level, greatly improving the spatial resolution achieved. Using the PolLux soft X-ray microspectroscopy endstation at the Swiss Light Source, a beam of X-rays of energies from 200 eV to 1400 eV can be focused down to a spot size of approximately 20 nm. Scanning this spot across the 16 µm square pixels allows the sub-pixel response to be investigated. Previous work has demonstrated the potential improvement in spatial resolution achievable by centroiding events in a standard CCD. An Electron-Multiplying CCD (EM-CCD) has been used to improve the signal to effective readout noise ratio achieved resulting in a worst-case spatial resolution measurement of 4.5±0.2 μm and 3.9±0.1 μm at 530 eV and 680 eV respectively. A method is described that allows the contribution of the X-ray spot size to be deconvolved from these

  1. Sensors for 3D Imaging: Metric Evaluation and Calibration of a CCD/CMOS Time-of-Flight Camera

    Directory of Open Access Journals (Sweden)

    Fulvio Rinaudo

    2009-12-01

    Full Text Available 3D imaging with Time-of-Flight (ToF cameras is a promising recent technique which allows 3D point clouds to be acquired at video frame rates. However, the distance measurements of these devices are often affected by some systematic errors which decrease the quality of the acquired data. In order to evaluate these errors, some experimental tests on a CCD/CMOS ToF camera sensor, the SwissRanger (SR-4000 camera, were performed and reported in this paper. In particular, two main aspects are treated: the calibration of the distance measurements of the SR-4000 camera, which deals with evaluation of the camera warm up time period, the distance measurement error evaluation and a study of the influence on distance measurements of the camera orientation with respect to the observed object; the second aspect concerns the photogrammetric calibration of the amplitude images delivered by the camera using a purpose-built multi-resolution field made of high contrast targets.

  2. Sensors for 3D Imaging: Metric Evaluation and Calibration of a CCD/CMOS Time-of-Flight Camera.

    Science.gov (United States)

    Chiabrando, Filiberto; Chiabrando, Roberto; Piatti, Dario; Rinaudo, Fulvio

    2009-01-01

    3D imaging with Time-of-Flight (ToF) cameras is a promising recent technique which allows 3D point clouds to be acquired at video frame rates. However, the distance measurements of these devices are often affected by some systematic errors which decrease the quality of the acquired data. In order to evaluate these errors, some experimental tests on a CCD/CMOS ToF camera sensor, the SwissRanger (SR)-4000 camera, were performed and reported in this paper. In particular, two main aspects are treated: the calibration of the distance measurements of the SR-4000 camera, which deals with evaluation of the camera warm up time period, the distance measurement error evaluation and a study of the influence on distance measurements of the camera orientation with respect to the observed object; the second aspect concerns the photogrammetric calibration of the amplitude images delivered by the camera using a purpose-built multi-resolution field made of high contrast targets.

  3. Self-shunted streamer chamber spectrometer with CCD video cameras for studying pion interactions with light nuclei at energies below the Δ-resonance

    International Nuclear Information System (INIS)

    A description is presented of the detector system (a self-shunted streamer chamber in a magnetic field, equipped with two CCD video cameras) developed by the DUBTO collaboration for studying pion interactions with light nuclei at the JINR phasotron

  4. Laboratory characterization of a CCD camera system for retrieval of bi-directional reflectance distribution function

    Science.gov (United States)

    Nandy, Prabal; Thome, Kurtis J.; Biggar, Stuart F.

    1999-12-01

    The Remote Sensing Group of the Optical Science Center at the University of Arizona has developed a four-band, multi- spectral, wide-angle, imaging radiometer for the retrieval of the bi-directional reflectance distribution function (BRDF) for vicarious calibration applications. The system consists of a fisheye lens with four interference filters centered at 470 nm, 575 nm, 660 nm, and 835 nm for spectral selection and an astronomical grade 1024 X 1024-pixel, silicon CCD array. Data taken by the system fit in the array as a nominally 0.2 degree per pixel image. This imaging radiometer system has been used in support of the calibration of Landsat-5 and SPOT- satellite sensors. This paper presents the results of laboratory characterization of the system to determine linearity of the detector, point spread function (PSF) and polarization effects. The linearity study was done on detector array without the lens, using a spherical-integrating source with a 1.5-mm aperture. This aperture simulates a point source for distances larger than 60 cm. Data were collected as both a function of exposure time and distance from the source. The results of these measurements indicate that each detector of the array is linear to better than 0.5%. Assuming a quadratic response improves this fit to better than 0.1% over 88% of the upper end of the detector's dynamic range. The point spread function (PSF) of the lens system was measured using the sphere source and aperture with the full camera system operated at a distance of 700 mm from the source, thus the aperture subtends less than the field of view of one pixel. The PSF was measured for several field angles and the signal level was found to fall to less than 1% of the peak signal within 1.5-degrees (10 pixels) for the on-axis case. The effect of this PSF on the retrieval of modeled BRDFs is shown to be less than 0.2% out to view angles of 70 degrees. The final test presented is one to assess the polarization effects of the lens

  5. MISR Level 1A CCD Science data, all cameras V002

    Data.gov (United States)

    National Aeronautics and Space Administration — This is the Reformatted Annotated Level 1A product for the CCD science data. The data numbers (DN) have been commuted from 12-bit numbers to 16-bit byte aligned...

  6. A toolkit for the characterization of CCD cameras for transmission electron microscopy

    NARCIS (Netherlands)

    Vulovic, M.; Rieger, B.; Van Vliet, L.J.; Koster, A.J.; Ravelli, R.B.G.

    2009-01-01

    Charge-coupled devices (CCD) are nowadays commonly utilized in transmission electron microscopy (TEM) for applications in life sciences. Direct access to digitized images has revolutionized the use of electron microscopy, sparking developments such as automated collection of tomographic data, focal

  7. A positioning model of a two CCD camera coordinate system with an alternate-four-matrix look-up table algorithm

    Science.gov (United States)

    Lin, Chern-Sheng; Chen, Chia-Tse; Wei, Tzu-Chi; Chen, Wei-Lung; Chang, Chia-Chang

    2010-12-01

    This study proposes a novel positioning model of a two CCD camera coordinate system with an alternate-four-matrix (AFM) look-up table (LUT) algorithm. Two CCD cameras are set on both sides of a large scale screen and used to aid the position measures of targets. The coordinate position of the object in a specified space can be obtained by using different viewing angles of the two cameras and the AFMLUT method. The right camera is in charge of detecting the intermediate block near the right side and the dead zone of the left camera, using the first and the second matrix LUTs. The left camera is in charge of detecting the other parts, using the third and the fourth matrix LUTs. The results indicate that this rapid mapping and four matrix memory allocation method has good accuracy (positioning error <2%) and stability when operating a human-machine interface system.

  8. Implementation of a parallel-beam optical-CT apparatus for three-dimensional radiation dosimetry using a high-resolution CCD camera

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Wen-Tzeng [Department of Computer Science and Information Engineering, Minghsin University of Science and Technology, Taiwan, ROC (China); Chen, Chin-Hsing [Department of Management Information Systems, Central Taiwan University of Science and Technology, Taichung, Taiwan, ROC (China); Hung, Chao-Nan; Tuan, Chiu-Ching [Graduate Institute of Computer and Communication Engineering, National Taipei University of Technology, Taiwan, ROC (China); Chang, Yuan-Jen, E-mail: ronchang@ctust.edu.tw [Department of Management Information Systems, Central Taiwan University of Science and Technology, Taichung, Taiwan, ROC (China); Institute of Biomedical Engineering and Materials Science, Central Taiwan University of Science and Technology, Taichung, Taiwan, ROC (China)

    2015-06-01

    In this study, a charge-coupled device (CCD) camera with 2-megapixel (1920×1080-pixel) and 12-bit resolution was developed for optical computed tomography(optical CT). The signal-to-noise ratio (SNR) of our system was 30.12 dB, better than that of commercially available CCD cameras (25.31 dB). The 50% modulation transfer function (MTF50) of our 1920×1080-pixel camera gave a line width per picture height (LW/PH) of 745, which is 73% of the diffraction-limited resolution. Compared with a commercially available 1-megapixel CCD camera (1296×966-pixel) with a LW/PH=358 and 46.6% of the diffraction-limited resolution, our camera system provided higher spatial resolution and better image quality. The NIPAM gel dosimeter was used to evaluate the optical CT with a 2-megapixel CCD. A clinical five-field irradiation treatment plan was generated using the Eclipse planning system (Varian Corp., Palo Alto, CA, USA). The gel phantom was irradiated using a 6-MV Varian Clinac IX linear accelerator (Varian). The measured NIPAM gel dose distributions and the calculated dose distributions, generated by the treatment planning software (TPS), were compared using the 3% dose-difference and 3 mm distance-to-agreement criteria. The gamma pass rate was as high as 98.2% when 2-megapixel CCD camera was used in optical CT. However, the gamma pass rate was only 96.0% when a commercially available 1-megapixel CCD camera was used. - Highlights: • An optical CT system with a 2-megapixel CCD showed high uniformity of reconstructed images of the gel phantom. • The gamma pass rate was as high as 98.2% with the 3% dose difference and 3 mm dose to agreement criteria. • Our CCD with 12-bit information could guarantee better SNR performance, of 30.12 dB. • Our 2-megapixel CCD camera gave a LW/PH of 745, 73% of the diffraction-limited resolution.

  9. Dynamic imaging with a triggered and intensified CCD camera system in a high-intensity neutron beam

    Science.gov (United States)

    Vontobel, P.; Frei, G.; Brunner, J.; Gildemeister, A. E.; Engelhardt, M.

    2005-04-01

    When time-dependent processes within metallic structures should be inspected and visualized, neutrons are well suited due to their high penetration through Al, Ag, Ti or even steel. Then it becomes possible to inspect the propagation, distribution and evaporation of organic liquids as lubricants, fuel or water. The principle set-up of a suited real-time system was implemented and tested at the radiography facility NEUTRA of PSI. The highest beam intensity there is 2×107 cm s, which enables to observe sequences in a reasonable time and quality. The heart of the detection system is the MCP intensified CCD camera PI-Max with a Peltier cooled chip (1300×1340 pixels). The intensifier was used for both gating and image enhancement, where as the information was accumulated over many single frames on the chip before readout. Although, a 16-bit dynamic range is advertised by the camera manufacturers, it must be less due to the inherent noise level from the intensifier. The obtained result should be seen as the starting point to go ahead to fit the different requirements of car producers in respect to fuel injection, lubricant distribution, mechanical stability and operation control. Similar inspections will be possible for all devices with repetitive operation principle. Here, we report about two measurements dealing with the lubricant distribution in a running motorcycle motor turning at 1200 rpm. We were monitoring the periodic stationary movements of piston, valves and camshaft with a micro-channel plate intensified CCD camera system (PI-Max 1300RB, Princeton Instruments) triggered at exactly chosen time points.

  10. Digital image measurement of specimen deformation based on CCD cameras and Image J software: an application to human pelvic biomechanics

    Science.gov (United States)

    Jia, Yongwei; Cheng, Liming; Yu, Guangrong; Lou, Yongjian; Yu, Yan; Chen, Bo; Ding, Zuquan

    2008-03-01

    A method of digital image measurement of specimen deformation based on CCD cameras and Image J software was developed. This method was used to measure the biomechanics behavior of human pelvis. Six cadaveric specimens from the third lumbar vertebra to the proximal 1/3 part of femur were tested. The specimens without any structural abnormalities were dissected of all soft tissue, sparing the hip joint capsules and the ligaments of the pelvic ring and floor. Markers with black dot on white background were affixed to the key regions of the pelvis. Axial loading from the proximal lumbar was applied by MTS in the gradient of 0N to 500N, which simulated the double feet standing stance. The anterior and lateral images of the specimen were obtained through two CCD cameras. Based on Image J software, digital image processing software, which can be freely downloaded from the National Institutes of Health, digital 8-bit images were processed. The procedure includes the recognition of digital marker, image invert, sub-pixel reconstruction, image segmentation, center of mass algorithm based on weighted average of pixel gray values. Vertical displacements of S1 (the first sacral vertebrae) in front view and micro-angular rotation of sacroiliac joint in lateral view were calculated according to the marker movement. The results of digital image measurement showed as following: marker image correlation before and after deformation was excellent. The average correlation coefficient was about 0.983. According to the 768 × 576 pixels image (pixel size 0.68mm × 0.68mm), the precision of the displacement detected in our experiment was about 0.018 pixels and the comparatively error could achieve 1.11\\perthou. The average vertical displacement of S1 of the pelvis was 0.8356+/-0.2830mm under vertical load of 500 Newtons and the average micro-angular rotation of sacroiliac joint in lateral view was 0.584+/-0.221°. The load-displacement curves obtained from our optical measure system

  11. Requisites for the remote-controlled wide-view CCD camera unit for natural orifice transluminal endoscopic surgery placed in the intraperitoneal cavity.

    Science.gov (United States)

    Ohdaira, Takeshi; Yasuda, Yoshikazu; Hashizume, Makoto

    2010-04-01

    In natural orifice transluminal endoscopic surgery (NOTES) using a single endoscope, the visual field moves unstably and a wide blind space is formed. We used wireless two wireless CCD cameras (270,000 and 380,000 pixels) placed on the abdominal wall of pigs and a conventional endoscope (410,000 pixels) at the same time to assess whether it was possible to observe the entire process of sigmoidectomy by NOTES. The titanium dioxide-coated lens was used as an antifogging apparatus. To control the CCD image frames, a magnetic body was affixed to the back of the CCD camera unit. To select a suitable visual-transmitter, three frequency bands were assessed: 0.07 GHz, 1.2 GHz, and 2.4 GHz. The cameras showed good performance for monitoring all procedures of the sigmoidectomy. The magnetic force most suitable to control the cameras was found to be 360 mT, and the best transmission frequency was 1.2 GHz. The battery could be used for up to 4 hours with intermittent use. The issue of lens fogging could be resolved by a water supply into the anal canal and a more than 12-hour ultraviolet irradiation. We verified that the CCD camera with the titanium dioxide-coated lens may be useful as the second eye in NOTES. PMID:20437343

  12. LED characterization for development of on-board calibration unit of CCD-based advanced wide-field sensor camera of Resourcesat-2A

    Science.gov (United States)

    Chatterjee, Abhijit; Verma, Anurag

    2016-05-01

    The Advanced Wide Field Sensor (AWiFS) camera caters to high temporal resolution requirement of Resourcesat-2A mission with repeativity of 5 days. The AWiFS camera consists of four spectral bands, three in the visible and near IR and one in the short wave infrared. The imaging concept in VNIR bands is based on push broom scanning that uses linear array silicon charge coupled device (CCD) based Focal Plane Array (FPA). On-Board Calibration unit for these CCD based FPAs is used to monitor any degradation in FPA during entire mission life. Four LEDs are operated in constant current mode and 16 different light intensity levels are generated by electronically changing exposure of CCD throughout the calibration cycle. This paper describes experimental setup and characterization results of various flight model visible LEDs (λP=650nm) for development of On-Board Calibration unit of Advanced Wide Field Sensor (AWiFS) camera of RESOURCESAT-2A. Various LED configurations have been studied to meet dynamic range coverage of 6000 pixels silicon CCD based focal plane array from 20% to 60% of saturation during night pass of the satellite to identify degradation of detector elements. The paper also explains comparison of simulation and experimental results of CCD output profile at different LED combinations in constant current mode.

  13. Rayleigh Laser Guide Star Systems UnISIS Bow Tie Shutter and CCD39 Wavefront Camera

    CERN Document Server

    Thompson, L A; Crawford, S L; Leach, R W; Thompson, Laird A.; Teare, Scott W.; Crawford, Samuel L.; Leach, Robert W.

    2002-01-01

    Laser guide star systems based on Rayleigh scattering require some means to deal with the flash of low altitude laser light that follows immediately after each laser pulse. These systems also need a fast shutter to isolate the high altitude portion of the focused laser beam to make it appear star-like to the wavefront sensor. We describe how these tasks are accomplished with UnISIS, the Rayleigh laser guided adaptive optics system at the Mt. Wilson Observatory 2.5-m telescope. We use several methods: a 10,000 RPM rotating disk, dichroics, a fast sweep and clear mode of the CCD readout electronics on a 10 $\\mu$s timescale, and a Pockel's cell shutter system. The Pockel's cell shutter would be conventional in design if the laser light were naturally polarized, but the UnISIS 351 nm laser is unpolarized. So we have designed and put into operation a dual Pockel's cell shutter in a unique bow tie arrangement.

  14. On Relativistic Disk Spectroscopy in Compact Objects with X-ray CCD Cameras

    Science.gov (United States)

    Miller, J. M.; D'Aì, A.; Bautz, M. W.; Bhattacharyya, S.; Burrows, D. N.; Cackett, E. M.; Fabian, A. C.; Freyberg, M. J.; Haberl, F.; Kennea, J.; Nowak, M. A.; Reis, R. C.; Strohmayer, T. E.; Tsujimoto, M.

    2010-12-01

    X-ray charge-coupled devices (CCDs) are the workhorse detectors of modern X-ray astronomy. Typically covering the 0.3-10.0 keV energy range, CCDs are able to detect photoelectric absorption edges and K shell lines from most abundant metals. New CCDs also offer resolutions of 30-50 (E/ΔE), which is sufficient to detect lines in hot plasmas and to resolve many lines shaped by dynamical processes in accretion flows. The spectral capabilities of X-ray CCDs have been particularly important in detecting relativistic emission lines from the inner disks around accreting neutron stars and black holes. One drawback of X-ray CCDs is that spectra can be distorted by photon "pile-up," wherein two or more photons may be registered as a single event during one frame time. We have conducted a large number of simulations using a statistical model of photon pile-up to assess its impacts on relativistic disk line and continuum spectra from stellar-mass black holes and neutron stars. The simulations cover the range of current X-ray CCD spectrometers and operational modes typically used to observe neutron stars and black holes in X-ray binaries. Our results suggest that severe photon pile-up acts to falsely narrow emission lines, leading to falsely large disk radii and falsely low spin values. In contrast, our simulations suggest that disk continua affected by severe pile-up are measured to have falsely low flux values, leading to falsely small radii and falsely high spin values. The results of these simulations and existing data appear to suggest that relativistic disk spectroscopy is generally robust against pile-up when this effect is modest.

  15. Experimental comparison of the high-speed imaging performance of an EM-CCD and sCMOS camera in a dynamic live-cell imaging test case.

    Directory of Open Access Journals (Sweden)

    Hope T Beier

    Full Text Available The study of living cells may require advanced imaging techniques to track weak and rapidly changing signals. Fundamental to this need is the recent advancement in camera technology. Two camera types, specifically sCMOS and EM-CCD, promise both high signal-to-noise and high speed (>100 fps, leaving researchers with a critical decision when determining the best technology for their application. In this article, we compare two cameras using a live-cell imaging test case in which small changes in cellular fluorescence must be rapidly detected with high spatial resolution. The EM-CCD maintained an advantage of being able to acquire discernible images with a lower number of photons due to its EM-enhancement. However, if high-resolution images at speeds approaching or exceeding 1000 fps are desired, the flexibility of the full-frame imaging capabilities of sCMOS is superior.

  16. Design of echelle spectrograph CCD camera%中阶梯光栅光谱仪CCD相机的设计

    Institute of Scientific and Technical Information of China (English)

    潘明忠; 刘玉娟; 陈少杰; 宋楠; 崔继承

    2012-01-01

    为了高精度采集中阶梯光栅光谱仪的谱图,设计了一种适用于中阶梯光栅光谱仪原理样机的高性能面阵CCD相机.首先,根据中阶梯光栅光谱仪的谱图特点和CCD芯片的特性,设计了面阵CCD相机的时序产生电路、驱动电路及数据采集处理电路,实现了面阵CCD相机的低噪声、高灵敏度以及高动态范围.然后,利用LabVIEW编写了CCD相机测试软件.最后,利用设计的面阵CCD相机对汞灯谱线进行了测试.结果表明:面阵CCD相机获取的二维谱图图像清晰、信噪比较高;经二维谱图还原后,可以得到标准的汞灯谱线.该相机性能稳定、可靠,满足中阶梯光栅光谱仪原理样机的研制要求.%To get the high accuracy 2-D spectra of a self-designed echelle spectrograph,a high performance area CCD camera was designed. Based on the characteristics of echelle spectrograph and CCD chip, the timing generator circuit, drive circuit and the data processing circuit for the CCD camera were developed,by which the low noise, high sensitivity and high dynamic rang were realized at the same time. Then, the test software of CCD camera was programmed with Lab VIEW. Finally, the 2-D spectra of a Hg lamp were tested by using the area CCD camera. The result demonstrates that the area CCD camera can get the sharp 2-D spectra with high SNR. After reducing the spectra of Hg lamp, the standar spectral line is obtained. This CCD camera is steady, reliable and meets the needs of echelle spectrograph completely.

  17. 一种新的CCD相机与激光相机的标定方法%A New Calibration Method for CCD Camera and Laser Camera

    Institute of Scientific and Technical Information of China (English)

    桑瑞娟

    2012-01-01

    In the intelligent robot' s navigation and positioning system, in order to get more comprehen- sive and accurate information, people generally use multiple sensors to get information, therefore fuse da- tas are needed, the major problem of the fusion of multiple sensors is the coordinates calibration between them. In consideration of the coordinate calibration between CCD camera and laser camera: firstly, the information of special points in the calibration object ject was built, secondly, the corners were detected plane were removed, finally the rotation matrix and was got, then the pane equation of the calibration ob- by harris method, the points which were not in the translation matrix were solved. The results show that%在智能机器人的导航定位系统中,为了得到的信息更加全面和准确,一般采用多种传感器共同获取信息,这就需要进行数据的融合,多传感器的联合标定是数据融合的关键问题。针对CCD相机和激光相机进行标定,首先采集标定靶特殊点的信息,建立标定靶平面方程,其次用harris角点检测算法检测角点,去除不符合平面方程的点,最后求解旋转矩阵和平移矩阵。实验结果表明,该方法能有效去除混合像素,标定结果更加准确。

  18. Thermoelastic Analysis of Hyper-X Camera Windows Suddenly Exposed to Mach 7 Stagnation Aerothermal Shock

    Science.gov (United States)

    Ko, William L.; Gong, Leslie

    2000-01-01

    To visually record the initial free flight event of the Hyper-X research flight vehicle immediately after separation from the Pegasus(registered) booster rocket, a video camera was mounted on the bulkhead of the adapter through which Hyper-X rides on Pegasus. The video camera was shielded by a protecting camera window made of heat-resistant quartz material. When Hyper-X separates from Pegasus, this camera window will be suddenly exposed to Mach 7 stagnation thermal shock and dynamic pressure loading (aerothermal loading). To examine the structural integrity, thermoelastic analysis was performed, and the stress distributions in the camera windows were calculated. The critical stress point where the tensile stress reaches a maximum value for each camera window was identified, and the maximum tensile stress level at that critical point was found to be considerably lower than the tensile failure stress of the camera window material.

  19. Investigation of temporal evolution and spatial distribution of dust creation events in DITS campaign using visible CCD cameras in Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Suk-Ho [Association EURATOM-CEA/Cadarache, IRFM/SIPP/GIPP, St. Paul les Durance 13108 (France)], E-mail: sukhhong@nfri.re.kr; Grisolia, Christian; Monier-Gabet, Pascale [Association EURATOM-CEA/Cadarache, IRFM/SIPP/GIPP, St. Paul les Durance 13108 (France)

    2009-06-15

    Images of wide-angle visible CCD cameras contain information on dust creation events (flaking) that occur during plasma operations. Due to the interaction with plasma, flakes entering into the plasma left straight line-like visible traces behind in the images. Analyzing these traces by image processing, the temporal evolution, spatial distribution, and statistics on dust creation events in DITS campaign in Tore Supra were obtained.

  20. High-resolution application of YAG:Ce and LuAG:Ce imaging detectors with a CCD X-ray camera

    Science.gov (United States)

    Touš, Jan; Horváth, Martin; Pína, Ladislav; Blažek, Karel; Sopko, Bruno

    2008-06-01

    A high-resolution CCD X-ray camera based on YAG:Ce or LuAG:Ce thin scintillators is presented. High-resolution in low-energy X-ray radiation is proved with several objects. The spatial resolution achieved in the images is about 1 μm. The high-resolution imaging system is a combination of a high-sensitivity digital CCD camera and an optical system with a thin scintillator-imaging screen. The screen can consist of YAG:Ce or LuAG:Ce inorganic scintillator [J.A. Mares, Radiat. Meas. 38 (2004) 353]. These materials have the advantages of mechanical and chemical stability and non-hygroscopicity. The high-resolution imaging system can be used with different types of radiation (X-ray, electrons, UV, and VUV [M. Nikl, Meas. Sci. Technol. 17 (2006) R37]). The objects used for the imaging tests are grids and small animals with features of several microns in size. The resolution capabilities were tested using different types of CCD cameras and scintillation imaging screens.

  1. Near infrared thermography by CCD cameras and application to first wall components of Tore Supra tokamak; Thermographie proche infrarouge par cameras CCD et application aux composants de premiere paroi du tokamak Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Moreau, F.

    1996-06-07

    In the Tokamak TORE-SUPRA, the plasma facing components absorbs and evacuate (active cooling) high power fluxes (up to 10 MW/m{sup 2}). Their thermal behavior study is essential for the success of controlled thermonuclear fusion line. The first part is devoted to the study of power deposition on the TORE-SUPRA actively cooled limiters. A model of power deposition on one of the limiters is developed. It takes into account the magnetic topology and a description of the plasma edge. The model is validated with experimental calorimetric data obtained during a series of shots. This will allow to compare the surface temperature measurements with the predicted ones. The main purpose of this thesis was to evaluate and develop a new temperature measurement system. It works in the near infrared range (890 nm) and is designed to complete the existing thermographic diagnostic of TORE-SUPRA. By using the radiation laws (for a blackbody and the plasma) and the laboratory calibration one can estimate the surface temperature of the observed object. We evaluate the performances and limits of such a device in the harsh conditions encountered in a Tokamak environment. On the one hand, in a quasi ideal situation, this analysis shows that the range of measurements is 600 deg. C to 2500 deg. C. On the other hand, when one takes into account of the plasma radiation (with an averaged central plasma density of 6.10{sup 19} m{sup -3}), we find that the minimum surface temperature rise to 900 deg. C instead of 700 deg. C. In the near future, according to the development of IR-CCD cameras working in the near infrared range up to 2 micrometers, we will be able to keep the good spatial resolution with an improved lower limit for the temperature down to 150 deg. C. The last section deals with a number of computer tools to process the images obtained from experiments on TORE-SUPRA. A pattern recognition application was developed to detect a complex plasma iso-intensity structure. 87 refs.

  2. 传输型CCD相机成像分辨率自动测试研究%Research on automatic testing of image resolution of transmission CCD camera

    Institute of Scientific and Technical Information of China (English)

    王锋; 高亚飞

    2013-01-01

    对CCD相机成像分辨率自动测试方法进行了研究,测试方案中改进设计了照相分辨率靶标,开展了数据分析处理,通过软硬件结合实现了对CCD相机整机分辨率的自动测试,结果数据经过专业测试比对确认有效。实验结果表明,方法客观、准确,能够避免以往人工测试分辨率带来的主观因素影响,具有很高的实用性。%The automatic testing method of an image resolution of CCD camera is researched. The photo resolution drone design is improved in the testing project. The data analyzing and processing is carried out,and the automatic testing of CCD camera resolution is realized through the combination of hardware and software. The effectiveness of the result data is verified by professional testing. The experiment results show that the method is impersonality and accurate,it can avoid the affect of subjec-tive factors brought by manual testing resolution,and has prominence practicability.

  3. Extrapolation of contrail investigations by LIDAR to larger scale measurements. Analysis and calibration of CCD camera and satellite images

    Energy Technology Data Exchange (ETDEWEB)

    Sussmann, R.; Homburg, F.; Freudenthaler, V.; Jaeger, H. [Frauenhofer Inst. fuer Atmosphaerische Umweltforschung, Garmisch-Partenkirchen (Germany)

    1997-12-31

    The CCD image of a persistent contrail and the coincident LIDAR measurement are presented. To extrapolate the LIDAR derived optical thickness to the video field of view an anisotropy correction and calibration has to be performed. Observed bright halo components result from highly regular oriented hexagonal crystals with sizes of 200 {mu}m-2 mm. This explained by measured ambient humidities below the formation threshold of natural cirrus. Optical thickness from LIDAR shows significant discrepancies to the result from coincident NOAA-14 data. Errors result from anisotropy correction and parameterized relations between AVHRR channels and optical properties. (author) 28 refs.

  4. An approach to the optical characteristics calibration of the CCD camera system%CCD摄像系统光学特性的一种标定方法

    Institute of Scientific and Technical Information of China (English)

    吕伟涛; 陶善昌

    2001-01-01

    从定量化光学遥感测量的需求出发,给出了一种对CCD摄像系统的像素间隔、光电响应的非 线性和非均匀性等光学特性进行标定的方法,详细介绍了标定过程,并给出了部分测试结果。%In order to meet the demand of quantitative optical remote sense measurement, an approach to calibrate the pixels' interval, the photo-electric response non-l inearity and non-uniformity in CCD camera system is provided in this paper. Th e calibration procedure is introduced in details, and some experiment results are also given out.

  5. “嫦娥二号”卫星CCD立体相机的关键技术%Key Technologies of CE-2 CCD Stereo Camera

    Institute of Scientific and Technical Information of China (English)

    赵葆常; 唐茜; 薛彬

    2013-01-01

    文章介绍了中国两次绕月探测中 CCD 立体相机所采用的技术与创新,并与国际同类相机所获取的图像进行了比较;在此基础上详细介绍了“嫦娥二号”(CE-2)卫星CCD立体相机的综合创新集成技术--“单镜头两视角同轨立体成像、时间延迟积分图像传感器(TDICCD)推扫、速高比补偿”,并从工程目标与科学目标出发进行探测灵敏度及成像动态范围的需求分析;根据需求分析确定了总体技术方案,包括光、机、电的优化设计以及对月探测中首次采用TDICCD的技术困难与对策;特别讨论了速高比补偿的方案及实施途径,并进行了在轨试验验证。文章最后分别给出了虹湾地区成像分辨率为1.3m以及全月面分辨率为7m 的代表性图像,图像清晰、层次丰富,显示出中国在对月立体成像技术上取得了显著进步。%The paper describes the CCD-stereo camera’s novel techniques used in China’s two around-lunar reconnaissances and compares similar images of lunar terrain obtained by foreign cameras. The paper also details CCD stereo-camera’s overall scheme, i.e. synthetically integrating techniques of“same orbit stereo-imaging with two sight angles, TDICCD pushing scan and velocity/height ratio compensation”. It in-cludes the requirement analysis of the sensibility and imaging dynamical range for the sake of engineering and science goals. The overall scheme is established on the basis of the requirement analysis, including the opti-mizing designs with optics, machine and electronics and imaging capability analysis for this scheme. The scheme can fulfill the mission goals. The paper introduces the technical difficulties with time-delay-integration CCD for lunar high resolution stereo-imaging and the countermeasures employed, especially discusses the scheme and way for velocity/height ratio compensation and gives the executed validation on orbit. Finally, it shows

  6. Adaptive strategies of remote systems operators exposed to perturbed camera-viewing conditions

    Science.gov (United States)

    Stuart, Mark A.; Manahan, Meera K.; Bierschwale, John M.; Sampaio, Carlos E.; Legendre, A. J.

    1991-01-01

    This report describes a preliminary investigation of the use of perturbed visual feedback during the performance of simulated space-based remote manipulation tasks. The primary objective of this NASA evaluation was to determine to what extent operators exhibit adaptive strategies which allow them to perform these specific types of remote manipulation tasks more efficiently while exposed to perturbed visual feedback. A secondary objective of this evaluation was to establish a set of preliminary guidelines for enhancing remote manipulation performance and reducing the adverse effects. These objectives were accomplished by studying the remote manipulator performance of test subjects exposed to various perturbed camera-viewing conditions while performing a simulated space-based remote manipulation task. Statistical analysis of performance and subjective data revealed that remote manipulation performance was adversely affected by the use of perturbed visual feedback and performance tended to improve with successive trials in most perturbed viewing conditions.

  7. Development of low-noise high-speed analog ASIC for X-ray CCD cameras and wide-band X-ray imaging sensors

    Science.gov (United States)

    Nakajima, Hiroshi; Hirose, Shin-nosuke; Imatani, Ritsuko; Nagino, Ryo; Anabuki, Naohisa; Hayashida, Kiyoshi; Tsunemi, Hiroshi; Doty, John P.; Ikeda, Hirokazu; Kitamura, Hisashi; Uchihori, Yukio

    2016-09-01

    We report on the development and performance evaluation of the mixed-signal Application Specific Integrated Circuit (ASIC) developed for the signal processing of onboard X-ray CCD cameras and various types of X-ray imaging sensors in astrophysics. The quick and low-noise readout is essential for the pile-up free imaging spectroscopy with a future X-ray telescope. Our goal is the readout noise of 5e- r . m . s . at the pixel rate of 1 Mpix/s that is about 10 times faster than those of the currently working detectors. We successfully developed a low-noise ASIC as the front-end electronics of the Soft X-ray Imager onboard Hitomi that was launched on February 17, 2016. However, it has two analog-to-digital converters per chain due to the limited processing speed and hence we need to correct the difference of gain to obtain the X-ray spectra. Furthermore, its input equivalent noise performance is not satisfactory (> 100 μV) at the pixel rate higher than 500 kpix/s. Then we upgrade the design of the ASIC with the fourth-order ΔΣ modulators to enhance its inherent noise-shaping performance. Its performance is measured using pseudo CCD signals with variable processing speed. Although its input equivalent noise is comparable with the conventional one, the integrated non-linearity (0.1%) improves to about the half of that of the conventional one. The radiation tolerance is also measured with regard to the total ionizing dose effect and the single event latch-up using protons and Xenon, respectively. The former experiment shows that all of the performances does not change after imposing the dose corresponding to 590 years in a low earth orbit. We also put the upper limit on the frequency of the latch-up to be once per 48 years.

  8. Automatic sorting installation based on two CCD cameras for measuring gauge diameter and ellipticity of pulp extractors

    Science.gov (United States)

    Ovchinnikov, Dmitry L.; Akhtiamov, Rishad A.; Dorogov, Nikolai V.; Morozov, Oleg G.; Nureev, Ilnur I.; Yusupov, Alfred Y.

    2000-12-01

    The concrete problem, which decision is presented in given paper, consists in measuring of pulp extractor diameter apart 1 mm from its operating end and their automatic sorting. The range of measuring sizes is 180-260 micrometers , necessary measurement accuracy is 1 micrometers . The sorting is carried out on 8 subranges in 10 micrometers . The ellipticity of a pulp extractor is analyzed additionally and used as a qualitative index. The comparative analysis of different tools on metrology performances and cost problems of their embodying has allowed to select television system, as the class on the basis of which is necessary to build a required system. Problems decided at built-up of a system are: use of short focus lenses with major augmentation for shaping pulse duration solved for measuring to within 1 micrometers error; the account of lenses aberrations influence on a measuring error; use of cameras with a size of pixels in 0.7-1 micrometers ; definition of the line number, which corresponds to a gauge diameter of a pulp extractor; holding of a statistical average and extrapolation of data of measuring; the analysis of system variants with the purpose of its simplification and cost decreasing.

  9. HiPERCAM: A high-speed, quintuple-beam CCD camera for the study of rapid variability in the Universe

    CERN Document Server

    Dhillon, V S; Bezawada, N; Black, M; Dixon, S; Gamble, T; Henry, D; Kerry, P; Littlefair, S P; Lunney, D W; Morris, T; Osborn, J; Wilson, R W

    2016-01-01

    HiPERCAM is a high-speed camera for the study of rapid variability in the Universe. The project is funded by a 3.5MEuro European Research Council Advanced Grant. HiPERCAM builds on the success of our previous instrument, ULTRACAM, with very significant improvements in performance thanks to the use of the latest technologies. HiPERCAM will use 4 dichroic beamsplitters to image simultaneously in 5 optical channels covering the u'g'r'i'z' bands. Frame rates of over 1000 per second will be achievable using an ESO CCD controller (NGC), with every frame GPS timestamped. The detectors are custom-made, frame-transfer CCDs from e2v, with 4 low-noise (2.5e-) outputs, mounted in small thermoelectrically-cooled heads operated at 180 K, resulting in virtually no dark current. The two reddest CCDs will be deep-depletion devices with anti-etaloning, providing high quantum efficiencies across the red part of the spectrum with no fringing. The instrument will also incorporate scintillation noise correction via the conjugate-p...

  10. Method of CCD Camera Calibration Based On OpenCV%基于OpenCV的CCD摄像机标定方法

    Institute of Scientific and Technical Information of China (English)

    雷铭哲; 孙少杰; 陈晋良; 陶磊; 魏坤

    2014-01-01

    计算机视觉在工业,农业,军事,交通等领域都有着广泛应用。摄像机标定是视觉系统的重要环节,也是研究的关键领域。以摄像机标定技术为研究对象,选取针孔成像模型,简述了世界坐标系、摄像机坐标系和图像坐标系及其相互间的位置关系,对标定过程进行了深入研究。特别地,为提高标定精度,充分考虑了透镜径向和切向畸变影响及其求解方法,制作了棋盘格平面标定模板,基于开放计算机视觉函数库(OpenCV)实现了摄像机标定。该标定算法能够充分发挥OpenCV函数库功能,对于图像处理与计算机视觉方面的应用设计具有实用价值。实验结果表明该方法取得了较高精度,能够满足视觉检测或其他计算机视觉系统的应用需要。%Computer vision has been widely used in industry,agriculture,military,transportation area and so on. Camera calibration is very important and also the key research field of vision system. This paper mainly researches on the method of CCD camera calibration,the pin-hole model has been introduced and applied in process of calibration. Specially,in order to improve the accuracy,both radial and tangential lens distortion have been taken into account during the implement of calibration based on OpenCV. This kind of arithmetic has practical value on the application design of image processing and computer vision,and experiment results show good precision,which can meet the application need of visual inspection or other vision systems well.

  11. 基于OpenCV的CCD摄像机标定方法%Method of CCD Camera Calibration Based On OpenCV

    Institute of Scientific and Technical Information of China (English)

    雷铭哲; 孙少杰; 陈晋良; 陶磊; 魏坤

    2014-01-01

    计算机视觉在工业,农业,军事,交通等领域都有着广泛应用。摄像机标定是视觉系统的重要环节,也是研究的关键领域。以摄像机标定技术为研究对象,选取针孔成像模型,简述了世界坐标系、摄像机坐标系和图像坐标系及其相互间的位置关系,对标定过程进行了深入研究。特别地,为提高标定精度,充分考虑了透镜径向和切向畸变影响及其求解方法,制作了棋盘格平面标定模板,基于开放计算机视觉函数库(OpenCV)实现了摄像机标定。该标定算法能够充分发挥OpenCV函数库功能,对于图像处理与计算机视觉方面的应用设计具有实用价值。实验结果表明该方法取得了较高精度,能够满足视觉检测或其他计算机视觉系统的应用需要。%Computer vision has been widely used in industry,agriculture,military,transportation area and so on. Camera calibration is very important and also the key research field of vision system. This paper mainly researches on the method of CCD camera calibration,the pin-hole model has been introduced and applied in process of calibration. Specially,in order to improve the accuracy,both radial and tangential lens distortion have been taken into account during the implement of calibration based on OpenCV. This kind of arithmetic has practical value on the application design of image processing and computer vision,and experiment results show good precision,which can meet the application need of visual inspection or other vision systems well.

  12. Design Study of An Automtic Forest Fire Monitoring System based on CCD Cameras and ArcObjects%基于CCD摄像机和ArcObjects的森林火灾自动监测系统的设计研究

    Institute of Scientific and Technical Information of China (English)

    窦长娥; 费鲜芸

    2011-01-01

    通过安装在监控地点的CCD摄像机,借助卫星遥感技术、图像处理技术以及网络通讯设施,结合ArcObjects组件开发方式,在探讨森林火灾自动监测系统总体框架的基础上,对系统数据库和核心模块功能进行分析设计,建立基于CCD摄像机和ArcObjects的森林火灾自动监测系统,解决了传统的以人工实地为主的监测方式,采用CCD摄像机视频监控,结合图像处理技术和人工智能技术,提高了视频监控系统的能力.%The system database and core module function were designed based on the discussion of the general framework of the Automatic Forest Fire Monitoring System (AFFMS) by using CCD cameras which were installed in monitoring spots, ArcObjects technologies, satellite remote sensing technology, image processing technology and network communication function. The automated monitoring system for forest fire disaster based on CCD camera and ArcObjects were set up to solve the traditional artificial field observation method. Using CCD camera video monitoring, and combining with image process technology and artificial intelligence technology, the ability of video monitoring system was enhanced.

  13. 基于结构光和单CCD相机的物体表面三维测量%A New Method of Automatic Measurement for 3D Surface by Using Structured Light,Single CCD Camera

    Institute of Scientific and Technical Information of China (English)

    牟元英; 徐春斌

    2001-01-01

    Non-contact automatic measurement for 3D surface is one of central tasks of computer vision.Arounding this task ,a new method of automatic measurement for 3D surface by using structured light 、single CCD camera and double orientations techniques is proposed in this paper.The stereo coordinates of 3D surface can be obtained through a sequence monocular images without determining the relative position between camera (CCD) and structured light projector.%非接触式物体表面三维自动测量是计算机视觉领域的中心任务之一,围绕这个问题,提出了一种利用结构光,单CCD相机和双定向技术实现物体表面三维自动测量的新方法。采用该方法,无需测定相机和结构光光截面之间的相对位置,在单目序列影像上就可测量出物体表面的三维坐标。

  14. CCD sensors.

    OpenAIRE

    O. S. Neuimin; S. M. Dyachenko

    2010-01-01

    The principle of action, the basic parameters, the application CCD and achievements of the leading companies in their improved performance are considered. Methods of color image acquisition existing today are described. The table of parameters of modern image sensors which are used in modern technics are made.

  15. CCD sensors.

    Directory of Open Access Journals (Sweden)

    O. S. Neuimin

    2010-10-01

    Full Text Available The principle of action, the basic parameters, the application CCD and achievements of the leading companies in their improved performance are considered. Methods of color image acquisition existing today are described. The table of parameters of modern image sensors which are used in modern technics are made.

  16. Method of CCD test and screening for space camera with wide field of view%大视场空间相机CCD性能测试及筛选方法

    Institute of Scientific and Technical Information of China (English)

    李宪圣; 万志; 刘则洵; 李葆勇; 刘洪兴; 孙景旭; 任建伟

    2014-01-01

    CCD mosaic technology can effectively increase space camera′s field of view and image width. CCD′s performance difference will decrease space camera′s image quality. In order to screen the same high-performance CCDs for wide field of view space camera, a method of CCD test and screening was proposed. Firstly, the design of CCD′s imaging circuit and the test method of CCD′s spectral and radiant characteristics were introduced. Then, the screening process of the CCD was introduced, the first step was screening CCD on the basis of the geometry characteristics, signal-to-noise ratio, relative spectral responsivity, photo response non-uniformity, non-uniformity, non-linearity, dark current, and dynamic range, then the poor-performance CCD would be removed. Secondly, the CCD on basis of radiant response consistency was screened. And data analysis shows consistency screening method of saturation irradiance is better than consistency screening method of responsivity. Finally, the most consistent four CCDs was screened from ten CCDs by consistency screening method of saturation irradiance, whose saturation irradiances′ relative deviation was 0.23%. The screened four CCDs has been used in a wide field of view space camera, which received wonderful results.%空间相机使用CCD拼接技术组成长焦平面,可有效地增加空间相机的视场和幅宽。拼接CCD之间的性能差异会影响空间相机的成像质量,为了在大视场空间相机研制时挑选高性能且性能一致的CCD,提出了一种大视场空间相机CCD 性能测试与筛选方法。首先,介绍了CCD的成像电路设计、以及CCD光谱特性和辐射特性的测试方法。然后,介绍了CCD的筛选流程,第一步是从各CCD裸片的几何特性、信噪比、相对光谱响应、响应非均匀性、非线性、暗电流以及动态范围等角度进行筛选,将不满足指标的CCD剔除,第二步是依据辐射响应一致性筛选出满足要求

  17. Design of Hardware for CCD Video Surveillance Camera with External Synchronization Function%具有外同步功能的 CCD 视频监控摄像机硬件设计

    Institute of Scientific and Technical Information of China (English)

    国蓉; 焦旸; 高明; 杜玉军

    2014-01-01

    为了解决目标追踪中不同摄像机间识别目标的差异,在普通摄像机的基础上开发外同步功能。使用专用DSP微处理器CXD3172AR加EEPROM 的驱动方案,利用同步信号发生器和锁相环电路实现外同步功能。设计了信号处理电路,实现清晰的图像输出。实验结果表明,视频监控摄像机输出视频信号稳定,实现外同步功能,图像分辨率达752×528,输出帧率50帧/秒。%In order to solve the problem that the target identified by different cameras was discrepant during the process of tracking ,the external synchronization function is developed based on the common camera .Also ,a program is proposed ,taking CXD3172AR ,a microprocessor specially used in DSP and EEPROM as driver ,then using synchronous signal generator and phase locked loop circuit ,to achieve external synchronization .Meanwhile a signal processing circuit is designed to achieve the output of digital format . T he experimental results show that the video surveillance camera had the features of stable output signal ,external synchronization ,image resolution up to 752 × 528 and output frame rate up to 50 frames/s .

  18. A Simple Method Based on the Application of a CCD Camera as a Sensor to Detect Low Concentrations of Barium Sulfate in Suspension

    Directory of Open Access Journals (Sweden)

    Joao Francisco Cajaiba da Silva

    2011-01-01

    Full Text Available The development of a simple, rapid and low cost method based on video image analysis and aimed at the detection of low concentrations of precipitated barium sulfate is described. The proposed system is basically composed of a webcam with a CCD sensor and a conventional dichroic lamp. For this purpose, software for processing and analyzing the digital images based on the RGB (Red, Green and Blue color system was developed. The proposed method had shown very good repeatability and linearity and also presented higher sensitivity than the standard turbidimetric method. The developed method is presented as a simple alternative for future applications in the study of precipitations of inorganic salts and also for detecting the crystallization of organic compounds.

  19. 一种辨别暗袋曝光的方法%Method to Distinguish the Exposed Camera Bag

    Institute of Scientific and Technical Information of China (English)

    王勇; 吴凯; 陈海英; 肖俊

    2015-01-01

    在射线检测的暗袋表面加装少量磷光物质,则在暗袋曝光过程中,磷光物质吸收高能射线,其电子受到激发会跃迁至不稳定的高能态,在退激的过程中会持续释放可见光。通过在黑暗状态下观察磷光物质是否发光来判断该暗袋是否已使用过,从而避免对已使用过的暗袋进行重复曝光,节省了胶片和工时。%A small amount of phosphorescent powder was added to the camera bag′s surface,and then the phosphorescent powder began to absorb high-energy rays during the exposure process.In the exposure process, electrons would be excited to a higher unstable energy state,and should continue to release visible light in the subsequent de-excitation process.People could distinguish whether the camera bag was exposed or not by observing the visible light in dark state,thus double-exposure could be avoided effectively,saving both films and man-hours. This low-cost method is simple,convenient,and worth spreading.

  20. Soft X-ray transmission of optical blocking filters for the X-ray CCD cameras onboard Astro-E 2

    Energy Technology Data Exchange (ETDEWEB)

    Kitamoto, Shunji E-mail: kitamoto@rikkyo.ac.jp; Kohmura, Takayoshi; Yamamoto, Norimasa; Saito, Harue; Takano, Haruko; Suga, Kazuharu; Ozawa, Eiji; Suzuki, Kazuma; Kato, Risa; Tachibana, Yusuke; Tsuji, Yusuke; Koganei, Ken; Hayashida, Kiyoshi; Katayama, Haruyoshi; Enoguchi, Hideyuki; Nakashima, Yusuke; Shiroshouji, Takayuki

    2003-06-11

    We measured soft X-ray transmission of Optical Blocking Filters for Charge Coupled Device cameras, which will be launched as focal plane detectors of X-ray telescopes onboard the Japanese fifth X-ray astronomical satellite, Astro-E 2. The filters were made from polyimide coated with Al. The X-ray absorption fine structures at the K edges of C, N, O and Al were measured. The depth of the absorption edge of O was deep, compared to the other elements of polyimide. This is the evidence of the oxidation of Al.

  1. Linear CCD attitude measurement system based on the identification of the auxiliary array CCD

    Science.gov (United States)

    Hu, Yinghui; Yuan, Feng; Li, Kai; Wang, Yan

    2015-10-01

    Object to the high precision flying target attitude measurement issues of a large space and large field of view, comparing existing measurement methods, the idea is proposed of using two array CCD to assist in identifying the three linear CCD with multi-cooperative target attitude measurement system, and to address the existing nonlinear system errors and calibration parameters and more problems with nine linear CCD spectroscopic test system of too complicated constraints among camera position caused by excessive. The mathematical model of binocular vision and three linear CCD test system are established, co-spot composition triangle utilize three red LED position light, three points' coordinates are given in advance by Cooperate Measuring Machine, the red LED in the composition of the three sides of a triangle adds three blue LED light points as an auxiliary, so that array CCD is easier to identify three red LED light points, and linear CCD camera is installed of a red filter to filter out the blue LED light points while reducing stray light. Using array CCD to measure the spot, identifying and calculating the spatial coordinates solutions of red LED light points, while utilizing linear CCD to measure three red LED spot for solving linear CCD test system, which can be drawn from 27 solution. Measured with array CCD coordinates auxiliary linear CCD has achieved spot identification, and has solved the difficult problems of multi-objective linear CCD identification. Unique combination of linear CCD imaging features, linear CCD special cylindrical lens system is developed using telecentric optical design, the energy center of the spot position in the depth range of convergence in the direction is perpendicular to the optical axis of the small changes ensuring highprecision image quality, and the entire test system improves spatial object attitude measurement speed and precision.

  2. Intensified CCD Image Sensor①

    Institute of Scientific and Technical Information of China (English)

    LIUJikun; ZHAOBaoyun

    1997-01-01

    Work has been done with extending the useful imaging and detection rage of CCD.This was accomplished through direct optical coupling and bonding of image intensifiers to the CCD.It has been shown that the useful range of a CCD may be extended two orders of magnitude using these techniques in coupling a microchannel plate image intensifier to the CCD array.All of these works were done with presently available CCD made by China

  3. Testing fully depleted CCD

    Science.gov (United States)

    Casas, Ricard; Cardiel-Sas, Laia; Castander, Francisco J.; Jiménez, Jorge; de Vicente, Juan

    2014-08-01

    The focal plane of the PAU camera is composed of eighteen 2K x 4K CCDs. These devices, plus four spares, were provided by the Japanese company Hamamatsu Photonics K.K. with type no. S10892-04(X). These detectors are 200 μm thick fully depleted and back illuminated with an n-type silicon base. They have been built with a specific coating to be sensitive in the range from 300 to 1,100 nm. Their square pixel size is 15 μm. The read-out system consists of a Monsoon controller (NOAO) and the panVIEW software package. The deafualt CCD read-out speed is 133 kpixel/s. This is the value used in the calibration process. Before installing these devices in the camera focal plane, they were characterized using the facilities of the ICE (CSIC- IEEC) and IFAE in the UAB Campus in Bellaterra (Barcelona, Catalonia, Spain). The basic tests performed for all CCDs were to obtain the photon transfer curve (PTC), the charge transfer efficiency (CTE) using X-rays and the EPER method, linearity, read-out noise, dark current, persistence, cosmetics and quantum efficiency. The X-rays images were also used for the analysis of the charge diffusion for different substrate voltages (VSUB). Regarding the cosmetics, and in addition to white and dark pixels, some patterns were also found. The first one, which appears in all devices, is the presence of half circles in the external edges. The origin of this pattern can be related to the assembly process. A second one appears in the dark images, and shows bright arcs connecting corners along the vertical axis of the CCD. This feature appears in all CCDs exactly in the same position so our guess is that the pattern is due to electrical fields. Finally, and just in two devices, there is a spot with wavelength dependence whose origin could be the result of a defectous coating process.

  4. Measurement of chroma of LED displays with color CCD camera%用彩色CCD相机测量发光二极管显示屏的色度

    Institute of Scientific and Technical Information of China (English)

    赵梓权; 王瑞光; 郑喜凤; 汪洋

    2013-01-01

    A method by combination of a colorimeter and a color CCD to measure the brightness and chroma of color pixels of a Light Emitting Diode(LED) was proposed. Firstly, the color pixels of the LED were processed by the CCD camera and the brightness and chroma values of the LED pixels in RGB color space were calculated by image processing. Then, the multi-channel and adaptive matrix between RGB color space and CIE1931XYZ color space were established and the measured data of a few LED pixels were obtained by the colorimeter. With the RGB values and the measured data, the a-daptive matrix could be calculated. Finally, the tristimulus values of the LEDs were calculated with the adaptive matrix. Experimental results indicate that the color difference between calculated data and measured data is less than 1 in an appropriate size of adaptive matrix, which can obtain the brightness and chroma of color pixels of the LED rapidly and precisely, and can correct the brightness and chroma of the LED screen. The method can be used to measure hundreds of thousands of LEDs accu- rately in a short time.%提出了一种高精度色度计和彩色CCD相机相结合快速测量发光二极管(LED)显示像素的亮度和色度的方法.首先,用彩色CCD相机测量LED显示像素,通过图像处理提取每个LED显示像素点在RGB颜色空间中的亮度值和色度值.然后,建立RGB颜色空间和CIE 19 31XYZ颜色空间的多通道自适应矩阵,并使用色度计对部分LED显示像素点进行精确测量,基于精确测量值和对应的RGB值计算出自适应矩阵.最后,通过自适应矩阵计算出所有LED显示像素的亮度和色度值.实验结果表明:自适应矩阵大小合适的情况下,该方法计算出的数据与色度计测量数据之间的色差值△E<1,在人眼视觉中的颜色差异轻微,可快速、精确地采集LED显示像素的亮度和色度值,实现LED显示屏的高精度亮度、色度校正,从而大幅提高LED显示屏的显示效果.

  5. Large area CCD image sensors for space astronomy

    Science.gov (United States)

    Schwarzschild, M.

    1979-01-01

    The Defense Advanced Research Projects Agency (DARPA) has a substantial program to develop a 2200 x 2200 pixel CCD (Charge Coupled Device) mosaic array made up of 400 individual CCD's, 110 x 110 pixels square. This type of image sensor appeared to have application in space and ground-based astronomy. Under this grant a CCD television camera system was built which was capable of operating an array of 4 CCD's to explore the suitability of the CCD's to explore the suitability of the CCD for astronomical applications. Two individual packaged CCD's were received and evaluated. Evaluation of the basic characteristics of the best individual chips was encouraging, but the manufacturer found that their yield in manufacturing this design is two low to supply sufficient CDD's for the DARPA mosaic array. The potential utility of large mosaic arrays in astronomy is still substantial and continued monitoring of the manufacturers progress in the coming year is recommended.

  6. CCD characterization and measurements automation

    International Nuclear Information System (INIS)

    Modern mosaic cameras have grown both in size and in number of sensors. The required volume of sensor testing and characterization has grown accordingly. For camera projects as large as the LSST, test automation becomes a necessity. A CCD testing and characterization laboratory was built and is in operation for the LSST project. Characterization of LSST study contract sensors has been performed. The characterization process and its automation are discussed, and results are presented. Our system automatically acquires images, populates a database with metadata information, and runs express analysis. This approach is illustrated on 55Fe data analysis. 55Fe data are used to measure gain, charge transfer efficiency and charge diffusion. Examples of express analysis results are presented and discussed.

  7. The BCAM Camera

    CERN Document Server

    Hashemi, K S

    2000-01-01

    The BCAM, or Boston CCD Angle Monitor, is a camera looking at one or more light sources. We describe the application of the The BCAM, or Boston CCD Angle Monitor, is a camera looking at one or more light sources. We describe the application of the BCAM to the ATLAS forward muon detector alignment system. We show that the camera's performance is only weakly dependent upon the brightness, focus and diameter of the source image. Its resolution is dominated by turbulence along the external light path. The camera electronics is radiation-resistant. With a field of view of ± 10 mrad, it tracks the bearing of a light source 16 m away with better than 3 µrad accuracy, well within the ATLAS requirements.

  8. System for Digital 1D-Image Processing with 1024 Pixel CCD Sensor

    Directory of Open Access Journals (Sweden)

    J. Misun

    1993-11-01

    Full Text Available The conception of system for digital 1D-images processing with digital CCD camera is presented. The system is created from these three basic parts: the digital CCD camera with linear image sensor CCD L133C, 8-bit interface and a personal computer. The scanning digital CCD camera generated a video signals, which are processed in the analog signal processor. The output signal is continually converted to 8-bit data words in A/D converter. This data words maybe transfer over a bus driver to the operation memory of personal computer, by setting one of the three work regimes of digital CCD camera. Some application possibilities and basic technical parameters of this system are given.

  9. 基于CCD拼接的航空相机小波自动调焦方法研究%An Automatic Wavelet Focusing Method of the Aerial Camera Based on CCD Mosaicing

    Institute of Scientific and Technical Information of China (English)

    李珊珊; 徐丰; 刘杨; 邢变丽

    2012-01-01

    为精确地进行航空相机调焦,获取高清晰度的航空影像,结合CCD拼接的特点,提出一种新的航空相机调焦方法,便于航空成像设备进行自动调焦.考虑人类视觉系统的特点设置权值,利用图像的小波分解系数构造清晰度评价函数;分析小波基函数的性质,对不同频率成分的影像进行清晰度评价,从而使评价函数对图像的变化具有适应性,通过比较得出了利用symlet2小波进行3层分解获得的评价函数的效果最佳.为了提高清晰度评价函数的灵敏度,选取了细节丰富的区域作为评价区域,详细地阐述了航空相机利用CCD拼接结构的特点进行调焦的算法实现过程.试验证明,该方法获得的评价函数比传统的小波方法灵敏度高,可以满足航空相机的需要,大大提高了地物目标的识别和提取的精度.%In order to eraluate the image obtained by the aerial camera more clarely, a focusing method which could auto-focus was proposed to consider the characteristic of the mosaicing structure. The evaluation function has taken the characteristic of the human vision system (HVS) into account to set the weights, and is constructed by the wavelet coefficients of the image. For the sake of making the function suit to different images, the properties of the wavelet basis were analyzed. By comparing the evaluating effect of different images, the wavelet basis with the best effect was symlet2 and the level of decomposing was three. Meanwhile, the area with high frequency component was chosen as the evaluation area in order to improve the sensitivity of the evaluation function. In this paper, the flow chart of the focusing based on this method was described particularly. The simulation result showed that the evaluation function obtained by this method is more sensitive and a-daptive than the traditional wavelet methods. It could acquire high image quality, and meet the application in focusing system of the aerial

  10. Thermal management for CCD peformance of one space telescope

    Science.gov (United States)

    Yang, Wengang; Wang, Yinghao; Feng, Liangjie; Wang, Chenjie; Ren, Guorui; Wang, Wei; Li, Chuang; Gao, Wei; Fan, Xuewu

    2012-10-01

    A space telescope containing two CCD cameras is being built for scientific observation. The CCD detectors need to operate at a temperature below -65°C in order to avoid unacceptable dark current. This cooling is achieved through detailed thermal design which minimizes the parasitic load to 2K×4K array with 13.5 micron pixels and cools this detector with a combination of thermo electric cooler(TEC). This paper will describe detailed thermal design necessary to maintain the CCD at its cold operating temperature while providing the means to reject the heat generated by the TECs. It will focus on optimized techniques developed to manage parasitic loads including material selection, surface finishes and thermal insulation. The paper will also address analytical techniques developed to characterize TEC performance. Finally, analysis results have been shown the temperature of key parts.

  11. Design and Characterization of the CCD Detector Assemblies for ICON FUV

    Science.gov (United States)

    Champagne, J.; Syrstad, E. A.; Siegmund, O.; Darling, N.; Jelinsky, S. R.; Curtis, T.

    2015-12-01

    The Far Ultraviolet Imaging Spectrograph (FUV) on the upcoming Ionospheric Connection Explorer (ICON) mission uses dual image-intensified CCD camera systems, capable of detecting individual UV photons from both spectrometer channels (135.6 and 155 nm). Incident photons are converted to visible light using a sealed tube UV converter. The converter output is coupled to the CCD active area using a bonded fiber optic taper. The CCD (Teledyne DALSA FTT1010M) is a 1024x1024 frame transfer architecture. The camera readout electronics provide video imagery to the spacecraft over a 21 bit serialized LVDS interface, nominally at 10 frames per second and in 512x512 format (2x2 pixel binning). The CCD and primary electronics assembly reside in separate thermal zones, to minimize dark current without active cooling.Engineering and flight camera systems have been assembled, integrated, and tested under both ambient pressure and thermal vacuum environments. The CCD cameras have been fully characterized with both visible light (prior to integration with the UV converter) and UV photons (following system integration). Measured parameters include camera dark current, dark signal non-uniformity, read noise, linearity, gain, pulse height distribution, dynamic range, charge transfer efficiency, resolution, relative efficiency, quantum efficiency, and full well capacity. UV characterization of the camera systems over a range of microchannel plate (MCP) voltages during thermal vacuum testing demonstrates that camera performance will meet the critical on-orbit FUV dynamic range requirements. Flight camera integration with the FUV instrument and sensor calibration is planned for Fall 2015. Camera design and full performance data for the engineering and flight model cameras will be presented.

  12. CCD Readout Electronics for the Subaru Prime Focus Spectrograph

    OpenAIRE

    Hope, Stephen C.; Gunn, James E.; Loomis, Craig P.; Fitzgerald, Roger E.; Peacock, Grant O.

    2014-01-01

    We present details of the design for the CCD readout electronics for the Subaru Telescope Prime Focus Spectrograph (PFS). The spectrograph is comprised of four identical spectrograph modules, each collecting roughly 600 spectra. The spectrograph modules provide simultaneous wavelength coverage over the entire band from 380 nm to 1260 nm through the use of three separate optical channels: blue, red, and near infrared (NIR). A camera in each channel images the multi-object spectra onto a 4k x 4...

  13. CCD image enhancement techniques for high-noise devices

    Science.gov (United States)

    Wrochna, Grzegorz

    2003-10-01

    Rapid progress in scientific research enlarges the gap between amateurs and professional scientists. Modern astronomy is based on technologically advanced CCD cameras and large, computer driven telescopes. An investment of about $10,000 is needed for an amateur to join the club of digital observers. In this paper we describe an attempt to break this barrier by developing entry-level systems in the range of $200-$2000.

  14. The Dark Energy Camera

    Energy Technology Data Exchange (ETDEWEB)

    Flaugher, B. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States). et al.

    2015-04-11

    The Dark Energy Camera is a new imager with a 2.2-degree diameter field of view mounted at the prime focus of the Victor M. Blanco 4-meter telescope on Cerro Tololo near La Serena, Chile. The camera was designed and constructed by the Dark Energy Survey Collaboration, and meets or exceeds the stringent requirements designed for the wide-field and supernova surveys for which the collaboration uses it. The camera consists of a five element optical corrector, seven filters, a shutter with a 60 cm aperture, and a CCD focal plane of 250-μm thick fully depleted CCDs cooled inside a vacuum Dewar. The 570 Mpixel focal plane comprises 62 2k x 4k CCDs for imaging and 12 2k x 2k CCDs for guiding and focus. The CCDs have 15μm x 15μm pixels with a plate scale of 0.263" per pixel. A hexapod system provides state-of-the-art focus and alignment capability. The camera is read out in 20 seconds with 6-9 electrons readout noise. This paper provides a technical description of the camera's engineering, construction, installation, and current status.

  15. The Dark Energy Camera

    CERN Document Server

    Flaugher, B; Honscheid, K; Abbott, T M C; Alvarez, O; Angstadt, R; Annis, J T; Antonik, M; Ballester, O; Beaufore, L; Bernstein, G M; Bernstein, R A; Bigelow, B; Bonati, M; Boprie, D; Brooks, D; Buckley-Geer, E J; Campa, J; Cardiel-Sas, L; Castander, F J; Castilla, J; Cease, H; Cela-Ruiz, J M; Chappa, S; Chi, E; Cooper, C; da Costa, L N; Dede, E; Derylo, G; DePoy, D L; de Vicente, J; Doel, P; Drlica-Wagner, A; Eiting, J; Elliott, A E; Emes, J; Estrada, J; Neto, A Fausti; Finley, D A; Flores, R; Frieman, J; Gerdes, D; Gladders, M D; Gregory, B; Gutierrez, G R; Hao, J; Holland, S E; Holm, S; Huffman, D; Jackson, C; James, D J; Jonas, M; Karcher, A; Karliner, I; Kent, S; Kessler, R; Kozlovsky, M; Kron, R G; Kubik, D; Kuehn, K; Kuhlmann, S; Kuk, K; Lahav, O; Lathrop, A; Lee, J; Levi, M E; Lewis, P; Li, T S; Mandrichenko, I; Marshall, J L; Martinez, G; Merritt, K W; Miquel, R; Munoz, F; Neilsen, E H; Nichol, R C; Nord, B; Ogando, R; Olsen, J; Palio, N; Patton, K; Peoples, J; Plazas, A A; Rauch, J; Reil, K; Rheault, J -P; Roe, N A; Rogers, H; Roodman, A; Sanchez, E; Scarpine, V; Schindler, R H; Schmidt, R; Schmitt, R; Schubnell, M; Schultz, K; Schurter, P; Scott, L; Serrano, S; Shaw, T M; Smith, R C; Soares-Santos, M; Stefanik, A; Stuermer, W; Suchyta, E; Sypniewski, A; Tarle, G; Thaler, J; Tighe, R; Tran, C; Tucker, D; Walker, A R; Wang, G; Watson, M; Weaverdyck, C; Wester, W; Woods, R; Yanny, B

    2015-01-01

    The Dark Energy Camera is a new imager with a 2.2-degree diameter field of view mounted at the prime focus of the Victor M. Blanco 4-meter telescope on Cerro Tololo near La Serena, Chile. The camera was designed and constructed by the Dark Energy Survey Collaboration, and meets or exceeds the stringent requirements designed for the wide-field and supernova surveys for which the collaboration uses it. The camera consists of a five element optical corrector, seven filters, a shutter with a 60 cm aperture, and a CCD focal plane of 250 micron thick fully-depleted CCDs cooled inside a vacuum Dewar. The 570 Mpixel focal plane comprises 62 2kx4k CCDs for imaging and 12 2kx2k CCDs for guiding and focus. The CCDs have 15 microns x15 microns pixels with a plate scale of 0.263 arc sec per pixel. A hexapod system provides state-of-the-art focus and alignment capability. The camera is read out in 20 seconds with 6-9 electrons readout noise. This paper provides a technical description of the camera's engineering, construct...

  16. The Dark Energy Camera

    Science.gov (United States)

    Flaugher, B.; Diehl, H. T.; Honscheid, K.; Abbott, T. M. C.; Alvarez, O.; Angstadt, R.; Annis, J. T.; Antonik, M.; Ballester, O.; Beaufore, L.; Bernstein, G. M.; Bernstein, R. A.; Bigelow, B.; Bonati, M.; Boprie, D.; Brooks, D.; Buckley-Geer, E. J.; Campa, J.; Cardiel-Sas, L.; Castander, F. J.; Castilla, J.; Cease, H.; Cela-Ruiz, J. M.; Chappa, S.; Chi, E.; Cooper, C.; da Costa, L. N.; Dede, E.; Derylo, G.; DePoy, D. L.; de Vicente, J.; Doel, P.; Drlica-Wagner, A.; Eiting, J.; Elliott, A. E.; Emes, J.; Estrada, J.; Fausti Neto, A.; Finley, D. A.; Flores, R.; Frieman, J.; Gerdes, D.; Gladders, M. D.; Gregory, B.; Gutierrez, G. R.; Hao, J.; Holland, S. E.; Holm, S.; Huffman, D.; Jackson, C.; James, D. J.; Jonas, M.; Karcher, A.; Karliner, I.; Kent, S.; Kessler, R.; Kozlovsky, M.; Kron, R. G.; Kubik, D.; Kuehn, K.; Kuhlmann, S.; Kuk, K.; Lahav, O.; Lathrop, A.; Lee, J.; Levi, M. E.; Lewis, P.; Li, T. S.; Mandrichenko, I.; Marshall, J. L.; Martinez, G.; Merritt, K. W.; Miquel, R.; Muñoz, F.; Neilsen, E. H.; Nichol, R. C.; Nord, B.; Ogando, R.; Olsen, J.; Palaio, N.; Patton, K.; Peoples, J.; Plazas, A. A.; Rauch, J.; Reil, K.; Rheault, J.-P.; Roe, N. A.; Rogers, H.; Roodman, A.; Sanchez, E.; Scarpine, V.; Schindler, R. H.; Schmidt, R.; Schmitt, R.; Schubnell, M.; Schultz, K.; Schurter, P.; Scott, L.; Serrano, S.; Shaw, T. M.; Smith, R. C.; Soares-Santos, M.; Stefanik, A.; Stuermer, W.; Suchyta, E.; Sypniewski, A.; Tarle, G.; Thaler, J.; Tighe, R.; Tran, C.; Tucker, D.; Walker, A. R.; Wang, G.; Watson, M.; Weaverdyck, C.; Wester, W.; Woods, R.; Yanny, B.; DES Collaboration

    2015-11-01

    The Dark Energy Camera is a new imager with a 2.°2 diameter field of view mounted at the prime focus of the Victor M. Blanco 4 m telescope on Cerro Tololo near La Serena, Chile. The camera was designed and constructed by the Dark Energy Survey Collaboration and meets or exceeds the stringent requirements designed for the wide-field and supernova surveys for which the collaboration uses it. The camera consists of a five-element optical corrector, seven filters, a shutter with a 60 cm aperture, and a charge-coupled device (CCD) focal plane of 250 μm thick fully depleted CCDs cooled inside a vacuum Dewar. The 570 megapixel focal plane comprises 62 2k × 4k CCDs for imaging and 12 2k × 2k CCDs for guiding and focus. The CCDs have 15 μm × 15 μm pixels with a plate scale of 0.″263 pixel-1. A hexapod system provides state-of-the-art focus and alignment capability. The camera is read out in 20 s with 6-9 electron readout noise. This paper provides a technical description of the camera's engineering, construction, installation, and current status.

  17. CCD Astrophotography High-Quality Imaging from the Suburbs

    CERN Document Server

    Stuart, Adam

    2006-01-01

    This is a reference book for amateur astronomers who have become interested in CCD imaging. Those glorious astronomical images found in astronomy magazines might seem out of reach to newcomers to CCD imaging, but this is not the case. Great pictures are attainable with modest equipment. Adam Stuart’s many beautiful images, reproduced in this book, attest to the quality of – initially – a beginner’s efforts. Chilled-chip astronomical CCD-cameras and software are also wonderful tools for cutting through seemingly impenetrable light-pollution. CCD Astrophotography from the Suburbs describes one man’s successful approach to the problem of getting high-quality astronomical images under some of the most light-polluted conditions. Here is a complete and thoroughly tested program that will help every CCD-beginner to work towards digital imaging of the highest quality. It is equally useful to astronomers who have perfect observing conditions, as to those who have to observe from light-polluted city skies.

  18. CCD guidance system for the William Herschel Telescope

    Science.gov (United States)

    Thorne, D. J.; Waltham, N. R.; Newton, G. M.; van Breda, I. G.; Fisher, M.

    1990-07-01

    The CCD autoguider detector system for the William Herschel Telescope (WHT) comprises a Peltier cooled, slow-scan CCD camera supported by an MC68020-based VME computer for image processing. The detector is a fluorescent dye coated EEV P8603 CCD chip operated in frame transfer mode. The CCD controller enables a full image to be read out during acquisition, but with windowed readout during guiding so as to permit an increased frame rate. The windowing is controlled by the VME computer, which is also used to calculate the centroid of the guide star and provides a local user interface, displaying images and guider status information. Special attention has been paid to the CCD drive clocks and bias voltages, enabling a very low dark current to be achieved (2 electrons per pixel per second at -35 C) without the need for extreme cooling. Guiding to magnitude 19 on the WHT has been demonstrated during dark time, with an integration time of one second.

  19. Parallel optical coherence tomography using a CCD camera

    Institute of Scientific and Technical Information of China (English)

    Junle Qu(屈军乐); Ravi S.Jonnal; Donald T. Miller

    2004-01-01

    Parallel optical coherence tomography is demonstrated using a 12-bit scientific-grade charge-coupled device array.A superluminescent diode in combination with a free-space Michelson interferometer was employed to achieve 10-μm axial resolution and 1.1-μm transverse resolution on a 902×575 μm2 field of view.We imaged a test mirror and bovine retinal tissue using a four-step phase shift method.

  20. Optimization of precision localization microscopy using CMOS camera technology

    Science.gov (United States)

    Fullerton, Stephanie; Bennett, Keith; Toda, Eiji; Takahashi, Teruo

    2012-02-01

    Light microscopy imaging is being transformed by the application of computational methods that permit the detection of spatial features below the optical diffraction limit. Successful localization microscopy (STORM, dSTORM, PALM, PhILM, etc.) relies on the precise position detection of fluorescence emitted by single molecules using highly sensitive cameras with rapid acquisition speeds. Electron multiplying CCD (EM-CCD) cameras are the current standard detector for these applications. Here, we challenge the notion that EM-CCD cameras are the best choice for precision localization microscopy and demonstrate, through simulated and experimental data, that certain CMOS detector technology achieves better localization precision of single molecule fluorophores. It is well-established that localization precision is limited by system noise. Our findings show that the two overlooked noise sources relevant for precision localization microscopy are the shot noise of the background light in the sample and the excess noise from electron multiplication in EM-CCD cameras. At low light conditions (CCD cameras are the preferred detector. However, in practical applications, optical background noise is significant, creating conditions where CMOS performs better than EM-CCD. Furthermore, the excess noise of EM-CCD is equivalent to reducing the information content of each photon detected which, in localization microscopy, reduces the precision of the localization. Thus, new CMOS technology with 100fps, super resolution precision localization microscopy.

  1. PAU camera: detectors characterization

    Science.gov (United States)

    Casas, Ricard; Ballester, Otger; Cardiel-Sas, Laia; Castilla, Javier; Jiménez, Jorge; Maiorino, Marino; Pío, Cristóbal; Sevilla, Ignacio; de Vicente, Juan

    2012-07-01

    The PAU Camera (PAUCam) [1,2] is a wide field camera that will be mounted at the corrected prime focus of the William Herschel Telescope (Observatorio del Roque de los Muchachos, Canary Islands, Spain) in the next months. The focal plane of PAUCam is composed by a mosaic of 18 CCD detectors of 2,048 x 4,176 pixels each one with a pixel size of 15 microns, manufactured by Hamamatsu Photonics K. K. This mosaic covers a field of view (FoV) of 60 arcmin (minutes of arc), 40 of them are unvignetted. The behaviour of these 18 devices, plus four spares, and their electronic response should be characterized and optimized for the use in PAUCam. This job is being carried out in the laboratories of the ICE/IFAE and the CIEMAT. The electronic optimization of the CCD detectors is being carried out by means of an OG (Output Gate) scan and maximizing it CTE (Charge Transfer Efficiency) while the read-out noise is minimized. The device characterization itself is obtained with different tests. The photon transfer curve (PTC) that allows to obtain the electronic gain, the linearity vs. light stimulus, the full-well capacity and the cosmetic defects. The read-out noise, the dark current, the stability vs. temperature and the light remanence.

  2. Deployable Wireless Camera Penetrators

    Science.gov (United States)

    Badescu, Mircea; Jones, Jack; Sherrit, Stewart; Wu, Jiunn Jeng

    2008-01-01

    A lightweight, low-power camera dart has been designed and tested for context imaging of sampling sites and ground surveys from an aerobot or an orbiting spacecraft in a microgravity environment. The camera penetrators also can be used to image any line-of-sight surface, such as cliff walls, that is difficult to access. Tethered cameras to inspect the surfaces of planetary bodies use both power and signal transmission lines to operate. A tether adds the possibility of inadvertently anchoring the aerobot, and requires some form of station-keeping capability of the aerobot if extended examination time is required. The new camera penetrators are deployed without a tether, weigh less than 30 grams, and are disposable. They are designed to drop from any altitude with the boost in transmitting power currently demonstrated at approximately 100-m line-of-sight. The penetrators also can be deployed to monitor lander or rover operations from a distance, and can be used for surface surveys or for context information gathering from a touch-and-go sampling site. Thanks to wireless operation, the complexity of the sampling or survey mechanisms may be reduced. The penetrators may be battery powered for short-duration missions, or have solar panels for longer or intermittent duration missions. The imaging device is embedded in the penetrator, which is dropped or projected at the surface of a study site at 90 to the surface. Mirrors can be used in the design to image the ground or the horizon. Some of the camera features were tested using commercial "nanny" or "spy" camera components with the charge-coupled device (CCD) looking at a direction parallel to the ground. Figure 1 shows components of one camera that weighs less than 8 g and occupies a volume of 11 cm3. This camera could transmit a standard television signal, including sound, up to 100 m. Figure 2 shows the CAD models of a version of the penetrator. A low-volume array of such penetrator cameras could be deployed from an

  3. Influences of CCD nonlinear response on measurement of propagation factor M2 of a laser beam

    International Nuclear Information System (INIS)

    In this paper, we analyze the influence of the nonlinear optoelectronic response on the measurement of the beam propagation factor M2 at different laser wavelengths. According to our theoretical investigation, the size of a laser beam with a standard Gaussian distribution will be estimated as larger than the real value when the response of a commercial non-calibrated CCD camera has a nonlinear relation to the recorded signal intensity. It has been demonstrated that the measurement accuracy in M2 becomes considerably worse by using such a CCD camera. The conclusion is thought to be useful for evaluation of the laser features in both research activities and industrial applications

  4. CCD readout electronics for the Subaru Prime Focus Spectrograph

    Science.gov (United States)

    Hope, Stephen C.; Gunn, James E.; Loomis, Craig P.; Fitzgerald, Roger E.; Peacock, Grant O.

    2014-07-01

    The following paper details the design for the CCD readout electronics for the Subaru Telescope Prime Focus Spectrograph (PFS). PFS is designed to gather spectra from 2394 objects simultaneously, covering wavelengths that extend from 380 nm to 1260 nm. The spectrograph is comprised of four identical spectrograph modules, each collecting roughly 600 spectra. The spectrograph modules provide simultaneous wavelength coverage over the entire band through the use of three separate optical channels: blue, red, and near infrared (NIR). A camera in each channel images the multi-object spectra onto a 4k × 4k, 15 μm pixel, detector format. The two visible cameras use a pair of Hamamatsu 2k × 4k CCDs with readout provided by custom electronics, while the NIR camera uses a single Teledyne HgCdTe 4k × 4k detector and Teledyne's ASIC Sidecar to read the device. The CCD readout system is a custom design comprised of three electrical subsystems - the Back End Electronics (BEE), the Front End Electronics (FEE), and a Pre-amplifier. The BEE is an off-the-shelf PC104 computer, with an auxiliary Xilinx FPGA module. The computer serves as the main interface to the Subaru messaging hub and controls other peripheral devices associated with the camera, while the FPGA is used to generate the necessary clocks and transfer image data from the CCDs. The FEE board sets clock biases, substrate bias, and CDS offsets. It also monitors bias voltages, offset voltages, power rail voltage, substrate voltage and CCD temperature. The board translates LVDS clock signals to biased clocks and returns digitized analog data via LVDS. Monitoring and control messages are sent from the BEE to the FEE using a standard serial interface. The Pre-amplifier board resides behind the detectors and acts as an interface to the two Hamamatsu CCDs. The Pre-amplifier passes clocks and biases to the CCDs, and analog CCD data is buffered and amplified prior to being returned to the FEE. In this paper we describe the

  5. Adaptive compressive sensing camera

    Science.gov (United States)

    Hsu, Charles; Hsu, Ming K.; Cha, Jae; Iwamura, Tomo; Landa, Joseph; Nguyen, Charles; Szu, Harold

    2013-05-01

    We have embedded Adaptive Compressive Sensing (ACS) algorithm on Charge-Coupled-Device (CCD) camera based on the simplest concept that each pixel is a charge bucket, and the charges comes from Einstein photoelectric conversion effect. Applying the manufactory design principle, we only allow altering each working component at a minimum one step. We then simulated what would be such a camera can do for real world persistent surveillance taking into account of diurnal, all weather, and seasonal variations. The data storage has saved immensely, and the order of magnitude of saving is inversely proportional to target angular speed. We did design two new components of CCD camera. Due to the matured CMOS (Complementary metal-oxide-semiconductor) technology, the on-chip Sample and Hold (SAH) circuitry can be designed for a dual Photon Detector (PD) analog circuitry for changedetection that predicts skipping or going forward at a sufficient sampling frame rate. For an admitted frame, there is a purely random sparse matrix [Φ] which is implemented at each bucket pixel level the charge transport bias voltage toward its neighborhood buckets or not, and if not, it goes to the ground drainage. Since the snapshot image is not a video, we could not apply the usual MPEG video compression and Hoffman entropy codec as well as powerful WaveNet Wrapper on sensor level. We shall compare (i) Pre-Processing FFT and a threshold of significant Fourier mode components and inverse FFT to check PSNR; (ii) Post-Processing image recovery will be selectively done by CDT&D adaptive version of linear programming at L1 minimization and L2 similarity. For (ii) we need to determine in new frames selection by SAH circuitry (i) the degree of information (d.o.i) K(t) dictates the purely random linear sparse combination of measurement data a la [Φ]M,N M(t) = K(t) Log N(t).

  6. CCD Photometry of bright stars using objective wire mesh

    International Nuclear Information System (INIS)

    Obtaining accurate photometry of bright stars from the ground remains problematic due to the danger of overexposing the target and/or the lack of suitable nearby comparison stars. The century-old method of using objective wire mesh to produce multiple stellar images seems promising for the precise CCD photometry of such stars. Furthermore, our tests on β Cep and its comparison star, differing by 5 mag, are very encouraging. Using a CCD camera and a 20 cm telescope with the objective covered by a plastic wire mesh, in poor weather conditions, we obtained differential photometry with a precision of 4.5 mmag per two minute exposure. Our technique is flexible and may be tuned to cover a range as big as 6-8 mag. We discuss the possibility of installing a wire mesh directly in the filter wheel.

  7. CCD Readout Electronics for the Subaru Prime Focus Spectrograph

    CERN Document Server

    Hope, Stephen C; Loomis, Craig P; Fitzgerald, Roger E; Peacock, Grant O

    2014-01-01

    We present details of the design for the CCD readout electronics for the Subaru Telescope Prime Focus Spectrograph (PFS). The spectrograph is comprised of four identical spectrograph modules, each collecting roughly 600 spectra. The spectrograph modules provide simultaneous wavelength coverage over the entire band from 380 nm to 1260 nm through the use of three separate optical channels: blue, red, and near infrared (NIR). A camera in each channel images the multi-object spectra onto a 4k x 4k, 15 um pixel, detector format. The two visible cameras use a pair of Hamamatsu 2k x 4k CCDs with readout provided by custom electronics, while the NIR camera uses a single Teledyne HgCdTe 4k x 4k detector and ASIC Sidecar to read the device. The CCD readout system is a custom design comprised of three electrical subsystems: the Back End Electronics (BEE), the Front End Electronics (FEE), and a Pre-amplifier. The BEE is an off-the-shelf PC104 computer, with an auxiliary Xilinx FPGA module. The computer serves as the main...

  8. Use of a charge-coupled device camera for broadband coherent anti-Stokes Raman scattering measurements.

    Science.gov (United States)

    Rakestraw, D J; Lucht, R P; Dreier, T

    1989-10-01

    The use of an unintensified charge-coupled device (CCD) camera for the acquisition of broadband CARS signals is demonstrated. The CCD camera offers significant advantages compared to intensified, linear photodiode array (PDA) detectors that are generally used for broadband CARS measurements. These advantages include higher spectral resolution and improved instrument function, larger dynamic range, and a 2-D format. PMID:20555836

  9. BLAST Autonomous Daytime Star Cameras

    CERN Document Server

    Rex, M; Devlin, M J; Gundersen, J; Klein, J; Pascale, E; Wiebe, D; Rex, Marie; Chapin, Edward; Devlin, Mark J.; Gundersen, Joshua; Klein, Jeff; Pascale, Enzo; Wiebe, Donald

    2006-01-01

    We have developed two redundant daytime star cameras to provide the fine pointing solution for the balloon-borne submillimeter telescope, BLAST. The cameras are capable of providing a reconstructed pointing solution with an absolute accuracy < 5 arcseconds. They are sensitive to stars down to magnitudes ~ 9 in daytime float conditions. Each camera combines a 1 megapixel CCD with a 200 mm f/2 lens to image a 2 degree x 2.5 degree field of the sky. The instruments are autonomous. An internal computer controls the temperature, adjusts the focus, and determines a real-time pointing solution at 1 Hz. The mechanical details and flight performance of these instruments are presented.

  10. Gamma camera

    International Nuclear Information System (INIS)

    The design of a collimation system for a gamma camera for use in nuclear medicine is described. When used with a 2-dimensional position sensitive radiation detector, the novel system can produce superior images than conventional cameras. The optimal thickness and positions of the collimators are derived mathematically. (U.K.)

  11. Digital X-ray detector based on a CCD matrix

    International Nuclear Information System (INIS)

    The application of charge-coupled devices (CCD) as position-sensitive detectors for X-ray radiation is discussed. The experimental scheme contains a videotransmission camera to detect pulsed X-ray radiation and Vektor analog-to-digital converters and computer interface. It is shown that the sensitivity range of a K1200TsM1 matrix to bremsstrahlung with an average energy of 75 keV is 2.7·10-8-0.8·10-6 J/cm2. The spatial resolution of the resultant X-ray image is discussed. 5 refs., 5 figs

  12. Subpixel translation of MEMS measured by discrete fourier transform analysis of CCD images

    NARCIS (Netherlands)

    Yamahata, C.; Sarajlic, E.; Stranczl, M.; Krijnen, G.J.M.; Gijs, M.A.M.

    2011-01-01

    We present a straightforward method for measuring in-plane linear displacements of microelectromechanical systems (MEMS) with subnanometer resolution. The technique is based on Fourier transform analysis of a video recorded with a Charge-Coupled Device (CCD) camera attached to an optical microscope

  13. Medición de coeficientes de extinción en CASLEO y características del CCD ROPER-2048B del telescopio JS

    Science.gov (United States)

    Fernández-Lajús, E.; Gamen, R.; Sánchez, M.; Scalia, M. C.; Baume, G. L.

    2016-08-01

    From observations made with the ``Jorge Sahade'' telescope of the Complejo Astronomico El Leoncito, the UBVRI-band extinction coeficients were measured, and some parameters and characteristics of the direct-image CCD camera ROPER 2048B were determined.

  14. Illumination box and camera system

    Science.gov (United States)

    Haas, Jeffrey S.; Kelly, Fredrick R.; Bushman, John F.; Wiefel, Michael H.; Jensen, Wayne A.; Klunder, Gregory L.

    2002-01-01

    A hand portable, field-deployable thin-layer chromatography (TLC) unit and a hand portable, battery-operated unit for development, illumination, and data acquisition of the TLC plates contain many miniaturized features that permit a large number of samples to be processed efficiently. The TLC unit includes a solvent tank, a holder for TLC plates, and a variety of tool chambers for storing TLC plates, solvent, and pipettes. After processing in the TLC unit, a TLC plate is positioned in a collapsible illumination box, where the box and a CCD camera are optically aligned for optimal pixel resolution of the CCD images of the TLC plate. The TLC system includes an improved development chamber for chemical development of TLC plates that prevents solvent overflow.

  15. Method to implement the CCD timing generator based on FPGA

    Science.gov (United States)

    Li, Binhua; Song, Qian; He, Chun; Jin, Jianhui; He, Lin

    2010-07-01

    With the advance of the PFPA technology, the design methodology of digital systems is changing. In recent years we develop a method to implement the CCD timing generator based on FPGA and VHDL. This paper presents the principles and implementation skills of the method. Taking a developed camera as an example, we introduce the structure, input and output clocks/signals of a timing generator implemented in the camera. The generator is composed of a top module and a bottom module. The bottom one is made up of 4 sub-modules which correspond to 4 different operation modes. The modules are implemented by 5 VHDL programs. Frame charts of the architecture of these programs are shown in the paper. We also describe implementation steps of the timing generator in Quartus II, and the interconnections between the generator and a Nios soft core processor which is the controller of this generator. Some test results are presented in the end.

  16. A fast double shutter system for CCD image sensors

    International Nuclear Information System (INIS)

    A new fast shutter system for CCD sensor-based cameras is presented. This system is capable of providing for the first time short exposure times for two consecutive frames recorded in fast succession with high spatial resolutions. In addition, a third frame can be recorded with a long exposure time, this then corresponding to the well-known ‘double shutter’. Measurement techniques such as particle image velocimetry (PIV) will benefit from the new fast shutter when being used in bright environments. Using the optional third frame, advanced evaluation schemes can be implemented to measure acceleration, increase the dynamic range of the velocity measurements or reduce the number of false matches (ghost particles) in tomographic PIV or particle tracking. It will be shown that for double-frame applications this new shutter timing outperforms even the latest commercially available single-chip high-speed cameras. (paper)

  17. CCD based beam loss monitor for ion accelerators

    Science.gov (United States)

    Belousov, A.; Mustafin, E.; Ensinger, W.

    2014-04-01

    Beam loss monitoring is an important aspect of proper accelerator functioning. There is a variety of existing solutions, but each has its own disadvantages, e.g. unsuitable dynamic range or time resolution, high cost, or short lifetime. Therefore, new options are looked for. This paper shows a method of application of a charge-coupled device (CCD) video camera as a beam loss monitor (BLM) for ion beam accelerators. The system was tested with a 500 MeV/u N+7 ion beam interacting with an aluminum target. The algorithms of camera signal processing with LabView based code and beam loss measurement are explained. Limits of applicability of this monitor system are discussed.

  18. LiCHy: The CAF’s LiDAR, CCD and Hyperspectral Integrated Airborne Observation System

    OpenAIRE

    Yong Pang; Zengyuan Li; Hongbo Ju; Hao Lu; Wen Jia; Lin Si; Ying Guo; Qingwang Liu; Shiming Li; Luxia Liu; Binbin Xie; Bingxiang Tan; Yuanyong Dian

    2016-01-01

    We describe the design, implementation and performance of a novel airborne system, which integrates commercial waveform LiDAR, CCD (Charge-Coupled Device) camera and hyperspectral sensors into a common platform system. CAF’s (The Chinese Academy of Forestry) LiCHy (LiDAR, CCD and Hyperspectral) Airborne Observation System is a unique system that permits simultaneous measurements of vegetation vertical structure, horizontal pattern, and foliar spectra from different view angles at very high sp...

  19. Measurement of spatial object's exterior attitude based on linear CCD

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    It is difficult to realize real-time measurement of exterior attitude by the traditional systems based on the area image sensor which have conflict between speed and accuracy.The subsystem for three-dimensional (3D) coordinate rcconstruction of point target (S3DCRPT) which is composed of three one-dimensional (1D) cameras based on linear charge-coupled device (CCD) can determine the distant light spots' spatial position. The attitude angle of the measured object is determined by the spatial solution while the coordinate reconstruction is separately carried on by the S3DCRPT with some point cooperation targets (PCTs) on the measured object. A new optical system is designed to solve the interference problem with one-to-one relationship between the PCTs and the S3DCRPT optical subsystems,which improves the measurement accuracy and saves space. The mathematical model of the attitude measurement is established,and partial and global calibrations are realized for the multi-camera attitude measurement system.The test results show the feasibility of the exterior attitude measurement based on linear CCD.

  20. High-definition still image processing system using a new structure CCD sensor

    Science.gov (United States)

    Tamayama, Hiroshi; Saito, Osamu; Inuiya, Masafumi

    2000-05-01

    A new structure CCD sensor has been developed, which can be improved in the image quality compared with the conventional Inter-line Transfer type CCD sensors. The image sensor used in a high-definition image capturing system like a DS camera has been improved to have more number of pixels. This pixel increase adversely affects the sensitivity, dynamic range, signal-to-noise (S/N) ratios. The new CCD sensor has a new pixel arrangement of a half-pitch offset and a new structure of the transfer electrodes, and it achieves to increase sensitivity, dynamic range, S/N and the image quality. The new signal processing system combined with this new CCD has been also developed. It includes high quality analog and digital signal processing LSIs. The newly developed digital signal processing combined with over-sampling technologies enables to achieve higher resolution than conventional cameras with the same number of pixels. The outlines of the new CCD and the signal processing system, the configuration, operations, and the experimental results are described.

  1. CCD research. [design, fabrication, and applications

    Science.gov (United States)

    Gassaway, J. D.

    1976-01-01

    The fundamental problems encountered in designing, fabricating, and applying CCD's are reviewed. Investigations are described and results and conclusions are given for the following: (1) the development of design analyses employing computer aided techniques and their application to the design of a grapped structure; (2) the role of CCD's in applications to electronic functions, in particular, signal processing; (3) extending the CCD to silicon films on sapphire (SOS); and (4) all aluminum transfer structure with low noise input-output circuits. Related work on CCD imaging devices is summarized.

  2. CCD Photometry of M15

    Science.gov (United States)

    Ruelas, A.; Sánchez, L. J.; Herrera, G.; Nigoche-Netro, A.

    2011-10-01

    We present CCD observations of the galactic globular cluster M15, in the B and V filters. The cluster was reasonably covered, except in its northern region where our observations present a gap. We obtained a Hertszprung-Russell (HR) diagram for each region observed, and later we produced a combined HR diagram containing more than 3000 stars. We generate a clean Colour Magnitude Diagram (CMD) and a Super Fiducial Line (SFL). Application of several methods and isochrone fitting leads us to obtain values for the metallicity [Fe/H]_{M15} ˜ -2.16±0.10, the reddening E(B-V)_{M15} ˜ 0.11±0.03, and a distance modulus of [(m-M)_0]_{M15}˜ 15.03.

  3. The Dark Energy Survey Camera

    Science.gov (United States)

    Flaugher, Brenna

    2012-03-01

    The Dark Energy Survey Collaboration has built the Dark Energy Camera (DECam), a 3 square degree, 520 Megapixel CCD camera which is being mounted on the Blanco 4-meter telescope at CTIO. DECam will be used to carry out the 5000 sq. deg. Dark Energy Survey, using 30% of the telescope time over a 5 year period. During the remainder of the time, and after the survey, DECam will be available as a community instrument. Construction of DECam is complete. The final components were shipped to Chile in Dec. 2011 and post-shipping checkout is in progress in Dec-Jan. Installation and commissioning on the telescope are taking place in 2012. A summary of lessons learned and an update of the performance of DECam and the status of the DECam installation and commissioning will be presented.

  4. Robotic CCD microscope for enhanced crystal recognition

    Science.gov (United States)

    Segelke, Brent W.; Toppani, Dominique

    2007-11-06

    A robotic CCD microscope and procedures to automate crystal recognition. The robotic CCD microscope and procedures enables more accurate crystal recognition, leading to fewer false negative and fewer false positives, and enable detection of smaller crystals compared to other methods available today.

  5. Status Of Sofradir IR-CCD Detectors

    Science.gov (United States)

    Tribolet, Philippe; Radisson, Patrick

    1988-05-01

    The topics of this paper deal with the IR-CCD detectors manufactured by SOFRADIR the new French joint venture. Description of the IRCCD technology and the advantages of this approach are given. In conclusion, some IR-CCD typical results are given.

  6. Flat-Field Calibration of CCD Detector for Long Trace Profilers

    International Nuclear Information System (INIS)

    The next generation of synchrotrons and free electron lasers requires x-ray optical systems with extremely high-performance, generally, of diffraction limited quality. Fabrication and use of such optics requires highly accurate metrology. In the present paper, we discuss a way to improve the performance of the Long Trace Profiler (LTP), a slope measuring instrument widely used at synchrotron facilities to characterize x-ray optics at high-spatial-wavelengths from approximately 2 mm to 1 m. One of the major sources of LTP systematic error is the detector. For optimal functionality, the detector has to possess the smallest possible pixel size/spacing, a fast method of shuttering, and minimal non-uniformity of pixel-to-pixel photoresponse. While the first two requirements are determined by choice of detector, the non-uniformity of photoresponse of typical detectors such as CCD cameras is around 2-3 percent. We describe a flat-field calibration setup specially developed for calibration of CCD camera photo-response and dark current with an accuracy of better than 0.5 percent. Such accuracy is adequate for use of a camera as a detector for an LTP with performance of ∼0.1 microradian (rms). We also present the design details of the calibration system and results of calibration of a DALSA CCD camera used for upgrading our LTP-II instrument at the ALS Optical Metrology Laboratory

  7. The Dark Energy Camera (DECam)

    CERN Document Server

    Honscheid, K; Abbott, T; Annis, J; Antonik, M; Barcel, M; Bernstein, R; Bigelow, B; Brooks, D; Buckley-Geer, E; Campa, J; Cardiel, L; Castander, F; Castilla, J; Cease, H; Chappa, S; Dede, E; Derylo, G; Diehl, T; Doel, P; De Vicente, J; Eiting, J; Estrada, J; Finley, D; Flaugher, B; Gaztañaga, E; Gerdes, D; Gladders, M; Guarino, V; Gutíerrez, G; Hamilton, J; Haney, M; Holland, S; Huffman, D; Karliner, I; Kau, D; Kent, S; Kozlovsky, M; Kubik, D; Kühn, K; Kuhlmann, S; Kuk, K; Leger, F; Lin, H; Martínez, G; Martínez, M; Merritt, W; Mohr, J; Moore, P; Moore, T; Nord, B; Ogando, R; Olsen, J; Onal, B; Peoples, J; Qian, T; Roe, N; Sánchez, E; Scarpine, V; Schmidt, R; Schmitt, R; Schubnell, M; Schultz, K; Selen, M; Shaw, T; Simaitis, V; Slaughter, J; Smith, C; Spinka, H; Stefanik, A; Stuermer, W; Talaga, R; Tarle, G; Thaler, J; Tucker, D; Walker, A; Worswick, S; Zhao, A

    2008-01-01

    In this paper we describe the Dark Energy Camera (DECam), which will be the primary instrument used in the Dark Energy Survey. DECam will be a 3 sq. deg. mosaic camera mounted at the prime focus of the Blanco 4m telescope at the Cerro-Tololo International Observatory (CTIO). It consists of a large mosaic CCD focal plane, a five element optical corrector, five filters (g,r,i,z,Y), a modern data acquisition and control system and the associated infrastructure for operation in the prime focus cage. The focal plane includes of 62 2K x 4K CCD modules (0.27"/pixel) arranged in a hexagon inscribed within the roughly 2.2 degree diameter field of view and 12 smaller 2K x 2K CCDs for guiding, focus and alignment. The CCDs will be 250 micron thick fully-depleted CCDs that have been developed at the Lawrence Berkeley National Laboratory (LBNL). Production of the CCDs and fabrication of the optics, mechanical structure, mechanisms, and control system for DECam are underway; delivery of the instrument to CTIO is scheduled ...

  8. CMOS Imaging Sensor Technology for Aerial Mapping Cameras

    Science.gov (United States)

    Neumann, Klaus; Welzenbach, Martin; Timm, Martin

    2016-06-01

    In June 2015 Leica Geosystems launched the first large format aerial mapping camera using CMOS sensor technology, the Leica DMC III. This paper describes the motivation to change from CCD sensor technology to CMOS for the development of this new aerial mapping camera. In 2002 the DMC first generation was developed by Z/I Imaging. It was the first large format digital frame sensor designed for mapping applications. In 2009 Z/I Imaging designed the DMC II which was the first digital aerial mapping camera using a single ultra large CCD sensor to avoid stitching of smaller CCDs. The DMC III is now the third generation of large format frame sensor developed by Z/I Imaging and Leica Geosystems for the DMC camera family. It is an evolution of the DMC II using the same system design with one large monolithic PAN sensor and four multi spectral camera heads for R,G, B and NIR. For the first time a 391 Megapixel large CMOS sensor had been used as PAN chromatic sensor, which is an industry record. Along with CMOS technology goes a range of technical benefits. The dynamic range of the CMOS sensor is approx. twice the range of a comparable CCD sensor and the signal to noise ratio is significantly better than with CCDs. Finally results from the first DMC III customer installations and test flights will be presented and compared with other CCD based aerial sensors.

  9. A Simple Illustrative Model of a Charge-Coupled Device (CCD)

    Science.gov (United States)

    Santillo, Michael F.

    2009-10-01

    Many students (as well as the general public) use modern technology without an understanding of how these devices actually work. They are what scientists refer to in the laboratory as "black boxes." Students often wonder how physics relates to the technology used in the real world and are interested in such applications. An example of one such "black box" is the charge-coupled device (CCD), an electronic imaging sensor invented in 1970 by Bell Labs researchers Willard Boyle and George Smith. Astronomers first embraced CCD technology in the early 1980s because CCDs are very light sensitive, consume low amounts of power, and generate digital images quickly. More than three decades later, CCDs have become ubiquitous, as they are found in consumer digital cameras, scanners, photocopiers, medical imaging devices and spectroscopic detectors. This paper presents a model of a CCD "chip" that can be easily adapted as a classroom demonstration.

  10. Imaging the Moon II: Webcam CCD observations & analysis (a two week lab for non-majors)

    OpenAIRE

    Sato, Takashi

    2013-01-01

    Presented is a successful two week lab involving real sky observations of the Moon in which students make telescopic observations and analyze their own images. Originally developed around the 35 mm film camera as a common household object adapted for astronomical work, the lab transitioned to use the webcam as film photography evolved into an obscure specialty technology and increasing numbers of students had little familiarity with it. The printed circuit board with the CCD is harvested from...

  11. The second US Naval Observatory CCD Astrograph Catalog (UCAC2)

    CERN Document Server

    Zacharias, N; Zacharias, M I; Wycoff, G L; Hall, D M; Monet, D G; Rafferty, T J

    2004-01-01

    The second USNO CCD Astrograph Catalog, UCAC2 was released in July 2003. Positions and proper motions for 48,330,571 sources (mostly stars) are available on 3 CDs, supplemented with 2MASS photometry for 99.5% of the sources. The catalog covers the sky area from -90 to +40 degrees declination, going up to +52 in some areas; this completely supersedes the UCAC1 released in 2001. Current epoch positions are obtained from observations with the USNO 8-inch Twin Astrograph equipped with a 4k CCD camera. The precision of the positions are 15 to 70 mas, depending on magnitude, with estimated systematic errors of 10 mas or below. Proper motions are derived by utilizing over 140 ground-and space-based catalogs, including Hipparcos/Tycho, the AC2000.2, as well as yet unpublished re-measures of the AGK2 plates and scans from the NPM and SPM plates. Proper motion errors are about 1 to 3 mas/yr for stars to 12th magnitude, and about 4 to 7 mas/yr for fainter stars to 16th magnitude. The observational data, astrometric redu...

  12. Pengembangan Metoda Deteksi Rintangan untuk Traktor tanpa Awak Menggunakan Kamera CCD

    OpenAIRE

    Usman Ahmad; Desrial; Mudho Saksono

    2012-01-01

    For unmanned tractor guided by global positioning system, ability for eluding obstacles such as trees, big stone, cavity, bund, people, and other objects in the work area is very important in order not to stop the operation.Surrounding detection system using CCD camera makes it possible for unmanned tractor to detect obstacles in front of it realtime. However, with so many different objects that may captured by the camera, it will need a lot of image processing steps that takes a lot of time ...

  13. Radiation effects on CCD image sensors

    International Nuclear Information System (INIS)

    In the past decade, the micro process technology has advanced and some elaborate semiconductor devices with many microscopic elements in a cell of about 10 μm x 10 μm can be successfully used as radiation detectors and related parts in the field of nuclear physics and engineering. A CCD image sensor, for example, effectively measures details of particle-beam profiles in accelerator applications. This paper describes radiation effects on CCD image sensors. Some CCD samples were irradiated with 60Co gamma-rays and DD and DT neutrons for the examination of the reliability of CCDs used in radiation environments. This paper shows experimental data on radiation effects on CCDs and then discusses the difference in the radiation effects between gamma-rays and neutrons. The following two radiation effects on CCDs are described. One is the transient effect, which is induced by the ionisation process of radiations and is not permanent but recoverable. A CCD responds to radiations as well as light and outputs pseudo signals induced by radiation reactions in the normal video signals during irradiation. The other is the permanent effect, which is caused by the generation of the defects. A CCD image sensor is easily influenced by the trapped holes produced by ionisation in the gate oxide. The defects cause the generation of the leakage current within the depletion region, the trapping of signal charge within the channel of the charge shift register, and the flat band voltage shift which affects the CCD operating bias. (author)

  14. Hemispherical Laue camera

    Science.gov (United States)

    Li, James C. M.; Chu, Sungnee G.

    1980-01-01

    A hemispherical Laue camera comprises a crystal sample mount for positioning a sample to be analyzed at the center of sphere of a hemispherical, X-radiation sensitive film cassette, a collimator, a stationary or rotating sample mount and a set of standard spherical projection spheres. X-radiation generated from an external source is directed through the collimator to impinge onto the single crystal sample on the stationary mount. The diffracted beam is recorded on the hemispherical X-radiation sensitive film mounted inside the hemispherical film cassette in either transmission or back-reflection geometry. The distances travelled by X-radiation diffracted from the crystal to the hemispherical film are the same for all crystal planes which satisfy Bragg's Law. The recorded diffraction spots or Laue spots on the film thereby preserve both the symmetry information of the crystal structure and the relative intensities which are directly related to the relative structure factors of the crystal orientations. The diffraction pattern on the exposed film is compared with the known diffraction pattern on one of the standard spherical projection spheres for a specific crystal structure to determine the orientation of the crystal sample. By replacing the stationary sample support with a rotating sample mount, the hemispherical Laue camera can be used for crystal structure determination in a manner previously provided in conventional Debye-Scherrer cameras.

  15. Mechanical Design of the LSST Camera

    Energy Technology Data Exchange (ETDEWEB)

    Nordby, Martin; Bowden, Gordon; Foss, Mike; Guiffre, Gary; /SLAC; Ku, John; /Unlisted; Schindler, Rafe; /SLAC

    2008-06-13

    The LSST camera is a tightly packaged, hermetically-sealed system that is cantilevered into the main beam of the LSST telescope. It is comprised of three refractive lenses, on-board storage for five large filters, a high-precision shutter, and a cryostat that houses the 3.2 giga-pixel CCD focal plane along with its support electronics. The physically large optics and focal plane demand large structural elements to support them, but the overall size of the camera and its components must be minimized to reduce impact on the image stability. Also, focal plane and optics motions must be minimized to reduce systematic errors in image reconstruction. Design and analysis for the camera body and cryostat will be detailed.

  16. Distortion of the pixel grid in HST WFC3/UVIS and ACS/WFC CCD detectors and its astrometric correction

    Science.gov (United States)

    Kozhurina-Platais, Vera; Mackenty, John; Golimovski, David; Sirianni, Marco; Borncamp, David; Anderson, Jay; Grogin, Norman

    2016-07-01

    The geometric distortion of the CCD detectors used in the Hubble Space TelescopeWide Field Camera 3 (WFC3) and Advanced Camera for Surveys (ACS) instruments is characterized by both large and fine-scale distortions. The large-scale distortion, due to the complexity of the HST optical assembly, can be modeled by a high-order polynomial. The majority of fine-distortion is inherent to the CCD detectors themselves, which manifests itself as fine-scale, correlated systematic offsets in the residuals from the best-fit polynomial solution. Such systematic offsets across the CCD chip introduce astrometric errors at the level of about 0.1 pix (up to 1.5 μm within the 15 μm pixels). These fine-scale and low-amplitude distortions apparently arise from the spatial irregularities in the pixel grid. For the WFC3/UVIS CCD chips, there is a clear pattern of periodic skew in the lithographic-mask stencil imprinted onto the detector. Similar irregularities in the pixel grid of ACS/WFC CCD chips are even more pronounced by the narrow (68×2048 pixel) lithographic-mask stencil. To remove these distortions, a 2-D correction in the form of a look-up table has been developed using HST images of very dense stellar fields. The post-correction of fine-scale astrometric errors can be removed down to the level of 0.01 pix (0.15 μm) or better.

  17. Vision Sensors and Cameras

    Science.gov (United States)

    Hoefflinger, Bernd

    Silicon charge-coupled-device (CCD) imagers have been and are a specialty market ruled by a few companies for decades. Based on CMOS technologies, active-pixel sensors (APS) began to appear in 1990 at the 1 μm technology node. These pixels allow random access, global shutters, and they are compatible with focal-plane imaging systems combining sensing and first-level image processing. The progress towards smaller features and towards ultra-low leakage currents has provided reduced dark currents and μm-size pixels. All chips offer Mega-pixel resolution, and many have very high sensitivities equivalent to ASA 12.800. As a result, HDTV video cameras will become a commodity. Because charge-integration sensors suffer from a limited dynamic range, significant processing effort is spent on multiple exposure and piece-wise analog-digital conversion to reach ranges >10,000:1. The fundamental alternative is log-converting pixels with an eye-like response. This offers a range of almost a million to 1, constant contrast sensitivity and constant colors, important features in professional, technical and medical applications. 3D retino-morphic stacking of sensing and processing on top of each other is being revisited with sub-100 nm CMOS circuits and with TSV technology. With sensor outputs directly on top of neurons, neural focal-plane processing will regain momentum, and new levels of intelligent vision will be achieved. The industry push towards thinned wafers and TSV enables backside-illuminated and other pixels with a 100% fill-factor. 3D vision, which relies on stereo or on time-of-flight, high-speed circuitry, will also benefit from scaled-down CMOS technologies both because of their size as well as their higher speed.

  18. Space station application of CCD image sensors for x-ray imaging

    International Nuclear Information System (INIS)

    Charge Coupled Device (CCD) type solid state image sensors are employed in a number of space based imaging experiments and will be the basis for a camera system to acquire x-ray diffraction images on board the Space Station. This paper will present the system engineering considerations that led to the selection of CCDs over other x-ray imaging technologies and the design of the camera system. This will include discussion of the special requirements imposed by the space environment and this x-ray crystallography mission. This systems engineering discussion will be followed by a summary of high spatial resolution CCDs that are candidates for this camera, what may become available in the future, and what improvements would make CCDs even more suited to such X-ray imaging applications on the ground as well as in space

  19. Hidden cameras everything you need to know about covert recording, undercover cameras and secret filming

    CERN Document Server

    Plomin, Joe

    2016-01-01

    Providing authoritative information on the practicalities of using hidden cameras to expose abuse or wrongdoing, this book is vital reading for anyone who may use or encounter secret filming. It gives specific advice on using phones or covert cameras and unravels the complex legal and ethical issues that need to be considered.

  20. Proactive PTZ Camera Control

    Science.gov (United States)

    Qureshi, Faisal Z.; Terzopoulos, Demetri

    We present a visual sensor network—comprising wide field-of-view (FOV) passive cameras and pan/tilt/zoom (PTZ) active cameras—capable of automatically capturing closeup video of selected pedestrians in a designated area. The passive cameras can track multiple pedestrians simultaneously and any PTZ camera can observe a single pedestrian at a time. We propose a strategy for proactive PTZ camera control where cameras plan ahead to select optimal camera assignment and handoff with respect to predefined observational goals. The passive cameras supply tracking information that is used to control the PTZ cameras.

  1. A quadrant-CCD star tracker

    Science.gov (United States)

    Clampin, M.; Durrance, S. T.; Barkhouser, R.; Golimowski, D. A.; Wald, A.; Fastie, W. G.; Heidtmann, D. L.; Blouke, Morley M.; Westphal, James A.; Janesick, James R.

    1990-01-01

    The characteristics of a quadrant-CCD designed for pointing and tracking are discussed with reference to its use in an adaptive optics program. The quadrant-CCD is used to correct stellar image motion proceeding from atmospheric turbulence by means of a system in which a sensor measures the image offset and sends data to a high-speed tip/tilt mirror. The design and control of the device are detailed, including four 100-micron-square pixels, the quadrant architecture, controller electronics, and data acquisition computer and interface. The transfer function is set forth in the x and y directions, and transfer curves are shown. A laboratory simulation of random image motion was conducted to evaluate the performance of the quadrant-CCD as an image motion sensor, and the experimental results are presented. The suitability of the quadrant-CCD for space-based pointing and tracking uses is demonstrated by this test and two earlier theoretical studies. Some future developments which improve performance capabilities are mentioned.

  2. Robust CCD photoelectric autocollimator for outdoor use

    Institute of Scientific and Technical Information of China (English)

    Min Gao; Zuoren Dong; Zhenglan Bian; Qing Ye; Zujie Fang; Ronghui Qu

    2011-01-01

    A robust charge-coupled device (CCD) photoelectric autocollimator for outdoor use is designed and demonstrated. The influence of outdoor conditions on the signal-to-noise ratio (SNR) and imaging quality of the measuring system is experimentally analyzed. The pulse width modulation technology is applied to the automatic feedback control of the actively regulated illuminating light source of the measuring system to maximize SNR while avoiding image saturation. A Fourier phase shift method for subpixel estimation is adopted to achieve high-accuracy measurement in the presence of noises. Experimental results indicate that the technologies proposed here largely improve the measuring stability, dynamic range, and accuracy of the CCD photoelectric autocollimator used outdoors.%@@ A robust charge-coupled device(CCD)photoelectric autocollimator for outdoor use is designed and demonstrated.The influence of outdoor conditions on the signal-to-noise ratio(SNR)and imaging quality of the measuring system is experimentally analyzed.The pulse width modulation technology is applied to the automatic feedback control of the actively regulated illuminating light source of the measuring system to maximize SNR while avoiding image saturation.A Fourier phase shift method for subpixel estimation is adopted to achieve high-accuracy measurement in the presence of noises.Experimental results indicate that the technologies proposed here largely improve the measuring stability,dynamic range,and accuracy of the CCD photoelectric autocollimator used outdoors.

  3. X-ray imaging using digital cameras

    Science.gov (United States)

    Winch, Nicola M.; Edgar, Andrew

    2012-03-01

    The possibility of using the combination of a computed radiography (storage phosphor) cassette and a semiprofessional grade digital camera for medical or dental radiography is investigated. We compare the performance of (i) a Canon 5D Mk II single lens reflex camera with f1.4 lens and full-frame CMOS array sensor and (ii) a cooled CCD-based camera with a 1/3 frame sensor and the same lens system. Both systems are tested with 240 x 180 mm cassettes which are based on either powdered europium-doped barium fluoride bromide or needle structure europium-doped cesium bromide. The modulation transfer function for both systems has been determined and falls to a value of 0.2 at around 2 lp/mm, and is limited by light scattering of the emitted light from the storage phosphor rather than the optics or sensor pixelation. The modulation transfer function for the CsBr:Eu2+ plate is bimodal, with a high frequency wing which is attributed to the light-guiding behaviour of the needle structure. The detective quantum efficiency has been determined using a radioisotope source and is comparatively low at 0.017 for the CMOS camera and 0.006 for the CCD camera, attributed to the poor light harvesting by the lens. The primary advantages of the method are portability, robustness, digital imaging and low cost; the limitations are the low detective quantum efficiency and hence signal-to-noise ratio for medical doses, and restricted range of plate sizes. Representative images taken with medical doses are shown and illustrate the potential use for portable basic radiography.

  4. Calibrating Images from the MINERVA Cameras

    Science.gov (United States)

    Mercedes Colón, Ana

    2016-01-01

    The MINiature Exoplanet Radial Velocity Array (MINERVA) consists of an array of robotic telescopes located on Mount Hopkins, Arizona with the purpose of performing transit photometry and spectroscopy to find Earth-like planets around Sun-like stars. In order to make photometric observations, it is necessary to perform calibrations on the CCD cameras of the telescopes to take into account possible instrument error on the data. In this project, we developed a pipeline that takes optical images, calibrates them using sky flats, darks, and biases to generate a transit light curve.

  5. Behavior of skin color under varying illumination seen by different cameras at different color spaces

    Science.gov (United States)

    Martinkauppi, J. Birgitta; Soriano, Maricor N.; Laaksonen, Mika V.

    2001-04-01

    The appearance of skin colors in the images depends among other things, on the camera, the calibration of the camera, and the illumination under which the image was taken. In this study, we investigate how the skin colors appear in the chromaticity coordinates of different color spaces like HSV/HSL, normalized rgb, YES and TSL. For this purpose, we have taken images of faces under 16 different illumination/camera calibration conditions using simulated illuminants (Horizon, A, fluorescent TL84 and daylight) with different RGB cameras (1CCD web cameras and a 3CCD camera). In the making of this series of 16 images, first the selected camera was calibrated to one of the four light sources and an image was taken. After that the light source was changed to the other light sources and at each time the person was imaged. The process was repeated to the other two light sources. The same procedure was done for all four light sources and for each camera. The skin regions were extracted from these images and this skin data was then converted to different color spaces. We inspected how the chromaticities of different skin color groups in these color spaces overlap in images taken in all 16 different cases and only in those cases in which the selected camera was calibrated to the current illuminant. These investigations were also made between different cameras. In addition to this, we examined the overlapping of all skin chromaticities from the different skin color groups between cameras.

  6. Improvement in the light sensitivity of the ultrahigh-speed high-sensitivity CCD with a microlens array

    Science.gov (United States)

    Hayashida, T.,; Yonai, J.; Kitamura, K.; Arai, T.; Kurita, T.; Tanioka, K.; Maruyama, H.; Etoh, T. Goji; Kitagawa, S.; Hatade, K.; Yamaguchi, T.; Takeuchi, H.; Iida, K.

    2008-02-01

    We are advancing the development of ultrahigh-speed, high-sensitivity CCDs for broadcast use that are capable of capturing smooth slow-motion videos in vivid colors even where lighting is limited, such as at professional baseball games played at night. We have already developed a 300,000 pixel, ultrahigh-speed CCD, and a single CCD color camera that has been used for sports broadcasts and science programs using this CCD. However, there are cases where even higher sensitivity is required, such as when using a telephoto lens during a baseball broadcast or a high-magnification microscope during science programs. This paper provides a summary of our experimental development aimed at further increasing the sensitivity of CCDs using the light-collecting effects of a microlens array.

  7. Flat-Field Calibration of CCD Detector for Long TraceProfilers

    Energy Technology Data Exchange (ETDEWEB)

    Kirschman, Jonathan L.; Domning, Edward E.; Franck, Keith D.; Irick, Steve C.; MacDowell, Alastair A.; McKinney, Wayne R.; Morrison,Gregory Y.; Smith, Brian V.; Warwick, Tony; Yashchuk, Valeriy V.

    2007-07-31

    The next generation of synchrotrons and free electron lasersrequires x-ray optical systems with extremely high-performance,generally, of diffraction limited quality. Fabrication and use of suchoptics requires highly accurate metrology. In the present paper, wediscuss a way to improve the performance of the Long Trace Profiler(LTP), a slope measuring instrument widely used at synchrotron facilitiesto characterize x-ray optics at high-spatial-wavelengths fromapproximately 2 mm to 1 m. One of the major sources of LTP systematicerror is the detector. For optimal functionality, the detector has topossess the smallest possible pixel size/spacing, a fast method ofshuttering, and minimal non-uniformity of pixel-to-pixel photoresponse.While the first two requirements are determined by choice of detector,the non-uniformity of photoresponse of typical detectors such as CCDcameras is around 2-3 percent. We describe a flat-field calibration setupspecially developed for calibration of CCD camera photo-response and darkcurrent with an accuracy of better than 0.5 percent. Such accuracy isadequate for use of a camera as a detector for an LTP with performance of~;0.1 microradian (rms). We also present the design details of thecalibration system and results of calibration of a DALSA CCD camera usedfor upgrading our LTP-II instrument at the ALS Optical MetrologyLaboratory.

  8. Pengembangan Metoda Deteksi Rintangan untuk Traktor tanpa Awak Menggunakan Kamera CCD

    Directory of Open Access Journals (Sweden)

    Usman Ahmad

    2012-04-01

    Full Text Available For unmanned tractor guided by global positioning system, ability for eluding obstacles such as trees, big stone, cavity, bund, people, and other objects in the work area is very important in order not to stop the operation.Surrounding detection system using CCD camera makes it possible for unmanned tractor to detect obstacles in front of it realtime. However, with so many different objects that may captured by the camera, it will need a lot of image processing steps that takes a lot of time so it is no longer suitable for realtime detection in application. The proposed research is aimed to develop a simpler obstacle detection method by adding a red laser pointer to the CCD camera used to capture scene in front of the tractor. The red laser light that reflected by an obstacle gives an important information in the image, and the distance of the obstacle could be calculated based on phytagoras theory. The results showed that all obstacles with 1 m distance, 80% obstacles with 2 m distance, and 40% obstacles with 3 m distance could be detected. Obstacles with more than 3 m distances could not be detected due to weak laser light for the distances. The accuracy of distance prediction for all situation is 67.5%, which is still need improvements.

  9. True RGB line-scan camera for color machine vision applications

    Science.gov (United States)

    Lemstrom, Guy F.

    1994-10-01

    The design and technical capabilities of a true RGB 3 CCD chip color line scan camera are presented within this paper. The camera was developed for accurate color monitoring and analysis in industrial applications. A black & white line scan camera has been designed and built utilizing the same modular architecture of the color line scan camera. Color separation is made possible with a tri-chromatic RGB beam splitter. Three CCD linear arrays are precisely mounted to the output surfaces of the prism and the outputs of each CCD are exactly matched pixel by pixel. The beam splitter prism can be tailored to separate other spectral components than the standard RGB. A typical CCD can detect between 200 and 100 nm. Either two or three spectral regions can be separated using a beam splitter prism. The camera is totally digital and has a 16-bit parallel computer interface to communicate with a signal processing board. Because of the open architecture of the camera it's possible for the customer to design a board with some special functions handling the preprocessing of the data (for example RGB - HSI conversion). The camera can also be equipped with a high speed CPU-board with enough of local memory to do some image processing inside the camera before sending the data forward. The camera has been used in real industrial applications and has proven that its high resolution and high dynamic range can be used to measure minute color differences, enabling the separation or grading of objects such as minerals, food or other materials that could not otherwise be measured with a black and white camera.

  10. Air Quality Monitoring Using CCD/ CMOS Devices

    OpenAIRE

    Low, Khee Lam; Joanna, Tan Choay Ee; Sim, Keat; Jafri, Mohd Zubir Mat; and, Khiruddin Abdullah

    2010-01-01

    In this chapter, we showed a method for measuring of the air quality index by using the CCD/CMOS sensor. We showed two examples to obtain index values by using webcam and CCTV. Both devices provided a high correlation between the measured and estimated PM10. So, the imaging method is capable to measure PM10 values in the environment. Futher application can be conducted using different devices.

  11. CCD Photometry of Asteroid (147) Protogeneia

    Institute of Scientific and Technical Information of China (English)

    Xi-Liang Zhang; Xiao-Bin Wang; Li-Yun Zhang

    2006-01-01

    We measured the light-curve of the asteroid (147) Protogeneia in November 2004, with a CCD detector attached to the 1-meter telescope at the Yunnan Observatory, China. The synodic period and maximum amplitude of (147) at this apparition are 7.852 hours and 0.25 mag, respectively. The value of a/b for (147), from a preliminary estimation, is not less than 1.26:1.

  12. [A quickly atmospheric correction method for HJ-1 CCD with deep blue algorithm].

    Science.gov (United States)

    Wang, Zhong-Ting; Wang, Hong-Mei; Li, Qing; Zhao, Shao-Hua; Li, Shen-Shen; Chen, Liang-Fu

    2014-03-01

    In the present, for the characteristic of HJ-1 CCD camera, after receiving aerosol optical depth (AOD) from deep blue algorithm which was developed by Hsu et al. assisted by MODerate-resolution imaging spectroradiometer (MODIS) surface reflectance database, bidirectional reflectance distribution function (BRDF) correction with Kernel-Driven Model, and the calculation of viewing geometry with auxiliary data, a new atmospheric correction method of HJ-1 CCD was developed which can be used over vegetation, soil and so on. And, when the CCD data is processed to correct atmospheric influence, with look up table (LUT) and bilinear interpolation, atmospheric correction of HJ-1 CCD is completed quickly by grid calculation of atmospheric parameters and matrix operations of interface define language (IDL). The experiment over China North Plain on July 3rd, 2012 shows that by our method, the atmospheric influence was corrected well and quickly (one CCD image of 1 GB can be corrected in eight minutes), and the reflectance after correction over vegetation and soil was close to the spectrum of vegetation and soil. The comparison with MODIS reflectance product shows that for the advantage of high resolution, the corrected reflectance image of HJ-1 is finer than that of MODIS, and the correlation coefficient of the reflectance over typical surface is greater than 0.9. Error analysis shows that the recognition error of aerosol type leads to 0. 05 absolute error of surface reflectance in near infrared band, which is larger than that in visual bands, and the 0. 02 error of reflectance database leads to 0.01 absolute error of surface reflectance of atmospheric correction in green and red bands. PMID:25208402

  13. Blind identification of cellular phone cameras

    Science.gov (United States)

    Çeliktutan, Oya; Avcibas, Ismail; Sankur, Bülent

    2007-02-01

    In this paper, we focus on blind source cell-phone identification problem. It is known various artifacts in the image processing pipeline, such as pixel defects or unevenness of the responses in the CCD sensor, black current noise, proprietary interpolation algorithms involved in color filter array [CFA] leave telltale footprints. These artifacts, although often imperceptible, are statistically stable and can be considered as a signature of the camera type or even of the individual device. For this purpose, we explore a set of forensic features, such as binary similarity measures, image quality measures and higher order wavelet statistics in conjunction SVM classifier to identify the originating cell-phone type. We provide identification results among 9 different brand cell-phone cameras. In addition to our initial results, we applied a set of geometrical operations to original images in order to investigate how much our proposed method is robust under these manipulations.

  14. High speed single charge coupled device Cranz-Schardin camera

    Science.gov (United States)

    Deblock, Y.; Ducloux, O.; Derbesse, L.; Merlen, A.; Pernod, P.

    2007-03-01

    This article describes an ultrahigh speed visualization system based on a miniaturization of the Cranz-Schardin principle. It uses a set of high power light emitting diodes (LEDs) (Golden Dragon) as the light source and a highly sensitive charge coupled device (CCD) camera for reception. Each LED is fired in sequence and images the refraction index variation between two relay lenses, on a partial region of a CCD image sensor. The originality of this system consists in achieving several images on a single CCD during a frame time. The number of images is 4. The time interval between successive firings determines the speed of the imaging system. This time lies from 100nsto10μs. The light pulse duration lies from 100nsto10μs. The principle and the optical and electronic parts of such a system are described. As an example, some images of acoustic waves propagating in water are presented.

  15. PSF and MTF Measurement Methods for Thick CCD Sensor Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Takacs, P.Z.; Kotov, I.; Frank, J.; O' Connor, P.; Radeka, V.; Lawrence, D.M.

    2010-06-30

    Knowledge of the point spread function (PSF) of the sensors to be used in the Large Synoptic Survey Telescope (LSST) camera is essential for optimal extraction of subtle galaxy shape distortions caused by gravitational weak lensing. We have developed a number of techniques for measuring the PSF of candidate CCD sensors to be used in the LSST camera, each with its own strengths and weaknesses. The two main optical PSF measurement techniques that we use are the direct Virtual Knife Edge (VKE) scan as developed by Karcher, et al. and the indirect interference fringe method after Andersen and Sorensen that measures the modulation transfer function (MTF) directly. The PSF is derived from the MTF by Fourier transform. Other non-optical PSF measurement techniques that we employ include {sup 55}Fe x-ray cluster image size measurements and statistical distribution analysis, and cosmic ray muon track size measurements, but are not addressed here. The VKE technique utilizes a diffraction-limited spot produced by a Point-Projection Microscope (PPM) that is scanned across the sensor with sub-pixel resolution. This technique closely simulates the actual operating condition of the sensor in the telescope with the source spot size having an f/number close to the actual telescope design value. The interference fringe method uses a simple equal-optical-path Michelson-type interferometer with a single-mode fiber source that produces interference fringes with 100% contrast over a wide spatial frequency range sufficient to measure the MTF of the sensor directly. The merits of each measurement technique and results from the various measurement techniques on prototype LSST sensors are presented and compared.

  16. A comparison of CsI:Tl and GOS in a scintillator-CCD detector for nuclear medicine imaging

    Science.gov (United States)

    Bugby, S. L.; Jambi, L. K.; Lees, J. E.

    2016-09-01

    A number of portable gamma cameras for medical imaging use scintillator-CCD based detectors. This paper compares the performance of a scintillator-CCD based portable gamma camera with either a columnar CsI:Tl or a pixelated GOS scintillator installed. The CsI:Tl scintillator has a sensitivity of 40% at 140.5 keV compared to 54% with the GOS scintillator. The intrinsic spatial resolution of the pixelated GOS detector was 1.09 mm, over 4 times poorer than for CsI:Tl. Count rate capability was also found to be significantly lower when the GOS scintillator was used. The uniformity was comparable for both scintillators.

  17. Characteristic analysis on the thermal noise of infrared CCD

    Science.gov (United States)

    Zhang, Rong-zhu; Yu, Xing; Liu, Guo-dong

    2014-09-01

    1.064 μm, 1.319 μm and 10.6 μm laser were used to irradiate silicon-based HgCdTe CCD image system. The temperature distribution of detector induced by infrared laser irradiating in the experiment above was simulated. The influence of temperature on photoelectric parameters of HgCdTe CCD was calculated. A CCD physical model of crosstalk saturation was built and the response characteristic of CCD under the influence of thermal noise was analyzed. Result indicated that the rise of temperature induced by laser irradiating little influenced imaging effect of CCD.

  18. Radiation Dose-Rate Extraction from the Camera Image of Quince 2 Robot System using Optical Character Recognition

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jai Wan; Jeong, Kyung Min [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    In the case of the Japanese Quince 2 robot system, 7 CCD/CMOS cameras were used. 2 CCD cameras of Quince robot are used for the forward and backward monitoring of the surroundings during navigation. And 2 CCD (or CMOS) cameras are used for monitoring the status of front-end and back-end motion mechanics such as flippers and crawlers. A CCD camera with wide field of view optics is used for monitoring the status of the communication (VDSL) cable reel. And another 2 CCD cameras are assigned for reading the indication value of the radiation dosimeter and the instrument. The Quince 2 robot measured radiation in the unit 2 reactor building refueling floor of the Fukushima nuclear power plant. The CCD camera with wide field-of-view (fisheye) lens reads indicator of the dosimeter loaded on the Quince 2 robot, which was sent to carry out investigating the unit 2 reactor building refueling floor situation. The camera image with gamma ray dose-rate information is transmitted to the remote control site via VDSL communication line. At the remote control site, the radiation information in the unit 2 reactor building refueling floor can be perceived by monitoring the camera image. To make up the radiation profile in the surveyed refueling floor, the gamma ray dose-rate information in the image should be converted to numerical value. In this paper, we extract the gamma ray dose-rate value in the unit 2 reactor building refueling floor using optical character recognition method

  19. Vacuum Camera Cooler

    Science.gov (United States)

    Laugen, Geoffrey A.

    2011-01-01

    Acquiring cheap, moving video was impossible in a vacuum environment, due to camera overheating. This overheating is brought on by the lack of cooling media in vacuum. A water-jacketed camera cooler enclosure machined and assembled from copper plate and tube has been developed. The camera cooler (see figure) is cup-shaped and cooled by circulating water or nitrogen gas through copper tubing. The camera, a store-bought "spy type," is not designed to work in a vacuum. With some modifications the unit can be thermally connected when mounted in the cup portion of the camera cooler. The thermal conductivity is provided by copper tape between parts of the camera and the cooled enclosure. During initial testing of the demonstration unit, the camera cooler kept the CPU (central processing unit) of this video camera at operating temperature. This development allowed video recording of an in-progress test, within a vacuum environment.

  20. Making Ceramic Cameras

    Science.gov (United States)

    Squibb, Matt

    2009-01-01

    This article describes how to make a clay camera. This idea of creating functional cameras from clay allows students to experience ceramics, photography, and painting all in one unit. (Contains 1 resource and 3 online resources.)

  1. Constrained space camera assembly

    Science.gov (United States)

    Heckendorn, Frank M.; Anderson, Erin K.; Robinson, Casandra W.; Haynes, Harriet B.

    1999-01-01

    A constrained space camera assembly which is intended to be lowered through a hole into a tank, a borehole or another cavity. The assembly includes a generally cylindrical chamber comprising a head and a body and a wiring-carrying conduit extending from the chamber. Means are included in the chamber for rotating the body about the head without breaking an airtight seal formed therebetween. The assembly may be pressurized and accompanied with a pressure sensing means for sensing if a breach has occurred in the assembly. In one embodiment, two cameras, separated from their respective lenses, are installed on a mounting apparatus disposed in the chamber. The mounting apparatus includes means allowing both longitudinal and lateral movement of the cameras. Moving the cameras longitudinally focuses the cameras, and moving the cameras laterally away from one another effectively converges the cameras so that close objects can be viewed. The assembly further includes means for moving lenses of different magnification forward of the cameras.

  2. Preliminary evaluation of charge-coupled device (CCD) multispectral analysis in ophthalmology

    International Nuclear Information System (INIS)

    The work described was originally aimed at providing a new diagnostic technique for the early detection of malignant ocular tumors through their spectral signature. The instrument developed comprises a modified fundus camera, a Charge-coupled device (CCD) camera and a 16 bit microcomputer equipped with floopy disk drives and a 512 x 512 x 8-bit display device. The system allows the recording of digitized fundus or iris reflectance pictures in eight spectral bands between 500 and 1100 nm. After calibration and preprocessing of the data, a multispectral analysis is performed by means of a VAX computer. The image processing methods are described and their ability to characterize pigmented lesions or other ocular anatomical features through their spectral signature is evaluated

  3. A microprocessor-controlled CCD star tracker

    Science.gov (United States)

    Salomon, P. M.; Goss, W. C.

    1976-01-01

    The STELLAR (Star Tracker for Economical Long Life Attitude Reference) utilizes an image sensing Charge-Coupled Device (CCD) operating under microprocessor control. This approach results in a new type of high-accuracy star tracker which can be adapted to a wide variety of different space flight applications through software changes only. The STELLAR determines two-axis star positions by computing the element and the interelement interpolated centroid positions of the star images. As many as 10 stars may be tracked simultaneously, providing significantly increased stability and accuracy. A detailed description of the STELLAR is presented along with measurements of system performance obtained from an operating breadboard model.

  4. Ghost Images in Schmidt CCD Photometry

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The wide field of the Schmidt telescope implies a greater chance of the field containing bright objects, and the presence of a corrector lens produces a certain type of ghost images. We summarize and confirm the features of such ghost images in Schmidt CCD photometry. The ghost images could be star-like under special observational conditions. The zenith distance of the telescope, among other factors, is found to correlate with different patterns of the ghost images. Some relevant issues are discussed and possible applications of our results are suggested.

  5. Harpicon camera for HDTV

    Science.gov (United States)

    Tanada, Jun

    1992-08-01

    Ikegami has been involved in broadcast equipment ever since it was established as a company. In conjunction with NHK it has brought forth countless television cameras, from black-and-white cameras to color cameras, HDTV cameras, and special-purpose cameras. In the early days of HDTV (high-definition television, also known as "High Vision") cameras the specifications were different from those for the cameras of the present-day system, and cameras using all kinds of components, having different arrangements of components, and having different appearances were developed into products, with time spent on experimentation, design, fabrication, adjustment, and inspection. But recently the knowhow built up thus far in components, , printed circuit boards, and wiring methods has been incorporated in camera fabrication, making it possible to make HDTV cameras by metbods similar to the present system. In addition, more-efficient production, lower costs, and better after-sales service are being achieved by using the same circuits, components, mechanism parts, and software for both HDTV cameras and cameras that operate by the present system.

  6. Digital Pinhole Camera

    Science.gov (United States)

    Lancor, Rachael; Lancor, Brian

    2014-01-01

    In this article we describe how the classic pinhole camera demonstration can be adapted for use with digital cameras. Students can easily explore the effects of the size of the pinhole and its distance from the sensor on exposure time, magnification, and image quality. Instructions for constructing a digital pinhole camera and our method for…

  7. Auto-Guiding System for CQUEAN (Camera for QUasars in EArly uNiverse)

    CERN Document Server

    Kim, Eunbin; Jeong, Hyenju; Kim, Jinyoung; Kuehne, John; Kim, Dong Han; Kim, Han Geun; Odons, Peter S; Chang, Seunghyuk; Im, Myungshin; Pak, Soojong

    2011-01-01

    To perform imaging observation of optically red objects such as high redshift quasars and brown dwarfs, the Center for the Exploration of the Origin of the Universe (CEOU) recently developed an optical CCD camera, Camera for QUasars in EArly uNiverse(CQUEAN), which is sensitive at 0.7-1.1 um. To enable observations with long exposures, we developed an auto-guiding system for CQUEAN. This system consist of an off-axis mirror, a baffle, a CCD camera, a motor and a differential decelerator. To increase the number of available guiding stars, we designed a rotating mechanism for the off-axis guiding camera. The guiding field can be scammed along the 10 acrmin ring offset from the optical axis of the telescope. Combined with the auto-guiding software of the McDonald Observatory, we confirmed that a stable image can be obtained with an exposure time as long as 1200 seconds.

  8. ROSA: a high cadence, synchronized multi-camera solar imaging system

    CERN Document Server

    Jess, D B; Christian, D J; Keenan, F P; Ryans, R S I; Crockett, P J

    2009-01-01

    Rapid Oscillations in the Solar Atmosphere (ROSA) is a synchronized, six camera high cadence solar imaging instrument developed by Queen's University Belfast. The system is available on the Dunn Solar Telescope at the National Solar Observatory in Sunspot, New Mexico, USA as a common-user instrument. Consisting of six 1k x 1k Peltier-cooled frame-transfer CCD cameras with very low noise (0.02-15 e/s/pixel), each ROSA camera is capable of full-chip readout speeds in excess of 30 Hz, or 200 Hz when the CCD is windowed. Combining multiple cameras and fast readout rates, ROSA will accumulate approximately 12 TB of data per 8 hours observing. Following successful commissioning during August 2008, ROSA will allow multi-wavelength studies of the solar atmosphere at high temporal resolution.

  9. CCD image sensor with compensated reset operation

    Science.gov (United States)

    Park, Sangsik; Uh, Hyung Soo; Park, Soeun

    2006-11-01

    A low voltage charge coupled device (CCD) image sensor has been developed by adjusting the electron potential barrier in the electron sensing structure. A charge injection to the gate dielectrics of a MOS transistor was utilized to optimize the electron potential level in the output structure. A DC bias generating circuit was added to the reset structure which sets reference voltage and holds the signal charge to be detected. The generated DC bias is added to the reset pulse to give an optimized voltage margin to the reset operation, and is controlled by adjustment of the threshold voltage of a MOS transistor in the circuit. By the pulse-type stress voltage applied to the gate, the electrons and holes were injected to the gate dielectrics, and the threshold voltage could be adjusted ranging from 0.2 V to 5.5 V, which is suitable for compensating the incomplete reset operation due to the process variation. The charges trapped in the silicon nitride lead to the positive and negative shift of the threshold voltage, and this phenomenon is explained by Poole-Frenkel conduction and Fowler-Nordheim conduction. A CCD image sensor with 492(H) × 510(V) pixels adopting this structure showed complete reset operation with the driving voltage of 3.0 V. The image taken with the image sensor utilizing this structure was not saturated to the illumination of 30 lux, that is, showed no image distortion.

  10. CCD developed for scientific application by Hamamatsu

    CERN Document Server

    Miyaguchi, K; Dezaki, J; Yamamoto, K

    1999-01-01

    We have developed CCDs for scientific applications that feature a low readout noise of less than 5 e-rms and low dark current of 10-25 pA/cm sup 2 at room temperature. CCDs with these characteristics will prove extremely useful in applications such as spectroscopic measurement and dental radiography. In addition, a large-area CCD of 2kx4k pixels and 15 mu m square pixel size has recently been completed for optical use in astronomical observations. Applications to X-ray astronomy require the most challenging device performance in terms of deep depletion, high CTE, and focal plane size, among others. An abuttable X-ray CCD, having 1024x1024 pixels and 24 mu m square pixel size, is to be installed in an international space station (ISS). We are now striving to achieve the lowest usable cooling temperature by means of a built-in TEC with limited power consumption. Details on the development status are described in this report. We would also like to present our future plans for a large active area and deep depleti...

  11. Adapting Virtual Camera Behaviour

    DEFF Research Database (Denmark)

    Burelli, Paolo

    2013-01-01

    In a three-dimensional virtual environment aspects such as narrative and interaction completely depend on the camera since the camera defines the player’s point of view. Most research works in automatic camera control aim to take the control of this aspect from the player to automatically gen......- erate cinematographic game experiences reducing, however, the player’s feeling of agency. We propose a methodology to integrate the player in the camera control loop that allows to design and generate personalised cinematographic expe- riences. Furthermore, we present an evaluation of the afore......- mentioned methodology showing that the generated camera movements are positively perceived by novice asnd intermediate players....

  12. Novel CCD image processor for Z-plane architecture

    Science.gov (United States)

    Kemeny, S. E.; Eid, E.-S.; Fossum, E. R.

    1989-09-01

    The use of charge-coupled device (CCD) circuits in Z-plane architectures for focal-plane image processing is discussed. The low-power, compact layout nature of CCDs makes them attractive for Z-plane application. Three application areas are addressed: non-uniformity compensation using CCD MDAC circuits, neighborhood image processing functions implemented with CCD circuits, and the use of CCDs for buffering multiple image frames. Such buffering enables spatial-temporal image transformation for lossless compression.

  13. Fast measurement of temporal noise of digital camera's photosensors

    Science.gov (United States)

    Cheremkhin, Pavel A.; Evtikhiev, Nikolay N.; Krasnov, Vitaly V.; Rodin, Vladislav G.; Starikov, Rostislav S.; Starikov, Sergey N.

    2015-10-01

    Currently photo- and videocameras are widespread parts of both scientific experimental setups and consumer applications. They are used in optics, radiophysics, astrophotography, chemistry, and other various fields of science and technology such as control systems and video-surveillance monitoring. One of the main information limitations of photoand videocameras are noises of photosensor pixels. Camera's photosensor noise can be divided into random and pattern components. Temporal noise includes random noise component while spatial noise includes pattern noise component. Spatial part usually several times lower in magnitude than temporal. At first approximation spatial noises might be neglected. Earlier we proposed modification of the automatic segmentation of non-uniform targets (ASNT) method for measurement of temporal noise of photo- and videocameras. Only two frames are sufficient for noise measurement with the modified method. In result, proposed ASNT modification should allow fast and accurate measurement of temporal noise. In this paper, we estimated light and dark temporal noises of four cameras of different types using the modified ASNT method with only several frames. These cameras are: consumer photocamera Canon EOS 400D (CMOS, 10.1 MP, 12 bit ADC), scientific camera MegaPlus II ES11000 (CCD, 10.7 MP, 12 bit ADC), industrial camera PixeLink PLB781F (CMOS, 6.6 MP, 10 bit ADC) and video-surveillance camera Watec LCL-902C (CCD, 0.47 MP, external 8 bit ADC). Experimental dependencies of temporal noise on signal value are in good agreement with fitted curves based on a Poisson distribution excluding areas near saturation. We measured elapsed time for processing of shots used for temporal noise estimation. The results demonstrate the possibility of fast obtaining of dependency of camera full temporal noise on signal value with the proposed ASNT modification.

  14. Campaign of sky brightness and extinction measurements using a portable CCD camera

    Science.gov (United States)

    Falchi, Fabio

    2011-03-01

    In this paper, we present the results of a 12-yr campaign devoted to monitoring the sky brightness affected by different levels of light pollution. Different sites characterized by different altitudes and atmospheric transparency have been considered. The standard photometric Johnson B and V bands were used. An extinction measurement was performed for each site and each night, along with a calibration of the instrument. These measurements have allowed us to build sky brightness maps of the hemisphere above each observing site; each map contains up to 200 data points spread around the sky. We have found a stop in zenith sky brightness growth at the two sites where a time series exists. Using zenith sky brightness measurements taken with and without extensive snow coverage, we weighted the importance of direct versus indirect flux in producing sky glow at several sites.

  15. LENS REFLECTOMETRY WITH A CCD VIDEO CAMERA AND COMPUTER IMAGE-ANALYSIS

    NARCIS (Netherlands)

    VANDENBROM, HJB; SIERTSEMA, JV; KOOIJMAN, AC; BLANKSMA, LJ; VANRIJ, G

    1991-01-01

    Lens reflectometry is a useful method of determining the back scatter of light from the cataractous lens. Making use of normal programmes, the personal computer can be used for the quantitative determination of the lens reflex, as seen in the slit-lamp image. If three different images of the same ey

  16. On Relativistic Disk Spectroscopy in Compact Objects with X-ray CCD Cameras

    CERN Document Server

    Miller, J M; Bautz, M W; Bhattacharyya, S; Burrows, D N; Cackett, E M; Fabian, A C; Freyberg, M J; Haberl, F; Kennea, J; Nowak, M A; Reis, R C; Strohmayer, T E; Tsujimoto, M

    2010-01-01

    X-ray charge-coupled devices (CCDs) are the workhorse detectors of modern X-ray astronomy. Typically covering the 0.3-10.0 keV energy range, CCDs are able to detect photoelectric absorption edges and K shell lines from most abundant metals. New CCDs also offer resolutions of 30-50 (E/dE), which is sufficient to detect lines in hot plasmas and to resolve many lines shaped by dynamical processes in accretion flows. The spectral capabilities of X-ray CCDs have been particularly important in detecting relativistic emission lines from the inner disks around accreting neutron stars and black holes. One drawback of X-ray CCDs is that spectra can be distorted by photon "pile-up", wherein two or more photons may be registered as a single event during one frame time. We have conducted a large number of simulations using a statistical model of photon pile-up to assess its impacts on relativistic disk line and continuum spectra from stellar-mass black holes and neutron stars. The simulations cover the range of current X-...

  17. Rayleigh Laser Guide Star Systems: UnISIS Bow Tie Shutter and CCD39 Wavefront Camera

    OpenAIRE

    Thompson, Laird A.; Teare, Scott W.; Crawford, Samuel L.; Leach, Robert W.

    2002-01-01

    Laser guide star systems based on Rayleigh scattering require some means to deal with the flash of low altitude laser light that follows immediately after each laser pulse. These systems also need a fast shutter to isolate the high altitude portion of the focused laser beam to make it appear star-like to the wavefront sensor. We describe how these tasks are accomplished with UnISIS, the Rayleigh laser guided adaptive optics system at the Mt. Wilson Observatory 2.5-m telescope. We use several ...

  18. Resolved CCD Photometry of Pluto and Charon

    International Nuclear Information System (INIS)

    Highly resolved CCD images of Pluto and Charon near maximum separation are measured with point spread function fitting techniques to determine independent magnitudes and an accurate separation for Pluto and Charon. A measured separation of 0.923 + or - 0.005 arcsec at a position angle of 173.3 + or - 0.3 deg on June 18, 1987 UT produced a value of 19558.0 + or - 153.0 km for the radius of Charon's orbit. An apparent B magnitude of 14.877 + or - 0.009 and (B-I) color of 1.770 + or - 0.015 are determined for Pluto, while Charon is fainter with B = 18.826 + or - 0.011 and slightly bluer with (B-I) = 1.632 + or - 0.018. 18 references

  19. Programmable Clock Waveform Generation for CCD Readout

    Energy Technology Data Exchange (ETDEWEB)

    Vicente, J. de; Castilla, J.; Martinez, G.; Marin, J.

    2006-07-01

    Charge transfer efficiency in CCDs is closely related to the clock waveform. In this paper, an experimental framework to explore different FPGA based clock waveform generator designs is described. Two alternative design approaches for controlling the rise/fall edge times and pulse width of the CCD clock signal have been implemented: level-control and time-control. Both approaches provide similar characteristics regarding the edge linearity and noise. Nevertheless, dissimilarities have been found with respect to the area and frequency range of application. Thus, while the time-control approach consumes less area, the level control approach provides a wider range of clock frequencies since it does not suffer capacitor discharge effect. (Author) 8 refs.

  20. New CCD photometry of asteroid (1028) Lydina

    Institute of Scientific and Technical Information of China (English)

    Yi-Bo Wang; Xiao-Bin Wang

    2012-01-01

    New CCD photometric observations for asteroid (1028) Lydina,carried out with the 1-m and 2.4-m telescopes at Yunnan Observatory from 2011 December 19 to 2012 February 3,are presented.Using the new light curves,the rotation period of 11.680±0.001 hours is derived with the Phase Dispersion Minimization (PDM) method.In addition,using the Amplitude-Aspect method,the elementary results of the pole orientation of asteroid (1028) Lydina are obtained:λp= 111°+4°-4°,βp= 31°+4°-5°.Meanwhile,the axial ratios of the tri-axial ellipsoid are estimated:a/b = 1.77+0.10-0.08and b/c = 1.17+0.07-0.09.

  1. Control and protection of outdoor embedded camera for astronomy

    Science.gov (United States)

    Rigaud, F.; Jegouzo, I.; Gaudemard, J.; Vaubaillon, J.

    2012-09-01

    The purpose of CABERNET- Podet-Met (CAmera BEtter Resolution NETwork, Pole sur la Dynamique de l'Environnement Terrestre - Meteor) project is the automated observation, by triangulation with three cameras, of meteor showers to perform a calculation of meteoroids trajectory and velocity. The scientific goal is to search the parent body, comet or asteroid, for each observed meteor. To install outdoor cameras in order to perform astronomy measurements for several years with high reliability requires a very specific design for the box. For these cameras, this contribution shows how we fulfilled the various functions of their boxes, such as cooling of the CCD, heating to melt snow and ice, the protecting against moisture, lightning and Solar light. We present the principal and secondary functions, the product breakdown structure, the technical solutions evaluation grid of criteria, the adopted technology products and their implementation in multifunction subsets for miniaturization purpose. To manage this project, we aim to get the lowest manpower and development time for every part. In appendix, we present the measurements the image quality evolution during the CCD cooling, and some pictures of the prototype.

  2. GRACE star camera noise

    Science.gov (United States)

    Harvey, Nate

    2016-08-01

    Extending results from previous work by Bandikova et al. (2012) and Inacio et al. (2015), this paper analyzes Gravity Recovery and Climate Experiment (GRACE) star camera attitude measurement noise by processing inter-camera quaternions from 2003 to 2015. We describe a correction to star camera data, which will eliminate a several-arcsec twice-per-rev error with daily modulation, currently visible in the auto-covariance function of the inter-camera quaternion, from future GRACE Level-1B product releases. We also present evidence supporting the argument that thermal conditions/settings affect long-term inter-camera attitude biases by at least tens-of-arcsecs, and that several-to-tens-of-arcsecs per-rev star camera errors depend largely on field-of-view.

  3. Microchannel plate streak camera

    Science.gov (United States)

    Wang, Ching L.

    1989-01-01

    An improved streak camera in which a microchannel plate electron multiplier is used in place of or in combination with the photocathode used in prior streak cameras. The improved streak camera is far more sensitive to photons (UV to gamma-rays) than the conventional x-ray streak camera which uses a photocathode. The improved streak camera offers gamma-ray detection with high temporal resolution. It also offers low-energy x-ray detection without attenuation inside the cathode. Using the microchannel plate in the improved camera has resulted in a time resolution of about 150 ps, and has provided a sensitivity sufficient for 1000 KeV x-rays.

  4. Solid state video cameras

    CERN Document Server

    Cristol, Y

    2013-01-01

    Solid State Video Cameras reviews the state of the art in the field of solid-state television cameras as compiled from patent literature. Organized into 10 chapters, the book begins with the basic array types of solid-state imagers and appropriate read-out circuits and methods. Documents relating to improvement of picture quality, such as spurious signal suppression, uniformity correction, or resolution enhancement, are also cited. The last part considerssolid-state color cameras.

  5. Polarization encoded color camera.

    Science.gov (United States)

    Schonbrun, Ethan; Möller, Guðfríður; Di Caprio, Giuseppe

    2014-03-15

    Digital cameras would be colorblind if they did not have pixelated color filters integrated into their image sensors. Integration of conventional fixed filters, however, comes at the expense of an inability to modify the camera's spectral properties. Instead, we demonstrate a micropolarizer-based camera that can reconfigure its spectral response. Color is encoded into a linear polarization state by a chiral dispersive element and then read out in a single exposure. The polarization encoded color camera is capable of capturing three-color images at wavelengths spanning the visible to the near infrared. PMID:24690806

  6. Ringfield lithographic camera

    Science.gov (United States)

    Sweatt, William C.

    1998-01-01

    A projection lithography camera is presented with a wide ringfield optimized so as to make efficient use of extreme ultraviolet radiation from a large area radiation source (e.g., D.sub.source .apprxeq.0.5 mm). The camera comprises four aspheric mirrors optically arranged on a common axis of symmetry with an increased etendue for the camera system. The camera includes an aperture stop that is accessible through a plurality of partial aperture stops to synthesize the theoretical aperture stop. Radiation from a mask is focused to form a reduced image on a wafer, relative to the mask, by reflection from the four aspheric mirrors.

  7. Camera simulation engine enables efficient system optimization for super-resolution imaging

    Science.gov (United States)

    Fullerton, Stephanie; Bennett, Keith; Toda, Eiji; Takahashi, Teruo

    2012-02-01

    Quantitative fluorescent imaging requires optimization of the complete optical system, from the sample to the detector. Such considerations are especially true for precision localization microscopy such as PALM and (d)STORM where the precision of the result is limited by the noise in both the optical and detection systems. Here, we present a Camera Simulation Engine (CSE) that allows comparison of imaging results from CCD, CMOS and EM-CCD cameras under various sample conditions and can accurately validate the quality of precision localization algorithms and camera performance. To achieve these results, the CSE incorporates the following parameters: 1) Sample conditions including optical intensity, wavelength, optical signal shot noise, and optical background shot noise; 2) Camera specifications including QE, pixel size, dark current, read noise, EM-CCD excess noise; 3) Camera operating conditions such as exposure, binning and gain. A key feature of the CSE is that, from a single image (either real or simulated "ideal") we generate a stack of statistically realistic images. We have used the CSE to validate experimental data showing that certain current scientific CMOS technology outperforms EM-CCD in most super-resolution scenarios. Our results support using the CSE to efficiently and methodically select cameras for quantitative imaging applications. Furthermore, the CSE can be used to robustly compare and evaluate new algorithms for data analysis and image reconstruction. These uses of the CSE are particularly relevant to super-resolution precision localization microscopy and provide a faster, simpler and more cost effective means of system optimization, especially camera selection.

  8. True RGB line scan camera for color machine vision applications

    Science.gov (United States)

    Lemstrom, Guy F.

    1994-11-01

    In this paper a true RGB 3-chip color line scan camera is described. The camera was mainly developed for accurate color measuring in industrial applications. Due to the camera's modularity it's also possible to use it as a B/W-camera. The color separation is made with a RGB-beam splitter. The CCD linear arrays are fixed with a high accuracy to the beam splitters output in order to match the pixels of the three different CCDs on each other. This makes the color analyses simple compared to color line arrays where line or pixel matching has to be done. The beam splitter can be custom made to separate spectral components other than standard RGB. The spectral range is from 200 to 1000 nm for most CCDs and two or three spectral areas can be separately measured with the beam splitter. The camera is totally digital and has a 16-bit parallel computer interface to communicate with a signal processing board. Because of the open architecture of the camera it's possible for the customer to design a board with some special functions handling the preprocessing of the data (for example RGB - HSI conversion). The camera can also be equipped with a high speed CPU-board with enough local memory to do some image processing inside the camera before sending the data forward. The camera has been used in real industrial applications and has proven that its high resolution and high dynamic range can be used to measure color differences of small amounts to separate or grade objects such as minerals, food or other materials that can't be measured with a black and white camera.

  9. An efficient image compressor for charge coupled devices camera.

    Science.gov (United States)

    Li, Jin; Xing, Fei; You, Zheng

    2014-01-01

    Recently, the discrete wavelet transforms- (DWT-) based compressor, such as JPEG2000 and CCSDS-IDC, is widely seen as the state of the art compression scheme for charge coupled devices (CCD) camera. However, CCD images project on the DWT basis to produce a large number of large amplitude high-frequency coefficients because these images have a large number of complex texture and contour information, which are disadvantage for the later coding. In this paper, we proposed a low-complexity posttransform coupled with compressing sensing (PT-CS) compression approach for remote sensing image. First, the DWT is applied to the remote sensing image. Then, a pair base posttransform is applied to the DWT coefficients. The pair base are DCT base and Hadamard base, which can be used on the high and low bit-rate, respectively. The best posttransform is selected by the l p -norm-based approach. The posttransform is considered as the sparse representation stage of CS. The posttransform coefficients are resampled by sensing measurement matrix. Experimental results on on-board CCD camera images show that the proposed approach significantly outperforms the CCSDS-IDC-based coder, and its performance is comparable to that of the JPEG2000 at low bit rate and it does not have the high excessive implementation complexity of JPEG2000. PMID:25114977

  10. The great circle camera a new drift scanning instrument

    CERN Document Server

    Zaritsky, D; Bredthauer, G; Zaritsky, Dennis; Shectman, Stephen A; Bredthauer, Gregory

    1995-01-01

    We discuss the design, construction, and use of a new class of scanning camera that eliminates a critical limitation of standard CCD drift-scan observations. A standard scan, which involves no correction for the differential drift rates and curved stellar paths across the field-of-view, suffers from severe image degradation even when one observes at moderate declinations. Not only does this effect limit the area of the sky over which drift scanning is viable, but as detector sizes increase, CCD mosaics become standard, and dome/telescope seeing improves, the area of sky for which scanning is acceptable (image degradation \\ltsim seeing) will be further reduced unless some action is taken. By modifying the scan path (the path on the sky traced by signal accumulated along a single CCD column) to lie along a great circle on the sky rather than along a path of constant declination, image degradation is minimized. In this paper, we discuss the design and implementation of a stage that rotates and translates the CCD...

  11. Camera Operator and Videographer

    Science.gov (United States)

    Moore, Pam

    2007-01-01

    Television, video, and motion picture camera operators produce images that tell a story, inform or entertain an audience, or record an event. They use various cameras to shoot a wide range of material, including television series, news and sporting events, music videos, motion pictures, documentaries, and training sessions. Those who film or…

  12. Cooling the dark energy camera instrument

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, R.L.; Cease, H.; /Fermilab; DePoy, D.; /Ohio State U.; Diehl, H.T.; Estrada, J.; Flaugher, B.; /Fermilab; Kuhlmann, S.; /Ohio State U.; Onal, Birce; Stefanik, A.; /Fermilab

    2008-06-01

    DECam, camera for the Dark Energy Survey (DES), is undergoing general design and component testing. For an overview see DePoy, et al in these proceedings. For a description of the imager, see Cease, et al in these proceedings. The CCD instrument will be mounted at the prime focus of the CTIO Blanco 4m telescope. The instrument temperature will be 173K with a heat load of 113W. In similar applications, cooling CCD instruments at the prime focus has been accomplished by three general methods. Liquid nitrogen reservoirs have been constructed to operate in any orientation, pulse tube cryocoolers have been used when tilt angles are limited and Joule-Thompson or Stirling cryocoolers have been used with smaller heat loads. Gifford-MacMahon cooling has been used at the Cassegrain but not at the prime focus. For DES, the combined requirements of high heat load, temperature stability, low vibration, operation in any orientation, liquid nitrogen cost and limited space available led to the design of a pumped, closed loop, circulating nitrogen system. At zenith the instrument will be twelve meters above the pump/cryocooler station. This cooling system expected to have a 10,000 hour maintenance interval. This paper will describe the engineering basis including the thermal model, unbalanced forces, cooldown time, the single and two-phase flow model.

  13. Thermal Cameras and Applications

    DEFF Research Database (Denmark)

    Gade, Rikke; Moeslund, Thomas B.

    2014-01-01

    Thermal cameras are passive sensors that capture the infrared radiation emitted by all objects with a temperature above absolute zero. This type of camera was originally developed as a surveillance and night vision tool for the military, but recently the price has dropped, significantly opening up...... a broader field of applications. Deploying this type of sensor in vision systems eliminates the illumination problems of normal greyscale and RGB cameras. This survey provides an overview of the current applications of thermal cameras. Applications include animals, agriculture, buildings, gas detection......, industrial, and military applications, as well as detection, tracking, and recognition of humans. Moreover, this survey describes the nature of thermal radiation and the technology of thermal cameras....

  14. Dry imaging cameras

    Directory of Open Access Journals (Sweden)

    I K Indrajit

    2011-01-01

    Full Text Available Dry imaging cameras are important hard copy devices in radiology. Using dry imaging camera, multiformat images of digital modalities in radiology are created from a sealed unit of unexposed films. The functioning of a modern dry camera, involves a blend of concurrent processes, in areas of diverse sciences like computers, mechanics, thermal, optics, electricity and radiography. Broadly, hard copy devices are classified as laser and non laser based technology. When compared with the working knowledge and technical awareness of different modalities in radiology, the understanding of a dry imaging camera is often superficial and neglected. To fill this void, this article outlines the key features of a modern dry camera and its important issues that impact radiology workflow.

  15. Development of automatic data extraction technique from visible CCD images for in-vessel dust study in Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Suk-Ho [National Fusion Research Institute, 113 Gwahangno, YuSung-Gu, DaeJeon 305-333 (Korea, Republic of); Grisolia, Christian; Monier-Garbet, Pascale [Association EURATOM-CEA/DSM/IRFM/SIPP, CEA Cadarache, 13108 St. Paul les Durance (France)], E-mail: sukhhong@nfri.re.kr

    2009-07-15

    In-vessel dusts will be an important issue in next generation fusion devices. They affect not only plasma operations but also safety limits. A new image processing technique for in-vessel dust research is developed in Tore Supra (TS). This paper describes the image processing technique for in-vessel dust study based on simple standard image processing techniques. The technique is intended to use visible standard RGB CCD cameras at a standard frame rate already installed in TS. Studying the traces of straight line-like dust trajectories appearing in the CCD images during the plasma shots, the temporal evolution and the spatial locations of dust creation events (DCEs) can be monitored. Building a database of DCEs, information on the short/long term behavior of in-vessel dusts are obtained. Analyzing the database, statistics on DCEs can be found. Finally, DCEs during 22 ohmic discharges in 2006 CIMES campaign in TS are illustrated as an example.

  16. Three-dimensional temperature field measurement of flame using a single light field camera.

    Science.gov (United States)

    Sun, Jun; Xu, Chuanlong; Zhang, Biao; Hossain, Md Moinul; Wang, Shimin; Qi, Hong; Tan, Heping

    2016-01-25

    Compared with conventional camera, the light field camera takes the advantage of being capable of recording the direction and intensity information of each ray projected onto the CCD (charge couple device) sensor simultaneously. In this paper, a novel method is proposed for reconstructing three-dimensional (3-D) temperature field of a flame based on a single light field camera. A radiative imaging of a single light field camera is also modeled for the flame. In this model, the principal ray represents the beam projected onto the pixel of the CCD sensor. The radiation direction of the ray from the flame outside the camera is obtained according to thin lens equation based on geometrical optics. The intensities of the principal rays recorded by the pixels on the CCD sensor are mathematically modeled based on radiative transfer equation. The temperature distribution of the flame is then reconstructed by solving the mathematical model through the use of least square QR-factorization algorithm (LSQR). The numerical simulations and experiments are carried out to investigate the validity of the proposed method. The results presented in this study show that the proposed method is capable of reconstructing the 3-D temperature field of a flame.

  17. Microcontroller-based intelligent low-cost-linear-sensor-camera for general edge detection

    Science.gov (United States)

    Hussmann, Stephan; Justen, Detlef

    1997-09-01

    With this paper we would like to present an intelligent low- cost-camera. Intelligent means that a microcontroller does all the controlling and provides several in- and outputs. The camera is a stand-alone system. The basic element of the camera is a linear sensor that consists of a photodiode array (PDA). In comparison with standard CCD-chips this type of sensor is a low cost component and its operation is very simple. Furthermore this paper shows the mechanical, electrical and electro-optical differences between CCD- and PDA-sensors. So the reader will be able to choose the right sensor for a particular task. Two cases of industrial applications are listed at the end of this paper.

  18. X-ray framing camera for pulsed, high current, electron beam x-ray sources

    CERN Document Server

    Failor, B H; Riordan, j c; Lojewski, D Y

    2007-01-01

    High power x-ray sources built for nuclear weapons effects testing are evolving toward larger overall diameters and smaller anode cathode gaps. We describe a framing camera developed to measure the time-evolution of these 20-50 ns pulsed x-ray sources produced by currents in the 1.5-2.5 MA range and endpoint voltages between 0.2 and 1.5 MV. The camera has up to 4 frames with 5 ns gate widths; the frames are separated by 5 ns. The image data are recorded electronically with a gated intensified CCD camera and the data are available immediately following a shot. A fast plastic scintillator (2.1 ns decay time) converts the x-rays to visible light and, for high sensitivity, a fiber optic imaging bundle carries the light to the CCD input. Examples of image data are shown.

  19. CCD UBVRI photometry of NGC 6811

    CERN Document Server

    Yontan, T; Bostancı, Z F; Ak, T; Karaali, S; Güver, T; Ak, S; Duran, S; Paunzen, E

    2014-01-01

    We present the results of CCD UBVRI observations of the open cluster NGC 6811 obtained on 18th July 2012 with the 1m telescope at the T\\"UB\\.ITAK National Observatory (TUG). Using these photometric results, we determine the structural and astrophysical parameters of the cluster. The mean photometric uncertainties are better than 0.02 mag in the V magnitude and B-V, V-R, and V-I colour indices to about 0.03 mag for U-B among stars brighter than magnitude V=18. Cluster member stars were separated from the field stars using the Galaxia model of Sharma et al. (2011) together with other techniques. The core radius of the cluster is found to be $r_{c}$=3.60 arcmin. The astrophysical parameters were determined simultaneously via Bayesian statistics using the colour-magnitude diagrams V versus B-V, V versus V-I, V versus V-R, and V versus R-I of the cluster. The resulting most likely parameters were further confirmed using independent methods, removing any possible degeneracies. The colour excess, distance modulus, m...

  20. Super CCD SR是什么

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    我最近看到富士公司新上市的数字相机FinePix S3 Pro的像素为:617万S像素,617万R像素,共1234万像素。请问:什么是S像素,什么是R像素?为什么富士的相机的像素标明S和R像素.而其它品牌的数字相机没有这样标明.富士相机的Super CCD SR传感器与其他品牌数字相机的CCD传感器相比,有什么特点?为什么总像素1234万像素;而有效像素却只有610万像素?另外。数字相机用的CMOS传感器与CCD传感器有什么异同?

  1. 多通道CCD信号模拟器实现方法研究%Research on design method of multichannel CCD signal simulator

    Institute of Scientific and Technical Information of China (English)

    马飞; 刘琦; 尹娜; 万旻

    2012-01-01

    卫星相机视频处理电路CCD芯片在测试过程中容易损坏且价格昂贵,为满足卫星相机视频处理电路的测试需求,研究并设计了一种多通道CCD信号模拟器,能够模拟最多16路线阵或面阵等多种类型的CCD信号.以Xilinx公司XC5V型号FPGA为核心,采用VHDL语言实现CCD信号发生的逻辑设计,利用RS232接口接收上位机指令实现不同种类CCD信号的选择输出.实际应用表明,该模拟器具有很好的通用性和灵活性,能够满足多种卫星相机视频处理电路的测试需求.%CCDs used in video process circuit of satellite cameras are expensive and possible to be damaged while testing. To satisfy the needs for testing video process circuit of satellite cameras,a design is provided to achieve a multichannel CCD signal simulator. Up to 16 CCD signal channels can be generated. An FPGA of Xilinx XC5V was adopted to make a center unit, the logic of CCD signals generating is developed with VHDL. The RS232 interface is used to receive instructions from the host computer, and different types of signals are generated and outputted depending on the instructions. Practical applications show that the CCD simulator is flexible and can work well. The design of the CCD simulator meets the requirements of testing video process circuit in several different types of satellite cameras.

  2. Inner FoV Stitching of Spaceborne TDI CCD Images Based on Sensor Geometry and Projection Plane in Object Space

    Directory of Open Access Journals (Sweden)

    Xinming Tang

    2014-07-01

    Full Text Available High-quality inner FoV (Field of View stitching is currently a prerequisite step for photogrammetric processing and application of image data acquired by spaceborne TDI CCD cameras. After reviewing the technical development in the issue, we present an inner FoV stitching method based on sensor geometry and projection plane in object space, in which the geometric sensor model of spaceborne TDI CCD images is used to establish image point correspondence between the stitched image and the TDI CCD images, using an object-space projection plane as the intermediary. In this study, first, the rigorous geometric sensor model of the TDI CCD images is constructed. Second, principle and implementation of the stitching method are described. Third, panchromatic high-resolution (HR images of ZY-1 02C satellite and triple linear-array images of ZY-3 satellite are utilized to validate the correctness and feasibility of the method. Fourth, the stitching precision and geometric quality of the generated stitched images are evaluated. All the stitched images reached the sub-pixel level in precision. In addition, the geometric models of the stitched images can be constructed with zero loss in geometric precision. Experimental results demonstrate the advantages of the method for having small image distortion when on-orbit geometric calibration of satellite sensors is available. Overall, the new method provide a novel solution for inner FoV stitching of spaceborne TDI CCD images, in which all the sub-images are projected to the object space based on the sensor geometry, performing indirect image geometric rectification along and across the target trajectory. At present, this method has been successfully applied in the daily processing system for ZY-1 02C and ZY-3 satellites.

  3. A New Serial-direction Trail Effect in CCD Images of the Lunar-based Ultraviolet Telescope

    Science.gov (United States)

    Wu, C.; Deng, J. S.; Guyonnet, A.; Antilogus, P.; Cao, L.; Cai, H. B.; Meng, X. M.; Han, X. H.; Qiu, Y. L.; Wang, J.; Wang, S.; Wei, J. Y.; Xin, L. P.; Li, G. W.

    2016-10-01

    Unexpected trails have been seen subsequent to relative bright sources in astronomical images taken with the CCD camera of the Lunar-based Ultraviolet Telescope (LUT) since its first light on the Moon’s surface. The trails can only be found in the serial-direction of CCD readout, differing themselves from image trails of radiation-damaged space-borne CCDs, which usually appear in the parallel-readout direction. After analyzing the same trail defects following warm pixels (WPs) in dark frames, we found that the relative intensity profile of the LUT CCD trails can be expressed as an exponential function of the distance i (in number of pixels) of the trailing pixel to the original source (or WP), i.e., {\\mathtt{\\exp }}(α {\\mathtt{i}}+β ). The parameters α and β seem to be independent of the CCD temperature, intensity of the source (or WP), and its position in the CCD frame. The main trail characteristics show evolution occurring at an increase rate of ˜(7.3 ± 3.6) × 10-4 in the first two operation years. The trails affect the consistency of the profiles of different brightness sources, which make smaller aperture photometry have larger extra systematic error. The astrometric uncertainty caused by the trails is too small to be acceptable based on LUT requirements for astrometry accuracy. Based on the empirical profile model, a correction method has been developed for LUT images that works well for restoring the fluxes of astronomical sources that are lost in trailing pixels.

  4. Camera as Cultural Critique

    DEFF Research Database (Denmark)

    Suhr, Christian

    2015-01-01

    What does the use of cameras entail for the production of cultural critique in anthropology? Visual anthropological analysis and cultural critique starts at the very moment a camera is brought into the field or existing visual images are engaged. The framing, distances, and interactions between...... researchers, cameras, and filmed subjects already inherently comprise analytical decisions. It is these ethnographic qualities inherent in audiovisual and photographic imagery that make it of particular value to a participatory anthropological enterprise that seeks to resist analytic closure and seeks instead...

  5. TARGETLESS CAMERA CALIBRATION

    Directory of Open Access Journals (Sweden)

    L. Barazzetti

    2012-09-01

    Full Text Available In photogrammetry a camera is considered calibrated if its interior orientation parameters are known. These encompass the principal distance, the principal point position and some Additional Parameters used to model possible systematic errors. The current state of the art for automated camera calibration relies on the use of coded targets to accurately determine the image correspondences. This paper presents a new methodology for the efficient and rigorous photogrammetric calibration of digital cameras which does not require any longer the use of targets. A set of images depicting a scene with a good texture are sufficient for the extraction of natural corresponding image points. These are automatically matched with feature-based approaches and robust estimation techniques. The successive photogrammetric bundle adjustment retrieves the unknown camera parameters and their theoretical accuracies. Examples, considerations and comparisons with real data and different case studies are illustrated to show the potentialities of the proposed methodology.

  6. The MKID Camera

    Science.gov (United States)

    Maloney, P. R.; Czakon, N. G.; Day, P. K.; Duan, R.; Gao, J.; Glenn, J.; Golwala, S.; Hollister, M.; LeDuc, H. G.; Mazin, B.; Noroozian, O.; Nguyen, H. T.; Sayers, J.; Schlaerth, J.; Vaillancourt, J. E.; Vayonakis, A.; Wilson, P.; Zmuidzinas, J.

    2009-12-01

    The MKID Camera project is a collaborative effort of Caltech, JPL, the University of Colorado, and UC Santa Barbara to develop a large-format, multi-color millimeter and submillimeter-wavelength camera for astronomy using microwave kinetic inductance detectors (MKIDs). These are superconducting, micro-resonators fabricated from thin aluminum and niobium films. We couple the MKIDs to multi-slot antennas and measure the change in surface impedance produced by photon-induced breaking of Cooper pairs. The readout is almost entirely at room temperature and can be highly multiplexed; in principle hundreds or even thousands of resonators could be read out on a single feedline. The camera will have 576 spatial pixels that image simultaneously in four bands at 750, 850, 1100 and 1300 microns. It is scheduled for deployment at the Caltech Submillimeter Observatory in the summer of 2010. We present an overview of the camera design and readout and describe the current status of testing and fabrication.

  7. Target Image Matching Algorithm Based on Binocular CCD Ranging

    Directory of Open Access Journals (Sweden)

    Dongming Li

    2014-01-01

    Full Text Available This paper proposed target image in a subpixel level matching algorithm for binocular CCD ranging, which is based on the principle of binocular CCD ranging. In the paper, firstly, we introduced the ranging principle of the binocular ranging system and deduced a binocular parallax formula. Secondly, we deduced the algorithm which was named improved cross-correlation matching algorithm and cubic surface fitting algorithm for target images matched, and it could achieve a subpixel level matching for binocular CCD ranging images. Lastly, through experiment we have analyzed and verified the actual CCD ranging images, then analyzed the errors of the experimental results and corrected the formula of calculating system errors. Experimental results showed that the actual measurement accuracy of a target within 3 km was higher than 0.52%, which meet the accuracy requirements of the high precision binocular ranging.

  8. Atmospheric correction of CBERS CCD images with MODIS data

    Institute of Scientific and Technical Information of China (English)

    LI Junsheng; ZHANG Bing; CHEN Zhengchao; SHEN Qian

    2006-01-01

    China Brazil Earth Resource Satellite (CBERS) CCD images have much potential for inland water environmental monitoring. However, their atmospheric accuracy correction can affect their quantitative applications. This paper contains an atmospheric correction algorithm for CBERS CCD images with MODIS data from the same day, the use of which improves the atmospheric correction algorithm of ocean color remote sensing developed by Gordon (1993, 1994) and makes it applicable to inland waters. The improved algorithm retrieves atmospheric parameters from MODIS data and uses them to perform the atmospheric correction of CBERS CCD images. Experimental results show that the atmospheric correction algorithm of CBERS CCD images assisted by MODIS data is reliable. Furthermore, MODIS data can be freely obtained on a daily basis, making the algorithm developed in this paper useful for environmental monitoring of inland waters.

  9. CCD image data acquisition system for optical astronomy.

    Science.gov (United States)

    Bhat, P. N.; Patnaik, K.; Kembhavi, A. K.; Patnaik, A. R.; Prabhu, T. P.

    1990-11-01

    A complete image processing system based on a charge coupled device (CCD) has been developed at TIFR, Bombay, for use in optical astronomy. The system consists of a P-8600/B GEC CCD chip, a CCD controller, a VAX 11/725 mini-computer to carry out the image acquisition and display on a VS-11 monitor. All the necessary software and part of the hardware were developed locally, integrated together and installed at the Vainu Bappu Observatory at Kavalur. CCD as an imaging device and its advantages over the conventional photographic plate is briefly reviewed. The acquisition system is described in detail. The preliminary results are presented and the future research programme is outlined.

  10. Photon counting imaging and centroiding with an electron-bombarded CCD using single molecule localisation software

    Science.gov (United States)

    Hirvonen, Liisa M.; Barber, Matthew J.; Suhling, Klaus

    2016-06-01

    Photon event centroiding in photon counting imaging and single-molecule localisation in super-resolution fluorescence microscopy share many traits. Although photon event centroiding has traditionally been performed with simple single-iteration algorithms, we recently reported that iterative fitting algorithms originally developed for single-molecule localisation fluorescence microscopy work very well when applied to centroiding photon events imaged with an MCP-intensified CMOS camera. Here, we have applied these algorithms for centroiding of photon events from an electron-bombarded CCD (EBCCD). We find that centroiding algorithms based on iterative fitting of the photon events yield excellent results and allow fitting of overlapping photon events, a feature not reported before and an important aspect to facilitate an increased count rate and shorter acquisition times.

  11. White light interferometer with color CCD for 3D-surface profiling of microsystems

    Science.gov (United States)

    Upputuri, Paul K.; Pramanik, Manojit; Nandigana, Krishna M.; Kothiyal, Mahendra P.

    2015-03-01

    White light interferometry (WLI) is a state-of-the-art technique for high resolution full-filed 3-D surface profiling of Microsystems. However, the WLI is rather slow, because the number of frames to be recorded and evaluated is large compared to the single wavelength phase shifting interferometry. In this paper, we combine white light interferometer with a single-chip color CCD camera which makes the measurement faster, simpler, and cost-effective. The red-bluegreen (RGB) color interferogram stored in a computer is then decomposed into its individual components and corresponding phase maps for red, green, and blue components are calculated independently. The usefulness of the technique is demonstrated on reflective micro-scale-samples.

  12. Imaging the Moon II: Webcam CCD observations & analysis (a two week lab for non-majors)

    CERN Document Server

    Sato, Takashi

    2013-01-01

    Presented is a successful two week lab involving real sky observations of the Moon in which students make telescopic observations and analyze their own images. Originally developed around the 35 mm film camera as a common household object adapted for astronomical work, the lab transitioned to use the webcam as film photography evolved into an obscure specialty technology and increasing numbers of students had little familiarity with it. The printed circuit board with the CCD is harvested from a retail webcam and affixed to a tube to mount on a telescope in place of an eyepiece. Image frames are compiled to form a lunar mosaic and crater sizes are measured. Students also work through the logistical steps of telescope time assignment and scheduling, keeping to schedule and working with uncertainties of weather, in ways paralleling research observations. Because there is no need for a campus observatory, this lab can be replicated at a wide variety of institutions.

  13. Gamma camera system

    International Nuclear Information System (INIS)

    A detailed description is given of a novel gamma camera which is designed to produce superior images than conventional cameras used in nuclear medicine. The detector consists of a solid state detector (e.g. germanium) which is formed to have a plurality of discrete components to enable 2-dimensional position identification. Details of the electronic processing circuits are given and the problems and limitations introduced by noise are discussed in full. (U.K.)

  14. Application of CCD measurement technique for wear on pantograph sliding plates

    Science.gov (United States)

    Yang, Kai; Wang, Li; Gao, Xiaorong; Zhao, Quanke; Wang, Zeyong; Peng, Chaoyong

    2009-05-01

    Pantograph sliding plate is the most important electricity-collecting part in locomotive power supply system. Once the sliding plates are disabled, they will be severe dangerous for safety. The measurement for pantograph of 27.5KV is especially difficult. The article uses non-contact and online dynamic detection by utilizing CCD technique to solve the problem. The system will get all images of sliding plates after triggering by space arrangement of CCD cameras cooperated with flashlights. The precision of demarcate is guaranteed by special methods. It adopts directional edge search to get sliding plates, and connect the images of different CCDS. It also makes use of conditional Hough transformation to locate the wire. The wear on sliding plates will be given after complicated processing. The system is applicable to the detection for all kinds of pantographs by adding different arithmetic amends. At last the precision can achieve +/-0.5mm . At the same time a database is setup which can give the trend curve of wear, it can predict the limit time of the sliding plates.

  15. A new method of CCD dark current correction via extracting the dark information from scientific images

    CERN Document Server

    Ma, Bin; Hu, Yi; Liu, Qiang; Wang, Lifan; Wei, Peng

    2014-01-01

    We have developed a new method to correct dark current at relatively high temperatures for Charge-Coupled Device (CCD) images when dark frames cannot be obtained on the telescope. For images taken with the Antarctic Survey Telescopes (AST3) in 2012, due to the low cooling efficiency, the median CCD temperature was -46$^\\circ$C, resulting in a high dark current level of about 3$e^-$/pix/sec, even comparable to the sky brightness (10$e^-$/pix/sec). If not corrected, the nonuniformity of the dark current could even overweight the photon noise of the sky background. However, dark frames could not be obtained during the observing season because the camera was operated in frame-transfer mode without a shutter, and the telescope was unattended in winter. Here we present an alternative, but simple and effective method to derive the dark current frame from the scientific images. Then we can scale this dark frame to the temperature at which the scientific images were taken, and apply the dark frame corrections to the s...

  16. Development of photoelectric balanced car based on the linear CCD sensor

    Directory of Open Access Journals (Sweden)

    Wang Feng

    2016-01-01

    Full Text Available The smart car is designed based on Freescale’s MC9S12XS128 and a linear CCD camera. The linear CCD collects the road information and sends it to MCU through the operational amplifier. The PID control algorithm, the proportional–integral–derivative control algorithm, is adopted synthetically to control the smart car. First, the smart car’s inclination and angular velocity are detect through the accelerometers and gyro sensors, then the PD control algorithm, the proportional–derivative control algorithm, is employed to make the smart car have the ability of two-wheeled self-balancing. Second, the speed of wheel obtained by the encoder is fed back to the MCU by way of pulse signal, then the PI control algorithm, the proportional–integral control algorithm, is employed to make the speed of smart car reach the set point in the shortest possible time and stabilize at the set point. Finally, the PD control algorithm is used to regulate the smart car’s turning angle to make the smart car respond quickly while the smart car is passing the curve path. The smart car can realize the self-balancing control of two wheels and track automatically the black and while lines to march.

  17. First observations from a CCD all-sky spectrograph at Barentsburg (Spitsbergen

    Directory of Open Access Journals (Sweden)

    S. A. Chernouss

    2008-05-01

    Full Text Available A digital CCD all-sky spectrograph was made by the Polar Geophysical Institute (PGI to support IPY activity in auroral research. The device was tested at the Barentsburg observatory of PGI during the winter season of 2005–2006. The spectrograph is based on a cooled CCD and a transmission grating. The main features of this spectrograph are: a wide field of view (~180°, a wide spectral range (380–740 nm, a spectral resolution of 0.6 nm, a background level of about 100 R at 1-min exposure time. Several thousand spectra of nightglow and aurora were recorded during the observation season. It was possible to register both the strong auroral emissions, as well as weak ones. Spectra of aurora, including nitrogen and oxygen molecular and atomic emissions, as well as OH emissions of the nightglow are shown. A comparison has been conducted of auroral spectra obtained by the film all-sky spectral camera C-180-S at Spitsbergen during IGY, with spectra obtained at Barentsburg during the last winter season. The relationship between the red (630.0 nm and green (557.7 nm auroral emissions shows that the green emission is dominant near the minimum of the solar cycle activity (2005–2006. The opposite situation is observed during 1958–1959, with a maximum solar cycle activity.

  18. Design of Frame-transferred Surface Array CCD Imaging System for Dark Objects

    Science.gov (United States)

    Zhang, Yu-heng; Yan, Yi-hua

    2016-01-01

    In order to realize the requirement of low-noise observations of dark objects in deep-space explorations, the design method for a simple and stable space camera imaging system is proposed in this paper. Based on the back-illuminated frame-transferred surface array CCD (CCD47-20AIMO) produced by the British E2V company, the circuitry design is given for the every part of the system. In which the applications of the correlated double-sampling analog-digital converter (AD) and the synchronous dynamic random access memory (SDRAM) can effectively suppress the correlated noise in the image signal. In addition, a drive control method favorable to the adjustment of exposure time is proposed, in the light-sensing stage it provides the exposure time with an independent and adjustable time delay to make the imaging system satisfy the requirement of long exposure time setting. The imaging system adopts the Cyclone III-series EP3C25Q240C8 field programable gate array produced by the Altera company as the kernel control device, and the drives are programmed in modules according to the function of the every device, in favor of transplantation. The simulative and experimental results indicate that the drive circuitry works normally, and that the system design can satisfy the preset requirement.

  19. Segment Based Camera Calibration

    Institute of Scientific and Technical Information of China (English)

    马颂德; 魏国庆; 等

    1993-01-01

    The basic idea of calibrating a camera system in previous approaches is to determine camera parmeters by using a set of known 3D points as calibration reference.In this paper,we present a method of camera calibration in whih camera parameters are determined by a set of 3D lines.A set of constraints is derived on camea parameters in terms of perspective line mapping.Form these constraints,the same perspective transformation matrix as that for point mapping can be computed linearly.The minimum number of calibration lines is 6.This result generalizes that of Liu,Huang and Faugeras[12] for camera location determination in which at least 8 line correspondences are required for linear computation of camera location.Since line segments in an image can be located easily and more accurately than points,the use of lines as calibration reference tends to ease the computation in inage preprocessing and to improve calibration accuracy.Experimental results on the calibration along with stereo reconstruction are reported.

  20. Spacecraft camera image registration

    Science.gov (United States)

    Kamel, Ahmed A. (Inventor); Graul, Donald W. (Inventor); Chan, Fred N. T. (Inventor); Gamble, Donald W. (Inventor)

    1987-01-01

    A system for achieving spacecraft camera (1, 2) image registration comprises a portion external to the spacecraft and an image motion compensation system (IMCS) portion onboard the spacecraft. Within the IMCS, a computer (38) calculates an image registration compensation signal (60) which is sent to the scan control loops (84, 88, 94, 98) of the onboard cameras (1, 2). At the location external to the spacecraft, the long-term orbital and attitude perturbations on the spacecraft are modeled. Coefficients (K, A) from this model are periodically sent to the onboard computer (38) by means of a command unit (39). The coefficients (K, A) take into account observations of stars and landmarks made by the spacecraft cameras (1, 2) themselves. The computer (38) takes as inputs the updated coefficients (K, A) plus synchronization information indicating the mirror position (AZ, EL) of each of the spacecraft cameras (1, 2), operating mode, and starting and stopping status of the scan lines generated by these cameras (1, 2), and generates in response thereto the image registration compensation signal (60). The sources of periodic thermal errors on the spacecraft are discussed. The system is checked by calculating measurement residuals, the difference between the landmark and star locations predicted at the external location and the landmark and star locations as measured by the spacecraft cameras (1, 2).

  1. In-process automatic wavelength calibration for CCD-spectrometers

    OpenAIRE

    Mirapeix Serrano, Jesús María; Cobo García, Adolfo; Cubillas de Cos, Ana María; Conde Portilla, Olga María; López Higuera, José Miguel

    2008-01-01

    In CCD-spectrometers, the relation between the CCD-pixel number and the associated wavelength is established by means of a calibration polynomial, whose coefficients are typically obtained using a calibration lamp with known emission line wavelengths and a regression procedure. A recalculation of this polynomial has to be performed periodically, as the pixel number versus wavelength relation can change with ambient temperature variations or modifications in the optics attached to the spectrom...

  2. Medical x-ray-sensitive array based on CCD

    Science.gov (United States)

    Gnedenko, Valeri G.; Krasnjuk, Andrey A.; Larionov, Sergei V.; Phainberg, Evgeni M.; Shilin, Victor A.; Skrylev, Alexander S.; Stenin, Vladimir J.

    1996-04-01

    The achievements of CCD technology allow to design X-ray sensitive solid-state images for various medicine applications. The first medical systems have been created for using in dental practice and diagnosis. This radiovisiographic method allows to reduce X-ray exposure by 80%, except any films and provide paralleled diagnosis capacities which revolutionize every day practice. In the future a mosaic scanner with CCD chips will be used for detecting breast cancer.

  3. SIMULTANEOUS RECORDING OF FRINGE PATTERNS WITH ONE CAMERA

    Institute of Scientific and Technical Information of China (English)

    SU Fei; DAI Fulong; CHIAN Kerm Sin; YI Sung

    2004-01-01

    A novel method to separate and simultaneously record the Moiré interferometry fringe patterns of three deformation fields with only one CCD camera is developed; details of its operation principle, key points and error analysis are presented. With this technique, the deformation in U, V and W fields can be measured simultaneously, so dynamic test with comprehensive information can be performed. The advantage of this technique over other similar techniques lies in its simplicity, easy implementation and low cost. An application of this technique is given to show its feasibility. Technical problems that may be caused with this technique are also analyzed.

  4. Development of SED Camera for Quasars in Early Universe (SQUEAN)

    CERN Document Server

    Kim, Sanghyuk; Lee, Hye-In; Park, Woojin; Ji, Tae-Geun; Hyun, Minhee; Choi, Changsu; Im, Myungshin; Pak, Soojong

    2016-01-01

    We describe the characteristics and performance of a camera system, Spectral energy distribution Camera for Quasars in Early Universe (SQUEAN). It was developed to measure SEDs of high redshift quasar candidates (z $\\gtrsim$ 5) and other targets, e.g., young stellar objects, supernovae, and gamma-ray bursts, and to trace the time variability of SEDs of objects such as active galactic nuclei (AGNs). SQUEAN consists of an on-axis focal plane camera module, an auto-guiding system, and mechanical supporting structures. The science camera module is composed of a focal reducer, a customizable filter wheel, and a CCD camera on the focal plane. The filter wheel uses filter cartridges that can house filters with different shapes and sizes, enabling the filter wheel to hold twenty filters of 50 mm $\\times$ 50 mm size, ten filters of 86 mm $\\times$ 86 mm size, or many other combinations. The initial filter mask was applied to calibrate the filter wheel with high accuracy and we verified that the filter position is repea...

  5. Development of SED Camera for Quasars in Early Universe (SQUEAN)

    Science.gov (United States)

    Kim, Sanghyuk; Jeon, Yiseul; Lee, Hye-In; Park, Woojin; Ji, Tae-Geun; Hyun, Minhee; Choi, Changsu; Im, Myungshin; Pak, Soojong

    2016-11-01

    We describe the characteristics and performance of a camera system, Spectral energy distribution Camera for Quasars in Early Universe (SQUEAN). It was developed to measure SEDs of high-redshift quasar candidates (z ≳ 5) and other targets, e.g., young stellar objects, supernovae, and gamma-ray bursts, and to trace the time variability of SEDs of objects such as active galactic nuclei (AGNs). SQUEAN consists of an on-axis focal plane camera module, an autoguiding system, and mechanical supporting structures. The science camera module is composed of a focal reducer, a customizable filter wheel, and a CCD camera on the focal plane. The filter wheel uses filter cartridges that can house filters with different shapes and sizes, enabling the filter wheel to hold 20 filters of 50 mm × 50 mm size, 10 filters of 86 mm × 86 mm size, or many other combinations. The initial filter mask was applied to calibrate the filter wheel with high accuracy, and we verified that the filter position is repeatable at much less than one pixel accuracy. We installed and tested 50 nm medium bandwidth filters of 600–1050 nm and other filters at the commissioning observation in 2015 February. We found that SQUEAN can reach limiting magnitudes of 23.3–25.3 AB mag at 5σ in a one-hour total integration time.

  6. Electronic Image Readout Devices Used In Conjunction With Picosecond Streak Cameras

    Science.gov (United States)

    Cavailler, C.; Genoud, M.; Fleurot, N.; Launspach, J.; Mazataud, D.; Mens, A.

    1985-02-01

    Understanding the laser-matter interaction experiments require a dynamic recording of the phenomena as well as a good knowledge of the laser pulse occuring during the irradiation of the target ; those measurements are made with streak cameras the increasing number of which leads to processing problems when the results are recorded on films. Furthermore, since physicists wish to have those temporal information immediatly, we unfolded automatic image readout devices fitted specially to streak cameras. The first one used an ISOCON tube operating with a slow sweep (0.5 s frame)1-2. The sensitivity of the tube was very good but its dynamic range was too limited when seeing pulsed images at low light level. So we developped two electronic readout chains with solid state devices which behave better for that kind of light. The first one was designed to get the most information along the temporal axis of the camera sweep (1024 points) in one or two spatial channels ; this device operates a linear 1024 photodiodes array the signal of which is digitized on 12 bits. We have obtained a temporal resolution better than 15 ps and a dynamic range over 500 ; this system is mainly useful to study laser pulses (rise time, temporal profile...)3. For applications requiring two dimension images, we studied and realized a device operating a CCD array and a fiber optics reducer (40-18 mm) adapting the image of the streak camera screen to the dimensions of the input fiber optics of the CCD. A comparison has been made on different CCD cameras on a test setup which simulates the experimental conditions, in order to choose the CCD which would fit the best for that purpose ; we present these results here, as well as those of the associated readout chains.

  7. CAOS-CMOS camera.

    Science.gov (United States)

    Riza, Nabeel A; La Torre, Juan Pablo; Amin, M Junaid

    2016-06-13

    Proposed and experimentally demonstrated is the CAOS-CMOS camera design that combines the coded access optical sensor (CAOS) imager platform with the CMOS multi-pixel optical sensor. The unique CAOS-CMOS camera engages the classic CMOS sensor light staring mode with the time-frequency-space agile pixel CAOS imager mode within one programmable optical unit to realize a high dynamic range imager for extreme light contrast conditions. The experimentally demonstrated CAOS-CMOS camera is built using a digital micromirror device, a silicon point-photo-detector with a variable gain amplifier, and a silicon CMOS sensor with a maximum rated 51.3 dB dynamic range. White light imaging of three different brightness simultaneously viewed targets, that is not possible by the CMOS sensor, is achieved by the CAOS-CMOS camera demonstrating an 82.06 dB dynamic range. Applications for the camera include industrial machine vision, welding, laser analysis, automotive, night vision, surveillance and multispectral military systems. PMID:27410361

  8. CAOS-CMOS camera.

    Science.gov (United States)

    Riza, Nabeel A; La Torre, Juan Pablo; Amin, M Junaid

    2016-06-13

    Proposed and experimentally demonstrated is the CAOS-CMOS camera design that combines the coded access optical sensor (CAOS) imager platform with the CMOS multi-pixel optical sensor. The unique CAOS-CMOS camera engages the classic CMOS sensor light staring mode with the time-frequency-space agile pixel CAOS imager mode within one programmable optical unit to realize a high dynamic range imager for extreme light contrast conditions. The experimentally demonstrated CAOS-CMOS camera is built using a digital micromirror device, a silicon point-photo-detector with a variable gain amplifier, and a silicon CMOS sensor with a maximum rated 51.3 dB dynamic range. White light imaging of three different brightness simultaneously viewed targets, that is not possible by the CMOS sensor, is achieved by the CAOS-CMOS camera demonstrating an 82.06 dB dynamic range. Applications for the camera include industrial machine vision, welding, laser analysis, automotive, night vision, surveillance and multispectral military systems.

  9. HIGH SPEED CAMERA

    Science.gov (United States)

    Rogers, B.T. Jr.; Davis, W.C.

    1957-12-17

    This patent relates to high speed cameras having resolution times of less than one-tenth microseconds suitable for filming distinct sequences of a very fast event such as an explosion. This camera consists of a rotating mirror with reflecting surfaces on both sides, a narrow mirror acting as a slit in a focal plane shutter, various other mirror and lens systems as well as an innage recording surface. The combination of the rotating mirrors and the slit mirror causes discrete, narrow, separate pictures to fall upon the film plane, thereby forming a moving image increment of the photographed event. Placing a reflecting surface on each side of the rotating mirror cancels the image velocity that one side of the rotating mirror would impart, so as a camera having this short a resolution time is thereby possible.

  10. Status of the Dark Energy Survey Camera (DECam) project

    Science.gov (United States)

    Flaugher, Brenna L.; Abbott, Timothy M. C.; Angstadt, Robert; Annis, Jim; Antonik, Michelle L.; Bailey, Jim; Ballester, Otger; Bernstein, Joseph P.; Bernstein, Rebecca A.; Bonati, Marco; Bremer, Gale; Briones, Jorge; Brooks, David; Buckley-Geer, Elizabeth J.; Campa, Juila; Cardiel-Sas, Laia; Castander, Francisco; Castilla, Javier; Cease, Herman; Chappa, Steve; Chi, Edward C.; da Costa, Luis; DePoy, Darren L.; Derylo, Gregory; de Vincente, Juan; Diehl, H. Thomas; Doel, Peter; Estrada, Juan; Eiting, Jacob; Elliott, Anne E.; Finley, David A.; Flores, Rolando; Frieman, Josh; Gaztanaga, Enrique; Gerdes, David; Gladders, Mike; Guarino, V.; Gutierrez, G.; Grudzinski, Jim; Hanlon, Bill; Hao, Jiangang; Holland, Steve; Honscheid, Klaus; Huffman, Dave; Jackson, Cheryl; Jonas, Michelle; Karliner, Inga; Kau, Daekwang; Kent, Steve; Kozlovsky, Mark; Krempetz, Kurt; Krider, John; Kubik, Donna; Kuehn, Kyler; Kuhlmann, Steve E.; Kuk, Kevin; Lahav, Ofer; Langellier, Nick; Lathrop, Andrew; Lewis, Peter M.; Lin, Huan; Lorenzon, Wolfgang; Martinez, Gustavo; McKay, Timothy; Merritt, Wyatt; Meyer, Mark; Miquel, Ramon; Morgan, Jim; Moore, Peter; Moore, Todd; Neilsen, Eric; Nord, Brian; Ogando, Ricardo; Olson, Jamieson; Patton, Kenneth; Peoples, John; Plazas, Andres; Qian, Tao; Roe, Natalie; Roodman, Aaron; Rossetto, B.; Sanchez, E.; Soares-Santos, Marcelle; Scarpine, Vic; Schalk, Terry; Schindler, Rafe; Schmidt, Ricardo; Schmitt, Richard; Schubnell, Mike; Schultz, Kenneth; Selen, M.; Serrano, Santiago; Shaw, Terri; Simaitis, Vaidas; Slaughter, Jean; Smith, R. Christopher; Spinka, Hal; Stefanik, Andy; Stuermer, Walter; Sypniewski, Adam; Talaga, R.; Tarle, Greg; Thaler, Jon; Tucker, Doug; Walker, Alistair R.; Weaverdyck, Curtis; Wester, William; Woods, Robert J.; Worswick, Sue; Zhao, Allen

    2012-09-01

    The Dark Energy Survey Collaboration has completed construction of the Dark Energy Camera (DECam), a 3 square degree, 570 Megapixel CCD camera which will be mounted on the Blanco 4-meter telescope at CTIO. DECam will be used to perform the 5000 sq. deg. Dark Energy Survey with 30% of the telescope time over a 5 year period. During the remainder of the time, and after the survey, DECam will be available as a community instrument. All components of DECam have been shipped to Chile and post-shipping checkout finished in Jan. 2012. Installation is in progress. A summary of lessons learned and an update of the performance of DECam and the status of the DECam installation and commissioning will be presented.

  11. Artificial human vision camera

    Science.gov (United States)

    Goudou, J.-F.; Maggio, S.; Fagno, M.

    2014-10-01

    In this paper we present a real-time vision system modeling the human vision system. Our purpose is to inspire from human vision bio-mechanics to improve robotic capabilities for tasks such as objects detection and tracking. This work describes first the bio-mechanical discrepancies between human vision and classic cameras and the retinal processing stage that takes place in the eye, before the optic nerve. The second part describes our implementation of these principles on a 3-camera optical, mechanical and software model of the human eyes and associated bio-inspired attention model.

  12. The Star Formation Camera

    OpenAIRE

    Scowen, Paul A.; Jansen, Rolf; Beasley, Matthew; Calzetti, Daniela; Desch, Steven; Fullerton, Alex; Gallagher, John; Lisman, Doug; Macenka, Steve; Malhotra, Sangeeta; McCaughrean, Mark; Nikzad, Shouleh; O'Connell, Robert; Oey, Sally; Padgett, Deborah

    2009-01-01

    The Star Formation Camera (SFC) is a wide-field (~15'x19, >280 arcmin^2), high-resolution (18x18 mas pixels) UV/optical dichroic camera designed for the Theia 4-m space-borne space telescope concept. SFC will deliver diffraction-limited images at lambda > 300 nm in both a blue (190-517nm) and a red (517-1075nm) channel simultaneously. Our aim is to conduct a comprehensive and systematic study of the astrophysical processes and environments relevant for the births and life cycles of stars and ...

  13. Automatic Camera Control

    DEFF Research Database (Denmark)

    Burelli, Paolo; Preuss, Mike

    2014-01-01

    Automatically generating computer animations is a challenging and complex problem with applications in games and film production. In this paper, we investigate howto translate a shot list for a virtual scene into a series of virtual camera configurations — i.e automatically controlling the virtual...... camera. We approach this problem by modelling it as a dynamic multi-objective optimisation problem and show how this metaphor allows a much richer expressiveness than a classical single objective approach. Finally, we showcase the application of a multi-objective evolutionary algorithm to generate a shot...

  14. Underwater camera with depth measurement

    Science.gov (United States)

    Wang, Wei-Chih; Lin, Keng-Ren; Tsui, Chi L.; Schipf, David; Leang, Jonathan

    2016-04-01

    The objective of this study is to develop an RGB-D (video + depth) camera that provides three-dimensional image data for use in the haptic feedback of a robotic underwater ordnance recovery system. Two camera systems were developed and studied. The first depth camera relies on structured light (as used by the Microsoft Kinect), where the displacement of an object is determined by variations of the geometry of a projected pattern. The other camera system is based on a Time of Flight (ToF) depth camera. The results of the structural light camera system shows that the camera system requires a stronger light source with a similar operating wavelength and bandwidth to achieve a desirable working distance in water. This approach might not be robust enough for our proposed underwater RGB-D camera system, as it will require a complete re-design of the light source component. The ToF camera system instead, allows an arbitrary placement of light source and camera. The intensity output of the broadband LED light source in the ToF camera system can be increased by putting them into an array configuration and the LEDs can be modulated comfortably with any waveform and frequencies required by the ToF camera. In this paper, both camera were evaluated and experiments were conducted to demonstrate the versatility of the ToF camera.

  15. Communities, Cameras, and Conservation

    Science.gov (United States)

    Patterson, Barbara

    2012-01-01

    Communities, Cameras, and Conservation (CCC) is the most exciting and valuable program the author has seen in her 30 years of teaching field science courses. In this citizen science project, students and community volunteers collect data on mountain lions ("Puma concolor") at four natural areas and public parks along the Front Range of Colorado.…

  16. Advanced Virgo phase cameras

    Science.gov (United States)

    van der Schaaf, L.; Agatsuma, K.; van Beuzekom, M.; Gebyehu, M.; van den Brand, J.

    2016-05-01

    A century after the prediction of gravitational waves, detectors have reached the sensitivity needed to proof their existence. One of them, the Virgo interferometer in Pisa, is presently being upgraded to Advanced Virgo (AdV) and will come into operation in 2016. The power stored in the interferometer arms raises from 20 to 700 kW. This increase is expected to introduce higher order modes in the beam, which could reduce the circulating power in the interferometer, limiting the sensitivity of the instrument. To suppress these higher-order modes, the core optics of Advanced Virgo is equipped with a thermal compensation system. Phase cameras, monitoring the real-time status of the beam constitute a critical component of this compensation system. These cameras measure the phases and amplitudes of the laser-light fields at the frequencies selected to control the interferometer. The measurement combines heterodyne detection with a scan of the wave front over a photodetector with pin-hole aperture. Three cameras observe the phase front of these laser sidebands. Two of them monitor the in-and output of the interferometer arms and the third one is used in the control of the aberrations introduced by the power recycling cavity. In this paper the working principle of the phase cameras is explained and some characteristic parameters are described.

  17. The world's fastest camera

    CERN Multimedia

    Piquepaille, Roland

    2006-01-01

    This image processor is not your typical digital camera. It took 6 years to 20 people and $6 million to build the "Regional Calorimeter Trigger"(RCT) which will be a component of the Compact Muon Solenoid (CMS) experiment, one of the detectors on the Large Hadron Collider (LHC) in Geneva, Switzerland (1 page)

  18. Make a Pinhole Camera

    Science.gov (United States)

    Fisher, Diane K.; Novati, Alexander

    2009-01-01

    On Earth, using ordinary visible light, one can create a single image of light recorded over time. Of course a movie or video is light recorded over time, but it is a series of instantaneous snapshots, rather than light and time both recorded on the same medium. A pinhole camera, which is simple to make out of ordinary materials and using ordinary…

  19. Computer-aided analysis of CCD linear image sensors

    Science.gov (United States)

    Prince, S. S.

    1976-01-01

    Special test equipment and techniques to collect and process image information from charge coupled devices (CCDs) by digital computer were reviewed. The video channel was traced from the CCD to the direct memory access bus of the Interdata Computer. Software was developed to evaluate and characterize a CCD for (1) dark signal versus temperature relationship, (2) calculation of temporal noise magnitude and noise shape for each pixel, (3) spatial noise into the video chain due to dark signal, (4) response versus illumination relationship (gamma), (5) response versus wavelength of illumination (spectral), (6) optimization of forcing functions, and (7) evaluation of an image viewed by a CCD. The basic software differences and specific examples of each program operating on real data are presented.

  20. The research on calibration methods of dual-CCD laser three-dimensional human face scanning system

    Science.gov (United States)

    Wang, Jinjiang; Chang, Tianyu; Ge, Baozhen; Tian, Qingguo; Yang, Fengting; Shi, Shendong

    2013-09-01

    In this paper, on the basis of considering the performance advantages of two-step method, we combines the stereo matching of binocular stereo vision with active laser scanning to calibrate the system. Above all, we select a reference camera coordinate system as the world coordinate system and unity the coordinates of two CCD cameras. And then obtain the new perspective projection matrix (PPM) of each camera after the epipolar rectification. By those, the corresponding epipolar equation of two cameras can be defined. So by utilizing the trigonometric parallax method, we can measure the space point position after distortion correction and achieve stereo matching calibration between two image points. Experiments verify that this method can improve accuracy and system stability is guaranteed. The stereo matching calibration has a simple process with low-cost, and simplifies regular maintenance work. It can acquire 3D coordinates only by planar checkerboard calibration without the need of designing specific standard target or using electronic theodolite. It is found that during the experiment two-step calibration error and lens distortion lead to the stratification of point cloud data. The proposed calibration method which combining active line laser scanning and binocular stereo vision has the both advantages of them. It has more flexible applicability. Theory analysis and experiment shows the method is reasonable.

  1. Validation of spectral sky radiance derived from all-sky camera images – a case study

    Directory of Open Access Journals (Sweden)

    K. Tohsing

    2014-01-01

    Full Text Available Spectral sky radiance (380–760 nm is derived from measurements with a Hemispherical Sky Imager (HSI system. The HSI consists of a commercial compact CCD (charge coupled device camera equipped with a fish-eye lens and provides hemispherical sky images in three reference bands such as red, green and blue. To obtain the spectral sky radiance from these images non-linear regression functions for various sky conditions have been derived. The camera-based spectral sky radiance was validated by spectral sky radiance measured with a CCD spectroradiometer. The spectral sky radiance for complete distribution over the hemisphere between both instruments deviates by less than 20% at 500 nm for all sky conditions and for zenith angles less than 80°. The reconstructed spectra of the wavelength 380 nm to 760 nm between both instruments at various directions deviate by less then 20% for all sky conditions.

  2. Validation of spectral sky radiance derived from all-sky camera images – a case study

    Directory of Open Access Journals (Sweden)

    K. Tohsing

    2014-07-01

    Full Text Available Spectral sky radiance (380–760 nm is derived from measurements with a hemispherical sky imager (HSI system. The HSI consists of a commercial compact CCD (charge coupled device camera equipped with a fish-eye lens and provides hemispherical sky images in three reference bands such as red, green and blue. To obtain the spectral sky radiance from these images, non-linear regression functions for various sky conditions have been derived. The camera-based spectral sky radiance was validated using spectral sky radiance measured with a CCD spectroradiometer. The spectral sky radiance for complete distribution over the hemisphere between both instruments deviates by less than 20% at 500 nm for all sky conditions and for zenith angles less than 80°. The reconstructed spectra of the wavelengths 380–760 nm between both instruments at various directions deviate by less than 20% for all sky conditions.

  3. CCD sensors in synchrotron X-ray detectors

    Science.gov (United States)

    Strauss, M. G.; Naday, I.; Sherman, I. S.; Kraimer, M. R.; Westbrook, E. M.; Zaluzec, N. J.

    1988-04-01

    The intense photon flux from advanced synchrotron light sources, such as the 7-GeV synchrotron being designed at Argonne, require integrating-type detectors. Charge-coupled devices (CCDs) are well suited as synchrotron X-ray detectors. When irradiated indirectly via a phosphor followed by reducing optics, diffraction patterns of 100 cm 2 can be imaged on a 2 cm 2 CCD. With a conversion efficiency of ˜ 1 CCD electron/X-ray photon, a peak saturation capacity of > 10 6 X-rays can be obtained. A programmable CCD controller operating at a clock frequency of 20 MHz has been developed. The readout rate is 5 × 10 6 pixels/s and the shift rate in the parallel registers is 10 6 lines/s. The test detector was evaluated in two experiments. In protein crystallography diffraction patterns have been obtained from a lysozyme crystal using a conventional rotating anode X-ray generator. Based on these results we expect to obtain at a synchrotron diffraction images at a rate of ˜ 1 frame/s or a complete 3-dimensional data set from a single crystal in ˜ 2 min. In electron energy-loss spectroscopy (EELS), the CCD was used in a parallel detection mode which is similar to the mode array detectors are used in dispersive EXAFS. With a beam current corresponding to 3 × 10 9 electron/s on the detector, a series of 64 spectra were recorded on the CCD in a continuous sequence without interruption due to readout. The frame-to-frame pixel signal fluctuations had σ = 0.4% from which DQE = 0.4 was obtained, where the detector conversion efficiency was 2.6 CCD electrons/X-ray photon. These multiple frame series also showed the time-resolved modulation of the electron microscope optics by stray magnetic fields.

  4. Controlling the Swift XRT CCD temperature via passive cooling

    Science.gov (United States)

    Kennea, Jamie A.; Burrows, D. N.; Wells, A.; Pagani, C.; Hill, J. E.; Racusin, J. L.; Morris, D.; Hunsberger, S.; Abbey, A. F.; Beardmore, A.; Campana, S.; Chester, M.; Chincarini, G.; Cusumano, G.; Gehrels, N.; Godet, O.; Mineo, T.; La Parola, V.; Mangano, V.; Moretti, A.; Nousek, J.; Osborne, J.; Page, K.; Perri, M.; Tagliaferri, G.; Tamburelli, F.

    2005-08-01

    The Swift X-ray Telescope (XRT) is a CCD based X-ray telescope designed for localization, spectroscopy and long term light curve monitoring of Gamma-Ray Bursts and their X-ray afterglows. Shortly after launch there was a failure of the thermo-electric cooler on the XRT CCD. Due to this the Swift XRT Team had the unexpected challenge of ensuring that the CCD temperature stayed below -50C utilizing only passive cooling through a radiator mounted on the side of the Swift. Here we show that the temperature of the XRT CCD is correlated with the average elevation of the Earth above the XRT radiator, which is in turn related to the targets that Swift observes in an orbit. In order to maximize passive cooling of the XRT CCD, the XRT team devised several novel methods for ensuring that the XRT radiator's exposure to the Earth was minimized to ensure efficient cooling. These methods include: picking targets on the sky for Swift to point at which are known to put the spacecraft into a good orientation for maximizing XRT cooling; biasing the spacecraft roll angle to point the XRT radiator away from the Earth as much as possible; utilizing time in the SAA, in which all of the instruments on-board Swift are non-operational, to point at "cold targets" and restricting observing time on "warm" targets to only the periods at which the spacecraft is in a favorable orientation for cooling. By doing this at the observation planning stage we have been able to minimize the heating of the CCD and maintain the XRT as a fully operational scientific instrument, without compromising the science goals of the Swift mission.

  5. Image Sensors Enhance Camera Technologies

    Science.gov (United States)

    2010-01-01

    In the 1990s, a Jet Propulsion Laboratory team led by Eric Fossum researched ways of improving complementary metal-oxide semiconductor (CMOS) image sensors in order to miniaturize cameras on spacecraft while maintaining scientific image quality. Fossum s team founded a company to commercialize the resulting CMOS active pixel sensor. Now called the Aptina Imaging Corporation, based in San Jose, California, the company has shipped over 1 billion sensors for use in applications such as digital cameras, camera phones, Web cameras, and automotive cameras. Today, one of every three cell phone cameras on the planet feature Aptina s sensor technology.

  6. The Magellan Adaptive Secondary VisAO Camera: Diffraction- Limited Broadband Visible Imaging and 20mas Fiber Array IFS

    OpenAIRE

    Kopon, Derek; Close, Laird M; Males, Jared R.; Gasho, Victor; Follette, Katherine

    2010-01-01

    The Magellan Adaptive Secondary AO system, scheduled for first light in the fall of 2011, will be able to simultaneously perform diffraction limited AO science in both the mid-IR, using the BLINC/MIRAC4 10\\{mu}m camera, and in the visible using our novel VisAO camera. The VisAO camera will be able to operate as either an imager, using a CCD47 with 8.5 mas pixels, or as an IFS, using a custom fiber array at the focal plane with 20 mas elements in its highest resolution mode. In imaging mode, t...

  7. MISR radiometric camera-by-camera Cloud Mask V004

    Data.gov (United States)

    National Aeronautics and Space Administration — This file contains the Radiometric camera-by-camera Cloud Mask dataset. It is used to determine whether a scene is classified as clear or cloudy. A new parameter...

  8. 2048 pixel front illuminated linear CCD for spectroscopy

    Science.gov (United States)

    Wang, Chao-min; Liu, Chang-ju; Zheng, Yu; Li, Ping

    2009-07-01

    The charge couple device(CCD) used in spectroscopy requests good response to the wave bands between 190-1000 nm. The common measure to carry out UV response is phosphor coatings or back illuminated. Among them, phosphors are wavelength converters that convert short-wavelength light into the visible spectral region. This technology needs adding special process which not only raises cost, reduces yield, but also reduces the resolution of the image. Back illuminated is reducing CCD thickness to 15um which is thinner than the normal paper by mechanical polishing and chemical corrosion after completing the front processes of CCD. This technology needs special instrument, complex process , and the yield is also low. Both phosphor coatings and back illuminated have some disadvantages such as low space resolution, complex process, low yield, high cost etc. The CCD of traditional structure has no response to the wavelength less than 350nm, the reason is that the length of UV penetrating through Si is shallow, the penetrating length is only 6.5nm of 300nm UV, the shorter wavelength UV, the shallower penetrating length. The junction depth of normal CCD process is above 200nm, some realize shallow junction through molecular beam epitaxy, but the instrument is expensive and the cost is high. The photosensitive area of normal structure CCD adopting portrait P-N junction, light incidences from N area, N area can't be completely depleted because of the restrict of physics, photon can't arrive depletion area directly. On the basis of thorough analysis traditional UV CCD, horizontal P-N junction structure of Photosensitive area is put forward, whose depletion can reach the surface, the photon falls depletion area directly, which can effectively carry out the absorption of the UV light and the collection of photoelectron. As the latent absorption of Si3N4 to UV with less than 248nm wavelength, the Si3N4 passivation on the photosensitive area is take out. The improved 2048 elements

  9. An introduction to some imperfections of CCD sensors

    International Nuclear Information System (INIS)

    CCD sensors do not deliver a perfect image of the light they receive. Beyond the well known linear image smearing due to diffusion of charges during their drift towards the pixel wells, non-linear effects are at play in these sensors. We now have ample evidence for both a flux-dependent and static image distortions, especially but not only, on deep-depleted CCDs. For large surveys relying on CCD sensors, these effects should now be taken into account when reducing data. We present here a summary of current results on sensor characterization and mitigation methods

  10. An introduction to some imperfections of CCD sensors

    OpenAIRE

    Astier, Pierre

    2015-01-01

    CCD sensors do not deliver a perfect image of the light they receive. Beyond the well known linear image smearing due to diffusion of charges during their drift towards the pixel wells, non-linear effects are at play in these sensors. We now have ample evidence for both a flux- dependent and static image distortions, especially but not only, on deep-depleted CCDs. For large surveys relying on CCD sensors, these effects should now be taken into account when reducing data. We present here a sum...

  11. GAMPIX: A new generation of gamma camera

    Science.gov (United States)

    Gmar, M.; Agelou, M.; Carrel, F.; Schoepff, V.

    2011-10-01

    Gamma imaging is a technique of great interest in several fields such as homeland security or decommissioning/dismantling of nuclear facilities in order to localize hot spots of radioactivity. In the nineties, previous works led by CEA LIST resulted in the development of a first generation of gamma camera called CARTOGAM, now commercialized by AREVA CANBERRA. Even if its performances can be adapted to many applications, its weight of 15 kg can be an issue. For several years, CEA LIST has been developing a new generation of gamma camera, called GAMPIX. This system is mainly based on the Medipix2 chip, hybridized to a 1 mm thick CdTe substrate. A coded mask replaces the pinhole collimator in order to increase the sensitivity of the gamma camera. Hence, we obtained a very compact device (global weight less than 1 kg without any shielding), which is easy to handle and to use. In this article, we present the main characteristics of GAMPIX and we expose the first experimental results illustrating the performances of this new generation of gamma camera.

  12. On the absolute calibration of SO2 cameras

    OpenAIRE

    Lübcke, P.; N. Bobrowski; Illing, S.; Kern, C.; J. M. Alvarez Nieves; Vogel, L.; J. Zielcke; H. Delgado Granados; U. Platt

    2013-01-01

    Sulphur dioxide emission rate measurements are an important tool for volcanic monitoring and eruption risk assessment. The SO2 camera technique remotely measures volcanic emissions by analysing the ultraviolet absorption of SO2 in a narrow spectral window between 300 and 320 nm using solar radiation scattered in the atmosphere. The SO2 absorption is selectively detected by mounting band-pass interference filters in front of a two-dimensional, UV-sensitive CCD detector. One important step for ...

  13. Camera-based stereo laser-tracking system for robot-positioning applications

    Science.gov (United States)

    Allen, Charles R.; Mistry, Nilesh

    1993-08-01

    This paper describes the theory behind laser tracking measurement systems (LTMS) and the development of a prototype LTMS system at Newcastle. An assessment is made of the accuracy of positioning achieved by the system in the control of the end-effector position of a Puma 560 robot manipulator using a CCD camera positioning sensor and a hollow cube retro- reflector placed on the robot wrist.

  14. The LSST Camera 500 watt -130 degC Mixed Refrigerant Cooling System

    Energy Technology Data Exchange (ETDEWEB)

    Bowden, Gordon B.; Langton, Brian J.; /SLAC; Little, William A.; /MMR-Technologies, Mountain View, CA; Powers, Jacob R; Schindler, Rafe H.; /SLAC; Spektor, Sam; /MMR-Technologies, Mountain View, CA

    2014-05-28

    The LSST Camera has a higher cryogenic heat load than previous CCD telescope cameras due to its large size (634 mm diameter focal plane, 3.2 Giga pixels) and its close coupled front-end electronics operating at low temperature inside the cryostat. Various refrigeration technologies are considered for this telescope/camera environment. MMR-Technology’s Mixed Refrigerant technology was chosen. A collaboration with that company was started in 2009. The system, based on a cluster of Joule-Thomson refrigerators running a special blend of mixed refrigerants is described. Both the advantages and problems of applying this technology to telescope camera refrigeration are discussed. Test results from a prototype refrigerator running in a realistic telescope configuration are reported. Current and future stages of the development program are described. (auth)

  15. The LSST camera 500-watt -130°C mixed refrigerant cooling system

    Science.gov (United States)

    Bowden, Gordon B.; Langton, Brian J.; Little, William A.; Powers, Jacob R.; Schindler, Rafe H.; Spektor, Sam

    2014-07-01

    The LSST Camera has a higher cryogenic heat load than previous CCD telescope cameras due to its large size (634 mm diameter focal plane, 3.2 Giga pixels) and its close coupled front-end electronics operating at low temperature inside the cryostat. Various refrigeration technologies are considered for this telescope/camera environment. MMR-Technology's Mixed Refrigerant technology was chosen. A collaboration with that company was started in 2009. The system, based on a cluster of Joule-Thomson refrigerators running a special blend of mixed refrigerants is described. Both the advantages and problems of applying this technology to telescope camera refrigeration are discussed. Test results from a prototype refrigerator running in a realistic telescope configuration are reported. Current and future stages of the development program are described.

  16. The LSST Camera 500 watt -130 degC Mixed Refrigerant Cooling System

    International Nuclear Information System (INIS)

    The LSST Camera has a higher cryogenic heat load than previous CCD telescope cameras due to its large size (634 mm diameter focal plane, 3.2 Giga pixels) and its close coupled front-end electronics operating at low temperature inside the cryostat. Various refrigeration technologies are considered for this telescope/camera environment. MMR-Technology's Mixed Refrigerant technology was chosen. A collaboration with that company was started in 2009. The system, based on a cluster of Joule-Thomson refrigerators running a special blend of mixed refrigerants is described. Both the advantages and problems of applying this technology to telescope camera refrigeration are discussed. Test results from a prototype refrigerator running in a realistic telescope configuration are reported. Current and future stages of the development program are described. (auth)

  17. LLiST - a new star tracker camera for tip-tilt correction at IOTA

    OpenAIRE

    Schuller, P.A.; Lacasse, M. G.; Lydon, D.; McGonagle, W. H.; Pedretti, E; Reich, R. K.; Schloerb, F. P.; Traub, W. A.

    2004-01-01

    The tip-tilt correction system at the Infrared Optical Telescope Array (IOTA) has been upgraded with a new star tracker camera. The camera features a backside-illuminated CCD chip offering doubled overall quantum efficiency and a four times higher system gain compared to the previous system. Tests carried out to characterize the new system showed a higher system gain with a lower read-out noise electron level. Shorter read-out cycle times now allow to compensate tip-tilt fluctuations so that ...

  18. LLiST - a new star tracker camera for tip-tilt correction at IOTA

    CERN Document Server

    Schuller, P A; Lydon, D; McGonagle, W H; Pedretti, E; Reich, R K; Schloerb, F P; Traub, W A

    2004-01-01

    The tip-tilt correction system at the Infrared Optical Telescope Array (IOTA) has been upgraded with a new star tracker camera. The camera features a backside-illuminated CCD chip offering doubled overall quantum efficiency and a four times higher system gain compared to the previous system. Tests carried out to characterize the new system showed a higher system gain with a lower read-out noise electron level. Shorter read-out cycle times now allow to compensate tip-tilt fluctuations so that their error imposed on visibility measurements becomes comparable to, and even smaller than, that of higher-order aberrations.

  19. Positioning of Screw Holes Group Based on Digital Camera and Digital Control Drilling

    Institute of Scientific and Technical Information of China (English)

    FENG Wenhao; LI Jiansong; YAN Li; SU Guozhong; YUAN Xiuxiao; ZHONG Shengzhang; JI Huiming

    2004-01-01

    Positioning of screw holes is an important production procedure for steel construction connecting with bolts. In this paper, a new production method is presented, in which the digital camera is used for taking pictures of screw holes and other techniques are advanced. This paper also indicates that the pixels of CCD chip in photogrammetry should be chosen as all geometric units in an image, such as interior elements and all kinds of distortions. The measure can also simplify the camera calibration for determining the size of non-square pixel.

  20. Correction of rolling wheel images captured by a linear array camera.

    Science.gov (United States)

    Xu, Jiayuan; Sun, Ran; Tian, Yupeng; Xie, Qi; Yang, Ying; Liu, Hongdan; Cao, Lei

    2015-11-20

    As a critical part of the train, wheels affect railway transport security to a large extent. This paper introduces an online method to detect the wheel tread of a train. The wheel tread images are collected by industrial linear array charge coupled device (CCD) cameras when the train is moving at a low velocity. This study defines the positioning of the cameras and determines how to select other parameters such as the horizontal angle and the scanning range. The deformation of the wheel tread image can be calculated based on these parameters and corrected by gray interpolation. PMID:26836530

  1. General Attitude Control Algorithm for Spacecraft Equipped with Star Camera and Reaction Wheels

    DEFF Research Database (Denmark)

    Wisniewski, Rafal; Kulczycki, P.

    A configuration consisting of a star camera, four reaction wheels and magnetorquers for momentum unloading has become standard for many spacecraft missions. This popularity has motivated numerous agencies and private companies to initiate work on the design of an imbedded attitude control system...... realized on an integrated circuit. This paper considers two issues: slew maneuver with a feature of avoiding direct exposure of the camera's CCD chip to the Sun %, three-axis attitude control and optimal control torque distribution in a reaction wheel assembly. The attitude controller is synthesized...

  2. A Simple Approach to Collecting Useful Wildlife Data Using Remote Camera-Traps in Undergraduate Biology Courses

    Science.gov (United States)

    Christensen, David R.

    2016-01-01

    Remote camera-traps are commonly used to estimate the abundance, diversity, behavior and habitat use of wildlife in an inexpensive and nonintrusive manner. Because of the increasing use of remote-cameras in wildlife studies, students interested in wildlife biology should be exposed to the use of remote-cameras early in their academic careers.…

  3. Development of an n-channel CCD, CCD-NeXT1, for Soft X-ray Imager onboard the NeXT satellite

    CERN Document Server

    Takagi, Shin-ichiro; Inui, Tatsuya; Matsumoto, Hironori; Koyama, Katsuji; Ozawa, Hideki; Tohiguchi, Masakuni; Matsuura, Daisuke; Miyata, Emi; Tsunemi, Hiroshi; Miyaguchi, Kazuhisa; Maeda, Kentaro; Kohno, Hirohiko

    2007-01-01

    NeXT (New X-ray Telescope) is the next Japanese X-ray astronomical satellite mission after the Suzaku satellite. NeXT aims to perform wide band imaging spectroscopy. Due to the successful development of a multilayer coated mirror, called a supermirror, NeXT can focus X-rays in the energy range from 0.1 keV up to 80 keV. To cover this wide energy range, we are in the process of developing a hybrid X-ray camera, Wideband X-ray Imager (WXI) as a focal plane detector of the supermirror. The WXI consists of X-ray CCDs (SXI) and CdTe pixelized detectors (HXI), which cover the lower and higher X-ray energy bands of 0.1-80 keV, respectively. The X-ray CCDs of the SXI are stacked above the CdTe pixelized detectors of the HXI. The X-ray CCDs of the SXI detect soft X-rays below $\\sim$ 10 keV and allow hard X-rays pass into the CdTe detectors of the HXI without loss. Thus, we have been developing a "back-supportless CCD" with a thick depletion layer, a thinned silicon wafer, and a back-supportless structure. In this pape...

  4. A four-lens based plenoptic camera for depth measurements

    Science.gov (United States)

    Riou, Cécile; Deng, Zhiyuan; Colicchio, Bruno; Lauffenburger, Jean-Philippe; Kohler, Sophie; Haeberlé, Olivier; Cudel, Christophe

    2015-04-01

    In previous works, we have extended the principles of "variable homography", defined by Zhang and Greenspan, for measuring height of emergent fibers on glass and non-woven fabrics. This method has been defined for working with fabric samples progressing on a conveyor belt. Triggered acquisition of two successive images was needed to perform the 3D measurement. In this work, we have retained advantages of homography variable for measurements along Z axis, but we have reduced acquisitions number to a single one, by developing an acquisition device characterized by 4 lenses placed in front of a single image sensor. The idea is then to obtain four projected sub-images on a single CCD sensor. The device becomes a plenoptic or light field camera, capturing multiple views on the same image sensor. We have adapted the variable homography formulation for this device and we propose a new formulation to calculate a depth with plenoptic cameras. With these results, we have transformed our plenoptic camera in a depth camera and first results given are very promising.

  5. Panoramic camera systems for meteor tracking and meteorite recovery

    Science.gov (United States)

    Brosch, N.; Nemiroff, R.; Shamir, L.

    2006-08-01

    Since 1969, the Antarctic became the most fertile part of the Earth to yield meteorites. The recovered meteorites have been concentrated in specific locations by the actions of wind and snow. It is difficult, therefore to derive their history prior to their arrival onto the Antarctic ice except for an estimate of their space residence. We propose to deploy a system of two or more panoramic cameras in the Antarctic designed to observe meteors and measure their space trajectories. The cameras are patterned after the successful CONCAM systems with the specific difference that each would be equipped with a high-precision light chopper. The CCD images collected by the continuously-operating cameras will yield the angular speed of each detected meteor. Using two or more cameras spaced by a few km or tens of km it will be possible, using triangulation, to derive the space trajectories of these meteors. In case of meteorite-dropping meteors, the trajectory analysis will allow the determination of the approximate ground impact. This would allow recovery of the meteorite(s) in the subsequent Antarctic spring season with the full knowledge of the space history and with a very small chance of weathering.

  6. Dual cameras acquisition and display system of retina-like sensor camera and rectangular sensor camera

    Science.gov (United States)

    Cao, Nan; Cao, Fengmei; Lin, Yabin; Bai, Tingzhu; Song, Shengyu

    2015-04-01

    For a new kind of retina-like senor camera and a traditional rectangular sensor camera, dual cameras acquisition and display system need to be built. We introduce the principle and the development of retina-like senor. Image coordinates transformation and interpolation based on sub-pixel interpolation need to be realized for our retina-like sensor's special pixels distribution. The hardware platform is composed of retina-like senor camera, rectangular sensor camera, image grabber and PC. Combined the MIL and OpenCV library, the software program is composed in VC++ on VS 2010. Experience results show that the system can realizes two cameras' acquisition and display.

  7. Volumetric particle image velocimetry with a single plenoptic camera

    Science.gov (United States)

    Fahringer, Timothy W.; Lynch, Kyle P.; Thurow, Brian S.

    2015-11-01

    A novel three-dimensional (3D), three-component (3C) particle image velocimetry (PIV) technique based on volume illumination and light field imaging with a single plenoptic camera is described. A plenoptic camera uses a densely packed microlens array mounted near a high resolution image sensor to sample the spatial and angular distribution of light collected by the camera. The multiplicative algebraic reconstruction technique (MART) computed tomography algorithm is used to reconstruct a volumetric intensity field from individual snapshots and a cross-correlation algorithm is used to estimate the velocity field from a pair of reconstructed particle volumes. This work provides an introduction to the basic concepts of light field imaging with a plenoptic camera and describes the unique implementation of MART in the context of plenoptic image data for 3D/3C PIV measurements. Simulations of a plenoptic camera using geometric optics are used to generate synthetic plenoptic particle images, which are subsequently used to estimate the quality of particle volume reconstructions at various particle number densities. 3D reconstructions using this method produce reconstructed particles that are elongated by a factor of approximately 4 along the optical axis of the camera. A simulated 3D Gaussian vortex is used to test the capability of single camera plenoptic PIV to produce a 3D/3C vector field, where it was found that lateral displacements could be measured to approximately 0.2 voxel accuracy in the lateral direction and 1 voxel in the depth direction over a 300× 200× 200 voxel volume. The feasibility of the technique is demonstrated experimentally using a home-built plenoptic camera based on a 16-megapixel interline CCD camera and a 289× 193 array of microlenses and a pulsed Nd:YAG laser. 3D/3C measurements were performed in the wake of a low Reynolds number circular cylinder and compared with measurements made using a conventional 2D/2C PIV system. Overall, single camera

  8. Accuracy Potential and Applications of MIDAS Aerial Oblique Camera System

    Science.gov (United States)

    Madani, M.

    2012-07-01

    Airborne oblique cameras such as Fairchild T-3A were initially used for military reconnaissance in 30s. A modern professional digital oblique camera such as MIDAS (Multi-camera Integrated Digital Acquisition System) is used to generate lifelike three dimensional to the users for visualizations, GIS applications, architectural modeling, city modeling, games, simulators, etc. Oblique imagery provide the best vantage for accessing and reviewing changes to the local government tax base, property valuation assessment, buying & selling of residential/commercial for better decisions in a more timely manner. Oblique imagery is also used for infrastructure monitoring making sure safe operations of transportation, utilities, and facilities. Sanborn Mapping Company acquired one MIDAS from TrackAir in 2011. This system consists of four tilted (45 degrees) cameras and one vertical camera connected to a dedicated data acquisition computer system. The 5 digital cameras are based on the Canon EOS 1DS Mark3 with Zeiss lenses. The CCD size is 5,616 by 3,744 (21 MPixels) with the pixel size of 6.4 microns. Multiple flights using different camera configurations (nadir/oblique (28 mm/50 mm) and (50 mm/50 mm)) were flown over downtown Colorado Springs, Colorado. Boresight fights for 28 mm nadir camera were flown at 600 m and 1,200 m and for 50 mm nadir camera at 750 m and 1500 m. Cameras were calibrated by using a 3D cage and multiple convergent images utilizing Australis model. In this paper, the MIDAS system is described, a number of real data sets collected during the aforementioned flights are presented together with their associated flight configurations, data processing workflow, system calibration and quality control workflows are highlighted and the achievable accuracy is presented in some detail. This study revealed that the expected accuracy of about 1 to 1.5 GSD (Ground Sample Distance) for planimetry and about 2 to 2.5 GSD for vertical can be achieved. Remaining systematic

  9. Combustion pinhole camera system

    Science.gov (United States)

    Witte, Arvel B.

    1984-02-21

    A pinhole camera system utilizing a sealed optical-purge assembly which provides optical access into a coal combustor or other energy conversion reactors. The camera system basically consists of a focused-purge pinhole optical port assembly, a conventional TV vidicon receiver, an external, variable density light filter which is coupled electronically to the vidicon automatic gain control (agc). The key component of this system is the focused-purge pinhole optical port assembly which utilizes a purging inert gas to keep debris from entering the port and a lens arrangement which transfers the pinhole to the outside of the port assembly. One additional feature of the port assembly is that it is not flush with the interior of the combustor.

  10. Camera Surveillance Quadrotor

    OpenAIRE

    Hjelm, Emil; Yousif, Robert

    2015-01-01

    A quadrotor is a helicopter with four rotors placed at equal distance from the crafts centre of gravity, controlled by letting the different rotors generate different amount of thrust. It uses various sensors to stay stable in the air, correct readings from these sensors are therefore critical. By reducing vibrations, electromagnetic interference and external disturbances the quadrotor’s stability can increase. The purpose of this project is to analyse the feasibility of a quadrotor camera su...

  11. Research on high accuracy diameter measurement system with CCD

    Science.gov (United States)

    Su, Bo; Duan, Guoteng

    2011-08-01

    Non-touch measurement is an important technology in many domains such as the monitoring of tool breakage and tool wear, et al. Based on the method of curve fitting and demanding inflection point, we present a high accuracy non-touch diameter measurement system. The measurement system comprise linear array CCD, CCD driving circuit, power supply, workseat, light source, data acquisition card and so on. The picture element of the linear array CCD is 2048, and the size of every pixel and the spacing of adjacent pixels have the same size of 14μmx14μm. The stabilized voltage supply has a constant voltage output of 3V. The light is generated by a halogen tungsten lamp, which does not represent any risk to the health of the whole system. The data acquisition card converts the analog signal to digital signal with the accuracy of 12 bit. The error of non-uniform of the CCD pixels in sensitivity and the electrical noise error are indicated in detail. The measurement system has a simple structure, high measuring precision, and can be carried out automatically. Experiment proves that the diameter measurement of the system is within the range of Φ0.5~Φ10mm, and the total measuring unstability of the system is within the range of +/- 1.4μm.

  12. CCD photometry of the Globular Cluster NGC 6093

    CERN Document Server

    Ruelas-Mayorga, A; Bernal-Herrera, C A; Nigoche-Netro, A; Echevarria, J; Garcia, A M

    2016-01-01

    In this paper we present photometric CCD observations of the globular cluster NGC 6093 (M80) in filters B, V , R and I. We produce the colour-magnitude diagrams for this object and obtain values for its metallicity [Fe/H], reddening E(V-B), E(V-I) and distance modulus (m - M)_0.

  13. SCREEN photometric property detection system based on area CCD

    Science.gov (United States)

    Yan, Fu-cai; Ye, Wei; Xu, Yu; Wang, Chao; Zhang, Yu-wei

    2011-08-01

    The photometric property detection of screen display is crucial for screen display quality test. Traditional photometry detection technologies were based on photoelectric sensors such as silicon photocell, photo-electric multiplier and CdS, which can detect only some isolated points. To break the limitation of randomness, incompleteness and detection accuracy in current technologies, we designed a screen photometric detection system based on area CCD. The system consists of photometric image sensor, photometric image acquisition hardware and photometric image analyzing software. The photometric image sensor, which adopts optical lens, optical filters and area CCD, adapts its spectrum response property to fit the spectrum luminous efficiency curve V (λ) by adjusting the thickness and quantity of appropriate optical filters. photometric image acquisition hardware adopts the DSP as a core processor to drive the area CCD, to sample, acquire , process and save the image from image sensor, to transmit the image to computer. For real-time performance of transmitting, the hardware system adopts the transmission protocol of USB2.0. The uploaded image will be processed by photometric image analyzing software, and then displayed in real time with detection results. The screen photometric detection technology based on area CCD can detect specifications of the whole screen such as luminance, contrast, onoff ratio and uniformity, breaks the limitation of randomness and incompleteness in current detection technology, exactly and fully reflects the integrated display quality of the whole screen. According to the test results, the accuracy of this system has reached the accuracy level one in China.

  14. Diagnostics of the CCD using the mesh experiment

    CERN Document Server

    Tsunemi, H; Mori, K; Yoshita, K; Miyata, E

    1999-01-01

    We present here the results of a mesh experiment with which we can measure the shape of a charge cloud generated by the photoabsorption of X-rays inside a charge-coupled device (CCD). The mesh used is made of gold of 13-mu m thickness, and has many holes of 1.4 mu m diameter spaced 48 mu m apart. The CCD used has 12 mu m square pixels. A new criterion with which we can determine the precise alignment in the experiment is introduced to eliminate uncertainties. We measured the charge cloud size at three X-ray energies: Al-K (1.5 keV), Mo-L (2.3 keV) and Ti-K (4.5 keV). The shapes can be well represented not by a point-symmetric Gaussian function, but by an axial symmetric Gaussian function with sigma of 0.7-1.5 mu m. The charge cloud size depends weakly on the mean absorption length in silicon. We find that the charge cloud size can be well explained by a simple model inside the CCD. We discuss that the knowledge of the charge cloud size will enable us to improve the position resolution of the CCD.

  15. Low Noise Design of Multi-channel Scanning CCD%多通道扫描CCD相机的低噪声设计

    Institute of Scientific and Technical Information of China (English)

    王颖; 李金; 刘昌举

    2009-01-01

    According to the characteristics of CCD imaging circuit and the analysis of Signal Integrality (SI) and Power integrality (PI) in high-speed circuit,based on 16×8 linear scanning CCD sensors,designed is a multi-channel scanning CCD camera with low noise and high dynamic range.Test results show that the RMS noise of CCD output signal decreases to 0.25 mV.And the signal-noise ratio (SNR) reaches 1 000 : 1 when the amplitude of saturation signal is 80%.%根据CCD戍像电路的特点并结合高速电路信号完整性(SI)和电源完整性(PI)的分析方法,基于16×8线阵CCD器件,设计出具有低噪声、高动态范围的多通道扫描CCD相机.经实际测试,CCD输出信号的均方根噪声降到了0.25mV以下,在饱和信号幅度80%的条件下,信噪比达到了1000:1.

  16. Combining HJ CCD, GF-1 WFV and MODIS Data to Generate Daily High Spatial Resolution Synthetic Data for Environmental Process Monitoring.

    Science.gov (United States)

    Wu, Mingquan; Huang, Wenjiang; Niu, Zheng; Wang, Changyao

    2015-08-01

    The limitations of satellite data acquisition mean that there is a lack of satellite data with high spatial and temporal resolutions for environmental process monitoring. In this study, we address this problem by applying the Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model (ESTARFM) and the Spatial and Temporal Data Fusion Approach (STDFA) to combine Huanjing satellite charge coupled device (HJ CCD), Gaofen satellite no. 1 wide field of view camera (GF-1 WFV) and Moderate Resolution Imaging Spectroradiometer (MODIS) data to generate daily high spatial resolution synthetic data for land surface process monitoring. Actual HJ CCD and GF-1 WFV data were used to evaluate the precision of the synthetic images using the correlation analysis method. Our method was tested and validated for two study areas in Xinjiang Province, China. The results show that both the ESTARFM and STDFA can be applied to combine HJ CCD and MODIS reflectance data, and GF-1 WFV and MODIS reflectance data, to generate synthetic HJ CCD data and synthetic GF-1 WFV data that closely match actual data with correlation coefficients (r) greater than 0.8989 and 0.8643, respectively. Synthetic red- and near infrared (NIR)-band data generated by ESTARFM are more suitable for the calculation of Normalized Different Vegetation Index (NDVI) than the data generated by STDFA. PMID:26308017

  17. The Star Formation Camera

    CERN Document Server

    Scowen, Paul A; Beasley, Matthew; Calzetti, Daniela; Desch, Steven; Fullerton, Alex; Gallagher, John; Lisman, Doug; Macenka, Steve; Malhotra, Sangeeta; McCaughrean, Mark; Nikzad, Shouleh; O'Connell, Robert; Oey, Sally; Padgett, Deborah; Rhoads, James; Roberge, Aki; Siegmund, Oswald; Shaklan, Stuart; Smith, Nathan; Stern, Daniel; Tumlinson, Jason; Windhorst, Rogier; Woodruff, Robert

    2009-01-01

    The Star Formation Camera (SFC) is a wide-field (~15'x19, >280 arcmin^2), high-resolution (18x18 mas pixels) UV/optical dichroic camera designed for the Theia 4-m space-borne space telescope concept. SFC will deliver diffraction-limited images at lambda > 300 nm in both a blue (190-517nm) and a red (517-1075nm) channel simultaneously. Our aim is to conduct a comprehensive and systematic study of the astrophysical processes and environments relevant for the births and life cycles of stars and their planetary systems, and to investigate and understand the range of environments, feedback mechanisms, and other factors that most affect the outcome of the star and planet formation process. This program addresses the origins and evolution of stars, galaxies, and cosmic structure and has direct relevance for the formation and survival of planetary systems like our Solar System and planets like Earth. We present the design and performance specifications resulting from the implementation study of the camera, conducted ...

  18. Gamma ray camera

    Science.gov (United States)

    Perez-Mendez, Victor

    1997-01-01

    A gamma ray camera for detecting rays emanating from a radiation source such as an isotope. The gamma ray camera includes a sensor array formed of a visible light crystal for converting incident gamma rays to a plurality of corresponding visible light photons, and a photosensor array responsive to the visible light photons in order to form an electronic image of the radiation therefrom. The photosensor array is adapted to record an integrated amount of charge proportional to the incident gamma rays closest to it, and includes a transparent metallic layer, photodiode consisting of a p-i-n structure formed on one side of the transparent metallic layer, and comprising an upper p-type layer, an intermediate layer and a lower n-type layer. In the preferred mode, the scintillator crystal is composed essentially of a cesium iodide (CsI) crystal preferably doped with a predetermined amount impurity, and the p-type upper intermediate layers and said n-type layer are essentially composed of hydrogenated amorphous silicon (a-Si:H). The gamma ray camera further includes a collimator interposed between the radiation source and the sensor array, and a readout circuit formed on one side of the photosensor array.

  19. Visibility of microcalcifications in CCD-based cone beam CT: a preliminary study

    Science.gov (United States)

    Shen, Youtao; Chen, Lingyun; Ge, Shuaiping; Yi, Ying; Han, Tao; Zhong, Yuncheng; Lai, Chao-Jen; Liu, Xinming; Wang, Tianpeng; Shaw, Chris C.

    2009-02-01

    In this work, we investigated the visibility of microcalcifications in CCD-based cone beam CT (CBCT) breast imaging. A paraffin cylinder with a diameter of 135 mm and a thickness of 40 mm was used to simulate a 100% adipose breast. Calcium carbonate grains, ranging from 140-150 to 200-212 μm in size, were used to simulate the microcalcifications. Groups of 25 same size microcalcifications were arranged into 5 × 5 clusters. Each cluster was embedded at the center of a smaller (15 mm diameter) cylindrical paraffin phantom, which were inserted into a hole at the center of the breast phantom. The breast phantom with the simulated microcalcifications was scanned on a bench top experimental CCDbased cone beam CT system at various exposure levels with two CCD cameras: Hamamatsu's C4742-56-12ER and Dalsa 99-66-0000-00. 300 projection images were acquired over 360° and reconstructed with Feldkamp's backprojection algorithm using a ramp filter. The images were reviewed by 6 readers independently. The ratios of visible microcalcifications were recorded and averaged over all readers. These ratios were plotted as the function of measured image signal-to-noise ratio (SNR) for various scans. It was found that 94% visibility was achieved for 200-212 μm calcifications at an SNR of 48.2 while 50% visibility was achieved for 200-212, 180-200, 160-180, 150-160 and 140-150 μm calcifications at an SNR of 25.0, 35.3, 38.2, 42.2 and 64.4, respectively.

  20. Reducing Scattered Light in CCD Images at the CTIO 0.9m Telescope

    Science.gov (United States)

    Barnaby, D.; Rauscher, B. J.

    1998-12-01

    We have been studying luminous halos around spiral galaxies in very deep near-infrared K-band images (limiting surface brightness =24 mag arcsec(-2) ; lambda_ {c} = 2.35 mu m). Following our successful detection of a halo around the southern spiral galaxy ESO 240-G11 (Rauscher et al. 1998), we collected optical CCD images of candidate galaxies at the Cerro Tololo Interamerican Observatory (CTIO) 0.9 m telescope from 17-21 Sept 1998. Because light scattered by the telescope can mask or mimic faint, extended emission, we took precautions to minimize stray and scattered light. To assess the amount of scattered light, we collected images of the telescope pupil using a pinhole camera, which we constructed by laying a sheet of aluminum foil, perforated with a submillimeter hole, 19 mm in front of the CCD. These images showed that the telescope did scatter light on the order of a few percent over a radius of about 2 arcminutes. Supressing this extraneous light was highly desirable, since halo surface brightness can be baffles. One baffle consisted of a 0.95 m diameter tube added as an extension to the telescope, which has a closed-tube design. The other 2 baffles were diaphragms mounted between the primary baffle (the ``chimney'') and the shutter. These baffles effectively eliminated the largest sources of scattered light, which appear to be the edge of the secondary baffle and the inner surface of the chimney (Figure 1, http:// astro.uchicago.edu/home/web/barnaby/sctrdlite98.html). In this paper, we quantify the reduction in scattered light and examine the most useful location to add baffles to this telescope. Acknowledgements. We thank the CTIO Telescope Operations staff for their help in constructing and installing the baffles. We also thank support astronomer Nick Suntzeff for suggesting the pinhole tests. Rauscher, B. J. et al. 1998, ApJ, 506, 116

  1. Programmable CCD imaging system for synchrotron radiation studies

    International Nuclear Information System (INIS)

    A real-time imaging system for x-ray detection has been developed. The CAMAC-based system has a Charge Coupled Device (CCD) as its active detection element. The electronics consist of a CAMAC-crate-based dedicated microprocessor coupled to arbitrary waveform generators, programmable timing, and ADC modules. The hardware flexibility achievable through this system enables one to use virtually any commercially available CCD. A dedicated CAMAC-based display driver allows for real-time imaging on a high-resolution color monitor. An optional front end consisting of a fiber-optic taper and a focusing optical lens system coupled to a phosphor screen allows for large area imaging. Further, programming flexibility, in which the detector can be used in different read-out modes, enables it to be exploited for time-resolved experiments. In one mode, sections of the CCD can be read-out with millisecond time-resolution and, in another, the use of the CCD as a storage device is exploited resulting in microsecond time-resolution. Three different CCDs with radically different read-out timings and waveforms have been tested: the TI 4849, a 39Ox584 pixel array; TC 215, a 1024x1O24 pixel array; and the TH 7883, a 576x384 pixel array. The TC 215 and TI 4849 are single-phase CCDs manufactured by Texas Instruments, and the TH 7883 is a four-phase device manufactured by Thomson-CSF. The CCD characterized for uniformity, charge transfer efficiency (CTE), linearity, and sensitivity is the TC215

  2. Window contamination on Expose-R

    Science.gov (United States)

    Demets, R.; Bertrand, M.; Bolkhovitinov, A.; Bryson, K.; Colas, C.; Cottin, H.; Dettmann, J.; Ehrenfreund, P.; Elsaesser, A.; Jaramillo, E.; Lebert, M.; van Papendrecht, G.; Pereira, C.; Rohr, T.; Saiagh, K.

    2015-01-01

    Expose is a multi-user instrument for astrobiological and astrochemical experiments in space. Installed at the outer surface of the International Space Station, it enables investigators to study the impact of the open space environment on biological and biochemical test samples. Two Expose missions have been completed so far, designated as Expose-E (Rabbow et al. 2012) and Expose-R (Rabbow et al. this issue). One of the space-unique environmental factors offered by Expose is full-spectrum, ultraviolet (UV)-rich electromagnetic radiation from the Sun. This paper describes and analyses how on Expose-R, access of the test samples to Solar radiation degraded during space exposure in an unpredicted way. Several windows in front of the Sun-exposed test samples acquired a brown shade, resulting in a reduced transparency in visible light, UV and vacuum UV (VUV). Post-flight investigations revealed the discolouration to be caused by a homogenous film of cross-linked organic polymers at the inside of the windows. The chemical signature varied per sample carrier. No such films were found on windows from sealed, pressurized compartments, or on windows that had been kept out of the Sun. This suggests that volatile compounds originating from the interior of the Expose facility were cross-linked and photo-fixed by Solar irradiation at the rear side of the windows. The origin of the volatiles was not fully identified; most probably there was a variety of sources involved including the biological test samples, adhesives, plastics and printed circuit boards. The outer surface of the windows (pointing into space) was chemically impacted as well, with a probable effect on the transparency in VUV. The reported analysis of the window contamination on Expose-R is expected to help the interpretation of the scientific results and offers possibilities to mitigate this problem on future missions - in particular Expose-R2, the direct successor of Expose-R.

  3. Declass 2 (2002) = KH-7 and KH-9 Global Camera Photos: 1963 - 1980

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Keyhole (KH) satellite systems KH-7 and KH-9 acquired photographs of the Earth's surface with a telescopic camera system and transported the exposed film through...

  4. The interaction of DNA gyrase with the bacterial toxin CcdB

    DEFF Research Database (Denmark)

    Kampranis, S C; Howells, A J; Maxwell, A

    1999-01-01

    CcdB is a bacterial toxin that targets DNA gyrase. Analysis of the interaction of CcdB with gyrase reveals two distinct complexes. An initial complex (alpha) is formed by direct interaction between GyrA and CcdB; this complex can be detected by affinity column and gel-shift analysis, and has a pr...

  5. Characterization of a CCD array for Bragg spectroscopy

    CERN Document Server

    Indelicato, P J; Gotta, D; Hennebach, M; Le Bigot, E O; Nelms, N; Simons, L M; Trassinelli, M; Bigot, Eric-Olivier Le; David, Christian; Gotta, Detlev; Hennebach, Maik; Indelicato, Paul; Nelms, Nick; Simons, Leopold M.; Trassinelli, Martino

    2006-01-01

    The average pixel distance as well as the relative orientation of an array of 6 CCD detectors have been measured with accuracies of about 0.5 nm and 50 $\\mu$rad, respectively. Such a precision satisfies the needs of modern crystal spectroscopy experiments in the field of exotic atoms and highly charged ions. Two different measurements have been performed by illuminating masks in front of the detector array by remote sources of radiation. In one case, an aluminum mask was irradiated with X-rays and in a second attempt, a nanometric quartz wafer was illuminated by a light bulb. Both methods gave consistent results with a smaller error for the optical method. In addition, the thermal expansion of the CCD detectors was characterized between -105 C and -40 C.

  6. Optomechanical System Development of the AWARE Gigapixel Scale Camera

    Science.gov (United States)

    Son, Hui S.

    Electronic focal plane arrays (FPA) such as CMOS and CCD sensors have dramatically improved to the point that digital cameras have essentially phased out film (except in very niche applications such as hobby photography and cinema). However, the traditional method of mating a single lens assembly to a single detector plane, as required for film cameras, is still the dominant design used in cameras today. The use of electronic sensors and their ability to capture digital signals that can be processed and manipulated post acquisition offers much more freedom of design at system levels and opens up many interesting possibilities for the next generation of computational imaging systems. The AWARE gigapixel scale camera is one such computational imaging system. By utilizing a multiscale optical design, in which a large aperture objective lens is mated with an array of smaller, well corrected relay lenses, we are able to build an optically simple system that is capable of capturing gigapixel scale images via post acquisition stitching of the individual pictures from the array. Properly shaping the array of digital cameras allows us to form an effectively continuous focal surface using off the shelf (OTS) flat sensor technology. This dissertation details developments and physical implementations of the AWARE system architecture. It illustrates the optomechanical design principles and system integration strategies we have developed through the course of the project by summarizing the results of the two design phases for AWARE: AWARE-2 and AWARE-10. These systems represent significant advancements in the pursuit of scalable, commercially viable snapshot gigapixel imaging systems and should serve as a foundation for future development of such systems.

  7. The TESS camera: modeling and measurements with deep depletion devices

    Science.gov (United States)

    Woods, Deborah F.; Vanderspek, Roland; MacDonald, Robert; Morgan, Edward; Villasenor, Joel; Thayer, Carolyn; Burke, Barry; Chesbrough, Christian; Chrisp, Michael; Clark, Kristin; Furesz, Gabor; Gonzales, Alexandria; Nguyen, Tam; Prigozhin, Gregory; Primeau, Brian; Ricker, George; Sauerwein, Timothy; Suntharalingam, Vyshnavi

    2016-07-01

    The Transiting Exoplanet Survey Satellite, a NASA Explorer-class mission in development, will discover planets around nearby stars, most notably Earth-like planets with potential for follow up characterization. The all-sky survey requires a suite of four wide field-of-view cameras with sensitivity across a broad spectrum. Deep depletion CCDs with a silicon layer of 100 μm thickness serve as the camera detectors, providing enhanced performance in the red wavelengths for sensitivity to cooler stars. The performance of the camera is critical for the mission objectives, with both the optical system and the CCD detectors contributing to the realized image quality. Expectations for image quality are studied using a combination of optical ray tracing in Zemax and simulations in Matlab to account for the interaction of the incoming photons with the 100 μm silicon layer. The simulations include a probabilistic model to determine the depth of travel in the silicon before the photons are converted to photo-electrons, and a Monte Carlo approach to charge diffusion. The charge diffusion model varies with the remaining depth for the photo-electron to traverse and the strength of the intermediate electric field. The simulations are compared with laboratory measurements acquired by an engineering unit camera with the TESS optical design and deep depletion CCDs. In this paper we describe the performance simulations and the corresponding measurements taken with the engineering unit camera, and discuss where the models agree well in predicted trends and where there are differences compared to observations.

  8. Altering Interline Transfer In A CCD To Reduce Saturation

    Science.gov (United States)

    Rentsch, Edward M.

    1991-01-01

    In proposed interline-transfer timing scheme for charge-coupled-device (CCD) video imaging array, charges accumulated during some fraction of frame period swept out and dumped to prevent overloading and saturation in intensely illuminated photosites. Excess charges swept out at highest possible rate, while charges used for imaging read out at rate lower but was highest rate that provides complete transfer of charge on array and handled by subsequent signal-processing equipment.

  9. Stable vacuum UV CCD detectors designed for space flight experiments

    Science.gov (United States)

    Socker, Dennis G.; Marchywka, Mike; Taylor, G. C.; Levine, P.; Rios, R.; Shallcross, F.; Hughes, G.

    1993-01-01

    Thinned, backside-illuminated, p-channel CCD images are under development which can exploit the surface potential in VUV applications, yielding enhanced quantum efficiency to wavelengths as short as 1100 A. The current goal is production of large-format, 5-micron pixel imagers for spectrographic and imaging VUV spaceflight experiments. Model predictions of the effect of device design on quantum efficiency, well capacity, and crosstalk are presented for such 5-micron-approaching pixel sizes.

  10. Wavelength Calibration Accuracy for the STIS CCD and MAMA Modes

    Science.gov (United States)

    Pascucci, Ilaria; Hodge, Phil; Proffitt, Charles R.; Ayres, T.

    2011-03-01

    Two calibration programs were carried out to determine the accuracy of the wavelength solutions for the most used STIS CCD and MAMA modes after Servicing Mission 4. We report here on the analysis of this dataset and show that the STIS wavelength solution has not changed after SM4. We also show that a typical accuracy for the absolute wavelength zero-points is 0.1 pixels while the relative wavelength accuracy is 0.2 pixels.

  11. X-ray pinhole camera setups used in the Atomki ECR Laboratory for plasma diagnostics.

    Science.gov (United States)

    Rácz, R; Biri, S; Pálinkás, J; Mascali, D; Castro, G; Caliri, C; Romano, F P; Gammino, S

    2016-02-01

    Imaging of the electron cyclotron resonance (ECR) plasmas by using CCD camera in combination with a pinhole is a non-destructive diagnostics method to record the strongly inhomogeneous spatial density distribution of the X-ray emitted by the plasma and by the chamber walls. This method can provide information on the location of the collisions between warm electrons and multiple charged ions/atoms, opening the possibility to investigate the direct effect of the ion source tuning parameters to the plasma structure. The first successful experiment with a pinhole X-ray camera was carried out in the Atomki ECR Laboratory more than 10 years ago. The goal of that experiment was to make the first ECR X-ray photos and to carry out simple studies on the effect of some setting parameters (magnetic field, extraction, disc voltage, gas mixing, etc.). Recently, intensive efforts were taken to investigate now the effect of different RF resonant modes to the plasma structure. Comparing to the 2002 experiment, this campaign used wider instrumental stock: CCD camera with a lead pinhole was placed at the injection side allowing X-ray imaging and beam extraction simultaneously. Additionally, Silicon Drift Detector (SDD) and High Purity Germanium (HPGe) detectors were installed to characterize the volumetric X-ray emission rate caused by the warm and hot electron domains. In this paper, detailed comparison study on the two X-ray camera and detector setups and also on the technical and scientific goals of the experiments is presented. PMID:26931959

  12. X-ray pinhole camera setups used in the Atomki ECR Laboratory for plasma diagnostics.

    Science.gov (United States)

    Rácz, R; Biri, S; Pálinkás, J; Mascali, D; Castro, G; Caliri, C; Romano, F P; Gammino, S

    2016-02-01

    Imaging of the electron cyclotron resonance (ECR) plasmas by using CCD camera in combination with a pinhole is a non-destructive diagnostics method to record the strongly inhomogeneous spatial density distribution of the X-ray emitted by the plasma and by the chamber walls. This method can provide information on the location of the collisions between warm electrons and multiple charged ions/atoms, opening the possibility to investigate the direct effect of the ion source tuning parameters to the plasma structure. The first successful experiment with a pinhole X-ray camera was carried out in the Atomki ECR Laboratory more than 10 years ago. The goal of that experiment was to make the first ECR X-ray photos and to carry out simple studies on the effect of some setting parameters (magnetic field, extraction, disc voltage, gas mixing, etc.). Recently, intensive efforts were taken to investigate now the effect of different RF resonant modes to the plasma structure. Comparing to the 2002 experiment, this campaign used wider instrumental stock: CCD camera with a lead pinhole was placed at the injection side allowing X-ray imaging and beam extraction simultaneously. Additionally, Silicon Drift Detector (SDD) and High Purity Germanium (HPGe) detectors were installed to characterize the volumetric X-ray emission rate caused by the warm and hot electron domains. In this paper, detailed comparison study on the two X-ray camera and detector setups and also on the technical and scientific goals of the experiments is presented.

  13. X-ray pinhole camera setups used in the Atomki ECR Laboratory for plasma diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Rácz, R., E-mail: rracz@atomki.hu; Biri, S.; Pálinkás, J. [Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/C, H-4026 Debrecen (Hungary); Mascali, D.; Castro, G.; Caliri, C.; Gammino, S. [Instituto Nazionale di Fisica Nucleare—Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania (Italy); Romano, F. P. [Instituto Nazionale di Fisica Nucleare—Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania (Italy); CNR, Istituto per i Beni Archeologici e Monumentali, Via Biblioteca 4, 95124 Catania (Italy)

    2016-02-15

    Imaging of the electron cyclotron resonance (ECR) plasmas by using CCD camera in combination with a pinhole is a non-destructive diagnostics method to record the strongly inhomogeneous spatial density distribution of the X-ray emitted by the plasma and by the chamber walls. This method can provide information on the location of the collisions between warm electrons and multiple charged ions/atoms, opening the possibility to investigate the direct effect of the ion source tuning parameters to the plasma structure. The first successful experiment with a pinhole X-ray camera was carried out in the Atomki ECR Laboratory more than 10 years ago. The goal of that experiment was to make the first ECR X-ray photos and to carry out simple studies on the effect of some setting parameters (magnetic field, extraction, disc voltage, gas mixing, etc.). Recently, intensive efforts were taken to investigate now the effect of different RF resonant modes to the plasma structure. Comparing to the 2002 experiment, this campaign used wider instrumental stock: CCD camera with a lead pinhole was placed at the injection side allowing X-ray imaging and beam extraction simultaneously. Additionally, Silicon Drift Detector (SDD) and High Purity Germanium (HPGe) detectors were installed to characterize the volumetric X-ray emission rate caused by the warm and hot electron domains. In this paper, detailed comparison study on the two X-ray camera and detector setups and also on the technical and scientific goals of the experiments is presented.

  14. Methode nouvelle pour la mesure CCD du diametre solaire avec un astrolabe. A new method for CCD measurements of the solar diameter with an astrolabe

    Science.gov (United States)

    Sinceac, V.; Chollet, F.; Laclare, F.; Delmas, C.

    1998-03-01

    the luminosity function along each of the 256 useful lines (the matrix is 512 by 512 pixels). This means that a numerical derivation is performed on every other line of the CCD video camera which has to stand as vertical as possible. Then, for every frame, and through the 256 points, a parabola is fitted, using the least squares method. The top of this parabola materializes the prospective characteristic point. The sets of such points associated with the corresponding times of acquisition, are collected for both images and the exact time of contact of the two images may be obtained. This time is also the time when the solar edge crosses the almucantar. The results for the semi-diameter obtained during 1996 campaign are derived from sixty measurements with the revolving mask and sixty seven without it, performed on the Solar Astrolabe. They give a mean value of 959\\farcs39 +/- 0\\farcs 03 with a scatter of 0\\farcs 29. It is interesting to remark that the values of the error bar and the scatter obtained do not depend on the definition of the Solar edge, whereas the mean value does depend on it. It is noticed that going with the method is made a systematic error which slightly shrinks the diameter, but this value can be known statistically and the correction can easily be done. Choosing the best definition of the Solar edge will be the matter of a following article. The main advantage of such a digital acquisition procedure has to be stressed, as it enables to store the full data for further reference and, if possible, better future processing.

  15. High-sensitivity CCD-based x-ray detector

    International Nuclear Information System (INIS)

    The detector is designed for imaging measurements requiring relatively high sensitivity and high spatial resolution. The detector can discriminate single X-ray photons, yet has the wide dynamic range (∼10000:1) associated with integrating detectors. A GdO2S2 phosphor screen converts the incoming X-ray image into an optical image. The optical image is coupled (without demagnification) to the CCD image sensor using a fiber optic faceplate. The CCD (Philips Semiconductors) has an area of 4.9 x 8.6 cm with 4000 x 7000 12 μm pixels. A single 12 keV X-ray photon produces a signal of 100 e-. With 2 x 2 pixel binning, the total noise per 24 μm pixel in a 100 s image is ∼30 e-, the detective quantum efficiency is >0.6 at 1 X-ray photon per pixel, and the full image can be read out in <4 s. The spatial resolution is 50 μm. The CCD readout system is fully computer-controlled, allowing flexible operation in time-resolved experiments. The detector has been characterized using visible-light images, X-ray images and time-resolved muscle diffraction measurements.

  16. HST/WFC3: understanding and mitigating radiation damage effects in the CCD detectors

    Science.gov (United States)

    Baggett, S. M.; Anderson, J.; Sosey, M.; Gosmeyer, C.; Bourque, M.; Bajaj, V.; Khandrika, H.; Martlin, C.

    2016-07-01

    At the heart of the Hubble Space Telescope Wide Field Camera 3 (HST/WFC3) UVIS channel is a 4096x4096 pixel e2v CCD array. While these detectors continue to perform extremely well after more than 7 years in low-earth orbit, the cumulative effects of radiation damage are becoming increasingly evident. The result is a continual increase of the hotpixel population and the progressive loss in charge-transfer efficiency (CTE) over time. The decline in CTE has two effects: (1) it reduces the detected source flux as the defects trap charge during readout and (2) it systematically shifts source centroids as the trapped charge is later released. The flux losses can be significant, particularly for faint sources in low background images. In this report, we summarize the radiation damage effects seen in WFC3/UVIS and the evolution of the CTE losses as a function of time, source brightness, and image-background level. In addition, we discuss the available mitigation options, including target placement within the field of view, empirical stellar photometric corrections, post-flash mode and an empirical pixel-based CTE correction. The application of a post-flash has been remarkably effective in WFC3 at reducing CTE losses in low-background images for a relatively small noise penalty. Currently, all WFC3 observers are encouraged to consider post-flash for images with low backgrounds. Finally, a pixel-based CTE correction is available for use after the images have been acquired. Similar to the software in use in the HST Advanced Camera for Surveys (ACS) pipeline, the algorithm employs an observationally-defined model of how much charge is captured and released in order to reconstruct the image. As of Feb 2016, the pixel-based CTE correction is part of the automated WFC3 calibration pipeline. Observers with pre-existing data may request their images from MAST (Mikulski Archive for Space Telescopes) to obtain the improved products.

  17. The readout and control system of the Dark Energy Camera

    Science.gov (United States)

    Honscheid, Klaus; Elliott, Ann; Annis, James; Bonati, Marco; Buckley-Geer, Elizabeth; Castander, Francisco; daCosta, Luiz; Fausti, Angelo; Karliner, Inga; Kuhlmann, Steve; Neilsen, Eric; Patton, Kenneth; Reil, Kevin; Roodman, Aaron; Thaler, Jon; Serrano, Santiago; Soares Santos, Marcelle; Suchyta, Eric

    2012-09-01

    The Dark Energy Camera (DECam) is a new 520 Mega Pixel CCD camera with a 3 square degree field of view designed for the Dark Energy Survey (DES). DES is a high precision, multi-bandpass, photometric survey of 5000 square degrees of the southern sky. DECam is currently being installed at the prime focus of the Blanco 4-m telescope at the Cerro- Tololo International Observatory (CTIO). In this paper we describe SISPI, the data acquisition and control system of the Dark Energy Camera. SISPI is implemented as a distributed multi-processor system with a software architecture based on the Client-Server and Publish-Subscribe design patterns. The underlying message passing protocol is based on PYRO, a powerful distributed object technology system written entirely in Python. A distributed shared variable system was added to support exchange of telemetry data and other information between different components of the system. We discuss the SISPI infrastructure software, the image pipeline, the observer console and user interface architecture, image quality monitoring, the instrument control system, and the observation strategy tool.

  18. Precision multi-band photometry with a DSLR camera

    CERN Document Server

    Zhang, M; Penev, K; Csubry, Z; Hartman, J D; Bhatti, W; de Val-Borro, M

    2015-01-01

    Ground-based exoplanet surveys such as SuperWASP, HATNet and KELT have discovered close to two hundred transiting extrasolar planets in the past several years. The strategy of these surveys is to look at a large field of view and measure the brightnesses of its bright stars to around half a percent per point precision, which is adequate for detecting hot Jupiters. Typically, these surveys use CCD detectors to achieve high precision photometry. These CCDs, however, are expensive relative to other consumer-grade optical imaging devices, such as digital single-lens reflex cameras (DSLRs). We look at the possibility of using a digital single-lens reflex camera for precision photometry. Specifically, we used a Canon EOS 60D camera that records light in 3 colors simultaneously. The DSLR was integrated into the HATNet survey and collected observations for a month, after which photometry was extracted for 6600 stars in a selected stellar field. We found that the DSLR achieves a best-case median absolute deviation (MA...

  19. LiCHy: The CAF’s LiDAR, CCD and Hyperspectral Integrated Airborne Observation System

    Directory of Open Access Journals (Sweden)

    Yong Pang

    2016-05-01

    Full Text Available We describe the design, implementation and performance of a novel airborne system, which integrates commercial waveform LiDAR, CCD (Charge-Coupled Device camera and hyperspectral sensors into a common platform system. CAF’s (The Chinese Academy of Forestry LiCHy (LiDAR, CCD and Hyperspectral Airborne Observation System is a unique system that permits simultaneous measurements of vegetation vertical structure, horizontal pattern, and foliar spectra from different view angles at very high spatial resolution (~1 m on a wide range of airborne platforms. The horizontal geo-location accuracy of LiDAR and CCD is about 0.5 m, with LiDAR vertical resolution and accuracy 0.15 m and 0.3 m, respectively. The geo-location accuracy of hyperspectral image is within 2 pixels for nadir view observations and 5–7 pixels for large off-nadir observations of 55° with multi-angle modular when comparing to LiDAR product. The complementary nature of LiCHy’s sensors makes it an effective and comprehensive system for forest inventory, change detection, biodiversity monitoring, carbon accounting and ecosystem service evaluation. The LiCHy system has acquired more than 8000 km2 of data over typical forests across China. These data are being used to investigate potential LiDAR and optical remote sensing applications in forest management, forest carbon accounting, biodiversity evaluation, and to aid in the development of similar satellite configurations. This paper describes the integration of the LiCHy system, the instrument performance and data processing workflow. We also demonstrate LiCHy’s data characteristics, current coverage, and potential vegetation applications.

  20. Using a delta-doped CCD to determine the energy of a low-energy particle

    Science.gov (United States)

    Nikzad, Shouleh (Inventor); Croley, Donald R. (Inventor); Murphy, Gerald B. (Inventor)

    2001-01-01

    The back surface of a thinned charged-coupled device (CCD) is treated to eliminate the backside potential well that appears in a conventional thinned CCD during backside illumination. The backside of the CCD includes a delta layer of high-concentration dopant confined to less than one monolayer of the crystal semiconductor. The thinned, delta-doped CCD is used to determine the energy of a very low-energy particle that penetrates less than 1.0 nm into the CCD, such as a proton having energy less than 10 keV.

  1. Novel gamma cameras

    International Nuclear Information System (INIS)

    The gamma-ray cameras described are based on radiation imaging devices which permit the direct recording of the distribution of radioactive material from a radiative source, such as a human organ. They consist in principle of a collimator, a converter matrix converting gamma photons to electrons, and an electron image multiplier producing a multiplied electron output, and means for reading out the information. The electron image multiplier is a device which produces a multiplied electron image. It can be in principle, either gas avalanche electron multiplier or a multi-channel plate. The multi-channel plate employed is a novel device, described elsewhere. The three described embodiments, in which the converter matrix can be either of metal type or of scintillation crystal type, were designed and are being developed

  2. The Circular Camera Movement

    DEFF Research Database (Denmark)

    Hansen, Lennard Højbjerg

    2014-01-01

    It has been an accepted precept in film theory that specific stylistic features do not express specific content. Nevertheless, it is possible to find many examples in the history of film in which stylistic features do express specific content: for instance, the circular camera movement is used...... repeatedly to convey the feeling of a man and a woman falling in love. This raises the question of why producers and directors choose certain stylistic features to narrate certain categories of content. Through the analysis of several short film and TV clips, this article explores whether...... or not there are perceptual aspects related to specific stylistic features that enable them to be used for delimited narrational purposes. The article further attempts to reopen this particular stylistic debate by exploring the embodied aspects of visual perception in relation to specific stylistic features...

  3. Noise and dark performance for the FIREBall-2 EMCCD delta-doped UV optimized CCD detector

    Science.gov (United States)

    Hamden, Erika T.; Lingner, Nicole; Kyne, Gillian; Morrissey, Patrick; Martin, Christopher D.; FIREBall-2 Team

    2016-01-01

    The Faint Intergalactic Redshifted Emission Balloon (FIREBall-2) is a UV multi-object spectrograph experiment designed to observe low-density emission from HI, CIV, and OVI in the circum-galactic medium (CGM) around low-redshift galaxies (z=0.3-1.0) from a high altitude balloon. To detect this diffuse emission, we have chosen to use a high-efficiency photon-counting EMCCD as part of FIREBall-2's detector system. The flight camera system includes a custom printed circuit board, a mechanical cryo-cooler, zeolite and charcoal getters, and a NUVU controller, for fast read-out speeds and waveform shaping. Here we report on overall detector system performance. We describe our characterization of detector noise from a delta-doped, anti-reflection-coated, electron-multiplying e2v CCD201-20. We describe our use of a NUVU controller to create custom waveforms that reduce clock-induced charge (CIC). We detail the clock frequencies, waveform shapes, and well depths required to reduce parallel and serial CIC to acceptable levels for our application (~10-3 events/pix/frame), at a range of substrate voltages. We also describe dark current measurements at several temperatures, including at our operating temperature of -115°C, with the flight set-up.

  4. Imaging the Moon II: Webcam CCD Observations and Analysis (a Two-Week Lab for Non-Majors)

    Science.gov (United States)

    Sato, T.

    2014-07-01

    Imaging the Moon is a successful two-week lab involving real sky observations of the Moon in which students make telescopic observations and analyze their own images. Originally developed around the 35 mm film camera, a common household object adapted for astronomical work, the lab now uses webcams as film photography has evolved into an obscure specialty technology and increasing numbers of students have little familiarity with it. The printed circuit board with the CCD is harvested from a commercial webcam and affixed to a tube to mount on a telescope in place of an eyepiece. Image frames are compiled to form a lunar mosaic, and crater sizes are measured. Students also work through the logistical steps of telescope time assignment and scheduling. They learn to keep a schedule and work with uncertainties of weather in ways paralleling research observations. Because there is no need for a campus observatory, this lab can be replicated at a wide variety of institutions.

  5. Influence of scattered light on accurate CCD flat fielding --- necessity of modifying baffles of some existent reflectors

    Science.gov (United States)

    Yao, B. A.; Zhang, C. S.; Sheng, C. J.; Peng, Y. L.

    2005-07-01

    This paper is the continuation of paper [1]. In this paper we further show that the difference between twilight flat field and night sky exposure is mainly due to the existence of scattered light. Like Grundahl and Sorensen, we also made the pinhole images of the 1.56m at the Shanghai Observatory and the 63cm of the Nanjing University to show the existence of scattered light intuitively. Both the 1.56m and the 63cm reflectors have normal designed baffles. Therefore it is the common weakness of all standard designed reflectors having only two baffles mounted in front of the primary and secondary mirrors which are not enough to protect the CCD cameras from scattered light in getting accurate flat fields. It is of great importance to modify the primary mirror baffle of all similar reflectors in order to get more accurate flat fielding.

  6. Cross calibration of INSAT 3A CCD channel radiances with IRS P6 AWiFS sensor

    Indian Academy of Sciences (India)

    S K Singh; B K Bhattacharya; A V Kulkarni

    2013-08-01

    Indian National Satellite (INSAT) 3A was launched in the year 2003 with communication and remote sensing payloads. The later payloads contain very high resolution radiometer (VHRR) and charge coupled devices (CCD) camera. In this paper, post-launch calibration of INSAT 3A CCD is discussed. A cross radiometric calibration was carried out with well calibrated advanced wide field of view sensor (AWiFS) of Indian Remote Sensing Satellite (IRS P6). Three concurrent scenes of December, January and February were used in this study. Calibration was carried out under different land cover classes such as snow, vegetation, forest, water and cloud. Regression analysis suggests correlation coefficient of 0.95, 0.92 and 0.60 for Red, NIR and SWIR channels with slope values 1.839, 1.589 and 2.232, respectively. New calibration coefficients were used to estimate at-sensor radiance and reflectance in all the three channels. Dynamic range of reflectances was found to be improved by using new calibration coefficients. Normalized difference snow index and vegetation index (NDSI and NDVI) have shown an improvement with new coefficients and were found closer to represent in situ data of different land covers and cloud.

  7. The Near Earth Object Surveillance Satellite: Mission status and CCD evolution after 18 months on-orbit

    Science.gov (United States)

    Wallace, B.; Scott, R.; Sale, M.

    2014-09-01

    The Near Earth Object Surveillance Satellite (NEOSSat) is a small telescope equipped microsatellite designed to perform both Space Situational Awareness (SSA) experiments and asteroid detection. NEOSSat was launched on 25 February 2013, however, due to time pressures, NEOSSat was launched with only the minimal software required to keep the spacecraft safe. The time pressure also resulted in the spacecraft undergoing reduced system and environmental testing on the ground. The full software suite, required to obtain imagery and maintain stable pointing, has since been uploaded to the spacecraft. NEOSSat has obtained imagery since June 2013, with the shutter both open and closed, but as of March 2014 has not achieved the fine pointing required to obtain scientifically useful data. The collected imagery is being used to characterize the on-board CCD camera. While gain and dark current values agree with pre-launch values, unexpected artefacts have appeared in the images. Methods for mitigating the artefacts through image processing have been developed, and spacecraft-level fixes are currently being investigated. In addition, damage from high energy particles impacting the CCD has produced hot pixels in imagery. We have been able to measure the evolution of these hot pixels over several months, both in terms of numbers and characteristics; these results will be presented. In addition, early results from the mission (image quality issues and evolution, early imagery examples), as well as the mission status (including fine pointing), will be discussed.

  8. High-speed radiometric imaging with a gated, intensified, digitally controlled camera

    Science.gov (United States)

    Ross, Charles C.; Sturz, Richard A.

    1997-05-01

    The development of an advanced instrument for real-time radiometric imaging of high-speed events is described. The Intensified Digitally-Controlled Gated (IDG) camera is a microprocessor-controlled instrument based on an intensified CCD that is specifically designed to provide radiometric optical data. The IDG supports a variety of camera- synchronous and camera-asynchronous imaging tasks in both passive imaging and active laser range-gated applications. It features both automatic and manual modes of operation, digital precision and repeatability, and ease of use. The IDG produces radiometric imagery by digitally controlling the instrument's optical gain and exposure duration, and by encoding and annotating the parameters necessary for radiometric analysis onto the resultant video signal. Additional inputs, such as date, time, GPS, IRIG-B timing, and other data can also be encoded and annotated. The IDG optical sensitivity can be readily calibrated, with calibration data tables stored in the camera's nonvolatile flash memory. The microprocessor then uses this data to provide a linear, calibrated output. The IDG possesses both synchronous and asynchronous imaging modes in order to allow internal or external control of exposure, timing, and direct interface to external equipment such as event triggers and frame grabbers. Support for laser range-gating is implemented by providing precise asynchronous CCD operation and nanosecond resolution of the intensifier photocathode gate duration and timing. Innovative methods used to control the CCD for asynchronous image capture, as well as other sensor and system considerations relevant to high-speed imaging are discussed in this paper.

  9. Subaru next-generation wide-field camera: HyperSuprime

    Science.gov (United States)

    Komiyama, Yutaka; Miyazaki, Satoshi; Nakaya, Hidehiko; Furusawa, Hisanori; Takeshi, Kunio

    2004-09-01

    We summarize the design and the specification of a next generation instrument for Subaru Telescope: a very wide-field (2°φ) CCD camera which we name HyperSuprime. The latest design of the corrector ensures 80% encircled energy diameter of 0".3 from 600 nm to 1100 nm over the 2°φ field of view. The size of the focal plane is 612 mm in diameter and covered by about 170 four side buttable 2kx4k CCDs. Fully depleted CCD which is now being developed is the primary candidate for HyperSuprime. The readout electronics is connected behind the CCD and this CCD package is screwed to the cold plate with three positioning pins. The large entrance window of the dewar is supported with additional ribs so that the dewar is evacuated and CCDs are cooled down to about -80°C. HyperSuprime equips with a filter exchanger which can accommodate four large mosaicked filters and a roll-type shutter.

  10. Research of Camera Synchronous Capture System Under External Trigger Mode%外触发方式下相机同步抓拍系统研究

    Institute of Scientific and Technical Information of China (English)

    李超; 刘树昌; 刘鹏; 周大勇; 王雪

    2014-01-01

    As the laser pulse frequency is low and the pulse’s width is ns grade in the pulse laser detection system ,it’s difficult to control the accurate exposure moment of the digital CCD camera .In order to overcome the difficulty that the trigger signal for the digital CCD camera and the laser pulse signal are not synchronous , a method that combining the “light trigger ,electrical synchronization” with advanced prediction is put for-ward .BD2/GPS module provided the PPS pulse signal as the clock reference ,combined with the FPGA’s high speed characteristic ,so the digital CCD camera could capture the laser spot image exactly ,and control the best integral time of the digital CCD camera .The experiment indicates that this method can improve the capturing precision of the digital CCD camera and the SNR of laser spot image .%脉冲激光检测系统中,由于激光器发射的激光脉冲频率低,且脉宽仅为纳秒级,所以在远距离测试时,很难控制数字 CCD(Charge Coupled Device)相机的精准曝光时刻。为了克服触发信号与激光脉冲信号不同步的问题,本文提出了“光触发,电同步”与“超前预测”相结合的方法。以 BD2(BeiDou2 Navigation Satel-lite System )/GPS(Global Positioning System )模块提供的精确秒脉冲 pps(pulse per second)信号作为时钟基准,同时结合 FPGA(Field Programmable Gate Array )高速的特点,实现数字 CCD 相机对激光光斑图像的准确捕获,控制数字 CCD 相机的最佳积分时间。实验结果表明,该方法不仅提高了数字 CCD 相机的抓拍精度,也提高了图像的信噪比。

  11. Single photon detection and localization accuracy with an ebCMOS camera

    Energy Technology Data Exchange (ETDEWEB)

    Cajgfinger, T. [CNRS/IN2P3, Institut de Physique Nucléaire de Lyon, Villeurbanne F-69622 (France); Dominjon, A., E-mail: agnes.dominjon@nao.ac.jp [Université de Lyon, Université de Lyon 1, Lyon 69003 France. (France); Barbier, R. [CNRS/IN2P3, Institut de Physique Nucléaire de Lyon, Villeurbanne F-69622 (France); Université de Lyon, Université de Lyon 1, Lyon 69003 France. (France)

    2015-07-01

    The CMOS sensor technologies evolve very fast and offer today very promising solutions to existing issues facing by imaging camera systems. CMOS sensors are very attractive for fast and sensitive imaging thanks to their low pixel noise (1e-) and their possibility of backside illumination. The ebCMOS group of IPNL has produced a camera system dedicated to Low Light Level detection and based on a 640 kPixels ebCMOS with its acquisition system. After reminding the principle of detection of an ebCMOS and the characteristics of our prototype, we confront our camera to other imaging systems. We compare the identification efficiency and the localization accuracy of a point source by four different photo-detection devices: the scientific CMOS (sCMOS), the Charge Coupled Device (CDD), the Electron Multiplying CCD (emCCD) and the Electron Bombarded CMOS (ebCMOS). Our ebCMOS camera is able to identify a single photon source in less than 10 ms with a localization accuracy better than 1 µm. We report as well efficiency measurement and the false positive identification of the ebCMOS camera by identifying more than hundreds of single photon sources in parallel. About 700 spots are identified with a detection efficiency higher than 90% and a false positive percentage lower than 5. With these measurements, we show that our target tracking algorithm can be implemented in real time at 500 frames per second under a photon flux of the order of 8000 photons per frame. These results demonstrate that the ebCMOS camera concept with its single photon detection and target tracking algorithm is one of the best devices for low light and fast applications such as bioluminescence imaging, quantum dots tracking or adaptive optics.

  12. Single photon detection and localization accuracy with an ebCMOS camera

    Science.gov (United States)

    Cajgfinger, T.; Dominjon, A.; Barbier, R.

    2015-07-01

    The CMOS sensor technologies evolve very fast and offer today very promising solutions to existing issues facing by imaging camera systems. CMOS sensors are very attractive for fast and sensitive imaging thanks to their low pixel noise (1e-) and their possibility of backside illumination. The ebCMOS group of IPNL has produced a camera system dedicated to Low Light Level detection and based on a 640 kPixels ebCMOS with its acquisition system. After reminding the principle of detection of an ebCMOS and the characteristics of our prototype, we confront our camera to other imaging systems. We compare the identification efficiency and the localization accuracy of a point source by four different photo-detection devices: the scientific CMOS (sCMOS), the Charge Coupled Device (CDD), the Electron Multiplying CCD (emCCD) and the Electron Bombarded CMOS (ebCMOS). Our ebCMOS camera is able to identify a single photon source in less than 10 ms with a localization accuracy better than 1 μm. We report as well efficiency measurement and the false positive identification of the ebCMOS camera by identifying more than hundreds of single photon sources in parallel. About 700 spots are identified with a detection efficiency higher than 90% and a false positive percentage lower than 5. With these measurements, we show that our target tracking algorithm can be implemented in real time at 500 frames per second under a photon flux of the order of 8000 photons per frame. These results demonstrate that the ebCMOS camera concept with its single photon detection and target tracking algorithm is one of the best devices for low light and fast applications such as bioluminescence imaging, quantum dots tracking or adaptive optics.

  13. Radiation camera motion correction system

    Science.gov (United States)

    Hoffer, P.B.

    1973-12-18

    The device determines the ratio of the intensity of radiation received by a radiation camera from two separate portions of the object. A correction signal is developed to maintain this ratio at a substantially constant value and this correction signal is combined with the camera signal to correct for object motion. (Official Gazette)

  14. Optical design of the comet Shoemaker-Levy speckle camera

    Energy Technology Data Exchange (ETDEWEB)

    Bissinger, H. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    An optical design is presented in which the Lick 3 meter telescope and a bare CCD speckle camera system was used to image the collision sites of the Shoemaker-Levy 9 comet with the Planet Jupiter. The brief overview includes of the optical constraints and system layout. The choice of a Risley prism combination to compensate for the time dependent atmospheric chromatic changes are described. Plate scale and signal-to-noise ratio curves resulting from imaging reference stars are compared with theory. Comparisons between un-corrected and reconstructed images of Jupiter`s impact sites. The results confirm that speckle imaging techniques can be used over an extended time period to provide a method to image large extended objects.

  15. Camera Gap Removal in SOLIS/VSM Images

    CERN Document Server

    Marble, Andrew R; Pevtsov, Alexei A

    2013-01-01

    The Vector Spectromagnetograph (VSM) instrument on the Synoptic Optical Longterm Investigations of the Sun (SOLIS) telescope is capable of obtaining spectropolarimetry for the full Sun (or a select latitudinal range) with one arcsecond spatial resolution and 0.05 Angstrom spectral resolution. This is achieved by scanning the Sun in declination and building up spectral cubes for multiple polarization states, utilizing a beamsplitter and two separate 2k x 2k CCD cameras. As a result, the eastern and western hemispheres of the Sun are separated in preliminary VSM images by a vertical gap with soft edges and variable position and width. Prior to the comprehensive analysis presented in this document, a trial-and-error approach to removing the gap had yielded an algorithm that was inconsistent, undocumented, and responsible for incorrectly eliminating too many image columns. Here we describe, in detail, the basis for a new, streamlined, and properly calibrated prescription for locating and removing the gap that is ...

  16. LISS-4 camera for Resourcesat

    Science.gov (United States)

    Paul, Sandip; Dave, Himanshu; Dewan, Chirag; Kumar, Pradeep; Sansowa, Satwinder Singh; Dave, Amit; Sharma, B. N.; Verma, Anurag

    2006-12-01

    The Indian Remote Sensing Satellites use indigenously developed high resolution cameras for generating data related to vegetation, landform /geomorphic and geological boundaries. This data from this camera is used for working out maps at 1:12500 scale for national level policy development for town planning, vegetation etc. The LISS-4 Camera was launched onboard Resourcesat-1 satellite by ISRO in 2003. LISS-4 is a high-resolution multi-spectral camera with three spectral bands and having a resolution of 5.8m and swath of 23Km from 817 Km altitude. The panchromatic mode provides a swath of 70Km and 5-day revisit. This paper briefly discusses the configuration of LISS-4 Camera of Resourcesat-1, its onboard performance and also the changes in the Camera being developed for Resourcesat-2. LISS-4 camera images the earth in push-broom mode. It is designed around a three mirror un-obscured telescope, three linear 12-K CCDs and associated electronics for each band. Three spectral bands are realized by splitting the focal plane in along track direction using an isosceles prism. High-speed Camera Electronics is designed for each detector with 12- bit digitization and digital double sampling of video. Seven bit data selected from 10 MSBs data by Telecommand is transmitted. The total dynamic range of the sensor covers up to 100% albedo. The camera structure has heritage of IRS- 1C/D. The optical elements are precisely glued to specially designed flexure mounts. The camera is assembled onto a rotating deck on spacecraft to facilitate +/- 26° steering in Pitch-Yaw plane. The camera is held on spacecraft in a stowed condition before deployment. The excellent imageries from LISS-4 Camera onboard Resourcesat-1 are routinely used worldwide. Such second Camera is being developed for Resourcesat-2 launch in 2007 with similar performance. The Camera electronics is optimized and miniaturized. The size and weight are reduced to one third and the power to half of the values in Resourcesat

  17. Development of a driving method suitable for ultrahigh-speed shooting in a 2M-fps 300k-pixel single-chip color camera

    Science.gov (United States)

    Yonai, J.; Arai, T.; Hayashida, T.; Ohtake, H.; Namiki, J.; Yoshida, T.; Etoh, T. Goji

    2012-03-01

    We have developed an ultrahigh-speed CCD camera that can capture instantaneous phenomena not visible to the human eye and impossible to capture with a regular video camera. The ultrahigh-speed CCD was specially constructed so that the CCD memory between the photodiode and the vertical transfer path of each pixel can store 144 frames each. For every one-frame shot, the electric charges generated from the photodiodes are transferred in one step to the memory of all the parallel pixels, making ultrahigh-speed shooting possible. Earlier, we experimentally manufactured a 1M-fps ultrahigh-speed camera and tested it for broadcasting applications. Through those tests, we learned that there are cases that require shooting speeds (frame rate) of more than 1M fps; hence we aimed to develop a new ultrahigh-speed camera that will enable much faster shooting speeds than what is currently possible. Since shooting at speeds of more than 200,000 fps results in decreased image quality and abrupt heating of the image sensor and drive circuit board, faster speeds cannot be achieved merely by increasing the drive frequency. We therefore had to improve the image sensor wiring layout and the driving method to develop a new 2M-fps, 300k-pixel ultrahigh-speed single-chip color camera for broadcasting purposes.

  18. The influence of electron multiplication and internal X-ray fluorescence on the performance of a scintillator-based gamma camera

    Energy Technology Data Exchange (ETDEWEB)

    Hall, David J., E-mail: d.j.hall@open.ac.uk [e2v centre for electronic imaging, The Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom); Holland, Andrew; Soman, Matthew [e2v centre for electronic imaging, The Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom)

    2012-06-21

    When considering the 'standard' gamma-camera, one might picture an array of photo-multiplier tubes or a similar array of small-area detectors. This array of imaging detectors would be attached to a corresponding array of scintillator modules (or a solid layer of scintillator) in order to give a high detection efficiency in the energy region of interest, usually 8-140 keV. Over recent years, developments of gamma-cameras capable of achieving much higher spatial resolutions have led to a new range of systems based on Charge-Coupled Devices with some form of signal multiplication between the scintillator and the CCD in order for one to distinguish the light output from the scintillator above the CCD noise. The use of an Electron-Multiplying Charge-Coupled Device (EM-CCD) incorporates the gain process within the CCD through a form of 'impact ionisation', however, the gain process introduces an 'excess noise factor' due to the probabilistic nature of impact ionisation and this additional noise consequently has an impact on the spatial and spectral resolution of the detector. Internal fluorescence in the scintillator, producing K-shell X-ray fluorescence photons that can be detected alongside the incident gamma-rays, also has a major impact on the imaging capabilities of gamma-cameras. This impact varies dramatically from the low spatial resolution to high spatial resolution camera system. Through a process of simulation and experimental testing focussed on the high spatial resolution (EM-CCD based) variant, the factors affecting the performance of gamma-camera systems are discussed and the results lead to important conclusions to be considered for the development of future systems. This paper presents a study into the influence of the EM-CCD gain process and the internal X-ray fluorescence in the scintillator on the performance of scintillator-based gamma cameras (CCD-based or otherwise), making use of Monte Carlo simulations to demonstrate

  19. Report on the eROSITA camera system

    Science.gov (United States)

    Meidinger, Norbert; Andritschke, Robert; Bornemann, Walter; Coutinho, Diogo; Emberger, Valentin; Hälker, Olaf; Kink, Walter; Mican, Benjamin; Müller, Siegfried; Pietschner, Daniel; Predehl, Peter; Reiffers, Jonas

    2014-07-01

    The eROSITA space telescope is currently developed for the determination of cosmological parameters and the equation of state of dark energy via evolution of clusters of galaxies. Furthermore, the instrument development was strongly motivated by the intention of a first imaging X-ray all-sky survey enabling measurements above 2 keV. eROSITA is a scientific payload on the Russian research satellite SRG. Its destination after launch is the Lagrangian point L2. The observational program of the observatory divides into an all-sky survey and pointed observations and takes in total about 7.5 years. The instrument comprises an array of 7 identical and parallel aligned telescopes. Each of the seven focal plane cameras is equipped with a PNCCD detector, an enhanced type of the XMM-Newton focal plane detector. This instrumentation permits spectroscopy and imaging of X-rays in the energy band from 0.3 keV to 10 keV with a field of view of 1.0 degree. The camera development is done at the Max-Planck-Institute for extraterrestrial physics. Key component of each camera is the PNCCD chip. This silicon sensor is a back-illuminated, fully depleted and column-parallel type of charge coupled device. The image area of the 450 micron thick frame-transfer CCD comprises an array of 384 x 384 pixels, each with a size of 75 micron x 75 micron. Readout of the signal charge that is generated by an incident X-ray photon in the CCD is accomplished by an ASIC, the so-called eROSITA CAMEX. It provides 128 parallel analog signal processing channels but multiplexes the signals finally to one output which feeds the detector signals to a fast 14-bit ADC. The read noise of this system is equivalent to a noise charge of about 2.5 electrons rms. We achieve an energy resolution close to the theoretical limit given by Fano noise (except for very low energies). For example, the FWHM at an energy of 5.9 keV is approximately 140 eV. The complete camera assembly comprises the camera head with the detector as

  20. Performance of a fluorescent screen and CCD camera as a two-dimensional dosimetry system for dynamic treatment techniques

    NARCIS (Netherlands)

    Boon, SN; van Luijk, P; Bohringer, T; Coray, A; Lomax, A; Pedroni, E; Schaffner, B; Schippers, JM

    2000-01-01

    A two-dimensionally position sensitive dosimetry system has been tested for different dosimetric applications in a radiation therapy facility with a scanning proton beam. The system consists of a scintillating (fluorescent) screen, mounted at the beam-exit side of a phantom and it is observed by a c

  1. Quantum spatial correlations in high-gain parametric down-conversion measured by means of a CCD camera

    DEFF Research Database (Denmark)

    Jedrkiewicz, O.; Brambilla, E.; Bache, Morten;

    2006-01-01

    We consider travelling-wave parametric down-conversion in the high-gain regime and present the experimental demonstration of the quantum character of the spatial fluctuations in the system. In addition to showing the presence of sub-shot noise fluctuations in the intensity difference, we demonstr...

  2. Multi-camera calibration based on openCV and multi-view registration

    Science.gov (United States)

    Deng, Xiao-ming; Wan, Xiong; Zhang, Zhi-min; Leng, Bi-yan; Lou, Ning-ning; He, Shuai

    2010-10-01

    For multi-camera calibration systems, a method based on OpenCV and multi-view registration combining calibration algorithm is proposed. First of all, using a Zhang's calibration plate (8X8 chessboard diagram) and a number of cameras (with three industrial-grade CCD) to be 9 group images shooting from different angles, using OpenCV to calibrate the parameters fast in the camera. Secondly, based on the corresponding relationship between each camera view, the computation of the rotation matrix and translation matrix is formulated as a constrained optimization problem. According to the Kuhn-Tucker theorem and the properties on the derivative of the matrix-valued function, the formulae of rotation matrix and translation matrix are deduced by using singular value decomposition algorithm. Afterwards an iterative method is utilized to get the entire coordinate transformation of pair-wise views, thus the precise multi-view registration can be conveniently achieved and then can get the relative positions in them(the camera outside the parameters).Experimental results show that the method is practical in multi-camera calibration .

  3. Medium Format Camera Evaluation Based on the Latest Phase One Technology

    Science.gov (United States)

    Tölg, T.; Kemper, G.; Kalinski, D.

    2016-06-01

    In early 2016, Phase One Industrial launched a new high resolution camera with a 100 MP CMOS sensor. CCD sensors excel at ISOs up to 200, but in lower light conditions, exposure time must be increased and Forward Motion Compensation (FMC) has to be employed to avoid smearing the images. The CMOS sensor has an ISO range of up to 6400, which enables short exposures instead of using FMC. This paper aims to evaluate the strengths of each of the sensor types based on real missions over a test field in Speyer, Germany, used for airborne camera calibration. The test field area has about 30 Ground Control Points (GCPs), which enable a perfect scenario for a proper geometric evaluation of the cameras. The test field includes both a Siemen star and scale bars to show any blurring caused by forward motion. The result of the comparison showed that both cameras offer high accuracy photogrammetric results with post processing, including triangulation, calibration, orthophoto and DEM generation. The forward motion effect can be compensated by a fast shutter speed and a higher ISO range of the CMOS-based camera. The results showed no significant differences between cameras.

  4. Periscope-camera system for visible and infrared imaging diagnostics on TFTR

    International Nuclear Information System (INIS)

    An optical diagnostic consisting of a periscope which relays images of the torus interior to an array of cameras is used on the Tokamak Fusion Test Reactor (TFTR) to view plasma discharge phenomena and inspect vacuum vessel internal structures in both visible and near-infrared wavelength regions. Three periscopes view through 20-cm-diameter fused-silica windows which are spaced around the torus midplane to provide a viewing coverage of approximately 75% of the vacuum vessel internal surface area. The periscopes have f/8 optics and motor-driven controls for focusing, magnification selection (50, 200, and 600 field of view), elevation and azimuth setting, mast rotation, filter selection, iris aperture, and viewing port selection. The four viewing ports on each periscope are equipped with multiple imaging devices which include: (1) an inspection eyepiece, (2) standard (RCA TC2900) and fast (RETICON) framing rate television cameras, (3) a PtSi CCD infrared imaging camera, (4) a 35 mm Nikon F3 still camera, or (5) a 16 mm Locam II movie camera with variable framing up to 500 fps. Operation of the periscope-camera system is controlled either locally or remotely through a computer-CAMAC interface. A description of the equipment and examples of its application are presented

  5. Camera sensitivity study

    Science.gov (United States)

    Schlueter, Jonathan; Murphey, Yi L.; Miller, John W. V.; Shridhar, Malayappan; Luo, Yun; Khairallah, Farid

    2004-12-01

    As the cost/performance Ratio of vision systems improves with time, new classes of applications become feasible. One such area, automotive applications, is currently being investigated. Applications include occupant detection, collision avoidance and lane tracking. Interest in occupant detection has been spurred by federal automotive safety rules in response to injuries and fatalities caused by deployment of occupant-side air bags. In principle, a vision system could control airbag deployment to prevent this type of mishap. Employing vision technology here, however, presents a variety of challenges, which include controlling costs, inability to control illumination, developing and training a reliable classification system and loss of performance due to production variations due to manufacturing tolerances and customer options. This paper describes the measures that have been developed to evaluate the sensitivity of an occupant detection system to these types of variations. Two procedures are described for evaluating how sensitive the classifier is to camera variations. The first procedure is based on classification accuracy while the second evaluates feature differences.

  6. Gamma camera system

    International Nuclear Information System (INIS)

    The invention provides a composite solid state detector for use in deriving a display, by spatial coordinate information, of the distribution or radiation emanating from a source within a region of interest, comprising several solid state detector components, each having a given surface arranged for exposure to impinging radiation and exhibiting discrete interactions therewith at given spatially definable locations. The surface of each component and the surface disposed opposite and substantially parallel thereto are associated with impedence means configured to provide for each opposed surface outputs for signals relating the given location of the interactions with one spatial coordinate parameter of one select directional sense. The detector components are arranged to provide groupings of adjacently disposed surfaces mutually linearly oriented to exhibit a common directional sense of the spatial coordinate parameter. Means interconnect at least two of the outputs associated with each of the surfaces within a given grouping for collecting the signals deriving therefrom. The invention also provides a camera system for imaging the distribution of a source of gamma radiation situated within a region of interest

  7. Proportional counter radiation camera

    Science.gov (United States)

    Borkowski, C.J.; Kopp, M.K.

    1974-01-15

    A gas-filled proportional counter camera that images photon emitting sources is described. A two-dimensional, positionsensitive proportional multiwire counter is provided as the detector. The counter consists of a high- voltage anode screen sandwiched between orthogonally disposed planar arrays of multiple parallel strung, resistively coupled cathode wires. Two terminals from each of the cathode arrays are connected to separate timing circuitry to obtain separate X and Y coordinate signal values from pulse shape measurements to define the position of an event within the counter arrays which may be recorded by various means for data display. The counter is further provided with a linear drift field which effectively enlarges the active gas volume of the counter and constrains the recoil electrons produced from ionizing radiation entering the counter to drift perpendicularly toward the planar detection arrays. A collimator is interposed between a subject to be imaged and the counter to transmit only the radiation from the subject which has a perpendicular trajectory with respect to the planar cathode arrays of the detector. (Official Gazette)

  8. Report on the Radiation Effects Testing of the Infrared and Optical Transition Radiation Camera Systems

    Energy Technology Data Exchange (ETDEWEB)

    Holloway, Michael Andrew [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-04-20

    Presented in this report are the results tests performed at Argonne National Lab in collaboration with Los Alamos National Lab to assess the reliability of the critical 99Mo production facility beam monitoring diagnostics. The main components of the beam monitoring systems are two cameras that will be exposed to radiation during accelerator operation. The purpose of this test is to assess the reliability of the cameras and related optical components when exposed to operational radiation levels. Both X-ray and neutron radiation could potentially damage camera electronics as well as the optical components such as lenses and windows. This report covers results of the testing of component reliability when exposed to X-ray radiation. With the information from this study we provide recommendations for implementing protective measures for the camera systems in order to minimize the occurrence of radiation-induced failure within a ten month production run cycle.

  9. Report on the Radiation Effects Testing of the Infrared and Optical Transition Radiation Camera Systems

    International Nuclear Information System (INIS)

    Presented in this report are the results tests performed at Argonne National Lab in collaboration with Los Alamos National Lab to assess the reliability of the critical 99Mo production facility beam monitoring diagnostics. The main components of the beam monitoring systems are two cameras that will be exposed to radiation during accelerator operation. The purpose of this test is to assess the reliability of the cameras and related optical components when exposed to operational radiation levels. Both X-ray and neutron radiation could potentially damage camera electronics as well as the optical components such as lenses and windows. This report covers results of the testing of component reliability when exposed to X-ray radiation. With the information from this study we provide recommendations for implementing protective measures for the camera systems in order to minimize the occurrence of radiation-induced failure within a ten month production run cycle.

  10. CCD-photometry of comets at large heliocentric distances

    Science.gov (United States)

    Mueller, Beatrice E. A.

    1992-01-01

    CCD imaging and time series photometry are used to determine the state of activity, nuclear properties and eventually the rotational motion of cometary nuclei. Cometary activity at large heliocentric distances and mantle evolution are not yet fully understood. Results of observations carried out at the 2.1 telescope on Kitt Peak April 10-12 and May 15-16, 1991 are discussed. Color values and color-color diagrams are presented for several comets and asteroids. Estimations of nuclear radii and shapes are given.

  11. A 3-channel CCD photometer at the Xinglong Observatory

    International Nuclear Information System (INIS)

    We describe the design and construction of a new rapid 3-channel CCD photometer, dedicated to simultaneous multicolor photometric observations of rapidly variable objects. This photometer is equipped on the 1-meter telescope at the Xinglong Observatory. It allows simultaneous imaging within fields of view of 18.8' × 18.8', 18.2' × 17.6' and 9.2' × 9.2' in the Sloan Digital Sky Survey's g', r' and i' bands, respectively. The results of its calibration and performance are reported.

  12. A 3-channel CCD photometer at the Xinglong Observatory

    Institute of Scientific and Technical Information of China (English)

    Yong-Na Mao; Xiao-Meng Lu; Jian-Feng Wang; Xiao-Jun Jiang

    2013-01-01

    We describe the design and construction of a new rapid 3-channel CCD photometer,dedicated to simultaneous multicolor photometric observations of rapidly variable objects.This photometer is equipped on the 1-meter telescope at the Xinglong Observatory.It allows simultaneous imaging within fields of view of 18.8' × 18.8',18.2' × 17.6' and 9.2' × 9.2' in the Sloan Digital Sky Survey's g',r' and i' bands,respectively.The results of its calibration and performance are reported.

  13. Modelling Gaia CCD pixels with Silvaco 3D engineering software

    CERN Document Server

    Seabroke, G M; Hopkinson, G; Burt, D; Robbins, M; Holland, A

    2010-01-01

    Gaia will only achieve its unprecedented measurement accuracy requirements with detailed calibration and correction for radiation damage. We present our Silvaco 3D engineering software model of the Gaia CCD pixel and two of its applications for Gaia: (1) physically interpreting supplementary buried channel (SBC) capacity measurements (pocket-pumping and first pixel response) in terms of e2v manufacturing doping alignment tolerances; and (2) deriving electron densities within a charge packet as a function of the number of constituent electrons and 3D position within the charge packet as input to microscopic models being developed to simulate radiation damage.

  14. Position-sensitive detection of ultracold neutrons with an imaging camera and its implications to spectroscopy

    CERN Document Server

    Wei, Wanchun; Hoffbauer, M A; Makela, M; Morris, C L; Tang, Z; Adamek, E R; Callahan, N B; Clayton, S M; Cude-Woods, C; Currie, S; Dees, E B; Ding, X; Geltenbort, P; Hickerson, K P; Holley, A T; Ito, T M; Leung, K K; Liu, C -Y; Morley, D J; Ramsey, J C; Pattie,, R W; Salvat, D J; Saunders, A; Seestrom, S J; Sharapov, E I; Sjue, S K; Wexler, J; Womack, T L; Young, A R; Zeck, B A; Wang, Zhehui

    2016-01-01

    Position-sensitive detection of ultracold neutrons (UCNs) is demonstrated using an imaging charge-coupled device (CCD) camera. A spatial resolution less than 15 $\\mu$m has been achieved, which through the relation $\\delta E = m_0g \\delta x$, converts to UCN energy resolution below 2 pico-electron volts. The symbols $\\delta E$, $\\delta x$, $m_0$ and $g$ are for energy resolution, spatial resolution, the neutron rest mass and gravitational acceleration respectively. A multilayer surface convertor described previously is used to capture UCNs and emits visible light for CCD imaging. Particle identification and noise rejection are discussed through light intensity profile analysis. This method allows new types of UCN spectroscopy and various applications.

  15. Position-sensitive detection of ultracold neutrons with an imaging camera and its implications to spectroscopy

    Science.gov (United States)

    Wei, Wanchun; Broussard, L. J.; Hoffbauer, M. A.; Makela, M.; Morris, C. L.; Tang, Z.; Adamek, E. R.; Callahan, N. B.; Clayton, S. M.; Cude-Woods, C.; Currie, S.; Dees, E. B.; Ding, X.; Geltenbort, P.; Hickerson, K. P.; Holley, A. T.; Ito, T. M.; Leung, K. K.; Liu, C.-Y.; Morley, D. J.; Ortiz, Jose D.; Pattie, R. W.; Ramsey, J. C.; Saunders, A.; Seestrom, S. J.; Sharapov, E. I.; Sjue, S. K.; Wexler, J.; Womack, T. L.; Young, A. R.; Zeck, B. A.; Wang, Zhehui

    2016-09-01

    Position-sensitive detection of ultracold neutrons (UCNs) is demonstrated using an imaging charge-coupled device (CCD) camera. A spatial resolution less than 15 μm has been achieved, which is equivalent to a UCN energy resolution below 2 pico-electron-volts through the relation δE =m0 gδx. Here, the symbols δE, δx, m0 and g are the energy resolution, the spatial resolution, the neutron rest mass and the gravitational acceleration, respectively. A multilayer surface convertor described previously is used to capture UCNs and then emits visible light for CCD imaging. Particle identification and noise rejection are discussed through the use of light intensity profile analysis. This method allows different types of UCN spectroscopy and other applications.

  16. The Mars NetLander panoramic camera

    Science.gov (United States)

    Jaumann, Ralf; Langevin, Yves; Hauber, Ernst; Oberst, Jürgen; Grothues, Hans-Georg; Hoffmann, Harald; Soufflot, Alain; Bertaux, Jean-Loup; Dimarellis, Emmanuel; Mottola, Stefano; Bibring, Jean-Pierre; Neukum, Gerhard; Albertz, Jörg; Masson, Philippe; Pinet, Patrick; Lamy, Philippe; Formisano, Vittorio

    2000-10-01

    simultaneous and long-term observations at four different surface locations which becomes especially important for studies of variable surface features as well as properties and phenomena of the atmosphere. Major changes on the surface that can be detected by PanCam are caused by eolian activities and condensation processes, which directly reflect variations in the prevailing near-surface wind regime and the diurnal and seasonal volatile and dust cycles. Atmospheric studies will concentrate on the detection of clouds, measurements of the aerosol contents and the water vapor absorption at 936 nm. In order to meet these objectives, the proposed PanCam instrument is a highly miniaturized, dedicated stereo and multispectral imaging device. The camera consists of two identical camera cubes, which are arranged in a common housing at a fixed stereo base length of 11 cm. Each camera cube is equipped with a CCD frame transfer detector with 1024×1024 active pixels and optics with a focal length of 13 mm yielding a field-of-view of 53°×53° and an instantaneous filed of view of 1.1 mrad. A filter swivel with six positions provides different color band passes in the wavelength range of 400-950 nm. The camera head is mounted on top of a deployable scissors boom and can be rotated by 360° to obtain a full panorama, which is already covered by eight images. The boom raises the camera head to a final altitude of 90 cm above the surface. Most camera activities will take place within the first week and the first month of the mission. During the remainder of the mission, the camera will operate with a reduced data rate to monitor time-dependent variations on a daily basis. PanCam is a joint German/French project with contributions from DLR, Institute of Space Sensor Technology and Planetary Exploration, Berlin, Institut d'Astrophysique Spatiale, CNRS, Orsay, and Service d'Aéronomie, CNRS, Verrières-le-Buisson.

  17. The Fourth US Naval Observatory CCD Astrograph Catalog (UCAC4)

    CERN Document Server

    Zacharias, Norbert; Girard, Terry; Henden, Arne; Bartlett, Jennifer; Monet, Dave; Zacharias, Marion

    2012-01-01

    The fourth United States Naval Observatory (USNO) CCD Astrograph Catalog, UCAC4 was released in August 2012 (double-sided DVD and CDS data center Vizier catalog I/322). It is the final release in this series and contains over 113 million objects; over 105 million of them with proper motions. UCAC4 is an updated version of UCAC3 with about the same number of stars also covering all-sky. Bugs were fixed, Schmidt plate survey data were avoided, and precise 5-band photometry were added. Astrograph observations have been supplemented for bright stars by FK6, Hipparcos and Tycho-2 data to compile a UCAC4 star catalog complete to about magnitude R = 16. Epoch 1998 to 2004 positions are obtained from observations with the 20 cm aperture USNO Astrograph's red lens, equipped with a 4k by 4k CCD. Mean positions and proper motions are derived by combining these observations with over 140 ground- and space-based catalogs, including Hipparcos/Tycho and the AC2000.2, as well as unpublished measures of over 5000 plates from ...

  18. CCD Photometric Study and Period Investigation of AH Tauri

    Science.gov (United States)

    Xiang, Fu-Yuan; Xiao, Ting-Yu; Yu, Yun-Xia

    2015-07-01

    In this paper, we present new CCD photometric observations of AH Tauri in the R band observed in 2006 at the Yunnan Observatory. Two new times of light minima were derived from these observations. We modeled the light curves using the 2003 version of the Wilson-Devinney program. The results show that the variations of the light curves can be expained by a cool spot on the primary star. The fill-out factor is about 6.6%, indicating that AH Tauri is a shallow-contact system. The mass ratio was determined to be about 0.505. In addition, the orbital period variations of AH Tauri were investigated based on all of the photoelectric and CCD light minimum times, including our two new data. It was found that the orbital period exhibits a possible periodic variation with a period of {P}{mod}=54.62\\(+/- 0.20) years and a secular period decrease of {dP}/{dt}=-(1.823+/- 0.215)× {10}-7 {days} {{yr}}-1. Since AH Tauri is an overcontact solar-like system, we discuss three mechanisms of the mass transfer, the light-time effect of the third body, and magnetic activity responsible for the orbital period changes.

  19. Wide field CCD photometry of the globular cluster M92

    CERN Document Server

    Lee, K H; Fahlman, G G; Lee, M G; Lee, Kang Hwan; Lee, Hyung Mok; Fahlman, Gregory G.; Lee, Myung Gyoon

    2003-01-01

    We present wide field CCD photometry of a galactic globular cluster M92 obtained in the V and I bands with the CFH12K mosaic CCD at the Canada-France-Hawaii Telescope. A well-defined color-magnitude diagram is derived down to 5 magnitudes fainter than the cluster main sequence turn-off. After removing the background contribution, we obtain luminosity and mass functions, surface density profiles, and the surface number density maps of the stars belonging to the cluster. The surface density profile of all stars shows that the cluster's halo extends at least out to ~30' from the cluster center in agreement with previous study, but the profile of faint stars at the very outer region of the cluster shows a different gradient compared with that of bright stars. For a mass function of the cluster, we find that the inner region of the cluster has x = 1.2+-0.2, whereas the outer region has x = 1.8 +-0.3, clearly indicating a mass segregation of the cluster. An estimate of the photometric mass of the cluster implies th...

  20. The Calibration of High-Speed Camera Imaging System for ELMs Observation on EAST Tokamak

    Science.gov (United States)

    Fu, Chao; Zhong, Fangchuan; Hu, Liqun; Yang, Jianhua; Yang, Zhendong; Gan, Kaifu; Zhang, Bin; East Team

    2016-09-01

    A tangential fast visible camera has been set up in EAST tokamak for the study of edge MHD instabilities such as ELM. To determine the 3-D information from CCD images, Tsai's two-stage technique was utilized to calibrate the high-speed camera imaging system for ELM study. By applying tiles of the passive stabilizers in the tokamak device as the calibration pattern, transformation parameters for transforming from a 3-D world coordinate system to a 2-D image coordinate system were obtained, including the rotation matrix, the translation vector, the focal length and the lens distortion. The calibration errors were estimated and the results indicate the reliability of the method used for the camera imaging system. Through the calibration, some information about ELM filaments, such as positions and velocities were obtained from images of H-mode CCD videos. supported by National Natural Science Foundation of China (No. 11275047), the National Magnetic Confinement Fusion Science Program of China (No. 2013GB102000)

  1. Performance of a direct detection camera for off-axis electron holography.

    Science.gov (United States)

    Chang, Shery L Y; Dwyer, Christian; Barthel, Juri; Boothroyd, Chris B; Dunin-Borkowski, Rafal E

    2016-02-01

    The performance of a direct detection camera (DDC) is evaluated in the context of off-axis electron holographic experiments in a transmission electron microscope. Its performance is also compared directly with that of a conventional charge-coupled device (CCD) camera. The DDC evaluated here can be operated either by the detection of individual electron events (counting mode) or by the effective integration of many such events during a given exposure time (linear mode). It is demonstrated that the improved modulation transfer functions and detective quantum efficiencies of both modes of the DDC give rise to significant benefits over the conventional CCD cameras, specifically, a significant improvement in the visibility of the holographic fringes and a reduction of the statistical error in the phase of the reconstructed electron wave function. The DDC's linear mode, which can handle higher dose rates, allows optimisation of the dose rate to achieve the best phase resolution for a wide variety of experimental conditions. For suitable conditions, the counting mode can potentially utilise a significantly lower dose to achieve a phase resolution that is comparable to that achieved using the linear mode. The use of multiple holograms and correlation techniques to increase the total dose in counting mode is also demonstrated. PMID:26630072

  2. Photon counting imaging with an electron-bombarded CCD: Towards a parallel-processing photoelectronic time-to-amplitude converter

    Energy Technology Data Exchange (ETDEWEB)

    Hirvonen, Liisa M.; Jiggins, Stephen; Sergent, Nicolas; Zanda, Gianmarco; Suhling, Klaus, E-mail: klaus.suhling@kcl.ac.uk [Department of Physics, King' s College London, Strand, London WC2R 2LS (United Kingdom)

    2014-12-15

    We have used an electron-bombarded CCD for optical photon counting imaging. The photon event pulse height distribution was found to be linearly dependent on the gain voltage. We propose on this basis that a gain voltage sweep during exposure in an electron-bombarded sensor would allow photon arrival time determination with sub-frame exposure time resolution. This effectively uses an electron-bombarded sensor as a parallel-processing photoelectronic time-to-amplitude converter, or a two-dimensional photon counting streak camera. Several applications that require timing of photon arrival, including Fluorescence Lifetime Imaging Microscopy, may benefit from such an approach. A simulation of a voltage sweep performed with experimental data collected with different acceleration voltages validates the principle of this approach. Moreover, photon event centroiding was performed and a hybrid 50% Gaussian/Centre of Gravity + 50% Hyperbolic cosine centroiding algorithm was found to yield the lowest fixed pattern noise. Finally, the camera was mounted on a fluorescence microscope to image F-actin filaments stained with the fluorescent dye Alexa 488 in fixed cells.

  3. Proton irradiation test to scintillator-directory-coupled CCD onboard FFAST

    Science.gov (United States)

    Nagino, Ryo; Nakajima, Hiroshi; Sadamoto, Masaaki; Sasaki, Masayuki; Tsunemi, Hiroshi; Hayashida, Kiyoshi; Anabuki, Naohisa; Kitamura, Hisashi; Uchihori, Yukio

    2013-09-01

    FFAST is a large area sky survey mission at hard X-ray region by using a spacecraft formation flying. It consists of two small satellites, a telescope satellite, carrying a multilayer super mirror, and a detector satellite, carrying scintillator-deposited CCDs (SD-CCDs). SD-CCD is the imaging device which realized sensitivity to 80 keV by pasting up a scintillator on CCD directly. Soft X-ray events are directly detected in the CCD. On the other hand, Hard X-ray events are converted to optical photons by the scintillator and then the CCD detects the photons. We have obtained the spectrum with 109Cd and successfully detected the events originated from the CsI. For a space use of a CCD, we have to understand aged deterioration of CCD in high radiative environments. In addition, in the case of SD-CCD, we must investigate the influence of radio-activation of a scintillator. We performed experiments of proton irradiation to the SD-CCD as space environmental tests of cosmic rays. The SD-CCD is irradiated with the protons with the energy of 100 MeV and neglected for about 150 hours. As a result, the derived CTI profile of SD-CCD is similarly to ones of XIS/Suzaku and NeXT4 CCD/ASTRO-H. In contrast, CTIs derived from the data within 4 hours after irradiation is 10 times or more larger than the ones after 150 hours. This may be due to influence of an annealing. We also report a performance study of SD-CCD, including the detection of scintillation events, before proton irradiation.

  4. An Inexpensive Digital Infrared Camera

    Science.gov (United States)

    Mills, Allan

    2012-01-01

    Details are given for the conversion of an inexpensive webcam to a camera specifically sensitive to the near infrared (700-1000 nm). Some experiments and practical applications are suggested and illustrated. (Contains 9 figures.)

  5. The future of consumer cameras

    Science.gov (United States)

    Battiato, Sebastiano; Moltisanti, Marco

    2015-03-01

    In the last two decades multimedia, and in particular imaging devices (camcorders, tablets, mobile phones, etc.) have been dramatically diffused. Moreover the increasing of their computational performances, combined with an higher storage capability, allows them to process large amount of data. In this paper an overview of the current trends of consumer cameras market and technology will be given, providing also some details about the recent past (from Digital Still Camera up today) and forthcoming key issues.

  6. A CCD-based fluorescence imaging system for real-time loop-mediated isothermal amplification-based rapid and sensitive detection of waterborne pathogens on microchips.

    Science.gov (United States)

    Ahmad, Farhan; Seyrig, Gregoire; Tourlousse, Dieter M; Stedtfeld, Robert D; Tiedje, James M; Hashsham, Syed A

    2011-10-01

    Rapid, sensitive, and low-cost pathogen diagnostic systems are needed for early disease diagnosis and treatment, especially in resource-limited settings. This study reports a low-cost charge-coupled device (CCD)-based fluorescence imaging system for rapid detection of waterborne pathogens by isothermal gene amplification in disposable microchips. Fluorescence imaging capability of this monochromatic CCD camera is evaluated by optimizing the gain, offset, and exposure time. This imaging system is validated for 12 virulence genes of major waterborne pathogens on cyclic olefin polymer (COP) microchips, using SYTO-82 dye and real time fluorescence loop-mediated isothermal amplification referred here as microRT(f)-LAMP. Signal-to-noise ratio (SNR) and threshold time (Tt) of microRT(f)-LAMP assays are compared with those from a commercial real-time polymerase chain reaction (PCR) instrument. Applying a CCD exposure of 5 s to 10(5) starting DNA copies of microRT(f)-LAMP assays increases the SNR by 8-fold and reduces the Tt by 9.8 min in comparison to a commercial real-time PCR instrument. Additionally, single copy level sensitivity for Campylobacter jejuni 0414 gene is obtained for microRT(f)-LAMP with a Tt of 19 min, which is half the time of the commercial real-time PCR instrument. Due to the control over the exposure time and the wide field imaging capability of CCD, this low-cost fluorescence imaging system has the potential for rapid and parallel detection of pathogenic microorganisms in high throughput microfluidic chips.

  7. Jpcam: a 1.2 Gpixel Camera for the J-Pas Survey

    Science.gov (United States)

    Taylor, K.; Marín-Franch, A.; Laporte, R.; Santoro, F. G.; Marrara, L.; Cepa, J.; Cenarro, A. J.; Chueca, S.; Cristobal-Hornillos, D.; Ederoclite, A.; Gruel, N.; Moles, M.; Rueda, F.; Rueda, S.; Varela, J.; Yanes, A.; Benitez, N.; Dupke, R.; Fernández-Soto, A.; Jorden, P.; Lousberg, G.; Molino Benito, A.; Palmer, I.; Mendes de Oliveira, C.; Sodré, L.

    JPCam is a 14-CCD mosaic camera, using the new e2v 9k-by-9k 10 μm-pixel 16-channel detectors, to be deployed on a dedicated 2.55 m wide-field telescope at the OAJ (Observatorio Astrofísico de Javalambre) in Aragon, Spain. The camera is designed to perform a Baryon Acoustic Oscillations (BAO) survey of the northern sky. The J-PAS survey strategy will use 54 relatively narrow-band ( 13.8 nm) filters equi-spaced between 370 and 920 nm plus 3 broad-band filters to achieve unprecedented photometric red-shift accuracies for faint galaxies over 8000 square degrees of sky. The cryostat, detector mosaic and read electronics, is being supplied by e2v under contract to J-PAS while the mechanical structure, housing the shutter and filter assembly, is being designed and constructed by a Brazilian consortium led by INPE (Instituto Nacional de Pesquisas Espaciais). The cryostat is bridged to the telescope via a hexapod actuator system to maintain image quality across the field. Four sets of 14 filters are placed in the ambient environment, just above the dewar window but directly in line with the detectors, leading to a mosaic having 10 mm gaps between each CCD. The massive 500 mm aperture shutter is expected to be supplied by the Bonn-Shutter UG. We will present an overview of JPCam, from the filter configuration through to the CCD mosaic camera. A brief outline of the main J-PAS science projects will be included.

  8. JPCam: Status of the 1.2Gpixel camera for the J-PAS survey.

    Science.gov (United States)

    Taylor, Keith; Marín-Franch, Antonio; Santoro, Fernando; Mendes de Oliveira, Claudia; Dupke, Renato

    2015-08-01

    JPCam is a 14-CCD mosaic camera, using the new e2v 9k-by-9k, 10 micron pixel detectors, to be deployed on the JST/T250, a dedicated 2.55m wide-field telescope at the OAJ (Observatorio Astrofísico de Javalambre) in Teruel, Spain. The camera is designed to perform the J-PAS, a BAO survey of the northern sky. The J-PAS survey strategy will use 59 filters, 56 relatively narrow-band (14.5nm) filters equi-spaced between 350 and 1000nm plus 3 broad-band filters to achieve unprecedented photometric red-shift accuracies for faint galaxies over 8000 square degrees of sky. The cryostat, detector mosaic and read electronics is being supplied by e2v. Each science detector is read from 16 ports simultaneously, allowing read times of 14s with a typical read noise of 5e- (rms). The JPCam focal plane will be complemented with 4 autoguiding and 8 wavefront sensing CCDs. Image quality over the whole CCD mosaic will be maintained by applying the required, close loop, focus, tilt and rotation adjustments to the focal plane through the JPCam hexapod actuator system, manufactured by NTE-Sener. The filter unit has been designed to admit 5 filter trays, each mounting 14 filters corresponding to the 14 CCDs of the mosaic. Each CCD will view only its corresponding filter avoiding optical cross-talk from their neighbors. With this configuration, JPCam will cover 4.7 square degrees with a plate scale of 0.2267 arcsec/pix and will allow all the J-PAS filters to be permanently installed on the camera. The massive 525mm aperture shutter is supplied by Bonn-Shutter UG.

  9. Derivation of Johnson-Cousins Magnitudes from DSLR Camera Observations

    Science.gov (United States)

    Park, Woojin; Pak, Soojong; Shim, Hyunjin; Le, Huynh Anh N.; Im, Myungshin; Chang, Seunghyuk; Yu, Joonkyu

    2016-01-01

    The RGB Bayer filter system consists of a mosaic of R, G, and B filters on the grid of the photo sensors which typical commercial DSLR (Digital Single Lens Reflex) cameras and CCD cameras are equipped with. Lot of unique astronomical data obtained using an RGB Bayer filter system are available, including transient objects, e.g. supernovae, variable stars, and solar system bodies. The utilization of such data in scientific research requires that reliable photometric transformation methods are available between the systems. In this work, we develop a series of equations to convert the observed magnitudes in the RGB Bayer filter system (RB, GB, and BB) into the Johnson-Cousins BVR filter system (BJ, VJ, and RC). The new transformation equations derive the calculated magnitudes in the Johnson-Cousins filters (BJcal, VJcal, and RCcal) as functions of RGB magnitudes and colors. The mean differences between the transformed magnitudes and original magnitudes, i.e. the residuals, are (BJ - BJcal) = 0.064 mag, (VJ - VJcal) = 0.041 mag, and (RC - RCcal) = 0.039 mag. The calculated Johnson-Cousins magnitudes from the transformation equations show a good linear correlation with the observed Johnson-Cousins magnitudes.

  10. On the absolute calibration of SO2 cameras

    Science.gov (United States)

    Lübcke, Peter; Bobrowski, Nicole; Illing, Sebastian; Kern, Christoph; Alvarez Nieves, Jose Manuel; Vogel, Leif; Zielcke, Johannes; Delgados Granados, Hugo; Platt, Ulrich

    2013-01-01

    Sulphur dioxide emission rate measurements are an important tool for volcanic monitoring and eruption risk assessment. The SO2 camera technique remotely measures volcanic emissions by analysing the ultraviolet absorption of SO2 in a narrow spectral window between 300 and 320 nm using solar radiation scattered in the atmosphere. The SO2 absorption is selectively detected by mounting band-pass interference filters in front of a two-dimensional, UV-sensitive CCD detector. One important step for correct SO2 emission rate measurements that can be compared with other measurement techniques is a correct calibration. This requires conversion from the measured optical density to the desired SO2 column density (CD). The conversion factor is most commonly determined by inserting quartz cells (cuvettes) with known amounts of SO2 into the light path. Another calibration method uses an additional narrow field-of-view Differential Optical Absorption Spectroscopy system (NFOVDOAS), which measures the column density simultaneously in a small area of the camera’s field-of-view. This procedure combines the very good spatial and temporal resolution of the SO2 camera technique with the more accurate column densities obtainable from DOAS measurements.

  11. Position-sensitive detection of ultracold neutrons with an imaging camera and its implications to spectroscopy

    OpenAIRE

    Wei, Wanchun; Broussard, L. J.; Hoffbauer, M. A.; Makela, M.; Morris, C. L.; Tang, Z.(University of Science & Technology of China, Hefei, 230026, China); Adamek, E. R.; Callahan, N. B.; Clayton, S. M.; Cude-Woods, C.; Currie, S; Dees, E. B.; Ding, X; Geltenbort, P.(Institut Laue-Langevin, Grenoble Cedex 9, 38042, France); Hickerson, K. P.

    2016-01-01

    Position-sensitive detection of ultracold neutrons (UCNs) is demonstrated using an imaging charge-coupled device (CCD) camera. A spatial resolution less than 15 $\\mu$m has been achieved, which is equivalent to an UCN energy resolution below 2 pico-electron-volts through the relation $\\delta E = m_0g \\delta x$. Here, the symbols $\\delta E$, $\\delta x$, $m_0$ and $g$ are the energy resolution, the spatial resolution, the neutron rest mass and the gravitational acceleration, respectively. A mult...

  12. A low-cost, CCD solid state star tracker

    Science.gov (United States)

    Chmielowski, M.; Wynne, D.

    1992-01-01

    Applied Research Corporation (ARC) has developed an engineering model of a multi-star CCD-based tracker for space applications requiring radiation hardness, high reliability and low power consumption. The engineering unit compared favorably in functional performance tests to the standard NASA single-star tracker. Characteristics of the ARC star tracker are: field of view = 10 deg x 7.5 deg, sensitivity range of -1 to +5 star magnitude, NEA = 3 in x 3 in, linearity = 5 in x 5 in, and power consumption of 1-3 W (operating mode dependent). The software is upgradable through a remote link. The hardware-limited acquisition rate is 1-5 Hz for stars of +2 to +5 magnitude and 10-30 Hz for -1 to +2 magnitude stars. Mechanical and electrical interfaces are identical to the standard NASA star tracker.

  13. A tasseled cap transformation for CBERS-02B CCD data

    Institute of Scientific and Technical Information of China (English)

    Li SHENG; Jing-feng HUANG; Xiao-lu TANG

    2011-01-01

    The tasseled cap transformation of remote sensing data has been widely used in agriculture,forest,ecology,and landscape.In this paper,tasseled cap transformation coefficients appropriate for data from a new sensor (China & Brazil Earth Resource Satellite (CBERS-02B)) are presented.The first three components after transformation captured 98% of the four-band variance,and represent the physical characteristics of brightness (coefficients:0.509,0.431,0.330,and 0.668),greenness (coefficients:-0.494,-0.318,-0.324,and 0.741),and blueness (coefficients:0.581,-0.070,-0.811,and 0.003),respectively.We hope these results will enhance the application of CBERS-02B charge-coupled device (CCD) data in the areas of agriculture,forest,ecology,and landscape.

  14. CCD $UBV(RI)_{C}$ Photometry of Twenty Open Clusters

    CERN Document Server

    Oralhan, Inci Akkaya; Schuster, William J; Michel, Raúl; Chavarría, Carlos

    2014-01-01

    Fundamental astrophysical parameters have been derived for 20 open clusters (O\\!Cs) using CCD~$U\\!BV\\!(RI)_C$ photometric data observed with the 84~cm telescope at the San Pedro M\\'artir National Astronomical Observatory, M\\'exico. The interstellar reddenings, metallicities, distances, and ages have been compared to the literature values. Significant differences are usually due to the usage of diverse empirical calibrations and differing assumptions, such as concerning cluster metallicity, as well as distinct isochrones which correspond to differing element-abundance ratios, internal stellar physics, and photometric systems. Different interstellar reddenings, as well as varying reduction and cluster-membership techniques, are also responsible for these kinds of systematic differences and errors. The morphological ages, which are derived from the morphological indices ($\\delta V$ and $\\delta 1$) in the CM diagrams, are in good agreement with the isochrone ages of 12 O\\!Cs, those with good red clump (RC) and re...

  15. CCD development for the Dark Energy Spectroscopic Instrument

    International Nuclear Information System (INIS)

    We describe research and development efforts directed towards the production of 4 k × 4 k, 15 μm-pixel, fully depleted CCDs for the Dark Energy Spectroscopic Instrument (DESI). The requirements for DESI include the spectroscopic characterization of large numbers of faint galaxies at high redshift. The identification of the type and the determination of the redshift of the targeted galaxies require the use of thick, fully depleted CCDs with high quantum efficiency at near-infrared wavelengths. We describe our work to improve the CCD performance in terms of quantum efficiency and read noise. We also discuss efforts to reduce the level of image-distortion effects that have been observed on previous CCDs that are due to resistivity striations in the starting silicon and periodic errors in the photomasks used to produce the CCDs

  16. Large area CCD image sensors for scientific applications

    Science.gov (United States)

    Blouke, M. M.; Heidtmann, D. L.; Corrie, B.; Lust, M. L.; Janesick, J. R.

    1985-01-01

    The designs of the 512 x 512 pixel and 2048 x 2048 pixel CCD sensors developed for scientific imaging are described. Both sensors are manufactured using the three phase, three level polysilicon gate technology, and the architecture of the chips is series-parallel-series. The components of the two different on-chip amplifiers are examined. The sensors are thinned and operated in the back side illumination mode to ensure the highest quantum efficiency. The performances of a number of front side illuminated devices and two thinned rear illuminated chips are evaluated. It is observed that the sensors equal or exceed their proposed charge transfer efficiency of 0.99999, the noise level of 2 e- and 20 e- at 50 kp/s, the quantum efficiency of 40 percent at 400 microns and 70 percent at 700 microns, and of the well capacity of greater than 500 ke-/pixel.

  17. CCD-based optical CT scanning of highly attenuating phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Al-Nowais, Shamsa [Department of Physics, University of Surrey, Guildford (United Kingdom); Doran, Simon J [CRUK Clinical MR Research Group, Institute of Cancer Research, Sutton (United Kingdom)], E-mail: Simon.Doran@icr.ac.uk

    2009-05-01

    The introduction of optical computed tomography (optical-CT) offers economic and easy to use 3-D optical readout for gel dosimeters. However, previous authors have noted some challenges regarding the accuracy of such imaging techniques at high values of optical density. In this paper, we take a closer look at the 'cupping' artefact evident in both light-scattering polymer systems and highly light absorbing phantoms using our CCD-based optical scanner. In addition, a technique is implemented whereby the maximum measurable optical absorbance is extended to correct for any errors that may have occurred in the estimated value of the dark current or ambient light reaching the detector. The results indicate that for absorbance values up to 2.0, the optical scanner results have good accuracy, whereas this is not the case at high absorbance values for reasons yet to be explained.

  18. Fifteen years of the Advanced CCD Imaging Spectrometer

    CERN Document Server

    Grant, Catherine E; Ford, Peter G; Plucinsky, Paul P

    2014-01-01

    As the Advanced CCD Imaging Spectrometer (ACIS) on the Chandra X-ray Observatory enters its fifteenth year of operation on orbit, it continues to perform well and produce spectacular scientific results. The response of ACIS has evolved over the lifetime of the observatory due to radiation damage, molecular contamination and aging of the spacecraft in general. Here we present highlights from the instrument team's monitoring program and our expectations for the future of ACIS. The ACIS calibration source produces multiple line energies and fully illuminates the entire focal plane which has greatly facilitated the measurement of charge transfer inefficiency and absorption from contamination. While the radioactive decay of the source has decreased its utility, it continues to provide valuable data on the health of the instrument. Performance changes on ACIS continue to be manageable, and do not indicate any limitations on ACIS lifetime.

  19. Optimal CCD readout by digital correlated double sampling

    CERN Document Server

    Alessandri, Cristobal; Guzman, Dani; Passalacqua, Ignacio; Alvarez-Fontecilla, Enrique; Guarini, Marcelo

    2015-01-01

    Digital correlated double sampling (DCDS), a readout technique for charge-coupled devices (CCD), is gaining popularity in astronomical applications. By using an oversampling ADC and a digital filter, a DCDS system can achieve a better performance than traditional analogue readout techniques at the expense of a more complex system analysis. Several attempts to analyse and optimize a DCDS system have been reported, but most of the work presented in the literature has been experimental. Some approximate analytical tools have been presented for independent parameters of the system, but the overall performance and trade-offs have not been yet modelled. Furthermore, there is disagreement among experimental results that cannot be explained by the analytical tools available. In this work, a theoretical analysis of a generic DCDS readout system is presented, including key aspects such as the signal conditioning stage, the ADC resolution, the sampling frequency and the digital filter implementation. By using a time-dom...

  20. Clinical ultraviolet dosimetry with a CCD monochromator array spectroradiometer

    Science.gov (United States)

    Coleman, Andrew; Sarkany, Robert; Walker, Susan

    2008-09-01

    Single monochromator charge-coupled device (CCD) array spectroradiometers have the advantage of ease of use and speed compared with double grating instruments. Their inherently inferior stray-light rejection, however, can critically affect their accuracy in phototherapy and research-related dosimetry applications. This paper shows that without adequate correction the HR4000 (Ocean Optics Inc., Dunedin, USA) array device can overestimate the CIE erythema-weighted irradiance of common phototherapy sources and solar simulator beams by over 100%. A software stray-light correction (Ylianttila et al 2005 Photochem. Photobiol. 81 333-41), using the measured slit function of the HR4000, has been applied to spectra acquired from sources used in phototherapy and photobiology (PUVA, UV21, TL01 and solar simulator). The resulting corrected erythema-weighted irradiance measurements from the HR4000 are within 10% of those from a DM150 double grating spectroradiometer (Bentham Instruments Ltd, Reading, UK). A simple model is considered for combining estimates of measurement uncertainties. The importance of exposure bracketing to improve the dynamic range of the HR4000 is illustrated, along with the difficulty in making direct comparison of spectral values between two instruments due to wavelength scale uncertainties. Comparison with a double grating instrument in a solar simulator beam is examined here as a basis for validating CCD array device measurements. The study demonstrates that the HR4000 array spectroradiometer can provide an adequate level of accuracy for common phototherapy and photobiology applications only where a suitable stray-light correction is carefully applied and where the instrument's effective dynamic range is improved.

  1. Optimal CCD readout by digital correlated double sampling

    Science.gov (United States)

    Alessandri, C.; Abusleme, A.; Guzman, D.; Passalacqua, I.; Alvarez-Fontecilla, E.; Guarini, M.

    2016-01-01

    Digital correlated double sampling (DCDS), a readout technique for charge-coupled devices (CCD), is gaining popularity in astronomical applications. By using an oversampling ADC and a digital filter, a DCDS system can achieve a better performance than traditional analogue readout techniques at the expense of a more complex system analysis. Several attempts to analyse and optimize a DCDS system have been reported, but most of the work presented in the literature has been experimental. Some approximate analytical tools have been presented for independent parameters of the system, but the overall performance and trade-offs have not been yet modelled. Furthermore, there is disagreement among experimental results that cannot be explained by the analytical tools available. In this work, a theoretical analysis of a generic DCDS readout system is presented, including key aspects such as the signal conditioning stage, the ADC resolution, the sampling frequency and the digital filter implementation. By using a time-domain noise model, the effect of the digital filter is properly modelled as a discrete-time process, thus avoiding the imprecision of continuous-time approximations that have been used so far. As a result, an accurate, closed-form expression for the signal-to-noise ratio at the output of the readout system is reached. This expression can be easily optimized in order to meet a set of specifications for a given CCD, thus providing a systematic design methodology for an optimal readout system. Simulated results are presented to validate the theory, obtained with both time- and frequency-domain noise generation models for completeness.

  2. Three-dimensional location and attitude evaluation for rendezvous and docking operation using a single camera

    Science.gov (United States)

    Wang, Zhiling; Losito, S.; Mugnuolo, Raffaele; Pasquariello, Guido

    1993-01-01

    In the automatic rendezvous and docking manoeuvre (RVD) of space activity, determining the 3-D location and attitude between two vehicles is most important. A vision system to perform the docking manipulation in RVD is described in this paper. An improved algorithm is used for calibrating the geometric parameters of a camera fixed on the tracking vehicle off-line. Because the line-off-sight angles of four markers on the target vehicle to the lens center of the camera can be computed according to the optical principle and vector theory, the locations of the vehicle are obtained from the solution for a set of nonlinear equations from the triangular theory. The attitude angles for the vehicles are solved by a translational matrix of target frame to vehicle frame. As the vehicle closes in to the target, sets of markers having different distance intervals or a list of calibration parameters for cameras with different fields of view are selected at the proper moment to improve the situation when at least one of the markers exceeds the field of camera view. The series of experiments is given. The vision system is run on a SUN-4/330 Sparc station system equipped with one image board IT-151 and a CCD TV camera. All software is written in C language.

  3. New Sensors for Cultural Heritage Metric Survey: The ToF Cameras

    Directory of Open Access Journals (Sweden)

    Filiberto Chiabrando

    2011-12-01

    Full Text Available ToF cameras are new instruments based on CCD/CMOS sensors which measure distances instead of radiometry. The resulting point clouds show the same properties (both in terms of accuracy and resolution of the point clouds acquired by means of traditional LiDAR devices. ToF cameras are cheap instruments (less than 10.000 € based on video real time distance measurements and can represent an interesting alternative to the more expensive LiDAR instruments. In addition, the limited weight and dimensions of ToF cameras allow a reduction of some practical problems such as transportation and on-site management. Most of the commercial ToF cameras use the phase-shift method to measure distances. Due to the use of only one wavelength, most of them have limited range of application (usually about 5 or 10 m. After a brief description of the main characteristics of these instruments, this paper explains and comments the results of the first experimental applications of ToF cameras in Cultural Heritage 3D metric survey.  The possibility to acquire more than 30 frames/s and future developments of these devices in terms of use of more than one wavelength to overcome the ambiguity problem allow to foresee new interesting applications.

  4. Real-time registration compensator for 1-inch Harpicon Hi-Vision camera

    Science.gov (United States)

    Mimura, Itaru; Tomura, Naoto; Murata, Nobuo; Ohoka, Masaharu

    1992-08-01

    We have developed a real-time registration compensator for 1" Harpicon the Hi-Vision camera. Harpicon has the advantages of higher sensitivity and higher resolution than Saticon or Hi-Vision CCD imagers. However a camera with image pick-up tubes such as Harpicon produces registration errors which causes lower resolution and false color on objective edges. To solve this problem we developed a new method of detecting registration errors which is suitable for digital Hi-Vision cameras. The detector finds registration errors in the picture during the camera operation. This frees the operator from initial registration tuning and enables real-time compensation. Recently we developed a detection large scale integrated (LSI) circuit with a 1. 3tm complemental metal-oxide semi-conductor (CMOS) gate array and implemented the system in hardware. The detection hardware consists of two gate arrays twenty-four 256k x 4-bit FIFO memories and a small amount of control logic. The experimental hardware detects registration errors at 30 points (5 points vertically and 6 horizontally) in both R-G and B-G channels within 700 msec. The camera has a high resolution (40

  5. SUB-CAMERA CALIBRATION OF A PENTA-CAMERA

    Directory of Open Access Journals (Sweden)

    K. Jacobsen

    2016-03-01

    Full Text Available Penta cameras consisting of a nadir and four inclined cameras are becoming more and more popular, having the advantage of imaging also facades in built up areas from four directions. Such system cameras require a boresight calibration of the geometric relation of the cameras to each other, but also a calibration of the sub-cameras. Based on data sets of the ISPRS/EuroSDR benchmark for multi platform photogrammetry the inner orientation of the used IGI Penta DigiCAM has been analyzed. The required image coordinates of the blocks Dortmund and Zeche Zollern have been determined by Pix4Dmapper and have been independently adjusted and analyzed by program system BLUH. With 4.1 million image points in 314 images respectively 3.9 million image points in 248 images a dense matching was provided by Pix4Dmapper. With up to 19 respectively 29 images per object point the images are well connected, nevertheless the high number of images per object point are concentrated to the block centres while the inclined images outside the block centre are satisfying but not very strongly connected. This leads to very high values for the Student test (T-test of the finally used additional parameters or in other words, additional parameters are highly significant. The estimated radial symmetric distortion of the nadir sub-camera corresponds to the laboratory calibration of IGI, but there are still radial symmetric distortions also for the inclined cameras with a size exceeding 5μm even if mentioned as negligible based on the laboratory calibration. Radial and tangential effects of the image corners are limited but still available. Remarkable angular affine systematic image errors can be seen especially in the block Zeche Zollern. Such deformations are unusual for digital matrix cameras, but it can be caused by the correlation between inner and exterior orientation if only parallel flight lines are used. With exception of the angular affinity the systematic image errors

  6. The Clementine longwave infrared camera

    Energy Technology Data Exchange (ETDEWEB)

    Priest, R.E.; Lewis, I.T.; Sewall, N.R.; Park, H.S.; Shannon, M.J.; Ledebuhr, A.G.; Pleasance, L.D. [Lawrence Livermore National Lab., CA (United States); Massie, M.A. [Pacific Advanced Technology, Solvang, CA (United States); Metschuleit, K. [Amber/A Raytheon Co., Goleta, CA (United States)

    1995-04-01

    The Clementine mission provided the first ever complete, systematic surface mapping of the moon from the ultra-violet to the near-infrared regions. More than 1.7 million images of the moon, earth and space were returned from this mission. The longwave-infrared (LWIR) camera supplemented the UV/Visible and near-infrared mapping cameras providing limited strip coverage of the moon, giving insight to the thermal properties of the soils. This camera provided {approximately}100 m spatial resolution at 400 km periselene, and a 7 km across-track swath. This 2.1 kg camera using a 128 x 128 Mercury-Cadmium-Telluride (MCT) FPA viewed thermal emission of the lunar surface and lunar horizon in the 8.0 to 9.5 {micro}m wavelength region. A description of this light-weight, low power LWIR camera along with a summary of lessons learned is presented. Design goals and preliminary on-orbit performance estimates are addressed in terms of meeting the mission`s primary objective for flight qualifying the sensors for future Department of Defense flights.

  7. Laser guide star pointing camera for ESO LGS Facilities

    Science.gov (United States)

    Bonaccini Calia, D.; Centrone, M.; Pedichini, F.; Ricciardi, A.; Cerruto, A.; Ambrosino, F.

    2014-08-01

    Every observatory using LGS-AO routinely has the experience of the long time needed to bring and acquire the laser guide star in the wavefront sensor field of view. This is mostly due to the difficulty of creating LGS pointing models, because of the opto-mechanical flexures and hysteresis in the launch and receiver telescope structures. The launch telescopes are normally sitting on the mechanical structure of the larger receiver telescope. The LGS acquisition time is even longer in case of multiple LGS systems. In this framework the optimization of the LGS systems absolute pointing accuracy is relevant to boost the time efficiency of both science and technical observations. In this paper we show the rationale, the design and the feasibility tests of a LGS Pointing Camera (LPC), which has been conceived for the VLT Adaptive Optics Facility 4LGSF project. The LPC would assist in pointing the four LGS, while the VLT is doing the initial active optics cycles to adjust its own optics on a natural star target, after a preset. The LPC allows minimizing the needed accuracy for LGS pointing model calibrations, while allowing to reach sub-arcsec LGS absolute pointing accuracy. This considerably reduces the LGS acquisition time and observations operation overheads. The LPC is a smart CCD camera, fed by a 150mm diameter aperture of a Maksutov telescope, mounted on the top ring of the VLT UT4, running Linux and acting as server for the client 4LGSF. The smart camera is able to recognize within few seconds the sky field using astrometric software, determining the stars and the LGS absolute positions. Upon request it returns the offsets to give to the LGS, to position them at the required sky coordinates. As byproduct goal, once calibrated the LPC can calculate upon request for each LGS, its return flux, its fwhm and the uplink beam scattering levels.

  8. Engineering Study on the CCD-based Measurement of Pulse Laser far-field Divergence Angle%基于CCD的脉冲激光器远场发散角工程化研究

    Institute of Scientific and Technical Information of China (English)

    邢勇; 邢冀川; 宋艳

    2011-01-01

    简述了激光光束的基本参数及特性,并介绍了采用CCD进行激光发散角测量的基本原理和装置.用CCD测量光斑可以及时获得光斑的二维扫描结果.实际工程应用时常采用CCD来测量激光远场发散角.进一步介绍了使用CCD摄像法进行发散角测量所采用的系统软件设计,首次提出了采用图像处理的方法来捕捉脉冲激光光斑.%This paper demonstrated the basic parameters and characteristics of laser beam, and introduced the basic principles and the devices used in the CCD laser divergence angle measurement method. Using CCD to measure the beam spot can gain the two-dimensional scanned result in a real-time manager. As a result, CCD was always used to measure Far-field divergence angle of the laser beam in the real engineering applications. The paper also made a further introduction of software design in the measuring system using CCD camera method. Finally, it is the first time that by the image-processing method to acquire pulse laser spot is introduced.

  9. Study of Distortions in Statistics of Counts in CCD Observations using the Fano Factor

    CERN Document Server

    Afanasieva, I V

    2016-01-01

    Factors distorting the statistics of photocounts when acquiring objects with low fluxes were considered here. Measurements of the Fano factor for existing CCD systems were conducted. The study allows one to conclude on the quality of the CCD video signal processing channel. The optimal strategy for faint object observations was suggested.

  10. Study of distortions in statistics of counts in CCD observations using the fano factor

    Science.gov (United States)

    Afanasieva, I. V.

    2016-07-01

    Factors distorting the statistics of photocounts when acquiring objects with low fluxes were considered here. Measurements of the Fano factor for existing CCD systems were conducted. The study allows one to conclude on the quality of the CCD video signal processing channel. The optimal strategy for faint object observations was suggested.

  11. VizieR Online Data Catalog: CCD photometry of CY Aqr 2012-2015 (Wiedemair+, 2016)

    Science.gov (United States)

    Wiedemair, C.; Sterken, C.; Eenmae, T.; Tuvikene, T.; Niederkofler, D.; Franzinelli, P.; Durnwalder, J.; Nardi, R.; Franzinelli, T.; Morawetz, I.; Nugroho, S. K.; Damini Hofer, J.; Seeber, J.

    2016-10-01

    All photometric data reported in this paper were obtained through CCD imaging obtained over more than 50 partial nights comprising a total of more than 20000 useful CCD frames. Table 1 gives the journal of observations. Heliocentric Julian Date, differential magnitudes ys,bs,vs,us in the standard system, and instrumental differential magnitudes yi,bi,vi,ui. (4 data files).

  12. Dark Energy Camera for Blanco

    Energy Technology Data Exchange (ETDEWEB)

    Binder, Gary A.; /Caltech /SLAC

    2010-08-25

    In order to make accurate measurements of dark energy, a system is needed to monitor the focus and alignment of the Dark Energy Camera (DECam) to be located on the Blanco 4m Telescope for the upcoming Dark Energy Survey. One new approach under development is to fit out-of-focus star images to a point spread function from which information about the focus and tilt of the camera can be obtained. As a first test of a new algorithm using this idea, simulated star images produced from a model of DECam in the optics software Zemax were fitted. Then, real images from the Mosaic II imager currently installed on the Blanco telescope were used to investigate the algorithm's capabilities. A number of problems with the algorithm were found, and more work is needed to understand its limitations and improve its capabilities so it can reliably predict camera alignment and focus.

  13. The GISMO-2 Bolometer Camera

    Science.gov (United States)

    Staguhn, Johannes G.; Benford, Dominic J.; Fixsen, Dale J.; Hilton, Gene; Irwin, Kent D.; Jhabvala, Christine A.; Kovacs, Attila; Leclercq, Samuel; Maher, Stephen F.; Miller, Timothy M.; Moseley, Samuel H.; Sharp, Elemer H.; Wollack, Edward J.

    2012-01-01

    We present the concept for the GISMO-2 bolometer camera) which we build for background-limited operation at the IRAM 30 m telescope on Pico Veleta, Spain. GISM0-2 will operate Simultaneously in the 1 mm and 2 mm atmospherical windows. The 1 mm channel uses a 32 x 40 TES-based Backshort Under Grid (BUG) bolometer array, the 2 mm channel operates with a 16 x 16 BUG array. The camera utilizes almost the entire full field of view provided by the telescope. The optical design of GISM0-2 was strongly influenced by our experience with the GISMO 2 mm bolometer camera which is successfully operating at the 30m telescope. GISMO is accessible to the astronomical community through the regular IRAM call for proposals.

  14. EDICAM (Event Detection Intelligent Camera)

    International Nuclear Information System (INIS)

    Highlights: ► We present EDICAM's hardware modules. ► We present EDICAM's main design concepts. ► This paper will describe EDICAM firmware architecture. ► Operation principles description. ► Further developments. -- Abstract: A new type of fast framing camera has been developed for fusion applications by the Wigner Research Centre for Physics during the last few years. A new concept was designed for intelligent event driven imaging which is capable of focusing image readout to Regions of Interests (ROIs) where and when predefined events occur. At present these events mean intensity changes and external triggers but in the future more sophisticated methods might also be defined. The camera provides 444 Hz frame rate at full resolution of 1280 × 1024 pixels, but monitoring of smaller ROIs can be done in the 1–116 kHz range even during exposure of the full image. Keeping space limitations and the harsh environment in mind the camera is divided into a small Sensor Module and a processing card interconnected by a fast 10 Gbit optical link. This camera hardware has been used for passive monitoring of the plasma in different devices for example at ASDEX Upgrade and COMPASS with the first version of its firmware. The new firmware and software package is now available and ready for testing the new event processing features. This paper will present the operation principle and features of the Event Detection Intelligent Camera (EDICAM). The device is intended to be the central element in the 10-camera monitoring system of the Wendelstein 7-X stellarator

  15. Camera sensor arrangement for crop/weed detection accuracy in agronomic images.

    Science.gov (United States)

    Romeo, Juan; Guerrero, José Miguel; Montalvo, Martín; Emmi, Luis; Guijarro, María; Gonzalez-de-Santos, Pablo; Pajares, Gonzalo

    2013-01-01

    In Precision Agriculture, images coming from camera-based sensors are commonly used for weed identification and crop line detection, either to apply specific treatments or for vehicle guidance purposes. Accuracy of identification and detection is an important issue to be addressed in image processing. There are two main types of parameters affecting the accuracy of the images, namely: (a) extrinsic, related to the sensor's positioning in the tractor; (b) intrinsic, related to the sensor specifications, such as CCD resolution, focal length or iris aperture, among others. Moreover, in agricultural applications, the uncontrolled illumination, existing in outdoor environments, is also an important factor affecting the image accuracy. This paper is exclusively focused on two main issues, always with the goal to achieve the highest image accuracy in Precision Agriculture applications, making the following two main contributions: (a) camera sensor arrangement, to adjust extrinsic parameters and (b) design of strategies for controlling the adverse illumination effects. PMID:23549361

  16. Camera Sensor Arrangement for Crop/Weed Detection Accuracy in Agronomic Images

    Directory of Open Access Journals (Sweden)

    Juan Romeo

    2013-04-01

    Full Text Available In Precision Agriculture, images coming from camera-based sensors are commonly used for weed identification and crop line detection, either to apply specific treatments or for vehicle guidance purposes. Accuracy of identification and detection is an important issue to be addressed in image processing. There are two main types of parameters affecting the accuracy of the images, namely: (a extrinsic, related to the sensor’s positioning in the tractor; (b intrinsic, related to the sensor specifications, such as CCD resolution, focal length or iris aperture, among others. Moreover, in agricultural applications, the uncontrolled illumination, existing in outdoor environments, is also an important factor affecting the image accuracy. This paper is exclusively focused on two main issues, always with the goal to achieve the highest image accuracy in Precision Agriculture applications, making the following two main contributions: (a camera sensor arrangement, to adjust extrinsic parameters and (b design of strategies for controlling the adverse illumination effects.

  17. Fast auto-acquisition tomography tilt series by using HD video camera in ultra-high voltage electron microscope.

    Science.gov (United States)

    Nishi, Ryuji; Cao, Meng; Kanaji, Atsuko; Nishida, Tomoki; Yoshida, Kiyokazu; Isakozawa, Shigeto

    2014-11-01

    The ultra-high voltage electron microscope (UHVEM) H-3000 with the world highest acceleration voltage of 3 MV can observe remarkable three dimensional microstructures of microns-thick samples[1]. Acquiring a tilt series of electron tomography is laborious work and thus an automatic technique is highly desired. We proposed the Auto-Focus system using image Sharpness (AFS)[2,3] for UHVEM tomography tilt series acquisition. In the method, five images with different defocus values are firstly acquired and the image sharpness are calculated. The sharpness are then fitted to a quasi-Gaussian function to decide the best focus value[3]. Defocused images acquired by the slow scan CCD (SS-CCD) camera (Hitachi F486BK) are of high quality but one minute is taken for acquisition of five defocused images.In this study, we introduce a high-definition video camera (HD video camera; Hamamatsu Photonics K. K. C9721S) for fast acquisition of images[4]. It is an analog camera but the camera image is captured by a PC and the effective image resolution is 1280×1023 pixels. This resolution is lower than that of the SS-CCD camera of 4096×4096 pixels. However, the HD video camera captures one image for only 1/30 second. In exchange for the faster acquisition the S/N of images are low. To improve the S/N, 22 captured frames are integrated so that each image sharpness is enough to become lower fitting error. As countermeasure against low resolution, we selected a large defocus step, which is typically five times of the manual defocus step, to discriminate different defocused images.By using HD video camera for autofocus process, the time consumption for each autofocus procedure was reduced to about six seconds. It took one second for correction of an image position and the total correction time was seven seconds, which was shorter by one order than that using SS-CCD camera. When we used SS-CCD camera for final image capture, it took 30 seconds to record one tilt image. We can obtain a tilt

  18. The iQID camera: An ionizing-radiation quantum imaging detector

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Brian W., E-mail: brian.miller@pnnl.gov [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); College of Optical Sciences, The University of Arizona, Tucson, AZ 85719 (United States); Gregory, Stephanie J.; Fuller, Erin S. [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Barrett, Harrison H.; Bradford Barber, H.; Furenlid, Lars R. [Center for Gamma-Ray Imaging, The University of Arizona, Tucson, AZ 85719 (United States); College of Optical Sciences, The University of Arizona, Tucson, AZ 85719 (United States)

    2014-12-11

    We have developed and tested a novel, ionizing-radiation Quantum Imaging Detector (iQID). This scintillation-based detector was originally developed as a high-resolution gamma-ray imager, called BazookaSPECT, for use in single-photon emission computed tomography (SPECT). Recently, we have investigated the detector's response and imaging potential with other forms of ionizing radiation including alpha, neutron, beta, and fission fragment particles. The confirmed response to this broad range of ionizing radiation has prompted its new title. The principle operation of the iQID camera involves coupling a scintillator to an image intensifier. The scintillation light generated by particle interactions is optically amplified by the intensifier and then re-imaged onto a CCD/CMOS camera sensor. The intensifier provides sufficient optical gain that practically any CCD/CMOS camera can be used to image ionizing radiation. The spatial location and energy of individual particles are estimated on an event-by-event basis in real time using image analysis algorithms on high-performance graphics processing hardware. Distinguishing features of the iQID camera include portability, large active areas, excellent detection efficiency for charged particles, and high spatial resolution (tens of microns). Although modest, iQID has energy resolution that is sufficient to discriminate between particles. Additionally, spatial features of individual events can be used for particle discrimination. An important iQID imaging application that has recently been developed is real-time, single-particle digital autoradiography. We present the latest results and discuss potential applications.

  19. Camera assisted multimodal user interaction

    Science.gov (United States)

    Hannuksela, Jari; Silvén, Olli; Ronkainen, Sami; Alenius, Sakari; Vehviläinen, Markku

    2010-01-01

    Since more processing power, new sensing and display technologies are already available in mobile devices, there has been increased interest in building systems to communicate via different modalities such as speech, gesture, expression, and touch. In context identification based user interfaces, these independent modalities are combined to create new ways how the users interact with hand-helds. While these are unlikely to completely replace traditional interfaces, they will considerably enrich and improve the user experience and task performance. We demonstrate a set of novel user interface concepts that rely on built-in multiple sensors of modern mobile devices for recognizing the context and sequences of actions. In particular, we use the camera to detect whether the user is watching the device, for instance, to make the decision to turn on the display backlight. In our approach the motion sensors are first employed for detecting the handling of the device. Then, based on ambient illumination information provided by a light sensor, the cameras are turned on. The frontal camera is used for face detection, while the back camera provides for supplemental contextual information. The subsequent applications triggered by the context can be, for example, image capturing, or bar code reading.

  20. Wide Field CCD photometry around nine open clusters

    CERN Document Server

    Sharma, S; Ogura, K; Mito, H; Tarusawa, K; Sagar, R

    2006-01-01

    In this paper we study the evolution of core and corona of nine open clusters using the projected radial density profiles derived from homogeneous CCD photometric data obtained through the 105-cm Kiso Schmidt telescope. The age and galactocentric distance of the target clusters varies from 16 Myr to 2000 Myr and 9 kpcto 10.8 kpc respectively. Barring Be 62, which is young open cluster, other clusters show a uniform reddening across the cluster region. The reddening in Be 62varies from $E(B-V)_{min}$= 0.70 mag to $E(B-V)_{max}$= 1.00 mag. The corona of six of the clusters in the present sample is found to be elongated, however on the basis of the present sample it is not possible to establish any correlation between the age and shape of the core. The elongated core in the case of young cluster Be 62 may reflect the initial conditions in the parental molecular cloud. The other results of the present study are (i) Core radius `$r_c$' and corona size $`r_{cn}$'/cluster radius $`r_{cl}$' are linearly correlated. (...

  1. CCD photometry of distant open clusters; 2, NGC 6791

    CERN Document Server

    Kaluzny, J; Kaluzny, Janusz; Rucinski, Slavek

    1995-01-01

    Three new photometric CCD-based datasets are presented for NGC~6791. They consist of deep UBV photometry (to V_{lim} =24, B_{lim}=24, U_{lim} = 23) of the central parts of the cluster and of selected fields around it, and of relatively shallower UBVI photometry for the whole cluster (23' \\times 23'). The data have been used to discuss the reddening, metallicity and age ofNGC~6791, a cluster which is particularly important because of (1)~its most-advanced age among open clusters, (2)~metallicity higher than solar and (3)~particularly large number of member stars. We discovered two new very blue stars increasing the total of sdB objects in the cluster to ten. They are located in a very narrow range magnitudes V=17.7 \\pm 0.5; their blue colors strongly constrain our determination of the reddening of the cluster to E(B-V)=0.17 \\pm 0.01. We detected no other blue stars except a population of faint objects with V \\approx 22 in the center of the cluster. We have used the new theoretical isochrones in a differential ...

  2. 32-megapixel dual-color CCD imaging system

    Science.gov (United States)

    Stubbs, Christopher W.; Marshall, Stuart; Cook, Kenneth H.; Hills, Robert F.; Noonan, Joseph; Akerlof, Carl W.; Alcock, Charles R.; Axelrod, Timothy S.; Bennett, D.; Dagley, K.; Freeman, K. C.; Griest, Kim; Park, Hye-Sook; Perlmutter, Saul; Peterson, Bruce A.; Quinn, Peter J.; Rodgers, A. W.; Sosin, C.; Sutherland, W. J.

    1993-07-01

    We have developed an astronomical imaging system that incorporates a total of eight 2048 X 2048 pixel CCDs into two focal planes, to allow simultaneous imaging in two colors. Each focal plane comprises four 'edge-buttable' detector arrays, on custom Kovar mounts. The clocking and bias voltage levels for each CCD are independently adjustable, but all the CCDs are operated synchronously. The sixteen analog outputs (two per chip) are measured at 16 bits with commercially available correlated double sampling A/D converters. The resulting 74 MBytes of data per frame are transferred over fiber optic links into dual-ported VME memory. The total readout time is just over one minute. We obtain read noise ranging from 6.5 e- to 10 e- for the various channels when digitizing at 34 Kpixels/sec, with full well depths (MPP mode) of approximately 100,000 e- per 15 micrometers X 15 micrometers pixel. This instrument is currently being used in a search of gravitational microlensing from compact objects in our Galactic halo, using the newly refurbished 1.3 m telescope at the Mt. Stromlo Observatory, Australia.

  3. The Spectrum of Quantum Dots Film for UV CCD

    Directory of Open Access Journals (Sweden)

    Lin Jiang

    2013-01-01

    Full Text Available A new kind of UV-responsive film with quantum dots (QDs fabricated by a spin-coating method is proposed in this paper. In a previous study, the monolayer QDs film is deposited onto fused silica slides by the spin-coating way, which has some luminous problem. The introduction of composite QDs coating which adds PEDOT:PSS and poly-TPD films to the monolayer QDs film is found to have excellent performance. The reason can be that PEDOT:PSS and poly-TPD weaken the scattering and enhance the emitting of quantum dot fluorescence. The intensity of photoluminescence (PL for composite QDs coating is dozens of times stronger than that for monolayer QDs film. Experiment results show that this composite coating has excellent fluorescent properties and emits a blue purple glow together a wide excitation spectrum field from 190 nm to 300 nm. The spectrum of the composite coating matches accurately with the detected zone of CCD, which achieves an outstanding UV-responsive coating for conventional silicon-based image sensors.

  4. When is pile-up important in the XMM-Newton EPIC cameras?

    Science.gov (United States)

    Jethwa, P.; Saxton, R.; Guainazzi, M.; Rodriguez-Pascual, P.; Stuhlinger, M.

    2015-09-01

    Context. Pile-up in X-ray charged couple device (CCD) detectors is defined as the reconstruction of independent events in the same detection cell as a single event during a read-out cycle. Pile-up can seriously compromise the spectral performance, modifying both the flux and the spectral shape of celestial sources. Aims: In this paper we define rigorous metrics to characterise the effect of pile-up in terms of flux loss and spectral distortion. Methods: We extend analytical formulae derived for pile-up on CCD detectors with the inclusion of the calibrated energy-dependence of the point spread function. We validated our analytical results through both Monte-Carlo simulations of the EPIC cameras on-board XMM-Newton and comparison with pile-up diagnostics in observed data. Results: We estimate new count rate levels corresponding to a given degree of flux loss and spectral distortion for each EPIC imaging acquisition mode and provide guidance to observers wishing to estimate these values in their own observations. Conclusions: We strongly recommend using these thresholds in planning future observations with the EPIC cameras.

  5. The carotenoid cleavage dioxygenase CCD2 catalysing the synthesis of crocetin in spring crocuses and saffron is a plastidial enzyme.

    Science.gov (United States)

    Ahrazem, Oussama; Rubio-Moraga, Angela; Berman, Judit; Capell, Teresa; Christou, Paul; Zhu, Changfu; Gómez-Gómez, Lourdes

    2016-01-01

    The apocarotenoid crocetin and its glycosylated derivatives, crocins, confer the red colour to saffron. Crocetin biosynthesis in saffron is catalysed by the carotenoid cleavage dioxygenase CCD2 (AIG94929). No homologues have been identified in other plant species due to the very limited presence of crocetin and its derivatives in the plant kingdom. Spring Crocus species with yellow flowers accumulate crocins in the stigma and tepals. Four carotenoid CCDs, namely CaCCD1, CaCCD2 and CaCCD4a/b and CaCCD4c were first cloned and characterized. CaCCD2 was localized in plastids, and a longer CCD2 version, CsCCD2L, was also localized in this compartment. The activity of CaCCD2 was assessed in Escherichia coli and in a stable rice gene function characterization system, demonstrating the production of crocetin in both systems. The expression of all isolated CCDs was evaluated in stigma and tepals at three key developmental stages in relation with apocarotenoid accumulation. CaCCD2 expression parallels crocin accumulation, but C14 apocarotenoids most likely are associated to the CaCCD1 activity in Crocus ancyrensis flowers. The specific CCD2 localization and its membrane interaction will contribute to the development of a better understanding of the mechanism of crocetin biosynthesis and regulation in the chromoplast. PMID:26377696

  6. Searching for bulk motions in the ICM of massive, merging clusters with Chandra CCD data

    CERN Document Server

    Liu, Ang; Tozzi, Paolo; Zhu, Zong-Hong

    2016-01-01

    We search for bulk motions in the Intra Cluster Medium (ICM) of massive clusters showing evidence of an ongoing or a recent major merger, with spatially resolved spectroscopy in {\\sl Chandra} CCD data. We identify a sample of 6 merging clusters with >150 ks {\\sl Chandra} exposure in the redshift range 0.1 1000$ km/s in the ICM of massive merging clusters at 0.1 < z < 0.3. Despite the CCD spectral resolution is not sufficient for a detailed analysis of the ICM dynamics, {\\sl Chandra} CCD data constitute a key diagnostic tool complementary to X-ray bolometers onboard future X-ray missions.

  7. Development of single frame X-ray framing camera for pulsed plasma experiments

    Indian Academy of Sciences (India)

    J Upadhyay; J A Chakera; C P Navathe; P A Naik; A S Joshi; P D Gupta

    2006-10-01

    A single-frame X-ray framing camera has been set up for fast imaging of X-ray emissions from pulsed plasma sources. It consists of two parts, viz. an X-ray pin-hole camera using an open-ended microchannel plate (MCP) detector coupled to a CCD camera, and a high voltage short duration gate pulse for the MCP. The camera uses a 10-m pin-hole aperture for imaging on the MCP detector with a magnification of 6X. The high voltage pulser circuit generates a pulse of variable duration from 5 to 30 ns (at 70% of peak amplitude) with variable amplitude from 800 V to 1·25 kV, and is triggered through a laser pulse synchronized with the event to be recorded. The performance of the system has been checked by recording X-ray emission from a laser-produced copper plasma. A reduction factor of ∼6·5 is seen in the dark current contribution as the MCP gate pulse is decreased from 250s to 5 ns duration.

  8. Application of Correlated Double Sampling in Space TDICCD Camera

    Institute of Scientific and Technical Information of China (English)

    HUANG Mei-ling; ZHANG Bo-heng; BIAN Chuan-ping; LI Lu-yao

    2005-01-01

    As a sampling technique for CCD output video signal, the correlated double sampling(CDS)technique is described as well as the filtering effects of the CDS technique on the output noise of CCD including the reset noise of CCD, the white noise of output amplifier and 1/f noise. From real application of CDS device TH7982A, it is concluded that the output signal-to-noise ratio of 50 dB for CCD signal can be obtained.

  9. Lytro camera technology: theory, algorithms, performance analysis

    Science.gov (United States)

    Georgiev, Todor; Yu, Zhan; Lumsdaine, Andrew; Goma, Sergio

    2013-03-01

    The Lytro camera is the first implementation of a plenoptic camera for the consumer market. We consider it a successful example of the miniaturization aided by the increase in computational power characterizing mobile computational photography. The plenoptic camera approach to radiance capture uses a microlens array as an imaging system focused on the focal plane of the main camera lens. This paper analyzes the performance of Lytro camera from a system level perspective, considering the Lytro camera as a black box, and uses our interpretation of Lytro image data saved by the camera. We present our findings based on our interpretation of Lytro camera file structure, image calibration and image rendering; in this context, artifacts and final image resolution are discussed.

  10. Architectural Design Document for Camera Models

    DEFF Research Database (Denmark)

    Thuesen, Gøsta

    1998-01-01

    Architecture of camera simulator models and data interface for the Maneuvering of Inspection/Servicing Vehicle (MIV) study.......Architecture of camera simulator models and data interface for the Maneuvering of Inspection/Servicing Vehicle (MIV) study....

  11. CCD detectors for spectroscopy and imaging of x-rays with the eROSITA space telescope

    Science.gov (United States)

    Meidinger, N.; Andritschke, R.; Ebermayer, S.; Elbs, J.; Hälker, O.; Hartmann, R.; Herrmann, S.; Kimmel, N.; Predehl, P.; Schächner, G.; Soltau, H.; Strüder, L.; Tiedemann, L.

    2009-08-01

    A special type of CCD, the so-called PNCCD, was originally developed for the focal plane camera of the XMMNewton space telescope. After the satellite launch in 1999, the MPI Halbleiterlabor continued the detector development for various ground-based applications. Finally, a new X-ray PNCCD was designed again for a space telescope named eROSITA. The space telescope will be equipped with an array of seven parallel oriented X-ray mirror systems of Wolter-I type and seven cameras, placed in their foci. This instrumentation will permit the exploration of the X-ray universe in the energy band from 0.3 keV up to 10 keV with a time resolution of 50 ms for a full image comprising 384 x 384 pixels. eROSITA will be accommodated on the new Russian Spectrum-RG satellite. The mission was already approved by the responsible German and Russian space agencies. The detector development is focussed to fulfil the scientific specifications for detector performance under the constraints of all the mechanical, power, thermal and radiation hardness issues for space instrumentation. This considers also the recent change of the satellite's orbit. The Lagrange point L2 was decided as new destination of the satellite instead of a low-Earth orbit (LEO). We present a detailed description of the detector system and the current development status. The most recent test results are reported here. Essential steps for completion of the seven focal plane detectors until satellite launch in 2012 will be itemized.

  12. Discriminação de variedades de citros em imagens CCD/CBERS-2 Discrimination of citrus varieties using CCD/CBERS-2 satellite imagery

    Directory of Open Access Journals (Sweden)

    Ieda Del'Arco Sanches

    2008-02-01

    Full Text Available O presente trabalho teve o objetivo de avaliar as imagens CCD/CBERS-2 quanto à possibilidade de discriminarem variedades de citros. A área de estudo localiza-se em Itirapina (SP e, para este estudo, foram utilizadas imagens CCD de três datas (30/05/2004, 16/08/2004 e 11/09/2004. Um modelo que integra os elementos componentes da cena citrícola sensoriada é proposto com o objetivo de explicar a variabilidade das respostas das parcelas de citros em imagens orbitais do tipo CCD/CBERS-2. Foram feitas classificações pelos algoritmos Isoseg e Maxver e, de acordo com o índice kappa, concluiu-se que é possível obterem-se exatidões qualificadas como muito boas, sendo que as melhores classificações foram conseguidas com imagens da estação seca.This paper was aimed at evaluating the possibility of discriminating citrus varieties in CCD imageries from CBERS-2 satellite ("China-Brazil Earth Resouces Satellite". The study area is located in Itirapina, São Paulo State. For this study, three CCD images from 2004 were acquired (May 30, August 16, and September 11. In order to acquire a better understanding and for explaining the variability of the spectral behavior of the citrus areas in orbital images (like as the CCD/CBERS-2 images a model that integrates the elements of the citrus scene is proposed and discussed. The images were classified by Isoseg and MaxVer classifiers. According to kappa index, it was possible to obtain classifications qualified as 'very good'. The best results were obtained with the images from the dry season.

  13. Electronographic cameras for space astronomy.

    Science.gov (United States)

    Carruthers, G. R.; Opal, C. B.

    1972-01-01

    Magnetically-focused electronographic cameras have been under development at the Naval Research Laboratory for use in far-ultraviolet imagery and spectrography, primarily in astronomical and optical-geophysical observations from sounding rockets and space vehicles. Most of this work has been with cameras incorporating internal optics of the Schmidt or wide-field all-reflecting types. More recently, we have begun development of electronographic spectrographs incorporating an internal concave grating, operating at normal or grazing incidence. We also are developing electronographic image tubes of the conventional end-window-photo-cathode type, for far-ultraviolet imagery at the focus of a large space telescope, with image formats up to 120 mm in diameter.

  14. An optical metasurface planar camera

    CERN Document Server

    Arbabi, Amir; Kamali, Seyedeh Mahsa; Horie, Yu; Han, Seunghoon; Faraon, Andrei

    2016-01-01

    Optical metasurfaces are 2D arrays of nano-scatterers that modify optical wavefronts at subwavelength spatial resolution. They are poised to revolutionize optical design by enabling complex low cost systems where multiple metasurfaces are lithographically stacked on top of each other and are integrated with electronics. For imaging applications, metasurface stacks can perform sophisticated image corrections and can be directly integrated with image sensors. Here, we demonstrate this concept with a miniature flat camera integrating a monolithic metasurface lens doublet corrected for monochromatic aberrations, and an image sensor. The doublet lens, which acts as a fisheye photographic objective, has an f-number of 0.9, an angle-of-view larger than 60$^\\circ$$\\times$60$^\\circ$, and operates at 850 nm wavelength with large transmission. The camera exhibits high image quality, which indicates the potential of this technology to produce a paradigm shift in future designs of imaging systems for microscopy, photograp...

  15. Camera Movement in Narrative Cinema

    DEFF Research Database (Denmark)

    Nielsen, Jakob Isak

    2007-01-01

    Just like art historians have focused on e.g. composition or lighting, this dissertation takes a single stylistic parameter as its object of study: camera movement. Within film studies this localized avenue of middle-level research has become increasingly viable under the aegis of a perspective...... known as ‘the poetics of cinema.’ The dissertation embraces two branches of research within this perspective: stylistics and historical poetics (stylistic history). The dissertation takes on three questions in relation to camera movement and is accordingly divided into three major sections. The first...... cinematic poetics and interpretive criticism sensitive to style may gain from each other. There is no reason why stylistically informed interpretive criticism cannot be considered within a functional framework and there is no reason why one should not use a functional taxonomy as a basis on which to launch...

  16. Combustion pinhole-camera system

    Science.gov (United States)

    Witte, A.B.

    1982-05-19

    A pinhole camera system is described utilizing a sealed optical-purge assembly which provides optical access into a coal combustor or other energy conversion reactors. The camera system basically consists of a focused-purge pinhole optical port assembly, a conventional TV vidicon receiver, an external, variable density light filter which is coupled electronically to the vidicon automatic gain control (agc). The key component of this system is the focused-purge pinhole optical port assembly which utilizes a purging inert gas to keep debris from entering the port and a lens arrangement which transfers the pinhole to the outside of the port assembly. One additional feature of the port assembly is that it is not flush with the interior of the combustor.

  17. Side 2: MSM positioning of STIS CCD Modes

    Science.gov (United States)

    Sahu, Kailash

    2000-07-01

    The MSM positions for different STIS modes are slightly different when the STIS is run through side 2 than when it is run from side 1. These MSM positions for various STIS prime CCD modes shall be confirmed by taking images with the IM Pt/Cr/Ne calibration lamp. For first order long-slit modes, the exposures shall be made through 52x0.1arcsec slit. For the echelle modes, the exposures shall be made through echelle slits of the nominal height, to avoid order confusion. One exposure shall be taken for each prime mode except for the medium dispersion{M}, long slit modes. For the medium dispersion, long-slit modes, additional exposures shall be taken at the long and short wavelength settings of the nominal scan range. Exposures shall be sufficiently long to bring out enough line features to confirm wavelength identifications, with sufficient signal to noise to reveal the shadows of the fiducials in the long slit images to confirm spatial pointing. This activity will test all primary modes and test the extremes of the MSM scanning cylinders by observing the extreme settings of the modes. RESULTS: All images will be downlinked and analyzed. The results are confirmation of the standard MSM encoder values for each mode. If the wavelength shifts are less than the budgeted value, the changes will be handled through updating the siaf files. If excess shifts are seen, new MSM positions will be derived and uplinked to the onboard MSM pointing table. Any modes for which revised MSM positions are uplinked will have to be re-observed for confirmation that the correct offsets were applied.

  18. ISO camera array development status

    Science.gov (United States)

    Sibille, F.; Cesarsky, C.; Agnese, P.; Rouan, D.

    1989-01-01

    A short outline is given of the Infrared Space Observatory Camera (ISOCAM), one of the 4 instruments onboard the Infrared Space Observatory (ISO), with the current status of its two 32x32 arrays, an InSb charge injection device (CID) and a Si:Ga direct read-out (DRO), and the results of the in orbit radiation simulation with gamma ray sources. A tentative technique for the evaluation of the flat fielding accuracy is also proposed.

  19. Graphic design of pinhole cameras

    Science.gov (United States)

    Edwards, H. B.; Chu, W. P.

    1979-01-01

    The paper describes a graphic technique for the analysis and optimization of pinhole size and focal length. The technique is based on the use of the transfer function of optical elements described by Scott (1959) to construct the transfer function of a circular pinhole camera. This transfer function is the response of a component or system to a pattern of lines having a sinusoidally varying radiance at varying spatial frequencies. Some specific examples of graphic design are presented.

  20. On the absolute calibration of SO2 cameras

    Directory of Open Access Journals (Sweden)

    J. Zielcke

    2012-09-01

    Full Text Available Sulphur dioxide emission flux measurements are an important tool for volcanic monitoring and eruption risk assessment. The SO2 camera technique remotely measures volcanic emissions by analysing the ultraviolet absorption of SO2 in a narrow spectral window between 305 nm and 320 nm using solar radiation scattered in the atmosphere. The SO2 absorption is selectively detected by mounting band-pass interference filters in front of a two-dimensional, UV-sensitive CCD detector. While this approach is simple and delivers valuable insights into the two-dimensional SO2 distribution, absolute calibration has proven to be difficult. An accurate calibration of the SO2 camera (i.e., conversion from optical density to SO2 column density, CD is crucial to obtain correct SO2 CDs and flux measurements that are comparable to other measurement techniques and can be used for volcanological applications. The most common approach for calibrating SO2 camera measurements is based on inserting quartz cells (cuvettes containing known amounts of SO2 into the light path. It has been found, however, that reflections from the windows of the calibration cell can considerably affect the signal measured by the camera. Another possibility for calibration relies on performing simultaneous measurements in a small area of the camera's field-of-view (FOV by a narrow-field-of-view Differential Optical Absorption Spectroscopy (NFOV-DOAS system. This procedure combines the very good spatial and temporal resolution of the SO2 camera technique with the more accurate column densities obtainable from DOAS measurements. This work investigates the uncertainty of results gained through the two commonly used, but quite different calibration methods (DOAS and calibration cells. Measurements with three different instruments, an SO2 camera, a NFOV-DOAS system and an Imaging DOAS (IDOAS, are presented. We compare the calibration-cell approach with the calibration from the NFOV-DOAS system. The

  1. 21 CFR 886.1120 - Opthalmic camera.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Opthalmic camera. 886.1120 Section 886.1120 Food... DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1120 Opthalmic camera. (a) Identification. An ophthalmic camera is an AC-powered device intended to take photographs of the eye and the surrounding...

  2. 21 CFR 892.1110 - Positron camera.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Positron camera. 892.1110 Section 892.1110 Food... DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1110 Positron camera. (a) Identification. A positron camera is a device intended to image the distribution of positron-emitting radionuclides in the...

  3. 16 CFR 501.1 - Camera film.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Camera film. 501.1 Section 501.1 Commercial Practices FEDERAL TRADE COMMISSION RULES, REGULATIONS, STATEMENT OF GENERAL POLICY OR INTERPRETATION AND... 500 § 501.1 Camera film. Camera film packaged and labeled for retail sale is exempt from the...

  4. Solid-state array cameras.

    Science.gov (United States)

    Strull, G; List, W F; Irwin, E L; Farnsworth, D L

    1972-05-01

    Over the past few years there has been growing interest shown in the rapidly maturing technology of totally solid-state imaging. This paper presents a synopsis of developments made in this field at the Westinghouse ATL facilities with emphasis on row-column organized monolithic arrays of diffused junction phototransistors. The complete processing sequence applicable to the fabrication of modern highdensity arrays is described from wafer ingot preparation to final sensor testing. Special steps found necessary for high yield processing, such as surface etching prior to both sawing and lapping, are discussed along with the rationale behind their adoption. Camera systems built around matrix array photosensors are presented in a historical time-wise progression beginning with the first 50 x 50 element converter developed in 1965 and running through the most recent 400 x 500 element system delivered in 1972. The freedom of mechanical architecture made available to system designers by solid-state array cameras is noted from the description of a bare-chip packaged cubic inch camera. Hybrid scan systems employing one-dimensional line arrays are cited, and the basic tradeoffs to their use are listed. PMID:20119094

  5. Unassisted 3D camera calibration

    Science.gov (United States)

    Atanassov, Kalin; Ramachandra, Vikas; Nash, James; Goma, Sergio R.

    2012-03-01

    With the rapid growth of 3D technology, 3D image capture has become a critical part of the 3D feature set on mobile phones. 3D image quality is affected by the scene geometry as well as on-the-device processing. An automatic 3D system usually assumes known camera poses accomplished by factory calibration using a special chart. In real life settings, pose parameters estimated by factory calibration can be negatively impacted by movements of the lens barrel due to shaking, focusing, or camera drop. If any of these factors displaces the optical axes of either or both cameras, vertical disparity might exceed the maximum tolerable margin and the 3D user may experience eye strain or headaches. To make 3D capture more practical, one needs to consider unassisted (on arbitrary scenes) calibration. In this paper, we propose an algorithm that relies on detection and matching of keypoints between left and right images. Frames containing erroneous matches, along with frames with insufficiently rich keypoint constellations, are detected and discarded. Roll, pitch yaw , and scale differences between left and right frames are then estimated. The algorithm performance is evaluated in terms of the remaining vertical disparity as compared to the maximum tolerable vertical disparity.

  6. PERFORMANCE EVALUATION OF SEVERAL FUSION APPROACHES FOR CCD/SAR IMAGES

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Several image fusion approaches for CCD/SAR images are studied and the performance evaluation of these fusion approaches is completed in this paper. Firstly, the preprocessing of CCD/SAR images before fusion is fulfilled. Then, the image fusion methods including linear superposition, nonlinear operator method and multiresolution methods, of which the multiresolution methods include Laplacian pyramid, ratio pyramid, contrast pyramid, gradient pyramid, morphological pyramid and discrete wavelet transform, are adopted to fuse two types of images. Lastly, the four performance measures, standard deviation, entropy, cross entropy and spatial frequency, are calculated to compare the fusion results by different fusion approaches in this paper. Experimental results show that contrast pyramid, morphology pyramid and discrete wavelet transformation in multiresolution approaches are more suitable for CCD/SAR image fusion than other ones proposed in this paper and the objective performance evaluation of CCD/SAR image fusion approaches are effective.

  7. A tilted fiber-optic plate coupled CCD detector for high resolution neutron imaging

    International Nuclear Information System (INIS)

    One of these efforts is that a tilted scintillator geometry and lens coupled CCD detector for neutron imaging system were used to improve spatial resolution in one dimension. The increased spatial resolution in one dimension was applied to fuel cell study. However, a lens coupled CCD detector has lower sensitivity than a fiber-optic plate coupled CCD detector due to light loss. In this research, a tilted detector using fiber-optic plate coupled CCD detector was developed to improve resolution and sensitivity. In addition, a tilted detector can prevent an image sensor from direct radiation damage. Neutron imaging has been used for fuel cell study, lithium ion battery study, and many scientific applications. High quality neutron imaging is demanded for more detailed studies of applications, and spatial resolution should be considered to get high quality neutron imaging. Therefore, there were many efforts to improve spatial resolution

  8. Researchers develop CCD image sensor with 20ns per row parallel readout time

    CERN Multimedia

    Bush, S

    2004-01-01

    "Scientists at the Rutherford Appleton Laboratory (RAL) in Oxfordshire have developed what they claim is the fastest CCD (charge-coupled device) image sensor, with a readout time which is 20ns per row" (1/2 page)

  9. Compact and fully automated system for monitoring photodynamic therapy, based on two LEDs and a single CCD

    Science.gov (United States)

    Kleshnin, M. S.; Fiks, I. I.; Plekhanov, V. I.; Gamayunov, S. V.; Turchin, I. V.

    2015-11-01

    Photodynamic therapy is one of the most promising methods for the treatment of oncological, inflammatory and degenerative diseases of the skin. This technique is based on light irradiation of a photosensitizer that has been injected into the patient’s body prior to the procedure, with determination of the efficacy of treatment requiring proper assessment of the drug concentration in the tissue lesion and the extent of sensitizer photobleaching during irradiation. We have developed a compact and low cost device based on a fluorescence imaging for localizing the tumor in the patient’s body, tracking the position of the tissue lesion during involuntary movements of the patient, estimating accumulation of the sensitizer in the tumor relative to the surrounding tissues and monitoring photobleaching of the sensitizer during laser irradiation. The system that has been created is compatible with any therapeutic laser and includes a single CCD camera and two LEDs, one in the excitation band and the other in the emission band of the ‘Photoditazin’ sensitizer. In this letter we also present the test results of the device in model experiments and in preliminary clinical trials. The results obtained clearly show the efficacy of the system for monitoring sensitizer photobleaching during photodynamic therapy.

  10. A concept for the readout of multichannel detectors by using analog signal transmission via optical fibres coupled to a fast CCD

    International Nuclear Information System (INIS)

    Recent developments in the field of electro-optical components allowed one to transform fast analog electrical signals into fast light pulses in a wide dynamic range and to send them via optical fibres over relatively long distances with very low time dispersion and amplitude losses. Here we propose to use the analog signal fibre transmission technique in combination with fast CCDs for the data acquisition of multichannel detectors as, for example, for the read out of imaging cameras of atmospheric Cherenkov telescopes. Hundreds of signal channels can be read out by using commercially available single CCD module in fast gated mode. The latter can provide high amplitude resolution and an acquisition rate of up to a few hundred Hz. Such a system can provide significantly lower costs compared to traditionally used amplitude digitizing systems

  11. Performance evaluation of CCD- and mobile-phone-based near-infrared fluorescence imaging systems with molded and 3D-printed phantoms

    Science.gov (United States)

    Wang, Bohan; Ghassemi, Pejhman; Wang, Jianting; Wang, Quanzeng; Chen, Yu; Pfefer, Joshua

    2016-03-01

    Increasing numbers of devices are emerging which involve biophotonic imaging on a mobile platform. Therefore, effective test methods are needed to ensure that these devices provide a high level of image quality. We have developed novel phantoms for performance assessment of near infrared fluorescence (NIRF) imaging devices. Resin molding and 3D printing techniques were applied for phantom fabrication. Comparisons between two imaging approaches - a CCD-based scientific camera and an NIR-enabled mobile phone - were made based on evaluation of the contrast transfer function and penetration depth. Optical properties of the phantoms were evaluated, including absorption and scattering spectra and fluorescence excitation-emission matrices. The potential viability of contrastenhanced biological NIRF imaging with a mobile phone is demonstrated, and color-channel-specific variations in image quality are documented. Our results provide evidence of the utility of novel phantom-based test methods for quantifying image quality in emerging NIRF devices.

  12. JAstroCam - A New Tool for Data Gathering with CCD

    Science.gov (United States)

    Budyn, M.; Zola, S.; Wojcik, K.

    2010-12-01

    We present a new acquisition program for observations with CCD. The code is written in the JAVA language, currently supports Photometrics S300, SBIG, APOGEE and Andor CCDs. New hardware support can be extended by adding plugins for either a new type of CCD or a filter wheel. The software is capable of performing an on-line reduction of frames coming in real time either on non-processed or reduced for bias/dark/flat frames.

  13. Re-analysis of the Giotto mission data obtained by the Halley Multicolour Camera (HMC) with aim of large particles detection in the inner coma of comet 1P/Halley

    Science.gov (United States)

    Shalygina, O. S.; Keller, H. U.; Blum, J.

    2015-10-01

    The Giotto spacecraft (SC) mission was the ESA's first interplanetary mission, that made close-up observations of a comet. The Giotto spaceprobe passed the nucleus of comet Halley at a fly-by distance of only 596 km early on 14 March 1986. During the approach, 2304 images of the comet were taken by the Halley Multicolour Camera (HMC) through different filters. The HMC experiment was a high-resolution imaging system onboard the spin-stabilized SC. Its spin axis was closely aligned with the SC-comet relative-velocity vector. Pointing of the camera was achieved by the spinning motion of the SC for one dimension and by rotation about an axis perpendicular to the spin of the SC for the other dimension. The spin period was about 4 seconds and the nominal imaging resolution was 22 m at 1000 km distance [1, 2]. HMC was taking images in the so-called Time Delay and Integration mode [2]. In this mode, only a narrow part of the CCD detector was uncovered, and vertical scan-out was provided by the spacecraft (and therefore the camera) spinning. During this spinning charges were transferred line-by-line in the same direction. The slit was made wider than 1 pixel, which increased exposure time but degraded the sharpness to some extent. The portion of the sky swept by the exposed lines during image acquisition was a section of an annulus resulting in over-sampling at the end of the exposed lines nearest the SC spin axis and under-sampling at the other end [2]. Several impacts of dust particles on the spacecraft were detected during the fly-by by the analysis of the changes in the SC attitude and spin period [1]. The changes occurred in large steps, requiring many impacts of massive dust particles well above an effective mass of 10 mg, which implies that a significant part of the cometary dust mass is contained in rather large particles. Moreover, since the time of the Giotto mission, large dust particles have been detected in the inner coma of other comets. The coma of comet 103P

  14. Design of dual Beam multi-wavelength UV-visible absorbance detectors based on CCD

    Institute of Scientific and Technical Information of China (English)

    SHEN Shuang; TANG Zhen-an; LI Tong

    2006-01-01

    @@ Because the general multi-wavelength UV-Visible absorbance detector cannot avoid the noise and drift resulting from the intensity fluctuation of the light source,a dual beam multi-wavelength UV-Visible detector based on CCD was designed.The ray of light source is divided into a signal ray and a reference ray by the beam splitter after it passes through the chopper.The signal ray shines into the sample cell.The signal ray passing through the sample cell falls onto a concave mirror which focuses it onto a slot that is imaged on one portion of CCD by a concave grating.The reference ray is imaged on the other portion of CCD by the concave grating after the slot.The signal spectrum,the reference spectrum and the dark current of CCD can be measured on the same CCD under the cooperation of the optical system and accessorial circuits.The real-time compensation for the signal spectrum by using the reference spectrum and the dark current of CCD can effectively depress the noise and drift of the detector.The short-term noise is 10-5AU and the drift is 10-4AU/h.

  15. First results with he pn-CCD detector system for the XMM satellite mission

    International Nuclear Information System (INIS)

    The pn-CCD is a novel CCD type which is developed for fast X-ray imaging and spectroscopy for the X-ray Multi Mirror (XMM) satellite emission. Each 200x64 pixel large pn-CCD unit with a sensitive area of 3x1 cm2 is a fully depleted detector. Full depletion allows for high photon detection efficiency (>90% in the energy range of 500 eV-10 keV), for a small input capacitance necessary for low noise signal measurements and for backward illumination. For good time resolution and low noise performance each of the 64 CCD channels is terminated with an integrated input-JFET for signal amplification. With the use of the CMOS Amplifier and Multiplexing Chip (CAMEX64B) it is possible to read out the 64 CCD channels in parallel before they are multiplexed and sent to an ADC. For the first time the system of a 64 channel pn-CCD together with CAMEX64B readout, ADC conversion and data acquisition and storage has been brought into operation. First images of an 55Fe X-ray source are presented and discussed. (orig.)

  16. Using a CCD for the direct detection of electrons in a low energy space plasma spectrometer

    Science.gov (United States)

    Bedington, R.; Kataria, D.; Walton, D.

    2012-01-01

    An E2V CCD64 back-illuminated, ion-implanted CCD (charge-coupled device) has been used as a direct electron imaging detector with CATS (Conceptual And Tiny Spectrometer), a highly miniaturised prototype plasma analyser head. This is in place of an MCP (microchannel plate) with a position sensing anode which would more conventionally be used as a detector in traditional low energy space plasma analyser instruments. The small size of CATS however makes it well matched to the size of the CCD, and the ion implants reduce the depth of the CCD backside electron potential well making it more sensitive to lower energy electrons than standard untreated silicon. Despite ionisation damage from prolonged exposure to excessively energetic electrons, the CCD has been able to detect electrons with energies above 500eV, at temperatures around room temperature. Using both a long integration 'current measuring' mode and a short integration `electron counting' mode it has been used to image the low energy electrons exiting the analyser, enhancing our understanding of the CATS electrostatic optics. The CCD has been selected as the detector for use with CATS for an instrument on a low-altitude student sounding rocket flight. Although it cannot detect the lowest energy electrons that an MCP can detect, and it is more sensitive to stray light, the low voltages required, the lack of vacuum requirements and its novelty and availability made it the most attractive candidate detector.

  17. One method for HJ-1-A HSI and CCD data fusion

    International Nuclear Information System (INIS)

    HJ-1-A satellite, developed by China independently, was equipped with two sensors of Hyper Spectral Imager (HSI) and multispectral sensor (CCD). In this paper, we examine the benefits of combining data from CCD data (high-spatial-resolution, low-spectral-resolution image) with HSI data (low -spatial-resolution, high -spectral-resolution image). Due to the same imaging time and similar spectral regime, the CCD and HSI data can be registered with each other well, and the difference between CCD and HSI data mainly is systematic bias. The approach we have been investigating compares the spectral information present in the multispectral image to the spectral content in the hyperspectral image, and derives a set of equations to approximately acquire the systematic bias between the two sensors. The systematic bias is then applied to the interpolated high-spectral CCD image to produce a fused product. This fused image has the spectral resolution of the hyperspectral image (HSI) and the spatial resolution of the multispectral image (CCD). It is capable of full exploitation as a hyperspectral image. We evaluate this technique using the data of Honghe wetland and show both good spectral and visual fidelity. An analysis of SAM classification test case shows good result when compared to original image. All in all, the approach we developed here provides a means for fusing data from HJ-1-A satellite to produce a spatial-resolution-enhanced hyperspectral data cube that can be further analyzed by spectral classification and detection algorithms

  18. HHEBBES! All sky camera system: status update

    Science.gov (United States)

    Bettonvil, F.

    2015-01-01

    A status update is given of the HHEBBES! All sky camera system. HHEBBES!, an automatic camera for capturing bright meteor trails, is based on a DSLR camera and a Liquid Crystal chopper for measuring the angular velocity. Purpose of the system is to a) recover meteorites; b) identify origin/parental bodies. In 2015, two new cameras were rolled out: BINGO! -alike HHEBBES! also in The Netherlands-, and POgLED, in Serbia. BINGO! is a first camera equipped with a longer focal length fisheye lens, to further increase the accuracy. Several minor improvements have been done and the data reduction pipeline was used for processing two prominent Dutch fireballs.

  19. Mini gamma camera, camera system and method of use

    Science.gov (United States)

    Majewski, Stanislaw; Weisenberger, Andrew G.; Wojcik, Randolph F.

    2001-01-01

    A gamma camera comprising essentially and in order from the front outer or gamma ray impinging surface: 1) a collimator, 2) a scintillator layer, 3) a light guide, 4) an array of position sensitive, high resolution photomultiplier tubes, and 5) printed circuitry for receipt of the output of the photomultipliers. There is also described, a system wherein the output supplied by the high resolution, position sensitive photomultipiler tubes is communicated to: a) a digitizer and b) a computer where it is processed using advanced image processing techniques and a specific algorithm to calculate the center of gravity of any abnormality observed during imaging, and c) optional image display and telecommunications ports.

  20. Research on the affect of differential-images technique to the resolution of infrared spatial camera

    Science.gov (United States)

    Jin, Guang; An, Yuan; Qi, Yingchun; Hu, Fusheng

    2007-12-01

    The optical system of infrared spatial camera adopts bigger relative aperture and bigger pixel size on focal plane element. These make the system have bulky volume and low resolution. The potential of the optical systems can not be exerted adequately. So, one method for improving resolution of infrared spatial camera based on multi-frame difference-images is introduced in the dissertation. The method uses more than one detectors to acquire several difference images, and then reconstructs a new high-resolution image from these images through the relationship of pixel grey value. The technique of difference-images that uses more than two detectors is researched, and it can improve the resolution 2.5 times in theory. The relationship of pixel grey value between low-resolution difference-images and high-resolution image is found by analyzing the energy of CCD sampling, a general relationship between the enhanced times of the resolution of the detected figure with differential method and the least count of CCD that will be used to detect figure is given. Based on the research of theory, the implementation process of utilizing difference-images technique to improve the resolution of the figure was simulated used Matlab software by taking a personality image as the object, and the software can output the result as an image. The result gotten from the works we have finished proves that the technique is available in high-resolution image reconstruction. The resolution of infrared spatial camera can be improved evidently when holding the size of optical structure or using big size detector by applying for difference image technique. So the technique has a high value in optical remote fields.

  1. Predicting Chandra CCD Degradation with the Chandra Radiation Model

    Science.gov (United States)

    Minow, Joseph I.; Blackwell, William C.; DePasquale, Joseph M.; Grant, Catherine E.; O'Dell, Stephen L.; Plucinsky, Paul P.; Schwartz, Daniel A.; Spitzbart, Bradley D.; Wolk, Scott J.

    2008-01-01

    Not long after launch of the Chandra X-Ray Observatory, it was discovered that the Advanced CCD Imaging Spectrometer (ACIS) detector was rapidly degrading due to radiation. Analysis by Chandra personnel showed that this degradation was due to 10w energy protons (100 - 200 keV) that scattered down the optical path onto the focal plane. In response to this unexpected problem, the Chandra Team developed a radiation-protection program that has been used to manage the radiation damage to the CCDs. This program consists of multiple approaches - scheduled sating of the ACIS detector from the radiation environment during passage through radiation belts, real-time monitoring of space weather conditions, on-board monitoring of radiation environment levels, and the creation of a radiation environment model for use in computing proton flux and fluence at energies that damage the ACIS detector. This radiation mitigation program has been very successful. The initial precipitous increase in the CCDs' charge transfer inefficiency (CTI) resulting from proton damage has been slowed dramatically, with the front-illuminated CCDS having an increase in CTI of only 2.3% per year, allowing the ASIS detector's expected lifetime to exceed requirements. This paper concentrates on one aspect of the Chandra radiation mitigation program, the creation of the Chandra Radiation Model (CRM). Because of Chandra's highly elliptical orbit, the spacecraft spends most of its time outside of the trapped radiation belts that present the severest risks to the ACIS detector. However, there is still a proton flux environment that must be accounted for in all parts of Chandra's orbit. At the time of Chandra's launch there was no engineering model of the radiation environment that could be used in the outer regions of the spacecraft's orbit, so the CRM was developed to provide the flux environment of 100 - 200 keV protons in the outer magnetosphere, magnetosheath, and solar wind regions of geospace. This

  2. Experimental research on thermoelectric cooler for imager camera thermal control

    Science.gov (United States)

    Hu, Bing-ting; Kang, Ao-feng; Fu, Xin; Jiang, Shi-chen; Dong, Yao-hai

    2013-09-01

    Conventional passive thermal design failed to satisfy CCD's temperature requirement on a geostationary earth orbit satellite Imager camera because of the high power and low working temperature, leading to utilization of thermoelectric cooler (TEC) for heat dissipation. TEC was used in conjunction with the external radiator in the CCDs' thermal design. In order to maintain the CCDs at low working temperature, experimental research on the performance of thermoelectric cooler was necessary and the results could be the guide for the application of TEC in different conditions. The experimental system to evaluate the performance of TEC was designed and built, consisting of TEC, heat pipe, TEC mounting plate, radiator and heater. A series of TEC performance tests were conducted for domestic and oversea TECs in thermal vacuum environment. The effects of TEC's mounting, input power and heat load on the temperature difference of TEC's cold and hot face were explored. Results demonstrated that the temperature difference of TEC's cold and hot face was slightly increased when TEC's operating voltage reached 80% of rating voltage, which caused the temperature rise of TEC's hot face. It recommended TEC to operate at low voltage. Based on experiment results, thermal analysis indicated that the temperature difference of TEC's cold and hot face could satisfy the temperature requirement and still had surplus.

  3. Síntese, caracterização e estudos de interação de um análogo da antitoxina CcdA empregando fluorescência no estado estacionário Synthesis, characterization and interaction studies of an analog of CcdA antitoxin by steady state fluorescence

    Directory of Open Access Journals (Sweden)

    Camila Aparecida Cotrim

    2010-01-01

    Full Text Available Toxin-antitoxin (TA systems contribute to plasmid stability by a mechanism called post-segregational killing. The ccd was the first TA system to be discovered with CcdB being the toxin and CcdA the antitoxin. CcdA, an 8.3 kDa protein, interacts with CcdB (11.7 kDa, preventing the cytotoxic activity of CcdB on the DNA gyrase. As an approach to understanding this interaction, CcdA41, a polypeptide derived from CcdA, was synthesized by solid-phase methodology and its interaction with CcdB was analyzed by steady state fluorescence. CcdA41 formed a stable complex with CcdBET2, a peptide based on CcdB, the more recently described bacterial topoisomerase inhibitor.

  4. Hidden Cameras: Everything You Need to Know About Covert Recording, Undercover Cameras and Secret Filming Plomin Joe Hidden Cameras: Everything You Need to Know About Covert Recording, Undercover Cameras and Secret Filming 224pp £12.99 Jessica Kingsley 9781849056434 1849056439 [Formula: see text].

    Science.gov (United States)

    2016-08-01

    Last year, the Care Quality Commission issued guidance to families on using hidden cameras if they are concerned that their relatives are being abused or receiving poor care. The author was the undercover producer who exposed the abuse at Winterbourne View, near Bristol, in 2011 for BBC's Panorama. PMID:27484558

  5. Hidden Cameras: Everything You Need to Know About Covert Recording, Undercover Cameras and Secret Filming Plomin Joe Hidden Cameras: Everything You Need to Know About Covert Recording, Undercover Cameras and Secret Filming 224pp £12.99 Jessica Kingsley 9781849056434 1849056439 [Formula: see text].

    Science.gov (United States)

    2016-05-27

    LAST YEAR, the Care Quality Commission issued guidance to families on using hidden cameras if they are concerned that their relatives are being abused or receiving poor care. Filming in care settings has also resulted in high profile prosecutions, and numerous TV documentaries. Joe Plomin, the author, was the undercover producer who exposed the abuse at Winterbourne View, near Bristol, in 2011. PMID:27231069

  6. Cryogenic mechanism for ISO camera

    Science.gov (United States)

    Luciano, G.

    1987-12-01

    The Infrared Space Observatory (ISO) camera configuration, architecture, materials, tribology, motorization, and development status are outlined. The operating temperature is 2 to 3 K, at 2.5 to 18 microns. Selected material is a titanium alloy, with MoS2/TiC lubrication. A stepping motor drives the ball-bearing mounted wheels to which the optical elements are fixed. Model test results are satisfactory, and also confirm the validity of the test facilities, particularly for vibration tests at 4K.

  7. Video clustering using camera motion

    OpenAIRE

    Tort Alsina, Laura

    2012-01-01

    Com el moviment de càmera en un clip de vídeo pot ser útil per a la seva classificació en termes semàntics. [ANGLÈS] This document contains the work done in INP Grenoble during the second semester of the academic year 2011-2012, completed in Barcelona during the first months of the 2012-2013. The work presented consists in a camera motion study in different types of video in order to group fragments that have some similarity in the content. In the document it is explained how the data extr...

  8. UCXp camera imaging principle and key technologies of data post-processing

    Science.gov (United States)

    Yuan, Fangyan; Li, Guoqing; Zuo, Zhengli; Liu, Jianmin; Wu, Liang; Yu, Xiaoping; Zhao, Haitao

    2014-03-01

    The large format digital aerial camera product UCXp was introduced into the Chinese market in 2008, the image consists of 17310 columns and 11310 rows with a pixel size of 6 mm. The UCXp camera has many advantages compared with the same generation camera, with multiple lenses exposed almost at the same time and no oblique lens. The camera has a complex imaging process whose principle will be detailed in this paper. On the other hand, the UCXp image post-processing method, including data pre-processing and orthophoto production, will be emphasized in this article. Based on the data of new Beichuan County, this paper will describe the data processing and effects.

  9. Fire exposed aluminium structures

    NARCIS (Netherlands)

    Maljaars, J.; Fellinger, J.H.H.; Soetens, F.

    2006-01-01

    Material properties and mechanical response models for fire design of steel structures are based on extensive research and experience. Contrarily, the behaviour of aluminium load bearing structures exposed to fire is relatively unexplored. This article gives an overview of physical and mechanical pr

  10. Digital Mammography with a Mosaic of CCD Arrays

    Science.gov (United States)

    Jalink, Antony, Jr. (Inventor); McAdoo, James A. (Inventor)

    1998-01-01

    A digital mammography device uses a mosaic of electronic digital imaging arrays to scan an x-ray image is discussed. The mosaic of arrays is repositioned several times to expose different portions of the image, until the entire image is scanned. The data generated by the arrays during each exposure is stored in a computer. After the final exposure, the computer combines data of the several partial images to produce a composite of the original x-ray image. An aperture plate is used to reduce scatter and the overall exposure of the patient to x-rays.

  11. Strategy for the Development of a Smart NDVI Camera System for Outdoor Plant Detection and Agricultural Embedded Systems

    Directory of Open Access Journals (Sweden)

    Ali Akbar Zarezadeh

    2013-01-01

    Full Text Available The application of (smart cameras for process control, mapping, and advanced imaging in agriculture has become an element of precision farming that facilitates the conservation of fertilizer, pesticides, and machine time. This technique additionally reduces the amount of energy required in terms of fuel. Although research activities have increased in this field, high camera prices reflect low adaptation to applications in all fields of agriculture. Smart, low-cost cameras adapted for agricultural applications can overcome this drawback. The normalized difference vegetation index (NDVI for each image pixel is an applicable algorithm to discriminate plant information from the soil background enabled by a large difference in the reflectance between the near infrared (NIR and the red channel optical frequency band. Two aligned charge coupled device (CCD chips for the red and NIR channel are typically used, but they are expensive because of the precise optical alignment required. Therefore, much attention has been given to the development of alternative camera designs. In this study, the advantage of a smart one-chip camera design with NDVI image performance is demonstrated in terms of low cost and simplified design. The required assembly and pixel modifications are described, and new algorithms for establishing an enhanced NDVI image quality for data processing are discussed.

  12. Per-Pixel Coded Exposure for High-Speed and High-Resolution Imaging Using a Digital Micromirror Device Camera

    Directory of Open Access Journals (Sweden)

    Wei Feng

    2016-03-01

    Full Text Available High-speed photography is an important tool for studying rapid physical phenomena. However, low-frame-rate CCD (charge coupled device or CMOS (complementary metal oxide semiconductor camera cannot effectively capture the rapid phenomena with high-speed and high-resolution. In this paper, we incorporate the hardware restrictions of existing image sensors, design the sampling functions, and implement a hardware prototype with a digital micromirror device (DMD camera in which spatial and temporal information can be flexibly modulated. Combined with the optical model of DMD camera, we theoretically analyze the per-pixel coded exposure and propose a three-element median quicksort method to increase the temporal resolution of the imaging system. Theoretically, this approach can rapidly increase the temporal resolution several, or even hundreds, of times without increasing bandwidth requirements of the camera. We demonstrate the effectiveness of our method via extensive examples and achieve 100 fps (frames per second gain in temporal resolution by using a 25 fps camera.

  13. Per-Pixel Coded Exposure for High-Speed and High-Resolution Imaging Using a Digital Micromirror Device Camera.

    Science.gov (United States)

    Feng, Wei; Zhang, Fumin; Qu, Xinghua; Zheng, Shiwei

    2016-01-01

    High-speed photography is an important tool for studying rapid physical phenomena. However, low-frame-rate CCD (charge coupled device) or CMOS (complementary metal oxide semiconductor) camera cannot effectively capture the rapid phenomena with high-speed and high-resolution. In this paper, we incorporate the hardware restrictions of existing image sensors, design the sampling functions, and implement a hardware prototype with a digital micromirror device (DMD) camera in which spatial and temporal information can be flexibly modulated. Combined with the optical model of DMD camera, we theoretically analyze the per-pixel coded exposure and propose a three-element median quicksort method to increase the temporal resolution of the imaging system. Theoretically, this approach can rapidly increase the temporal resolution several, or even hundreds, of times without increasing bandwidth requirements of the camera. We demonstrate the effectiveness of our method via extensive examples and achieve 100 fps (frames per second) gain in temporal resolution by using a 25 fps camera. PMID:26959023

  14. Per-Pixel Coded Exposure for High-Speed and High-Resolution Imaging Using a Digital Micromirror Device Camera.

    Science.gov (United States)

    Feng, Wei; Zhang, Fumin; Qu, Xinghua; Zheng, Shiwei

    2016-03-04

    High-speed photography is an important tool for studying rapid physical phenomena. However, low-frame-rate CCD (charge coupled device) or CMOS (complementary metal oxide semiconductor) camera cannot effectively capture the rapid phenomena with high-speed and high-resolution. In this paper, we incorporate the hardware restrictions of existing image sensors, design the sampling functions, and implement a hardware prototype with a digital micromirror device (DMD) camera in which spatial and temporal information can be flexibly modulated. Combined with the optical model of DMD camera, we theoretically analyze the per-pixel coded exposure and propose a three-element median quicksort method to increase the temporal resolution of the imaging system. Theoretically, this approach can rapidly increase the temporal resolution several, or even hundreds, of times without increasing bandwidth requirements of the camera. We demonstrate the effectiveness of our method via extensive examples and achieve 100 fps (frames per second) gain in temporal resolution by using a 25 fps camera.

  15. Optimising camera traps for monitoring small mammals.

    Science.gov (United States)

    Glen, Alistair S; Cockburn, Stuart; Nichols, Margaret; Ekanayake, Jagath; Warburton, Bruce

    2013-01-01

    Practical techniques are required to monitor invasive animals, which are often cryptic and occur at low density. Camera traps have potential for this purpose, but may have problems detecting and identifying small species. A further challenge is how to standardise the size of each camera's field of view so capture rates are comparable between different places and times. We investigated the optimal specifications for a low-cost camera trap for small mammals. The factors tested were 1) trigger speed, 2) passive infrared vs. microwave sensor, 3) white vs. infrared flash, and 4) still photographs vs. video. We also tested a new approach to standardise each camera's field of view. We compared the success rates of four camera trap designs in detecting and taking recognisable photographs of captive stoats (Mustelaerminea), feral cats (Felis catus) and hedgehogs (Erinaceuseuropaeus). Trigger speeds of 0.2-2.1 s captured photographs of all three target species unless the animal was running at high speed. The camera with a microwave sensor was prone to false triggers, and often failed to trigger when an animal moved in front of it. A white flash produced photographs that were more readily identified to species than those obtained under infrared light. However, a white flash may be more likely to frighten target animals, potentially affecting detection probabilities. Video footage achieved similar success rates to still cameras but required more processing time and computer memory. Placing two camera traps side by side achieved a higher success rate than using a single camera. Camera traps show considerable promise for monitoring invasive mammal control operations. Further research should address how best to standardise the size of each camera's field of view, maximise the probability that an animal encountering a camera trap will be detected, and eliminate visible or audible cues emitted by camera traps.

  16. Camera selection for real-time in vivo radiation treatment verification systems using Cherenkov imaging

    Energy Technology Data Exchange (ETDEWEB)

    Andreozzi, Jacqueline M., E-mail: Jacqueline.M.Andreozzi.th@dartmouth.edu; Glaser, Adam K. [Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755 (United States); Zhang, Rongxiao [Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States); Jarvis, Lesley A.; Gladstone, David J. [Department of Medicine, Geisel School of Medicine and Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03766 (United States); Pogue, Brian W., E-mail: Brian.W.Pogue@dartmouth.edu [Thayer School of Engineering and Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States)

    2015-02-15

    Purpose: To identify achievable camera performance and hardware needs in a clinical Cherenkov imaging system for real-time, in vivo monitoring of the surface beam profile on patients, as novel visual information, documentation, and possible treatment verification for clinicians. Methods: Complementary metal-oxide-semiconductor (CMOS), charge-coupled device (CCD), intensified charge-coupled device (ICCD), and electron multiplying-intensified charge coupled device (EM-ICCD) cameras were investigated to determine Cherenkov imaging performance in a clinical radiotherapy setting, with one emphasis on the maximum supportable frame rate. Where possible, the image intensifier was synchronized using a pulse signal from the Linac in order to image with room lighting conditions comparable to patient treatment scenarios. A solid water phantom irradiated with a 6 MV photon beam was imaged by the cameras to evaluate the maximum frame rate for adequate Cherenkov detection. Adequate detection was defined as an average electron count in the background-subtracted Cherenkov image region of interest in excess of 0.5% (327 counts) of the 16-bit maximum electron count value. Additionally, an ICCD and an EM-ICCD were each used clinically to image two patients undergoing whole-breast radiotherapy to compare clinical advantages and limitations of each system. Results: Intensifier-coupled cameras were required for imaging Cherenkov emission on the phantom surface with ambient room lighting; standalone CMOS and CCD cameras were not viable. The EM-ICCD was able to collect images from a single Linac pulse delivering less than 0.05 cGy of dose at 30 frames/s (fps) and pixel resolution of 512 × 512, compared to an ICCD which was limited to 4.7 fps at 1024 × 1024 resolution. An intensifier with higher quantum efficiency at the entrance photocathode in the red wavelengths [30% quantum efficiency (QE) vs previous 19%] promises at least 8.6 fps at a resolution of 1024 × 1024 and lower monetary

  17. Intercomparison of SO2 camera systems for imaging volcanic gas plumes

    Science.gov (United States)

    Kern, Christoph; Lübcke, Peter; Bobrowski, Nicole; Campion, Robin; Mori, Toshiya; Smekens, Jean-François; Stebel, Kerstin; Tamburello, Giancarlo; Burton, Mike; Platt, Ulrich; Prata, Fred

    2015-07-01

    SO2 camera systems are increasingly being used to image volcanic gas plumes. The ability to derive SO2 emission rates directly from the acquired imagery at high time resolution allows volcanic process studies that incorporate other high time-resolution datasets. Though the general principles behind the SO2 camera have remained the same for a number of years, recent advances in CCD technology and an improved understanding of the physics behind the measurements have driven a continuous evolution of the camera systems. Here we present an intercomparison of seven different SO2 cameras. In the first part of the experiment, the various technical designs are compared and the advantages and drawbacks of individual design options are considered. Though the ideal design was found to be dependent on the specific application, a number of general recommendations are made. Next, a time series of images recorded by all instruments at Stromboli Volcano (Italy) is compared. All instruments were easily able to capture SO2 clouds emitted from the summit vents. Quantitative comparison of the SO2 load in an individual cloud yielded an intra-instrument precision of about 12%. From the imagery, emission rates were then derived according to each group's standard retrieval process. A daily average SO2 emission rate of 61 ± 10 t/d was calculated. Due to differences in spatial integration methods and plume velocity determination, the time-dependent progression of SO2 emissions varied significantly among the individual systems. However, integration over distinct degassing events yielded comparable SO2 masses. Based on the intercomparison data, we find an approximate 1-sigma precision of 20% for the emission rates derived from the various SO2 cameras. Though it may still be improved in the future, this is currently within the typical accuracy of the measurement and is considered sufficient for most applications.

  18. Intercomparison of SO2 camera systems for imaging volcanic gas plumes

    Science.gov (United States)

    Kern, Christoph; Lübcke, Peter; Bobrowski, Nicole; Campion, Robin; Mori, Toshiya; Smekens, Jean-Francois; Stebel, Kerstin; Tamburello, Giancarlo; Burton, Mike; Platt, Ulrich; Prata, Fred

    2015-01-01

    SO2 camera systems are increasingly being used to image volcanic gas plumes. The ability to derive SO2 emission rates directly from the acquired imagery at high time resolution allows volcanic process studies that incorporate other high time-resolution datasets. Though the general principles behind the SO2 camera have remained the same for a number of years, recent advances in CCD technology and an improved understanding of the physics behind the measurements have driven a continuous evolution of the camera systems. Here we present an intercomparison of seven different SO2 cameras. In the first part of the experiment, the various technical designs are compared and the advantages and drawbacks of individual design options are considered. Though the ideal design was found to be dependent on the specific application, a number of general recommendations are made. Next, a time series of images recorded by all instruments at Stromboli Volcano (Italy) is compared. All instruments were easily able to capture SO2 clouds emitted from the summit vents. Quantitative comparison of the SO2 load in an individual cloud yielded an intra-instrument precision of about 12%. From the imagery, emission rates were then derived according to each group's standard retrieval process. A daily average SO2 emission rate of 61 ± 10 t/d was calculated. Due to differences in spatial integration methods and plume velocity determination, the time-dependent progression of SO2 emissions varied significantly among the individual systems. However, integration over distinct degassing events yielded comparable SO2 masses. Based on the intercomparison data, we find an approximate 1-sigma precision of 20% for the emission rates derived from the various SO2 cameras. Though it may still be improved in the future, this is currently within the typical accuracy of the measurement and is considered sufficient for most applications.

  19. Family Of Calibrated Stereometric Cameras For Direct Intraoral Use

    Science.gov (United States)

    Curry, Sean; Moffitt, Francis; Symes, Douglas; Baumrind, Sheldon

    1983-07-01

    In order to study empirically the relative efficiencies of different types of orthodontic appliances in repositioning teeth in vivo, we have designed and constructed a pair of fixed-focus, normal case, fully-calibrated stereometric cameras. One is used to obtain stereo photography of single teeth, at a scale of approximately 2:1, and the other is designed for stereo imaging of the entire dentition, study casts, facial structures, and other related objects at a scale of approximately 1:8. Twin lenses simultaneously expose adjacent frames on a single roll of 70 mm film. Physical flatness of the film is ensured by the use of a spring-loaded metal pressure plate. The film is forced against a 3/16" optical glass plate upon which is etched an array of 16 fiducial marks which divide the film format into 9 rectangular regions. Using this approach, it has been possible to produce photographs which are undistorted for qualitative viewing and from which quantitative data can be acquired by direct digitization of conventional photographic enlargements. We are in the process of designing additional members of this family of cameras. All calibration and data acquisition and analysis techniques previously developed will be directly applicable to these new cameras.

  20. Digging supplementary buried channels: investigating the notch architecture within the CCD pixels on ESA's Gaia satellite

    CERN Document Server

    Seabroke, G M; Murray, N J; Crowley, C; Hopkinson, G; Brown, A G A; Kohley, R; Holland, A

    2013-01-01

    The European Space Agency (ESA) Gaia satellite has 106 CCD image sensors which will suffer from increased charge transfer inefficiency (CTI) as a result of radiation damage. To aid the mitigation at low signal levels, the CCD design includes Supplementary Buried Channels (SBCs, otherwise known as `notches') within each CCD column. We present the largest published sample of Gaia CCD SBC Full Well Capacity (FWC) laboratory measurements and simulations based on 13 devices. We find that Gaia CCDs manufactured post-2004 have SBCs with FWCs in the upper half of each CCD that are systematically smaller by two orders of magnitude (<50 electrons) compared to those manufactured pre-2004 (thousands of electrons). Gaia's faint star (13 < G < 20 mag) astrometric performance predictions by Prod'homme et al. and Holl et al. use pre-2004 SBC FWCs as inputs to their simulations. However, all the CCDs already integrated onto the satellite for the 2013 launch are post-2004. SBC FWC measurements are not available for on...

  1. A new segmentation algorithm for lunar surface terrain based on CCD images

    Science.gov (United States)

    Jiang, Hong-Kun; Tian, Xiao-Lin; Xu, Ao-Ao

    2015-09-01

    Terrain classification is one of the critical steps used in lunar geomorphologic analysis and landing site selection. Most of the published works have focused on a Digital Elevation Model (DEM) to distinguish different regions of lunar terrain. This paper presents an algorithm that can be applied to lunar CCD images by blocking and clustering according to image features, which can accurately distinguish between lunar highland and lunar mare. The new algorithm, compared with the traditional algorithm, can improve classification accuracy. The new algorithm incorporates two new features and one Tamura texture feature. The new features are generating an enhanced image histogram and modeling the properties of light reflection, which can represent the geological characteristics based on CCD gray level images. These features are applied to identify texture in order to perform image clustering and segmentation by a weighted Euclidean distance to distinguish between lunar mare and lunar highlands. The new algorithm has been tested on Chang'e-1 CCD data and the testing result has been compared with geological data published by the U.S. Geological Survey. The result has shown that the algorithm can effectively distinguish the lunar mare from highlands in CCD images. The overall accuracy of the proposed algorithm is satisfactory, and the Kappa coefficient is 0.802, which is higher than the result of combining the DEM with CCD images.

  2. Action selection for single-camera SLAM

    OpenAIRE

    Vidal-Calleja, Teresa A.; Sanfeliu, Alberto; Andrade-Cetto, J

    2010-01-01

    A method for evaluating, at video rate, the quality of actions for a single camera while mapping unknown indoor environments is presented. The strategy maximizes mutual information between measurements and states to help the camera avoid making ill-conditioned measurements that are appropriate to lack of depth in monocular vision systems. Our system prompts a user with the appropriate motion commands during 6-DOF visual simultaneous localization and mapping with a handheld camera. Additionall...

  3. Development of biostereometric experiments. [stereometric camera system

    Science.gov (United States)

    Herron, R. E.

    1978-01-01

    The stereometric camera was designed for close-range techniques in biostereometrics. The camera focusing distance of 360 mm to infinity covers a broad field of close-range photogrammetry. The design provides for a separate unit for the lens system and interchangeable backs on the camera for the use of single frame film exposure, roll-type film cassettes, or glass plates. The system incorporates the use of a surface contrast optical projector.

  4. Movement-based Interaction in Camera Spaces

    DEFF Research Database (Denmark)

    Eriksson, Eva; Riisgaard Hansen, Thomas; Lykke-Olesen, Andreas

    2006-01-01

    In this paper we present three concepts that address movement-based interaction using camera tracking. Based on our work with several movement-based projects we present four selected applications, and use these applications to leverage our discussion, and to describe our three main concepts space......, relations, and feedback. We see these as central for describing and analysing movement-based systems using camera tracking and we show how these three concepts can be used to analyse other camera tracking applications....

  5. Review of ULTRANAC high-speed camera: applications, results, and techniques

    Science.gov (United States)

    Lawrence, Brett R.

    1997-05-01

    The ULTRANAC Ultra-High Speed Framing and Streak Camera System, from Imco Electro-Optics Limited of England was first presented to the market at the 19th ICHSPP held in Cambridge, England, in 1990. It was the world's first fully computerized image converter camera and is capable of remote programming at framing speeds up to 20 million fps and streak speeds up to 1 nS/mm. The delay, exposure, interframe and output trigger times can be independently programmed within any one sequence. Increased spatial resolution is obtained by generating a series of static frames during the exposure period as opposed to the previously utilized sine wave shuttering technique. The first ULTRANAC was supplied to Japan, through the parent company, NAC, in 1991. Since then, more than 40 cameras have been installed world-wide. The range of applications is many and varied covering impact studies, shock wave research, high voltage discharge, ballistics, detonics, laser and plasma effects, combustion and injection research, nuclear and particle studies, crack propagation and ink jet printer development among many others. This paper attempts to present the results obtained from such tests. It will describe the methods of recording the images, both film and electronically, and recent advances in cooled CCD image technology and associated software analysis programs.

  6. The SLcam: A full-field energy dispersive X-ray camera

    CERN Document Server

    Bjeoumikhov, A; Langhoff, N; Ordavo, I; Radtke, M; Reinholz, U; Riesemeier, H; Scharf, O; Soltau, H; Wedell, R

    2012-01-01

    The color X-ray camera (SLcam) is a full-field single photon imager. As stand-alone camera, it is applicable for energy and space-resolved X-ray detection measurements. The exchangeable poly-capillary optics in front of a beryllium entrance window conducts X-ray photons from the probe to distinguished energy dispersive pixels on a pnCCD. The dedicated software enables the acquisition and the online processing of the spectral data for all 69696 pixels, leading to a real-time visualization of the element distribution in a sample. No scanning system is employed. A first elemental composition image of the sample is visible within minutes while statistics is improving in the course of time. Straight poly-capillary optics allows for 1:1 imaging with a space resolution of 50 um and no limited depth of sharpness, ideal to map uneven objects. Using conically shaped optics, a magnification of 6 times was achieved with a space resolution of 10 um. We present a measurement with a laboratory source showing the camera capa...

  7. Comparative evaluation of consumer grade cameras and mobile phone cameras for close range photogrammetry

    Science.gov (United States)

    Chikatsu, Hirofumi; Takahashi, Yoji

    2009-08-01

    The authors have been concentrating on developing convenient 3D measurement methods using consumer grade digital cameras, and it was concluded that consumer grade digital cameras are expected to become a useful photogrammetric device for the various close range application fields. On the other hand, mobile phone cameras which have 10 mega pixels were appeared on the market in Japan. In these circumstances, we are faced with alternative epoch-making problem whether mobile phone cameras are able to take the place of consumer grade digital cameras in close range photogrammetric applications. In order to evaluate potentials of mobile phone cameras in close range photogrammetry, comparative evaluation between mobile phone cameras and consumer grade digital cameras are investigated in this paper with respect to lens distortion, reliability, stability and robustness. The calibration tests for 16 mobile phone cameras and 50 consumer grade digital cameras were conducted indoors using test target. Furthermore, practability of mobile phone camera for close range photogrammetry was evaluated outdoors. This paper presents that mobile phone cameras have ability to take the place of consumer grade digital cameras, and develop the market in digital photogrammetric fields.

  8. True-color night vision cameras

    Science.gov (United States)

    Kriesel, Jason; Gat, Nahum

    2007-04-01

    This paper describes True-Color Night Vision cameras that are sensitive to the visible to near-infrared (V-NIR) portion of the spectrum allowing for the "true-color" of scenes and objects to be displayed and recorded under low-light-level conditions. As compared to traditional monochrome (gray or green) night vision imagery, color imagery has increased information content and has proven to enable better situational awareness, faster response time, and more accurate target identification. Urban combat environments, where rapid situational awareness is vital, and marine operations, where there is inherent information in the color of markings and lights, are example applications that can benefit from True-Color Night Vision technology. Two different prototype cameras, employing two different true-color night vision technological approaches, are described and compared in this paper. One camera uses a fast-switching liquid crystal filter in front of a custom Gen-III image intensified camera, and the second camera is based around an EMCCD sensor with a mosaic filter applied directly to the sensor. In addition to visible light, both cameras utilize NIR to (1) increase the signal and (2) enable the viewing of laser aiming devices. The performance of the true-color cameras, along with the performance of standard (monochrome) night vision cameras, are reported and compared under various operating conditions in the lab and the field. In addition to subjective criterion, figures of merit designed specifically for the objective assessment of such cameras are used in this analysis.

  9. Research of Camera Calibration Based on DSP

    OpenAIRE

    Zheng Zhang; Yukun Wan; Lixin Cai

    2013-01-01

    To take advantage of the high-efficiency and stability of DSP in the data processing and the functions of OpenCV library, this study brought forward a scheme that camera calibration in DSP embedded system calibration. An arithmetic of camera calibration based on OpenCV is designed by analyzing the camera model and lens distortion. The transplantation of EMCV to DSP is completed and the arithmetic of camera calibration is migrated and optimized based on the CCS development environment and the ...

  10. Omnidirectional Underwater Camera Design and Calibration

    Directory of Open Access Journals (Sweden)

    Josep Bosch

    2015-03-01

    Full Text Available This paper presents the development of an underwater omnidirectional multi-camera system (OMS based on a commercially available six-camera system, originally designed for land applications. A full calibration method is presented for the estimation of both the intrinsic and extrinsic parameters, which is able to cope with wide-angle lenses and non-overlapping cameras simultaneously. This method is valid for any OMS in both land or water applications. For underwater use, a customized housing is required, which often leads to strong image distortion due to refraction among the different media. This phenomena makes the basic pinhole camera model invalid for underwater cameras, especially when using wide-angle lenses, and requires the explicit modeling of the individual optical rays. To address this problem, a ray tracing approach has been adopted to create a field-of-view (FOV simulator for underwater cameras. The simulator allows for the testing of different housing geometries and optics for the cameras to ensure a complete hemisphere coverage in underwater operation. This paper describes the design and testing of a compact custom housing for a commercial off-the-shelf OMS camera (Ladybug 3 and presents the first results of its use. A proposed three-stage calibration process allows for the estimation of all of the relevant camera parameters. Experimental results are presented, which illustrate the performance of the calibration method and validate the approach.

  11. Framework for Evaluating Camera Opinions

    Directory of Open Access Journals (Sweden)

    K.M. Subramanian

    2015-03-01

    Full Text Available Opinion mining plays a most important role in text mining applications in brand and product positioning, customer relationship management, consumer attitude detection and market research. The applications lead to new generation of companies/products meant for online market perception, online content monitoring and reputation management. Expansion of the web inspires users to contribute/express opinions via blogs, videos and social networking sites. Such platforms provide valuable information for analysis of sentiment pertaining a product or service. This study investigates the performance of various feature extraction methods and classification algorithm for opinion mining. Opinions expressed in Amazon website for cameras are collected and used for evaluation. Features are extracted from the opinions using Term Document Frequency and Inverse Document Frequency (TDFIDF. Feature transformation is achieved through Principal Component Analysis (PCA and kernel PCA. Naïve Bayes, K Nearest Neighbor and Classification and Regression Trees (CART classification algorithms classify the features extracted.

  12. HRSC: High resolution stereo camera

    Science.gov (United States)

    Neukum, G.; Jaumann, R.; Basilevsky, A.T.; Dumke, A.; Van Gasselt, S.; Giese, B.; Hauber, E.; Head, J. W.; Heipke, C.; Hoekzema, N.; Hoffmann, H.; Greeley, R.; Gwinner, K.; Kirk, R.; Markiewicz, W.; McCord, T.B.; Michael, G.; Muller, Jan-Peter; Murray, J.B.; Oberst, J.; Pinet, P.; Pischel, R.; Roatsch, T.; Scholten, F.; Willner, K.

    2009-01-01

    The High Resolution Stereo Camera (HRSC) on Mars Express has delivered a wealth of image data, amounting to over 2.5 TB from the start of the mapping phase in January 2004 to September 2008. In that time, more than a third of Mars was covered at a resolution of 10-20 m/pixel in stereo and colour. After five years in orbit, HRSC is still in excellent shape, and it could continue to operate for many more years. HRSC has proven its ability to close the gap between the low-resolution Viking image data and the high-resolution Mars Orbiter Camera images, leading to a global picture of the geological evolution of Mars that is now much clearer than ever before. Derived highest-resolution terrain model data have closed major gaps and provided an unprecedented insight into the shape of the surface, which is paramount not only for surface analysis and geological interpretation, but also for combination with and analysis of data from other instruments, as well as in planning for future missions. This chapter presents the scientific output from data analysis and highlevel data processing, complemented by a summary of how the experiment is conducted by the HRSC team members working in geoscience, atmospheric science, photogrammetry and spectrophotometry. Many of these contributions have been or will be published in peer-reviewed journals and special issues. They form a cross-section of the scientific output, either by summarising the new geoscientific picture of Mars provided by HRSC or by detailing some of the topics of data analysis concerning photogrammetry, cartography and spectral data analysis.

  13. MISR FIRSTLOOK radiometric camera-by-camera Cloud Mask V001

    Data.gov (United States)

    National Aeronautics and Space Administration — This file contains the FIRSTLOOK Radiometric camera-by-camera Cloud Mask (RCCM) dataset produced using ancillary inputs (RCCT) from the previous time period. It is...

  14. A study of a multi-pinned phase CCD detector for use as a star tracker

    Science.gov (United States)

    Friedman, Scott D.

    1994-01-01

    This grant has supported studies of the use of charge coupled devices (CCD's) in star trackers in a number of different areas. Among the tasks we have pursued are the following: (1) radiation modeling and the increase in noise equivalent angle as a result of exposure to protons and bremsstrahlung gamma rays; (2) the development of pattern matching software to identify field locations from a CCD image and a pre-existing map of the local area; (3) observations of various stellar fields from the 24 inch telescope at the Offit Observatory at JHU, primarily to test the pattern matching software (these included crowded fields as well as moving objects, like comets); and (4) tracking of very faint objects to determine the faint limit of the CCD system.

  15. Direct detection of x-rays for protein crystallography employing a thick, large area CCD

    Science.gov (United States)

    Atac, Muzaffer; McKay, Timothy

    1999-01-01

    An apparatus and method for directly determining the crystalline structure of a protein crystal. The crystal is irradiated by a finely collimated x-ray beam. The interaction of the x-ray beam with the crystal produces scattered x-rays. These scattered x-rays are detected by means of a large area, thick CCD which is capable of measuring a significant number of scattered x-rays which impact its surface. The CCD is capable of detecting the position of impact of the scattered x-ray on the surface of the CCD and the quantity of scattered x-rays which impact the same cell or pixel. This data is then processed in real-time and the processed data is outputted to produce a image of the structure of the crystal. If this crystal is a protein the molecular structure of the protein can be determined from the data received.

  16. Signal Detection of Multi-Channel Capillary Electrophoresis Chip Based on CCD

    Science.gov (United States)

    Lv, Hongfeng; Yan, Weiping; Yang, Xiaobo; Li, Jiechao; Zhu, Jieying

    2012-12-01

    A kind of multi-channel capillary electrophoresis (CE) chip signal detection system based on CCD was developed. The output signal of the CCD sensor was processed by a series of pre-processing circuits and ADC, and then it was collected by the Field Programmable Gate Array (FPGA) chip which communicated with a host computer. The core in FPGA was designed to control the signal flow of the CCD and transfer the data to PC based on a Nios II embedded soft-processor. The application of PC was used to store the data and demonstrate the curve. The measurement of the fluorescent signals for different concentration Rhodamine B dyes is presented and the comparison with other detection systems is also discussed.

  17. Super CCD EXR技术运用到长焦机型

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    相比普通的影像传感器,Super CCD EXR光线信号的采集效率得到了大幅提升,从而有效地提升了成像质量,特别是明显提高了高感光度下的性噪比,其性能在首款采用Super CCD EXR的富士FinePix F200EXR相机上得到了充分证明。富士FinePix F75EXR和富士FinePix S205EXR因为采用了富士公司当前的看家法宝——Super CCD EXR技术,所以受到广泛的关注。

  18. Modelling electron distributions within ESA's Gaia satellite CCD pixels to mitigate radiation damage

    CERN Document Server

    Seabroke, G M; Burt, D; Robbins, M S

    2009-01-01

    The Gaia satellite is a high-precision astrometry, photometry and spectroscopic ESA cornerstone mission, currently scheduled for launch in 2012. Its primary science drivers are the composition, formation and evolution of the Galaxy. Gaia will achieve its unprecedented positional accuracy requirements with detailed calibration and correction for radiation damage. At L2, protons cause displacement damage in the silicon of CCDs. The resulting traps capture and emit electrons from passing charge packets in the CCD pixel, distorting the image PSF and biasing its centroid. Microscopic models of Gaia's CCDs are being developed to simulate this effect. The key to calculating the probability of an electron being captured by a trap is the 3D electron density within each CCD pixel. However, this has not been physically modelled for the Gaia CCD pixels. In Seabroke, Holland & Cropper (2008), the first paper of this series, we motivated the need for such specialised 3D device modelling and outlined how its future resu...

  19. A fast CCD vertex detector for the future linear collider: some recent developments

    CERN Document Server

    Gillman, A R

    2001-01-01

    Experiments at a future e sup + e sup - linear collider will require a high-performance vertex detector to identify heavy quarks in multi-jet final states. The SLD experiment at SLAC has successfully demonstrated that charge-coupled devices (CCDs) are ideal candidates for this role, offering excellent two-dimensional spatial resolution with extremely low mass.This paper discusses recent R and D studies aimed at further reducing the vertex detector material budget and significantly increasing the CCD readout speed, in order to extend the physics reach of the future linear collider. A radical new CCD architecture is described, which would enable a CCD-based vertex detector to be used in the extremely challenging environment of the superconducting TESLA collider.

  20. Fast Data Acquisition for X-ray CCD 165 SX Detector%X -ray CCD165-SX 探测器快速数据采集

    Institute of Scientific and Technical Information of China (English)

    柳义; 周平

    2014-01-01

    对X光探测器X-ray CCD165-SX在帧移模式下进行数据采集。选择合适开口高度的掩膜,使得CCD的曝光面仅是整个探测面的一小部份。利用TTL信号发生器产生的脉冲信号触发子潜像帧移,将各个不同时间内产生的子潜像储存在CCD的芯片上不同位置上,当芯片填满子潜像时,一次性读出。这种方式大大加快了实验数据的采集速度。实验中对快速升温的情况下对PE样品进行测试,成功地采集到了随时间快速变化的散射信号。%By installation of the mask with adjustable opening size and TTL generator ,X-ray Scattering data is collected by X-ray CCD 165 SX under Frameshift mode .In the process ,exposure area is onlysmall part of the detecting area of the CCD and sub -images produced at difference times are frame shifted by TTL trigger to difference parts on CCD chip subsequently .All the sub-images are read out at once until the chip reaches full-ness of sub -images.This approach greatly increases the data collection speed .Finally,we use PE as the sam-ple in fast temperature rising environment for the fast data acquisition measurement and successful ly collected the scattering data which changed with times .