WorldWideScience

Sample records for bent optical-fiber sensor

  1. In-situ growth of AuNPs on WS2@U-bent optical fiber for evanescent wave absorption sensor

    Science.gov (United States)

    Zhang, Suzhen; Zhao, Yuefeng; Zhang, Chao; Jiang, Shouzhen; Yang, Cheng; Xiu, Xianwu; Li, Chonghui; Li, Zhen; Zhao, Xiaofei; Man, Baoyuan

    2018-05-01

    The sensitivity of the evanescent wave absorption sensor is always a hot topic which has been attracted researchers' discussion. It is still a challenge for developing the effective sensor to sensitively detect some biochemical molecules solution in a simple and low-cost way. In this paper, an evanescent wave absorption (EWA) sensor has been presented based on the U-bent multimode fiber coated with tungsten disulfide (WS2) film and in-situ growth of gold nanoparticles (AuNPs) for the detection of ethanol solution and sodium chloride (NaCl) solution. Benefitted from the effective light coupling produced between U-bent probe and AuNPs, we attained the optimal size of the AuNPs by changing the reaction time between WS2 and tetrachloroauric acid (HAuCl4). With the AuNPs/WS2@U-bent optical fiber, we discussed the behaviors of EWA sensor, such as sensitivity, reproducibility, fast response-recovery time and stability. The sensitivity (△A/△C) of the proposed AuNPs/WS2@U-bent optical fiber EWA sensor is 0.65 for the detection of the ethanol solution. Besides, the AuNPs/WS2@U-bent optical fiber EWA sensor exhibits high sensitivity in detection of the sodium chloride (NaCl), which can reach 1.5 when the proposed sensor was immersed into NaCl solution. Our work demonstrates that the U-bent optical fiber EWA sensor may have promising applications in testing the solution of concentration.

  2. CO2 laser ablation of bent optical fibers for sensing applications

    International Nuclear Information System (INIS)

    Lévesque, L; Jdanov, V

    2011-01-01

    A procedure for the fabrication of a fiber optic sensor involving CO 2 laser ablation at λ = 10.6 µm is proposed. A basic system to achieve optical fiber bending and material processing on a single mode optical fiber is described and it is demonstrated that an optical fiber can be bent at a very precise angle by focusing a CO 2 beam locally near the glass cladding surface until it reaches melting temperature. A method is also described for removing material at the apex of a bent fiber to obtain a smooth and well flattened plane surface that is suitable for optical fiber sensing

  3. Introduction to optical fiber sensors

    International Nuclear Information System (INIS)

    Moukdad, S.

    1991-01-01

    Optical fiber sensors have many advantages over other types of sensors, for example: Low weight, immunity from EMI, electrical isolation, chemical passivity, and high sensitivity. In this seminar, a brief explanation of the optical fiber sensors, their use, and their advantages will be given. After, a description of the main optical fiber sensor components will be presented. Principles of some kinds of optical fiber sensors will be presented, and the principle of the fiber-optic rotation sensor and its realization will be discussed in some details, as well as its main applications. (author). 5 refs, 8 figs, 2 tabs

  4. Improved Optical Fiber Chemical Sensors

    Science.gov (United States)

    Egalon, Claudio O.; Rogowski, Robert S.

    1994-01-01

    Calculations, based on exact theory of optical fiber, have shown how to increase optical efficiency sensitivity of active-core, step-index-profile optical-fiber fluorosensor. Calculations result of efforts to improve efficiency of optical-fiber chemical sensor of previous concept described in "Making Optical-Fiber Chemical Sensors More Sensitive" (LAR-14525). Optical fiber chemical detector of enhanced sensitivity made in several configurations. Portion of fluorescence or chemiluminescence generated in core, and launched directly into bound electromagnetic modes that propagate along core to photodetector.

  5. Optical fiber powered pressure sensor

    International Nuclear Information System (INIS)

    Schweizer, P.; Neveux, L.; Ostrowsky, D.B.

    1987-01-01

    In the system described, a pressure sensor and its associated electronics are optically powered by a 20 mw laser and a photovoltaic cell via an optical fiber. The sensor is periodically interrogated and sends the measures obtained back to the central unit using an LED and a second fiber. The results obtained as well as the expected evolution will be described

  6. Monitoring of Moisture in Transformer Oil Using Optical Fiber as Sensor

    OpenAIRE

    S. Laskar; S. Bordoloi

    2013-01-01

    This paper describes an optical fiber sensor and temperature sensor-based instrumentation system to measure the moisture content in transformer oil. The sensor system consists of (i) Diode Laser Source, (ii) a bare and bent multimode fiber as sensor probe, (iii) an LDR as detector, (iv) LM35-based temperature sensor, and (v) microcontroller system having a trained ANN for processing and calibration. The bare and bent optical fiber sensor and the temperature sensor LM35 are used to provide the...

  7. Optical Fiber Grating based Sensors

    DEFF Research Database (Denmark)

    Michelsen, Susanne

    2003-01-01

    In this thesis differenct optical fiber gratings are used for sensor purposes. If a fiber with a core concentricity error (CCE) is used, a directional dependent bend sensor can be produced. The CCE direction can be determined by means of diffraction. This makes it possible to produce long......-period gratings in a fiber with a CCE direction parallel or perpendicular to the writing direction. The maximal bending sensitivity is independent on the writing direction, but the detailed bending response is different in the two cases. A temperature and strain sensor, based on a long-period grating and two...... sampled gratings, was produced and investigated. It is based on the different temperature and strain response of these gratings. Both a transfer matrix method and an overlap calculation is performed to explain the sensor response. Another type of sensor is based on tuning and modulation of a laser...

  8. Optical Fiber Grating Hydrogen Sensors: A Review.

    Science.gov (United States)

    Dai, Jixiang; Zhu, Li; Wang, Gaopeng; Xiang, Feng; Qin, Yuhuan; Wang, Min; Yang, Minghong

    2017-03-12

    In terms of hydrogen sensing and detection, optical fiber hydrogen sensors have been a research issue due to their intrinsic safety and good anti-electromagnetic interference. Among these sensors, hydrogen sensors consisting of fiber grating coated with sensitive materials have attracted intensive research interests due to their good reliability and distributed measurements. This review paper mainly focuses on optical fiber hydrogen sensors associated with fiber gratings and various materials. Their configurations and sensing performances proposed by different groups worldwide are reviewed, compared and discussed in this paper. Meanwhile, the challenges for fiber grating hydrogen sensors are also addressed.

  9. Optical fiber sensors for harsh environments

    Science.gov (United States)

    Xu, Juncheng; Wang, Anbo

    2007-02-06

    A diaphragm optic sensor comprises a ferrule including a bore having an optical fiber disposed therein and a diaphragm attached to the ferrule, the diaphragm being spaced apart from the ferrule to form a Fabry-Perot cavity. The cavity is formed by creating a pit in the ferrule or in the diaphragm. The components of the sensor are preferably welded together, preferably by laser welding. In some embodiments, the entire ferrule is bonded to the fiber along the entire length of the fiber within the ferrule; in other embodiments, only a portion of the ferrule is welded to the fiber. A partial vacuum is preferably formed in the pit. A small piece of optical fiber with a coefficient of thermal expansion chosen to compensate for mismatches between the main fiber and ferrule may be spliced to the end of the fiber.

  10. Development of an optical fiber flow velocity sensor.

    Science.gov (United States)

    Harada, Toshio; Kamoto, Kenji; Abe, Kyutaro; Izumo, Masaki

    2009-01-01

    A new optical fiber flow velocity sensor was developed by using an optical fiber information network system in sewer drainage pipes. The optical fiber flow velocity sensor operates without electric power, and the signals from the sensor can be transmitted over a long distance through the telecommunication system in the optical fiber network. Field tests were conducted to check the performance of the sensor in conduits in the pumping station and sewage pond managed by the Tokyo Metropolitan Government. Test results confirmed that the velocity sensor can be used for more than six months without any trouble even in sewer drainage pipes.

  11. Recovering Signals from Optical Fiber Interferometric Sensors

    Science.gov (United States)

    1991-06-01

    electronic functions to be combined onto a single -integrated circuit on- a silicon (or other) substrate. These custom -designed circuits are known by...largely unknown to the ordinary :itizen and seldom mentioned in the- popular press. Yet optical fiber sensors have attracted considerable- interest...write the-power in output leg I by performing the same interchange on Equation (95). a3(L) 12 {2B 2B1 -cos(3KL)I + B3B;[5+4cos(3KL)] 2 18 - B2B ;e(4-"?1 +e

  12. Noninvasive blood pressure measurement scheme based on optical fiber sensor

    Science.gov (United States)

    Liu, Xianxuan; Yuan, Xueguang; Zhang, Yangan

    2016-10-01

    Optical fiber sensing has many advantages, such as volume small, light quality, low loss, strong in anti-jamming. Since the invention of the optical fiber sensing technology in 1977, optical fiber sensing technology has been applied in the military, national defense, aerospace, industrial, medical and other fields in recent years, and made a great contribution to parameter measurement in the environment under the limited condition .With the rapid development of computer, network system, the intelligent optical fiber sensing technology, the sensor technology, the combination of computer and communication technology , the detection, diagnosis and analysis can be automatically and efficiently completed. In this work, we proposed a noninvasive blood pressure detection and analysis scheme which uses optical fiber sensor. Optical fiber sensing system mainly includes the light source, optical fiber, optical detector, optical modulator, the signal processing module and so on. wavelength optical signals were led into the optical fiber sensor and the signals reflected by the human body surface were detected. By comparing actual testing data with the data got by traditional way to measure the blood pressure we can establish models for predicting the blood pressure and achieve noninvasive blood pressure measurement by using spectrum analysis technology. Blood pressure measurement method based on optical fiber sensing system is faster and more convenient than traditional way, and it can get accurate analysis results in a shorter period of time than before, so it can efficiently reduce the time cost and manpower cost.

  13. Optical fiber sensors for medical applications: practical engineering considerations

    NARCIS (Netherlands)

    Heijmans, J.A.C.; Cheng, L.K.; Wieringa, F.P.

    2008-01-01

    The advantages of optical fibers as medical sensors are recognized world wide nowadays. Insensitivity to electromagnetic disturbances and relative small dimensions are the most well known properties. The advantages of fiber optic sensors are especially valuable within environments with high

  14. Polymer optical fiber bragg grating sensors

    DEFF Research Database (Denmark)

    Stefani, Alessio; Yuan, Scott Wu; Andresen, Søren

    2010-01-01

    Fiber-optical accelerometers based on polymer optical fiber Bragg gratings are reported. We have written fiber Bragg gratings for 1550 nm and 850 nm operations, characterized their temperature and strain response, and tested their performance in a prototype accelerometer....

  15. Detection of Cadmium Ion by Evanescent Wave Based Chitosan Coated Optical Fiber Sensor

    International Nuclear Information System (INIS)

    Yulianti, I; Edy, S S; Saputra, B A; Aji, M P; Susanto; Kurdi, O

    2017-01-01

    Evanescent wave based-optical fiber sensor to detect cadmium ion is proposed. Chitosan was used by using the dip-coating method. The sensor was fabricated in U-bent shape. U-bent optical sensor at aconcentration of 2ppm and 5ppm had asensitivity of 0.2067 dBm/ppm and -0.7995 dBm/ppm, respectively. At a level of 2ppm - 5ppm, the optical sensor has a linear response with asensitivity of -0.283 dBm/ppm. The sensor takes 9.5 minutes to reach steady stateat aconcentration of 1 ppm. Atalevel of 2ppm - 5ppm, the sensor takes 5 minutes to 10.45 minutes to reach steady state. (paper)

  16. Design of Oil Viscosity Sensor Based on Plastic Optical Fiber

    Science.gov (United States)

    Yunus, Muhammad; Arifin, A.

    2018-03-01

    A research of plastic optical fiber based sensors have been studied for measurement of oil viscosity. This sensor was made with straight configuration, U configuration, and gamma configuration have two types, there are optical fiber sensor with cladding and without cladding. Viscosity sensor was made, dipped into an oil sample with a concentration of viscosity percentage about 270 mPa.s - 350 mPa.s. The light from the LED propagated into the optical fiber, then it was received by the photodetector converted to output power. When plastic optical fiber dipped into an oil sample, viscosity of oil affect increase of refractive index on optical fiber resulting in a bigger loss of power so the light intensity will be smaller, consequences the measured output power will be smaller. Sensitivity and resolution viscosity sensor without cladding peel showed the best result rather than viscosity sensor with cladding peel. The best result in the measurement showed in gamma configuration with 3 cm length of cladding peel and the diameter of bending 0,25 cm is the range 103,090 nWatt, sensitivity 1,289 nWatt/mPa.s, and resolution 0,776 mPa.s. This method is effectively and efficiently used as an oil viscosity sensor with high sensitivity and resolution.

  17. Microstructured optical fiber refractive index sensor

    DEFF Research Database (Denmark)

    Town, Graham E.; McCosker, Ravi; Yuan, Scott Wu

    2010-01-01

    We describe a dual-core microstructured optical fiber designed for refractive index sensing of fluids. We show that by using the exponential dependence of intercore coupling on analyte refractive index, both large range and high sensitivity can be achieved in the one device. We also show...

  18. Optical fibers and sensors for chemistry

    International Nuclear Information System (INIS)

    Perez, J.J.; Boisde, G.

    1988-01-01

    The idea of using optical fibers in nuclear environment occurs as soon as 1967, too soon for practical realizations. In 1973 the first glass fibers were made available in Switzerland. From 1973 to 1988 three periods show the development: conception from 1973 to 1978, technique strengthening from 1978 to 1983 and nuclear and non nuclear industrial development since 1983. 45 refs., 27 figs [fr

  19. Optical Fiber Sensors Based on Fiber Ring Laser Demodulation Technology.

    Science.gov (United States)

    Xie, Wen-Ge; Zhang, Ya-Nan; Wang, Peng-Zhao; Wang, Jian-Zhang

    2018-02-08

    A review for optical fiber sensors based on fiber ring laser (FRL) demodulation technology is presented. The review focuses on the principles, main structures, and the sensing performances of different kinds of optical fiber sensors based on FRLs. First of all, the theory background of the sensors has been discussed. Secondly, four different types of sensors are described and compared, which includes Mach-Zehnder interferometer (MZI) typed sensors, Fabry-Perot interferometer (FPI) typed sensors, Sagnac typed sensors, and fiber Bragg grating (FBG) typed sensors. Typical studies and main properties of each type of sensors are presented. Thirdly, a comparison of different types of sensors are made. Finally, the existing problems and future research directions are pointed out and analyzed.

  20. Optical fiber sensors for IoT and smart devices

    CERN Document Server

    Domingues, Maria de Fátima F

    2017-01-01

    This brief provides a review of the evolution of optical fiber sensing solutions and related applications. Unique production methods are presented and discussed, highlighting their evolution and analyzing their complexity. Under this scope, this brief presents the existing silica optical fiber sensors and polymer optical fiber sensors solutions, comparing its field of action (sensitivity, accuracy), complexity of manufacture and economic cost. Special attention is given to low-cost production methods. This brief evaluates the different existing techniques, assessing the accuracy and suitability of these sensors for possible Internet of Things (IoT) integration in different considered scenarios. Critical analytical techniques, also covered in this brief, are expected to play a key role in the world of IoT and the smart city of tomorrow.

  1. Continuous Fuel Level Sensor Based on Spiral Side-Emitting Optical Fiber

    Directory of Open Access Journals (Sweden)

    Chengrui Zhao

    2012-01-01

    Full Text Available A continuous fuel level sensor using a side-emitting optical fiber is introduced in this paper. This sensor operates on the modulation of the light intensity in fiber, which is caused by the cladding’s acceptance angle change when it is immersed in fuel. The fiber is bent as a spiral shape to increase the sensor’s sensitivity by increasing the attenuation coefficient and fiber’s submerged length compared to liquid level. The attenuation coefficients of fiber with different bent radiuses in the air and water are acquired through experiments. The fiber is designed as a spiral shape with a steadily changing slope, and its response to water level is simulated. The experimental results taken in water and aviation kerosene demonstrate a performance of 0.9 m range and 10 mm resolution.

  2. Towards biochips using microstructured optical fiber sensors

    DEFF Research Database (Denmark)

    Rindorf, Lars Henning; Hoiby, Poul Erik; Jensen, Jesper Bo

    2006-01-01

    In this paper we present the first incorporation of a microstructured optical fiber (MOF) into biochip applications. A 16-mm-long piece of MOF is incorporated into an optic-fluidic coupler chip, which is fabricated in PMMA polymer using a CO2 laser. The developed chip configuration allows...... the continuous control of liquid flow through the MOF and simultaneous optical characterization. While integrated in the chip, the MOF is functionalized towards the capture of a specific single-stranded DNA string by immobilizing a sensing layer on the microstructured internal surfaces of the fiber. The sensing...... layer contains the DNA string complementary to the target DNA sequence and thus operates through the highly selective DNA hybridization process. Optical detection of the captured DNA was carried out using the evanescent-wave-sensing principle. Owing to the small size of the chip, the presented technique...

  3. Optic fiber pulse-diagnosis sensor of traditional Chinese medicine

    Science.gov (United States)

    Ni, J. S.; Jin, W.; Zhao, B. N.; Zhang, X. L.; Wang, C.; Li, S. J.; Zhang, F. X.; Peng, G. D.

    2013-09-01

    The wrist-pulse is a kind of signals, from which a lot of physiological and pathological status of patients are deduced according to traditional Chinese medicine theories. This paper designs a new optic fiber wrist-pulse sensor that based on a group of FBGs. Sensitivity of the optic fiber wrist-pulse measurement system reaches 0.05% FS and the range reaches 50kPa. Frequency response is from 0 Hz to 5 kHz. A group of typical pulse signal is given out in the paper to compare different status of patient. It will improve quantification of pulse diagnosis greatly.

  4. Laser of optical fiber composed by two coupled cavities: application as optical fiber sensor

    International Nuclear Information System (INIS)

    Vazquez S, R.A.; Kuzin, E.A.; Ibarra E, B.; May A, M.; Shlyagin, M.; Marquez B, I.

    2004-01-01

    We show an optical fiber laser sensor which consist of two cavities coupled and three fiber Bragg gratings. We used one Bragg grating (called reference) and two Bragg gratings (called sensors), which have the lower reflection wavelength. The reference grating with the two sensors grating make two cavities: first one is the internal cavity which has 4230 m of length and the another one is the external cavity which has 4277 m of length. Measuring the laser beating frequency for a resonance cavity and moving the frequency peaks when the another cavity is put in resonance, we prove that the arrangement can be used as a two points sensor for determining the difference of temperature or stress between these two points. (Author)

  5. Optical fiber sensors embedded in flexible polymer foils

    Science.gov (United States)

    van Hoe, Bram; van Steenberge, Geert; Bosman, Erwin; Missinne, Jeroen; Geernaert, Thomas; Berghmans, Francis; Webb, David; van Daele, Peter

    2010-04-01

    In traditional electrical sensing applications, multiplexing and interconnecting the different sensing elements is a major challenge. Recently, many optical alternatives have been investigated including optical fiber sensors of which the sensing elements consist of fiber Bragg gratings. Different sensing points can be integrated in one optical fiber solving the interconnection problem and avoiding any electromagnetical interference (EMI). Many new sensing applications also require flexible or stretchable sensing foils which can be attached to or wrapped around irregularly shaped objects such as robot fingers and car bumpers or which can even be applied in biomedical applications where a sensor is fixed on a human body. The use of these optical sensors however always implies the use of a light-source, detectors and electronic circuitry to be coupled and integrated with these sensors. The coupling of these fibers with these light sources and detectors is a critical packaging problem and as it is well-known the costs for packaging, especially with optoelectronic components and fiber alignment issues are huge. The end goal of this embedded sensor is to create a flexible optical sensor integrated with (opto)electronic modules and control circuitry. To obtain this flexibility, one can embed the optical sensors and the driving optoelectronics in a stretchable polymer host material. In this article different embedding techniques for optical fiber sensors are described and characterized. Initial tests based on standard manufacturing processes such as molding and laser structuring are reported as well as a more advanced embedding technique based on soft lithography processing.

  6. Characterization of Scintillating X-ray Optical Fiber Sensors

    Science.gov (United States)

    Sporea, Dan; Mihai, Laura; Vâţă, Ion; McCarthy, Denis; O'Keeffe, Sinead; Lewis, Elfed

    2014-01-01

    The paper presents a set of tests carried out in order to evaluate the design characteristics and the operating performance of a set of six X-ray extrinsic optical fiber sensors. The extrinsic sensor we developed is intended to be used as a low energy X-ray detector for monitoring radiation levels in radiotherapy, industrial applications and for personnel dosimetry. The reproducibility of the manufacturing process and the characteristics of the sensors were assessed. The sensors dynamic range, linearity, sensitivity, and reproducibility are evaluated through radioluminescence measurements, X-ray fluorescence and X-ray imaging investigations. Their response to the operating conditions of the excitation source was estimated. The effect of the sensors design and implementation, on the collecting efficiency of the radioluminescence signal was measured. The study indicated that the sensors are efficient only in the first 5 mm of the tip, and that a reflective coating can improve their response. Additional tests were done to investigate the concentricity of the sensors tip against the core of the optical fiber guiding the optical signal. The influence of the active material concentration on the sensor response to X-ray was studied. The tests were carried out by measuring the radioluminescence signal with an optical fiber spectrometer and with a Multi-Pixel Photon Counter. PMID:24556676

  7. Sensitive Leptospira DNA detection using tapered optical fiber sensor.

    Science.gov (United States)

    Zainuddin, Nurul H; Chee, Hui Y; Ahmad, Muhammad Z; Mahdi, Mohd A; Abu Bakar, Muhammad H; Yaacob, Mohd H

    2018-03-23

    This paper presents the development of tapered optical fiber sensor to detect a specific Leptospira bacteria DNA. The bacteria causes Leptospirosis, a deadly disease but with common early flu-like symptoms. Optical single mode fiber (SMF) of 125 μm diameter is tapered to produce 12 μm waist diameter and 15 cm length. The novel DNA-based optical fiber sensor is functionalized by incubating the tapered region with sodium hydroxide (NaOH), (3-Aminopropyl) triethoxysilane and glutaraldehyde. Probe DNA is immobilized onto the tapered region and subsequently hybridized by its complementary DNA (cDNA). The transmission spectra of the DNA-based optical fiber sensor are measured in the 1500 to 1600 nm wavelength range. It is discovered that the shift of the wavelength in the SMF sensor is linearly proportional with the increase in the cDNA concentrations from 0.1 to 1.0 nM. The sensitivity of the sensor toward DNA is measured to be 1.2862 nm/nM and able to detect as low as 0.1 fM. The sensor indicates high specificity when only minimal shift is detected for non-cDNA testing. The developed sensor is able to distinguish between actual DNA of Leptospira serovars (Canicola and Copenhageni) against Clostridium difficile (control sample) at very low (femtomolar) target concentrations. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Optical Fiber Sensor Based on Localized Surface Plasmon Resonance Using Silver Nanoparticles Photodeposited on the Optical Fiber End

    Directory of Open Access Journals (Sweden)

    J. Gabriel Ortega-Mendoza

    2014-10-01

    Full Text Available This paper reports the implementation of an optical fiber sensor to measure the refractive index in aqueous media based on localized surface plasmon resonance (LSPR. We have used a novel technique known as photodeposition to immobilize silver nanoparticles on the optical fiber end. This technique has a simple instrumentation, involves laser light via an optical fiber and silver nanoparticles suspended in an aqueous medium. The optical sensor was assembled using a tungsten lamp as white light, a spectrometer, and an optical fiber with silver nanoparticles. The response of this sensor is such that the LSPR peak wavelength is linearly shifted to longer wavelengths as the refractive index is increased, showing a sensitivity of 67.6 nm/RIU. Experimental results are presented.

  9. Engineering the development of optical fiber sensors for adverse environments

    International Nuclear Information System (INIS)

    Hastings, M.C.

    1994-01-01

    During the last decade, many optical fiber sensors have been developed for particular applications in harsh environments with limited success. Off-the-shelf optical fiber sensors and measurement systems are not available, partly because they have not been engineered to meet tough environmental requirements necessary for applications outside the laboratory. Moreover, no generalized computer-aided tools exist to help advance their development, design, and use. Computer-aided design tools currently being developed are described in this paper. Structural finite element analyses have been coupled with optoelastic analyses of both all-fiber interferometers and serial microbend sensors for distributed measurement of various physical quantities. The combined analyses have been parameterized and implemented on personal computers and work stations for use as design/development tools that can be used to determine the performance of different sensor configurations in various environments. Potentially, these computer-aided tools could be used for failure diagnosis and redesign of existing optical fiber sensors. Performances predicted by the computer simulations are verified with experimental data and numerical analyses from the literature. The long-term goal is to develop user-friendly software packages for both sensor manufacturers and end users

  10. Transformer Temperature Measurment Using Optical Fiber Based Microbend Sensor

    Directory of Open Access Journals (Sweden)

    Deepika YADAV

    2007-10-01

    Full Text Available Breakdown of transformers proves to be very expensive and inconvenient because it takes a lot of time for their replacement. During breakdown the industry also incurs heavy losses because of stoppage in production line. A system for monitoring the temperature of transformers is required. Existing sensors cannot be used for monitoring the temperature of transformers because they are sensitive to electrical signals and can cause sparking which can trigger fire since there is oil in transformers cooling coils. Optical fibers are electrically inert so this system will prove to be ideal for this application. Results of investigations carried out by simulating a configuration of Optical Fiber Temperature Sensor for transformers based on microbending using Matlab as a simulation tool to evaluate the effectiveness of this sensor have been communicated through this manuscript. The results are in the form of graphs of intensity modulation vs. the temperature.

  11. Distributed optical fiber sensors for integrated monitoring of railway infrastructures

    Science.gov (United States)

    Minardo, Aldo; Coscetta, Agnese; Porcaro, Giuseppe; Giannetta, Daniele; Bernini, Romeo; Zeni, Luigi

    2014-05-01

    We propose the application of a distributed optical fiber sensor based on stimulated Brillouin scattering, as an integrated system for safety monitoring of railway infrastructures. The strain distribution was measured dynamically along a 60 meters length of rail track, as well as along a 3-m stone arch bridge. The results indicate that distributed sensing technology is able to provide useful information in railway traffic and safety monitoring.

  12. Flexible optical fiber sensor based on polyurethane

    DEFF Research Database (Denmark)

    Kaysir, Md Rejvi; Stefani, Alessio; Lwin, Richard

    Polyurethane (PU) based hollow core fibers are investigated as optical sensors. The flexibility of PU fibers makes it suitable for sensing mechanical perturbations. We fabricated a PU fiber using the fiber drawing method, characterized the fiber and experimentally demonstrated a simple way...... to measure deformation, in the form of applied pressure....

  13. Optical Fiber Sensors Based on Nanoparticle-Embedded Coatings

    Directory of Open Access Journals (Sweden)

    Aitor Urrutia

    2015-01-01

    Full Text Available The use of nanoparticles (NPs in scientific applications has attracted the attention of many researchers in the last few years. The use of NPs can help researchers to tune the physical characteristics of the sensing coating (thickness, roughness, specific area, refractive index, etc. leading to enhanced sensors with response time or sensitivity better than traditional sensing coatings. Additionally, NPs also offer other special properties that depend on their nanometric size, and this is also a source of new sensing applications. This review focuses on the current status of research in the use of NPs within coatings in optical fiber sensing. Most used sensing principles in fiber optics are briefly described and classified into several groups: absorbance-based sensors, interferometric sensors, fluorescence-based sensors, fiber grating sensors, and resonance-based sensors, among others. For each sensor group, specific examples of the utilization of NP-embedded coatings in their sensing structure are reported.

  14. Radiation distribution sensor with optical fibers for high radiation fields

    International Nuclear Information System (INIS)

    Takada, Eiji; Kimura, Atsushi; Hosono, Yoneichi; Takahashi, Hiroyuki; Nakazawa, Masaharu

    1999-01-01

    Radiation distribution sensors with their feasibilities have been described in earlier works. However, due to large radiation induced transmission losses in optical fibers, especially in the visible wavelength region, it has been difficult to apply these techniques to high radiation fields. In this study, we proposed a new concept of optical fiber based radiation distribution measurements with near infrared (IR) emission. Near IR scintillators were attached to the ends of optical fibers, where the fibers were bundled and connected to an N-MOS line sensor or a cooled CCD camera. From the measurements of each area density, the radiation levels at the positions of the scintillators can be known. The linearity between the gamma dose rate at each scintillator and the registered counts has been examined. For correcting the radiation induced loss effects, we applied the Optical Time Domain Reflectometry technique to measure the loss distribution and from the results, a possibility for correction of the loss effect has been demonstrated. The applicable dose rate range was evaluated to be from 0.1 to 10 3 Gy/h. This system can be a promising tool as a flexible dose rate distribution monitor in radiation facilities like nuclear plants and accelerator facilities. (author)

  15. Optical fiber sensor for low dose gamma irradiation monitoring

    Science.gov (United States)

    de Andrés, Ana I.; Esteban, Ã.`scar; Embid, Miguel

    2016-05-01

    An optical fiber gamma ray detector is presented in this work. It is based on a Terbium doped Gadolinium Oxysulfide (Gd2O2S:Tb) scintillating powder which cover a chemically etched polymer fiber tip. This etching improves the fluorescence gathering by the optical fiber. The final diameter has been selected to fulfill the trade-off between light gathering and mechanical strength. Powder has been encapsulated inside a microtube where the fiber tip is immersed. The sensor has been irradiated with different air Kerma doses up to 2 Gy/h with a 137Cs source, and the spectral distribution of the fluorescence intensity has been recorded in a commercial grade CCD spectrometer. The obtained signal-to-noise ratio is good enough even for low doses, which has allowed to reduce the integration time in the spectrometer. The presented results show the feasibility for using low cost equipment to detect/measure ionizing radiation as gamma rays are.

  16. OPTICAL FIBER SENSOR TECHNOLOGIES FOR EFFICIENT AND ECONOMICAL OIL RECOVERY

    Energy Technology Data Exchange (ETDEWEB)

    Anbo Wang; Kristie L. Cooper; Gary R. Pickrell

    2003-06-01

    Efficient recovery of petroleum reserves from existing oil wells has been proven to be difficult due to the lack of robust instrumentation that can accurately and reliably monitor processes in the downhole environment. Commercially available sensors for measurement of pressure, temperature, and fluid flow exhibit shortened lifetimes in the harsh downhole conditions, which are characterized by high pressures (up to 20 kpsi), temperatures up to 250 C, and exposure to chemically reactive fluids. Development of robust sensors that deliver continuous, real-time data on reservoir performance and petroleum flow pathways will facilitate application of advanced recovery technologies, including horizontal and multilateral wells. This is the final report for the four-year program ''Optical Fiber Sensor Technologies for Efficient and Economical Oil Recovery'', funded by the National Petroleum Technology Office of the U.S. Department of Energy, and performed by the Center for Photonics Technology of the Bradley Department of Electrical and Computer Engineering at Virginia Tech from October 1, 1999 to March 31, 2003. The main objective of this research program was to develop cost-effective, reliable optical fiber sensor instrumentation for real-time monitoring of various key parameters crucial to efficient and economical oil production. During the program, optical fiber sensors were demonstrated for the measurement of temperature, pressure, flow, and acoustic waves, including three successful field tests in the Chevron/Texaco oil fields in Coalinga, California, and at the world-class oil flow simulation facilities in Tulsa, Oklahoma. Research efforts included the design and fabrication of sensor probes, development of signal processing algorithms, construction of test systems, development and testing of strategies for the protection of optical fibers and sensors in the downhole environment, development of remote monitoring capabilities allowing real

  17. Noncontact measurement of high temperature using optical fiber sensors

    Science.gov (United States)

    Claus, R. O.

    1990-01-01

    The primary goal of this research program was the investigation and application of noncontact temperature measurement techniques using optical techniques and optical fiber methods. In particular, a pyrometer utilizing an infrared optical light pipe and a multiwavelength filtering approach was designed, revised, and tested. This work was motivated by the need to measure the temperatures of small metallic pellets (approximately 3 mm diameter) in free fall at the Microgravity Materials Processing Drop Tube at NASA Marshall Space Flight Center. In addition, research under this program investigated the adaptation of holography technology to optical fiber sensors, and also examined the use of rare-earth dopants in optical fibers for use in measuring temperature. The pyrometer development effort involved both theoretical analysis and experimental tests. For the analysis, a mathematical model based on radiative transfer principles was derived. Key parameter values representative of the drop tube system, such as particle size, tube diameter and length, and particle temperature, were used to determine an estimate of the radiant flux that will be incident on the face of an optical fiber or light pipe used to collect radiation from the incandescent falling particle. An extension of this work examined the advantage of inclining or tilting the collecting fiber to increase the time that the falling particle remains in the fiber field-of-view. Those results indicate that increases in total power collected of about 15 percent may be realized by tilting the fiber. In order to determine the suitability of alternative light pipes and optical fibers, and experimental set-up for measuring the transmittance and insertion loss of infrared fibers considered for use in the pyrometer was assembled. A zirconium fluoride optical fiber and several bundles of hollow core fiber of varying diameters were tested. A prototype two-color pyrometer was assembled and tested at Virginia Tech, and then

  18. Recent Developments Of Optical Fiber Sensors For Automotive Use

    Science.gov (United States)

    Sasayama, Takao; Oho, Shigeru; Kuroiwa, Hiroshi; Suzuki, Seikoo

    1987-12-01

    Optical fiber sensing technologies are expected to apply for many future electronic control systems in automobiles, because of their original outstanding features, such as high noise immunity, high heat resistance, and flexible light propagation paths which can be applicable to measure the movements and directions of the mobiles. In this paper, two typical applications of fiber sensing technologies in automobiles have been described in detail. The combustion flame detector is one of the typical applications of a fiber spectroscopic technology which utilizes the feature of high noise and heat resistibility and remote sensibility. Measurements of engine combustion conditions, such as the detonation, the combustion initiation, and the air-fuel ratio, have been demonstrated in an experimental fiber sensing method. Fiber interferometers, such as a fiber gyroscope, have a lot of possibilities in future mobile applications because they are expandable to many kinds of measurements for movements and physical variables. An optical fiber gyroscope utilizing the single polarized optical fiber and optical devices has been developed. Quite an accurate measurement of vehicle position was displayed on a prototype navigation system which installed the fiber gyroscope as a rotational speed sensor.

  19. Fabrication and evaluation of hybrid silica/polymer optical fiber sensors for large strain measurement

    Science.gov (United States)

    Huang, Haiying

    2007-04-01

    Silica-based optical fiber sensors are widely used in structural health monitoring systems for strain and deflection measurement. One drawback of silica-based optical fiber sensors is their low strain toughness. In general, silica-based optical fiber sensors can only reliably measure strains up to 2%. Recently, polymer optical fiber sensors have been employed to measure large strain and deflection. Due to their high optical losses, the length of the polymer optical fibers is limited to 100 meters. In this paper, we present a novel economical technique to fabricate hybrid silica/polymer optical fiber strain sensors for large strain measurement. First, stress analysis of a surface-mounted optical fiber sensor is performed to understand the load distribution between the host structure and the optical fiber in relation to their mechanical properties. Next, the procedure of fabricating a polymer sensing element between two optical fibers is explained. The experimental set-up and the components used in the fabrication process are described in details. Mechanical testing results of the fabricated silica/polymer optical fiber strain sensor are presented.

  20. Fluoride contamination sensor based on optical fiber grating technology

    Science.gov (United States)

    Jadhav, Mangesh S.; Laxmeshwar, Lata S.; Akki, Jyoti F.; Raikar, P. U.; Kumar, Jitendra; Prakash, Om; Raikar, U. S.

    2017-11-01

    A number of distinct advantages of the optical fiber technology in the field of sensors and communications which leads to enormous applications. Fiber Bragg grating (FBG) developed from the fabrication of photosensitive fiber through phase mask technique is used in the present report. The designed fiber sensor used for the detection and determination of contaminants in drinking water at ppm & ppb level and it is considered as a special type of concentration sensor. The test samples of drinking water have been collected from different regions. In this paper we have calibrated the FBG sensor to detect Flouride concentration in drinking water in the range of 0.05-8 ppm. According to WHO, the normal range of fluoride content in drinking water is about 0.7 ppm to 1.5 ppm. The results for resultant spectral shifts for test samples are closely agree with standard values.

  1. Optical Fiber Sensor Technologies for Efficient and Economical Oil Recovery

    Energy Technology Data Exchange (ETDEWEB)

    Wang, a.; Pickrell, G.; Xiao, H.; May, r.

    2003-02-27

    The overall goal of this project was to develop reliable cost effective sensors for application in the down-hole environment. The physical parameters measured by these sensors were temperature, pressure, flow and acoustic signals. Sensor head configurations for each of the physical measurands were optimized to increase the sensitivity to the particular measurand of interest while decreasing the cross-sensitivity to the other physical measurands and to environmental influences. In addition, the optical signal demodulation electronics was designed to be insensitive to environmental influences while maintaining the required resolution, precision and accuracy of the parameter being sensed. The influence of potentially detrimental agents such as water in the down-hole environment was investigated as well as methods to protect both the optical fiber and the sensor from these detrimental effects.

  2. Polymer optical fiber sensors in human life safety

    Science.gov (United States)

    Marques, C. A. F.; Webb, D. J.; Andre, P.

    2017-07-01

    The current state of research into polymer optical fiber (POF) sensors linked to safety in human life is summarized in this paper. This topic is directly related with new solutions for civil aircraft, structural health monitoring, healthcare and biomedicine fields. In the last years, the properties of polymers have been explored to identify situations offering potential advantages over conventional silica fiber sensing technology, replacing, in some cases, problematic electronic technology used in these mentioned fields, where there are some issues to overcome. POFs could preferably replace their silica counterparts, with improved performance and biocompatibility. Finally, new developments are reported which use the unique properties of POF.

  3. An optical fiber expendable seawater temperature/depth profile sensor

    Science.gov (United States)

    Zhao, Qiang; Chen, Shizhe; Zhang, Keke; Yan, Xingkui; Yang, Xianglong; Bai, Xuejiao; Liu, Shixuan

    2017-10-01

    Marine expendable temperature/depth profiler (XBT) is a disposable measuring instrument which can obtain temperature/depth profile data quickly in large area waters and mainly used for marine surveys, scientific research, military application. The temperature measuring device is a thermistor in the conventional XBT probe (CXBT)and the depth data is only a calculated value by speed and time depth calculation formula which is not an accurate measurement result. Firstly, an optical fiber expendable temperature/depth sensor based on the FBG-LPG cascaded structure is proposed to solve the problems of the CXBT, namely the use of LPG and FBG were used to detect the water temperature and depth, respectively. Secondly, the fiber end reflective mirror is used to simplify optical cascade structure and optimize the system performance. Finally, the optical path is designed and optimized using the reflective optical fiber end mirror. The experimental results show that the sensitivity of temperature and depth sensing based on FBG-LPG cascade structure is about 0.0030C and 0.1%F.S. respectively, which can meet the requirements of the sea water temperature/depth observation. The reflectivity of reflection mirror is in the range from 48.8% to 72.5%, the resonant peak of FBG and LPG are reasonable and the whole spectrum are suitable for demodulation. Through research on the optical fiber XBT (FXBT), the direct measurement of deep-sea temperature/depth profile data can be obtained simultaneously, quickly and accurately. The FXBT is a new all-optical seawater temperature/depth sensor, which has important academic value and broad application prospect and is expected to replace the CXBT in the future.

  4. Optical Fiber High Temperature Sensor Instrumentation for Energy Intensive Industries

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, Kristie L.; Wang, Anbo; Pickrell, Gary R.

    2006-11-14

    This report summarizes technical progress during the program “Optical Fiber High Temperature Sensor Instrumentation for Energy Intensive Industries”, performed by the Center for Photonics Technology of the Bradley Department of Electrical and Computer Engineering at Virginia Tech. The objective of this program was to use technology recently invented at Virginia Tech to develop and demonstrate the application of self-calibrating optical fiber temperature and pressure sensors to several key energy-intensive industries where conventional, commercially available sensors exhibit greatly abbreviated lifetimes due primarily to environmental degradation. A number of significant technologies were developed under this program, including • a laser bonded silica high temperature fiber sensor with a high temperature capability up to 700°C and a frequency response up to 150 kHz, • the world’s smallest fiber Fabry-Perot high temperature pressure sensor (125 x 20 μm) with 700°C capability, • UV-induced intrinsic Fabry-Perot interferometric sensors for distributed measurement, • a single crystal sapphire fiber-based sensor with a temperature capability up to 1600°C. These technologies have been well demonstrated and laboratory tested. Our work plan included conducting major field tests of these technologies at EPRI, Corning, Pratt & Whitney, and Global Energy; field validation of the technology is critical to ensuring its usefulness to U.S. industries. Unfortunately, due to budget cuts, DOE was unable to follow through with its funding commitment to support Energy Efficiency Science Initiative projects and this final phase was eliminated.

  5. Control systems using modal domain optical fiber sensors for smart structure applications

    Science.gov (United States)

    Lindner, Douglas K.; Reichard, Karl M.

    1991-01-01

    Recently, a new class of sensors has emerged for structural control which respond to environmental changes over a significant gauge length; these sensors are called distributed-effect sensors. These sensors can be fabricated with spatially varying sensitivity to the distributed measurand, and can be configured to measure a variety of structural parameters which can not be measured directly using point sensors. Examples of distributed-effect sensors include piezoelectric film, holographic sensors, and modal domain optical fiber sensors. Optical fiber sensors are particularly attractive for smart structure applications because they are flexible, have low mass, and can easily be embedded directly into materials. In this paper we describe the implementation of weighted modal domain optical fiber sensors. The mathematical model of the modal domain optical fiber sensor model is described and used to derive an expression for the sensor sensitivity. The effects of parameter variations on the sensor sensitivity are demonstrated to illustrate methods of spatially varying the sensor sensitivity.

  6. Optical Fiber Sensors Based on Polymeric Sensitive Coatings

    Directory of Open Access Journals (Sweden)

    Pedro J. Rivero

    2018-03-01

    Full Text Available Polymer technology is one of the fastest growing fields of contemporary research due to the possibility of using a wide variety of synthetic chemical routes for obtaining a polymeric network with a well-defined structure, resulting in materials with outstanding macroscopic properties. Surface engineering techniques based on the implementation of polymeric structures can be used as an interesting tool for the design of materials with functional properties. In this sense, the use of fabrication techniques for the design of nanostructured polymeric coatings is showing an important growth due to the intrinsic advantages of controlling the structure at a nanoscale level because physical, chemical, or optical properties can be considerably improved in comparison with the bulk materials. In addition, the presence of these sensitive polymeric coatings on optical fiber is a hot topic in the scientific community for its implementation in different market niches because a wide variety of parameters can be perfectly measured with a high selectivity, sensitivity, and fast response time. In this work, the two main roles that a polymeric sensitive matrix can play on an optical fiber for sensing applications are evaluated. In a first section, the polymers are used as a solid support for the immobilization of specific sensitive element, whereas in the second section the polymeric matrix is used as the chemical transducer itself. Additionally, potential applications of the optical fiber sensors in fields as diverse as biology, chemistry, engineering, environmental, industry or medicine will be presented in concordance with these two main roles of the polymeric sensitive matrices.

  7. Development of an optical fiber sensor for angular displacement measurements.

    Science.gov (United States)

    Jung, Gu-In; Kim, Ji-Sun; Lee, Tae-Hee; Choi, Ju-Hyeon; Oh, Han-Byeol; Kim, A-Hee; Eom, Gwang-Moon; Lee, Jeong-Hwan; Chung, Soon-Cheol; Park, Jong-Rak; Lee, Young-Jae; Park, Hee-Jung; Jun, Jae-Hoon

    2014-01-01

    For diagnostic and therapeutic purposes, the joint angle measurement of a patient after an accident or a surgical operation is significant for monitoring and evaluating the recovering process. This paper proposed an optical fiber sensor for the measurement of angular displacement. The effect of beveled fiber angle on the detected light signal was investigated to find an appropriate mathematical model. Beveled fiber tips redirected the light over a range of angles away from the fiber axis. Inverse polynomial models were applied to directly obtain and display the joint angle change in real time with the Lab-VIEW program. The actual joint angle correlated well with the calculated LabVIEW output angle over the test range. The proposed optical sensor is simple, cost effective, small in size, and can evaluate the joint angle in real time. This method is expected to be useful in the field of rehabilitation and sport science.

  8. Damage and failure detection of composites using optical fiber vibration sensor

    International Nuclear Information System (INIS)

    Yang, Y. C.; Han, K. S.

    2001-01-01

    An intensity-based optical fiber vibration sensor is applied to detect and evaluate damages and fiber failure of composites. The optical fiber vibration sensor is constructed by placing two cleaved fiber end, one of which is cantilevered in a hollow glass tube. The movement of the cantilevered section lags behind the rest of the sensor in response to an applied vibration and the amount of light coupled between the two fibers is thereby modulated. Vibration characteristics of the optical fiber vibration sensor are investigated. Surface mounted optical fiber vibration sensor is used in tensile and indentation test. Experimental results show that the optical fiber sensor can detect damages and fiber failure of composites correctly

  9. A Polymer Optical Fiber Temperature Sensor Based on Material Features.

    Science.gov (United States)

    Leal-Junior, Arnaldo; Frizera-Netoc, Anselmo; Marques, Carlos; Pontes, Maria José

    2018-01-19

    This paper presents a polymer optical fiber (POF)-based temperature sensor. The operation principle of the sensor is the variation in the POF mechanical properties with the temperature variation. Such mechanical property variation leads to a variation in the POF output power when a constant stress is applied to the fiber due to the stress-optical effect. The fiber mechanical properties are characterized through a dynamic mechanical analysis, and the output power variation with different temperatures is measured. The stress is applied to the fiber by means of a 180° curvature, and supports are positioned on the fiber to inhibit the variation in its curvature with the temperature variation. Results show that the sensor proposed has a sensitivity of 1.04 × 10 -3 °C -1 , a linearity of 0.994, and a root mean squared error of 1.48 °C, which indicates a relative error of below 2%, which is lower than the ones obtained for intensity-variation-based temperature sensors. Furthermore, the sensor is able to operate at temperatures up to 110 °C, which is higher than the ones obtained for similar POF sensors in the literature.

  10. Reconfigurable optical interconnection network for multimode optical fiber sensor arrays

    Science.gov (United States)

    Chen, R. T.; Robinson, D.; Lu, H.; Wang, M. R.; Jannson, T.; Baumbick, R.

    1992-01-01

    A single-source, single-detector architecture has been developed to implement a reconfigurable optical interconnection network multimode optical fiber sensor arrays. The network was realized by integrating LiNbO3 electrooptic (EO) gratings working at the Raman Na regime and a massive fan-out waveguide hologram (WH) working at the Bragg regime onto a multimode glass waveguide. The glass waveguide utilized the whole substrate as a guiding medium. A 1-to-59 massive waveguide fan-out was demonstrated using a WH operating at 514 nm. Measured diffraction efficiency of 59 percent was experimentally confirmed. Reconfigurability of the interconnection was carried out by generating an EO grating through an externally applied electric field. Unlike conventional single-mode integrated optical devices, the guided mode demonstrated has an azimuthal symmetry in mode profile which is the same as that of a fiber mode.

  11. Optical-fiber strain sensors with asymmetric etched structures.

    Science.gov (United States)

    Vaziri, M; Chen, C L

    1993-11-01

    Optical-fiber strain gauges with asymmetric etched structures have been analyzed, fabricated, and tested. These sensors are very sensitive with a gauge factor as high as 170 and a flat frequency response to at least 2.7 kHz. The gauge factor depends on the asymmetry of the etched structures and the number of etched sections. To understand the physical principles involved, researchers have used structural analysis programs based on a finite-element method to analyze fibers with asymmetric etched structures under tensile stress. The results show that lateral bends are induced on the etched fibers when they are stretched axially. To relate the lateral bending to the optical attenuation, we have also employed a ray-tracing technique to investigate the dependence of the attenuation on the structural deformation. Based on the structural analysis and the ray-tracing study parameters affecting the sensitivity have been studied. These results agree with the results of experimental investigations.

  12. Vibration sensing in flexible structures using a distributed-effect modal domain optical fiber sensor

    Science.gov (United States)

    Reichard, Karl M.; Lindner, Douglas K.; Claus, Richard O.

    1991-01-01

    Modal domain optical fiber sensors have recently been employed in the implementation of system identification algorithms and the closed-loop control of vibrations in flexible structures. The mathematical model of the modal domain optical fiber sensor used in these applications, however, only accounted for the effects of strain in the direction of the fiber's longitudinal axis. In this paper, we extend this model to include the effects of arbitrary stress. Using this sensor model, we characterize the sensor's sensitivity and dynamic range.

  13. Optical fiber strain sensor using fiber resonator based on frequency comb Vernier spectroscopy

    DEFF Research Database (Denmark)

    Zhang, Liang; Lu, Ping; Chen, Li

    2012-01-01

    A novel (to our best knowledge) optical fiber strain sensor using a fiber ring resonator based on frequency comb Vernier spectroscopy is proposed and demonstrated. A passively mode-locked optical fiber laser is employed to generate a phased-locked frequency comb. Strain applied to the optical fib...

  14. Characteristic Analysis Light Intensity Sensor Based On Plastic Optical Fiber At Various Configuration

    Science.gov (United States)

    Arifin, A.; Lusiana; Yunus, Muhammad; Dewang, Syamsir

    2018-03-01

    This research discusses the light intensity sensor based on plastic optical fiber. This light intensity sensor is made of plastic optical fiber consisting of two types, namely which is cladding and without cladding. Plastic optical fiber used multi-mode step-index type made of polymethyl metacrylate (PMMA). The infrared LED emits light into the optical fiber of the plastic and is subsequently received by the phototransistor to be converted to an electric voltage. The sensor configuration is made with three models: straight configuration, U configuration and gamma configuration with cladding and without cladding. The measured light source uses a 30 Watt high power LED with a light intensity of 0 to 10 Klux. The measured light intensity will affect the propagation of light inside the optical fiber sensor. The greater the intensity of the measured light, the greater the output voltage that is read on the computer. The results showed that the best optical fiber sensor characteristics were obtained in U configuration. Sensors with U-configuration without cladding had the best sensitivity and resolution values of 0.0307 volts/Klux and 0.0326 Klux. The advantages of this measuring light intensity based on the plastic optical fiber instrument are simple, easy-to-make operational systems, low cost, high sensitivity and resolution.

  15. Residual strain sensor using Al-packaged optical fiber and Brillouin optical correlation domain analysis.

    Science.gov (United States)

    Choi, Bo-Hun; Kwon, Il-Bum

    2015-03-09

    We propose a distributed residual strain sensor that uses an Al-packaged optical fiber for the first time. The residual strain which causes Brillouin frequency shifts in the optical fiber was measured using Brillouin optical correlation domain analysis with 2 cm spatial resolution. We quantified the Brillouin frequency shifts in the Al-packaged optical fiber by the tensile stress and compared them for a varying number of Al layers in the optical fiber. The Brillouin frequency shift of an optical fiber with one Al layer had a slope of 0.038 MHz/με with respect to tensile stress, which corresponds to 78% of that for an optical fiber without Al layers. After removal of the stress, 87% of the strain remained as residual strain. When different tensile stresses were randomly applied, the strain caused by the highest stress was the only one detected as residual strain. The residual strain was repeatedly measured for a time span of nine months for the purpose of reliability testing, and there was no change in the strain except for a 4% reduction, which is within the error tolerance of the experiment. A composite material plate equipped with our proposed Al-packaged optical fiber sensor was hammered for impact experiment and the residual strain in the plate was successfully detected. We suggest that the Al-packaged optical fiber can be adapted as a distributed strain sensor for smart structures, including aerospace structures.

  16. Single-Crystal Sapphire Optical Fiber Sensor Instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Pickrell, Gary [Virginia Polytechnic Inst. & State Univ., Blacksburg, VA (United States); Scott, Brian [Virginia Polytechnic Inst. & State Univ., Blacksburg, VA (United States); Wang, Anbo [Virginia Polytechnic Inst. & State Univ., Blacksburg, VA (United States); Yu, Zhihao [Virginia Polytechnic Inst. & State Univ., Blacksburg, VA (United States)

    2013-12-31

    This report summarizes technical progress on the program “Single-Crystal Sapphire Optical Fiber Sensor Instrumentation,” funded by the National Energy Technology Laboratory of the U.S. Department of Energy, and performed by the Center for Photonics Technology of the Bradley Department of Electrical and Computer Engineering at Virginia Tech. This project was completed in three phases, each with a separate focus. Phase I of the program, from October 1999 to April 2002, was devoted to development of sensing schema for use in high temperature, harsh environments. Different sensing designs were proposed and tested in the laboratory. Phase II of the program, from April 2002 to April 2009, focused on bringing the sensor technologies, which had already been successfully demonstrated in the laboratory, to a level where the sensors could be deployed in harsh industrial environments and eventually become commercially viable through a series of field tests. Also, a new sensing scheme was developed and tested with numerous advantages over all previous ones in Phase II. Phase III of the program, September 2009 to December 2013, focused on development of the new sensing scheme for field testing in conjunction with materials engineering of the improved sensor packaging lifetimes. In Phase I, three different sensing principles were studied: sapphire air-gap extrinsic Fabry-Perot sensors; intensity-based polarimetric sensors; and broadband polarimetric sensors. Black body radiation tests and corrosion tests were also performed in this phase. The outcome of the first phase of this program was the selection of broadband polarimetric differential interferometry (BPDI) for further prototype instrumentation development. This approach is based on the measurement of the optical path difference (OPD) between two orthogonally polarized light beams in a single-crystal sapphire disk. At the beginning of Phase II, in June 2004, the BPDI sensor was tested at the Wabash River coal gasifier

  17. Interferometric microstructured polymer optical fiber ultrasound sensor for optoacoustic endoscopic imaging in biomedical applications

    DEFF Research Database (Denmark)

    Gallego, Daniel; Sáez-Rodríguez, David; Webb, David

    2014-01-01

    to conventional piezoelectric transducers. These kind of sensors, made of biocompatible polymers, are good candidates for the sensing element in an optoacoustic endoscope because of its high sensitivity, its shape and its non-brittle and non-electric nature. The acoustic sensitivity of the intrinsic fiber optic......We report a characterization of the acoustic sensitivity of microstructured polymer optical fiber interferometric sensors at ultrasonic frequencies from 100kHz to 10MHz. The use of wide-band ultrasonic fiber optic sensors in biomedical ultrasonic and optoacoustic applications is an open alternative...... interferometric sensors depends strongly of the material which is composed of. In this work we compare experimentally the intrinsic ultrasonic sensitivities of a PMMA mPOF with other three optical fibers: a singlemode silica optical fiber, a single-mode polymer optical fiber and a multimode graded...

  18. Optical Fiber Force Myography Sensor for Identification of Hand Postures

    Directory of Open Access Journals (Sweden)

    Eric Fujiwara

    2018-01-01

    Full Text Available A low-cost optical fiber force myography sensor for noninvasive hand posture identification is proposed. The transducers are comprised of 10 mm periodicity silica multimode fiber microbending devices mounted in PVC plates, providing 0.05 N−1 sensitivity over ~20 N range. Next, the transducers were attached to the user forearm by means of straps in order to monitor the posterior proximal radial, the anterior medial ulnar, and the posterior distal radial muscles, and the acquired FMG optical signals were correlated to the performed gestures using a 5 hidden layers, 20-neuron artificial neural network classifier with backpropagation architecture, followed by a competitive layer. The overall results for 9 postures and 6 subjects indicated a 98.4% sensitivity and 99.7% average accuracy, being comparable to the electromyographic approaches. Moreover, in contrast to the current setups, the proposed methodology allows the identification of poses characterized by different configurations of fingers and wrist joint displacements with the utilization of only 3 transducers and a simple interrogation scheme, being suitable to further applications in human-computer interfaces.

  19. Single Mode Optical Fiber based Refractive Index Sensor using Etched Cladding

    OpenAIRE

    Kumar, Ajay; Gupta, Geeta; Mallik, Arun; Bhatnagar, Anuj

    2011-01-01

    The use of optical fiber for sensor applications is a topic of current interest. We report the fabrication of etched single mode optical fiber based refractive index sensor. Experiments are performed to determine the etch rate of fiber in buffered hydrofluoric acid, which can be high or low depending upon the temperature at which etching is carried out. Controlled wet etching of fiber cladding is performed using these measurements and etched fiber region is tested for refractive index sensing...

  20. Aviation Fuel Gauging Sensor Utilizing Multiple Diaphragm Sensors Incorporating Polymer Optical Fiber Bragg Gratings

    DEFF Research Database (Denmark)

    Marques, C. A. F.; Pospori, A.; Saez-Rodriguez, D.

    2016-01-01

    A high-performance fuel gauging sensor is described that uses five diaphragm-based pressure sensors, which are monitored using a linear array of polymer optical fiber Bragg gratings. The sensors were initially characterized using water, revealing a sensitivity of 98 pm/cm for four of the sensors...... of sensors manufactured with a polyurethane-based diaphragm showed no measurable deterioration over a three month period immersed in fuel. These sensors exhibited a sensitivity of 39 pm/cm, which is less than the silicone rubber devices due to the stiffer nature of the polyurethane material used....

  1. Design and development of an optical fiber sensor for hydrogen detection

    International Nuclear Information System (INIS)

    Perrotton, Cedric

    2012-01-01

    Hydrogen detection is an environmental priority. Numerous hydrogen sensors have been developed, but none of them meet the industry requirements. Optical fiber sensors, electrically isolated, are excellent candidates for operating in explosive environments. Our goal is to develop an intrinsic optical fiber sensor based on Surface Plasmon Resonance. In this thesis, we study two optical fiber hydrogen sensors. The first sensor, based on amplitude modulation, consists of a thin Pd layer deposited on the multimode fiber core, after removing the optical cladding. The second design, based on wavelength modulation, consists of replacing the single Pd layer by a Au/SiO 2 /Pd multilayer stack. We demonstrate in this thesis that plasmonic sensors may be a solution to develop fast and reliable fiber hydrogen sensors. Finally, we study Mg alloys as hydrogen sensitive material in order to improve the detection range of hydrogen sensors. (author)

  2. Graphene Oxide in Lossy Mode Resonance-Based Optical Fiber Sensors for Ethanol Detection

    Directory of Open Access Journals (Sweden)

    Miguel Hernaez

    2017-12-01

    Full Text Available The influence of graphene oxide (GO over the features of an optical fiber ethanol sensor based on lossy mode resonances (LMR has been studied in this work. Four different sensors were built with this aim, each comprising a multimode optical fiber core fragment coated with a SnO2 thin film. Layer by layer (LbL coatings made of 1, 2 and 4 bilayers of polyethyleneimine (PEI and graphene oxide were deposited onto three of these devices and their behavior as aqueous ethanol sensors was characterized and compared with the sensor without GO. The sensors with GO showed much better performance with a maximum sensitivity enhancement of 176% with respect to the sensor without GO. To our knowledge, this is the first time that GO has been used to make an optical fiber sensor based on LMR.

  3. Graphene Oxide in Lossy Mode Resonance-Based Optical Fiber Sensors for Ethanol Detection.

    Science.gov (United States)

    Hernaez, Miguel; Mayes, Andrew G; Melendi-Espina, Sonia

    2017-12-27

    The influence of graphene oxide (GO) over the features of an optical fiber ethanol sensor based on lossy mode resonances (LMR) has been studied in this work. Four different sensors were built with this aim, each comprising a multimode optical fiber core fragment coated with a SnO₂ thin film. Layer by layer (LbL) coatings made of 1, 2 and 4 bilayers of polyethyleneimine (PEI) and graphene oxide were deposited onto three of these devices and their behavior as aqueous ethanol sensors was characterized and compared with the sensor without GO. The sensors with GO showed much better performance with a maximum sensitivity enhancement of 176% with respect to the sensor without GO. To our knowledge, this is the first time that GO has been used to make an optical fiber sensor based on LMR.

  4. Polymer Optical Fiber Compound Parabolic Concentrator fiber tip based glucose sensor: In-Vitro Testing

    DEFF Research Database (Denmark)

    Hassan, Hafeez Ul; Janting, Jakob; Aasmul, Soren

    2016-01-01

    We present in-vitro sensing of glucose using a newly developed efficient optical fiber glucose sensor based on a Compound Parabolic Concentrator (CPC) tipped polymer optical fiber (POF). A batch of 9 CPC tipped POF sensors with a 35 mm fiber length is shown to have an enhanced fluorescence pickup...... efficiency with an average increment factor of 1.7 as compared to standard POF sensors with a plane cut fiber tip. Invitro measurements for two glucose concentrations (40 and 400 mg/dL) confirm that the CPC tipped sensors efficiently can detect both glucose concentrations. it sets the footnote at the bottom...

  5. Optical fiber sensors FBG to the structural health monitoring of bridges

    International Nuclear Information System (INIS)

    Navarro-Henriquez, Francisco

    2014-01-01

    Systems with optical fiber sensors FBG (Fiber Bragg Grating) are consolidated in the Structural Health Monitoring (SHM) of bridges, static and dynamic nondestructive testing with measurements of deformation, displacement, deflection, temperature and vibrations. A brief introduction to the technology is presented and the fundamentals of optical fiber sensors, their use and comparative advantages over its traditional counterpart. The practice of the FBG sensor application is described. The characteristics of these sensors and measurement graphics are presented. Some key aspects to consider for proper use in the field are mentioned. (author) [es

  6. Miniature all-silica optical fiber pressure sensor with an ultrathin uniform diaphragm.

    Science.gov (United States)

    Wang, Wenhui; Wu, Nan; Tian, Ye; Niezrecki, Christopher; Wang, Xingwei

    2010-04-26

    This paper presents an all-silica miniature optical fiber pressure/acoustic sensor based on the Fabry-Perot (FP) interferometric principle. The endface of the etched optical fiber tip and silica thin diaphragm on it form the FP structure. The uniform and thin silica diaphragm was fabricated by etching away the silicon substrate from a commercial silicon wafer that has a thermal oxide layer. The thin film was directly thermally bonded to the endface of the optical fiber thus creating the Fabry-Perot cavity. Thin films with a thickness from 1microm to 3microm have been bonded successfully. The sensor shows good linearity and hysteresis during measurement. A sensor with 0.75 microm-thick diaphragm thinned by post silica etching was demonstrated to have a sensitivity of 11 nm/kPa. The new sensor has great potential to be used as a non-intrusive pressure sensor in a variety of sensing applications.

  7. Nonlinear fiber-optic strain sensor based on four-wave mixing in microstructured optical fiber

    DEFF Research Database (Denmark)

    Gu, Bobo; Yuan, Scott Wu; Frosz, Michael H.

    2012-01-01

    We demonstrate a nonlinear fiber-optic strain sensor, which uses the shifts of four-wave mixing Stokes and anti-Stokes peaks caused by the strain-induced changes in the structure and refractive index of a microstructured optical fiber. The sensor thus uses the inherent nonlinearity of the fiber a...

  8. Truly Distributed Optical Fiber Sensors for Structural Health Monitoring: From the Telecommunication Optical Fiber Drawling Tower to Water Leakage Detection in Dikes and Concrete Structure Strain Monitoring

    Directory of Open Access Journals (Sweden)

    Jean-Marie Henault

    2010-01-01

    Full Text Available Although optical fiber sensors have been developed for 30 years, there is a gap between lab experiments and field applications. This article focuses on specific methods developed to evaluate the whole sensing chain, with an emphasis on (i commercially-available optoelectronic instruments and (ii sensing cable. A number of additional considerations for a successful pairing of these two must be taken into account for successful field applications. These considerations are further developed within this article and illustrated with practical applications of water leakage detection in dikes and concrete structures monitoring, making use of distributed temperature and strain sensing based on Rayleigh, Raman, and Brillouin scattering in optical fibers. They include an adequate choice of working wavelengths, dedicated localization processes, choices of connector type, and further include a useful selection of traditional reference sensors to be installed nearby the optical fiber sensors, as well as temperature compensation in case of strain sensing.

  9. Surface-Enhanced Raman Scattering Sensor on an Optical Fiber Probe Fabricated with a Femtosecond Laser

    OpenAIRE

    Ma, Xiaodong; Huo, Haibin; Wang, Wenhui; Tian, Ye; Wu, Nan; Guthy, Charles; Shen, Mengyan; Wang, Xingwei

    2010-01-01

    A novel fabrication method for surface-enhanced Raman scattering (SERS) sensors that used a fast femtosecond (fs) laser scanning process to etch uniform patterns and structures on the endface of a fused silica optical fiber, which is then coated with a thin layer of silver through thermal evaporation is presented. A high quality SERS signal was detected on the patterned surface using a Rhodamine 6G (Rh6G) solution. The uniform SERS sensor built on the tip of the optical fiber tip was small, l...

  10. Functionality enhancement of industrialized optical fiber sensors and system developed for full-scale pavement monitoring.

    Science.gov (United States)

    Wang, Huaping; Liu, Wanqiu; He, Jianping; Xing, Xiaoying; Cao, Dandan; Gao, Xipeng; Hao, Xiaowei; Cheng, Hongwei; Zhou, Zhi

    2014-05-19

    Pavements always play a predominant role in transportation. Health monitoring of pavements is becoming more and more significant, as frequently suffering from cracks, rutting, and slippage renders them prematurely out of service. Effective and reliable sensing elements are thus in high demand to make prognosis on the mechanical properties and occurrence of damage to pavements. Therefore, in this paper, various types of functionality enhancement of industrialized optical fiber sensors for pavement monitoring are developed, with the corresponding operational principles clarified in theory and the performance double checked by basic experiments. Furthermore, a self-healing optical fiber sensing network system is adopted to accomplish full-scale monitoring of pavements. The application of optical fiber sensors assembly and self-healing network system in pavement has been carried out to validate the feasibility. It has been proved that the research in this article provides a valuable method and meaningful guidance for the integrity monitoring of civil structures, especially pavements.

  11. Functionality Enhancement of Industrialized Optical Fiber Sensors and System Developed for Full-Scale Pavement Monitoring

    Directory of Open Access Journals (Sweden)

    Huaping Wang

    2014-05-01

    Full Text Available Pavements always play a predominant role in transportation. Health monitoring of pavements is becoming more and more significant, as frequently suffering from cracks, rutting, and slippage renders them prematurely out of service. Effective and reliable sensing elements are thus in high demand to make prognosis on the mechanical properties and occurrence of damage to pavements. Therefore, in this paper, various types of functionality enhancement of industrialized optical fiber sensors for pavement monitoring are developed, with the corresponding operational principles clarified in theory and the performance double checked by basic experiments. Furthermore, a self-healing optical fiber sensing network system is adopted to accomplish full-scale monitoring of pavements. The application of optical fiber sensors assembly and self-healing network system in pavement has been carried out to validate the feasibility. It has been proved that the research in this article provides a valuable method and meaningful guidance for the integrity monitoring of civil structures, especially pavements.

  12. Polymer Optical Fiber Sensor and the Prediction of Sensor Response Utilizing Artificial Neural Networks

    Science.gov (United States)

    Haroglu, Derya

    The global market researches showed that there is a growing trend in the field of polymer optical fiber (POF) and POF sensors. Telecommunications, medicine, defense, aerospace, and automotive are the application areas of fiber optic sensors, where the automotive industry is the most promising application area for innovations in the field of POF sensors. The POF sensors in automobiles are particularly for detection of seat occupancy, and intelligent pedestrian protection systems. This dissertation investigates graded index perfluorinated polymer optical fiber as an intensity modulated intrinsic sensor for application in automotive seat occupancy sensing. Since a fiber optic sensor has a high bandwidth, is small in size, is lightweight, and is immune to electromagnetic interference (EMI) it offers higher performance than that of its electrical based counterparts such as strain gauge, elastomeric bladder, and resistive sensor systems. This makes the fiber optic sensor a potential suitable material for seat occupancy sensing. A textile-based fiber optic sensor was designed to be located in the area beneath the typical seated human's thighs. The pressure interval under which the proposed POF sensor design could perform well was found to be between 0.18 and 0.21 N/cm2, where perfluorinated (PF) graded index (GI) POF (62.5/750 mum) was used as the POF material. In addition, the effect of the automotive seat covering including face material (fabric) and foam backing to the sensor's performance was analyzed. The face fabric structure and the thickness of foam backing were not found to be significant factors to change the sensor results. A research study, survey, was conducted of which purpose was to better understand market demands in terms of sensor performance characteristics for automotive seat weight sensors, as a part of the Quality Function Deployment (QFD) House of Quality analysis. The companies joined the survey agreed on the first 5 most important sensor

  13. Priority design parameters of industrialized optical fiber sensors in civil engineering

    Science.gov (United States)

    Wang, Huaping; Jiang, Lizhong; Xiang, Ping

    2018-03-01

    Considering the mechanical effects and the different paths for transferring deformation, optical fiber sensors commonly used in civil engineering have been systematically classified. Based on the strain transfer theory, the relationship between the strain transfer coefficient and allowable testing error is established. The proposed relationship is regarded as the optimal control equation to obtain the optimal value of sensors that satisfy the requirement of measurement precision. Furthermore, specific optimization design methods and priority design parameters of the classified sensors are presented. This research indicates that (1) strain transfer theory-based optimization design method is much suitable for the sensor that depends on the interfacial shear stress to transfer the deformation; (2) the priority design parameters are bonded (sensing) length, interfacial bonded strength, elastic modulus and radius of protective layer and thickness of adhesive layer; (3) the optimization design of sensors with two anchor pieces at two ends is independent of strain transfer theory as the strain transfer coefficient can be conveniently calibrated by test, and this kind of sensors has no obvious priority design parameters. Improved calibration test is put forward to enhance the accuracy of the calibration coefficient of end-expanding sensors. By considering the practical state of sensors and the testing accuracy, comprehensive and systematic analyses on optical fiber sensors are provided from the perspective of mechanical actions, which could scientifically instruct the application design and calibration test of industrialized optical fiber sensors.

  14. [New type distributed optical fiber temperature sensor (DTS) based on Raman scattering and its' application].

    Science.gov (United States)

    Wang, Jian-Feng; Liu, Hong-Lin; Zhang, Shu-Qin; Yu, Xiang-Dong; Sun, Zhong-Zhou; Jin, Shang-Zhong; Zhang, Zai-Xuan

    2013-04-01

    Basic principles, development trends and applications status of distributed optical fiber Raman temperature sensor (DTS) are introduced. Performance parameters of DTS system include the sensing optical fiber length, temperature measurement uncertainty, spatial resolution and measurement time. These parameters have a certain correlation and it is difficult to improve them at the same time by single technology. So a variety of key techniques such as Raman amplification, pulse coding technique, Raman related dual-wavelength self-correction technique and embedding optical switching technique are researched to improve the performance of the DTS system. A 1 467 nm continuous laser is used as pump laser and the light source of DTS system (1 550 nm pulse laser) is amplified. When the length of sensing optical fiber is 50 km the Raman gain is about 17 dB. Raman gain can partially compensate the transmission loss of optical fiber, so that the sensing length can reach 50 km. In DTS system using pulse coding technique, pulse laser is coded by 211 bits loop encoder and correlation calculation is used to demodulate temperature. The encoded laser signal is related, whereas the noise is not relevant. So that signal-to-noise ratio (SNR) of DTS system can be improved significantly. The experiments are carried out in DTS system with single mode optical fiber and multimode optical fiber respectively. Temperature measurement uncertainty can all reach 1 degrees C. In DTS system using Raman related dual-wavelength self-correction technique, the wavelength difference of the two light sources must be one Raman frequency shift in optical fiber. For example, wavelength of the main laser is 1 550 nm and wavelength of the second laser must be 1 450 nm. Spatial resolution of DTS system is improved to 2 m by using dual-wavelength self-correction technique. Optical switch is embedded in DTS system, so that the temperature measurement channel multiply extended and the total length of the sensing

  15. Process monitoring with optical fibers and harsh environment sensors

    International Nuclear Information System (INIS)

    Marcus, M.A.; Wang, A.

    1999-01-01

    This volume contains 35 papers presented at the symposium. Some of the topics covered are: sensors for the energy industry; sensors for materials evaluation and structural monitoring; sensors for engine industry; and other harsh environments sensors

  16. Highly Sensitive and Wide-Dynamic-Range Multichannel Optical-Fiber pH Sensor Based on PWM Technique.

    Science.gov (United States)

    Khan, Md Rajibur Rahaman; Kang, Shin-Won

    2016-11-09

    In this study, we propose a highly sensitive multichannel pH sensor that is based on an optical-fiber pulse width modulation (PWM) technique. According to the optical-fiber PWM method, the received sensing signal's pulse width changes when the optical-fiber pH sensing-element of the array comes into contact with pH buffer solutions. The proposed optical-fiber PWM pH-sensing system offers a linear sensing response over a wide range of pH values from 2 to 12, with a high pH-sensing ability. The sensitivity of the proposed pH sensor is 0.46 µs/pH, and the correlation coefficient R² is approximately 0.997. Additional advantages of the proposed optical-fiber PWM pH sensor include a short/fast response-time of about 8 s, good reproducibility properties with a relative standard deviation (RSD) of about 0.019, easy fabrication, low cost, small size, reusability of the optical-fiber sensing-element, and the capability of remote sensing. Finally, the performance of the proposed PWM pH sensor was compared with that of potentiometric, optical-fiber modal interferometer, and optical-fiber Fabry-Perot interferometer pH sensors with respect to dynamic range width, linearity as well as response and recovery times. We observed that the proposed sensing systems have better sensing abilities than the above-mentioned pH sensors.

  17. Optical Fiber Sensors For Monitoring Joint Articulation And Chest Expansion Of A Human Body

    Science.gov (United States)

    Muhs, Jeffrey D.; Allison, Stephen W.

    1997-12-23

    Fiber-optic sensors employing optical fibers of elastomeric material are incorporated in devices adapted to be worn by human beings in joint and chest regions for the purpose of monitoring and measuring the extent of joint articulation and chest expansion especially with respect to time.

  18. Two-Channel SPR Sensor Combined Application of Polymer- and Vitreous-Clad Optic Fibers.

    Science.gov (United States)

    Wei, Yong; Su, Yudong; Liu, Chunlan; Nie, Xiangfei; Liu, Zhihai; Zhang, Yu; Zhang, Yonghui

    2017-12-09

    By combining a polymer-clad optic fiber and a vitreous-clad optic fiber, we proposed and fabricated a novel optic fiber surface plasmon resonance (SPR) sensor to conduct two-channel sensing at the same detection area. The traditional optic fiber SPR sensor has many disadvantages; for example, removing the cladding requires corrosion, operating it is dangerous, adjusting the dynamic response range is hard, and producing different resonance wavelengths in the sensing area to realize a multi-channel measurement is difficult. Therefore, in this paper, we skillfully used bare fiber grinding technology and reverse symmetry welding technology to remove the cladding in a multi-mode fiber and expose the evanescent field. On the basis of investigating the effect of the grinding angle on the dynamic range change of the SPR resonance valley wavelength and sensitivity, we combined polymer-clad fiber and vitreous-clad fiber by a smart design structure to realize at a single point a two-channel measurement fiber SPR sensor. In this paper, we obtained a beautiful spectral curve from a multi-mode fiber two-channel SPR sensor. In the detection range of the refractive rate between 1.333 RIU and 1.385 RIU, the resonance valley wavelength of channel Ⅰ shifted from 622 nm to 724 nm with a mean average sensitivity of 1961 nm/RIU and the resonance valley wavelength of channel Ⅱ shifted from 741 nm to 976 nm with a mean average sensitivity of 4519 nm/RIU.

  19. Compound parabolic concentrator optical fiber tip for FRET-based fluorescent sensors

    DEFF Research Database (Denmark)

    Hassan, Hafeez Ul; Nielsen, Kristian; Aasmul, Soren

    2015-01-01

    The Compound Parabolic Concentrator (CPC) optical fiber tip shape has been proposed for intensity based fluorescent sensors working on the principle of FRET (Förster Resonance Energy Transfer). A simple numerical Zemax model has been used to optimize the CPC tip geometry for a step-index multimode...... polymer optical fiber for an excitation and emission wavelength of 550 nm and 650nm, respectively. The model suggests an increase of a factor of 1.6 to 4 in the collected fluorescent power for an ideal CPC tip, as compared to the plane-cut fiber tip for fiber lengths between 5 and 45mm...

  20. A Polymer Optical Fiber Fuel Level Sensor: Application to Paramotoring and Powered Paragliding

    Directory of Open Access Journals (Sweden)

    David Sánchez Montero

    2012-05-01

    Full Text Available A low-cost intensity-based polymer optical fiber (POF sensor for fuel level measurements in paramotoring and powered paragliding is presented, exploiting the advantages of the optical fiber sensing technology. Experimental results demonstrate that the best option can be performed by stripping the fiber at the desired discrete points to measure the fuel level as well as with a gauge-shape fiber bending. The prototype has a good linearity, better than 4% full scale (F.S., and sensitivity around 0.5 V per bend are obtained. Hysteresis due to residual fluid at the sensing points is found to be less than 9% F.S.

  1. Experimental investigation of optical fiber temperature sensors at cryogenic temperature and in high magnetic fields

    International Nuclear Information System (INIS)

    Tanaka, Y.; Ogata, M.; Nagashima, K.; Agawa, H.; Matsuura, S.; Kumagai, Y.

    2010-01-01

    If it is possible to monitor the conditions in the cryogenic equipments including the super-conducting magnets, the indication of failure can be detected beforehand and the reliability in the operation can improve. Optical fiber temperature sensing is an advantageous method in terms of heat invasion, electric insulation, etc. Therefore, the experiments which confirm the characteristics of optical fiber temperature sensors at cryogenic temperatures and in high magnetic fields were performed, and the possibility of measuring under these conditions was confirmed. However, since the resolution of temperature was a problem, the method of analysis that predicts the measurements was contrived, and the method to improve the problem was examined.

  2. Optical fiber sensors: Systems and applications. Volume 2

    Science.gov (United States)

    Culshaw, Brian; Dakin, John

    State-of-the-art fiber-optic (FO) sensors and their applications are described in chapters contributed by leading experts. Consideration is given to interferometers, FO gyros, intensity- and wavelength-based sensors and optical actuators, Si in FO sensors, point-sensor multiplexing principles, and distributed FO sensor systems. Also examined are chemical, biochemical, and medical sensors; physical and chemical sensors for process control; FO-sensor applications in the marine and aerospace industries; FO-sensor monitoring systems for security and safety, structural integrity, NDE, and the electric-power industry; and the market situation for FO-sensor technology. Diagrams, drawings, graphs, and photographs are provided.

  3. Improving the durability of the optical fiber sensor based on strain transfer analysis

    Science.gov (United States)

    Wang, Huaping; Jiang, Lizhong; Xiang, Ping

    2018-05-01

    To realize the reliable and long-term strain detection, the durability of optical fiber sensors has attracted more and more attention. The packaging technique has been considered as an effective method, which can enhance the survival ratios of optical fiber sensors to resist the harsh construction and service environment in civil engineering. To monitor the internal strain of structures, the embedded installation is adopted. Due to the different material properties between host material and the protective layer, the monitored structure embedded with sensors can be regarded as a typical model containing inclusions. Interfacial characteristic between the sensor and host material exists obviously, and the contacted interface is prone to debonding failure induced by the large interfacial shear stress. To recognize the local interfacial debonding damage and extend the effective life cycle of the embedded sensor, strain transfer analysis of a general three-layered sensing model is conducted to investigate the failure mechanism. The perturbation of the embedded sensor on the local strain field of host material is discussed. Based on the theoretical analysis, the distribution of the interfacial shear stress along the sensing length is characterized and adopted for the diagnosis of local interfacial debonding, and the sensitive parameters influencing the interfacial shear stress are also investigated. The research in this paper explores the interfacial debonding failure mechanism of embedded sensors based on the strain transfer analysis and provides theoretical basis for enhancing the interfacial bonding properties and improving the durability of embedded optical fiber sensors.

  4. Highly Sensitive and Wide-Dynamic-Range Multichannel Optical-Fiber pH Sensor Based on PWM Technique

    OpenAIRE

    Md. Rajibur Rahaman Khan; Shin-Won Kang

    2016-01-01

    In this study, we propose a highly sensitive multichannel pH sensor that is based on an optical-fiber pulse width modulation (PWM) technique. According to the optical-fiber PWM method, the received sensing signal?s pulse width changes when the optical-fiber pH sensing-element of the array comes into contact with pH buffer solutions. The proposed optical-fiber PWM pH-sensing system offers a linear sensing response over a wide range of pH values from 2 to 12, with a high pH-sensing ability. The...

  5. Turbidimeter Design and Analysis: A Review on Optical Fiber Sensors for the Measurement of Water Turbidity

    Science.gov (United States)

    Omar, Ahmad Fairuz Bin; MatJafri, Mohd Zubir Bin

    2009-01-01

    Turbidimeters operate based on the optical phenomena that occur when incident light through water body is scattered by the existence of foreign particles which are suspended within it. This review paper elaborates on the standards and factors that may influence the measurement of turbidity. The discussion also focuses on the optical fiber sensor technologies that have been applied within the lab and field environment and have been implemented in the measurement of water turbidity and concentration of particles. This paper also discusses and compares results from three different turbidimeter designs that use various optical components. Mohd Zubir and Bashah and Daraigan have introduced a design which has simple configurations. Omar and MatJafri, on the other hand, have established a new turbidimeter design that makes use of optical fiber cable as the light transferring medium. The application of fiber optic cable to the turbidimeter will present a flexible measurement technique, allowing measurements to be made online. Scattered light measurement through optical fiber cable requires a highly sensitive detector to interpret the scattered light signal. This has made the optical fiber system have higher sensitivity in measuring turbidity compared to the other two simple turbidimeters presented in this paper. Fiber optic sensors provide the potential for increased sensitivity over large concentration ranges. However, many challenges must be examined to develop sensors that can collect reliable turbidity measurements in situ. PMID:22408507

  6. Turbidimeter Design and Analysis: A Review on Optical Fiber Sensors for the Measurement of Water Turbidity

    Directory of Open Access Journals (Sweden)

    Mohd Zubir Bin MatJafri

    2009-10-01

    Full Text Available Turbidimeters operate based on the optical phenomena that occur when incident light through water body is scattered by the existence of foreign particles which are suspended within it. This review paper elaborates on the standards and factors that may influence the measurement of turbidity. The discussion also focuses on the optical fiber sensor technologies that have been applied within the lab and field environment and have been implemented in the measurement of water turbidity and concentration of particles. This paper also discusses and compares results from three different turbidimeter designs that use various optical components. Mohd Zubir and Bashah and Daraigan have introduced a design which has simple configurations. Omar and MatJafri, on the other hand, have established a new turbidimeter design that makes use of optical fiber cable as the light transferring medium. The application of fiber optic cable to the turbidimeter will present a flexible measurement technique, allowing measurements to be made online. Scattered light measurement through optical fiber cable requires a highly sensitive detector to interpret the scattered light signal. This has made the optical fiber system have higher sensitivity in measuring turbidity compared to the other two simple turbidimeters presented in this paper. Fiber optic sensors provide the potential for increased sensitivity over large concentration ranges. However, many challenges must be examined to develop sensors that can collect reliable turbidity measurements in situ.

  7. Bullet Optical Fiber Humidity Sensor Based on Ag Nanoparticles Dispersed in Leaf Extract of Alstonia Scholaris

    Directory of Open Access Journals (Sweden)

    Anu VIJAYAN

    2008-05-01

    Full Text Available An optical fiber with a clad of Ag nanoparticles dispersed in leaf extract of Alstonia Scholaris is used as an optical humidity sensor. The fabricated sensor showed response to humidity in the range of 40-95%. The specialty of this sensor is that it can be used when stored at room temperature (25 oC up to a maximum of 25 days with 90% retention of original sensitivity. These humidity sensing bio-films showed good operational efficiency for 5 cycles. The plastic optical fiber is versatile and can be used easily for humidity measurement with high sensitivity. The sensor exhibited a short response time of 4-5 sec. and recovery time of 45 sec with repeatability, reproducibility and low hysteresis effect. This Ag dispersed in leaf extract of Alstonia Scholaris showed higher humidity response compared to response shown by the leaf extract alone.

  8. Small biomolecule immunosensing with plasmonic optical fiber grating sensor.

    Science.gov (United States)

    Ribaut, Clotilde; Voisin, Valérie; Malachovská, Viera; Dubois, Valentin; Mégret, Patrice; Wattiez, Ruddy; Caucheteur, Christophe

    2016-03-15

    This study reports on the development of a surface plasmon resonance (SPR) optical fiber biosensor based on tilted fiber Bragg grating technology for direct detection of small biomarkers of interest for lung cancer diagnosis. Since SPR principle relies on the refractive index modifications to sensitively detect mass changes at the gold coated surface, we have proposed here a comparative study in relation to the target size. Two cytokeratin 7 (CK7) samples with a molecular weight ranging from 78 kDa to 2.6 kDa, respectively CK7 full protein and CK7 peptide, have been used for label-free monitoring. This work has first consisted in the elaboration and the characterization of a robust and reproducible bioreceptor, based on antibody/antigen cross-linking. Immobilized antibodies were then utilized as binding agents to investigate the sensitivity of the biosensor towards the two CK7 antigens. Results have highlighted a very good sensitivity of the biosensor response for both samples diluted in phosphate buffer with a higher limit of detection for the larger CK7 full protein. The most groundbreaking nature of this study relies on the detection of small biomolecule CK7 peptides in buffer and in the presence of complex media such as serum, achieving a limit of detection of 0.4 nM. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Distributed Long-Gauge Optical Fiber Sensors Based Self-Sensing FRP Bar for Concrete Structure

    OpenAIRE

    Tang, Yongsheng; Wu, Zhishen

    2016-01-01

    Brillouin scattering-based distributed optical fiber (OF) sensing technique presents advantages for concrete structure monitoring. However, the existence of spatial resolution greatly decreases strain measurement accuracy especially around cracks. Meanwhile, the brittle feature of OF also hinders its further application. In this paper, the distributed OF sensor was firstly proposed as long-gauge sensor to improve strain measurement accuracy. Then, a new type of self-sensing fiber reinforced p...

  10. Strain transfer analysis of optical fiber based sensors embedded in an asphalt pavement structure

    International Nuclear Information System (INIS)

    Wang, Huaping; Xiang, Ping

    2016-01-01

    Asphalt pavement is vulnerable to random damage, such as cracking and rutting, which can be proactively identified by distributed optical fiber sensing technology. However, due to the material nature of optical fibers, a bare fiber is apt to be damaged during the construction process of pavements. Thus, a protective layer is needed for this application. Unfortunately, part of the strain of the host material is absorbed by the protective layer when transferring the strain to the sensing fiber. To account for the strain transfer error, in this paper a theoretical analysis of the strain transfer of a three-layered general model has been carried out by introducing Goodman’s hypothesis to describe the interfacial shear stress relationship. The model considers the viscoelastic behavior of the host material and protective layer. The effects of one crack in the host material and the sensing length on strain transfer relationship are been discussed. To validate the effectiveness of the strain transfer analysis, a flexible asphalt-mastic packaged distributed optical fiber sensor was designed and tested in a laboratory environment to monitor the distributed strain and appearance of cracks in an asphalt concrete beam at two different temperatures. The experimental results indicated that the developed strain transfer formula can significantly reduce the strain transfer error, and that the asphalt-mastic packaged optical fiber sensor can successfully monitor the distributed strain and identify local cracks. (paper)

  11. Strain transfer analysis of optical fiber based sensors embedded in an asphalt pavement structure

    Science.gov (United States)

    Wang, Huaping; Xiang, Ping

    2016-07-01

    Asphalt pavement is vulnerable to random damage, such as cracking and rutting, which can be proactively identified by distributed optical fiber sensing technology. However, due to the material nature of optical fibers, a bare fiber is apt to be damaged during the construction process of pavements. Thus, a protective layer is needed for this application. Unfortunately, part of the strain of the host material is absorbed by the protective layer when transferring the strain to the sensing fiber. To account for the strain transfer error, in this paper a theoretical analysis of the strain transfer of a three-layered general model has been carried out by introducing Goodman’s hypothesis to describe the interfacial shear stress relationship. The model considers the viscoelastic behavior of the host material and protective layer. The effects of one crack in the host material and the sensing length on strain transfer relationship are been discussed. To validate the effectiveness of the strain transfer analysis, a flexible asphalt-mastic packaged distributed optical fiber sensor was designed and tested in a laboratory environment to monitor the distributed strain and appearance of cracks in an asphalt concrete beam at two different temperatures. The experimental results indicated that the developed strain transfer formula can significantly reduce the strain transfer error, and that the asphalt-mastic packaged optical fiber sensor can successfully monitor the distributed strain and identify local cracks.

  12. Fabrication and Analysis Signal Optical Fiber Sensor Based On Bend Loss for Weight in Motion Applications

    Science.gov (United States)

    Aftah Syukron, Ahmad; Marzuki, Ahmad; Setyawan, Ary

    2017-11-01

    Road network plays very important role in economic development. Overweight is one of the main factors contributing to road damage. To minimize this factor, road authority has to make sure that all vehicles operate in according to maximum vehicle regulation set by the government. The one solution can use from this problem is Weight in motion (WIM) technology. WIM technology allows measuring vehicle weight quickly. The sensor is one of the important components in the WIM system. This paper presents a model of WIM fiber sensor work based on bend loss. Fiber sensor has made by coiling optical fiber. Coiling optical fiber has managed in the elliptical shape rubber coil. Rubber coil then is planted in the pad of sensor. The principle of this sensor is a detecting of the shift light intensity output of optical fiber when the vehicles a passing through on fiber sensor. Loading was carried out using loaded truck model. Data was carried out with variations of load and load positions in the truck. The results can be concluded that the shift light intensity is greater with the more shift loads. The loader of the truck has also resulted in the greater loss. Loads in the truck distributed on the axles due to the position of loads.

  13. Design and Optimization of Dual Optical Fiber MEMS Pressure Sensor For Biomedical Applications

    International Nuclear Information System (INIS)

    Dagang, Guo; Po, Samuel Ng Choon; Hock, Francis Tay Eng; Rongming, Lin

    2006-01-01

    A novel Single Deeply Corrugated Diaphragm (SDCD) based dual optical fiber Fabry-Perot pressure sensor for blood pressure measurement is proposed. Both mechanical and optical simulations are performed to demonstrate the feasibility and superior performance of the proposed sensor. Result shows that less than 2% nonlinearity can be achieved for the proposed sensor using optimal Fabry-Perot microcavity. Also, the fabrication process of the proposed sensor is given, instead of complicated fusion bonding process, only bulk and surface micromachining techniques are required which facilitate the mass production of such biocompatible and disposable pressure sensors

  14. A Temperature Sensor Based on a Polymer Optical Fiber Macro-Bend

    Directory of Open Access Journals (Sweden)

    Joseba Zubia Zaballa

    2013-09-01

    Full Text Available The design and development of a plastic optical fiber (POF macrobend temperature sensor is presented. The sensor has a linear response versus temperature at a fixed bend radius, with a sensitivity of . The sensor system used a dummy fiber-optic sensor for reference purposes having a resolution below 0.3 °C. A comprehensive experimental analysis was carried out to provide insight into the effect of different surrounding media on practical macro-bend POF sensor implementation. Experimental results are successfully compared with bend loss calculations.

  15. A Temperature Sensor Based on a Polymer Optical Fiber Macro-Bend

    Science.gov (United States)

    Moraleda, Alberto Tapetado; García, Carmen Vázquez; Zaballa, Joseba Zubia; Arrue, Jon

    2013-01-01

    The design and development of a plastic optical fiber (POF) macrobend temperature sensor is presented. The sensor has a linear response versus temperature at a fixed bend radius, with a sensitivity of 1.92·10−3 (°C)−1. The sensor system used a dummy fiber-optic sensor for reference purposes having a resolution below 0.3 °C. A comprehensive experimental analysis was carried out to provide insight into the effect of different surrounding media on practical macro-bend POF sensor implementation. Experimental results are successfully compared with bend loss calculations. PMID:24077323

  16. Recent progress in distributed optical fiber Raman photon sensors at China Jiliang University

    Science.gov (United States)

    Zhang, Zaixuan; Wang, Jianfeng; Li, Yi; Gong, Huaping; Yu, Xiangdong; Liu, Honglin; Jin, Yongxing; Kang, Juan; Li, Chenxia; Zhang, Wensheng; Zhang, Wenping; Niu, Xiaohui; Sun, Zhongzhou; Zhao, Chunliu; Dong, Xinyong; Jin, Shangzhong

    2012-06-01

    A brief review of recent progress in researches, productions and applications of full distributed fiber Raman photon sensors at China Jiliang University (CJLU) is presented. In order to improve the measurement distance, the accuracy, the space resolution, the ability of multi-parameter measurements, and the intelligence of full distributed fiber sensor systems, a new generation fiber sensor technology based on the optical fiber nonlinear scattering fusion principle is proposed. A series of new generation full distributed fiber sensors are investigated and designed, which consist of new generation ultra-long distance full distributed fiber Raman and Rayleigh scattering photon sensors integrated with a fiber Raman amplifier, auto-correction full distributed fiber Raman photon temperature sensors based on Raman correlation dual sources, full distributed fiber Raman photon temperature sensors based on a pulse coding source, full distributed fiber Raman photon temperature sensors using a fiber Raman wavelength shifter, a new type of Brillouin optical time domain analyzers (BOTDAs) integrated with a fiber Raman amplifier for replacing a fiber Brillouin amplifier, full distributed fiber Raman and Brillouin photon sensors integrated with a fiber Raman amplifier, and full distributed fiber Brillouin photon sensors integrated with a fiber Brillouin frequency shifter. The Internet of things is believed as one of candidates of the next technological revolution, which has driven hundreds of millions of class markets. Sensor networks are important components of the Internet of things. The full distributed optical fiber sensor network (Rayleigh, Raman, and Brillouin scattering) is a 3S (smart materials, smart structure, and smart skill) system, which is easy to construct smart fiber sensor networks. The distributed optical fiber sensor can be embedded in the power grids, railways, bridges, tunnels, roads, constructions, water supply systems, dams, oil and gas pipelines and other

  17. Optical fiber relative humidity sensor based on a FBG with a di-ureasil coating.

    Science.gov (United States)

    Correia, Sandra F H; Antunes, Paulo; Pecoraro, Edison; Lima, Patrícia P; Varum, Humberto; Carlos, Luis D; Ferreira, Rute A S; André, Paulo S

    2012-01-01

    In this work we proposed a relative humidity (RH) sensor based on a Bragg grating written in an optical fiber, associated with a coating of organo-silica hybrid material prepared by the sol-gel method. The organo-silica-based coating has a strong adhesion to the optical fiber and its expansion is reversibly affected by the change in the RH values (15.0-95.0%) of the surrounding environment, allowing an increased sensitivity (22.2 pm/%RH) and durability due to the presence of a siliceous-based inorganic component. The developed sensor was tested in a real structure health monitoring essay, in which the RH inside two concrete blocks with different porosity values was measured over 1 year. The results demonstrated the potential of the proposed optical sensor in the monitoring of civil engineering structures.

  18. Fast and accurate determination of the detergent efficiency by optical fiber sensors

    Science.gov (United States)

    Patitsa, Maria; Pfeiffer, Helge; Wevers, Martine

    2011-06-01

    An optical fiber sensor was developed to control the cleaning efficiency of surfactants. Prior to the measurements, the sensing part of the probe is covered with a uniform standardized soil layer (lipid multilayer), and a gold mirror is deposited at the end of the optical fiber. For the lipid multilayer deposition on the fiber, Langmuir-Blodgett technique was used and the progress of deposition was followed online by ultraviolet spectroscopy. The invention provides a miniaturized Surface Plasmon Resonance dip-sensor for automated on-line testing that can replace the cost and time consuming existing methods and develop a breakthrough in detergent testing in combining optical sensing, surface chemistry and automated data acquisition. The sensor is to be used to evaluate detergency of different cleaning products and also indicate how formulation, concentration, lipid nature and temperature affect the cleaning behavior of a surfactant.

  19. Multimode-singlemode-multimode optical fiber sensor coated with novolac resin for detecting liquid phase alcohol

    Science.gov (United States)

    Marfu'ah, Amalia, Niza Rosyda; Hatta, Agus Muhamad; Pratama, Detak Yan

    2018-04-01

    Alcohol sensor based on multimode-singlemode-multimode (MSM) optical fiber with novolac resin as the external medium is proposed and demonstrated experimentally. Novolac resin swells when it is exposed by the alcohol. This effect causes a change in the polymer density leading to the refractive index's variation. The transmission light of the sensor depends on the refractive index of external medium. Based on the results, alcohol sensor based on MSM optical fiber structure using novolac resin has a higher sensitivity compared to the sensor without using novolac resin in the mixture of alcohol and distilled water. Alcohol sensor based on MSM optical fiber structure using novolac resin in the mixture of alcohol and distilled water with a singlemode fiber length of 5 mm has a sensitivity of 0.028972 dBm per % V/V, and in the mixture of alcohol and sugar solution of 10% w/w has a sensitivity of 0.005005 dBm per % V/V.

  20. Sensitive zone parameters and curvature radius evaluation for polymer optical fiber curvature sensors

    Science.gov (United States)

    Leal-Junior, Arnaldo G.; Frizera, Anselmo; José Pontes, Maria

    2018-03-01

    Polymer optical fibers (POFs) are suitable for applications such as curvature sensors, strain, temperature, liquid level, among others. However, for enhancing sensitivity, many polymer optical fiber curvature sensors based on intensity variation require a lateral section. Lateral section length, depth, and surface roughness have great influence on the sensor sensitivity, hysteresis, and linearity. Moreover, the sensor curvature radius increase the stress on the fiber, which leads on variation of the sensor behavior. This paper presents the analysis relating the curvature radius and lateral section length, depth and surface roughness with the sensor sensitivity, hysteresis and linearity for a POF curvature sensor. Results show a strong correlation between the decision parameters behavior and the performance for sensor applications based on intensity variation. Furthermore, there is a trade-off among the sensitive zone length, depth, surface roughness, and curvature radius with the sensor desired performance parameters, which are minimum hysteresis, maximum sensitivity, and maximum linearity. The optimization of these parameters is applied to obtain a sensor with sensitivity of 20.9 mV/°, linearity of 0.9992 and hysteresis below 1%, which represent a better performance of the sensor when compared with the sensor without the optimization.

  1. Optical fiber sensor of partial discharges in High Voltage DC experiments

    Science.gov (United States)

    Búa-Núñez, I.; Azcárraga-Ramos, C. G.; Posada-Román, J. E.; Garcia-Souto, J. A.

    2014-05-01

    A setup simulating High Voltage DC (HVDC) transformers barriers was developed to demonstrate the effectiveness of an optical fiber (OF) sensor in detecting partial discharges (PD) under these peculiar conditions. Different PD detection techniques were compared: electrical methods, and acoustic methods. Standard piezoelectric sensors (R15i-AST) and the above mentioned OF sensors were used for acoustic detection. The OF sensor was able to detect PD acoustically with a sensitivity better than the other detection methods. The multichannel instrumentation system was tested in real HVDC conditions with the aim of analyzing the behavior of the insulation (mineral oil/pressboard).

  2. Design, Manufacturing and Experimental Validation of Optical Fiber Sensors Based Devices for Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    Angela CORICCIATI

    2016-06-01

    Full Text Available The use of optical fiber sensors is a promising and rising technique used for Structural Health Monitoring (SHM, because permit to monitor continuously the strain and the temperature of the structure where they are applied. In the present paper three different types of smart devices, that are composite materials with an optical fiber sensor embedded inside them during the manufacturing process, are described: Smart Patch, Smart Rebar and Smart Textile, which are respectively a plate for local exterior intervention, a rod for shear and flexural interior reinforcement and a textile for an external whole application. In addition to the monitoring aim, the possible additional function of these devices could be the reinforcement of the structures where they are applied. In the present work, after technology manufacturing description, the experimental laboratory characterization of each device is discussed. At last, smart devices application on medium scale masonry walls and their validation by mechanical tests is described.

  3. Tapered Optical Fiber Sensor for Detection of pH in Microscopic Volumes

    Directory of Open Access Journals (Sweden)

    Ondřej PODRAZKÝ

    2014-05-01

    Full Text Available A compact and robust tapered optical fiber microsensor is presented for detection of pH in a range from 5.8 to 7.5 in sub-microliter volumes. The sensor is based on a pH transducer 8- hydroxypyrene-1,3,6-trisulfonic acid trisodium salt immobilized in a xerogel matrix onto the tip of a optical fiber taper with a tip diameter below 20 mm. The sol-gel method and two silicon alkoxides is used for preparing the matrix. A ratio of the fluorescence emission intensities measured at 518 nm after the excitation at 400 and 450 nm is used for evaluating the sensor response to pH. This ratiometric approach enables to reduce effects of ambient light, bleaching of the sensitive layer and geometry of the probe to the fluorescence signal and achieve the resolution of about 0.07 pH units.

  4. Optical fiber sensors fabricated by the focused ion beam technique

    DEFF Research Database (Denmark)

    Yuan, Scott Wu; Wang, Fei; Bang, Ole

    2012-01-01

    crystal fiber (PCF). Using this technique we fabricate a highly compact fiber-optic Fabry-Pérot (FP) refractive index sensor near the tip of fiber taper, and a highly sensitive in-line temperature sensor in PCF. We also demonstrate the potential of using FIB to selectively fill functional fluid......Focused ion beam (FIB) is a highly versatile technique which helps to enable next generation of lab-on-fiber sensor technologies. In this paper, we demonstrate the use application of FIB to precisely mill the fiber taper and end facet of both conventional single mode fiber (SMF) and photonic...

  5. Testing of Sapphire Optical Fiber and Sensors in Intense Radiation Fields When Subjected to Very High Temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Blue, Thomas [The Ohio State Univ., Columbus, OH (United States); Windl, Wolfgang [The Ohio State Univ., Columbus, OH (United States)

    2017-12-15

    The primary objective of this project was to determine the optical attenuation and signal degradation of sapphire optical fibers & sensors (temperature & strain), in-situ, operating at temperatures up to 1500°C during reactor irradiation through experiments and modeling. The results will determine the feasibility of extending sapphire optical fiber-based instrumentation to extremely high temperature radiation environments. This research will pave the way for future testing of sapphire optical fibers and fiber-based sensors under conditions expected in advanced high temperature reactors.

  6. Two-Channel SPR Sensor Combined Application of Polymer- and Vitreous-Clad Optic Fibers

    Directory of Open Access Journals (Sweden)

    Yong Wei

    2017-12-01

    Full Text Available By combining a polymer-clad optic fiber and a vitreous-clad optic fiber, we proposed and fabricated a novel optic fiber surface plasmon resonance (SPR sensor to conduct two-channel sensing at the same detection area. The traditional optic fiber SPR sensor has many disadvantages; for example, removing the cladding requires corrosion, operating it is dangerous, adjusting the dynamic response range is hard, and producing different resonance wavelengths in the sensing area to realize a multi-channel measurement is difficult. Therefore, in this paper, we skillfully used bare fiber grinding technology and reverse symmetry welding technology to remove the cladding in a multi-mode fiber and expose the evanescent field. On the basis of investigating the effect of the grinding angle on the dynamic range change of the SPR resonance valley wavelength and sensitivity, we combined polymer-clad fiber and vitreous-clad fiber by a smart design structure to realize at a single point a two-channel measurement fiber SPR sensor. In this paper, we obtained a beautiful spectral curve from a multi-mode fiber two-channel SPR sensor. In the detection range of the refractive rate between 1.333 RIU and 1.385 RIU, the resonance valley wavelength of channel Ⅰ shifted from 622 nm to 724 nm with a mean average sensitivity of 1961 nm/RIU and the resonance valley wavelength of channel Ⅱ shifted from 741 nm to 976 nm with a mean average sensitivity of 4519 nm/RIU.

  7. Improved response time of laser etched polymer optical fiber Bragg grating humidity sensor

    OpenAIRE

    Zhang, Wei; Chen, Xianfeng; Liu, Chen; Lu, Yuanfu; Cardoso, Marcos; Webb, David J.

    2015-01-01

    The humidity sensor made of polymer optical fiber Bragg grating (POFBG) responds to the water content change in fiber induced by the change of environmental condition. The response time strongly depends on fiber size as the water change is a diffusion process. The ultra short laser pulses have been providing an effective micro fabrication method to achieve spatial localized modification in materials. In this work we used the excimer laser to create different microstructures (slot, D-shape) in...

  8. Refractive index sensor based on optical fiber end face using pulse reference-based compensation technique

    Science.gov (United States)

    Bian, Qiang; Song, Zhangqi; Zhang, Xueliang; Yu, Yang; Chen, Yuzhong

    2018-03-01

    We proposed a refractive index sensor based on optical fiber end face using pulse reference-based compensation technique. With good compensation effect of this compensation technique, the power fluctuation of light source, the change of optic components transmission loss and coupler splitting ratio can be compensated, which largely reduces the background noise. The refractive index resolutions can achieve 3.8 × 10-6 RIU and1.6 × 10-6 RIU in different refractive index regions.

  9. OPTICAL FIBER SENSOR TECHNOLOGIES FOR EFFICIENT AND ECONOMICAL OIL RECOVERY

    Energy Technology Data Exchange (ETDEWEB)

    A. Wang; H. Xiao; R. May

    1999-10-29

    Efficient and complete recovery of petroleum reserves from existing oil wells has proven difficult due to a lack of robust instrumentation that can monitor processes in the downhole environment. Commercially available sensors for measurement of pressure, temperature, and fluid flow exhibit shortened lifetimes in the harsh downhole conditions, which are characterized by high pressures (up to 20 kpsi), temperatures up to 250 C, and exposure to chemically reactive fluids. Development of robust sensors that deliver continuous, real-time data on reservoir performance and petroleum flow pathways will facilitate application of advanced recovery technologies, including horizontal and multi-lateral wells. The main objective of the research program is to develop cost-effective, reliable fiber sensor instrumentation for real-time monitoring and /or control of various key parameters crucial to efficient and economical oil production. This report presents the detailed research work and technical progress from October 1, 1998 to September 30, 1999. The research performed over the first year of the program has followed the schedule as proposed, and solid research progress has been made in specification of the technical requirements, design and fabrication of the SCIIB sensor probes, development of the sensor systems, development of DSP-based signal processing techniques, and construction of the test systems. These technical achievements will significantly help to advance continued research on sensor tests and evaluation during the second year of the program.

  10. An IFPI Temperature Sensor Fabricated in an Unstriped Optical Fiber with Self-Strain-Compensation Function

    Directory of Open Access Journals (Sweden)

    Yang Song

    2016-01-01

    Full Text Available This paper describes an intrinsic Fabry-Perot interferometer (IFPI temperature sensor with self-strain-compensation function. The sensor was fabricated on a buffer-intact optical fiber using a femtosecond (fs laser system. The use of fs laser allows the sensor to be fabricated in an optical fiber without the necessity of removing the polymer buffer coating, thus not compromising its mechanical property. The sensor is composed of two cascaded IFPIs in different cavity length of 100 μm and 500 μm, respectively. The shorter IFPI serves as the temperature sensor, while the second IFPI serves as a compensation sensor, which is used to decouple the strain from the raw signal collected by the shorter FPI. The reflection spectrum of sensor, containing both sensory information and compensation information, is collected in wavelength domain and demultiplexed in the Fourier domain of reflection spectrum. An algorithm was developed and successfully implemented to compensate the strain influence on the proposed temperature sensor. The results showed that the proposed sensor structure holds a constant temperature sensitivity of 11.33 pm/°C when strained differently.

  11. Geomembranes with incorporated optical fiber sensors for geotechnical and environmental applications

    International Nuclear Information System (INIS)

    Borns, D.J.

    1997-01-01

    This research covers the development of optical-fiber sensors and the methods to incorporate the sensors within geomembranes during manufacture. Such systems are being developed to monitor the effects of strain on geomembranes including the location of tears. Other possible measurements utilize moisture and fluid-level sensors. Since the use of geomembranes in geotechnical and environmental applications is widespread and monitoring systems are generally lacking, the potential for this technology is significant. For example, a geomembrane-and-sensor system addresses the need to monitor landfill stabilization in general and specifically the behavior of geomembranes used in liner and cover designs. We have demonstrated that glass and plastic fibers can be attached to a geomembrane (1) during extrusion and lamination and (2) by hot shoe welding, glued tape runners, and welded runners. Using these methods, we have manufactured 30 m lengths of geomembrane with continuous optical Fiber across the length. Our preliminary focus has been on strain sensors to monitor landfill subsidence. We have utilized existing and newly developed strain sensors, e.g., microbend, Bragg grating, and adsorption band sensors. These sensors have been installed as arrays into several test membranes at a manufacturing scale (e.g., 3 to 4 m wide). The prototype monitoring systems were installed in laboratory test frames, and the sensors measured the strains across the membranes as they were loaded. We plan to scale these experiments up to the size of landfill cover system using a test cell under construction

  12. An optical fiber Bragg grating and piezoelectric ceramic voltage sensor

    Science.gov (United States)

    Yang, Qing; He, Yanxiao; Sun, Shangpeng; Luo, Mandan; Han, Rui

    2017-10-01

    Voltage measurement is essential in many fields like power grids, telecommunications, metallurgy, railways, and oil production. A voltage-sensing unit, consisting of fiber Bragg gratings (FBGs) and piezoelectric ceramics, based on which an optical over-voltage sensor was proposed and fabricated in this paper. No demodulation devices like spectrometer or Fabry-Perot filter were needed to gain the voltage signal, and a relatively large sensing frequency range was acquired in this paper; thus, the cost of the sensing system is more acceptable in engineering application. The voltage to be measured was directly applied to the piezoelectric ceramic, and deformation of the ceramics and the grating would be caused because of the inverse piezoelectric effect. With a reference grating, the output light intensity change will be caused by the FBG center wavelength change; thus, the relationship between the applied voltage and the output light intensity was established. Validation of the sensor was accomplished in the frequency range from 50 Hz to 20 kHz and switching impulse waves with a test platform; good linearity of the input-output characteristic was achieved. A temperature validation test was completed, showing that the sensor maintains good temperature stability. Experimental results show that the optical over-voltage sensor can be used for voltage monitoring, and if applied with a voltage divider, the sensor can be used to measure high voltage.

  13. An optical fiber Bragg grating and piezoelectric ceramic voltage sensor.

    Science.gov (United States)

    Yang, Qing; He, Yanxiao; Sun, Shangpeng; Luo, Mandan; Han, Rui

    2017-10-01

    Voltage measurement is essential in many fields like power grids, telecommunications, metallurgy, railways, and oil production. A voltage-sensing unit, consisting of fiber Bragg gratings (FBGs) and piezoelectric ceramics, based on which an optical over-voltage sensor was proposed and fabricated in this paper. No demodulation devices like spectrometer or Fabry-Perot filter were needed to gain the voltage signal, and a relatively large sensing frequency range was acquired in this paper; thus, the cost of the sensing system is more acceptable in engineering application. The voltage to be measured was directly applied to the piezoelectric ceramic, and deformation of the ceramics and the grating would be caused because of the inverse piezoelectric effect. With a reference grating, the output light intensity change will be caused by the FBG center wavelength change; thus, the relationship between the applied voltage and the output light intensity was established. Validation of the sensor was accomplished in the frequency range from 50 Hz to 20 kHz and switching impulse waves with a test platform; good linearity of the input-output characteristic was achieved. A temperature validation test was completed, showing that the sensor maintains good temperature stability. Experimental results show that the optical over-voltage sensor can be used for voltage monitoring, and if applied with a voltage divider, the sensor can be used to measure high voltage.

  14. Whispering Gallery Mode Based Optical Fiber Sensor for Measuring Concentration of Salt Solution

    Directory of Open Access Journals (Sweden)

    Chia-Chin Chiang

    2013-01-01

    Full Text Available An optical fiber solution-concentration sensor based on whispering gallery mode (WGM is proposed in this paper. The WGM solution-concentration sensors were used to measure salt solutions, in which the concentrations ranged from 1% to 25% and the wavelength drifted from the left to the right. The experimental results showed an average sensitivity of approximately 0.372 nm/% and an R2 linearity of 0.8835. The proposed WGM sensors are of low cost, feasible for mass production, and durable for solution-concentration sensing.

  15. Bragg Grating Based Sensors in Microstructured Polymer Optical Fibers: Accelerometers and Microphones

    DEFF Research Database (Denmark)

    Stefani, Alessio

    With the growing interest towards fiber Bragg grating sensors and the growing ability in manufacturing polymer optical fibers, the development of polymer fiber Bragg sensors has catched the attention of industries with the goal of developing high performance sensors. This thesis presents...... and in microstructured fibers made of PMMA and TOPAS is reported. The gratings have been written at both 1550 nm, to take advantage of components made for telecommunications, and 850 nm, to exploit the lower loss of polymers and the fast acquisition electronics at this wavelength. A technique for writing multiplexed...

  16. Study of Optical Fiber Sensors for Cryogenic Temperature Measurements.

    Science.gov (United States)

    De Miguel-Soto, Veronica; Leandro, Daniel; Lopez-Aldaba, Aitor; Beato-López, Juan Jesus; Pérez-Landazábal, José Ignacio; Auguste, Jean-Louis; Jamier, Raphael; Roy, Philippe; Lopez-Amo, Manuel

    2017-11-30

    In this work, the performance of five different fiber optic sensors at cryogenic temperatures has been analyzed. A photonic crystal fiber Fabry-Pérot interferometer, two Sagnac interferometers, a commercial fiber Bragg grating (FBG), and a π-phase shifted fiber Bragg grating interrogated in a random distributed feedback fiber laser have been studied. Their sensitivities and resolutions as sensors for cryogenic temperatures have been compared regarding their advantages and disadvantages. Additionally, the results have been compared with the given by a commercial optical backscatter reflectometer that allowed for distributed temperature measurements of a single mode fiber.

  17. Optical fiber pressure sensor based on fiber Bragg grating

    Science.gov (United States)

    Song, Dongcao

    In oil field, it is important to measure the high pressure and temperature for down-hole oil exploration and well-logging, the available traditional electronic sensor is challenged due to the harsh, flammable environment. Recently, applications based on fiber Bragg grating (FBG) sensor in the oil industry have become a popular research because of its distinguishing advantages such as electrically passive operation, immunity to electromagnetic interference, high resolution, insensitivity to optical power fluctuation etc. This thesis is divided into two main sections. In the first section, the design of high pressure sensor based on FBG is described. Several sensing elements based on FBG for high pressure measurements have been proposed, for example bulk-modulus or free elastic modulus. But the structure of bulk-modulus and free elastic modulus is relatively complex and not easy to fabricate. In addition, the pressure sensitivity is not high and the repeatability of the structure has not been investigated. In this thesis, a novel host material of carbon fiber laminated composite (CFLC) for high pressure sensing is proposed. The mechanical characteristics including principal moduli in three directions and the shape repeatability are investigated. Because of it's Young's modulus in one direction and anisotropic characteristics, the pressure sensor made by CFLC has excellent sensitivity. This said structure can be used in very high pressure measurement due to carbon fiber composite's excellent shape repetition even under high pressure. The experimental results show high pressure sensitivity of 0.101nm/MPa and high pressure measurement up to 70MPa. A pressure sensor based on CFLC and FBG with temperature compensation has been designed. In the second section, the design of low pressure sensor based on FBG is demonstrated. Due to the trade off between measurement range and sensitivity, a sensor for lower pressure range needs more sensitivity. A novel material of carbon

  18. Study of Optical Fiber Sensors for Cryogenic Temperature Measurements

    Directory of Open Access Journals (Sweden)

    Veronica De Miguel-Soto

    2017-11-01

    Full Text Available In this work, the performance of five different fiber optic sensors at cryogenic temperatures has been analyzed. A photonic crystal fiber Fabry-Pérot interferometer, two Sagnac interferometers, a commercial fiber Bragg grating (FBG, and a π-phase shifted fiber Bragg grating interrogated in a random distributed feedback fiber laser have been studied. Their sensitivities and resolutions as sensors for cryogenic temperatures have been compared regarding their advantages and disadvantages. Additionally, the results have been compared with the given by a commercial optical backscatter reflectometer that allowed for distributed temperature measurements of a single mode fiber.

  19. Adaptable Optical Fiber Displacement-Curvature Sensor Based on a Modal Michelson Interferometer with a Tapered Single Mode Fiber.

    Science.gov (United States)

    Salceda-Delgado, G; Martinez-Rios, A; Selvas-Aguilar, R; Álvarez-Tamayo, R I; Castillo-Guzman, A; Ibarra-Escamilla, B; Durán-Ramírez, V M; Enriquez-Gomez, L F

    2017-06-02

    A compact, highly sensitive optical fiber displacement and curvature radius sensor is presented. The device consists of an adiabatic bi-conical fused fiber taper spliced to a single-mode fiber (SMF) segment with a flat face end. The bi-conical taper structure acts as a modal coupling device between core and cladding modes for the SMF segment. When the bi-conical taper is bent by an axial displacement, the symmetrical bi-conical shape of the tapered structure is stressed, causing a change in the refractive index profile which becomes asymmetric. As a result, the taper adiabaticity is lost, and interference between modes appears. As the bending increases, a small change in the fringe visibility and a wavelength shift on the periodical reflection spectrum of the in-fiber interferometer is produced. The displacement sensitivity and the spectral periodicity of the device can be adjusted by the proper selection of the SMF length. Sensitivities from around 1.93 to 3.4 nm/mm were obtained for SMF length between 7.5 and 12.5 cm. Both sensor interrogations, wavelength shift and visibility contrast, can be used to measure displacement and curvature radius magnitudes.

  20. Optical Fiber-Tip Sensors Based on In-Situ µ-Printed Polymer Suspended-Microbeams.

    Science.gov (United States)

    Yao, Mian; Ouyang, Xia; Wu, Jushuai; Zhang, A Ping; Tam, Hwa-Yaw; Wai, P K A

    2018-06-05

    Miniature optical fiber-tip sensors based on directly µ-printed polymer suspended-microbeams are presented. With an in-house optical 3D μ-printing technology, SU-8 suspended-microbeams are fabricated in situ to form Fabry⁻Pérot (FP) micro-interferometers on the end face of standard single-mode optical fiber. Optical reflection spectra of the fabricated FP micro-interferometers are measured and fast Fourier transform is applied to analyze the cavity of micro-interferometers. The applications of the optical fiber-tip sensors for refractive index (RI) sensing and pressure sensing, which showed 917.3 nm/RIU to RI change and 4.29 nm/MPa to pressure change, respectively, are demonstrated in the experiments. The sensors and their optical µ-printing method unveil a new strategy to integrate complicated microcomponents on optical fibers toward 'lab-on-fiber' devices and applications.

  1. Plasmonic Sensors Based on Doubly-Deposited Tapered Optical Fibers

    Directory of Open Access Journals (Sweden)

    Agustín González-Cano

    2014-03-01

    Full Text Available A review of the surface plasmon resonance (SPR transducers based on tapered fibers that have been developed in the last years is presented. The devices have proved their good performance (specifically, in terms of sensitivity and their versatility and they are a very good option to be considered as basis for any kind of chemical and biological sensor. The technology has now reached its maturity and here we summarize some of the characteristics of the devices produced.

  2. Optical fiber sensors for image formation in radiodiagnostic - preliminary essays

    International Nuclear Information System (INIS)

    Carvalho, Cesar C. de; Werneck, Marcelo M.

    1998-01-01

    This work describes preliminary experiments that will bring subsidies to analyze the capability to implement a system able to capture radiological images with new sensor system, comprised by FOs scanning process and I-CCD camera. These experiments have the main objective to analyze the optical response from FOs bundle, with several typos of scintillators associated with them, when it is submitted to medical x-rays exposition. (author)

  3. Quasi-D-shaped optical fiber plasmonic refractive index sensor

    Science.gov (United States)

    An, Guowen; Li, Shuguang; Wang, Haiyang; Zhang, Xuenan; Yan, Xin

    2018-03-01

    A quasi-D-shaped photonic crystal fiber plasmonic sensor with a rectangular lattice is proposed by using Au as a plasmonic layer and graphene to enhance the sensing performance. By moving the core to the edge of the fiber, a shorter polishing depth is achieved, which makes the fiber proposed have a greater mechanical strength than other common D-shaped fibers. Benefiting from the natural advantage of the rectangular lattice, the dual sensing channels make the proposed sensor show a maximum wavelength interrogation sensitivity of 3877 nm/RIU with the dynamic refractive index range from 1.33 to 1.42 and a maximum amplitude sensitivity of 1236 RIU-1 with the analyte RI = 1.41 in the visible region. The corresponding resolutions are 2.58 × 10-5 and 8.1 × 10-6 with the methods of the wavelength interrogation method and amplitude- or phase-based method. These advantages make the proposed sensor a competitive candidate for biosensing in the field of refractive index detection, such as water quality analysis, clinical medicine detection, and pharmaceutical testing.

  4. In-Situ Three-Dimensional Shape Rendering from Strain Values Obtained Through Optical Fiber Sensors

    Science.gov (United States)

    Chan, Hon Man (Inventor); Parker, Jr., Allen R. (Inventor)

    2015-01-01

    A method and system for rendering the shape of a multi-core optical fiber or multi-fiber bundle in three-dimensional space in real time based on measured fiber strain data. Three optical fiber cores arc arranged in parallel at 120.degree. intervals about a central axis. A series of longitudinally co-located strain sensor triplets, typically fiber Bragg gratings, are positioned along the length of each fiber at known intervals. A tunable laser interrogates the sensors to detect strain on the fiber cores. Software determines the strain magnitude (.DELTA.L/L) for each fiber at a given triplet, but then applies beam theory to calculate curvature, beading angle and torsion of the fiber bundle, and from there it determines the shape of the fiber in s Cartesian coordinate system by solving a series of ordinary differential equations expanded from the Frenet-Serrat equations. This approach eliminates the need for computationally time-intensive curve-tilting and allows the three-dimensional shape of the optical fiber assembly to be displayed in real-time.

  5. Integration of Curved D-Type Optical Fiber Sensor with Microfluidic Chip.

    Science.gov (United States)

    Sun, Yung-Shin; Li, Chang-Jyun; Hsu, Jin-Cherng

    2016-12-30

    A curved D-type optical fiber sensor (OFS) combined with a microfluidic chip is proposed. This OFS, based on surface plasmon resonance (SPR) of the Kretchmann's configuration, is applied as a biosensor to measure the concentrations of different bio-liquids such as ethanol, methanol, and glucose solutions. The SPR phenomenon is attained by using the optical fiber to guide the light source to reach the side-polished, gold-coated region. Integrating this OFS with a polymethylmethacrylate (PMMA)-based microfluidic chip, the SPR spectra for liquids with different refractive indices are recorded. Experimentally, the sensitivity of the current biosensor was calculated to be in the order of 10 -5 RIU. This microfluidic chip-integrated OFS could be valuable for monitoring subtle changes in biological samples such as blood sugar, allergen, and biomolecular interactions.

  6. Integration of Curved D-Type Optical Fiber Sensor with Microfluidic Chip

    Directory of Open Access Journals (Sweden)

    Yung-Shin Sun

    2016-12-01

    Full Text Available A curved D-type optical fiber sensor (OFS combined with a microfluidic chip is proposed. This OFS, based on surface plasmon resonance (SPR of the Kretchmann’s configuration, is applied as a biosensor to measure the concentrations of different bio-liquids such as ethanol, methanol, and glucose solutions. The SPR phenomenon is attained by using the optical fiber to guide the light source to reach the side-polished, gold-coated region. Integrating this OFS with a polymethylmethacrylate (PMMA-based microfluidic chip, the SPR spectra for liquids with different refractive indices are recorded. Experimentally, the sensitivity of the current biosensor was calculated to be in the order of 10−5 RIU. This microfluidic chip-integrated OFS could be valuable for monitoring subtle changes in biological samples such as blood sugar, allergen, and biomolecular interactions.

  7. The phase interrogation method for optical fiber sensor by analyzing the fork interference pattern

    Science.gov (United States)

    Lv, Riqing; Qiu, Liqiang; Hu, Haifeng; Meng, Lu; Zhang, Yong

    2018-02-01

    The phase interrogation method for optical fiber sensor is proposed based on the fork interference pattern between the orbital angular momentum beam and plane wave. The variation of interference pattern with phase difference between the two light beams is investigated to realize the phase interrogation. By employing principal component analysis method, the features of the interference pattern can be extracted. Moreover, the experimental system is designed to verify the theoretical analysis, as well as feasibility of phase interrogation. In this work, the Mach-Zehnder interferometer was employed to convert the strain applied on sensing fiber to the phase difference between the reference and measuring paths. This interrogation method is also applicable for the measurements of other physical parameters, which can produce the phase delay in optical fiber. The performance of the system can be further improved by employing highlysensitive materials and fiber structures.

  8. Highly Sensitive and Wide-Dynamic-Range Multichannel Optical-Fiber pH Sensor Based on PWM Technique

    Science.gov (United States)

    Khan, Md. Rajibur Rahaman; Kang, Shin-Won

    2016-01-01

    In this study, we propose a highly sensitive multichannel pH sensor that is based on an optical-fiber pulse width modulation (PWM) technique. According to the optical-fiber PWM method, the received sensing signal’s pulse width changes when the optical-fiber pH sensing-element of the array comes into contact with pH buffer solutions. The proposed optical-fiber PWM pH-sensing system offers a linear sensing response over a wide range of pH values from 2 to 12, with a high pH-sensing ability. The sensitivity of the proposed pH sensor is 0.46 µs/pH, and the correlation coefficient R2 is approximately 0.997. Additional advantages of the proposed optical-fiber PWM pH sensor include a short/fast response-time of about 8 s, good reproducibility properties with a relative standard deviation (RSD) of about 0.019, easy fabrication, low cost, small size, reusability of the optical-fiber sensing-element, and the capability of remote sensing. Finally, the performance of the proposed PWM pH sensor was compared with that of potentiometric, optical-fiber modal interferometer, and optical-fiber Fabry–Perot interferometer pH sensors with respect to dynamic range width, linearity as well as response and recovery times. We observed that the proposed sensing systems have better sensing abilities than the above-mentioned pH sensors. PMID:27834865

  9. Fiber optic vibration sensor using bifurcated plastic optical fiber

    Science.gov (United States)

    Abdullah, M.; Bidin, N.; Yasin, M.

    2016-11-01

    An extrinsic fiber optic vibration sensor is demonstrated for a fiber optic displacement sensor based on a bundled multimode fiber to measure a vibration frequency ranging from 100 until 3000 Hz. The front slope has a sensitivity of 0.1938mV/mm and linearity of 99.7% within a measurement range between 0.15-3.00 mm. By placing the diaphragm of the concave load-speaker within the linear range from the probe, the frequency of the vibration can be measured with error percentage of less than 1.54%. The graph of input against output frequency for low, medium and high frequency range show very high linearity up to 99%. Slope for low, medium, and high frequency range are calculated as 1.0026, 0.9934, and 1.0007 respectively. Simplicity, long term stability, low power consumption, wide dynamic and frequency ranges, noise reduction, ruggedness, linearity and light weight make it promising alternative to other well-establish methods for vibration frequency measurement.

  10. Experimental results for characterization of a tapered plastic optical fiber sensor based on SPR

    Science.gov (United States)

    Cennamo, N.; Galatus, R.; Zeni, L.

    2015-05-01

    The experimental results obtained with two different Plastic Optical Fiber (POF) geometries, tapered and not-tapered, for a sensor based on Surface Plasmon Resonance (SPR) are presented. SPR is used for determining the refractive index variations at the interface between a gold layer and a dielectric medium (aqueous medium). In this work SPR sensors in POF configurations, useful for bio-sensing applications, have been realized for the optimization of the sensitivity and experimentally tested. The results show as the sensitivity increases with the tapered POF configuration, when the refractive index of aqueous medium increases.

  11. A loss-based, magnetic field sensor implemented in a ferrofluid infiltrated microstructured polymer optical fiber

    International Nuclear Information System (INIS)

    Candiani, A.; Argyros, A.; Leon-Saval, S. G.; Lwin, R.; Selleri, S.; Pissadakis, S.

    2014-01-01

    We report an in-fiber magnetic field sensor based on magneto-driven optical loss effects, while being implemented in a ferrofluid infiltrated microstructured polymer optical fiber. We demonstrate that magnetic field flux changes up to 2000 gauss can be detected when the magnetic field is applied perpendicular to the fiber axis. In addition, the sensor exhibits high polarization sensitivity for the interrogated wavelengths, providing the possibility of both field flux and direction measurements. The underlying physical and guidance mechanisms of this sensing transduction are further investigated using spectrophotometric, light scattering measurements, and numerical simulations, suggesting photonic Hall effect as the dominant physical, transducing mechanism

  12. Optical fiber sensor for the detection of laser-generated ultrasound in arterial tissues

    Science.gov (United States)

    Beard, Paul C.; Mills, Timothy N.

    1995-02-01

    Theoretical and experimental aspects of an extrinsic Fabry-Perot optical fiber ultrasound sensor for use in a photoacoustic-guided laser angioplasty system are described. The sensor has been characterized using laser generated thermoelastic waves as a source of wideband ultrasound. A system sensitivity of 25 mV/MPa and an acoustic noise floor of 2 Pa/Hz1/2 are reported using a transparent polymer film as the sensing element. The system demonstrates the required bandwidth for sensing thermoelastic waves containing frequency components up to 20 MHz.

  13. Temperature and strain measurements in concrete using micro-structure optical fiber sensors

    Energy Technology Data Exchange (ETDEWEB)

    Areias, Lou [EURIDICE/SCK - CEN, Mol (Belgium); Vrije Univ. Brussels (Belgium); Geernaert, Thomas; Sulejmani, Sanne [Vrije Univ. Brussels (Belgium); and others

    2015-07-01

    A recent test carried out to evaluate the construction feasibility of the Belgian supercontainer concept incorporated several types of state-of-the-art sensors and innovative monitoring techniques, including the use of different types of optical fiber sensors. One of these is a relatively new type of sensor developed by the Brussels Photonics Team (B-PHOT) of the Vrije Universiteit Brussel. The sensor uses highly birefringent microstructured optical fibers equipped with fiber Bragg gratings (MOFBGs) sensors. They were embedded in a carbon-fiber reinforced composite plate to provide protection against the concrete's highly alkaline environment, facilitate installation in the concrete mould and allow the transfer of strain onto the fiber. The double reflection spectrum of the MOFBGs allows monitoring strain and temperature simultaneously. This paper presents results of temperature and strain measurements obtained with MOFBG sensors during a {sup 1}/{sub 2}-scale test performed in 2013. The results compare well with similar measurements obtained using conventional thermocouples and vibrating wire strain gauges.

  14. Towards a Uniform Metrological Assessment of Grating-Based Optical Fiber Sensors: From Refractometers to Biosensors.

    Science.gov (United States)

    Chiavaioli, Francesco; Gouveia, Carlos A J; Jorge, Pedro A S; Baldini, Francesco

    2017-06-21

    A metrological assessment of grating-based optical fiber sensors is proposed with the aim of providing an objective evaluation of the performance of this sensor category. Attention was focused on the most common parameters, used to describe the performance of both optical refractometers and biosensors, which encompassed sensitivity, with a distinction between volume or bulk sensitivity and surface sensitivity, resolution, response time, limit of detection, specificity (or selectivity), reusability (or regenerability) and some other parameters of generic interest, such as measurement uncertainty, accuracy, precision, stability, drift, repeatability and reproducibility. Clearly, the concepts discussed here can also be applied to any resonance-based sensor, thus providing the basis for an easier and direct performance comparison of a great number of sensors published in the literature up to now. In addition, common mistakes present in the literature made for the evaluation of sensor performance are highlighted, and lastly a uniform performance assessment is discussed and provided. Finally, some design strategies will be proposed to develop a grating-based optical fiber sensing scheme with improved performance.

  15. Environmental sensing with optical fiber sensors processed with focused ion beam and atomic layer deposition

    Science.gov (United States)

    Flores, Raquel; Janeiro, Ricardo; Dahlem, Marcus; Viegas, Jaime

    2015-03-01

    We report an optical fiber chemical sensor based on a focused ion beam processed optical fiber. The demonstrated sensor is based on a cavity formed onto a standard 1550 nm single-mode fiber by either chemical etching, focused ion beam milling (FIB) or femtosecond laser ablation, on which side channels are drilled by either ion beam milling or femtosecond laser irradiation. The encapsulation of the cavity is achieved by optimized fusion splicing onto a standard single or multimode fiber. The empty cavity can be used as semi-curved Fabry-Pérot resonator for gas or liquid sensing. Increased reflectivity of the formed cavity mirrors can be achieved with atomic layer deposition (ALD) of alternating metal oxides. For chemical selective optical sensors, we demonstrate the same FIB-formed cavity concept, but filled with different materials, such as polydimethylsiloxane (PDMS), poly(methyl methacrylate) (PMMA) which show selective swelling when immersed in different solvents. Finally, a reducing agent sensor based on a FIB formed cavity partially sealed by fusion splicing and coated with a thin ZnO layer by ALD is presented and the results discussed. Sensor interrogation is achieved with spectral or multi-channel intensity measurements.

  16. Radiation hardening of optical fibers and fiber sensors for space applications: recent advances

    Science.gov (United States)

    Girard, S.; Ouerdane, Y.; Pinsard, E.; Laurent, A.; Ladaci, A.; Robin, T.; Cadier, B.; Mescia, L.; Boukenter, A.

    2017-11-01

    In these ICSO proceedings, we review recent advances from our group concerning the radiation hardening of optical fiber and fiber-based sensors for space applications and compare their benefits to state-of-the-art results. We focus on the various approaches we developed to enhance the radiation tolerance of two classes of optical fibers doped with rare-earths: the erbium (Er)-doped ones and the ytterbium/erbium (Er/Yb)-doped ones. As a first approach, we work at the component level, optimizing the fiber structure and composition to reduce their intrinsically high radiation sensitivities. For the Erbium-doped fibers, this has been achieved using a new structure for the fiber that is called Hole-Assisted Carbon Coated (HACC) optical fibers whereas for the Er/Ybdoped optical fibers, their hardening was successfully achieved adding to the fiber, the Cerium element, that prevents the formation of the radiation-induced point defects responsible for the radiation induced attenuation in the infrared part of the spectrum. These fibers are used as part of more complex systems like amplifiers (Erbium-doped Fiber Amplifier, EDFA or Yb-EDFA) or source (Erbium-doped Fiber Source, EDFS or Yb- EDFS), we discuss the impact of using radiation-hardened fibers on the system radiation vulnerability and demonstrate the resistance of these systems to radiation constraints associated with today and future space missions. Finally, we will discuss another radiation hardening approach build in our group and based on a hardening-by-system strategy in which the amplifier is optimized during its elaboration for its future mission considering the radiation effects and not in-lab.

  17. Hysteresis compensation technique applied to polymer optical fiber curvature sensor for lower limb exoskeletons

    Science.gov (United States)

    Gomes Leal-Junior, Arnaldo; Frizera-Neto, Anselmo; José Pontes, Maria; Rodrigues Botelho, Thomaz

    2017-12-01

    Polymer optical fiber (POF) curvature sensors present some advantages over conventional techniques for angle measurements, such as their light weight, compactness and immunity to electromagnetic fields. However, high hysteresis can occur in POF curvature sensors due to the polymer viscoelastic response. In order to overcome this limitation, this paper shows how the hysteresis sensor can be compensated by a calibration equation relating the measured output signal to the sensor’s angular velocity. The proposed method is validated using an exoskeleton with an active joint on the knee for flexion and extension rehabilitation exercises. The results show a decrease in sensor hysteresis and a decrease by more than two times in the error between the POF sensor and the potentiometer, which is employed for the angle measurement of the exoskeleton knee joint.

  18. An Optical Fiber Bundle Sensor for Tip Clearance and Tip Timing Measurements in a Turbine Rig

    Directory of Open Access Journals (Sweden)

    María Asunción Illarramendi

    2013-06-01

    Full Text Available When it comes to measuring blade-tip clearance or blade-tip timing in turbines, reflective intensity-modulated optical fiber sensors overcome several traditional limitations of capacitive, inductive or discharging probe sensors. This paper presents the signals and results corresponding to the third stage of a multistage turbine rig, obtained from a transonic wind-tunnel test. The probe is based on a trifurcated bundle of optical fibers that is mounted on the turbine casing. To eliminate the influence of light source intensity variations and blade surface reflectivity, the sensing principle is based on the quotient of the voltages obtained from the two receiving bundle legs. A discrepancy lower than 3% with respect to a commercial sensor was observed in tip clearance measurements. Regarding tip timing measurements, the travel wave spectrum was obtained, which provides the average vibration amplitude for all blades at a particular nodal diameter. With this approach, both blade-tip timing and tip clearance measurements can be carried out simultaneously. The results obtained on the test turbine rig demonstrate the suitability and reliability of the type of sensor used, and suggest the possibility of performing these measurements in real turbines under real working conditions.

  19. Glucose Sensor Using U-Shaped Optical Fiber Probe with Gold Nanoparticles and Glucose Oxidase.

    Science.gov (United States)

    Chen, Kuan-Chieh; Li, Yu-Le; Wu, Chao-Wei; Chiang, Chia-Chin

    2018-04-16

    In this study, we proposed a U-shaped optical fiber probe fabricated using a flame heating method. The probe was packaged in glass tube to reduce human factors during experimental testing of the probe as a glucose sensor. The U-shaped fiber probe was found to have high sensitivity in detecting the very small molecule. When the sensor was dipped in solutions with different refractive indexes, its wavelength or transmission loss changed. We used electrostatic self-assembly to bond gold nanoparticles and glucose oxidase (GOD) onto the sensor’s surface. The results over five cycles of the experiment showed that, as the glucose concentration increased, the refractive index of the sensor decreased and its spectrum wavelength shifted. The best wavelength sensitivity was 2.899 nm/%, and the linearity was 0.9771. The best transmission loss sensitivity was 5.101 dB/%, and the linearity was 0.9734. Therefore, the proposed U-shaped optical fiber probe with gold nanoparticles and GOD has good potential for use as a blood sugar sensor in the future.

  20. Casing Pipe Damage Detection with Optical Fiber Sensors: A Case Study in Oil Well Constructions

    Directory of Open Access Journals (Sweden)

    Zhi Zhou

    2010-01-01

    Full Text Available Casing pipes in oil well constructions may suddenly buckle inward as their inside and outside hydrostatic pressure difference increases. For the safety of construction workers and the steady development of oil industries, it is critically important to measure the stress state of a casing pipe. This study develops a rugged, real-time monitoring, and warning system that combines the distributed Brillouin Scattering Time Domain Reflectometry (BOTDR and the discrete fiber Bragg grating (FBG measurement. The BOTDR optical fiber sensors were embedded with no optical fiber splice joints in a fiber-reinforced polymer (FRP rebar and the FBG sensors were wrapped in epoxy resins and glass clothes, both installed during the segmental construction of casing pipes. In situ tests indicate that the proposed sensing system and installation technique can survive the downhole driving process of casing pipes, withstand a harsh service environment, and remain intact with the casing pipes for compatible strain measurements. The relative error of the measured strains between the distributed and discrete sensors is less than 12%. The FBG sensors successfully measured the maximum horizontal principal stress with a relative error of 6.7% in comparison with a cross multipole array acoustic instrument.

  1. Micro-controller based air pressure monitoring instrumentation system using optical fibers as sensor

    Science.gov (United States)

    Hazarika, D.; Pegu, D. S.

    2013-03-01

    This paper describes a micro-controller based instrumentation system to monitor air pressure using optical fiber sensors. The principle of macrobending is used to develop the sensor system. The instrumentation system consists of a laser source, a beam splitter, two multi mode optical fibers, two Light Dependent Resistance (LDR) based timer circuits and a AT89S8252 micro-controller. The beam splitter is used to divide the laser beam into two parts and then these two beams are launched into two multi mode fibers. One of the multi mode fibers is used as the sensor fiber and the other one is used as the reference fiber. The use of the reference fiber is to eliminate the environmental effects while measuring the air pressure magnitude. The laser beams from the sensor and reference fibers are applied to two identical LDR based timer circuits. The LDR based timer circuits are interfaced to a micro-controller through its counter pins. The micro-controller samples the frequencies of the timer circuits using its counter-0 and counter-1 and the counter values are then processed to provide the measure of air pressure magnitude.

  2. Temperature measurement of geothermal wells by optical fiber sensor; Hikari fiber sensor wo mochiita chinetsusei no ondo bunpu keisoku

    Energy Technology Data Exchange (ETDEWEB)

    Matsushima, N; Sakaguchi, K [Geological Survey of Japan, Tsukuba (Japan)

    1996-10-01

    Experiments of temperature measurement were conducted in high temperature and high pressure geothermal wells using optical fiber sensor. A temperature measurement system using optical fiber sensor was applied to geothermal wells. Working availability was confirmed under the condition up to the depth of 1,750 m and the temperature of 240 centigrade. Observed values agreed well with those observed by the conventional temperature logging. Durability of the optical fiber sensor was also sufficient. The maximum standard deviations of measured values were 1.3 centigrade at the depth of 1,750 m at 195 centigrade for the loop-type sensor, and 3.7 centigrade at the depth of 365 m at about 200 centigrade for the single-end sensor. Although the accuracy was inferior to the conventional measurement using a thermo couple, it was enough to be applied to usual temperature logging. Furthermore, for this system, the temperature profile in the whole well can be monitored, simultaneously. Through the experiments, the detailed successive change of temperature profile accompanied with the water injection can be clearly illustrated. 3 refs., 7 figs.

  3. Polymer optical fiber compound parabolic concentrator tip for enhanced coupling efficiency for fluorescence based glucose sensors

    DEFF Research Database (Denmark)

    Hassan, Hafeez Ul; Nielsen, Kristian; Aasmul, Søren

    2015-01-01

    We demonstrate that the light excitation and capturing efficiency of fluorescence based fiber-optical sensors can be significantly increased by using a CPC (Compound Parabolic Concentrator) tip instead of the standard plane-cut tip. We use Zemax modelling to find the optimum CPC tip profile...... and fiber length of a polymer optical fiber diabetes sensor for continuous monitoring of glucose levels. We experimentally verify the improved performance of the CPC tipped sensor and the predicted production tolerances. Due to physical size requirements when the sensor has to be inserted into the body...... a non-optimal fiber length of 35 mm is chosen. For this length an average improvement in efficiency of a factor of 1.7 is experimentally demonstrated and critically compared to the predicted ideal factor of 3 in terms of parameters that should be improved through production optimization....

  4. Polymer optical fiber compound parabolic concentrator tip for enhanced coupling efficiency for fluorescence based glucose sensors.

    Science.gov (United States)

    Hassan, Hafeez Ul; Nielsen, Kristian; Aasmul, Soren; Bang, Ole

    2015-12-01

    We demonstrate that the light excitation and capturing efficiency of fluorescence based fiber-optical sensors can be significantly increased by using a CPC (Compound Parabolic Concentrator) tip instead of the standard plane-cut tip. We use Zemax modelling to find the optimum CPC tip profile and fiber length of a polymer optical fiber diabetes sensor for continuous monitoring of glucose levels. We experimentally verify the improved performance of the CPC tipped sensor and the predicted production tolerances. Due to physical size requirements when the sensor has to be inserted into the body a non-optimal fiber length of 35 mm is chosen. For this length an average improvement in efficiency of a factor of 1.7 is experimentally demonstrated and critically compared to the predicted ideal factor of 3 in terms of parameters that should be improved through production optimization.

  5. Surface plasmon resonance based optical fiber riboflavin sensor by using molecularly imprinted gel

    Science.gov (United States)

    Verma, Roli; Gupta, Banshi D.

    2013-05-01

    We report the fabrication and characterization of surface plasmon resonance (SPR) based optical fiber riboflavin/vitamin B2 sensor using combination of colloidal crystal templating and molecularly imprinted gel. The sensor works on spectral interrogation method. The operating range of the sensor lies from 0 μg/ml to 320 μg/ml, the suitable amount of intakes of riboflavin recommended for different age group. The SPR spectra show blue shift with increasing concentration of riboflavin, which is due to the interaction of riboflavin molecule over specific binding sites caused by molecular imprinting. The present sensor has many advantageous features such as fast response, small probe size, low cost and can be used for remote/online monitoring.

  6. Distributed fluorescent optical fiber proximity sensor: Towards a proof of concept

    Science.gov (United States)

    Gălătuș, Ramona; Faragó, Paul; Miluski, Piotr; Valles, Juan-Antonio

    2018-06-01

    Fluorescent fibers are optical fibers which emit light as a response to an incident phenomenon, usually an incident light. Operation depends on the doping dyes, which determine specific fluorescence and optical characteristics useful in the development of optical sensors. In this work we propose a low-cost distributed proximity sensor implemented using a red fluorescent fiber, to provide a security option for a surface plasmon resonance system. Operation of the proposed sensor relies on having the incident illumination intensity varied by the presence or absence of an obstacle in the vicinity of the sensing element. This will influence the radiated fluorescence accordingly. The proposed setup for the implementation of the optical proximity sensor assumes having a high brightness LED deployed for axial fiber illumination and a blue LED for side illumination. Electronic processing then accounts for gain and digitization. Measurement results of the prototype validate the proposed concept.

  7. Alternative technique for biodiesel quality control using an optical fiber long-period grating sensor

    International Nuclear Information System (INIS)

    Falate, Rosane; Nike, Karen; Costa Neto, Pedro Ramos da; Cacao Junior, Eduardo; Muller, Marcia; Kalinowski, Hypolito Jose; Fabris, Jose Luis

    2007-01-01

    We report the use of an optical fiber sensor to measure the soybean oil concentration in samples obtained from the mixture of pure biodiesel and commercial soybean oil. The operation of the device is based on the long-period grating sensitivity to the surrounding medium refractive index, which leads to measurable modifications in the grating transmission spectrum. The proposed analysis method results in errors in the oil concentration of 0.4% and 2.6% for pure biodiesel and commercial soybean oil, respectively. Techniques of total glycerol, dynamic viscosity, density, and hydrogen nuclear magnetic resonance spectroscopy were also employed to validate the proposed method. (author)

  8. Tiny optical fiber temperature sensor based on temperature-dependent refractive index of zinc telluride film

    Science.gov (United States)

    Bian, Qiang; Song, Zhangqi; Song, Dongyu; Zhang, Xueliang; Li, Bingsheng; Yu, Yang; Chen, Yuzhong

    2018-03-01

    The temperature-dependent refractive index of zinc telluride film can be used to develop a tiny, low cost and film-coated optical fiber temperature sensor. Pulse reference-based compensation technique is used to largely reduce the background noise which makes it possible to detect the minor reflectivity change of the film in different temperatures. The temperature sensitivity is 0.0034dB/° and the background noise is measured to be 0.0005dB, so the resolution can achieve 0.2°.

  9. Fuel level sensor based on polymer optical fiber Bragg gratings for aircraft applications

    DEFF Research Database (Denmark)

    Marques, C. A. F.; Pospori, A.; Sáez-Rodríguez, D.

    2016-01-01

    on capacitive, ultrasonic and electric techniques, however they suffer from intrinsic safety concerns in explosive environments combined with issues relating to reliability and maintainability. In the last few years, optical fiber liquid level sensors (OFLLSs) have been reported to be safe and reliable...... in diaphragms is investigated in detail. The mPOFBGs are embedded in two different types of diaphragms and their performance is investigated with aviation fuel for the first time, in contrast to our previous works, where water was used. Our new system exhibits a high performance when compared with other...

  10. Alternative technique for biodiesel quality control using an optical fiber long-period grating sensor

    Energy Technology Data Exchange (ETDEWEB)

    Falate, Rosane [Universidade Estadual de Ponta Grossa, PR (Brazil). Dept. de Informatica; Nike, Karen; Costa Neto, Pedro Ramos da [Universidade Tecnologica Federal do Parana, Curitiba (Brazil). Dept. de Quimica; Cacao Junior, Eduardo; Muller, Marcia; Kalinowski, Hypolito Jose; Fabris, Jose Luis [Universidade Tecnologica Federal do Parana, Curitiba (Brazil). Dept. de Fisica]. E-mail: fabris@utfpr.edu.br

    2007-07-01

    We report the use of an optical fiber sensor to measure the soybean oil concentration in samples obtained from the mixture of pure biodiesel and commercial soybean oil. The operation of the device is based on the long-period grating sensitivity to the surrounding medium refractive index, which leads to measurable modifications in the grating transmission spectrum. The proposed analysis method results in errors in the oil concentration of 0.4% and 2.6% for pure biodiesel and commercial soybean oil, respectively. Techniques of total glycerol, dynamic viscosity, density, and hydrogen nuclear magnetic resonance spectroscopy were also employed to validate the proposed method. (author)

  11. Optical fiber biocompatible sensors for monitoring selective treatment of tumors via thermal ablation

    Science.gov (United States)

    Tosi, Daniele; Poeggel, Sven; Dinesh, Duraibabu B.; Macchi, Edoardo G.; Gallati, Mario; Braschi, Giovanni; Leen, Gabriel; Lewis, Elfed

    2015-09-01

    Thermal ablation (TA) is an interventional procedure for selective treatment of tumors, that results in low-invasive outpatient care. The lack of real-time control of TA is one of its main weaknesses. Miniature and biocompatible optical fiber sensors are applied to achieve a dense, multi-parameter monitoring, that can substantially improve the control of TA. Ex vivo measurements are reported performed on porcine liver tissue, to reproduce radiofrequency ablation of hepatocellular carcinoma. Our measurement campaign has a two-fold focus: (1) dual pressure-temperature measurement with a single probe; (2) distributed thermal measurement to estimate point-by-point cells mortality.

  12. Bending Characteristics Change of Long-Period fiber Grating due to Co-doping of Boron for Optical fiber Sensors

    International Nuclear Information System (INIS)

    Moon, Dae Seung; Chung, Young Joo

    2005-01-01

    In long-period fiber grating (LPFG) to be made up optical fiber sensors, resonance coupling occurs between the forward-propagating core mode and cladding modes at the wavelength that satisfy the Phase matching condition. The resonance wavelength and the coupling strength depends strongly on the external environment like temperature, strain, and ambient index. These characteristics can be utilized for various applications as optical fiber sensors. Fabrication of optical fiber gratings is typically based on the photosensitivity effect, i.e. the permanent change of the refractive index upon irradiation of the UV beam, and therefore, fabrication of the optical fiber with high phososensitivity is an important part of the research on optical fiber gratings. In this work, we measured the effort of to-doping of boron on the index difference between the core and cladding of the optical fiber and the sensitivity of the LPFC to the temperature and bending changes. We observed that the index difference between the core and the cladding decreased by (1.69x10 -4 /SCCM) and the temperature sensitivity of the resonance wavelength shirt decreased by (0.01145nm/ .deg. C/SCCM). The dependence or the bending-induced changes or the transmission characteristics of LPFG on the tore-cladding index difference was investigated experimentally. The measurement results indicate that the bending sensitivity increases as the index difference decreases

  13. [An optical-fiber-sensor-based spectrophotometer for soil non-metallic nutrient determination].

    Science.gov (United States)

    He, Dong-xian; Hu, Juan-xiu; Lu, Shao-kun; He, Hou-yong

    2012-01-01

    In order to achieve rapid, convenient and efficient soil nutrient determination in soil testing and fertilizer recommendation, a portable optical-fiber-sensor-based spectrophotometer including immersed fiber sensor, flat field holographic concave grating, and diode array detector was developed for soil non-metallic nutrient determination. According to national standard of ultraviolet and visible spectrophotometer with JJG 178-2007, the wavelength accuracy and repeatability, baseline stability, transmittance accuracy and repeatability measured by the prototype instrument were satisfied with the national standard of III level; minimum spectral bandwidth, noise and excursion, and stray light were satisfied with the national standard of IV level. Significant linear relationships with slope of closing to 1 were found between the soil available nutrient contents including soil nitrate nitrogen, ammonia nitrogen, available phosphorus, available sulfur, available boron, and organic matter measured by the prototype instrument compared with that measured by two commercial single-beam-based and dual-beam-based spectrophotometers. No significant differences were revealed from the above comparison data. Therefore, the optical-fiber-sensor-based spectrophotometer can be used for rapid soil non-metallic nutrient determination with a high accuracy.

  14. Optical fiber radiation sensors: first in vivo measurements during orbital irradiation

    International Nuclear Information System (INIS)

    Gripp, S.; Bannach, B.; Muskalla, K.; Haesing, F.; Bueker, H.; Schmitt, G.

    1995-01-01

    Purpose: To investigate the applicability of doped optical fiber radiation sensors in clinical dosimetry. Methods: Ionizing radiation causes a dose depending discoloring in silica. When proper impurities (doping agents) are added, the radiation sensitivity may be increased to a range suited for clinical dosimetry. We performed in-vivo-measurements using a lead doped silica fiber (d TM ) in comparison to thermoluminescence detectors (TLDs). Results: The scattered radiation is easily detected with this sensor fiber. In contrast to TLDs the dose and doserate values are obtained immediately and setup errors can be recognized before irradiation is completed. The SD clearly depends on setup modifications due to the extent of disease. Other doping agents (GeP) provide better tissue equivalence and less energy dependence. Conclusions: Optical fibers are suitable for in vivo dosimetry purposes. Fiber sensors provide real time dose values, and the readout procedure is much easier compared to TLDs. These features may gain significance in quality assurance, conformal therapy, and intraoperative radiotherapy (IORT)

  15. Optical fiber sensors technology for supervision, control and protection of high power systems

    Science.gov (United States)

    Nascimento, Ivo Maciel

    The work described in this PhD Thesis focuses on the post-processing of optical fibers and their enhancement as sensing element. Since the majority of sensors presented are based in Fabry-Perot interferometers, an historical overview of this category of optical fiber sensors is firstly presented. This review considers the works published since the early years, in the beginning of the 1980s, until the middle of 2015. The incorporation of microcavities at the tip of a single mode fiber was extensively studied, particularly for the measurement of nitrogen and methane gas pressure. These cavities were fabricated using hollow core silica tubes and a hollow core photonic crystal fiber. Following a different approach, the microcavities were incorporated between two sections of single mode fiber. In this case, the low sensitivity to temperature makes these microcavities highly desirable for the measurement of strain at high temperatures. Competences in post-processing techniques such as the chemical etching and the writing of periodical structures in the fiber core by means of an excimer or a femtosecond laser were also acquired in the course of the PhD programme. One of the works consisted in the design and manufacturing of a double clad optical fiber. The refractive index of the inner cladding was higher than the one of the outer cladding and the core. Thus, light was guided in the inner cladding instead of propagating in the core. This situation was overcome by applying chemical etching, thus removing the inner cladding. The core, surrounded by air, was then able to guide light. Two different applications were found for this fiber, as a temperature sensor and as an optical refractometer. In the last, the optical phase changes with the liquid refractive index. Two different types of fiber Bragg gratings were characterized in strain and temperature. Sensing structures obtained through the phase mask technique at the tip of an optical fiber were subjected to chemical

  16. LSPR and Interferometric Sensor Modalities Combined Using a Double-Clad Optical Fiber.

    Science.gov (United States)

    Muri, Harald Ian; Bano, Andon; Hjelme, Dag Roar

    2018-01-11

    We report on characterization of an optical fiber-based multi-parameter sensor concept combining localized surface plasmon resonance (LSPR) signal and interferometric sensing using a double-clad optical fiber. The sensor consists of a micro-Fabry-Perot in the form of a hemispherical stimuli-responsive hydrogel with immobilized gold nanorods on the facet of a cleaved double-clad optical fiber. The swelling degree of the hydrogel is measured interferometrically using the single-mode inner core, while the LSPR signal is measured using the multi-mode inner cladding. The quality of the interferometric signal is comparable to previous work on hydrogel micro-Fabry-Perot sensors despite having gold nanorods immobilized in the hydrogel. We characterize the effect of hydrogel swelling and variation of bulk solution refractive index on the LSPR peak wavelength. The results show that pH-induced hydrogel swelling causes only weak redshifts of the longitudinal LSPR mode, while increased bulk refractive index using glycerol and sucrose causes large blueshifts. The redshifts are likely due to reduced plasmon coupling of the side-by-side configuration as the interparticle distance increases with increasing swelling. The blueshifts with increasing bulk refractive index are likely due to alteration of the surface electronic structure of the gold nanorods donated by the anionic polymer network and glycerol or sucrose solutions. The recombination of biotin-streptavidin on gold nanorods in hydrogel showed a 7.6 nm redshift of the longitudinal LSPR. The LSPR response of biotin-streptavidin recombination is due to the change in local refractive index (RI), which is possible to discriminate from the LSPR response due to changes in bulk RI. In spite of the large LSPR shifts due to bulk refractive index, we show, using biotin-functionalized gold nanorods binding to streptavidin, that LSPR signal from gold nanorods embedded in the anionic hydrogel can be used for label-free biosensing. These

  17. LSPR and Interferometric Sensor Modalities Combined Using a Double-Clad Optical Fiber

    Directory of Open Access Journals (Sweden)

    Harald Ian Muri

    2018-01-01

    Full Text Available We report on characterization of an optical fiber-based multi-parameter sensor concept combining localized surface plasmon resonance (LSPR signal and interferometric sensing using a double-clad optical fiber. The sensor consists of a micro-Fabry-Perot in the form of a hemispherical stimuli-responsive hydrogel with immobilized gold nanorods on the facet of a cleaved double-clad optical fiber. The swelling degree of the hydrogel is measured interferometrically using the single-mode inner core, while the LSPR signal is measured using the multi-mode inner cladding. The quality of the interferometric signal is comparable to previous work on hydrogel micro-Fabry-Perot sensors despite having gold nanorods immobilized in the hydrogel. We characterize the effect of hydrogel swelling and variation of bulk solution refractive index on the LSPR peak wavelength. The results show that pH-induced hydrogel swelling causes only weak redshifts of the longitudinal LSPR mode, while increased bulk refractive index using glycerol and sucrose causes large blueshifts. The redshifts are likely due to reduced plasmon coupling of the side-by-side configuration as the interparticle distance increases with increasing swelling. The blueshifts with increasing bulk refractive index are likely due to alteration of the surface electronic structure of the gold nanorods donated by the anionic polymer network and glycerol or sucrose solutions. The recombination of biotin-streptavidin on gold nanorods in hydrogel showed a 7.6 nm redshift of the longitudinal LSPR. The LSPR response of biotin-streptavidin recombination is due to the change in local refractive index (RI, which is possible to discriminate from the LSPR response due to changes in bulk RI. In spite of the large LSPR shifts due to bulk refractive index, we show, using biotin-functionalized gold nanorods binding to streptavidin, that LSPR signal from gold nanorods embedded in the anionic hydrogel can be used for label

  18. Noncontact Optical Fiber Sensor for Measuring the Refractive Index of Liquids

    Directory of Open Access Journals (Sweden)

    R. Selvas-Aguilar

    2016-01-01

    Full Text Available A noncontact optical fiber sensor for measuring the refractive index of transparent liquids is proposed. It operates by calculating the path of a focused laser beam at 635 nm that travels across the boundaries of a liquid sample. The optical power Fresnel reflections are detected and, subsequently, the refractive index is determined as the ratio between the traveled beam paths when the liquid is deposited versus a reference without the liquid sample. Additionally, a mathematical analysis of the geometrical case is included. The theoretical data from our sensor are in good agreement with the experimental results. The resolution achieved by the sensor is better than 10−3 RIU.

  19. Thermal and chemical treatment of polymer optical fiber Bragg grating sensors for enhanced mechanical sensitivity

    DEFF Research Database (Denmark)

    Pospori, Andreas; Marques, C. A. F.; Saez-Rodriguez, D.

    2017-01-01

    An investigation of the thermal annealing effects on the strain, stress, and force sensitivities of polymer optical fiber Bragg grating sensors is performed. We demonstrate for the first time that the fiber annealing can enhance both stress and force sensitivities of Bragg grating sensors......, with the possible cause being the molecular relaxation of the polymer when fiber is raised above the β-transition temperature. A simple, cost-effective, but well controlled method for fiber annealing is also presented in this work. In addition, the effects of chemical etching on the strain, stress, and force...... sensitivities have been investigated. Results show that fiber etching too can increase the force sensitivity, and it can also affect the strain and stress sensitivities of the Bragg grating sensors....

  20. Thermal and chemical treatment of polymer optical fiber Bragg grating sensors for enhanced mechanical sensitivity

    Science.gov (United States)

    Pospori, A.; Marques, C. A. F.; Sáez-Rodríguez, D.; Nielsen, K.; Bang, O.; Webb, D. J.

    2017-07-01

    An investigation of the thermal annealing effects on the strain, stress, and force sensitivities of polymer optical fiber Bragg grating sensors is performed. We demonstrate for the first time that the fiber annealing can enhance both stress and force sensitivities of Bragg grating sensors, with the possible cause being the molecular relaxation of the polymer when fiber is raised above the β -transition temperature. A simple, cost-effective, but well controlled method for fiber annealing is also presented in this work. In addition, the effects of chemical etching on the strain, stress, and force sensitivities have been investigated. Results show that fiber etching too can increase the force sensitivity, and it can also affect the strain and stress sensitivities of the Bragg grating sensors.

  1. A plastic optical fiber sensor for the dual sensing of temperature and oxygen

    Science.gov (United States)

    Lo, Yu-Lung; Chu, Chen-Shane

    2008-04-01

    This study presents a low-cost plastic optical fiber sensor for the dual sensing of temperature and oxygen. The sensor features a commercially available epoxy glue coated on the side-polished fiber surface for temperature sensing and a fluorinated xerogel doped with platinum tetrakis pentrafluoropheny porphine (PtTFPP) coated on the fiber end for oxygen sensing. The temperature and oxygen indicators are both excited using a UV LED light source with a wavelength of 380 nm. The luminescence emission spectra of the two indicators are well resolved and exhibit no cross-talk effects. Overall, the results indicate that the dual sensor presented in this study provides an ideal solution for the non-contact, simultaneous sensing of temperature and oxygen in general biological and medical applications.

  2. Instrumentation by distributed optical fiber sensors of a new ballastless track structure

    Science.gov (United States)

    Chapeleau, Xavier; Cottineau, Louis-Marie; Sedran, Thierry; Gueguen, Ivan; Cailliau, Joël

    2013-04-01

    While relatively expensive to build, ballastless track structures are presently seen as an attractive alternative to conventional ballast. With its service life of at least 60 years, they require little maintenance and hence they offer great availability. Other reasons for using ballastless tracks instead of ballasted tracks are the lack of suitable ballast material and the need of less noise and vibration for high-speed, in particularly. A new ballastless track structure has been designed to be circulated up to 300km/h, with a target life of 100 years. It is an interoperable way on concrete slabs that are cast-in-place and slip formed. This structure has been built and tested at the scale one in our laboratory. Indeed, ten millions cyclic loads were applied at 2.5Hz to evaluate the fatigue behaviour under selected mechanical and thermal conditions. To monitor the thermo-mechanical behavior of this new structure and to verify the numerical simulations used for its design, a lot of sensors have been embedded. In particularly, we have tested an optical fiber as distributed sensors to measure strain distribution in the railway model. This sensor can also be used to detect, localize and monitor cracks in concrete slabs. The optical fiber sensing technique ("Rayleigh technique") used in this experimentation has a centimetric spatial resolution which allows to measure complex strain profiles unlike electrical strain gauges which only give local information. Firstly, optical cables used as sensors have been successfully embedded and attached to the reinforcing steel bars in the structure. We have noted that they are resistant enough to resist concrete pouring and working activities. Secondly, strains measured by conventional strain gauges has confirmed the quality of the strain profiles measurements obtained by optical fiber sensors. Moreover, we have found a good agreement between experimental profiles measurements and those obtained by numerical simulations. Early

  3. Sensitivity optimization of ZnO clad-modified optical fiber humidity sensor by means of tuning the optical fiber waist diameter

    Science.gov (United States)

    Azad, Saeed; Sadeghi, Ebrahim; Parvizi, Roghaieh; Mazaheri, Azardokht; Yousefi, M.

    2017-05-01

    In this work, the multimode optical fiber size effects on the performances of the clad-modified fiber with ZnO nanorods relative humidity (RH) sensor were experimentally investigated. Simple and controlled chemical etching method through on line monitoring was used to prepare different fiber waist diameter with long length of 15 mm. More precisely, the competition behavior of sensor performances with varying fiber waist diameter was studied to find appropriate size of maximizing evanescent fields. The obtained results revealed that evanescent wave absorption coefficient (γ) enhanced more than 10 times compare to bare fiber at the proposed optimum fiber diameter of 28 μm. Also, high linearity and fast recovery time about 7 s was obtained at the proposed fiber waist diameter. Applicable features of the proposed sensor allow this device to be used for humidity sensing applications, especially to be applied in remote sensing technologies.

  4. Single-photon semiconductor photodiodes for distributed optical fiber sensors: state of the art and perspectives

    Science.gov (United States)

    Ripamonti, Giancarlo; Lacaita, Andrea L.

    1993-03-01

    The extreme sensitivity and time resolution of Geiger-mode avalanche photodiodes (GM- APDs) have already been exploited for optical time domain reflectometry (OTDR). Better than 1 cm spatial resolution in Rayleigh scattering detection was demonstrated. Distributed and quasi-distributed optical fiber sensors can take advantage of the capabilities of GM-APDs. Extensive studies have recently disclosed the main characteristics and limitations of silicon devices, both commercially available and developmental. In this paper we report an analysis of the performance of these detectors. The main characteristics of GM-APDs of interest for distributed optical fiber sensors are briefly reviewed. Command electronics (active quenching) is then introduced. The detector timing performance sets the maximum spatial resolution in experiments employing OTDR techniques. We highlight that the achievable time resolution depends on the physics of the avalanche spreading over the device area. On the basis of these results, trade-off between the important parameters (quantum efficiency, time resolution, background noise, and afterpulsing effects) is considered. Finally, we show first results on Germanium devices, capable of single photon sensitivity at 1.3 and 1.5 micrometers with sub- nanosecond time resolution.

  5. Turbine-blade tip clearance and tip timing measurements using an optical fiber bundle sensor

    Science.gov (United States)

    Garcia, Iker; Beloki, Josu; Zubia, Joseba; Durana, Gaizka; Aldabaldetreku, Gotzon

    2013-04-01

    Traditional limitations of capacitive, inductive or discharging probe sensor for tip timing and tip clearance measurements are overcome by reflective intensity modulated optical fiber sensors. This paper presents the signals and results corresponding to a one stage turbine rig which rotor has 146 blades, obtained from a transonic wind-tunnel test. The probe is based on a trifurcated bundle of optical fibers that is mounted on turbine casing. It is composed of a central illuminating fiber that guides the light from a laser to the turbine blade, and two concentric rings of receiving fibers that collect the reflected light. Two photodetectors turn this reflected light signal from the receiving rings into voltage. The electrical signals are acquired and saved by a high-sample-rate oscilloscope. In tip clearance calculations the ratio of the signals provided by each ring of receiving fibers is evaluated and translated into distance. In the case of tip timing measurements, only one of the signals is considered to get the arrival time of the blade. The differences between the real and theoretical arrival times of the blades are used to obtain the deflections amplitude. The system provides the travelling wave spectrum, which presents the average vibration amplitude of the blades at a certain nodal diameter. The reliability of the results in the turbine rig testing facilities suggests the possibility of performing these measurements in real turbines under real working conditions.

  6. Feasibility study of the optical fiber Bragg grating sensors in radiation environment

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Kaoru; Kimura, Atsushi; Nakazawa, Masaharu [Tokyo Univ., Dept. of Quantum Engineering and Systems Science, Tokyo (Japan); Takahashi, Hiroyuki [Tokyo Univ., Center of Engineering, Research into Artifacts, Tokyo (Japan); Ariyoshi, Masahiko [Japan Nuclear Cycle Development Inst., Oarai, Ibaraki (Japan)

    2002-09-01

    Applicability of an optical fiber Bragg grating (FBG)-based vibration sensor to radiation environment was investigated for monitoring nuclear plants. The FBG sensor is a kind of optical fiber sensors which is developing rapidly in recent years. FBGs reflect light which fulfill the Bragg condition {lambda} = 2 n L, where {lambda} is the wave length of reflecting light, n and L are the effective refractive index and length of the modulation period in grating part, respectively. The strain on FBGs influences on n and L and causes shift of {lambda}. The sensitivity to strain of FBG were investigated. The FBGs was irradiated with gamma-rays to investigate the irradiation effects on the FBGs. The Bragg wavelength of FBGs is not affected by gamma-rays up to 1.0 MGy of total absorbed dose. In vibration measurement system, two FBGs were attached to a thin iron plate. Each FBG was set up both side of the thin plate and spliced in series. An audio speaker was used as a vibration source. FBGs were irradiated at the dose rate of 50Gy/h and the vibration were observed in situ. Input signals from oscillator, the output from FBG sensors and the power spectra of the two signals were measured. The output signal was very noisy, however, the peak of the frequency is corresponding. The noise seemed to be arisen during the vibration traveled between the speaker and the plate and considered to be not essential. As a result, it is shown that a change of frequency at the vibration source could be followed by FBG-based sensors. To reduce the noise, the method for conducting the vibration to FBGs should be improved. (M. Suetake)

  7. Feasibility study of the optical fiber Bragg grating sensors in radiation environment

    International Nuclear Information System (INIS)

    Fujita, Kaoru; Kimura, Atsushi; Nakazawa, Masaharu; Takahashi, Hiroyuki; Ariyoshi, Masahiko

    2002-01-01

    Applicability of an optical fiber Bragg grating (FBG)-based vibration sensor to radiation environment was investigated for monitoring nuclear plants. The FBG sensor is a kind of optical fiber sensors which is developing rapidly in recent years. FBGs reflect light which fulfill the Bragg condition λ = 2 n L, where λ is the wave length of reflecting light, n and L are the effective refractive index and length of the modulation period in grating part, respectively. The strain on FBGs influences on n and L and causes shift of λ. The sensitivity to strain of FBG were investigated. The FBGs was irradiated with gamma-rays to investigate the irradiation effects on the FBGs. The Bragg wavelength of FBGs is not affected by gamma-rays up to 1.0 MGy of total absorbed dose. In vibration measurement system, two FBGs were attached to a thin iron plate. Each FBG was set up both side of the thin plate and spliced in series. An audio speaker was used as a vibration source. FBGs were irradiated at the dose rate of 50Gy/h and the vibration were observed in situ. Input signals from oscillator, the output from FBG sensors and the power spectra of the two signals were measured. The output signal was very noisy, however, the peak of the frequency is corresponding. The noise seemed to be arisen during the vibration traveled between the speaker and the plate and considered to be not essential. As a result, it is shown that a change of frequency at the vibration source could be followed by FBG-based sensors. To reduce the noise, the method for conducting the vibration to FBGs should be improved. (M. Suetake)

  8. Low Cost Plastic Optical Fiber Pressure Sensor Embedded in Mattress for Vital Signal Monitoring.

    Science.gov (United States)

    Sartiano, Demetrio; Sales, Salvador

    2017-12-13

    The aim of this paper is to report the design of a low-cost plastic optical fiber (POF) pressure sensor, embedded in a mattress. We report the design of a multipoint sensor, a cheap alternative to the most common fiber sensors. The sensor is implemented using Arduino board, standard LEDs for optical communication in POF (λ = 645 nm) and a silicon light sensor. The Super ESKA ® plastic fibers were used to implement the fiber intensity sensor, arranged in a 4 × 4 matrix. During the breathing cycles, the force transmitted from the lungs to the thorax is in the order of tens of Newtons, and the respiration rate is of one breath every 2-5 s (0.2-0.5 Hz). The sensor has a resolution of force applied on a single point of 2.2-4.5%/N on the normalized voltage output, and a bandwidth of 10 Hz, it is then suitable to monitor the respiration movements. Another issue to be addressed is the presence of hysteresis over load cycles. The sensor was loaded cyclically to estimate the drift of the system, and the hysteresis was found to be negligible.

  9. Low Cost Plastic Optical Fiber Pressure Sensor Embedded in Mattress for Vital Signal Monitoring

    Directory of Open Access Journals (Sweden)

    Demetrio Sartiano

    2017-12-01

    Full Text Available The aim of this paper is to report the design of a low-cost plastic optical fiber (POF pressure sensor, embedded in a mattress. We report the design of a multipoint sensor, a cheap alternative to the most common fiber sensors. The sensor is implemented using Arduino board, standard LEDs for optical communication in POF (λ = 645 nm and a silicon light sensor. The Super ESKA® plastic fibers were used to implement the fiber intensity sensor, arranged in a 4 × 4 matrix. During the breathing cycles, the force transmitted from the lungs to the thorax is in the order of tens of Newtons, and the respiration rate is of one breath every 2–5 s (0.2–0.5 Hz. The sensor has a resolution of force applied on a single point of 2.2–4.5%/N on the normalized voltage output, and a bandwidth of 10 Hz, it is then suitable to monitor the respiration movements. Another issue to be addressed is the presence of hysteresis over load cycles. The sensor was loaded cyclically to estimate the drift of the system, and the hysteresis was found to be negligible.

  10. Building a digital scale using optical fiber sensors for teaching shift

    International Nuclear Information System (INIS)

    Diaz, L.; Torres, C.

    2016-01-01

    In this article is show the implementation of an electronic balance using Optics fibers for teaching displacement sensors. The system is based on displacement detections using an fiber optical bifurcated as active optical medium, commercial pointers of power lesser 10mW, a converter sensor of light intensities at electric, a PIC for signal processing and LCD to display the data. The importance of the implemented prototype lies in having an electronic device developed by students of the electives of optoelectronic, applying displacement sensing, also, the balance built could be used in zones classified with electromagnetic interference and in the areas hazardous by not using or storing sufficient electrical or thermal energy it can ignite a flammable atmosphere environment. (Author

  11. Improved extrinsic polymer optical fiber sensors for gamma-ray monitoring in radioprotection applications

    Science.gov (United States)

    de Andrés, A. I.; Esteban, Ó.; Embid, M.

    2017-08-01

    Gamma radiation detection in the range of 662 keV, the reference for environmental protection, is done through extrinsic optical fiber sensors. The fluorescence rendered by an inorganic scintillator when irradiated with such gamma rays is gathered by a modified polymer optical fiber tip. This modification increases the recorded signal when compared with plain unaltered fiber. Two fiber tip modification are then compared in terms of light gathering capability. A chemically etched fiber, in which the cladding and part of the core are removed, and a tapered fiber in which the core-cladding structure is kept. Both structures are comparable in length and final diameter, and show linear response in the tested range up to 2 Gy/h air Kerma rate. The etched fiber shows a higher slope than the tapered one, although both improve the signal gathered by a plain fiber tip. The easy fabrication and handling of the reported transducers, together with the improved signal gathering, allow to reduce the overall system budget with the use of low-cost optoelectronics in the detection stage. This offers a significant improvement for surveillance systems in radioprotection applications, in which presence of gamma radiation coming out accidental leakage or spurious sources activity is the main target.

  12. Alkali-resistant low-temperature atomic-layer-deposited oxides for optical fiber sensor overlays

    Science.gov (United States)

    Kosiel, K.; Dominik, M.; Ściślewska, I.; Kalisz, M.; Guziewicz, M.; Gołaszewska, K.; Niedziółka-Jonsson, J.; Bock, W. J.; Śmietana, M.

    2018-04-01

    This paper presents an investigation of properties of selected metallic oxides deposited at a low temperature (100 °C) by atomic layer deposition (ALD) technique, relating to their applicability as thin overlays for optical fiber sensors resistant in alkaline environments. Hafnium oxide (Hf x O y with y/x approx. 2.70), tantalum oxide (Ta x O y with y/x approx. 2.75) and zirconium oxide (Zr x O y with y/x approx. 2.07), which deposition was based, respectively, on tetrakis(ethylmethyl)hafnium, tantalum pentachloride and tetrakis(ethylmethyl)zirconium with deionized water, were tested as thin layers on planar Si (100) and glass substrates. Growth per cycle (GPC) in the ALD processes was 0.133-0.150 nm/cycle. Run-to-run GPC reproducibility of the ALD processes was best for Hf x O y (0.145 ± 0.001 nm/cycle) and the poorest for Ta x O y (0.133 ± 0.003 nm/cycle). Refractive indices n of the layers were 2.00-2.10 (at the wavelength λ = 632 nm), with negligible k value (at λ for 240-930 nm). The oxides examined by x-ray diffractometry proved to be amorphous, with only small addition of crystalline phases for the Zr x O y . The surfaces of the oxides had grainy but smooth topographies with root-mean square roughness ˜0.5 nm (at 10 × 10 μm2 area) according to atomic force microscopy. Ellipsometric measurements, by contrast, suggest rougher surfaces for the Zr x O y layers. The surfaces were also slightly rougher on the glass-based samples than on the Si-based ones. Nanohardness and Young modules were 4.90-8.64 GPa and 83.7-104.4 GPa, respectively. The tests of scratch resistance revealed better tribological properties for the Hf x O y and the Ta x O y than for the Zr x O y . The surfaces were hydrophilic, with wetting angles of 52.5°-62.9°. The planar oxides on Si, being resistive even to concentrated alkali (pH 14), proved to be significantly more alkali-resistive than Al2O3. The Ta x O y overlay was deposited on long-period grating sensor induced in optical

  13. Optical fiber sensor based on surface plasmon resonance for rapid detection of avian influenza virus subtype H6: Initial studies.

    Science.gov (United States)

    Zhao, Xihong; Tsao, Yu-Chia; Lee, Fu-Jung; Tsai, Woo-Hu; Wang, Ching-Ho; Chuang, Tsung-Liang; Wu, Mu-Shiang; Lin, Chii-Wann

    2016-07-01

    A side-polished fiber optic surface plasmon resonance (SPR) sensor was fabricated to expose the core surface and then deposited with a 40 nm thin gold film for the near surface sensing of effective refractive index changes with surface concentration or thickness of captured avian influenza virus subtype H6. The detection surface of the SPR optical fiber sensor was prepared through the plasma modification method for binding a self-assembled monolayer of isopropanol chemically on the gold surface of the optical fiber. Subsequently, N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide/N-hydroxysuccinimide was activated to enable EB2-B3 monoclonal antibodies to capture A/chicken/Taiwan/2838V/00 (H6N1) through a flow injection system. The detection limit of the fabricated optical fiber sensor for A/chicken/Taiwan/2838V/00 was 5.14 × 10(5) EID50/0.1 mL, and the response time was 10 min on average. Moreover, the fiber optic sensor has the advantages of a compact size and low cost, thus rendering it suitable for online and remote sensing. The results indicated that the optical fiber sensor can be used for epidemiological surveillance and diagnosing of avian influenza subtype H6 rapidly. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Micro-structured optical fiber sensor for simultaneous measurement of temperature and refractive index

    Science.gov (United States)

    Liu, Ying-gang; Liu, Xin; Ma, Cheng-ju; Zhou, Yu-min

    2018-03-01

    Through using micro-machining method for optical fiber sensor, a kind of miniature, compact and composite structural all-fiber sensor is presented. Based on manufacturing two micro-holes with certain distance in ordinary single-mode fiber Bragg grating (FBG) by excimer laser processing technique, we fabricate a dual Fabry-Perot-FBG (FP-FBG) composite fiber interferometric sensor, which can be used in simultaneous measurement for liquid's refractive index (RI) and temperature change. Due to every micro-hole and the dual micro-holes in fiber acting as different Fabry-Perot (FP) cavities, this kind of sensor has not only different RI sensitivities but also different temperature sensitivities, which are corresponding to the wavelength shifts of the fine interference fringes and spectral envelope, respectively. The experimental results show that the spectral wavelength shift keep better linear response for temperature and RI change, so that we can select the higher temperature and RI sensitivities as well as the analyzed sensitivities of FBG to utilize them for constituting a sensitivity coefficients matrix. Finally, the variations of liquid's temperature and RI are detected effectively, and the resolutions can reach to 0.1 °C and 1.0 ×10-5 RIU. These characteristics are what other single-type sensors don't have, so that this kind of all-fiber dual FP-FBG composite fiber interferometric sensor can be used in extremely tiny liquid environment for measuring different physical quantities simultaneously.

  15. Development of a position sensor based on a four quadrant structured optic fiber bundle

    International Nuclear Information System (INIS)

    Boukellal, Younes; Ducourtieux, Sebastien

    2015-01-01

    This article reports on the development of a new kind of 2D displacement sensor based on an optic fiber bundle whose fiber arrangement has been customized to provide an input sensitive surface with four quadrants. The fibers of each quadrant are regrouped to form four output arms. The aim is to reach behavior similar to that of a quad cell photodiode when illuminated by a laser spot. In this paper, we present the motivations for developing such a sensor and its design. Prior to the fabrication of a first prototype, the optic fiber bundle has been modelled and compared to a quad cell photodiode. It has an active surface which is 10 mm in diameter and which comprises 40 000 fibers of 50 µm core diameter. For this experimental test, a specific electronic conditioning circuit has been developed to process the signals. From both modelled and experimental results, fiber optic bundle and quad cell photodiode behavior has proved to be very similar, provided that the number of fibers is sufficient to achieve a statistical effect on the detected displacement, i.e. the laser spot diameter is rightly chosen as a function of the fiber diameter. For the use of the bundle as position sensor, a laser spot size of 5 mm has been fixed to achieve a good compromise between sensitivity and displacement range. With this spot size, sensitivity and displacement range have been experimentally evaluated to 2 mV µm −1 and 3.8 mm respectively with a corresponding displacement resolution of 5 nm in the best case. (paper)

  16. Molecular imprinted polymer-coated optical fiber sensor for the identification of low molecular weight molecules.

    Science.gov (United States)

    Lépinay, Sandrine; Ianoul, Anatoli; Albert, Jacques

    2014-10-01

    A biomimetic optical probe for detecting low molecular weight molecules (maltol, 3-hydroxy-2-methyl-4H-pyran-4-one, molecular weight of 126.11 g/mol), was designed, fabricated, and characterized. The sensor couples a molecular imprinted polymer (MIP) and the Bragg grating refractometry technology into an optical fiber. The probe is fabricated first by inscribing tilted grating planes in the core of the fiber, and then by photopolymerization to immobilize a maltol imprinted MIP on the fiber cladding surface over the Bragg grating. The sensor response to the presence of maltol in different media is obtained by spectral interrogation of the fiber transmission signal. The results showed that the limit of detection of the sensor reached 1 ng/mL in pure water with a sensitivity of 6.3 × 10(8)pm/M. The selectivity of the sensor against other compounds and its reusability were also studied experimentally. Finally, the unambiguous detection of concentrations as little as 10nM of maltol in complex media (real food samples) by the MIP-coated tilted fiber Bragg grating sensor was demonstrated. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Crossed Optical Fiber Sensor Arrays for High-Spatial-Resolution Sensing: Application to Dissolved Oxygen Concentration Measurements

    Directory of Open Access Journals (Sweden)

    M. Veronica Rigo

    2012-01-01

    Full Text Available Optical fiber sensors using luminescent probes located along an optical fiber in the cladding of this fiber are of great interest for monitoring physical and chemical properties in their environment. The interrogation of a luminophore with a short laser pulse propagating through the fiber core allows for the measurement of the location of these luminophores. To increase the spatial resolution of such a measurements and to measure multiple analytes and properties in a confined space, a crossed optical fiber sensing platform can be employed. Here we describe the application of this platform to measuring the concentration of dissolved oxygen. The sensor is based on luminescence quenching of a ruthenium complex immobilized in a highly crosslinked film and covalently attached to the optical fibers. Both luminescence-intensity and luminescence-lifetime changes of the sensor molecules in response to changes in the concentration of oxygen dissolved in water are reported. For luminescence-intensity measurements, a second adjacent sensor region is employed as reference to account for laser pulse energy fluctuations. Enhanced quenching response in water is demonstrated by the use of organically modified poly(ethylene glycol precursors, which increase the hydrophobicity of the film surface.

  18. High-quality phase-shifted Bragg grating sensor inscribed with only one laser pulse in a polymer optical fiber

    DEFF Research Database (Denmark)

    Marques, C. A. F.; Pospori, A.; Pereira, L.

    2017-01-01

    We present the first phase-shifted polymer optical fiber Bragg grating sensor inscribed with only one KrF laser pulse. The phase shift defect was created directly during the grating inscription process by placing a very narrow blocking aperture, in the center of the UV beam. One laser pulse...

  19. Distributed Optical Fiber Sensors Based on Optical Frequency Domain Reflectometry: A review.

    Science.gov (United States)

    Ding, Zhenyang; Wang, Chenhuan; Liu, Kun; Jiang, Junfeng; Yang, Di; Pan, Guanyi; Pu, Zelin; Liu, Tiegen

    2018-04-03

    Distributed optical fiber sensors (DOFS) offer unprecedented features, the most unique one of which is the ability of monitoring variations of the physical and chemical parameters with spatial continuity along the fiber. Among all these distributed sensing techniques, optical frequency domain reflectometry (OFDR) has been given tremendous attention because of its high spatial resolution and large dynamic range. In addition, DOFS based on OFDR have been used to sense many parameters. In this review, we will survey the key technologies for improving sensing range, spatial resolution and sensing performance in DOFS based on OFDR. We also introduce the sensing mechanisms and the applications of DOFS based on OFDR including strain, stress, vibration, temperature, 3D shape, flow, refractive index, magnetic field, radiation, gas and so on.

  20. Clad modified optical fiber gas sensors based on nanocrystalline nickel oxide embedded coatings

    Science.gov (United States)

    Yamini, K.; Renganathan, B.; Ganesan, A. R.; Prakash, T.

    2017-07-01

    A clad modified optical fiber gas sensor for sensing volatile organic compound vapours (VOCs) such as formaldehyde (HCHO), ammonia (NH3), ethanol (C2H5OH) and methanol (CH3OH) up to 500 ppm was studied using nanocrystalline nickel oxide embedded coatings. Prior to the measurements, nickel oxide in two different crystallite sizes such as 24 nm and 76 nm was synthesized by calcination of reverse precipitated nickel hydroxide subsequently at 450 °C and 900 °C for 30 min. Then, samples physical properties were characterized using X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM). Our gas sensing measurement concludes that the lower crystallite size (24 nm) nickel oxide nanocrystals exhibits superior performance to formaldehyde and ethanol vapours as compared with other two VOCs, the observed experimental results were discussed in detail.

  1. Distributed Optical Fiber Sensors Based on Optical Frequency Domain Reflectometry: A review

    Science.gov (United States)

    Wang, Chenhuan; Liu, Kun; Jiang, Junfeng; Yang, Di; Pan, Guanyi; Pu, Zelin; Liu, Tiegen

    2018-01-01

    Distributed optical fiber sensors (DOFS) offer unprecedented features, the most unique one of which is the ability of monitoring variations of the physical and chemical parameters with spatial continuity along the fiber. Among all these distributed sensing techniques, optical frequency domain reflectometry (OFDR) has been given tremendous attention because of its high spatial resolution and large dynamic range. In addition, DOFS based on OFDR have been used to sense many parameters. In this review, we will survey the key technologies for improving sensing range, spatial resolution and sensing performance in DOFS based on OFDR. We also introduce the sensing mechanisms and the applications of DOFS based on OFDR including strain, stress, vibration, temperature, 3D shape, flow, refractive index, magnetic field, radiation, gas and so on. PMID:29614024

  2. Distributed Optical Fiber Sensors Based on Optical Frequency Domain Reflectometry: A review

    Directory of Open Access Journals (Sweden)

    Zhenyang Ding

    2018-04-01

    Full Text Available Distributed optical fiber sensors (DOFS offer unprecedented features, the most unique one of which is the ability of monitoring variations of the physical and chemical parameters with spatial continuity along the fiber. Among all these distributed sensing techniques, optical frequency domain reflectometry (OFDR has been given tremendous attention because of its high spatial resolution and large dynamic range. In addition, DOFS based on OFDR have been used to sense many parameters. In this review, we will survey the key technologies for improving sensing range, spatial resolution and sensing performance in DOFS based on OFDR. We also introduce the sensing mechanisms and the applications of DOFS based on OFDR including strain, stress, vibration, temperature, 3D shape, flow, refractive index, magnetic field, radiation, gas and so on.

  3. Tunable Polymer Fiber Bragg Grating (FBG) Inscription: Fabrication of Dual-FBG Temperature Compensated Polymer Optical Fiber Strain Sensors

    DEFF Research Database (Denmark)

    Yuan, Scott Wu; Stefani, Alessio; Bang, Ole

    2012-01-01

    We demonstrate stable wavelength tunable inscription of polymer optical fiber Bragg gratings (FBGs). By straining the fiber during FBG inscription, we linearly tune the center wavelength over 7 nm with less than 1% strain. Above 1% strain, the tuning curve saturates and we show a maximum tuning...... of 12 nm with 2.25% strain. We use this inscription method to fabricate a dual-FBG strain sensor in a poly (methyl methacrylate) single-mode microstructured polymer optical fiber and demonstrate temperature compensated strain sensing around 850 nm....

  4. Tailoring properties of lossy-mode resonance optical fiber sensors with atomic layer deposition technique

    Science.gov (United States)

    Kosiel, Kamil; Koba, Marcin; Masiewicz, Marcin; Śmietana, Mateusz

    2018-06-01

    The paper shows application of atomic layer deposition (ALD) technique as a tool for tailoring sensorial properties of lossy-mode-resonance (LMR)-based optical fiber sensors. Hafnium dioxide (HfO2), zirconium dioxide (ZrO2), and tantalum oxide (TaxOy), as high-refractive-index dielectrics that are particularly convenient for LMR-sensor fabrication, were deposited by low-temperature (100 °C) ALD ensuring safe conditions for thermally vulnerable fibers. Applicability of HfO2 and ZrO2 overlays, deposited with ALD-related atomic level thickness accuracy for fabrication of LMR-sensors with controlled sensorial properties was presented. Additionally, for the first time according to our best knowledge, the double-layer overlay composed of two different materials - silicon nitride (SixNy) and TaxOy - is presented for the LMR fiber sensors. The thin films of such overlay were deposited by two different techniques - PECVD (the SixNy) and ALD (the TaxOy). Such approach ensures fast overlay fabrication and at the same time facility for resonant wavelength tuning, yielding devices with satisfactory sensorial properties.

  5. Optical fiber chemiluminescence sensor for iron (II) ion based on immobilized luminol

    International Nuclear Information System (INIS)

    Alipao, Arthur A.; Sevilla, Fortunato III.

    1999-01-01

    A chemiluminescence (CL) sensor for iron (II) was developed based on the catalytic action of the analyte on the CL reaction between luminol and oxygen. The reagents were immobilized on a cellulose membrane and set on a reaction cell which was coupled by means of an optical fiber to a spectrofluorometer. The concentration of iron(II) was quantified by measuring the intensity of the light generated from the CL reaction. The response of the sensor system was rapid and highly reproducible. Good sensitivity was displayed by the sensor system over the five orders of magnitude of iron(II) ion concentration. The calibration curve consisted of two portions: (1) a linear range at lower concentrations (7.5 x 10 -7 M to 1.0 x 10 -4 M) exhibiting a positive slope arising from a catalytic action, and (2) a linear range at higher concentrations (5.0 x 10 -2 M to 2.5 x 10 -4 M) wherein the slope is negative due to an inhibitory action of iron(II) on the CL reaction. The sensor system was highly selective for iron(II) ions. (Author)

  6. Distributed Long-Gauge Optical Fiber Sensors Based Self-Sensing FRP Bar for Concrete Structure.

    Science.gov (United States)

    Tang, Yongsheng; Wu, Zhishen

    2016-02-25

    Brillouin scattering-based distributed optical fiber (OF) sensing technique presents advantages for concrete structure monitoring. However, the existence of spatial resolution greatly decreases strain measurement accuracy especially around cracks. Meanwhile, the brittle feature of OF also hinders its further application. In this paper, the distributed OF sensor was firstly proposed as long-gauge sensor to improve strain measurement accuracy. Then, a new type of self-sensing fiber reinforced polymer (FRP) bar was developed by embedding the packaged long-gauge OF sensors into FRP bar, followed by experimental studies on strain sensing, temperature sensing and basic mechanical properties. The results confirmed the superior strain sensing properties, namely satisfied accuracy, repeatability and linearity, as well as excellent mechanical performance. At the same time, the temperature sensing property was not influenced by the long-gauge package, making temperature compensation easy. Furthermore, the bonding performance between self-sensing FRP bar and concrete was investigated to study its influence on the sensing. Lastly, the sensing performance was further verified with static experiments of concrete beam reinforced with the proposed self-sensing FRP bar. Therefore, the self-sensing FRP bar has potential applications for long-term structural health monitoring (SHM) as embedded sensors as well as reinforcing materials for concrete structures.

  7. Recent developments in the use of plastic optical fiber for an embedded wear sensor

    Science.gov (United States)

    Cohen, Edward I.; Mastro, Stephen A.; Nemarich, Christopher P.; Korczynski, Joseph F., Jr.; Jarrett, Andrew W.; Jones, Wayne C.

    1999-05-01

    This paper describes recent developments of a practical, low cost embedded plastic optical fiber (POF) wear sensor system for the condition based maintenance of external outboard water lubricated bearings aboard U.S. Navy Ships. The benefit of this measurement system over the status quo is the ability to remotely monitor bearing wear. The Embedded Wear Sensor system (Navy invention disclosure #78,570) features a sacrificial wear fiber embedded into the nitrile rubber bearing. This fiber may also act as a conduit for the transmission of pressure and temperature data that may be resolved into alignment data. The authors selected a commercially-off-the- shelf plastic fiber for the sensor because of its material compatibility with the nitrile rubber bearing staves in terms of flexural modulus and wear properties. Presented herein is a description of the system concept, the results of non-linear finite element analysis, market survey of POF, mold studies, small scale prototyping and abrasive wear testing. A description of the sensor concept and the results of the preliminary finite element analysis of the bearing stave geometry are presented. Preliminary results of molding and glue bonding POF in nitrile rubber and then abrasive wear testing indicate that this is a viable concept.

  8. Performance Analysis of a Noncontact Plastic Fiber Optical Fiber Displacement Sensor with Compensation of Target Reflectivity

    Directory of Open Access Journals (Sweden)

    Daniele Tosi

    2013-01-01

    Full Text Available An inexpensive fiber-based noncontact distance sensor specific for monitoring short-range displacements in micromachining applications is presented. To keep the overall costs low, the sensor uses plastic optical fibers and an intensiometric approach based on the received light intensity after the reflection from the target whose displacement has to be measured. A suitable target reflectivity compensation technique is implemented to mitigate the effects due to target surface nonuniformity or ageing. The performances of the sensor are first evaluated for different fiber configurations and target reflectivity profiles and positions using a numerical method based on Monte Carlo simulations. Then, experimental validations on a configuration designed to work up to 1.5 mm have been conducted. The results have confirmed the validity of the proposed sensor architecture, which demonstrated excellent compensation capabilities, with errors below 0.04 mm in the (0-1 mm range regardless the color and misalignment of the target.

  9. Fabricating Optical Fiber Imaging Sensors Using Inkjet Printing Technology: a pH Sensor Proof-of-Concept

    Energy Technology Data Exchange (ETDEWEB)

    Carter, J C; Alvis, R M; Brown, S B; Langry, K C; Wilson, T S; McBride, M T; Myrick, M L; Cox, W R; Grove, M E; Colston, B W

    2005-03-01

    We demonstrate the feasibility of using Drop-on-Demand microjet printing technology for fabricating imaging sensors by reproducibly printing an array of photopolymerizable sensing elements, containing a pH sensitive indicator, on the surface of an optical fiber image guide. The reproducibility of the microjet printing process is excellent for microdot (i.e. micron-sized polymer) sensor diameter (92.2 {+-} 2.2 microns), height (35.0 {+-} 1.0 microns), and roundness (0.00072 {+-} 0.00023). pH sensors were evaluated in terms of pH sensing ability ({le}2% sensor variation), response time, and hysteresis using a custom fluorescence imaging system. In addition, the microjet technique has distinct advantages over other fabrication methods, which are discussed in detail.

  10. Embedded Distributed Optical Fiber Sensors in Reinforced Concrete Structures-A Case Study.

    Science.gov (United States)

    Barrias, António; Casas, Joan R; Villalba, Sergi

    2018-03-26

    When using distributed optical fiber sensors (DOFS) on reinforced concrete structures, a compromise must be achieved between the protection requirements and robustness of the sensor deployment and the accuracy of the measurements both in the uncracked and cracked stages and under loading, unloading and reloading processes. With this in mind the authors have carried out an experiment where polyimide-coated DOFS were installed on two concrete beams, both embedded in the rebar elements and also bonded to the concrete surface. The specimens were subjected to a three-point load test where after cracking, they are unloaded and reloaded again to assess the capability of the sensor when applied to a real loading scenarios in concrete structures. Rayleigh Optical Frequency Domain Reflectometry (OFDR) was used as the most suitable technique for crack detection in reinforced concrete elements. To verify the reliability and accuracy of the DOFS measurements, additional strain gauges were also installed at three locations along the rebar. The results show the feasibility of using a thin coated polyimide DOFS directly bonded on the reinforcing bar without the need of indention or mechanization. A proposal for a Spectral Shift Quality (SSQ) threshold is also obtained and proposed for future works when using polyimide-coated DOFS bonded to rebars with cyanoacrylate adhesive.

  11. Plasmonic Optical Fiber Sensor Based on Double Step Growth of Gold Nano-Islands

    Directory of Open Access Journals (Sweden)

    José M. M. M. de Almeida

    2018-04-01

    Full Text Available It is presented the fabrication and characterization of optical fiber sensors for refractive index measurement based on localized surface plasmon resonance (LSPR with gold nano-islands obtained by single and by repeated thermal dewetting of gold thin films. Thin films of gold deposited on silica (SiO2 substrates and produced by different experimental conditions were analyzed by Scanning Electron Microscope/Dispersive X-ray Spectroscopy (SEM/EDS and optical means, allowing identifying and characterizing the formation of nano-islands. The wavelength shift sensitivity to the surrounding refractive index of sensors produced by single and by repeated dewetting is compared. While for the single step dewetting, a wavelength shift sensitivity of ~60 nm/RIU was calculated, for the repeated dewetting, a value of ~186 nm/RIU was obtained, an increase of more than three times. It is expected that through changing the fabrication parameters and using other fiber sensor geometries, higher sensitivities may be achieved, allowing, in addition, for the possibility of tuning the plasmonic frequency.

  12. Oil pipeline geohazard monitoring using optical fiber FBG strain sensors (Conference Presentation)

    Science.gov (United States)

    Salazar-Ferro, Andres; Mendez, Alexis

    2016-04-01

    Pipelines are naturally vulnerable to operational, environmental and man-made effects such as internal erosion and corrosion; mechanical deformation due to geophysical risks and ground movements; leaks from neglect and vandalism; as well as encroachments from nearby excavations or illegal intrusions. The actual detection and localization of incipient and advanced faults in pipelines is a very difficult, expensive and inexact task. Anything that operators can do to mitigate the effects of these faults will provide increased reliability, reduced downtime and maintenance costs, as well as increased revenues. This talk will review the on-line monitoring of an extensive network of oil pipelines in service in Colombia using optical fiber Bragg grating (FBG) strain sensors for the measurement of strains and bending caused by geohazard risks such as soil movements, landslides, settlements, flooding and seismic activity. The FBG sensors were mounted on the outside of the pipelines at discrete locations where geohazard risk was expected. The system has been in service for the past 3 years with over 1,000 strain sensors mounted. The technique has been reliable and effective in giving advanced warning of accumulated pipeline strains as well as possible ruptures.

  13. Plasmonic Optical Fiber Sensor Based on Double Step Growth of Gold Nano-Islands

    Science.gov (United States)

    Vasconcelos, Helena

    2018-01-01

    It is presented the fabrication and characterization of optical fiber sensors for refractive index measurement based on localized surface plasmon resonance (LSPR) with gold nano-islands obtained by single and by repeated thermal dewetting of gold thin films. Thin films of gold deposited on silica (SiO2) substrates and produced by different experimental conditions were analyzed by Scanning Electron Microscope/Dispersive X-ray Spectroscopy (SEM/EDS) and optical means, allowing identifying and characterizing the formation of nano-islands. The wavelength shift sensitivity to the surrounding refractive index of sensors produced by single and by repeated dewetting is compared. While for the single step dewetting, a wavelength shift sensitivity of ~60 nm/RIU was calculated, for the repeated dewetting, a value of ~186 nm/RIU was obtained, an increase of more than three times. It is expected that through changing the fabrication parameters and using other fiber sensor geometries, higher sensitivities may be achieved, allowing, in addition, for the possibility of tuning the plasmonic frequency. PMID:29677108

  14. A Review of Distributed Optical Fiber Sensors for Civil Engineering Applications

    Science.gov (United States)

    Barrias, António; Casas, Joan R.; Villalba, Sergi

    2016-01-01

    The application of structural health monitoring (SHM) systems to civil engineering structures has been a developing studied and practiced topic, that has allowed for a better understanding of structures’ conditions and increasingly lead to a more cost-effective management of those infrastructures. In this field, the use of fiber optic sensors has been studied, discussed and practiced with encouraging results. The possibility of understanding and monitor the distributed behavior of extensive stretches of critical structures it’s an enormous advantage that distributed fiber optic sensing provides to SHM systems. In the past decade, several R & D studies have been performed with the goal of improving the knowledge and developing new techniques associated with the application of distributed optical fiber sensors (DOFS) in order to widen the range of applications of these sensors and also to obtain more correct and reliable data. This paper presents, after a brief introduction to the theoretical background of DOFS, the latest developments related with the improvement of these products by presenting a wide range of laboratory experiments as well as an extended review of their diverse applications in civil engineering structures. PMID:27223289

  15. Plasmonic Optical Fiber Sensor Based on Double Step Growth of Gold Nano-Islands.

    Science.gov (United States)

    de Almeida, José M M M; Vasconcelos, Helena; Jorge, Pedro A S; Coelho, Luis

    2018-04-20

    It is presented the fabrication and characterization of optical fiber sensors for refractive index measurement based on localized surface plasmon resonance (LSPR) with gold nano-islands obtained by single and by repeated thermal dewetting of gold thin films. Thin films of gold deposited on silica (SiO₂) substrates and produced by different experimental conditions were analyzed by Scanning Electron Microscope/Dispersive X-ray Spectroscopy (SEM/EDS) and optical means, allowing identifying and characterizing the formation of nano-islands. The wavelength shift sensitivity to the surrounding refractive index of sensors produced by single and by repeated dewetting is compared. While for the single step dewetting, a wavelength shift sensitivity of ~60 nm/RIU was calculated, for the repeated dewetting, a value of ~186 nm/RIU was obtained, an increase of more than three times. It is expected that through changing the fabrication parameters and using other fiber sensor geometries, higher sensitivities may be achieved, allowing, in addition, for the possibility of tuning the plasmonic frequency.

  16. A Review of Distributed Optical Fiber Sensors for Civil Engineering Applications

    Directory of Open Access Journals (Sweden)

    António Barrias

    2016-05-01

    Full Text Available The application of structural health monitoring (SHM systems to civil engineering structures has been a developing studied and practiced topic, that has allowed for a better understanding of structures’ conditions and increasingly lead to a more cost-effective management of those infrastructures. In this field, the use of fiber optic sensors has been studied, discussed and practiced with encouraging results. The possibility of understanding and monitor the distributed behavior of extensive stretches of critical structures it’s an enormous advantage that distributed fiber optic sensing provides to SHM systems. In the past decade, several R & D studies have been performed with the goal of improving the knowledge and developing new techniques associated with the application of distributed optical fiber sensors (DOFS in order to widen the range of applications of these sensors and also to obtain more correct and reliable data. This paper presents, after a brief introduction to the theoretical background of DOFS, the latest developments related with the improvement of these products by presenting a wide range of laboratory experiments as well as an extended review of their diverse applications in civil engineering structures.

  17. No-core fiber-based highly sensitive optical fiber pH sensor.

    Science.gov (United States)

    Bhardwaj, Vanita; Pathak, Akhilesh Kumar; Singh, Vinod Kumar

    2017-05-01

    The present work describes the fabrication and characterization of an optical fiber pH sensor using a sol–gel technique. The sensing head configuration is incorporated using a short section of no-core fiber, coated with tetraethyl orthosilicate and spliced at the end of a single mode fiber with a bulge. Different types of indicators (bromophenol blue, cresol red, and chlorophenol red) were used to achieve a wide pH range from 2 to 13. High sensitivities of the fabricated device were found to be 1.02 and ? 0.93 ?? nm / pH for acidic and alkaline solutions, respectively. From the characterization results, it was noted that there is an impact of ionic strength and an effect of the temperature of liquid on the response characteristic, which is an advantage of the existing device over the other pH sensors. The fabricated sensor exhibited good reflection spectrum, indicating a blueshift in resonance wavelength for alkaline solutions and a redshift for acidic solutions.

  18. A Review of Distributed Optical Fiber Sensors for Civil Engineering Applications.

    Science.gov (United States)

    Barrias, António; Casas, Joan R; Villalba, Sergi

    2016-05-23

    The application of structural health monitoring (SHM) systems to civil engineering structures has been a developing studied and practiced topic, that has allowed for a better understanding of structures' conditions and increasingly lead to a more cost-effective management of those infrastructures. In this field, the use of fiber optic sensors has been studied, discussed and practiced with encouraging results. The possibility of understanding and monitor the distributed behavior of extensive stretches of critical structures it's an enormous advantage that distributed fiber optic sensing provides to SHM systems. In the past decade, several R & D studies have been performed with the goal of improving the knowledge and developing new techniques associated with the application of distributed optical fiber sensors (DOFS) in order to widen the range of applications of these sensors and also to obtain more correct and reliable data. This paper presents, after a brief introduction to the theoretical background of DOFS, the latest developments related with the improvement of these products by presenting a wide range of laboratory experiments as well as an extended review of their diverse applications in civil engineering structures.

  19. Cartilage microindentation using cylindrical and spherical optical fiber indenters with integrated Bragg gratings as force sensors

    Science.gov (United States)

    Marchi, G.; Canti, O.; Baier, V.; Micallef, W.; Hartmann, B.; Alberton, P.; Aszodi, A.; Clausen-Schaumann, H.; Roths, J.

    2018-02-01

    Fiber optic microindentation sensors that have the potential to be integrated into arthroscopic instruments and to allow localizing degraded articular cartilage are presented in this paper. The indenters consist of optical fibers with integrated Bragg gratings as force sensors. In a basic configuration, the tip of the fiber optic indenter consists of a cleaved fiber end, forming a cylindrical flat punch indenter geometry. When using this indenter geometry, high stresses at the edges of the cylinder are present, which can disrupt the tissue structure. This is avoided with an improved version of the indenter. A spherical indenter tip that is formed by melting the end of the glass fiber. The spherical fiber tip shows the additional advantage of strongly reducing reflections from the fiber end. This allows a reduction of the length of the fiber optic sensor element from 65 mm of the flat punch type to 27 mm of the spherical punch. In order to compare the performance of both indenter types, in vitro stress-relaxation indentation experiments were performed on bovine articular cartilage with both indenter types, to assess biomechanical properties of bovine articular cartilage. For indentation depths between 60 μm and 300 μm, the measurements with both indenter types agreed very well with each other. This shows that both indenter geometries are suitable for microindentation measuremnts . The spherical indenter however has the additional advantage that it minimizes the risk to damage the surface of the tissue and has less than half dimensions than the flat indenter.

  20. Optical fiber sensors-based temperature distribution measurement in ex vivo radiofrequency ablation with submillimeter resolution.

    Science.gov (United States)

    Macchi, Edoardo Gino; Tosi, Daniele; Braschi, Giovanni; Gallati, Mario; Cigada, Alfredo; Busca, Giorgio; Lewis, Elfed

    2014-01-01

    Radiofrequency thermal ablation (RFTA) induces a high-temperature field in a biological tissue having steep spatial (up to 6°C∕mm) and temporal (up to 1°C∕s) gradients. Applied in cancer care, RFTA produces a localized heating, cytotoxic for tumor cells, and is able to treat tumors with sizes up to 3 to 5 cm in diameter. The online measurement of temperature distribution at the RFTA point of care has been previously carried out with miniature thermocouples and optical fiber sensors, which exhibit problems of size, alteration of RFTA pattern, hysteresis, and sensor density worse than 1 sensor∕cm. In this work, we apply a distributed temperature sensor (DTS) with a submillimeter spatial resolution for the monitoring of RFTA in porcine liver tissue. The DTS demodulates the chaotic Rayleigh backscattering pattern with an interferometric setup to obtain the real-time temperature distribution. A measurement chamber has been set up with the fiber crossing the tissue along different diameters. Several experiments have been carried out measuring the space-time evolution of temperature during RFTA. The present work showcases the temperature monitoring in RFTA with an unprecedented spatial resolution and is exportable to in vivo measurement; the acquired data can be particularly useful for the validation of RFTA computational models.

  1. Embedded Distributed Optical Fiber Sensors in Reinforced Concrete Structures—A Case Study

    Science.gov (United States)

    Villalba, Sergi

    2018-01-01

    When using distributed optical fiber sensors (DOFS) on reinforced concrete structures, a compromise must be achieved between the protection requirements and robustness of the sensor deployment and the accuracy of the measurements both in the uncracked and cracked stages and under loading, unloading and reloading processes. With this in mind the authors have carried out an experiment where polyimide-coated DOFS were installed on two concrete beams, both embedded in the rebar elements and also bonded to the concrete surface. The specimens were subjected to a three-point load test where after cracking, they are unloaded and reloaded again to assess the capability of the sensor when applied to a real loading scenarios in concrete structures. Rayleigh Optical Frequency Domain Reflectometry (OFDR) was used as the most suitable technique for crack detection in reinforced concrete elements. To verify the reliability and accuracy of the DOFS measurements, additional strain gauges were also installed at three locations along the rebar. The results show the feasibility of using a thin coated polyimide DOFS directly bonded on the reinforcing bar without the need of indention or mechanization. A proposal for a Spectral Shift Quality (SSQ) threshold is also obtained and proposed for future works when using polyimide-coated DOFS bonded to rebars with cyanoacrylate adhesive. PMID:29587449

  2. Wearable sensors in intelligent clothing for measuring human body temperature based on optical fiber Bragg grating.

    Science.gov (United States)

    Li, Hongqiang; Yang, Haijing; Li, Enbang; Liu, Zhihui; Wei, Kejia

    2012-05-21

    Measuring body temperature is considerably important to physiological studies as well as clinical investigations. In recent years, numerous observations have been reported and various methods of measurement have been employed. The present paper introduces a novel wearable sensor in intelligent clothing for human body temperature measurement. The objective is the integration of optical fiber Bragg grating (FBG)-based sensors into functional textiles to extend the capabilities of wearable solutions for body temperature monitoring. In addition, the temperature sensitivity is 150 pm/°C, which is almost 15 times higher than that of a bare FBG. This study combines large and small pipes during fabrication to implant FBG sensors into the fabric. The law of energy conservation of the human body is considered in determining heat transfer between the body and its clothing. The mathematical model of heat transmission between the body and clothed FBG sensors is studied, and the steady-state thermal analysis is presented. The simulation results show the capability of the material to correct the actual body temperature. Based on the skin temperature obtained by the weighted average method, this paper presents the five points weighted coefficients model using both sides of the chest, armpits, and the upper back for the intelligent clothing. The weighted coefficients of 0.0826 for the left chest, 0.3706 for the left armpit, 0.3706 for the right armpit, 0.0936 for the upper back, and 0.0826 for the right chest were obtained using Cramer's Rule. Using the weighting coefficient, the deviation of the experimental result was ± 0.18 °C, which favors the use for clinical armpit temperature monitoring. Moreover, in special cases when several FBG sensors are broken, the weighted coefficients of the other sensors could be changed to obtain accurate body temperature.

  3. Development of self-sensing BFRP bars with distributed optic fiber sensors

    Science.gov (United States)

    Tang, Yongsheng; Wu, Zhishen; Yang, Caiqian; Shen, Sheng; Wu, Gang; Hong, Wan

    2009-03-01

    In this paper, a new type of self-sensing basalt fiber reinforced polymer (BFRP) bars is developed with using the Brillouin scattering-based distributed optic fiber sensing technique. During the fabrication, optic fiber without buffer and sheath as a core is firstly reinforced through braiding around mechanically dry continuous basalt fiber sheath in order to survive the pulling-shoving process of manufacturing the BFRP bars. The optic fiber with dry basalt fiber sheath as a core embedded further in the BFRP bars will be impregnated well with epoxy resin during the pulling-shoving process. The bond between the optic fiber and the basalt fiber sheath as well as between the basalt fiber sheath and the FRP bar can be controlled and ensured. Therefore, the measuring error due to the slippage between the optic fiber core and the coating can be improved. Moreover, epoxy resin of the segments, where the connection of optic fibers will be performed, is uncured by isolating heat from these parts of the bar during the manufacture. Consequently, the optic fiber in these segments of the bar can be easily taken out, and the connection between optic fibers can be smoothly carried out. Finally, a series of experiments are performed to study the sensing and mechanical properties of the propose BFRP bars. The experimental results show that the self-sensing BFRP bar is characterized by not only excellent accuracy, repeatability and linearity for strain measuring but also good mechanical property.

  4. An optical fiber sensor for hydrocarbons detection in pipelines; Sensor a fibra otica para deteccao de hidrocarbonetos em oleodutos

    Energy Technology Data Exchange (ETDEWEB)

    Klemba, Francelli; Kamikawachi, Ricardo Canute; Mueller, Marcia; Kalinowski, Hypolito Jose; Fabris, Jose Luis [Centro Federal de Educacao Tecnologica do Parana (CEFET-PR), Curitiba, PR (Brazil)

    2004-07-01

    In this work we describe the use of long period gratings in optical fibers as a sensor device in the detection of hydrocarbons that flow in pipelines. In the experiments samples of alcohol, gasoline, turpentine, thinner, kerosene and diesel were used. Due to the different refractive index of these substances there was a shift in the wavelength of the attenuation peak of the grating, which initially in the air was 1544 nm, allowing the construction and calibration of a sensor device. The response time of the sensor was 3 seconds for the different samples used. The long period grating was produced through the technique of electric arc discharge with the aid of a fusion splicer machine. (author)

  5. Hydrogen peroxide and glucose concentration measurement using optical fiber grating sensors with corrodible plasmonic nanocoatings.

    Science.gov (United States)

    Zhang, Xuejun; Wu, Ze; Liu, Fu; Fu, Qiangqiang; Chen, Xiaoyong; Xu, Jian; Zhang, Zhaochuan; Huang, Yunyun; Tang, Yong; Guo, Tuan; Albert, Jacques

    2018-04-01

    We propose and demonstrate hydrogen peroxide (H 2 O 2 ) and glucose concentration measurements using a plasmonic optical fiber sensor. The sensor utilizes a tilted fiber Bragg grating (TFBG) written in standard single mode communication fiber. The fiber is over coated with an nm-scale film of silver that supports surface plasmon resonances (SPRs). Such a tilted grating SPR structure provides a high density of narrow spectral resonances (Q-factor about 10 5 ) that overlap with the broader absorption band of the surface plasmon waves in the silver film, thereby providing an accurate tool to measure small shifts of the plasmon resonance frequencies. The H 2 O 2 to be detected acts as an oxidant to etch the silver film, which has the effect of gradually decreasing the SPR attenuation. The etching rate of the silver film shows a clear relationship with the H 2 O 2 concentration so that monitoring the progressively increasing attenuation of a selected surface plasmon resonance over a few minutes enables us to measure the H 2 O 2 concentration with a limit of detection of 0.2 μM. Furthermore, the proposed method can be applied to the determination of glucose in human serum for a concentration range from 0 to 12 mM (within the physiological range of 3-8 mM) by monitoring the H 2 O 2 produced by an enzymatic oxidation process. The sensor does not require accurate temperature control because of the inherent temperature insensitivity of TFBG devices referenced to the core mode resonance. A gold mirror coated on the fiber allows the sensor to work in reflection, which will facilitate the integration of the sensor with a hypodermic needle for in vitro measurements. The present study shows that Ag-coated TFBG-SPR can be applied as a promising type of sensing probe for optical detection of H 2 O 2 and glucose detection in human serum.

  6. Temperature Compensation in Determining of Remazol Black B Concentrations Using Plastic Optical Fiber Based Sensor

    Science.gov (United States)

    Chong, Su Sin; Aziz, A.R. Abdul; Harun, Sulaiman W.; Arof, Hamzah

    2014-01-01

    In this study, the construction and test of tapered plastic optical fiber (POF) sensors, based on an intensity modulation approach are described. Tapered fiber sensors with different diameters of 0.65 mm, 0.45 mm, and 0.35 mm, were used to measure various concentrations of Remazol black B (RBB) dye aqueous solutions at room temperature. The concentrations of the RBB solutions were varied from 0 ppm to 70 ppm. In addition, the effect of varying the temperature of the RBB solution was also investigated. In this case, the output of the sensor was measured at four different temperatures of 27 °C, 30 °C, 35 °C, and 40 °C, while its concentration was fixed at 50 ppm and 100 ppm. The experimental results show that the tapered POF with d = 0.45 mm achieves the best performance with a reasonably good sensitivity of 61 × 10−4 and a linearity of more than 99%. It also maintains a sufficient and stable signal when heat was applied to the solution with a linearity of more than 97%. Since the transmitted intensity is dependent on both the concentration and temperature of the analyte, multiple linear regression analysis was performed to combine the two independent variables into a single equation. The resulting equation was then validated experimentally and the best agreement between the calculated and experimental results was achieved by the sensor with d = 0.45 mm, where the minimum discrepancy is less than 5%. The authors conclude that POF-based sensors are suitable for RBB dye concentration sensing and, with refinement in fabrication, better results could be achieved. Their low fabrication cost, simple configuration, accuracy, and high sensitivity would attract many potential applications in chemical and biological sensing. PMID:25166498

  7. Temperature Compensation in Determining of Remazol Black B Concentrations Using Plastic Optical Fiber Based Sensor

    Directory of Open Access Journals (Sweden)

    Su Sin Chong

    2014-08-01

    Full Text Available In this study, the construction and test of tapered plastic optical fiber (POF sensors, based on an intensity modulation approach are described. Tapered fiber sensors with different diameters of 0.65 mm, 0.45 mm, and 0.35 mm, were used to measure various concentrations of Remazol black B (RBB dye aqueous solutions at room temperature. The concentrations of the RBB solutions were varied from 0 ppm to 70 ppm. In addition, the effect of varying the temperature of the RBB solution was also investigated. In this case, the output of the sensor was measured at four different temperatures of 27 °C, 30 °C, 35 °C, and 40 °C, while its concentration was fixed at 50 ppm and 100 ppm. The experimental results show that the tapered POF with d = 0.45 mm achieves the best performance with a reasonably good sensitivity of 61 × 10−4 and a linearity of more than 99%. It also maintains a sufficient and stable signal when heat was applied to the solution with a linearity of more than 97%. Since the transmitted intensity is dependent on both the concentration and temperature of the analyte, multiple linear regression analysis was performed to combine the two independent variables into a single equation. The resulting equation was then validated experimentally and the best agreement between the calculated and experimental results was achieved by the sensor with d = 0.45 mm, where the minimum discrepancy is less than 5%. The authors conclude that POF-based sensors are suitable for RBB dye concentration sensing and, with refinement in fabrication, better results could be achieved. Their low fabrication cost, simple configuration, accuracy, and high sensitivity would attract many potential applications in chemical and biological sensing.

  8. Hydrogen peroxide and glucose concentration measurement using optical fiber grating sensors with corrodible plasmonic nanocoatings

    Science.gov (United States)

    Zhang, Xuejun; Wu, Ze; Liu, Fu; Fu, Qiangqiang; Chen, Xiaoyong; Xu, Jian; Zhang, Zhaochuan; Huang, Yunyun; Tang, Yong; Guo, Tuan; Albert, Jacques

    2018-01-01

    We propose and demonstrate hydrogen peroxide (H2O2) and glucose concentration measurements using a plasmonic optical fiber sensor. The sensor utilizes a tilted fiber Bragg grating (TFBG) written in standard single mode communication fiber. The fiber is over coated with an nm-scale film of silver that supports surface plasmon resonances (SPRs). Such a tilted grating SPR structure provides a high density of narrow spectral resonances (Q-factor about 105) that overlap with the broader absorption band of the surface plasmon waves in the silver film, thereby providing an accurate tool to measure small shifts of the plasmon resonance frequencies. The H2O2 to be detected acts as an oxidant to etch the silver film, which has the effect of gradually decreasing the SPR attenuation. The etching rate of the silver film shows a clear relationship with the H2O2 concentration so that monitoring the progressively increasing attenuation of a selected surface plasmon resonance over a few minutes enables us to measure the H2O2 concentration with a limit of detection of 0.2 μM. Furthermore, the proposed method can be applied to the determination of glucose in human serum for a concentration range from 0 to 12 mM (within the physiological range of 3-8 mM) by monitoring the H2O2 produced by an enzymatic oxidation process. The sensor does not require accurate temperature control because of the inherent temperature insensitivity of TFBG devices referenced to the core mode resonance. A gold mirror coated on the fiber allows the sensor to work in reflection, which will facilitate the integration of the sensor with a hypodermic needle for in vitro measurements. The present study shows that Ag-coated TFBG-SPR can be applied as a promising type of sensing probe for optical detection of H2O2 and glucose detection in human serum. PMID:29675315

  9. Simultaneous remote measurement of CO2 concentration, humidity and temperature with a matrix of optical fiber sensors

    Science.gov (United States)

    Wysokiński, Karol; Filipowicz, Marta; Stańczyk, Tomasz; Lipiński, Stanisław; Napierała, Marek; Murawski, Michał; Nasiłowski, Tomasz

    2017-10-01

    A matrix of optical fiber sensors eligible for remote measurements is reported in this paper. The aim of work was to monitor the air quality with a device, which does not need any electricity on site of the measurement. The matrix consists of several sensors detecting carbon dioxide concentration, relative humidity and temperature. Sensors utilize active optical materials, which change their color when exposed to varied conditions. All the sensors are powered with standard light emitting diodes. Light is transmitted by an optical fiber from the light source and then it reaches the active layer which changes its color, when the conditions change. This results in a change of attenuation of light passing through the active layer. Modified light is then transmitted by another optical fiber to the detector, where simple photoresistor is used. It is powered by a stabilized DC power supply and the current is measured. Since no expensive elements are needed to manufacture such a matrix of sensors, its price may be competitive to the price of the devices already available on the market, while the matrix also exhibits other valuable properties.

  10. Cost-effective optical fiber pressure sensor based on intrinsic Fabry-Perot interferometric micro-cavities

    Science.gov (United States)

    Domingues, M. Fátima; Rodriguez, Camilo A.; Martins, Joana; Tavares, Cátia; Marques, Carlos; Alberto, Nélia; André, Paulo; Antunes, Paulo

    2018-05-01

    In this work, a cost-effective procedure to manufacture optical fiber pressure sensors is presented. This has a high relevance for integration in robotic exoskeletons or for gait plantar pressure monitoring within the physical rehabilitation scenarios, among other applications. The sensing elements are based on Fabry-Perot interferometric (FPI) micro-cavities, created from the recycling of optical fibers previously destroyed by the catastrophic fuse effect. To produce the pressure sensors, the fiber containing the FPI micro-cavities was embedded in an epoxy resin cylinder used as pressure transducer and responsible to transfer the pressure applied on its surface to the optical fiber containing the FPI micro-cavity. Before the embedding process, some FPI sensors were also characterized to strain variations. After that, the effect of the encapsulation of the FPI structure into the resin was assessed, from which a slight decrease on the FPI interferogram fringes visibility was verified, indicating a small increase in the micro-cavity length. Up on the sensors characterization, a linear dependence of the wavelength shift with the induced pressure was obtained, which leads to a maximum sensitivity of 59.39 ± 1.7 pm/kPa. Moreover, direct dependence of the pressure sensitivity with the micro-cavity volume and length was found.

  11. Extrinsic optical-fiber ultrasound sensor using a thin polymer film as a low-finesse Fabry-Perot interferometer

    Science.gov (United States)

    Beard, P. C.; Mills, T. N.

    1996-02-01

    Theoretical and experimental aspects of an extrinsic optical-fiber ultrasound sensor are described. The sensor is based on a thin transparent polymer film acting as a low-finesse Fabry-Perot cavity that is mounted at the end of a multimode optical fiber. Performance was found to be comparable with that of a piezoelectric polyvinylidene difluoride-membrane (PVDF) hydrophone with a sensitivity of 61 mV/MPa, an acoustic noise floor of 2.3 KPa over a 25-MHz bandwidth, and a frequency response to 25 MHz. The wideband-sensitive response and design flexibility of the concept suggests that it may find application as an alternative to piezoelectric devices for the detection and measurement of ultrasound.

  12. Enhancement of the sensitivity of gas sensor based on microstructure optical fiber

    Science.gov (United States)

    Morshed, Monir; Hasan, Md. Imran; Razzak, S. M. Abdur

    2015-12-01

    This paper proposes the design and characterization of microstructure optical fiber for gas sensing applications. The aim is to detect toxic and colorless gases over a wide transmission band covering 0.80 µm to 2.00 µm wavelength. Numerical investigation is carried out by using the finite element method (FEM). The numerical study shows that sensitivity of the proposed sensor is moderately increased by introducing four non-circular holes around the defected core of photonic crystal fiber and the confinement loss is also reduced. Furthermore, we confirm that increasing the diameter of central air core and size of the non-circular holes can improve the relative sensitivity and the confinement loss is reduced by increasing the diameter of air holes in the cladding. The enhancement of the relative sensitivity is more than 27.58% (0.1323 to 0.1688) at the wavelength λ=1.33µm that is the absorption line of methane (CH4) and hydrogen fluoride (HF) gases. The confinement loss of the fiber is 1.765×10-8 dB/m.

  13. Progress in miniaturization of a multichannel optical fiber Bragg grating sensor interrogator

    Science.gov (United States)

    Lopatin, Craig M.; Mahmood, Shah; Mendoza, Edgar; Moslehi, Behzad; Black, Richard; Chau, Kelvin; Oblea, Levy

    2007-07-01

    An effort to develop a miniaturized multichannel optical fiber Bragg grating sensor interrogator was initiated in 2006 under the Small Business Innovative Research (SBIR) program. The goal was to develop an interrogator that would be sufficiently small and light to be incorporated into a health monitoring system for use on tactical missiles. Two companies, Intelligent Fiber Optic Systems Corporation (IFOS) and Redondo Optics, were funded in Phase I, and this paper describes the prototype interrogators that were developed. The two companies took very different approaches: IFOS focused on developing a unit that would have a high channel count and high resolution, using off-the-shelf components, while Redondo Optics chose to develop a unit that would be very small and lightweight, using custom designed integrated optical chips. It is believed that both approaches will result in interrogators that will be significantly small, lighter, and possibly even more precise than what is currently commercially available. This paper will also briefly describe some of the sensing concepts that may be used to interrogate the health of the solid rocket motors used in many missile systems. The sponsor of this program was NAVAIR PMA 280.

  14. Insole optical fiber Bragg grating sensors network for dynamic vertical force monitoring.

    Science.gov (United States)

    Domingues, Maria Fátima; Tavares, Cátia; Leitão, Cátia; Frizera-Neto, Anselmo; Alberto, Nélia; Marques, Carlos; Radwan, Ayman; Rodriguez, Jonathan; Postolache, Octavian; Rocon, Eduardo; André, Paulo; Antunes, Paulo

    2017-09-01

    In an era of unprecedented progress in technology and increase in population age, continuous and close monitoring of elder citizens and patients is becoming more of a necessity than a luxury. Contributing toward this field and enhancing the life quality of elder citizens and patients with disabilities, this work presents the design and implementation of a noninvasive platform and insole fiber Bragg grating sensors network to monitor the vertical ground reaction forces distribution induced in the foot plantar surface during gait and body center of mass displacements. The acquired measurements are a reliable indication of the accuracy and consistency of the proposed solution in monitoring and mapping the vertical forces active on the foot plantar sole, with a sensitivity up to 11.06 ?? pm / N . The acquired measurements can be used to infer the foot structure and health condition, in addition to anomalies related to spine function and other pathologies (e.g., related to diabetes); also its application in rehabilitation robotics field can dramatically reduce the computational burden of exoskeletons’ control strategy. The proposed technology has the advantages of optical fiber sensing (robustness, noninvasiveness, accuracy, and electromagnetic insensitivity) to surpass all drawbacks verified in traditionally used sensing systems (fragility, instability, and inconsistent feedback).

  15. Insole optical fiber Bragg grating sensors network for dynamic vertical force monitoring

    Science.gov (United States)

    Domingues, Maria Fátima; Tavares, Cátia; Leitão, Cátia; Frizera-Neto, Anselmo; Alberto, Nélia; Marques, Carlos; Radwan, Ayman; Rodriguez, Jonathan; Postolache, Octavian; Rocon, Eduardo; André, Paulo; Antunes, Paulo

    2017-09-01

    In an era of unprecedented progress in technology and increase in population age, continuous and close monitoring of elder citizens and patients is becoming more of a necessity than a luxury. Contributing toward this field and enhancing the life quality of elder citizens and patients with disabilities, this work presents the design and implementation of a noninvasive platform and insole fiber Bragg grating sensors network to monitor the vertical ground reaction forces distribution induced in the foot plantar surface during gait and body center of mass displacements. The acquired measurements are a reliable indication of the accuracy and consistency of the proposed solution in monitoring and mapping the vertical forces active on the foot plantar sole, with a sensitivity up to 11.06 pm/N. The acquired measurements can be used to infer the foot structure and health condition, in addition to anomalies related to spine function and other pathologies (e.g., related to diabetes); also its application in rehabilitation robotics field can dramatically reduce the computational burden of exoskeletons' control strategy. The proposed technology has the advantages of optical fiber sensing (robustness, noninvasiveness, accuracy, and electromagnetic insensitivity) to surpass all drawbacks verified in traditionally used sensing systems (fragility, instability, and inconsistent feedback).

  16. A Linear Birefringence Measurement Method for an Optical Fiber Current Sensor.

    Science.gov (United States)

    Xu, Shaoyi; Shao, Haiming; Li, Chuansheng; Xing, Fangfang; Wang, Yuqiao; Li, Wei

    2017-07-03

    In this work, a linear birefringence measurement method is proposed for an optical fiber current sensor (OFCS). First, the optical configuration of the measurement system is presented. Then, the elimination method of the effect of the azimuth angles between the sensing fiber and the two polarizers is demonstrated. Moreover, the relationship of the linear birefringence, the Faraday rotation angle and the final output is determined. On these bases, the multi-valued problem on the linear birefringence is simulated and its solution is illustrated when the linear birefringence is unknown. Finally, the experiments are conducted to prove the feasibility of the proposed method. When the numbers of turns of the sensing fiber in the OFCS are about 15, 19, 23, 27, 31, 35, and 39, the measured linear birefringence obtained by the proposed method are about 1.3577, 1.8425, 2.0983, 2.5914, 2.7891, 3.2003 and 3.5198 rad. Two typical methods provide the references for the proposed method. The proposed method is proven to be suitable for the linear birefringence measurement in the full range without the limitation that the linear birefringence must be smaller than π/2.

  17. Design and realization of temperature measurement system based on optical fiber temperature sensor for wireless power transfer

    Science.gov (United States)

    Chen, Xi; Zeng, Shuang; Liu, Xiulan; Jin, Yuan; Li, Xianglong; Wang, Xiaochen

    2018-02-01

    The electric vehicles (EV) have become accepted by increasing numbers of people for the environmental-friendly advantages. A novel way to charge the electric vehicles is through wireless power transfer (WPT). The wireless power transfer is a high power transfer system. The high currents flowing through the transmitter and receiver coils increasing temperature affects the safety of person and charging equipment. As a result, temperature measurement for wireless power transfer is needed. In this paper, a temperature measurement system based on optical fiber temperature sensors for electric vehicle wireless power transfer is proposed. Initially, the thermal characteristics of the wireless power transfer system are studied and the advantages of optical fiber sensors are analyzed. Then the temperature measurement system based on optical fiber temperature sensor is designed. The system consists of optical subsystem, data acquisition subsystem and data processing subsystem. Finally, the system is tested and the experiment result shows that the system can realize 1°C precision and can acquire real-time temperature distribution of the coils, which can meet the requirement of the temperature measuring for wireless power transfer.

  18. Realization of rapid debugging for detection circuit of optical fiber gas sensor: Using an analog signal source

    Science.gov (United States)

    Tian, Changbin; Chang, Jun; Wang, Qiang; Wei, Wei; Zhu, Cunguang

    2015-03-01

    An optical fiber gas sensor mainly consists of two parts: optical part and detection circuit. In the debugging for the detection circuit, the optical part usually serves as a signal source. However, in the debugging condition, the optical part can be easily influenced by many factors, such as the fluctuation of ambient temperature or driving current resulting in instability of the wavelength and intensity for the laser; for dual-beam sensor, the different bends and stresses of the optical fiber will lead to the fluctuation of the intensity and phase; the intensity noise from the collimator, coupler, and other optical devices in the system will also result in the impurity of the optical part based signal source. In order to dramatically improve the debugging efficiency of the detection circuit and shorten the period of research and development, this paper describes an analog signal source, consisting of a single chip microcomputer (SCM), an amplifier circuit, and a voltage-to-current conversion circuit. It can be used to realize the rapid debugging detection circuit of the optical fiber gas sensor instead of optical part based signal source. This analog signal source performs well with many other advantages, such as the simple operation, small size, and light weight.

  19. Metal-Organic Framework Thin Film Coated Optical Fiber Sensors: A Novel Waveguide-Based Chemical Sensing Platform.

    Science.gov (United States)

    Kim, Ki-Joong; Lu, Ping; Culp, Jeffrey T; Ohodnicki, Paul R

    2018-02-23

    Integration of optical fiber with sensitive thin films offers great potential for the realization of novel chemical sensing platforms. In this study, we present a simple design strategy and high performance of nanoporous metal-organic framework (MOF) based optical gas sensors, which enables detection of a wide range of concentrations of small molecules based upon extremely small differences in refractive indices as a function of analyte adsorption within the MOF framework. Thin and compact MOF films can be uniformly formed and tightly bound on the surface of etched optical fiber through a simple solution method which is critical for manufacturability of MOF-based sensor devices. The resulting sensors show high sensitivity/selectivity to CO 2 gas relative to other small gases (H 2 , N 2 , O 2 , and CO) with rapid (optical fiber platform which results in an amplification of inherent optical absorption present within the MOF-based sensing layer with increasing values of effective refractive index associated with adsorption of gases.

  20. Optical fiber taste sensors using potential sensitive dye coatings. Makuden'i kanjusei shikisomaku wo mochiita hikari fiber mikaku sensor

    Energy Technology Data Exchange (ETDEWEB)

    Yamakawa, S.; Yamaguchi, A. (Toyama National College of Maritime Technology, Toyama (Japan))

    1992-12-20

    The present paper proposes a new taste recognition system using optical response patterns from multi-channel optical fiber sensors having potential sensitive dye coatings. It was found that the sensors give large changes in optical absorption spectra of the dyes when they are immersed in various taste solutions. Consequently, it was shown that the sensors can be used as a taste sensor. Six dyes, which give large changes in dye absorption, were selected from twenty dyes and used for six-channel optical fiber taste sensors array. The absorption spectra change data were processed by multiple discriminant analysis and neural networks using back-propagation algorithm. From the analytical results, it was demonstrated that salty (NaCl), bitter (quinidine), sweet (sucrose), sour (HCl), and umami (sodium glutamate) substances can be recognized from each other by using the optical taste sensor system. 11 refs., 8 figs., 2 tabs.

  1. An Optical Fiber-Based Sensor Array for the Monitoring of Zinc and Copper Ions in Aqueous Environments

    Directory of Open Access Journals (Sweden)

    Steven Kopitzke

    2014-02-01

    Full Text Available Copper and zinc are elements commonly used in industrial applications as aqueous solutions. Before the solutions can be discharged into civil or native waterways, waste treatment processes must be undertaken to ensure compliance with government guidelines restricting the concentration of ions discharged in solution. While currently there are methods of analysis available to monitor these solutions, each method has disadvantages, be it high costs, inaccuracy, and/or being time-consuming. In this work, a new optical fiber-based platform capable of providing fast and accurate results when performing solution analysis for these metals is described. Fluorescent compounds that exhibit a high sensitivity and selectivity for either zinc or copper have been employed for fabricating the sensors. These sensors demonstrated sub-part-per-million detection limits, 30-second response times, and the ability to analyze samples with an average error of under 10%. The inclusion of a fluorescent compound as a reference material to compensate for fluctuations from pulsed excitation sources has further increased the reliability and accuracy of each sensor. Finally, after developing sensors capable of monitoring zinc and copper individually, these sensors are combined to form a single optical fiber sensor array capable of simultaneously monitoring concentration changes in zinc and copper in aqueous environments.

  2. Fiber Optic Sensors for Health Monitoring of Morphing Airframes. Part 2; Chemical Sensing Using Optical Fibers with Bragg Gratings

    Science.gov (United States)

    Wood, Karen; Brown, Timothy; Rogowski, Robert; Jensen, Brian

    2000-01-01

    Part 1 of this two part series described the fabrication and calibration of Bragg gratings written into a single mode optical fiber for use in strain and temperature monitoring. Part 2 of the series describes the use of identical fibers and additional multimode fibers, both with and without Bragg gratings, to perform near infrared spectroscopy. The demodulation system being developed at NASA Langley Research Center currently requires the use of a single mode optical fiber. Attempts to use this single mode fiber for spectroscopic analysis are problematic given its small core diameter, resulting in low signal intensity. Nonetheless, we have conducted a preliminary investigation using a single mode fiber in conjunction with an infrared spectrometer to obtain spectra of a high-performance epoxy resin system. Spectra were obtained using single mode fibers that contained Bragg gratings; however, the peaks of interest were barely discernible above the noise. The goal of this research is to provide a multipurpose sensor in a single optical fiber capable of measuring a variety of chemical and physical properties.

  3. A packaged, low-cost, robust optical fiber strain sensor based on small cladding fiber sandwiched within periodic polymer grating.

    Science.gov (United States)

    Chiang, Chia-Chin; Li, Chein-Hsing

    2014-06-02

    In the present study, a novel packaged long-period fiber grating (PLPFG) strain sensor is first presented. The MEMS process was utilized to fabricate the packaged optical fiber strain sensor. The sensor structure consisted of etched optical fiber sandwiched between two layers of thick photoresist SU-8 3050 and then packaged with poly (dimethylsiloxane) (PDMS) polymer material to construct the PLPFG strain sensor. The PDMS packaging material was used to prevent the glue effect, wherein glue flows into the LPFG structure and reduces coupling strength, in the surface bonding process. Because the fiber grating was packaged with PDMS material, it was effectively protected and made robust. The resonance attenuation dip of PLPFG grows when it is loading. This study explored the size effect of the grating period and fiber diameter of PLPFG via tensile testing. The experimental results found that the best strain sensitivity of the PLPFG strain sensor was -0.0342 dB/με, and that an R2 value of 0.963 was reached.

  4. Novel Modified Optical Fibers for High Temperature In-Situ Miniaturized Gas Sensors in Advanced Fossil Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Pickrell, Gary [Virginia Polytechnic Institute & State University, Blacksburg, VA (United States); Scott, Brian [Virginia Polytechnic Institute & State University, Blacksburg, VA (United States)

    2014-06-30

    This report covers the technical progress on the program “Novel Modified Optical Fibers for High Temperature In-Situ Miniaturized Gas Sensors in Advanced Fossil Energy Systems”, funded by the National Energy Technology Laboratory of the U.S. Department of Energy, and performed by the Materials Science & Engineering and Electrical & Computer Engineering Departments at Virginia Tech, and summarizes technical progress from July 1st, 2005 –June 30th, 2014. The objective of this program was to develop novel fiber materials for high temperature gas sensors based on evanescent wave absorption in optical fibers. This project focused on two primary areas: the study of a sapphire photonic crystal fiber (SPCF) for operation at high temperature and long wavelengths, and a porous glass based fiber optic sensor for gas detection. The sapphire component of the project focused on the development of a sapphire photonic crystal fiber, modeling of the new structures, fabrication of the optimal structure, development of a long wavelength interrogation system, testing of the optical properties, and gas and temperature testing of the final sensor. The fabrication of the 6 rod SPCF gap bundle (diameter of 70μm) with a hollow core was successfully constructed with lead-in and lead-out 50μm diameter fiber along with transmission and gas detection testing. Testing of the sapphire photonic crystal fiber sensor capabilities with the developed long wavelength optical system showed the ability to detect CO2 at or below 1000ppm at temperatures up to 1000°C. Work on the porous glass sensor focused on the development of a porous clad solid core optical fiber, a hollow core waveguide, gas detection capabilities at room and high temperature, simultaneous gas species detection, suitable joining technologies for the lead-in and lead-out fibers and the porous sensor, sensor system sensitivity improvement, signal processing improvement, relationship between pore structure and fiber

  5. Laser of optical fiber composed by two coupled cavities: application as optical fiber sensor; Laser de fibra optica compuesto por dos cavidades acopladas: aplicacion como sensor de fibra optica

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez S, R.A.; Kuzin, E.A.; Ibarra E, B. [Instituto Nacional de Astrofisica, Optica y Electronica (INAOE), A.P. 51 y 216, 72000 Puebla (Mexico); May A, M. [Universidad Autonoma del Carmen (UNACAR) Av. 56 No. 4 por Av. Concordia, Campeche (Mexico); Shlyagin, M.; Marquez B, I. [Centro de Investigacion Cientifica y de Ensenanza Superior de Ensenada (CICESE), 22860 Ensenada, Baja California (Mexico)]. e-mail: ravsa100@hotmail.com

    2004-07-01

    We show an optical fiber laser sensor which consist of two cavities coupled and three fiber Bragg gratings. We used one Bragg grating (called reference) and two Bragg gratings (called sensors), which have the lower reflection wavelength. The reference grating with the two sensors grating make two cavities: first one is the internal cavity which has 4230 m of length and the another one is the external cavity which has 4277 m of length. Measuring the laser beating frequency for a resonance cavity and moving the frequency peaks when the another cavity is put in resonance, we prove that the arrangement can be used as a two points sensor for determining the difference of temperature or stress between these two points. (Author)

  6. Temperature insensitive hysteresis free highly sensitive polymer optical fiber Bragg grating humidity sensor

    DEFF Research Database (Denmark)

    Woyessa, Getinet; Nielsen, Kristian; Stefani, Alessio

    2016-01-01

    The effect of humidity on annealing of poly (methyl methacrylate) (PMMA) based microstructured polymer optical fiber Bragg gratings (mPOFBGs) and the resulting humidity responsivity are investigated. Typically annealing of PMMA POFs is done in an oven without humidity control around 80°C...

  7. Aspects of optical fibers and spectrometric sensors in chemical process and industrial environments

    International Nuclear Information System (INIS)

    Boisde, G.; Perez, J.J.

    1988-01-01

    For on-line control, the two alternatives of automatic sample transfer and in situ remote analysis are discussed. New concepts are emerging from the possibilities offered by optical fibers. Absorption in the visible, UV and IR, fluorescence and Raman spectrometric techniques are examined. The state of the art of optodes and devices in chemical process control are given, with some examples of applications in nuclear plants

  8. Research on dual-parameter optical fiber sensor based on thin-core fiber and spherical structure

    Science.gov (United States)

    Tong, Zhengrong; Wang, Xue; Zhang, Weihua; Xue, Lifang

    2018-04-01

    A novel dual-parameter optical fiber sensor is proposed and experimentally demonstrated. The proposed sensor is based on a fiber in-line Mach-Zehnder interferometer, which is fabricated by sandwiching a section of thin-core fiber between two spherical structures made of single-mode fibers. The transmission spectrum exhibits the response of the interference between the core and the different cladding modes. Due to the different wavelength shifts of the two selected dips, the simultaneous measurement of temperature and the surrounding refractive index can be achieved. The measured temperature sensitivities are 0.067 nm/°C and 0.050 nm/°C, and the refractive index sensitivities are  -119.9 nm/RIU and  -69.71 nm/RIU, respectively. In addition, the compact size, simple fabrication and cost-effectiveness of the fiber sensor are also advantages.

  9. Long-term strain response of polymer optical fiber FBG sensors

    DEFF Research Database (Denmark)

    Bundalo, Ivan-Lazar; Nielsen, Kristian; Woyessa, Getinet

    2017-01-01

    We report on the viscoelastic response of PMMA microstructured polymer optical fibers (mPOFs) when exposed to long periods of strain and relaxation, with the strain period ranging from 0.5 min to 50 min. The behavior of the fibers was monitored by inscribing a fiber Bragg grating (FBG) in them...... and tracking the reflection peak. We demonstrate that the fiber, when relaxing from strains of up to 0.9%, has a two-phase recovery: initially linear (elastic driven) and subsequently nonlinear (viscoelastic driven) contraction. The linear (elastic) relaxation wavelength range depends both on the strain level...

  10. Production and Characterization of Polycarbonate Microstructured Polymer Optical Fiber Bragg Grating Sensor

    DEFF Research Database (Denmark)

    Fasano, Andrea; Woyessa, Getinet; Stajanca, P.

    2015-01-01

    , such as casting of pol-ymer granulates into a solid rod, machining and drilling of a 3-ring hexagonal lattice of holes into it, and finally drawing into fiber. We demonstrate that the obtained PC mPOF is photosensitive and FBGs can be conveniently inscribed into it, thereby enabling FBG-based temperature...... and strain sensing. The PC optical fibers are for some applications an attractive alternative to conventional materials used in POF fabrication, such as polymethyl methacrylate (PMMA). In general, PC can be used at temperature up to 120 °C and breaks at considerably higher strains than PMMA....

  11. Highly sensitive detection of molecular interactions with plasmonic optical fiber grating sensors.

    Science.gov (United States)

    Voisin, Valérie; Pilate, Julie; Damman, Pascal; Mégret, Patrice; Caucheteur, Christophe

    2014-01-15

    Surface Plasmon resonance (SPR) optical fiber biosensors constitute a miniaturized counterpart to the bulky prism configuration and offer remote operation in very small volumes of analyte. They are a cost-effective and relatively straightforward technique to yield in situ (or even possibly in vivo) molecular detection. The biosensor configuration reported in this work uses nanometric-scale gold-coated tilted fiber Bragg gratings (TFBGs) interrogated by light polarized radially to the optical fiber outer surface, so as to maximize the optical coupling with the SPR. These gratings were recently associated to aptamers to assess their label-free biorecognition capability in buffer and serum solutions. In this work, using the well-acknowledged biotin-streptavidin pair as a benchmark, we go forward in the demonstration of their unique sensitivity. In addition to the monitoring of the self-assembled monolayer (SAM) in real time, we report an unprecedented limit of detection (LOD) as low as 2 pM. Finally, an immunosensing experiment is realized with human transferrin (dissociation constant Kd~10(-8) M(-1)). It allows to assess both the reversibility and the robustness of the SPR-TFBG biosensors and to confirm their high sensitivity. © 2013 Published by Elsevier B.V.

  12. Measurement of Temperature and Relative Humidity with Polymer Optical Fiber Sensors Based on the Induced Stress-Optic Effect

    Science.gov (United States)

    Pontes, Maria José

    2018-01-01

    This paper presents a system capable of measuring temperature and relative humidity with polymer optical fiber (POF) sensors. The sensors are based on variations of the Young’s and shear moduli of the POF with variations in temperature and relative humidity. The system comprises two POFs, each with a predefined torsion stress that resulted in a variation in the fiber refractive index due to the stress-optic effect. Because there is a correlation between stress and material properties, the variation in temperature and humidity causes a variation in the fiber’s stress, which leads to variations in the fiber refractive index. Only two photodiodes comprise the sensor interrogation, resulting in a simple and low-cost system capable of measuring humidity in the range of 5–97% and temperature in the range of 21–46 °C. The root mean squared errors (RMSEs) between the proposed sensors and the reference were 1.12 °C and 1.36% for the measurements of temperature and relative humidity, respectively. In addition, fiber etching resulted in a sensor with a 2 s response time for a relative humidity variation of 10%, which is one of the lowest recorded response times for intrinsic POF humidity sensors. PMID:29558387

  13. Optical fibers and their applications for radiation measurements

    International Nuclear Information System (INIS)

    Kakuta, Tsunemi

    1998-01-01

    As a new method of radiation measurements, several optical methods using optical fiber sensors have been developed. One is the application of 'radio-luminescence' from the optical fiber itself such as plastic scintillating fibers. Other researches are made to develop the 'combined-sensors' by combination of optical fibers and scintillating materials. Using the time domain method of optical fiber sensors, the profile of radiation distribution along the optical fiber can be easily determined. A multi-parameter sensing system for measurement of radiation, temperature, stress, etc, are also expected using these optical fiber sensors. (author)

  14. Temperature-referenced high-sensitivity point-probe optical fiber chem-sensors based on cladding etched fiber Bragg gratings

    OpenAIRE

    Zhou, Kaiming; Chen, Xianfeng F.; Zhang, Lin; Bennion, Ian

    2004-01-01

    Point-probe optical fiber chem-sensors have been implemented using cladding etched fiber Bragg gratings. The sensors possess refractive index sensing capability that can be utilized to measure chemical concentrations. The Bragg wavelength shift reaches 8 nm when the index of surrounding medium changes from 1.33 to 1.44, giving maximum sensitivity more than 10 times higher than that of previously reported devices. More importantly, the dual-grating configuration of the point-probe sensors offe...

  15. The influence of curvature configuration on the characteristic of alcohol gel insertion jacket of polymer optical fiber liquid level sensor

    Science.gov (United States)

    Arumnika, N.; Kuswanto, H.

    2018-04-01

    This study aimed to determine the effect of curvature configuration to sensitivities and linearities of Polymer Optical Fiber (POF) water level sensor. POF type SH-4001-1.3 has been used in this study. The jacket of POF of 20 cm was removed. Transparent piped inserted by alcohol gel has been used to replace the jacket. This is head of a sensor. The head of a sensor is curved with variations of the specified path length, peel length, the width of curvature, the height of curvature and waveform. Configuration A (20 cm, 34 cm, 6 cm, 2 cm, 1 wave), configuration B (20 cm, 34 cm, 8 cm, 2 cm, 1 wave), configuration C (20 cm, 34 cm, 9 cm, 2 cm, ½ wave), configuration D (20 cm, 34 cm, 10 cm, 2 cm, ½ wave). The head of a sensor inserted into the water tank. The light source inserted to one end POF is a He-Ne laser light with a power of 5 mW and a wavelength of 632.8 nm. Power output at the other end received by the Optical Power Meter (OPM). The curvature configuration the head sensor of POF affects the output. Configuration A has good sensitivity, however good linearity given by configuration.

  16. Refractometers for different refractive index range by surface plasmon resonance sensors in multimode optical fibers with different metals

    Science.gov (United States)

    Zuppella, P.; Corso, Alain J.; Pelizzo, Maria G.; Cennamo, N.; Zeni, L.

    2016-09-01

    We have realized a plasmonic sensor based on Au/Pd metal bilayer in a multimode plastic optical fiber. This metal bilayer, based on a metal with high imaginary part of the refractive index and gold, shows interesting properties in terms of sensitivity and performances, in different refractive index ranges. The development of highly sensitive platforms for high refractive index detection (higher than 1.38) is interesting for chemical applications based on molecularly imprinted polymer as receptors, while the aqueous medium is the refractive index range of biosensors based on bio-receptors. In this work we have presented an Au/Pd metal bilayer optimized for 1.38-1.42 refractive index range.

  17. An in-situ real-time optical fiber sensor based on surface plasmon resonance for monitoring the growth of TiO2 thin films.

    Science.gov (United States)

    Tsao, Yu-Chia; Tsai, Woo-Hu; Shih, Wen-Ching; Wu, Mu-Shiang

    2013-07-23

    An optical fiber sensor based on surface plasmon resonance (SPR) is proposed for monitoring the thickness of deposited nano-thin films. A side-polished multimode SPR optical fiber sensor with an 850 nm-LD is used as the transducing element for real-time monitoring of the deposited TiO2 thin films. The SPR optical fiber sensor was installed in the TiO2 sputtering system in order to measure the thickness of the deposited sample during TiO2 deposition. The SPR response declined in real-time in relation to the growth of the thickness of the TiO2 thin film. Our results show the same trend of the SPR response in real-time and in spectra taken before and after deposition. The SPR transmitted intensity changes by approximately 18.76% corresponding to 50 nm of deposited TiO2 thin film. We have shown that optical fiber sensors utilizing SPR have the potential for real-time monitoring of the SPR technology of nanometer film thickness. The compact size of the SPR fiber sensor enables it to be positioned inside the deposition chamber, and it could thus measure the film thickness directly in real-time. This technology also has potential application for monitoring the deposition of other materials. Moreover, in-situ real-time SPR optical fiber sensor technology is in inexpensive, disposable technique that has anti-interference properties, and the potential to enable on-line monitoring and monitoring of organic coatings.

  18. Fabrication of Long Period Gratings by Periodically Removing the Coating of Cladding-Etched Single Mode Optical Fiber Towards Optical Fiber Sensor Development

    Directory of Open Access Journals (Sweden)

    Joaquin Ascorbe

    2018-06-01

    Full Text Available Here, we present a novel method to fabricate long period gratings using standard single mode optical fibers (SMF. These optical devices were fabricated in a three-step process, which consisted of etching the SMF, then coating it with a thin-film and, the final step, which involved removing sections of the coating periodically by laser ablation. Tin dioxide was chosen as the material for this study and it was sputtered using a pulsed DC sputtering system. Theoretical simulations were performed in order to select the appropriate parameters for the experiments. The responses of two different devices to different external refractive indices was studied, and the maximum sensitivity obtained was 6430 nm/RIU for external refractive indices ranging from 1.37 to 1.39.

  19. Fabrication of Long Period Gratings by Periodically Removing the Coating of Cladding-Etched Single Mode Optical Fiber Towards Optical Fiber Sensor Development.

    Science.gov (United States)

    Ascorbe, Joaquin; Corres, Jesus M; Del Villar, Ignacio; Matias, Ignacio R

    2018-06-07

    Here, we present a novel method to fabricate long period gratings using standard single mode optical fibers (SMF). These optical devices were fabricated in a three-step process, which consisted of etching the SMF, then coating it with a thin-film and, the final step, which involved removing sections of the coating periodically by laser ablation. Tin dioxide was chosen as the material for this study and it was sputtered using a pulsed DC sputtering system. Theoretical simulations were performed in order to select the appropriate parameters for the experiments. The responses of two different devices to different external refractive indices was studied, and the maximum sensitivity obtained was 6430 nm/RIU for external refractive indices ranging from 1.37 to 1.39.

  20. A microstructured Polymer Optical Fiber Biosensor

    DEFF Research Database (Denmark)

    Emiliyanov, Grigoriy Andreev; Jensen, Jesper Bo; Hoiby, Poul E.

    2006-01-01

    We demonstrate selective detection of fluorophore labeled antibodies from minute samples probed by a sensor layer of the complementary biomolecules immobilized inside the air holes of microstructured Polymer Optical Fibers.......We demonstrate selective detection of fluorophore labeled antibodies from minute samples probed by a sensor layer of the complementary biomolecules immobilized inside the air holes of microstructured Polymer Optical Fibers....

  1. Monitoring of pipeline deformations using optical fiber sensors based on Bragg lattices; Monitoracao de deformacoes em dutos utilizando sensores a fibra optica com base em redes de Bragg

    Energy Technology Data Exchange (ETDEWEB)

    Moszkowica, Viktor Nigri [Pontificia Univ. Catolica do Rio de Janeiro, RJ (Brazil)]. E-mail: vnigri@bol.com.br

    2002-06-01

    In the petroleum sector there is a growing need for the use of pipelines as well as for their monitoring. A way to avoid leaks that can cause great damage to the environment is by the monitoring of deformations. In case failures can not be avoided through operational procedures, the monitoring of deformations can identify the initial moment and location of the leak, allowing for quick action on the part of the cleaning and depollution teams. Also important is the monitoring of slopes and soil movements. The same thing applies to production and transfer submarine pipelines subject to complex dynamic loadings that combine internal and external pressure, torsion, axial stress and, the most common of all, flexion loading. For this type of application, optical fiber sensors present a number of interesting features. Multiplexing, remote operation and long distance distribution of sensors are characteristics that attract their use in deformation monitoring systems. Presented herein are the research results of works that had the objective of developing deformation monitoring techniques in pipelines using optical fiber sensors based on Bragg grating. The technical feasibility of this technology is demonstrated through laboratorial tests. Also discussed herein are methods for field implementation of sensors, optical signal multiplexing techniques and potential advantages of applying this technology. (author)

  2. A hybrid optic-fiber sensor network with the function of self-diagnosis and self-healing

    Science.gov (United States)

    Xu, Shibo; Liu, Tiegen; Ge, Chunfeng; Chen, Cheng; Zhang, Hongxia

    2014-11-01

    We develop a hybrid wavelength division multiplexing optical fiber network with distributed fiber-optic sensors and quasi-distributed FBG sensor arrays which detect vibrations, temperatures and strains at the same time. The network has the ability to locate the failure sites automatically designated as self-diagnosis and make protective switching to reestablish sensing service designated as self-healing by cooperative work of software and hardware. The processes above are accomplished by master-slave processors with the help of optical and wireless telemetry signals. All the sensing and optical telemetry signals transmit in the same fiber either working fiber or backup fiber. We take wavelength 1450nm as downstream signal and wavelength 1350nm as upstream signal to control the network in normal circumstances, both signals are sent by a light emitting node of the corresponding processor. There is also a continuous laser wavelength 1310nm sent by each node and received by next node on both working and backup fibers to monitor their healthy states, but it does not carry any message like telemetry signals do. When fibers of two sensor units are completely damaged, the master processor will lose the communication with the node between the damaged ones.However we install RF module in each node to solve the possible problem. Finally, the whole network state is transmitted to host computer by master processor. Operator could know and control the network by human-machine interface if needed.

  3. Application of Negative Curvature Hollow-Core Fiber in an Optical Fiber Sensor Setup for Multiphoton Spectroscopy.

    Science.gov (United States)

    Popenda, Maciej Andrzej; Stawska, Hanna Izabela; Mazur, Leszek Mateusz; Jakubowski, Konrad; Kosolapov, Alexey; Kolyadin, Anton; Bereś-Pawlik, Elżbieta

    2017-10-06

    In this paper, an application of negative curvature hollow core fiber (NCHCF) in an all-fiber, multiphoton fluorescence sensor setup is presented. The dispersion parameter (D) of this fiber does not exceed the value of 5 ps/nm × km across the optical spectrum of (680-750) nm, making it well suited for the purpose of multiphoton excitation of biological fluorophores. Employing 1.5 m of this fiber in a simple, all-fiber sensor setup allows us to perform multiphoton experiments without any dispersion compensation methods. Multiphoton excitation of nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD) with this fiber shows a 6- and 9-fold increase, respectively, in the total fluorescence signal collected when compared with the commercial solution in the form of a hollow-core photonic band gap fiber (HCPBF). To the author's best knowledge, this is the first time an NCHCF was used in an optical-fiber sensor setup for multiphoton fluorescence experiments.

  4. Fabrication and characterization of polycarbonate microstructured polymer optical fibers for high-temperature-resistant fiber Bragg grating strain sensors

    DEFF Research Database (Denmark)

    Fasano, Andrea; Woyessa, Getinet; Stajanca, Pavol

    2016-01-01

    Here we present the fabrication of a solid-core microstructured polymer optical fiber (mPOF) made of polycarbonate (PC), and report the first experimental demonstration of a fiber Bragg grating (FBG) written in a PC optical fiber. The PC used in this work has a glass transition temperature of 145°C...

  5. Optical Fiber Protection

    Science.gov (United States)

    1999-01-01

    F&S Inc. developed and commercialized fiber optic and microelectromechanical systems- (MEMS) based instrumentation for harsh environments encountered in the aerospace industry. The NASA SBIR programs have provided F&S the funds and the technology to develop ruggedized coatings and coating techniques that are applied during the optical fiber draw process. The F&S optical fiber fabrication facility and developed coating methods enable F&S to manufacture specialty optical fiber with custom designed refractive index profiles and protective or active coatings. F&S has demonstrated sputtered coatings using metals and ceramics and combinations of each, and has also developed techniques to apply thin coatings of specialized polyimides formulated at NASA Langley Research Center. With these capabilities, F&S has produced cost-effective, reliable instrumentation and sensors capable of withstanding temperatures up to 800? C and continues building commercial sales with corporate partners and private funding. More recently, F&S has adapted the same sensing platforms to provide the rapid detection and identification of chemical and biological agents

  6. Optical fiber pH sensors for high temperature water. Final report

    International Nuclear Information System (INIS)

    McCrae, D.; Saaski, E.

    1994-11-01

    The goal of this program was the development of an optical pH measurement system capable of operating in a high-temperature aqueous environment. This project built upon a dual-wavelength fiber optic sensing system previously developed by Research International which utilizes light-emitting diodes as light sources and provides remote absorption spectroscopy via a single bidirectional optical fiber. Suitable materials for constructing an optical pH sensing element were identified during the program. These included a sapphire/Ti/Pt/Au thin-film reflector, quartz and sapphire waveguides, a poly(benzimidazole) matrix, and an azo chromophore indicator. By a suitable combination of these design elements, it appears possible to optically measure pH in aqueous systems up to a temperature of about 150 degrees C. A pH sensing system capable of operating in high-purity, low-conductivity water was built using quasi-evanescent wave sensing techniques. The sensing element incorporated a novel, mixed cellulose/cellulose acetate waveguide to which an azo indicator was bound. Testing revealed that the system could reproducibly respond to pH changes arising from 1 ppm differences in the morpholine content of low-conductivity water without influencing the measurement. The sensing system was stable for 150 hrs at room temperature, and no loss or degradation of the pH-responsive optical indicator was seen in 160 hrs at 50 degrees C. However, the prototype polymer waveguide lost transparency at 1.7% per day during this same 50 degrees C test. Additional effort is warranted in the areas of water-compatible waveguides and evanescent-wave detection methods

  7. Evaluation of Fiber Bragg Grating and Distributed Optical Fiber Temperature Sensors

    Energy Technology Data Exchange (ETDEWEB)

    McCary, Kelly Marie [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-04-01

    Fiber optic temperature sensors were evaluated in the High Temperature Test Lab (HTTL) to determine the accuracy of the measurements at various temperatures. A distributed temperature sensor was evaluated up to 550C and a fiber Bragg grating sensor was evaluated up to 750C. HTTL measurements indicate that there is a drift in fiber Bragg sensor over time of approximately -10C with higher accuracy at temperatures above 300C. The distributed sensor produced some bad data points at and above 500C but produced measurements with less than 2% error at increasing temperatures up to 400C

  8. Evaluation of Fiber Bragg Grating and Distributed Optical Fiber Temperature Sensors

    International Nuclear Information System (INIS)

    McCary, Kelly Marie

    2017-01-01

    Fiber optic temperature sensors were evaluated in the High Temperature Test Lab (HTTL) to determine the accuracy of the measurements at various temperatures. A distributed temperature sensor was evaluated up to 550C and a fiber Bragg grating sensor was evaluated up to 750C. HTTL measurements indicate that there is a drift in fiber Bragg sensor over time of approximately -10C with higher accuracy at temperatures above 300C. The distributed sensor produced some bad data points at and above 500C but produced measurements with less than 2% error at increasing temperatures up to 400C

  9. Differential in vivo urodynamic measurement in a single thin catheter based on two optical fiber pressure sensors.

    Science.gov (United States)

    Poeggel, Sven; Duraibabu, Dineshbabu; Tosi, Daniele; Leen, Gabriel; Lewis, Elfed; McGrath, Deirdre; Fusco, Ferdinando; Sannino, Simone; Lupoli, Laura; Ippolito, Juliet; Mirone, Vincenzo

    2015-03-01

    Urodynamic analysis is the predominant method for evaluating dysfunctions in the lower urinary tract. The exam measures the pressure during the filling and voiding process of the bladder and is mainly interested in the contraction of the bladder muscles. The data arising out of these pressure measurements enables the urologist to arrive at a precise diagnosis and prescribe an adequate treatment. A technique based on two optical fiber pressure and temperature sensors with a resolution of better than 0.1 cm H₂O (∼10 Pa), a stability better than 1 cm H₂O/hour, and a diameter of 0.2 mm in a miniature catheter with a diameter of only 5 Fr (1.67 mm), was used. This technique was tested in vivo on four patients with a real-time urodynamic measurement system. The optical system presented showed a very good correlation to two commercially available medical reference sensors. Furthermore, the optical urodynamic system demonstrated a higher dynamic and better sensitivity to detect small obstructions than both pre-existing medical systems currently in use in the urodynamic field.

  10. Surface-enhanced Raman scattering of amorphous silica gel adsorbed on gold substrates for optical fiber sensors

    Science.gov (United States)

    Degioanni, S.; Jurdyc, A. M.; Cheap, A.; Champagnon, B.; Bessueille, F.; Coulm, J.; Bois, L.; Vouagner, D.

    2015-10-01

    Two kinds of gold substrates are used to produce surface-enhanced Raman scattering (SERS) of amorphous silica obtained via the sol-gel route using tetraethoxysilane Si(OC2H5)4 (TEOS) solution. The first substrate consists of a gold nanometric film elaborated on a glass slide by sputter deposition, controlling the desired gold thickness and sputtering current intensity. The second substrate consists of an array of micrometer-sized gold inverted pyramidal pits able to confine surface plasmon (SP) enhancing electric field, which results in a distribution of electromagnetic energy inside the cavities. These substrates are optically characterized to observe SPR with, respectively, extinction and reflectance spectrometries. Once coated with thin layers of amorphous silica (SiO2) gel, these samples show Raman amplification of amorphous SiO2 bands. This enhancement can occur in SERS sensors using amorphous SiO2 gel as shells, spacers, protective coatings, or waveguides, and represents particularly a potential interest in the field of Raman distributed sensors, which use the amorphous SiO2 core of optical fibers as a transducer to make temperature measurements.

  11. Development and evaluation of optical fiber NH3 sensors for application in air quality monitoring

    Science.gov (United States)

    Huang, Yu; Wieck, Lucas; Tao, Shiquan

    2013-02-01

    Ammonia is a major air pollutant emitted from agricultural practices. Sources of ammonia include manure from animal feeding operations and fertilizer from cropping systems. Sensor technologies with capability of continuous real time monitoring of ammonia concentration in air are needed to qualify ammonia emissions from agricultural activities and further evaluate human and animal health effects, study ammonia environmental chemistry, and provide baseline data for air quality standard. We have developed fiber optic ammonia sensors using different sensing reagents and different polymers for immobilizing sensing reagents. The reversible fiber optic sensors have detection limits down to low ppbv levels. The response time of these sensors ranges from seconds to tens minutes depending on transducer design. In this paper, we report our results in the development and evaluation of fiber optic sensor technologies for air quality monitoring. The effect of change of temperature, humidity and carbon dioxide concentration on fiber optic ammonia sensors has been investigated. Carbon dioxide in air was found not interfere the fiber optic sensors for monitoring NH3. However, the change of humidity can cause interferences to some fiber optic NH3 sensors depending on the sensor's transducer design. The sensitivity of fiber optic NH3 sensors was found depends on temperature. Methods and techniques for eliminating these interferences have been proposed.

  12. Poly aniline Nano fiber as Modified Cladding for Optical Fiber Sensor to Detect Acetone Vapor

    International Nuclear Information System (INIS)

    Akhiruddin maddu; Ahmad aminuddin; Setyanto Tri Wahyudi; Hamdani Zain

    2008-01-01

    In this research, we used poly aniline nano fiber as modified cladding material for a fiber optic sensor system to detect the acetone vapor. The sensor was designed based on variation of evanescent field absorption on the core-modified cladding interface when exposed with varied acetone vapor. Poly aniline nano fiber synthesized by interfacial polymerization was coated onto the un-cladded core and acts as sensing element. Response of the fiber optic sensor was investigated by measuring the transmission light intensity via fiber optic sensor system while exposed with acetone vapor. Based on the sensor response curve, it is obtained a very fast response time of 30 s and recovery time of 10 s. The fiber optic sensor also exhibits a good reversibility and repeatability. Sensitivity of the sensor to variation of acetone vapor pressure was obtained 1.25 %/mmHg, that means the transmission intensity of the sensor changes 1.25 % for acetone vapor change of 1 mmHg. (author)

  13. High sensitivity optical fiber liquid level sensor based on a compact MMF-HCF-FBG structure

    Science.gov (United States)

    Zhang, Yunshan; Zhang, Weigang; Chen, Lei; Zhang, Yanxin; Wang, Song; Yan, Tieyi

    2018-05-01

    An ultra-high sensitivity fiber liquid level sensor based on wavelength demodulation is proposed and demonstrated. The sensor is composed of a segment of multimode fiber and a large aperture hollow-core fiber assisted by a fiber Bragg grating (FBG). Interference occurs due to core mismatching and different modes with different effective refractive indices. The experimental results show that the liquid level sensitivity of the sensor is 1.145 nm mm‑1, and the linearity is up to 0.996. The dynamic temperature compensation of the sensor can be achieved by cascading an FBG. Considering the high sensitivity and compact structure of the sensor, it can be used for real-time intelligent monitoring of tiny changes in liquid level.

  14. Urinary p-cresol diagnosis using nanocomposite of ZnO/MoS2 and molecular imprinted polymer on optical fiber based lossy mode resonance sensor.

    Science.gov (United States)

    Usha, Sruthi P; Gupta, Banshi D

    2018-03-15

    A lossy mode resonance (LMR) based sensor for urinary p-cresol testing on optical fiber substrate is developed. The sensor probe fabrication includes dip coating of nanocomposite layer of zinc oxide and molybdenum sulphide (ZnO/MoS 2 ) over unclad core of optical fiber as the transducer layer followed by the layer of molecular imprinted polymer (MIP) as the recognition medium. The addition of molybdenum sulphide in the transducer layer increases the absorption of light in the medium which enhances the LMR properties of zinc oxide thereby increasing the conductivity and hence the sensitivity of the sensor. The sensor probe is characterized for p-cresol concentration range from 0µM (reference sample) to 1000µM in artificially prepared urine. Optimizations of various probe fabrication parameters are carried to bring out the sensor's optimal performance with a sensitivity of 11.86nm/µM and 28nM as the limit of detection (LOD). A two-order improvement in LOD is obtained as compared to the recently reported p-cresol sensor. The proposed sensor possesses a response time of 15s which is 8 times better than that reported in the literature utilizing electrochemical method. Its response time is also better than the p-cresol sensor currently available in the market for the medical field. Thus, with a fast response, significant stability and repeatability, the proposed sensor holds practical implementation possibilities in the medical field. Further, the realization of sensor probe over optical fiber substrate adds remote sensing and online monitoring feasibilities. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Optical Fiber Chemical Sensor with Sol-Gel Derived Refractive Material as Transducer for High Temperature Gas Sensing in Clean Coal Technology

    Energy Technology Data Exchange (ETDEWEB)

    Shiquan Tao

    2006-12-31

    The chemistry of sol-gel derived silica and refractive metal oxide has been systematically studied. Sol-gel processes have been developed for preparing porous silica and semiconductor metal oxide materials. Micelle/reversed micelle techniques have been developed for preparing nanometer sized semiconductor metal oxides and noble metal particles. Techniques for doping metal ions, metal oxides and nanosized metal particles into porous sol-gel material have also been developed. Optical properties of sol-gel derived materials in ambient and high temperature gases have been studied by using fiber optic spectroscopic techniques, such as fiber optic ultraviolet/visible absorption spectrometry, fiber optic near infrared absorption spectrometry and fiber optic fluorescence spectrometry. Fiber optic spectrometric techniques have been developed for investigating the optical properties of these sol-gel derived materials prepared as porous optical fibers or as coatings on the surface of silica optical fibers. Optical and electron microscopic techniques have been used to observe the microstructure, such as pore size, pore shape, sensing agent distribution, of sol-gel derived material, as well as the size and morphology of nanometer metal particle doped in sol-gel derived porous silica, the nature of coating of sol-gel derived materials on silica optical fiber surface. In addition, the chemical reactions of metal ion, nanostructured semiconductor metal oxides and nanometer sized metal particles with gas components at room temperature and high temperatures have also been investigated with fiber optic spectrometric methods. Three classes of fiber optic sensors have been developed based on the thorough investigation of sol-gel chemistry and sol-gel derived materials. The first group of fiber optic sensors uses porous silica optical fibers doped with metal ions or metal oxide as transducers for sensing trace NH{sub 3} and H{sub 2}S in high temperature gas samples. The second group of

  16. Humidity Sensor Based on Bragg Gratings Developed on the End Facet of an Optical Fiber by Sputtering of One Single Material

    Directory of Open Access Journals (Sweden)

    Joaquin Ascorbe

    2017-04-01

    Full Text Available The refractive index of sputtered indium oxide nanocoatings has been altered just by changing the sputtering parameters, such as pressure. These induced changes have been exploited for the generation of a grating on the end facet of an optical fiber towards the development of wavelength-modulated optical fiber humidity sensors. A theoretical analysis has also been performed in order to study the different parameters involved in the fabrication of this optical structure and how they would affect the sensitivity of these devices. Experimental and theoretical results are in good agreement. A sensitivity of 150 pm/%RH was obtained for relative humidity changes from 20% to 60%. This kind of humidity sensors shows a maximum hysteresis of 1.3% relative humidity.

  17. Health monitoring of unmanned aerial vehicle based on optical fiber sensor array

    Science.gov (United States)

    Luo, Yuxiang; Shen, Jingshi; Shao, Fei; Guo, Chunhui; Yang, Ning; Zhang, Jiande

    2017-10-01

    The unmanned aerial vehicle (UAV) in flight needs to face the complicated environment, especially to withstand harsh weather conditions, such as the temperature and pressure. Compared with conventional sensors, fiber Bragg grating (FBG) sensor has the advantages of small size, light weight, high reliability, high precision, anti-electromagnetic interference, long lift-span, moistureproof and good resistance to causticity. It's easy to be embedded in composite structural components of UAVs. In the paper, over 1000 FBG sensors distribute regularly on a wide range of UAVs body, combining wavelength division multiplexing (WDM), time division multiplexing (TDM) and multichannel parallel architecture. WDM has the advantage of high spatial resolution. TDM has the advantage of large capacity and wide range. It is worthful to constitute a sensor network by different technologies. For the signal demodulation of FBG sensor array, WDM works by means of wavelength scanning light sources and F-P etalon. TDM adopts the technology of optical time-domain reflectometry. In order to demodulate efficiently, the most proper sensor multiplex number with some reflectivity is given by the curves fitting. Due to the regular array arrangement of FBG sensors on the UAVs, we can acquire the health state of UAVs in the form of 3D visualization. It is helpful to master the information of health status rapidly and give a real-time health evaluation.

  18. Sensor system for multi-point monitoring using bending loss of single mode optical fiber

    International Nuclear Information System (INIS)

    Kim, Heon Young; Kim, Dae Hyun

    2015-01-01

    Applications of smart sensors have been extended to safety systems in the aerospace, transportation and civil engineering fields. In particular, structural health monitoring techniques using smart sensors have gradually become necessary and have been developed to prevent dangers to human life and damage to assets. Generally, smart sensors are based on electro-magnets and have several weaknesses, including electro-magnetic interference and distortion. Therefore, fiber optic sensors are an outstanding alternative to overcome the weaknesses of electro-magnetic sensors. However, they require expensive devices and complex systems. This paper proposes a new, affordable and simple sensor system that uses a single fiber to monitor pressures at multiple-points. Moreover, a prototype of the sensor system was manufactured and tested for a feasibility study. Based on the results of this experimental test, a relationship was carefully observed between the bend loss conditions and light-intensity. As a result, it was shown that impacts at multiple-points could be monitored.

  19. Hopfield neural network and optical fiber sensor as intelligent heart rate monitor

    Science.gov (United States)

    Mutter, Kussay Nugamesh

    2018-01-01

    This paper presents a design and fabrication of an intelligent fiber-optic sensor used for examining and monitoring heart rate activity. It is found in the literature that the use of fiber sensors as heart rate sensor is widely studied. However, the use of smart sensors based on Hopfield neural networks is very low. In this work, the sensor is a three fibers without cladding of about 1 cm, fed by laser light of 1550 nm of wavelength. The sensing portions are mounted with a micro sensitive diaphragm to transfer the pulse pressure on the left radial wrist. The influenced light intensity will be detected by a three photodetectors as inputs into the Hopfield neural network algorithm. The latter is a singlelayer auto-associative memory structure with a same input and output layers. The prior training weights are stored in the net memory for the standard recorded normal heart rate signals. The sensors' heads work on the reflection intensity basis. The novelty here is that the sensor uses a pulse pressure and Hopfield neural network in an integrity approach. The results showed a significant output measurements of heart rate and counting with a plausible error rate.

  20. Distributed dual-parameter optical fiber sensor based on cascaded microfiber Fabry-Pérot interferometers

    Science.gov (United States)

    Xiang, Yang; Luo, Yiyang; Zhang, Wei; Liu, Deming; Sun, Qizhen

    2017-04-01

    We propose and demonstrate a distributed fiber sensor based on cascaded microfiber Fabry-Perot interferometers (MFPI) for simultaneous refractive index (SRI) and temperature measurement. By employing MFPI which is fabricated by taper-drawing the center of a uniform fiber Bragg grating (FBG) on standard fiber into a section of microfiber, dual parameters including SRI and temperature can be detected through demodulating the reflection spectrum of the MFPI. Further, wavelength-division-multiplexing (WDM) is applied to realize distributed dual-parameter fiber sensor by using cascaded MFPIs with different Bragg wavelengths. A prototype sensor system with 5 cascaded MFPIs is constructed to experimentally demonstrate the sensing performance.

  1. Tapered Optical Fiber Sensor for Detection of pH in Microscopic Volumes

    Czech Academy of Sciences Publication Activity Database

    Podrazký, Ondřej; Matějec, Vlastimil; Mrázek, Jan; Martan, Tomáš; Aubrecht, Jan; Kašík, Ivan

    2014-01-01

    Roč. 27, May (2014), s. 312-328 ISSN 2306-8515 Institutional support: RVO:67985882 Keywords : Optical sensor s * Fluorescence * Microfiber tip Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  2. Effective refractive index modulation based optical fiber humidity sensor employing etched fiber Bragg grating

    Science.gov (United States)

    Mundendhar, Pathi; Khijwania, Sunil K.

    2015-09-01

    Relative humidity (RH) sensor employing etched fiber Bragg grating (FBG) is reported where RH variations are captured using effective-index-modulation, rather than traditional strain-modulation. Additionly, linear sensor response over wide dynamic range with optimum characteristics is focused. Comprehensive experimental investigation is carried out for the sensor that comprises uniformly etched cladding in the FBG region. Obtained results are observed to be in agreement with the theoretical analysis. Sensor response is observed to be linear over dynamic range 3-94%RH with ~ 0.082 pm/%RH sensitivity, ~0.6%RH resolution, ~ +/-2.5%RH accuracy, ~ +/-0.2 pm average discrepancy and ~ 0.2s response time during humidification/desiccation.

  3. Intrusion recognition for optic fiber vibration sensor based on the selective attention mechanism

    Science.gov (United States)

    Xu, Haiyan; Xie, Yingjuan; Li, Min; Zhang, Zhuo; Zhang, Xuewu

    2017-11-01

    Distributed fiber-optic vibration sensors receive extensive investigation and play a significant role in the sensor panorama. A fiber optic perimeter detection system based on all-fiber interferometric sensor is proposed, through the back-end analysis, processing and intelligent identification, which can distinguish effects of different intrusion activities. In this paper, an intrusion recognition based on the auditory selective attention mechanism is proposed. Firstly, considering the time-frequency of vibration, the spectrogram is calculated. Secondly, imitating the selective attention mechanism, the color, direction and brightness map of the spectrogram is computed. Based on these maps, the feature matrix is formed after normalization. The system could recognize the intrusion activities occurred along the perimeter sensors. Experiment results show that the proposed method for the perimeter is able to differentiate intrusion signals from ambient noises. What's more, the recognition rate of the system is improved while deduced the false alarm rate, the approach is proved by large practical experiment and project.

  4. Quasidistributed temperature sensor based on dense wavelength-division multiplexing optical fiber delay

    Science.gov (United States)

    Su, Jun; Yang, Ning; Fan, Zhiqiang; Qiu, Qi

    2017-10-01

    We report on a fiber-optic delay-based quasidistributed temperature sensor with high precision. The device works by detecting the delay induced by the temperature instead of the spectrum. To analyze the working principle of this sensor, the thermal dependence of the fiber-optic delay was theoretically investigated and the delay-temperature coefficient was measured to be 42.2 ps/km°C. In this sensor, quasidistributed measurement of temperature could be easily realized by dense wavelength-division multiplexing and wavelength addressing. We built and tested a prototype quasidistributed temperature sensor with eight testing points equally distributed along a 32.61-km-long fiber. The experimental results demonstrate an average error of economic temperature measurements.

  5. Optical fiber sensors based on novel polyimide for humidity monitoring of building materials

    Science.gov (United States)

    Chai, Jing; Liu, Qi; Liu, Jinxuan; Zhang, Dingding

    2018-03-01

    This paper presents novel preparation methods of polyimide and coupling agent, coated on the fiber Bragg grating (FBG) sensor for monitoring relative humidity (RH). The sensing mechanism that the volume change of the moisture-sensitive polyimide induces the shift of the Bragg wavelength of FBG is used in the RH sensor. The performance of the polymer-coated RH sensor was evaluated under laboratory conditions of temperature over a range of values (20.0-80.0 °C) and humidity over a range of RH values (25.0-95.0%). The time response and RH sensitivity of the sensor based on novel polyimide and coupling agent was improved, compared to the previous. A new packaged RH sensor was designed, which was used in detecting the moisture diffusion and evolutions inside of sample made of building materials which exposed to a controlled environment in the lab after casting. Relative humidity inside of sample with time was 100% in the first phase of vapor-saturated, slowly reduced in the latter phase. The results indicate the RH sensor developed provides a feasible method to detect the influence of environment on moisture inside the material in the drying process.

  6. A Preliminary Test for Skin Gas Assessment Using a Porphyrin Based Evanescent Wave Optical Fiber Sensor

    Directory of Open Access Journals (Sweden)

    Roman SELYANCHYN

    2011-02-01

    Full Text Available An evanescent-wave optical fibre sensor modified with tetrakis-(4-sulfophenyl porphine (TSPP and poly(allylamine hydrochloride (PAH bilayers using layer-by-layer (LbL electrostatic self-assembly was tested to measure the gas emitted from human skin. Optical intensity changes at different wavelengths in the transmission spectrum of the porphyrin-based film were induced by the human skin gas and measured as sensor response. Influence of relative humidity, which can be a major interference to sensor response, was thoroughly studied and shown to be significantly different when compared to the influence of skin emanations. Responses of the current optical sensor system could be considered as composite sensor array, where different optical wavelengths act as channels that have selective response to specific volatile compounds. Data obtained from the sensor system was analyzed using principal component analysis (PCA. This approach enabled to distinguish skin odors of different people and their altered physiological conditions after alcohol consumption.

  7. Optical fiber grating vibration sensor for vibration monitoring of hydraulic pump

    Science.gov (United States)

    Zhang, Zhengyi; Liu, Chuntong; Li, Hongcai; He, Zhenxin; Zhao, Xiaofeng

    2017-06-01

    In view of the existing electrical vibration monitoring traditional hydraulic pump vibration sensor, the high false alarm rate is susceptible to electromagnetic interference and is not easy to achieve long-term reliable monitoring, based on the design of a beam of the uniform strength structure of the fiber Bragg grating (FBG) vibration sensor. In this paper, based on the analysis of the vibration theory of the equal strength beam, the principle of FBG vibration tuning based on the equal intensity beam is derived. According to the practical application of the project, the structural dimensions of the equal strength beam are determined, and the optimization design of the vibrator is carried out. The finite element analysis of the sensor is carried out by ANSYS, and the first order resonant frequency is 94.739 Hz. The vibration test of the sensor is carried out by using the vibration frequency of 35 Hz and the vibration source of 50 Hz. The time domain and frequency domain analysis results of test data show that the sensor has good dynamic response characteristics, which can realize the accurate monitoring of the vibration frequency and meet the special requirements of vibration monitoring of hydraulic pump under specific environment.

  8. A wide range and highly sensitive optical fiber pH sensor using polyacrylamide hydrogel

    Science.gov (United States)

    Pathak, Akhilesh Kumar; Singh, Vinod Kumar

    2017-12-01

    In the present study we report the fabrication and characterization of no-core fiber sensor (NCFS) using smart hydrogel coating for pH measurement. The no-core fiber (NCF) is stubbed between two single-mode fibers with SMA connector before immobilizing of smart hydrogel. The wavelength interrogation technique is used to calculate the sensitivity of the proposed sensor. The result shows a high sensitivity of 1.94 nm/pH for a wide range of pH values varied from 3 to 10 with a good linear response. In addition to high sensitivity, the fabricated sensor provides a fast response time with a good stability, repeatability and reproducibility.

  9. Optical fiber sensors for process refractometry and temperature measuring based on curved fibers

    International Nuclear Information System (INIS)

    Willsch, R.; Schwotzer, G.; Haubenreisser, W.; Jahn, J.U.

    1986-01-01

    Based on U-shape curved multimode fibers with defined bending radii intensity-modulated optical sensors for the determination of refractive index changes in liquids and related measurands (solution concentration, mixing ratio and others) in process-refractometry and for temperature measuring under special environmental conditions have been developed. The optoelectronic transmitting and receiving units are performed in modular technique and can be used in multi-purpose applications. The principles, performance and characteristical properties of these sensors are described and their possibilities of application in process measuring and automation are discussed by some selected examples. (orig.) [de

  10. Optical fiber sensors for process refractometry and temperature measuring based on curved fibers

    Energy Technology Data Exchange (ETDEWEB)

    Willsch, R; Schwotzer, G; Haubenreisser, W; Jahn, J U

    1986-01-01

    Based on U-shape curved multimode fibers with defined bending radii intensity-modulated optical sensors for the determination of refractive index changes in liquids and related measurands (solution concentration, mixing ratio and others) in process-refractometry and for temperature measuring under special environmental conditions have been developed. The optoelectronic transmitting and receiving units are performed in modular technique and can be used in multi-purpose applications. The principles, performance and characteristical properties of these sensors are described and their possibilities of application in process measuring and automation are discussed by some selected examples.

  11. Sensitivity of a long-period optical fiber grating bend sensor

    DEFF Research Database (Denmark)

    Rathje, Jacob; Svalgaard, Mikael; Hübner, Jörg

    1998-01-01

    We have investigated the sensitivity of long-period fiber gratings used in curvature measuring fibre optic sensors and found a bend coefficient of 0.77 dB cm/mrad. In the current setup this corresponds to the ability of detecting curvatures with a radius up to approximately 200 m...

  12. Crack growth monitoring in composite materials using embedded optical Fiber Bragg Grating sensor

    DEFF Research Database (Denmark)

    Pereira, Gilmar Ferreira; Mikkelsen, Lars Pilgaard; McGugan, Malcolm

    2015-01-01

    In this paper a novel method to assess a crack growing/damage event in fiber reinforced plastic, or adhesive using Fiber Bragg Grating (FBG) sensors embedded in a host material is shown. Different features of the crack mechanism that induce a change in the FBG response were identified. Double...

  13. Clinical measuring system for the form and position errors of circular workpieces using optical fiber sensors

    Science.gov (United States)

    Tan, Jiubin; Qiang, Xifu; Ding, Xuemei

    1991-08-01

    Optical sensors have two notable advantages in modern precision measurement. One is that they can be used in nondestructive measurement because the sensors need not touch the surfaces of workpieces in measuring. The other one is that they can strongly resist electromagnetic interferences, vibrations, and noises, so they are suitable to be used in machining sites. But the drift of light intensity and the changing of the reflection coefficient at different measuring positions of a workpiece may have great influence on measured results. To solve the problem, a spectroscopic differential characteristic compensating method is put forward. The method can be used effectively not only in compensating the measuring errors resulted from the drift of light intensity but also in eliminating the influence to measured results caused by the changing of the reflection coefficient. Also, the article analyzes the possibility of and the means of separating data errors of a clinical measuring system for form and position errors of circular workpieces.

  14. Surface refractive index of the eye lens determined with an optic fiber sensor

    International Nuclear Information System (INIS)

    Pierscionek, B.K.

    1993-01-01

    The use of a fiber optic sensor for measurement of refractive index on the surface of eye lenses is described. The technique makes use of the fact that the amount of light reflected at the interface of two media (Fresnel reflectance) depends on the refractive-index difference between them. The sample is probed with a single-mode fiber, and the refractive index is calculated from the proportion of light reflected at the probe--sample interface

  15. Optical fiber temperature sensor based on dumbbell-shaped Mach-Zehnder interferometer

    Science.gov (United States)

    Tan, Jianchang; Feng, Guoying; Liang, Jingchuan; Zhang, Shulin

    2018-01-01

    A dumbbell-shaped and core-disconnected microstructure all-fiber temperature sensor based on the Mach-Zehnder interferometer (MZI) is designed and implemented. To the best of our knowledge, the MZI with this configuration was produced and applied to sense temperature for the first time. It demonstrated that this all-fiber interferometer incorporates intermodal interference between the LP01 mode and a high-order cladding mode of LP07. Theoretical and experimental results indicate that the linearity of the spectral shift due to the temperature change is ˜0.999 and the sensitivity at 25°C to 400°C is ˜26.03 pm/°C and at -25°C to 20°C is ˜23.87 pm/°C. The reproducibility error of this all-fiber temperature sensor at 25°C to 400°C is innovative micro-nano all-fiber sensors.

  16. Near Infrared Characterization of Hetero-Core Optical Fiber SPR Sensors Coated with Ta2O5 Film and Their Applications

    Directory of Open Access Journals (Sweden)

    Kazuhiro Watanabe

    2012-02-01

    Full Text Available This paper describes the characteristics of optical fiber sensors with surface plasmon resonance (SPR at 1,310 nm in which the scattering loss of silica optical fiber is low. SPR operation in the infrared wavelength range is achieved by coating a thin tantalum pentaoxide (Ta2O5 film. The novelty of this paper lies in the verification of how the hetero-core scheme could be operated as a commercial base candidate in the sense of easy fabrication, sufficient mechanical strength, and significant sensitivity as a liquid detector under the basis of a low loss transmission network in the near infrared wavelength region. The effect of Ta2O5 layer thickness has been experimentally revealed in the wavelength region extending to 1,800 nm by using the hetero-core structured optical fiber. SPR characterizations have been made in the wavelength region 1,000–1,300 nm, showing the feasible operation at the near infrared wavelength and the possible practical applications. In addition, the technique developed in this work has been interestingly applied to a multi-point water-detection and a water-level gauge in which tandem-connected SPR sensors system using hetero-core structured fibers were incorporated. The detailed performance characteristics are also shown on these applications.

  17. Note: Durability analysis of optical fiber hydrogen sensor based on Pd-Y alloy film.

    Science.gov (United States)

    Huang, Peng-cheng; Chen, You-ping; Zhang, Gang; Song, Han; Liu, Yi

    2016-02-01

    The Pd-Y alloy sensing film has an excellent property for hydrogen detection, but just for one month, the sensing film's property decreases seriously. To study the failure of the sensing film, the XPS spectra analysis was used to explore the chemical content of the Pd-Y alloy film, and analysis results demonstrate that the yttrium was oxidized. The paper presented that such an oxidized process was the potential reason of the failure of the sensing film. By understanding the reason of the failure of the sensing film better, we could improve the manufacturing process to enhance the property of hydrogen sensor.

  18. Optical fiber tip interferometer gas pressure sensor based on anti-resonant reflecting guidance mechanism

    Science.gov (United States)

    Yang, Y. B.; Wang, D. N.; Xu, Ben; Wang, Z. K.

    2018-05-01

    We propose and demonstrate a gas pressure sensor based on an anti-resonant reflecting guidance (ARRG) mechanism in quartz capillary tube with an open cavity. The device is simple in fabrication by only fusion splicing a segment of capillary tube with single mode fiber. It has compact size, robust structure, convenient mode of operation, and high sensitivity of 4.278 nm/MPa. Moreover, as two Faby-Perot cavities exist in the device, which create the interference spectrum with several distinct resonance dips, a simultaneous gas pressure and temperature detection can be readily achieved by tracing two dip wavelengths. The error in the measurement due to the choice of different resonant dips can be effectively reduced by using the Fourier band pass filtering method.

  19. Dynamic 3D strain measurements with embedded micro-structured optical fiber Bragg grating sensors during impact on a CFRP coupon

    Science.gov (United States)

    Goossens, Sidney; Geernaert, Thomas; De Pauw, Ben; Lamberti, Alfredo; Vanlanduit, Steve; Luyckx, Geert; Chiesura, Gabriele; Thienpont, Hugo; Berghmans, Francis

    2017-04-01

    Composite materials are increasingly used in aerospace applications, owing to their high strength-to-mass ratio. Such materials are nevertheless vulnerable to impact damage. It is therefore important to investigate the effects of impacts on composites. Here we embed specialty microstructured optical fiber Bragg grating based sensors inside a carbon fiber reinforced polymer, providing access to the 3D strain evolution within the composite during impact. We measured a maximum strain of -655 μɛ along the direction of impact, and substantially lower values in the two in-plane directions. Such in-situ characterization can trigger insight in the development of impact damage in composites.

  20. Application Specific Optical Fibers

    OpenAIRE

    Pal, Bishnu P.

    2010-01-01

    In this chapter we have attempted to provide a unified summary description of the most important propagation characteristics of an optical fiber followed by discussion on several variety of special fibers for realizing fiber amplifiers, dispersion compensating fibers, microstructured optical fibers, and so on. Even though huge progress has been made on development of optical fibers for telecom application, a need for developing special fibers, not necessarily for telecom alone, has arisen. Th...

  1. Magneto-Optic Field Coupling in Optical Fiber Bragg Gratings

    Science.gov (United States)

    Carman, Gregory P. (Inventor); Mohanchandra, Panduranga K. (Inventor); Emmons, Michael C. (Inventor); Richards, William Lance (Inventor)

    2016-01-01

    The invention is a magneto-optic coupled magnetic sensor that comprises a standard optical fiber Bragg grating system. The system includes an optical fiber with at least one Bragg grating therein. The optical fiber has at least an inner core and a cladding that surrounds the inner core. The optical fiber is part of an optical system that includes an interrogation device that provides a light wave through the optical fiber and a system to determine the change in the index of refraction of the optical fiber. The cladding of the optical fiber comprises at least a portion of which is made up of ferromagnetic particles so that the ferromagnetic particles are subject to the light wave provided by the interrogation system. When a magnetic field is present, the ferromagnetic particles change the optical properties of the sensor directly.

  2. Linear all-fiber temperature sensor based on macro-bent erbium doped fiber

    International Nuclear Information System (INIS)

    Hajireza, P; Cham, C L; Kumar, D; Abdul-Rashid, H A; Emami, S D; Harun, S W

    2010-01-01

    A new all fiber temperature sensor is proposed and demonstrated based on a pair of 1 meter erbium-doped fiber (EDF), which are respectively macro-bent and straight. The sensor has a linear normalized loss (dB) response to temperature at 6.5 mm bending radius and 1580 nm input wavelength. The main advantage of this sensor is high temperature resolution (less than 1°C) and sensitivity (0.03 dB/°C) due to combination of temperature dependence of EDF and bending loss. The proposed silica based sensor, has the potential for wide range and high temperature applications in harsh environments

  3. Demonstration and Methodology of Structural Monitoring of Stringer Runs out Composite Areas by Embedded Optical Fiber Sensors and Connectors Integrated during Production in a Composite Plant.

    Science.gov (United States)

    Miguel Giraldo, Carlos; Zúñiga Sagredo, Juan; Sánchez Gómez, José; Corredera, Pedro

    2017-07-21

    Embedding optical fibers sensors into composite structures for Structural Health Monitoring purposes is not just one of the most attractive solutions contributing to smart structures, but also the optimum integration approach that insures maximum protection and integrity of the fibers. Nevertheless this intended integration level still remains an industrial challenge since today there is no mature integration process in composite plants matching all necessary requirements. This article describes the process developed to integrate optical fiber sensors in the Production cycle of a test specimen. The sensors, Bragg gratings, were integrated into the laminate during automatic tape lay-up and also by a secondary bonding process, both in the Airbus Composite Plant. The test specimen, completely representative of the root joint of the lower wing cover of a real aircraft, is comprised of a structural skin panel with the associated stringer run out. The ingress-egress was achieved through the precise design and integration of miniaturized optical connectors compatible with the manufacturing conditions and operational test requirements. After production, the specimen was trimmed, assembled and bolted to metallic plates to represent the real triform and buttstrap, and eventually installed into the structural test rig. The interrogation of the sensors proves the effectiveness of the integration process; the analysis of the strain results demonstrate the good correlation between fiber sensors and electrical gauges in those locations where they are installed nearby, and the curvature and load transfer analysis in the bolted stringer run out area enable demonstration of the consistency of the fiber sensors measurements. In conclusion, this work presents strong evidence of the performance of embedded optical sensors for structural health monitoring purposes, where in addition and most importantly, the fibers were integrated in a real production environment and the ingress

  4. Single mode step-index polymer optical fiber for humidity insensitive high temperature fiber Bragg grating sensors

    DEFF Research Database (Denmark)

    Woyessa, Getinet; Fasano, Andrea; Stefani, Alessio

    2016-01-01

    We have fabricated the first single-mode step-index and humidity insensitive polymer optical fiber operating in the 850 nm wavelength ranges. The step-index preform is fabricated using injection molding, which is an efficient method for cost effective, flexible and fast preparation of the fiber...... preform. The fabricated single-mode step-index (SI) polymer optical fiber (POF) has a 4.8µm core made from TOPAS grade 5013S-04 with a glass transition temperature of 134°C and a 150 µm cladding made from ZEONEX grade 480R with a glass transition temperature of 138°C. The key advantages of the proposed...... SIPOF are low water absorption, high operating temperature and chemical inertness to acids and bases and many polar solvents as compared to the conventional poly-methyl-methacrylate (PMMA) and polystyrene based POFs. In addition, the fiber Bragg grating writing time is short compared to microstructured...

  5. Alcohol sensor based on u-bent hetero-structured fiber optic

    Science.gov (United States)

    Patrialova, Sefi N.; Hatta, Agus M.; Sekartedjo, Sekartedjo

    2016-11-01

    A sensor based on a fiber optic hetero-structure to determine the concentration of alcohol has been proposed. The structure of the sensing probe in this research is a singlemode-multimode-singlemode (SMS) which bent into Ushaped and soon called as SMS u-bent. The SMS structure was chosen to get a higher sensitivity. This research utilizes the principle of multimode interference and evanescent field by modifying the cladding with various alcohol concentration. Testing of the sensor's performance has been done by measuring the sensor's power output response to the length of the SMS fiber optic, bending diameter, and alcohol concentration. Based on the experiment result, the ubent SMS fiber optic with 50 mm bending diameter and 63 mm MMF lenght has the highest sensitivity, 3.87 dB/% and the minimum resolution, 0.26 x 10-3 %.

  6. Recent Development in Optical Fiber Biosensors

    Directory of Open Access Journals (Sweden)

    Catalina Bosch Ojeda

    2007-06-01

    Full Text Available Remarkable developments can be seen in the field of optical fibre biosensors in the last decade. More sensors for specific analytes have been reported, novel sensing chemistries or transduction principles have been introduced, and applications in various analytical fields have been realised. This review consists of papers mainly reported in the last decade and presents about applications of optical fiber biosensors. Discussions on the trends in optical fiber biosensor applications in real samples are enumerated.

  7. Multimode optical fiber

    Science.gov (United States)

    Bigot-Astruc, Marianne; Molin, Denis; Sillard, Pierre

    2014-11-04

    A depressed graded-index multimode optical fiber includes a central core, an inner depressed cladding, a depressed trench, an outer depressed cladding, and an outer cladding. The central core has an alpha-index profile. The depressed claddings limit the impact of leaky modes on optical-fiber performance characteristics (e.g., bandwidth, core size, and/or numerical aperture).

  8. Optical Fiber Spectroscopy

    Science.gov (United States)

    Buoncristiani, A. M.

    1999-01-01

    This is the final report of work done on NASA Grant NAG-1-443. The work covers the period from July 1, 1992 to December 1, 1998. During this period several distinct but related research studies and work tasks were undertaken. These different subjects are enumerated below with a description of the work done on each of them. The focus of the research was the development of optical fibers for use as distributed temperature and stress sensors. The initial concept was to utilize the utilize the temperature and stress dependence of emission from rare earth and transition metal ions substitutionally doped into crystalline or glass fibers. During the course of investigating this it became clear that fiber Bragg gratings provided a alternative for making the desired measurements and there was a shift of research focus on to include the photo-refractive properties of germano-silicate glasses used for most gratings and to the possibility of developing fiber laser sources for an integrated optical sensor in the research effort. During the course of this work several students from Christopher Newport University and other universities participated in this effort. Their names are listed below. Their participation was an important part of their education.

  9. Distributed optical fiber temperature sensor (DOFTS) system applied to automatic temperature alarm of coal mine and tunnel

    Science.gov (United States)

    Zhang, Zaixuan; Wang, Kequan; Kim, Insoo S.; Wang, Jianfeng; Feng, Haiqi; Guo, Ning; Yu, Xiangdong; Zhou, Bangquan; Wu, Xiaobiao; Kim, Yohee

    2000-05-01

    The DOFTS system that has applied to temperature automatically alarm system of coal mine and tunnel has been researched. It is a real-time, on line and multi-point measurement system. The wavelength of LD is 1550 nm, on the 6 km optical fiber, 3000 points temperature signal is sampled and the spatial position is certain. Temperature measured region: -50 degree(s)C--100 degree(s)C; measured uncertain value: +/- 3 degree(s)C; temperature resolution: 0.1 degree(s)C; spatial resolution: test, test content and practical test results have been discussed.

  10. Aqueous contaminant detection via UiO-66 thin film optical fiber sensor platform with fast Fourier transform based spectrum analysis

    Science.gov (United States)

    Nazari, Marziyeh; Rubio-Martinez, Marta; Babarao, Ravichandar; Ayad Younis, Adel; Collins, Stephen F.; Hill, Matthew R.; Duke, Mikel C.

    2018-01-01

    Routine water quality monitoring is required in drinking and waste water management. A particular interest is to measure concentrations of a range of diverse contaminants on-site or remotely in real time. Here we present metal organic framework (MOF) integrated optical fiber sensor that allows for rapid optical measurement based on fast Fourier transform (FFT) spectrum analysis. The end-face of these glass optical fibers was modified with UiO-66(Zr) MOF thin film by in situ hydrothermal synthesis for the detection of the model contaminants, Rhodamine-B and 4-Aminopyridine, in water. The sensing mechanism is based on the change in the optical path length of the thin film induced by the adsorption of chemical molecules by UiO-66. Using FFT analysis, various modes of interaction (physical and chemical) became apparent, showing both irreversible changes upon contact with the contaminant, as well as reversible changes according to actual concentration. This was indicated by the second harmonic elevation to a certain level translating to high sensitivity detection.

  11. Optical fiber spectrophotometer

    International Nuclear Information System (INIS)

    Zhuang Weixin; Tian Guocheng; Ye Guoan; Zhou Zhihong; Cheng Weiwei; Huang Lifeng; Liu Suying; Tang Yanji; Hu Jingxin; Zhao Yonggang

    1998-12-01

    A method called 'Two Arm's Photo out and Electricity Send-back' is introduced. UV-365 UV/VIS/NIR spectrophotometer has been reequipped by this way with 5 meters long optical fiber. Another method called 'One Arm's Photo out and Photo Send-back' is also introduced. λ 19 UV/VIS/NIR spectrophotometer has been reequipped by this way with 10 meters long optical fiber. Optical fiber spectrophotometer can work as its main set. So it is particularly applicable to radio activity work

  12. Applications research in ultrasonic testing of carbon fiber composite based on an optical fiber F-p sensor

    Science.gov (United States)

    Shan, Ning

    2016-10-01

    Carbon fiber composite is widely applied to the field of aerospace engineering because of its excellent performance. But it will be able to form more defects in the process of manufacturing inevitably on account of unique manufacturing process. Meanwhile it has sophisticated structure and services in the bad environment long time. The existence of defects will be able to cause the sharp decline in component's performance when the defect accumulates to a certain degree. So the reliability and safety test demand of carbon fiber composite is higher and higher. Ultrasonic testing technology is the important means used for characteristics of component inspection of composite materials. Ultrasonic information detection uses acoustic transducer generally. It need coupling agent and is higher demand for the surface of sample. It has narrow frequency band and low test precision. The extrinsic type optical fiber F-P interference cavity structure is designed to this problem. Its optical interference model is studied. The initial length of F-P cavity is designed. The realtime online detection system of carbon fiber composite is established based on optical fiber F-P Ultrasound sensing technology. Finally, the testing experiment study is conducted. The results show that the system can realize real-time online detection of carbon fiber composite's defect effectively. It operates simply and realizes easily. It has low cost and is easy to practical engineering.

  13. Metal-coated optical fibers for high temperature sensing applications

    Science.gov (United States)

    Fidelus, Janusz D.; Wysokiński, Karol; Stańczyk, Tomasz; Kołakowska, Agnieszka; Nasiłowski, Piotr; Lipiński, Stanisław; Tenderenda, Tadeusz; Nasiłowski, Tomasz

    2017-10-01

    An novel low-temperature method was used to enhance the corrosion resistance of copper or gold-coated optical fibers. A characterization of the elaborated materials and reports on selected studies such as cyclic temperature tests together with tensile tests is presented. Gold-coated optical fibers are proposed as a component of optical fiber sensors working in oxidizing atmospheres under temperatures exceeding 900 °C.

  14. Dynamic Characterization of Polymer Optical Fibers

    DEFF Research Database (Denmark)

    Stefani, Alessio; Andresen, Søren; Yuan, Wu

    2012-01-01

    With the increasing interest in fiber sensors based on polymer optical fibers, it becomes fundamental to determine the real applicability and reliability of this type of sensor. The viscoelastic nature of polymers gives rise to questions about the mechanical behavior of the fibers. In particular...

  15. Localized surface plasmon resonance with five-branched gold nanostars in a plastic optical fiber for bio-chemical sensor implementation.

    Science.gov (United States)

    Cennamo, Nunzio; D'Agostino, Girolamo; Donà, Alice; Dacarro, Giacomo; Pallavicini, Piersandro; Pesavento, Maria; Zeni, Luigi

    2013-10-29

    In this paper a refractive index sensor based on localized surface plasmon resonance (LSPR) in a Plastic Optical Fiber (POF), is presented and experimentally tested. LSPR is achieved exploiting five-branched gold nanostars (GNS) obtained using Triton X-100 in a seed-growth synthesis. They have the uncommon feature of three localized surface plasmon resonances. The strongest LSPRs fall in two ranges, one in the 600-900 nm range (LSPR 2) and the other one in the 1,100-1,600 nm range (LSPR 3), both sensible to refractive index changes. Anyway, due to the extremely strong attenuation (>10(2) dB/m) of the employed POF in the 1,100-1,600 nm range, only LSPR 2 will be exploited for refractive index change measurements, useful for bio-chemical sensing applications, as a proof of principle of the possibility of realizing a compact, low cost and easy-to-use GNS based device.

  16. Optical fiber end-facet polymer suspended-mirror devices

    Science.gov (United States)

    Yao, Mian; Wu, Jushuai; Zhang, A. Ping; Tam, Hwa-Yaw; Wai, P. K. A.

    2017-04-01

    This paper presents a novel optical fiber device based on a polymer suspended mirror on the end facet of an optical fiber. With an own-developed optical 3D micro-printing technology, SU-8 suspended-mirror devices (SMDs) were successfully fabricated on the top of a standard single-mode optical fiber. Optical reflection spectra of the fabricated SU- 8 SMDs were measured and compared with theoretical analysis. The proposed technology paves a way towards 3D microengineering of the small end-facet of optical fibers to develop novel fiber-optic sensors.

  17. Optical fibers and their instrumentation applications

    International Nuclear Information System (INIS)

    Boisde, Gilbert.

    1982-09-01

    The use of optical fibers in instrumentation requires a knowledge of their properties as ''photon carriers'' and ''sensors''. New instrumentation design implies a satisfactory evaluation of the entire measurement circuit, including the emitter, optical coupling, optical fiber with its physical, spectral and physico-chemical properties, the connector, receiver, signal amplifier and data processing system. An example, is provided of the development of a new technique in physico-chemical instrumentation: remote spectrophotometry. Three aspects are discussed: 1) industrial measurement in ''process control'' using the Telephot (R), 2) remote spectral measurement, 3) opical multiplexing. This is followed by a review of various optical fiber based instrumental techniques used in the fields of medicine (endoscopy, fluorothermy, laser surgery), solar energy industrial applications subject to electrical disturbances (position sensors, strain measurements), and in physico-chemical analysis (fluorescence, redox potentials) [fr

  18. Optical fiber switch

    Science.gov (United States)

    Early, James W.; Lester, Charles S.

    2002-01-01

    Optical fiber switches operated by electrical activation of at least one laser light modulator through which laser light is directed into at least one polarizer are used for the sequential transport of laser light from a single laser into a plurality of optical fibers. In one embodiment of the invention, laser light from a single excitation laser is sequentially transported to a plurality of optical fibers which in turn transport the laser light to separate individual remotely located laser fuel ignitors. The invention can be operated electro-optically with no need for any mechanical or moving parts, or, alternatively, can be operated electro-mechanically. The invention can be used to switch either pulsed or continuous wave laser light.

  19. Optical Fiber Fusion Splicing

    CERN Document Server

    Yablon, Andrew D

    2005-01-01

    This book is an up-to-date treatment of optical fiber fusion splicing incorporating all the recent innovations in the field. It provides a toolbox of general strategies and specific techniques that the reader can apply when optimizing fusion splices between novel fibers. It specifically addresses considerations important for fusion splicing of contemporary specialty fibers including dispersion compensating fiber, erbium-doped gain fiber, polarization maintaining fiber, and microstructured fiber. Finally, it discusses the future of optical fiber fusion splicing including silica and non-silica based optical fibers as well as the trend toward increasing automation. Whilst serving as a self-contained reference work, abundant citations from the technical literature will enable readers to readily locate primary sources.

  20. Optical fiber stripper positioning apparatus

    Science.gov (United States)

    Fyfe, Richard W.; Sanchez, Jr., Amadeo

    1990-01-01

    An optical fiber positioning apparatus for an optical fiber stripping device is disclosed which is capable of providing precise axial alignment between an optical fiber to be stripped of its outer jacket and the cutting blades of a stripping device. The apparatus includes a first bore having a width approximately equal to the diameter of an unstripped optical fiber and a counter bore axially aligned with the first bore and dimensioned to precisely receive a portion of the stripping device in axial alignment with notched cutting blades within the stripping device to thereby axially align the notched cutting blades of the stripping device with the axis of the optical fiber to permit the notched cutting blades to sever the jacket on the optical fiber without damaging the cladding on the optical fiber. In a preferred embodiment, the apparatus further includes a fiber stop which permits determination of the length of jacket to be removed from the optical fiber.

  1. Distributed Optical Fiber Sensors with Ultrafast Laser Enhanced Rayleigh Backscattering Profiles for Real-Time Monitoring of Solid Oxide Fuel Cell Operations.

    Science.gov (United States)

    Yan, Aidong; Huang, Sheng; Li, Shuo; Chen, Rongzhang; Ohodnicki, Paul; Buric, Michael; Lee, Shiwoo; Li, Ming-Jun; Chen, Kevin P

    2017-08-24

    This paper reports a technique to enhance the magnitude and high-temperature stability of Rayleigh back-scattering signals in silica fibers for distributed sensing applications. With femtosecond laser radiation, more than 40-dB enhancement of Rayleigh backscattering signal was generated in silica fibers using 300-nJ laser pulses at 250 kHz repetition rate. The laser-induced Rayleigh scattering defects were found to be stable from the room temperature to 800 °C in hydrogen gas. The Rayleigh scatter at high temperatures was correlated to the formation and modification of nanogratings in the fiber core. Using optical fibers with enhanced Rayleigh backscattering profiles as distributed temperature sensors, we demonstrated real-time monitoring of solid oxide fuel cell (SOFC) operations with 5-mm spatial resolution at 800 °C. Information gathered by these fiber sensor tools can be used to verify simulation results or operated in a process-control system to improve the operational efficiency and longevity of SOFC-based energy generation systems.

  2. Photochemical properties and sensor applications of modified yellow fluorescent protein (YFP) covalently attached to the surfaces of etched optical fibers (EOFs).

    Science.gov (United States)

    Veselov, Alexey A; Abraham, Bobin George; Lemmetyinen, Helge; Karp, Matti T; Tkachenko, Nikolai V

    2012-01-01

    Fluorescent proteins have the inherent ability to act as sensing components which function both in vitro and inside living cells. We describe here a novel study on a covalent site-specific bonding of fluorescent proteins to form self-assembled monolayers (SAMs) on the surface of etched optical fibers (EOFs). Deposition of fluorescent proteins on EOFs gives the opportunity to increase the interaction of guided light with deposited molecules relative to plane glass surfaces. The EOF modification is carried out by surface activation using 3-aminopropylthrimethoxysilane (APTMS) and bifunctional crosslinker sulfosuccinimidyl 4-[N-maleimidomethyl]cyclohexane-1-carboxylate (sulfo-SMCC) which exposes sulfhydryl-reactive maleimide groups followed by covalent site-specific coupling of modified yellow fluorescent protein (YFP). Steady-state and fluorescence lifetime measurements confirm the formation of SAM. The sensor applications of YPF SAMs on EOF are demonstrated by the gradual increase of emission intensity upon addition of Ca(2+) ions in the concentration range from a few tens of micromolars up to a few tens of millimolars. The studies on the effect of pH, divalent cations, denaturing agents, and proteases reveal the stability of YFP on EOFs at normal physiological conditions. However, treatments with 0.5% SDS at pH 8.5 and protease trypsin are found to denaturate or cleave the YFP from fiber surfaces.

  3. Localized Surface Plasmon Resonance with Five-Branched Gold Nanostars in a Plastic Optical Fiber for Bio-Chemical Sensor Implementation

    Science.gov (United States)

    Cennamo, Nunzio; D'Agostino, Girolamo; Donà, Alice; Dacarro, Giacomo; Pallavicini, Piersandro; Pesavento, Maria; Zeni, Luigi

    2013-01-01

    In this paper a refractive index sensor based on localized surface plasmon resonance (LSPR) in a Plastic Optical Fiber (POF), is presented and experimentally tested. LSPR is achieved exploiting five-branched gold nanostars (GNS) obtained using Triton X-100 in a seed-growth synthesis. They have the uncommon feature of three localized surface plasmon resonances. The strongest LSPRs fall in two ranges, one in the 600–900 nm range (LSPR 2) and the other one in the 1,100–1,600 nm range (LSPR 3), both sensible to refractive index changes. Anyway, due to the extremely strong attenuation (>102 dB/m) of the employed POF in the 1,100–1,600 nm range, only LSPR 2 will be exploited for refractive index change measurements, useful for bio-chemical sensing applications, as a proof of principle of the possibility of realizing a compact, low cost and easy-to-use GNS based device. PMID:24172284

  4. Localized Surface Plasmon Resonance with Five-Branched Gold Nanostars in a Plastic Optical Fiber for Bio-Chemical Sensor Implementation

    Directory of Open Access Journals (Sweden)

    Luigi Zeni

    2013-10-01

    Full Text Available In this paper a refractive index sensor based on localized surface plasmon resonance (LSPR in a Plastic Optical Fiber (POF, is presented and experimentally tested. LSPR is achieved exploiting five-branched gold nanostars (GNS obtained using Triton X-100 in a seed-growth synthesis. They have the uncommon feature of three localized surface plasmon resonances. The strongest LSPRs fall in two ranges, one in the 600–900 nm range (LSPR 2 and the other one in the 1,100–1,600 nm range (LSPR 3, both sensible to refractive index changes. Anyway, due to the extremely strong attenuation (>102 dB/m of the employed POF in the 1,100–1,600 nm range, only LSPR 2 will be exploited for refractive index change measurements, useful for bio-chemical sensing applications, as a proof of principle of the possibility of realizing a compact, low cost and easy-to-use GNS based device.

  5. Optical fiber communications

    CERN Document Server

    Keiser, Gerd

    2008-01-01

    The fourth edition of this popular text and reference book presents the fundamental principles for understanding and applying optical fiber technology to sophisticated modern telecommunication systems. Optical-fiber-based telecommunication networks have become a major information-transmission-system, with high capacity links encircling the globe in both terrestrial and undersea installations. Numerous passive and active optical devices within these links perform complex transmission and networking functions in the optical domain, such as signal amplification, restoration, routing, and switching. Along with the need to understand the functions of these devices comes the necessity to measure both component and network performance, and to model and stimulate the complex behavior of reliable high-capacity networks.

  6. Superlattice Microstructured Optical Fiber

    Science.gov (United States)

    Tse, Ming-Leung Vincent; Liu, Zhengyong; Cho, Lok-Hin; Lu, Chao; Wai, Ping-Kong Alex; Tam, Hwa-Yaw

    2014-01-01

    A generic three-stage stack-and-draw method is demonstrated for the fabrication of complex-microstructured optical fibers. We report the fabrication and characterization of a silica superlattice microstructured fiber with more than 800 rhomboidally arranged air-holes. A polarization-maintaining fiber with a birefringence of 8.5 × 10−4 is demonstrated. The birefringent property of the fiber is found to be highly insensitive to external environmental effects, such as pressure. PMID:28788693

  7. Absorption-Modulated Crossed-Optical Fiber-Sensor Platform for Measurements in Liquid Environments and Flow Streams

    Directory of Open Access Journals (Sweden)

    Paul E. Henning

    2017-01-01

    Full Text Available A new evanescent-wave fiber sensor is described that utilizes absorption-modulated luminescence (AML in combination with a crossed-fiber sensor platform. The luminescence signals of two crossed-fiber reference regions, placed on opposite sides of the stretch of fiber supporting the absorbance sensor, monitor the optical intensity in the fiber core. Evanescent absorption of the sensor reduces a portion of the excitation light and modulates the luminescence of the second reference region. The attenuation is determined from the luminescence intensity of both reference regions similar to the Beer-Lambert Law. The AML-Crossed-Fiber technique was demonstrated using the absorbance of the Zn(II-PAN2 complex at 555 nm. A linear response was obtained over a zinc(II concentration range of 0 to 20 μM (approximately 0 to 1.3 ppm. A nonlinear response was observed at higher zinc(II concentrations and was attributed to depletion of higher-order modes in the fiber. This was corroborated by the measured induced repopulation of these modes.

  8. Note: Optical fiber milled by focused ion beam and its application for Fabry-Pérot refractive index sensor

    DEFF Research Database (Denmark)

    Yuan, Scott Wu; Wang, Fei; Savenko, Alexey

    2011-01-01

    We introduce a highly compact fiber-optic Fabry-Pérot refractive index sensor integrated with a fluid channel that is fabricated directly near the tip of a 32 μm in diameter single-mode fiber taper. The focused ion beam technique is used to efficiently mill the microcavity from the fiber side...... and finely polish the end facets of the cavity with a high spatial resolution. It is found that a fringe visibility of over 15 dB can be achieved and that the sensor has a sensitivity of ∼1731 nm/RIU (refractive index units) and a detection limit of ∼5.78 × 10−6 RIU. This miniature integrated all-in-fiber...

  9. Optical fiber-applied radiation detection system

    International Nuclear Information System (INIS)

    Nishiura, Ryuichi; Uranaka, Yasuo; Izumi, Nobuyuki

    2001-01-01

    A technique to measure radiation by using plastic scintillation fibers doped radiation fluorescent (scintillator) to plastic optical fiber for a radiation sensor, was developed. The technique contains some superiority such as high flexibility due to using fibers, relatively easy large area due to detecting portion of whole of fibers, and no electromagnetic noise effect due to optical radiation detection and signal transmission. Measurable to wide range of and continuous radiation distribution along optical fiber cable at a testing portion using scintillation fiber and flight time method, the optical fiber-applied radiation sensing system can effectively monitor space radiation dose or apparatus operation condition monitoring. And, a portable type scintillation optical fiber body surface pollution monitor can measure pollution concentration of radioactive materials attached onto body surface by arranging scintillation fiber processed to a plate with small size and flexibility around a man to be tested. Here were described on outline and fundamental properties of various application products using these plastic scintillation fiber. (G.K.)

  10. Thermo-optic characteristic of DNA thin solid film and its application as a biocompatible optical fiber temperature sensor.

    Science.gov (United States)

    Hong, Seongjin; Jung, Woohyun; Nazari, Tavakol; Song, Sanggwon; Kim, Taeoh; Quan, Chai; Oh, Kyunghwan

    2017-05-15

    We report unique thermo-optical characteristics of DNA-Cetyl tri-methyl ammonium (DNA-CTMA) thin solid film with a large negative thermo-optical coefficient of -3.4×10-4/°C in the temperature range from 20°C to 70°C without any observable thermal hysteresis. By combining this thermo-optic DNA film and fiber optic multimode interference (MMI) device, we experimentally demonstrated a highly sensitive compact temperature sensor with a large spectral shift of 0.15 nm/°C. The fiber optic MMI device was a concatenated structure with single-mode fiber (SMF)-coreless silica fiber (CSF)-single mode fiber (SMF) and the DNA-CTMA film was deposited on the CSF. The spectral shifts of the device in experiments were compared with the beam propagation method, which showed a good agreement.

  11. Biosensing with optical fiber gratings

    Science.gov (United States)

    Chiavaioli, Francesco; Baldini, Francesco; Tombelli, Sara; Trono, Cosimo; Giannetti, Ambra

    2017-06-01

    Optical fiber gratings (OFGs), especially long-period gratings (LPGs) and etched or tilted fiber Bragg gratings (FBGs), are playing an increasing role in the chemical and biochemical sensing based on the measurement of a surface refractive index (RI) change through a label-free configuration. In these devices, the electric field evanescent wave at the fiber/surrounding medium interface changes its optical properties (i.e. intensity and wavelength) as a result of the RI variation due to the interaction between a biological recognition layer deposited over the fiber and the analyte under investigation. The use of OFG-based technology platforms takes the advantages of optical fiber peculiarities, which are hardly offered by the other sensing systems, such as compactness, lightness, high compatibility with optoelectronic devices (both sources and detectors), and multiplexing and remote measurement capability as the signal is spectrally modulated. During the last decade, the growing request in practical applications pushed the technology behind the OFG-based sensors over its limits by means of the deposition of thin film overlays, nanocoatings, and nanostructures, in general. Here, we review efforts toward utilizing these nanomaterials as coatings for high-performance and low-detection limit devices. Moreover, we review the recent development in OFG-based biosensing and identify some of the key challenges for practical applications. While high-performance metrics are starting to be achieved experimentally, there are still open questions pertaining to an effective and reliable detection of small molecules, possibly up to single molecule, sensing in vivo and multi-target detection using OFG-based technology platforms.

  12. Biosensing with optical fiber gratings

    Directory of Open Access Journals (Sweden)

    Chiavaioli Francesco

    2017-06-01

    Full Text Available Optical fiber gratings (OFGs, especially long-period gratings (LPGs and etched or tilted fiber Bragg gratings (FBGs, are playing an increasing role in the chemical and biochemical sensing based on the measurement of a surface refractive index (RI change through a label-free configuration. In these devices, the electric field evanescent wave at the fiber/surrounding medium interface changes its optical properties (i.e. intensity and wavelength as a result of the RI variation due to the interaction between a biological recognition layer deposited over the fiber and the analyte under investigation. The use of OFG-based technology platforms takes the advantages of optical fiber peculiarities, which are hardly offered by the other sensing systems, such as compactness, lightness, high compatibility with optoelectronic devices (both sources and detectors, and multiplexing and remote measurement capability as the signal is spectrally modulated. During the last decade, the growing request in practical applications pushed the technology behind the OFG-based sensors over its limits by means of the deposition of thin film overlays, nanocoatings, and nanostructures, in general. Here, we review efforts toward utilizing these nanomaterials as coatings for high-performance and low-detection limit devices. Moreover, we review the recent development in OFG-based biosensing and identify some of the key challenges for practical applications. While high-performance metrics are starting to be achieved experimentally, there are still open questions pertaining to an effective and reliable detection of small molecules, possibly up to single molecule, sensing in vivo and multi-target detection using OFG-based technology platforms.

  13. Optical fibers for FTTH application

    Science.gov (United States)

    Guzowski, Bartlomiej; Tosik, Grzegorz; Lisik, Zbigniew; Bedyk, Michal; Kubiak, Andrzej

    2013-07-01

    In this paper the specifics of FTTH (Fiber To The Home) networks in terms of requirements for optical fibers has been presented. Optical fiber samples used in FTTH applications acquired from the worldwide leading manufacturers were subjected to small diameter mandrel wraps tests. The detailed procedures of performed tests and the measurement results has been presented.

  14. Chemistry Research of Optical Fibers.

    Science.gov (United States)

    1982-09-27

    BROADENING IN OPTICAL FIBERS Herbert B. Rosenstock* Naval Research Laboratory Washington, DC 20375 ABSTRACT A light pulse transmitted through a fiber...Marcatili, Marcuse , and Personick, "Dispersion Properties of Fibers" (Ch. 4 in "Optical Fiber Telecommunications," S. E. Miller and A. C. Chynoweth, eds

  15. Optical-fiber interferometer for velocity measurements with picosecond resolution

    International Nuclear Information System (INIS)

    Weng Jidong; Tan Hua; Wang Xiang; Ma Yun; Hu Shaolou; Wang Xiaosong

    2006-01-01

    The conventional Doppler laser-interference velocimeters are made up of traditional optical elements such as lenses and mirrors and will generally restrict its applications in multipoint velocity measurements. By transfering the light from multimode optical fiber to single-mode optical fiber and using the currently available conventional telecommunications elements, the authors have constructed a velocimeter called all-fiber displacement interferometer system for any reflector. The unique interferometer system is only made up of fibers or fiber-coupled components. The viability of this technique is demonstrated by measuring the velocity of an interface moving at velocity of 2133 m/s with 50 ps time resolution. In addition, the concept of optical-fiber mode conversion would provide a way to develop various optical-fiber sensors

  16. Photometric device using optical fibers

    International Nuclear Information System (INIS)

    Boisde, Gilbert; Perez, J.-J.

    1981-02-01

    Remote measurements in radioactive environment are now possible with optical fibers. Measurement instruments developed by CEA are constitued of: - an optical probe (5 mm to 1 meter optical path length), - a photometric measurement device, - optical fiber links. 'TELEPHOT' is a photometric device for industrial installations. It is uses interferentiel filters for 2 to 5 simultaneous wave lengths. 'CRUDMETER' measures the muddiness of water. It can be equipped with a high sensitivity cell of 50 cm optical path length tested up to 250 bars. Coupling a double beam spectrophotometer to a remote optical probe, up to 1 meter optical path length, is carried out by means of an optical device using optical fibers links, eventually several hundred meter long. For these equipments special step index large core fibers, 1 to 1.5 mm in diameter, have been developed as well connectors. For industrial control and research these instruments offer new prospect thanks to optical fibers use [fr

  17. Anisotropic elliptic optical fibers

    Science.gov (United States)

    Kang, Soon Ahm

    1991-05-01

    The exact characteristic equation for an anisotropic elliptic optical fiber is obtained for odd and even hybrid modes in terms of infinite determinants utilizing Mathieu and modified Mathieu functions. A simplified characteristic equation is obtained by applying the weakly guiding approximation such that the difference in the refractive indices of the core and the cladding is small. The simplified characteristic equation is used to compute the normalized guide wavelength for an elliptical fiber. When the anisotropic parameter is equal to unity, the results are compared with the previous research and they are in close agreement. For a fixed value normalized cross-section area or major axis, the normalized guide wavelength lambda/lambda(sub 0) for an anisotropic elliptic fiber is small for the larger value of anisotropy. This condition indicates that more energy is carried inside of the fiber. However, the geometry and anisotropy of the fiber have a smaller effect when the normalized cross-section area is very small or very large.

  18. Optical fiber inspection system

    Science.gov (United States)

    Moore, Francis W.

    1987-01-01

    A remote optical inspection system including an inspection head. The inspection head has a passageway through which pellets or other objects are passed. A window is provided along the passageway through which light is beamed against the objects being inspected. A plurality of lens assemblies are arranged about the window so that reflected light can be gathered and transferred to a plurality of coherent optical fiber light guides. The light guides transfer the light images to a television or other image transducer which converts the optical images into a representative electronic signal. The electronic signal can then be displayed on a signal viewer such as a television monitor for inspection by a person. A staging means can be used to support the objects for viewing through the window. Routing means can be used to direct inspected objects into appropriate exit passages for accepted or rejected objects. The inspected objects are advantageously fed in a singular manner to the staging means and routing means. The inspection system is advantageously used in an enclosure when toxic or hazardous materials are being inspected.

  19. Fundamentals of plastic optical fibers

    CERN Document Server

    Koike, Yasuhiro

    2014-01-01

    Polymer photonics is an interdisciplinary field which demands excellence both in optics (photonics) and materials science (polymer). However, theses disciplines have developed independently, and therefore the demand for a comprehensive work featuring the fundamentals of photonic polymers is greater than ever.This volume focuses on Polymer Optical Fiber and their applications. The first part of the book introduces typical optical fibers according to their classifications of material, propagating mode, and structure. Optical properties, the high bandwidth POF and transmission loss are discussed,

  20. Optofluidic refractive-index sensors employing bent waveguide structures for low-cost, rapid chemical and biomedical sensing.

    Science.gov (United States)

    Liu, I-Chen; Chen, Pin-Chuan; Chau, Lai-Kwan; Chang, Guo-En

    2018-01-08

    We propose and develop an intensity-detection-based refractive-index (RI) sensor for low-cost, rapid RI sensing. The sensor is composed of a polymer bent ridge waveguide (BRWG) structure on a low-cost glass substrate and is integrated with a microfluidic channel. Different-RI solutions flowing through the BRWG sensing region induce output optical power variations caused by optical bend losses, enabling simple and real-time RI detection. Additionally, the sensors are fabricated using rapid and cost-effective vacuum-less processes, attaining the low cost and high throughput required for mass production. A good RI solution of 5.31 10 -4 × RIU -1 is achieved from the RI experiments. This study demonstrates mass-producible and compact RI sensors for rapid and sensitive chemical analysis and biomedical sensing.

  1. Experimental demonstration of a simple displacement sensor based on a bent single-mode–multimode–single-mode fiber structure

    International Nuclear Information System (INIS)

    Wu, Qiang; Semenova, Yuliya; Wang, Pengfei; Hatta, Agus Muhamad; Farrell, Gerald

    2011-01-01

    A simple displacement sensor based on a bent single-mode–multimode–single-mode (SMS) fiber structure is proposed and experimentally investigated. The sensor offers a wider displacement range, not limited by the risk of fiber breakage, as well as a three-fold increase in displacement sensitivity by comparison with a straight SMS structure sensor. This sensor can be interrogated by either an optical spectral analyzer (OSA) or a ratiometric interrogation system: (1) if interrogated by an OSA assuming a resolution of 1 pm, it has a sensitivity of 28.2 nm for a displacement measurement range from 0 to 280 µm; (2) if interrogated by a ratiometric interrogation system, it has worst and best case resolutions of 556 and 38 nm, respectively, for a displacement measurement range from 0 to 520 µm

  2. Multi-antibody biosensing with Topas microstructured polymer optical fiber

    DEFF Research Database (Denmark)

    Emiliyanov, Grigoriy Andreev; Bang, Ole; Hoiby, Poul E.

    We present a Topas based microstructured polymer optical fiber multi-antibody biosensor. This polymer allows localized activation of sensor layers on the inner side of the air holes. This concept is used to create two different sensor sections in the same fiber. Simultaneous detection of two kinds...

  3. Structural Health Monitoring of Civil Infrastructure Using Optical Fiber Sensing Technology: A Comprehensive Review

    Science.gov (United States)

    Ye, X. W.; Su, Y. H.; Han, J. P.

    2014-01-01

    In the last two decades, a significant number of innovative sensing systems based on optical fiber sensors have been exploited in the engineering community due to their inherent distinctive advantages such as small size, light weight, immunity to electromagnetic interference (EMI) and corrosion, and embedding capability. A lot of optical fiber sensor-based monitoring systems have been developed for continuous measurement and real-time assessment of diversified engineering structures such as bridges, buildings, tunnels, pipelines, wind turbines, railway infrastructure, and geotechnical structures. The purpose of this review article is devoted to presenting a summary of the basic principles of various optical fiber sensors, innovation in sensing and computational methodologies, development of novel optical fiber sensors, and the practical application status of the optical fiber sensing technology in structural health monitoring (SHM) of civil infrastructure. PMID:25133250

  4. Structural health monitoring of civil infrastructure using optical fiber sensing technology: a comprehensive review.

    Science.gov (United States)

    Ye, X W; Su, Y H; Han, J P

    2014-01-01

    In the last two decades, a significant number of innovative sensing systems based on optical fiber sensors have been exploited in the engineering community due to their inherent distinctive advantages such as small size, light weight, immunity to electromagnetic interference (EMI) and corrosion, and embedding capability. A lot of optical fiber sensor-based monitoring systems have been developed for continuous measurement and real-time assessment of diversified engineering structures such as bridges, buildings, tunnels, pipelines, wind turbines, railway infrastructure, and geotechnical structures. The purpose of this review article is devoted to presenting a summary of the basic principles of various optical fiber sensors, innovation in sensing and computational methodologies, development of novel optical fiber sensors, and the practical application status of the optical fiber sensing technology in structural health monitoring (SHM) of civil infrastructure.

  5. Structural Health Monitoring of Civil Infrastructure Using Optical Fiber Sensing Technology: A Comprehensive Review

    Directory of Open Access Journals (Sweden)

    X. W. Ye

    2014-01-01

    Full Text Available In the last two decades, a significant number of innovative sensing systems based on optical fiber sensors have been exploited in the engineering community due to their inherent distinctive advantages such as small size, light weight, immunity to electromagnetic interference (EMI and corrosion, and embedding capability. A lot of optical fiber sensor-based monitoring systems have been developed for continuous measurement and real-time assessment of diversified engineering structures such as bridges, buildings, tunnels, pipelines, wind turbines, railway infrastructure, and geotechnical structures. The purpose of this review article is devoted to presenting a summary of the basic principles of various optical fiber sensors, innovation in sensing and computational methodologies, development of novel optical fiber sensors, and the practical application status of the optical fiber sensing technology in structural health monitoring (SHM of civil infrastructure.

  6. Critical review of pH sensing with optical fibers

    Science.gov (United States)

    Baldini, Francesco

    1999-02-01

    The chemical parameter most investigated with optical fibers is doubtless pH. The first pH optical fiber sensor was described in 1980. Since then, more than one hundred and twenty original papers describing different pH sensors have been published, based on absorption-based indicators on fluorophores. Such interest is perfectly justified, since pH detection is essential in many fields of application, ranging from the environment and medicine to industry and process control. Moreover, pH transduction can be used for measuring different chemical species, such as carbon dioxide, ammonia and pesticides. Notwithstanding the great number of prototypes realized in different laboratories all over the world, only a few products are available on the market. A critical analysis of the state of art in pH sensing using optical fibers is described, outlining the advantages and disadvantages of an optical approach.

  7. Optical fiber sensors for image formation in radiodiagnostic - preliminary essays; Sensores a fibra optica para formacao de imagens em radiodiagnostico - ensaios preliminares

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Cesar C. de; Werneck, Marcelo M. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Biomedica

    1998-07-01

    This work describes preliminary experiments that will bring subsidies to analyze the capability to implement a system able to capture radiological images with new sensor system, comprised by FOs scanning process and I-CCD camera. These experiments have the main objective to analyze the optical response from FOs bundle, with several typos of scintillators associated with them, when it is submitted to medical x-rays exposition. (author)

  8. Viscoelastic limit of polymer optical fibers: characterization of the dynamic response

    DEFF Research Database (Denmark)

    Stefani, Alessio; Yuan, Scott Wu; Andresen, S.

    2011-01-01

    Characterization of polymer optical fibers (POFs) in terms of dynamic behavior is important for many sensors applications for which this type of fibers offers big advantages. We report measurements of the Young’s modulus on microstructured and step index polymer optical fibers and their comparison...

  9. Interferometric optical fiber microcantilever beam biosensor

    Science.gov (United States)

    Wavering, Thomas A.; Meller, Scott A.; Evans, Mishell K.; Pennington, Charles; Jones, Mark E.; VanTassell, Roger; Murphy, Kent A.; Velander, William H.; Valdes, E.

    2000-12-01

    With the proliferation of biological weapons, the outbreak of food poisoning occurrences, and the spread of antibiotic resistant strains of pathogenic bacteria, the demand has arisen for portable systems capable of rapid, specific, and quantitative target detection. The ability to detect minute quantities of targets will provide the means to quickly assess a health hazardous situation so that the appropriate response can be orchestrated. Conventional test results generally require hours or even several days to be reported, and there is no change for real-time feedback. An interferometric optical fiber microcantilever beam biosensor has successfully demonstrated real time detection of target molecules. The microcantilever biosensor effectively combines advanced technology from silicon micromachining, optical fiber sensor, and biochemistry to create a novel detection device. This approach utilizes affinity coatings on micromachiend cantilever beams to attract target molecules. The presence of the target molecule causes bending in the cantilever beam, which is monitored using an optical displacement system. Dose-response trials have shown measured responses at nanogram/ml concentrations of target molecules. Sensitivity is expected to extend from the nanogram to the picogram range of total captured mass as the microcantilever sensors are optimized.

  10. Influence of the optical fiber type on the performances of fiber-optics current sensor dedicated to plasma current measurement in ITER.

    Science.gov (United States)

    Aerssens, Matthieu; Descamps, Frédéric; Gusarov, Andrei; Mégret, Patrice; Moreau, Philippe; Wuilpart, Marc

    2015-07-01

    In this paper, we compare, by means of simulations using the Jones formalism, the performances of several optical fiber types (low birefringence and spun fibers) for the measurement of plasma current in international thermonuclear experimental reactor (ITER). The main results presented in this paper concern the minimum value of the ratio between the beat length and the spun period, which allows meeting the ITER current measurement specifications. Assuming a high-birefringence spun fiber with a beat length of 3 mm, we demonstrate that the minimum ratio between the beat length and the spun period is 4.4 when considering a 28 m long sensing fiber surrounding the vacuum vessel. This minimum ratio rises to 10.14 when a 100 m long lead fiber connecting the interrogating system to the sensing fiber is taken into account.

  11. Measurement of peak temperature along an optical fiber

    International Nuclear Information System (INIS)

    Fox, R.J.

    1983-01-01

    A multimode silica-clad optical fiber with a liquid silicone core was used as a distributed-line peak-temperature sensor over a temperature range from ambient to 190 0 C. The maximum error was 2 0 C and was essentially independent of the length or position of the hot zone

  12. Research and development of distributed optic fiber sensors based on Brillouin scattering%布里渊散射的分布式光纤温度传感器的研究进展

    Institute of Scientific and Technical Information of China (English)

    胡佳惠; 张大伟; 陶春先; 黄元申; 倪争技; 庄松林

    2011-01-01

    提要:基于布里渊散射的分布式光纤温度传感技术凭借着其独特的优点,在国内外引起了广泛的关注,成为了一大热点研究,本文综述了基于布里渊散射的分布式光纤温度传感技术的研究现状。在简单介绍了布里渊测温原理的基础上,针对目前布里渊散射的光纤温度传感器存在的在测量范围以及空间分辨率上的缺陷、不足,重点介绍了布里渊散射的分布式光纤温度传感器在一些方法上对测量范围以及空间分辨率上的改进。并对日后布里渊的分布式光纤温度传感器的发展趋势做了展望。%The distributed optic fiber sensors based on Brillouin scattering attracts widely attention because of its unique strengths.The improvement of distributed optic fiber sensors based on Brillouin scattering was reviewed in several field such as spatial resolution,measuring range.After introducing the measurement principles of this technique,some research of the recent situation and finally some predictions of its future development were also presented.

  13. Engineering modes in optical fibers with metamaterial

    DEFF Research Database (Denmark)

    Yan, Min; Mortensen, Asger; Qiu, Min

    2009-01-01

    In this paper, we report a preliminary theoretical study on optical fibers with fine material inclusions whose geometrical inhomogeneity is almost indistinguishable by the operating wavelength.We refer to such fibers as metamaterial optical fibers, which can conceptually be considered...... as an extension from the previously much publicized microstructured optical fibers. Metamaterials can have optical properties not obtainable in naturally existing materials, including artificial anisotropy as well as graded material properties. Therefore, incorporation of metamaterial in optical fiber designs can...

  14. Two Fiber Optical Fiber Thermometry

    Science.gov (United States)

    Jones, Mathew R.; Farmer, Jeffery T.; Breeding, Shawn P.

    2000-01-01

    An optical fiber thermometer consists of an optical fiber whose sensing tip is given a metallic coating. The sensing tip of the fiber is essentially an isothermal cavity, so the emission from this cavity will be approximately equal to the emission from a blackbody. Temperature readings are obtained by measuring the spectral radiative heat flux at the end of the fiber at two wavelengths. The ratio of these measurements and Planck's Law are used to infer the temperature at the sensing tip. Optical fiber thermometers have high accuracy, excellent long-term stability and are immune to electromagnetic interference. In addition, they can be operated for extended periods without requiring re-calibration. For these reasons. it is desirable to use optical fiber thermometers in environments such as the International Space Station. However, it has recently been shown that temperature readings are corrupted by emission from the fiber when extended portions of the probe are exposed to elevated temperatures. This paper will describe several ways in which the reading from a second fiber can be used to correct the corrupted temperature measurements. The accuracy and sensitivity to measurement uncertainty will be presented for each method.

  15. Optical fiber smart sensor for conformity analysis of Brazilian gasoline; Sensor inteligente a fibra otica para analise da conformidade da gosolina brasileira

    Energy Technology Data Exchange (ETDEWEB)

    Possetti, Gustavo R.C.; Camilotti, Emmanuelle; Arruda, Lucia V.R. de; Muller, Marcia; Fabris, Jose L. [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Cocco, Lilian C.; Yamamoto, Carlos I. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil); Falate, Rosane [Universidade Estadual de Ponta Grossa (UEPG), PR (Brazil)

    2008-07-01

    The conventional techniques employed to monitor the gasoline quality are expensive, time-consuming and demands on specialized workers to its execution. A study about the applicability of a long period grating, a fiber optic device, as an auxiliary tool for the analysis of Brazilian gasoline conformity is presented in this work. The long period grating spectral response was measured with the device immersed in samples of gasoline A with different proportions of hydrated ethyl alcohol fuel. A resolution of 0.23 % was obtained for the concentrations range of commercial interest, between 20 % and 40 %. The device performance was also tested with a set of conform and non-conform gasoline C samples. The device spectral response for these samples, as well as the samples densities and the conformity status were employed to train and to validate an artificial neural network with radial base function. The obtained results show that fiber optic sensors supervised by artificial neural networks can constitute systems for smart measurement with high applicability in the analyses of gasoline conformity, reducing costs and time related to conventional tests. (author)

  16. Optical fibers and their applications for radiation measurements

    International Nuclear Information System (INIS)

    Kakuta, Tsunemi

    1998-01-01

    When optical fibers are used in a strong radiation field, it is necessary to increase the radiation-resistant capacity. Aiming at the improvement of such property, the characteristics of recent optical fibers made from quartz-glass were reviewed and the newly developed techniques for radiation measurement using those fibers were summarized in this report. Since optical fibers became able to use in the levels near the core conditions, their applications have started in various fields of technologies related to radiation. By combining the optical fibers and a small sensor, it became possible to act as 'Key Component' for measuring wide range radioactivity from a trace activity to a strong radiation field in the reactor core. Presently, the fibers are utilized for investigation of the optical mechanisms related in radiation, evaluation of their validities so on. Further, the optical fibers are expected to utilize in a multi-parametric measuring system which allows to concomitantly determine the radiation, temperature, pressure, flow amount etc. as an incore monitor. (M.N.)

  17. Optical fibers and their applications for radiation measurements

    Energy Technology Data Exchange (ETDEWEB)

    Kakuta, Tsunemi [Japan Atomic Energy Research Inst., Tokyo (Japan)

    1998-07-01

    When optical fibers are used in a strong radiation field, it is necessary to increase the radiation-resistant capacity. Aiming at the improvement of such property, the characteristics of recent optical fibers made from quartz-glass were reviewed and the newly developed techniques for radiation measurement using those fibers were summarized in this report. Since optical fibers became able to use in the levels near the core conditions, their applications have started in various fields of technologies related to radiation. By combining the optical fibers and a small sensor, it became possible to act as `Key Component` for measuring wide range radioactivity from a trace activity to a strong radiation field in the reactor core. Presently, the fibers are utilized for investigation of the optical mechanisms related in radiation, evaluation of their validities so on. Further, the optical fibers are expected to utilize in a multi-parametric measuring system which allows to concomitantly determine the radiation, temperature, pressure, flow amount etc. as an incore monitor. (M.N.)

  18. Cladding modes of optical fibers: properties and applications

    International Nuclear Information System (INIS)

    Ivanov, Oleg V; Nikitov, Sergei A; Gulyaev, Yurii V

    2006-01-01

    One of the new methods of fiber optics uses cladding modes for controlling propagation of radiation in optical fibers. This paper reviews the results of studies on the propagation, excitation, and interaction of cladding modes in optical fibers. The resonance between core and cladding modes excited by means of fiber Bragg gratings, including tilted ones, is analyzed. Propagation of cladding modes in microstructured fibers is considered. The most frequently used method of exciting cladding modes is described, based on the application of long-period fiber gratings. Examples are presented of long-period gratings used as sensors and gain equalizers for fiber amplifiers, as well as devices for coupling light into and out of optical fibers. (instruments and methods of investigation)

  19. Thin metal bilayer for surface plasmon resonance sensors in a multimode plastic optical fiber: the case of palladium and gold metal films

    Science.gov (United States)

    Cennamo, Nunzio; Zuppella, Paola; Bacco, Davide; Corso, Alain J.; Pelizzo, Maria G.; Pesavento, Maria; Zeni, Luigi

    2016-05-01

    A novel sensing platform based on thin metal bilayer for surface plasmon resonance (SPR) in a D-shaped plastic optical fiber (POF) has been designed, implemented and tested. The experimental results are congruent with the numerical studies. This platform has been properly optimized to work in the 1.38 -1.42 refractive index range and it exhibits excellent sensitivity. This refractive index range is very interesting for bio-chemical applications, where the polymer layer are used as receptors (e.g. molecularly imprinted polymer) or to immobilize the bio-receptor on the metal surface. The proposed metallic bilayer is based on palladium and gold films and replaces the traditional gold by exhibiting higher performances. Furthermore, the deposition of the thin bilayer is a single process and no further manufacturing step is required. In fact, in this case the photoresist buffer layer between the POF core and the metal layer, usually required to increase the refractive index range, is no longer necessary.

  20. Two-way time transfer via optical fiber providing subpicosecond precision and high temperature stability

    Czech Academy of Sciences Publication Activity Database

    Kodet, J.; Pánek, Petr; Procházka, I.

    2015-01-01

    Roč. 53, č. 1 (2015), s. 18-26 ISSN 0026-1394 Institutional support: RVO:67985882 Keywords : optical fiber * time transfer * TWOTT Subject RIV: JB - Sensors, Measurment, Regulation Impact factor: 2.500, year: 2015

  1. Optical fiber meta-tips

    Science.gov (United States)

    Principe, Maria; Micco, Alberto; Crescitelli, Alessio; Castaldi, Giuseppe; Consales, Marco; Esposito, Emanuela; La Ferrara, Vera; Galdi, Vincenzo; Cusano, Andrea

    2016-04-01

    We report on the first example of a "meta-tip" configuration that integrates a metasurface on the tip of an optical fiber. Our proposed design is based on an inverted-Babinet plasmonic metasurface obtained by patterning (via focused ion beam) a thin gold film deposited on the tip of an optical fiber, so as to realize an array of rectangular aperture nanoantennas with spatially modulated sizes. By properly tuning the resonances of the aperture nanoantennas, abrupt variations can be impressed in the field wavefront and polarization. We fabricated and characterized several proof-of-principle prototypes operating an near-infrared wavelengths, and implementing the beam-steering (with various angles) of the cross-polarized component, as well as the excitation of surface waves. Our results pave the way to the integration of the exceptional field-manipulation capabilities enabled by metasurfaces with the versatility and ubiquity of fiber-optics technological platforms.

  2. System for testing optical fibers

    Science.gov (United States)

    Golob, John E. [Olathe, KS; Looney, Larry D. [Los Alamos, NM; Lyons, Peter B. [Los Alamos, NM; Nelson, Melvin A. [Santa Barbara, CA; Davies, Terence J. [Santa Barbara, CA

    1980-07-15

    A system for measuring a combination of optical transmission properties of fiber optic waveguides. A polarized light pulse probe is injected into one end of the optical fiber. Reflections from discontinuities within the fiber are unpolarized whereas reflections of the probe pulse incident to its injection remain polarized. The polarized reflections are prevented from reaching a light detector whereas reflections from the discontinuities reaches the detector.

  3. Lab-on-fiber electrophoretic trace mixture separating and detecting an optofluidic device based on a microstructured optical fiber.

    Science.gov (United States)

    Yang, Xinghua; Guo, Xiaohui; Li, Song; Kong, Depeng; Liu, Zhihai; Yang, Jun; Yuan, Libo

    2016-04-15

    We report an in-fiber integrated electrophoretic trace mixture separating and detecting an optofluidic optical fiber sensor based on a specially designed optical fiber. In this design, rapid in situ separation and simultaneous detection of mixed analytes can be realized under electro-osmotic flow in the microstructured optical fiber. To visually display the in-fiber separating and detecting process, two common fluorescent indicators are adopted as the optofluidic analytes in the optical fiber. Results show that a trace amount of the mixture (0.15 μL) can be completely separated within 3.5 min under a high voltage of 5 kV. Simultaneously, the distributed information of the separated analytes in the optical fiber can be clearly obtained by scanning along the optical fiber using a 355 nm laser. The emission from the analytes can be efficiently coupled into the inner core and guides to the remote end of the optical fiber. In addition, the thin cladding around the inner core in the optical fiber can prevent the fluorescent cross talk between the analytes in this design. Compared to previous optical fiber optofluidic devices, this device first realizes simultaneously separating treatment and the detection of the mixed samples in an optical fiber. Significantly, such an in-fiber integrated separating and detecting optofluidic device can find wide applications in various analysis fields involves mixed samples, such as biology, chemistry, and environment.

  4. Soliton robustness in optical fibers

    International Nuclear Information System (INIS)

    Menyuk, C.R.

    1993-01-01

    Simulations and experiments indicate that solitons in optical fibers are robust in the presence of Hamiltonian deformations such as higher-order dispersion and birefringence but are destroyed in the presence of non-Hamiltonian deformations such as attenuation and the Raman effect. Two hypotheses are introduced that generalize these observations and give a recipe for when deformations will be Hamiltonian. Concepts from nonlinear dynamics are used to make these two hypotheses plausible. Soliton stabilization with frequency filtering is also briefly discussed from this point of view

  5. Non-enzymatic glucose detection based on phenylboronic acid modified optical fibers

    Science.gov (United States)

    Sun, Xiaolan; Li, Nana; Zhou, Bin; Zhao, Wei; Liu, Liyuan; Huang, Chao; Ma, Longfei; Kost, Alan R.

    2018-06-01

    A non-enzymatic, sensitive glucose sensor was fabricated based on an evanescent wave absorbing optical fiber probe. The optical fiber sensor was functionalized by fixing a poly (phenylboronic acid) (polyPBA) film onto the conical region of the single mode fiber. The reflected light intensity of the polyPBA-functionalized fiber sensor increased proportionally with glucose concentration in the range of 0-60 mM, and the sensor showed good reproducibility and stability. The developed sensor possessed a high sensitivity of 0.1787%/mM and good linearity. The measurement of glucose concentration in human serum was also demonstrated.

  6. Nanostructured sapphire optical fiber for sensing in harsh environments

    Science.gov (United States)

    Chen, Hui; Liu, Kai; Ma, Yiwei; Tian, Fei; Du, Henry

    2017-05-01

    We describe an innovative and scalable strategy of transforming a commercial unclad sapphire optical fiber to an allalumina nanostructured sapphire optical fiber (NSOF) that overcomes decades-long challenges faced in the field of sapphire fiber optics. The strategy entails fiber coating with metal Al followed by subsequent anodization to form anodized alumina oxide (AAO) cladding of highly organized pore channel structure. We show that Ag nanoparticles entrapped in AAO show excellent structural and morphological stability and less susceptibility to oxidation for potential high-temperature surface-enhanced Raman Scattering (SERS). We reveal, with aid of numerical simulations, that the AAO cladding greatly increases the evanescent-field overlap both in power and extent and that lower porosity of AAO results in higher evanescent-field overlap. This work has opened the door to new sapphire fiber-based sensor design and sensor architecture.

  7. Optic Fiber Sensing IOT Technology and Application Research

    Directory of Open Access Journals (Sweden)

    Wenjuan Zeng

    2014-10-01

    Full Text Available The growth of the Internet of Things (IOT industry has become a new mark of the communication domain. As the development of the technology of the IOT and the fiber-optical sensor, the combination of the both is a big question to be discussed, and the fiber-optical IOT also has a good development prospect. This article first introduces IOT’s current status, the key technology, the theoretical frame and the applications. Then, it discusses the classification of the optical fiber sensor as well as the development and its application’s situation. Lastly, it puts the optical fiber sensing technology into the IOT, and introduces a specific application which is used in the mine safety based on the fiber-optical IOT.

  8. Multicore optical fiber grating array fabrication for medical sensing applications

    Science.gov (United States)

    Westbrook, Paul S.; Feder, K. S.; Kremp, T.; Taunay, T. F.; Monberg, E.; Puc, G.; Ortiz, R.

    2015-03-01

    In this work we report on a fiber grating fabrication platform suitable for parallel fabrication of Bragg grating arrays over arbitrary lengths of multicore optical fiber. Our system exploits UV transparent coatings and has precision fiber translation that allows for quasi-continuous grating fabrication. Our system is capable of both uniform and chirped fiber grating array spectra that can meet the demands of medical sensors including high speed, accuracy, robustness and small form factor.

  9. Chemical tapering of polymer optical fiber

    Science.gov (United States)

    Rashid, Affa Rozana Abdul; Afiqah Nasution, Amna; Hanim Suranin, Aisyah; Athirah Taib, Nur; Maisarah Mukhtar, Wan; Dasuki, Karsono Ahmad; Annuar Ehsan, Abang

    2017-11-01

    Polymer optical fibers (POFs) have significant advantages over numerous sensing applications. The key element in developing sensor is by removing the cladding of the fiber. The use of organic solvent is one of the methods to create tapered POF in order to expose the core region. In this study, the etching chemicals involved is acetone, methyl isobutyl ketone (MIBK), and acetone-methanol mixture. The POF is immersed in 100%, 80%, and 50% of acetone and MIBK dilution. In addition, the mixture of acetone and methanol is also used for POF etching by the ratio 2:1 of the volume. Acetone has shown to be the most reactive solvent towards POF due to its fastest etching rate compared to MIBK and acetone-methanol mixture. The POF is immersed and lifted from the solution for a specific time, depending on the power loss properties for the purpose of producing unclad POF. In comparison to silica fiber optic, the advantages of POF in terms of its simple technique and easy handling enable it to produce unclad POF without damaging the core region. The surface roughness of the POF is investigated under the microscope after being immersed into different solvent. This method of chemical tapering of POF can be used as the fundamental technique for sensor development. Next, the unclad fiber is immersed into ethanol solutions in order to determine the reaction of unclad POF towards its surrounding. The findings show that this particular sensor is sensitive towards concentration changes ranging between 10 wt% to 50 wt%.

  10. An accurate, flexible and small optical fiber sensor: a novel technological breakthrough for real-time analysis of dynamic blood flow data in vivo.

    Directory of Open Access Journals (Sweden)

    Qiao-ying Yuan

    Full Text Available Because of the limitations of existing methods and techniques for directly obtaining real-time blood data, no accurate microflow in vivo real-time analysis method exists. To establish a novel technical platform for real-time in vivo detection and to analyze average blood pressure and other blood flow parameters, a small, accurate, flexible, and nontoxic Fabry-Perot fiber sensor was designed. The carotid sheath was implanted through intubation of the rabbit carotid artery (n = 8, and the blood pressure and other detection data were determined directly through the veins. The fiber detection results were compared with test results obtained using color Doppler ultrasound and a physiological pressure sensor recorder. Pairwise comparisons among the blood pressure results obtained using the three methods indicated that real-time blood pressure information obtained through the fiber sensor technique exhibited better correlation than the data obtained with the other techniques. The highest correlation (correlation coefficient of 0.86 was obtained between the fiber sensor and pressure sensor. The blood pressure values were positively related to the total cholesterol level, low-density lipoprotein level, number of red blood cells, and hemoglobin level, with correlation coefficients of 0.033, 0.129, 0.358, and 0.373, respectively. The blood pressure values had no obvious relationship with the number of white blood cells and high-density lipoprotein and had a negative relationship with triglyceride levels, with a correlation coefficient of -0.031. The average ambulatory blood pressure measured by the fiber sensor exhibited a negative correlation with the quantity of blood platelets (correlation coefficient of -0.839, P<0.05. The novel fiber sensor can thus obtain in vivo blood pressure data accurately, stably, and in real time; the sensor can also determine the content and status of the blood flow to some extent. Therefore, the fiber sensor can obtain

  11. Detection of volatile organic compounds using an optical fiber sensor coated with a sol-gel silica layer containing immobilized Nile red

    Science.gov (United States)

    Liu, Dejun; Lian, Xiaokang; Mallik, Arun Kumar; Han, Wei; Wei, Fangfang; Yuan, Jinhui; Yu, Chongxiu; Farrell, Gerald; Semenova, Yuliya; Wu, Qiang

    2017-04-01

    A simple volatile organic compound (VOC) sensor based on a tapered small core singlemode fiber (SCSMF) structure is reported. The tapered SCSMF fiber structure with a waist diameter of 7.0 μm is fabricated using a customized microheater brushing technique. Silica based material containing immobilized Nile red was prepared by a sol-gel method and was used as a coating applied to the surface of the tapered fiber structure. Different coating thicknesses created by a 2-pass and 4-pass coating process are investigated. The experiments demonstrate that both sensors show a linear response at different gas concentrations to all three tested VOCs (methanol, ethanol and acetone). The sensor with a thicker coating shows better sensitivities but longer response and recovery times. The best measurement resolutions for the 4-pass coating sensor are estimated to be 2.3 ppm, 1.5 ppm and 3.1 ppm for methanol, ethanol and acetone, respectively. The fastest response and recovery time of 1 min and 5 min are demonstrated by the sensor in the case of methanol.

  12. Applicability study of optical fiber distribution sensing to nuclear facilities

    International Nuclear Information System (INIS)

    Takada, Eiji; Kimura, Atsushi; Nakazawa, Masaharu; Kakuta, Tsunemi

    1999-01-01

    Optical fibers have advantages like flexible configuration, intrinsic immunity for electromagnetic fields etc., and they have been used for signal transmission and as optical fiber sensors (OFSs). By some of these sensor techniques, continuous or discrete distribution of physical parameters can be measured. Here, in order to discuss the applicability of these OFSs to nuclear facilities, irradiation experiments to optical fibers were carried out using the fast neutron source reactor 'YAYOI' and a 60 Co γ source. It has been shown that, under irradiation with fast neutrons, the radiation induced loss increase almost linearly with the neutron fluence. On the other hand, when irradiated with 60 Co γ rays, the loss shows a saturation tendency. As an example of the OFSs, applicability of the Raman distributed temperature sensor (RDTS) to the monitoring of nuclear facilities has been examined. Two correction techniques for radiation induced errors have been developed and for the demonstration of their feasibility, measurements were carried out along the primary piping system of the experimental fast reactor: JOYO. During the continuous measurements with the total dose of more than 10 7 [R], the radiation induced errors showed a saturating tendency and the feasibility of the loss correction technique was demonstrated. Although the time response of the system should be improved, the RDTS can be expected as a noble temperature monitor in nuclear facilities. (author)

  13. Optical Fiber Thermometer Based on Fiber Bragg Gratings

    Science.gov (United States)

    Rosli, Ekbal Bin; Mohd. Noor, Uzer

    2018-03-01

    Fiber Bragg grating has generated much interest in use as sensors to measure strain, temperature, and other physical parameters. It also the most common component used to develop this sensor with the advantages of simple, intrinsic sensing elements, electrically passive operation, EMI immunity, high sensitivity, compact size and potentially low cost [6]. This paper reports the design of an optical fiber thermometer based on fiber Bragg gratings. The system was developed for detecting temperature and strain by monitoring the shift of Bragg wavelength. The shifting of Bragg wavelength is used to indicate the temperature and strain due to the change in the surrounding temperature and strain. When the temperature and strain reach the exact wavelength level of the system, the temperature and strain value will display on the Arduino liquid crystal display (LCD). The optical fiber will provide the broadband light source and after passing the FBG the Bragg wavelength into the optical spectrum analyzer (OSA). The system is based on FBG as a physical quantity sensor. The temperatures measured is taken from the water bath and that of the strain is provided by amount of slotted mass used. The outcome of this project is to characterize the Bragg wavelength shifting from the fiber Bragg grating output. As the conclusion, this project provides an efficient optical fiber thermometer in measuring temperature and strain in order to replace the use of conventional electrical instruments.

  14. 355-nm hypersensitization of optical fibers

    NARCIS (Netherlands)

    Canagasabey, A.; Canning, J.; Groothoff, N.

    2003-01-01

    A study is presented on 355-nm hypersensitization of optical fibers. It is found that the intrinsic 244-nm photosensitivity of boron-codoped germanosilicate optical fibers is enhanced by 355-nm hypersensitization. Hypersensitization through standard polymer coating is also demonstrated.

  15. A novel thermoset polymer optical fiber

    NARCIS (Netherlands)

    Flipsen, T.A C; Steendam, R; Pennings, A.J; Hadziioannou, G

    Polymer optical fibers are being investigated with a view to overcoming some of the disadvantages of glass optical fibers in communications applications. Dense cross-linked polymers, such as the polyisocyanurate discussed here (see figure), have been found to be superior in some respects to the

  16. Eliminating Crystals in Non-Oxide Optical Fiber Preforms and Optical Fibers

    Science.gov (United States)

    Tucker, Dennis S.; LaPointe, Michael R.

    2012-01-01

    Non ]oxide fiber optics such as heavy metal fluoride and chalcogenide glasses are extensively used in infrared transmitting applications such as communication systems, chemical sensors, and laser fiber guides for cutting, welding and medical surgery. The addition of rare earths such as erbium, enable these materials to be used as fiber laser and amplifiers. Some of these glasses however are very susceptible to crystallization. Even small crystals can lead to light scatter and a high attenuation coefficient, limiting their usefulness. Previously two research teams found that microgravity suppressed crystallization in heavy metal fluoride glasses. Looking for a less expensive method to suppress crystallization, ground based research was performed utilizing an axial magnetic field. The experiments revealed identical results to those obtained via microgravity processing. This research then led to a patented process for eliminating crystals in optical fiber preforms and the resulting optical fibers. In this paper, the microgravity results will be reviewed as well as patents and papers relating to the use of magnetic fields in various material and glass processing applications. Finally our patent to eliminate crystals in non ]oxide glasses utilizing a magnetic field will be detailed.

  17. Crack Propagation Calculations for Optical Fibers under Static Bending and Tensile Loads Using Continuum Damage Mechanics

    Science.gov (United States)

    Chen, Yunxia; Cui, Yuxuan; Gong, Wenjun

    2017-01-01

    Static fatigue behavior is the main failure mode of optical fibers applied in sensors. In this paper, a computational framework based on continuum damage mechanics (CDM) is presented to calculate the crack propagation process and failure time of optical fibers subjected to static bending and tensile loads. For this purpose, the static fatigue crack propagation in the glass core of the optical fiber is studied. Combining a finite element method (FEM), we use the continuum damage mechanics for the glass core to calculate the crack propagation path and corresponding failure time. In addition, three factors including bending radius, tensile force and optical fiber diameter are investigated to find their impacts on the crack propagation process and failure time of the optical fiber under concerned situations. Finally, experiments are conducted and the results verify the correctness of the simulation calculation. It is believed that the proposed method could give a straightforward description of the crack propagation path in the inner glass core. Additionally, the predicted crack propagation time of the optical fiber with different factors can provide effective suggestions for improving the long-term usage of optical fibers. PMID:29140284

  18. Radiation damage in optical fibers

    International Nuclear Information System (INIS)

    Lyons, P.B.; Looney, L.D.; Ogle, J.W.

    1983-01-01

    Optical fibers provide important advantages over coaxial cables for many data transmission applications. Some of these applications require that the fibers transmit data during a radiation pulse. Other applications utilize the fiber as a radiation-to-light transducer. In either case, radiation-induced luminescence and absorption must be understood. Most studies of radiation effects in fibers have emphasized time scales of interest in telecommunication systems, from the msec to hour range. Few studies have concentrated on response at times below 1 + s. At Los Alamos, both laboratory electron accelerators and nuclear tests have been used as radiation sources to probe this early time region. The use of a fiber (or any optical medium) as a Cerenkov radiation-to-light transducer is discussed. Since the radiation induces attenuation in the medium, the light output is not proportional to the radiation input. The nonlinearity introduced by this attenuation is calculated

  19. All-optical fiber compressor

    International Nuclear Information System (INIS)

    Ivanov, Luben M.

    2015-01-01

    A simple all-optical fiber compressor, based on an idea of dispersion management using a fiber of positive dispersion in the first part and of negative dispersion in the second one at the working wavelength, is investigated. The method allows a combination of the advantages of the classic fiber-grating and of the multisoliton compression. It is possible to improve substantially the quality of the compressed pulse compared to the multisoliton compression. The compression factor could be increased up to 2-2.5 times when the fraction of the input pulse energy appearing within the compressed pulse enhances more than 2 times. Thus, the peak power of the compressed pulse is able to increase about 5 times and the quality of the obtained pulses should be comparable with those obtained by the fiber-grating compressor

  20. Optical fiber laser sensor with a cavity of 8.6 Km formed by two fiber Bragg gratings used as mirrors

    Energy Technology Data Exchange (ETDEWEB)

    May A, M.; Kuzin, E.A.; Vazquez S, R.A. [Instituto Nacional de Astrofisica, Optica y Electronica, A. P. 51 y 216, C.P. 72000 Puebla (Mexico); Basurto P, M.A. [Universidad Autonoma del Estado de Morelos, Av. Universidad No. 1001, Col. Chamilpa, C.P. 62210 Cuernavaca, Morelos (Mexico); Shlyagin, M.G.; Marquez B, I. [Centro de Investigacion Cientifica y de Ensenanza Superior de Ensenada, C.P. 22860 Ensenada, Baja California (Mexico)

    2002-07-01

    We report the operation of a fiber laser sensor made by an Erbium Doped Fiber pumped at 980 nm, an 8.67 km passive fiber and two fiber Bragg gratings placed at the ends of the laser cavity. Under normal conditions, the Bragg gratings have different reflection wavelengths and laser emission is not generated. The two Bragg gratings can be placed at the same reflection wavelength when the Bragg grating with the lowest reflective wavelength is strained which can be used as a sensor element. The laser generation thus shows that the Bragg grating is under strain. Furthermore, our configuration give us the possibility for knowing the distance between two Bragg gratings when the laser beating frequency is measured. A measurement precision better than 25 m in 8.67 Km is shown to be feasible. (Author)

  1. Optical fiber laser sensor with a cavity of 8.6 Km formed by two fiber Bragg gratings used as mirrors

    CERN Document Server

    May, M; Vázquez, R A; Basurto, M A; Shlyagin, M G; Márquez, I

    2002-01-01

    We report the operation of a fiber laser sensor made by an Erbium Doped Fiber pumped at 980 nm, an 8.67 km passive fiber and two fiber Bragg gratings placed at the ends of the laser cavity. Under normal conditions, the Bragg gratings have different reflection wavelengths and laser emission is not generated. The two Bragg gratings can be placed at the same reflection wavelength when the Bragg grating with the lowest reflective wavelength is strained which can be used as a sensor element. The laser generation thus shows that the Bragg grating is under strain. Furthermore, our configuration give us the possibility for knowing the distance between two Bragg gratings when the laser beating frequency is measured. A measurement precision better than 25 m in 8.67 Km is shown to be feasible. (Author)

  2. Application technology for optical fiber in nuclear facilities

    International Nuclear Information System (INIS)

    Lee, Jong Min; Lee, Yong Bum; Kim, Woong Ki; Kim, Seung Ho; Kim, Chang Hoi; Hwang, Suk Yeong; Kim, Byung Soo; Sohn, Surg Won

    1990-01-01

    The objective of this project is to study the radiation effects on optical fiber, to develop remote inspection and image processing system, and to apply image processing technique to X-ray radiography analysis and to laser beam diagnostic system. Thermal neutrons cause nuclear radiation with fiber compositions, so secondary ionizing radiations of high energy are generated. These ionizing radiations from color centers, which increase transmission loss of optical fiber by absorbing propagating light in fiber core. As a result of experiment, owing to Ge, P, and B doping effects the induced loss in multimode fibers has been 5 times larger than that in single mode fibers, the loss at 0.85 μm wavelength region more susceptible for radiations has been twice higher than that at 1.3 μm. Remote inspection mechanism captures images remotely, and the images are inhanced by image processing surfaces of bent or long-straight pipe in hostile environment. Laser beam diagnostic system using image processing techniques can be used to observe and analyze laser beam quality. This system will be effectively applied for laser development and application field. X-ray radiographic image analysis by image processing technique make it easier to inspect and measure irradiated fuel rod, and the accuracy of the obtained data is also improved. (author)

  3. Crystal-free Formation of Non-Oxide Optical Fiber

    Science.gov (United States)

    Nabors, Sammy A.

    2015-01-01

    Researchers at NASA Marshall Space Flight Center have devised a method for the creation of crystal-free nonoxide optical fiber preforms. Non-oxide fiber optics are extensively used in infrared transmitting applications such as communication systems, chemical sensors, and laser fiber guides for cutting, welding and medical surgery. However, some of these glasses are very susceptible to crystallization. Even small crystals can lead to light scatter and a high attenuation coefficient, limiting their usefulness. NASA has developed a new method of non-oxide fiber formation that uses axial magnetic fields to suppress crystallization. The resulting non-oxide fibers are crystal free and have lower signal attenuation rates than silica based optical fibers.

  4. Essentials of modern optical fiber communication

    CERN Document Server

    Noé, Reinhold

    2016-01-01

    This is a concise introduction into optical fiber communication. It covers important aspects from the physics of optical wave propagation and amplification to the essentials of modulation formats and receivers. The combination of a solid coverage of necessary fundamental theory with an in-depth discussion of recent relevant research results enables the reader to design modern optical fiber communication systems. The book serves both graduate students and professionals. It includes many worked examples with solutions for lecturers. For the second edition, Reinhold Noé made many changes and additions throughout the text so that this concise book presents the essentials of optical fiber communication in an easy readable and understandable way.

  5. Optical fibers and RF a natural combination

    CERN Document Server

    Romeiser, Malcolm

    2004-01-01

    The optical fiber industry has experienced a period of consolidation and reorganization and is now poised for a new surge in growth. To take advantage of that growth, and to respond to the demand to use fiber more efficiently, designers need a better understanding of fiber optics. Taking the approach that optical fibers are an extension of RF-based communications, the author explains basic optical concepts, applications, and systems; the nature and performance characteristics of optical fibers; and optical sources, connectors and splices. Subsequent chapters explore current applications of fib

  6. The influence of concentration of Nd-Fe-B powder in composite coating of optical fiber to the sensibility to external magnetic field

    Directory of Open Access Journals (Sweden)

    Radojević Vesna J.

    2005-01-01

    Full Text Available Multi-mode optical fiber with magnetic composite coating was investigated as an optical fiber sensor element (OFMSE for magnetic field sensing The composite coating was formed with dispersions of permanent magnet powder of Nd-Fe-B in poly (ethylene-co-vinyl acetate-EVA solutions in toluene. The influence of the applied external magnetic field on the change of intensity of the light signal propagate trough developed optical fibers sensor element was investigated. In this paper the influence of the content of magnetic powder in the composite coating on the optical propagation characteristics of optical fiber were particularly investigated.

  7. Plastic Optical Fiber Sensing of Alcohol Concentration in Liquors

    Directory of Open Access Journals (Sweden)

    Masayuki Morisawa

    2012-01-01

    Full Text Available A simple optical fiber sensing system of alcohol concentration in liquors has been studied. In this sensor head, a mixture polymer of novolac resin and polyvinylidenefluoride (PVDF with a ratio of 9 : 1 was coated as a sensitive cladding layer on the plastic fiber core made of polystyrene-(PS-coated polycarbonate (PC. Using this sensor head and a green LED light source, it was confirmed that alcohol concentration in several kinds of liquors from beer to whisky can easily be measured with a fast response time less than 1 minute.

  8. Plastic Optical Fiber Sensing of Alcohol Concentration in Liquors

    OpenAIRE

    Masayuki Morisawa; Shinzo Muto

    2012-01-01

    A simple optical fiber sensing system of alcohol concentration in liquors has been studied. In this sensor head, a mixture polymer of novolac resin and polyvinylidenefluoride (PVDF) with a ratio of 9 : 1 was coated as a sensitive cladding layer on the plastic fiber core made of polystyrene-(PS-)coated polycarbonate (PC). Using this sensor head and a green LED light source, it was confirmed that alcohol concentration in several kinds of liquors from beer to whisky can easily be measured with a...

  9. Chemical tapering of polymer optical fiber

    Directory of Open Access Journals (Sweden)

    Abdul Rashid Affa Rozana

    2017-01-01

    Full Text Available Polymer optical fibers (POFs have significant advantages over numerous sensing applications. The key element in developing sensor is by removing the cladding of the fiber. The use of organic solvent is one of the methods to create tapered POF in order to expose the core region. In this study, the etching chemicals involved is acetone, methyl isobutyl ketone (MIBK, and acetone-methanol mixture. The POF is immersed in 100%, 80%, and 50% of acetone and MIBK dilution. In addition, the mixture of acetone and methanol is also used for POF etching by the ratio 2:1 of the volume. Acetone has shown to be the most reactive solvent towards POF due to its fastest etching rate compared to MIBK and acetone-methanol mixture. The POF is immersed and lifted from the solution for a specific time, depending on the power loss properties for the purpose of producing unclad POF. In comparison to silica fiber optic, the advantages of POF in terms of its simple technique and easy handling enable it to produce unclad POF without damaging the core region. The surface roughness of the POF is investigated under the microscope after being immersed into different solvent. This method of chemical tapering of POF can be used as the fundamental technique for sensor development. Next, the unclad fiber is immersed into ethanol solutions in order to determine the reaction of unclad POF towards its surrounding. The findings show that this particular sensor is sensitive towards concentration changes ranging between 10 wt% to 50 wt%.

  10. Analysis of seawater flow through optical fiber

    Science.gov (United States)

    Fernández López, Sheila; Carrera Ramírez, Jesús; Rodriguez Sinobar, Leonor; Benitez, Javier; Rossi, Riccardo; Laresse de Tetto, Antonia

    2015-04-01

    The relation between sea and coastal aquifer is very important to the human populations living in coastal areas. The interrelation involves the submarine ground water discharge of relatively fresh water to the sea and the intrusion of sea water into the aquifer, which impairs the quality of ground water. The main process in seawater intrusion is managed by fluid-density effects which control the displacement of saline water. The underlain salinity acts as the restoring force, while hydrodynamic dispersion and convection lead to a mixing and vertical displacement of the brine. Because of this, a good definition of this saltwater-freshwater interface is needed what is intimately joined to the study of the movements (velocity fields) of fresh and salt water. As it is well known, the flow of salt water studied in seawater intrusion in stationary state, is nearly null or very low. However, in the rest of cases, this flux can be very important, so it is necessary its study to a better comprehension of this process. One possible manner of carry out this analysis is through the data from optical fiber. So, to research the distribution and velocity of the fresh and saltwater in the aquifer, a fiber optic system (OF) has been installed in Argentona (Baix Maresme, Catalonia). The main objective is to obtain the distributed temperature measurements (OF-DTS) and made progress in the interpretation of the dynamic processes of water. For some applications, the optical fiber acts as a passive temperature sensor but in our case, the technique Heated Active Fiber Optic will be used. This is based on the thermal response of the ground as a heat emission source is introduced. The thermal properties of the soil, dependent variables of soil water content, will make a specific temperature distribution around the cable. From the analyzed data we will deduce the velocity field, the real objective of our problem. To simulate this phenomenon and the coupled transport and flow problem

  11. High Performance Graded Index Polymer Optical Fibers

    National Research Council Canada - National Science Library

    Garito, Anthony

    1998-01-01

    ...) plastic optical fibers (POF) and graded index (GI) POFs are reported. A set of criteria and analyses of physical parameters are developed in context to the major issues of POF applications in short-distance communication systems...

  12. Supersymmetric Transformations in Optical Fibers

    Science.gov (United States)

    Macho, Andrés; Llorente, Roberto; García-Meca, Carlos

    2018-01-01

    Supersymmetry (SUSY) has recently emerged as a tool to design unique optical structures with degenerate spectra. Here, we study several fundamental aspects and variants of one-dimensional SUSY in axially symmetric optical media, including their basic spectral features and the conditions for degeneracy breaking. Surprisingly, we find that the SUSY degeneracy theorem is partially (totally) violated in optical systems connected by isospectral (broken) SUSY transformations due to a degradation of the paraxial approximation. In addition, we show that isospectral constructions provide a dimension-independent design control over the group delay in SUSY fibers. Moreover, we find that the studied unbroken and isospectral SUSY transformations allow us to generate refractive-index superpartners with an extremely large phase-matching bandwidth spanning the S +C +L optical bands. These singular features define a class of optical fibers with a number of potential applications. To illustrate this, we numerically demonstrate the possibility of building photonic lanterns supporting broadband heterogeneous supermodes with large effective area, a broadband all-fiber true-mode (de)multiplexer requiring no mode conversion, and different mode-filtering, mode-conversion, and pulse-shaping devices. Finally, we discuss the possibility of extrapolating our results to acoustics and quantum mechanics.

  13. Radiation resistance of optical fibers, (10)

    International Nuclear Information System (INIS)

    Tsunoda, Tsunemi; Ara, Katsuyuki; Morimoto, Naoki; Sanada, Kazuo; Inada, Koichi.

    1991-01-01

    Optical fibers have many excellent characteristics such as the light weight of the material, insulation, the noninductivity of electromagnetic interference noise, the wide band of signal transmission, and small loss. Also in the field of atomic energy, the utilization of optical fibers is positively expanded, and the research on the method of application and so on has been advanced. However in optical fibers, there is the problem that color centers are formed at the relatively low level of radiation, and they are colored. Accordingly, for effectively utilizing optical fibers in radiation environment, it is indispensable to improve their radiation resistance. For the purpose of solving this problem, the authors have carried out the basic research on the effect that radiation exerts to optical fibers and the development of the optical fibers having excellent radiation resistance. For the purpose of expanding the range of application of GeO 2 -doped silica core fibers including GI type in radiation regions, the transmission characteristics of the fibers during irradiation were examined by using the Cl content as the parameter. Therefore, the results are reported. The fibers put to the test, the testing method and the results are described. (K.I.)

  14. Cantilever-based optical interfacial force microscope in liquid using an optical-fiber tip

    Directory of Open Access Journals (Sweden)

    Byung I. Kim

    2013-03-01

    Full Text Available We developed a novel cantilever-based optical interfacial force microscope (COIFM to study molecular interaction in liquid environments. The force sensor was created by attaching a chemically etched optical-fiber tip to the force sensor with UV epoxy, and characterized by imaging on a calibration grid. The performance of the COIFM was then demonstrated by measuring the force between two oxidized silicon surfaces in 1 mM KCl as a function of distance. The result was consistent with previously reported electrical double layer forces, suggesting that a COIFM using an optical-fiber tip is capable of measuring force in a liquid environment.

  15. A novel U-bent plastic optical fibre local surface plasmon resonance sensor based on a graphene and silver nanoparticle hybrid structure

    International Nuclear Information System (INIS)

    Jiang, Shouzhen; Li, Zhe; Zhang, Chao; Gao, Saisai; Li, Zhen; Li, Chonghui; Yang, Cheng; Liu, Mei; Qiu, Hengwei; Liu, Yanjun

    2017-01-01

    In this work, we have presented a novel local surface plasmon resonance (LSPR) sensor based on the U-bent plastic optical fibre (U-POF). Firstly, a layer of discontinuous silver (Ag) thin film was deposited on the U-POF and then the Ag film was covered by a layer of cladding synthesized by polyvinyl alcohol (PVA), graphene and silver nanoparticles forming the PVA/G/AgNPs@Ag film. The normalized transmittance spectrum of the LSPR sensor have been collected in a range of the refractive index (RI) from 1.330 to 1.3657 in ethanol solution, and 700.3 nm/RIU sensitivity of the developed LSPR sensor has been demonstrated. By experiments, we demonstrated that the graphene could improve the sensitivity of the LSPR sensor and delay the oxidation process of the AgNPs effectively to keep the stability of the LSPR sensor. The LSPR sensor also exhibited good sensitivity and linearity in the detection of glucose solutions. This work shows that the developed LSPR sensor may have promising applications in biosensing. (paper)

  16. Selective detection of antibodies in microstructured polymer optical fibers

    DEFF Research Database (Denmark)

    Jensen, Jesper Bo Damm; Hoiby, P.E.; Emiliyanov, Grigoriy Andreev

    2005-01-01

    was applied to selectively capture either α-streptavidin or α-CRP antibodies inside these air holes. A sensitive and easy-to-use fluorescence method was used for the optical detection. Our results show that mPOF based biosensors can provide reliable and selective antibody detection in ultra small sample......We demonstrate selective detection of fluorophore labeled antibodies from minute samples probed by a sensor layer of complementary biomolecules immobilized inside the air holes of microstructured Polymer Optical Fiber (mPOF). The fiber core is defined by a ring of 6 air holes and a simple procedure...

  17. Localized biosensing with Topas microstructured Polymer Optical Fiber

    DEFF Research Database (Denmark)

    Emiliyanov, Grigoriy Andreev; Jensen, Jesper Bo; Bang, Ole

    2007-01-01

    We present what is believed to be the first microstructured polymer optical fiber (mPOF) fabricated from Topas cyclic olefin copolymer, which has attractive material and biochemical properties. This polymer allows for a novel type of fiber-optic biosensor, where localized sensor layers may...... be activated on the inner side of the air holes in a predetermined section of the mPOF. The concept is demonstrated using a fluorescencebased method for selective detection of fluorophore-labeled antibodies. © 2007 Optical Society of America...

  18. Optical Fiber Sensing Based on Reflection Laser Spectroscopy

    Directory of Open Access Journals (Sweden)

    Gianluca Gagliardi

    2010-03-01

    Full Text Available An overview on high-resolution and fast interrogation of optical-fiber sensors relying on laser reflection spectroscopy is given. Fiber Bragg-gratings (FBGs and FBG resonators built in fibers of different types are used for strain, temperature and acceleration measurements using heterodyne-detection and optical frequency-locking techniques. Silica fiber-ring cavities are used for chemical sensing based on evanescent-wave spectroscopy. Various arrangements for signal recovery and noise reduction, as an extension of most typical spectroscopic techniques, are illustrated and results on detection performances are presented.

  19. Curved Piezoelectric Actuators for Stretching Optical Fibers

    Science.gov (United States)

    Allison, Sidney G.; Shams, Qamar A.; Fox, Robert L.

    2008-01-01

    Assemblies containing curved piezoceramic fiber composite actuators have been invented as means of stretching optical fibers by amounts that depend on applied drive voltages. Piezoceramic fiber composite actuators are conventionally manufactured as sheets or ribbons that are flat and flexible, but can be made curved to obtain load-carrying ability and displacement greater than those obtainable from the flat versions. In the primary embodiment of this invention, piezoceramic fibers are oriented parallel to the direction of longitudinal displacement of the actuators so that application of drive voltage causes the actuator to flatten, producing maximum motion. Actuator motion can be transmitted to the optical fiber by use of hinges and clamp blocks. In the original application of this invention, the optical fiber contains a Bragg grating and the purpose of the controlled stretching of the fiber is to tune the grating as part of a small, lightweight, mode-hop-free, rapidly tunable laser for demodulating strain in Bragg-grating strain-measurement optical fibers attached to structures. The invention could also be used to apply controllable tensile force or displacement to an object other than an optical fiber.

  20. Evaluation of an optical fiber probe for in vivo measurement of the photoacoustic response of tissues

    Science.gov (United States)

    Beard, Paul C.; Mills, Timothy N.

    1995-05-01

    A miniature (1 mm diameter) all-optical photoacoustic probe for generating and detecting ultrasonic thermoelastic waves in biological media at the tip of an optical fiber has been developed. The probe provides a compact and convenient means of performing pulsed photoacoustic spectroscopy for the characterization of biological tissue. The device is based upon a transparent Fabry Perot polymer film ultrasound sensor mounted directly over the end of a multimode optical fiber. The optical fiber is used to deliver nanosecond laser pulses to the tissue producing thermoelastic waves which are then detected by the sensor. Detection sensitivities of 53 mv/MPa and a 10 kPa acoustic noise floor have been demonstrated giving excellent signal to noise ratios in a strong liquid absorber. Lower, but clearly detectable, signals in post mortem human aorta have also been observed. The performance and small physical size of the device suggest that it has the potential to perform remote in situ photoacoustic measurements in tissue.

  1. Optical fiber applied to radiation detection

    Energy Technology Data Exchange (ETDEWEB)

    Junior, Francisco A.B.; Costa, Antonella L.; Oliveira, Arno H. de; Vasconcelos, Danilo C., E-mail: fanbra@yahoo.com.br, E-mail: antonella@nuclear.ufmg.br, E-mail: heeren@nuclear.ufmg.br, E-mail: danilochagas@yahoo.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Escola de Engenharia. Departamento de Engenharia Nuclear

    2015-07-01

    In the last years, the production of optical fibers cables has make possible the development of a range of spectroscopic probes for in situ analysis performing beyond nondestructive tests, environmental monitoring, security investigation, application in radiotherapy for dose monitoring, verification and validation. In this work, a system using an optical fiber cable to light signal transmission from a NaI(Tl) radiation detector is presented. The innovative device takes advantage mainly of the optical fibers small signal attenuation and immunity to electromagnetic interference to application for radiation detection systems. The main aim was to simplify the detection system making it to reach areas where the conventional device cannot access due to its lack of mobility and external dimensions. Some tests with this innovative system are presented and the results stimulate the continuity of the researches. (author)

  2. Optical fiber cable chemical stripping fixture

    Science.gov (United States)

    Kolasinski, John R. (Inventor); Coleman, Alexander M. (Inventor)

    1995-01-01

    An elongated fixture handle member is connected to a fixture body member with both members having interconnecting longitudinal central axial bores for the passage of an optical cable therethrough. The axial bore of the fixture body member, however, terminates in a shoulder stop for the outer end of a jacket of the optical cable covering both an optical fiber and a coating therefor, with an axial bore of reduced diameter continuing from the shoulder stop forward for a predetermined desired length to the outer end of the fixture body member. A subsequent insertion of the fixture body member including the above optical fiber elements into a chemical stripping solution results in a softening of the exposed external coating thereat which permits easy removal thereof from the optical fiber while leaving a desired length coated fiber intact within the fixture body member.

  3. Optical fiber designs for beam shaping

    Science.gov (United States)

    Farley, Kevin; Conroy, Michael; Wang, Chih-Hao; Abramczyk, Jaroslaw; Campbell, Stuart; Oulundsen, George; Tankala, Kanishka

    2014-03-01

    A large number of power delivery applications for optical fibers require beams with very specific output intensity profiles; in particular applications that require a focused high intensity beam typically image the near field (NF) intensity distribution at the exit surface of an optical fiber. In this work we discuss optical fiber designs that shape the output beam profile to more closely correspond to what is required in many real world industrial applications. Specifically we present results demonstrating the ability to transform Gaussian beams to shapes required for industrial applications and how that relates to system parameters such as beam product parameter (BPP) values. We report on the how different waveguide structures perform in the NF and show results on how to achieve flat-top with circular outputs.

  4. Microstructured optical fibers - Fundamentals and applications

    DEFF Research Database (Denmark)

    Lægsgaard, Jesper; Bjarklev, Anders Overgaard

    2006-01-01

    In recent years optical fibers having a complex microstructure in the transverse plane have attracted much attention from both researchers and industry. Such fibers can either guide light through total internal reflection or the photonic bandgap effect. Among the many unique applications offered...... by these fibers are mode guidance in air, highly flexible dispersion engineering, and the use of very heterogeneous material combinations. In this paper, we review the different types and applications of microstructured optical fibers, with particular emphasis on recent advances in the field....

  5. Optimization and Application of Reflective LSPR Optical Fiber Biosensors Based on Silver Nanoparticles

    Directory of Open Access Journals (Sweden)

    Jiangping Chen

    2015-05-01

    Full Text Available In this study, we developed a reflective localized surface plasmon resonance (LSPR optical fiber sensor, based on silver nanoparticles (Ag NPs. To enhance the sensitivity of the LSPR optical sensor, two key parameters were optimized, the length of the sensing area and the coating time of the Ag NPs. A sensing length of 1.5 cm and a 1-h coating time proved to be suitable conditions to produce highly sensitive sensors for biosensing. The optimized sensor has a high refractive index sensitivity of 387 nm/RIU, which is much higher than that of other reported individual silver nanoparticles in solutions. Moreover, the sensor was further modified with antigen to act as a biosensor. Distinctive wavelength shifts were found after each surface modification step. In addition, the reflective LSPR optical fiber sensor has high reproducibility and stability.

  6. Refractive Index Measurement of Liquids Based on Microstructured Optical Fibers

    Directory of Open Access Journals (Sweden)

    Susana Silva

    2014-12-01

    Full Text Available This review is focused on microstructured optical fiber sensors developed in recent years for liquid RI sensing. The review is divided into three parts: the first section introduces a general view of the most relevant refractometric sensors that have been reported over the last thirty years. Section 2 discusses several microstructured optical fiber designs, namely, suspended-core fiber, photonic crystal fiber, large-core air-clad photonic crystal fiber, and others. This part is also divided into two main groups: the interferometric-based and resonance-based configurations. The sensing methods rely either on full/selective filling of the microstructured fiber air holes with a liquid analyte or by simply immersing the sensing fiber into the liquid analyte. The sensitivities and resolutions are tabled at the end of this section followed by a brief discussion of the obtained results. The last section concludes with some remarks about the microstructured fiber-based configurations developed for RI sensing and their potential for future applications.

  7. Optical Communication over Plastic Optical Fibers Integrated Optical Receiver Technology

    CERN Document Server

    Atef, Mohamed

    2013-01-01

    This book presents high-performance data transmission over plastic optical fibers (POF) using integrated optical receivers having good properties with multilevel modulation, i.e. a higher sensitivity and higher data rate transmission over a longer plastic optical fiber length. Integrated optical receivers and transmitters with high linearity are introduced for multilevel communication. For binary high-data rate transmission over plastic optical fibers, an innovative receiver containing an equalizer is described leading also to a high performance of a plastic optical fiber link. The cheap standard PMMA SI-POF (step-index plastic optical fiber) has the lowest bandwidth and the highest attenuation among multimode fibers. This small bandwidth limits the maximum data rate which can be transmitted through plastic optical fibers. To overcome the problem of the plastic optical fibers high transmission loss, very sensitive receivers must be used to increase the transmitted length over POF. The plastic optical fiber li...

  8. Fire Source Localization Based on Distributed Temperature Sensing by a Dual-Line Optical Fiber System.

    Science.gov (United States)

    Sun, Miao; Tang, Yuquan; Yang, Shuang; Li, Jun; Sigrist, Markus W; Dong, Fengzhong

    2016-06-06

    We propose a method for localizing a fire source using an optical fiber distributed temperature sensor system. A section of two parallel optical fibers employed as the sensing element is installed near the ceiling of a closed room in which the fire source is located. By measuring the temperature of hot air flows, the problem of three-dimensional fire source localization is transformed to two dimensions. The method of the source location is verified with experiments using burning alcohol as fire source, and it is demonstrated that the method represents a robust and reliable technique for localizing a fire source also for long sensing ranges.

  9. Research of hydroelectric generating set low-frequency vibration monitoring system based on optical fiber sensing

    Science.gov (United States)

    Min, Li; Zhang, Xiaolei; Zhang, Faxiang; Sun, Zhihui; Li, ShuJuan; Wang, Meng; Wang, Chang

    2017-10-01

    In order to satisfy hydroelectric generating set low-frequency vibration monitoring, the design of Passive low-frequency vibration monitoring system based on Optical fiber sensing in this paper. The hardware of the system adopts the passive optical fiber grating sensor and unbalanced-Michelson interferometer. The software system is used to programming by Labview software and finishing the control of system. The experiment show that this system has good performance on the standard vibration testing-platform and it meets system requirements. The frequency of the monitoring system can be as low as 0.2Hz and the resolution is 0.01Hz.

  10. Biomedical and sensing applications of a multi-mode biodegradable phosphate-based optical fiber

    Science.gov (United States)

    Podrazky, Ondřej; Peterka, Pavel; Vytykáčová, SoÅa.; Proboštová, Jana; Kuneš, Martin; Lyutakov, Oleksiy; Ceci-Ginistrelli, Edoardo; Pugliese, Diego; Boetti, Nadia G.; Janner, Davide; Milanese, Daniel

    2018-02-01

    We report on the employment of a biodegradable phosphate-based optical fiber as a pH sensing probe in physiological environment. The phosphate-based optical fiber preform was fabricated by the rod-in-tube technique. The fiber biodegradability was first tested in-vitro and then its biodegradability and toxicity were tested in-vivo. Optical probes for pH sensing were prepared by the immobilization of a fluorescent dye on the fiber tip by a sol-gel method. The fluorescence response of the pH-sensor was measured as a ratio of the emission intensities at the excitation wavelengths of 405 and 450 nm.

  11. Electrically Insulated Sensing of Respiratory Rate and Heartbeat Using Optical Fibers

    Directory of Open Access Journals (Sweden)

    Ernesto Suaste-Gómez

    2014-11-01

    Full Text Available Respiratory and heart rates are among the most important physiological parameters used to monitor patients’ health. It is important to design devices that can measure these parameters without risking or altering the subject’s health. In this context, a novel sensing method to monitor simultaneously the heartbeat and respiratory rate signals of patients within an electrically safety environment was developed and tested. An optical fiber-based sensor was used in order to detect two optical phenomena. Photo-plethysmography and the relation between bending radius and attenuation of optical fiber were coupled through a single beam light traveling along this fiber.

  12. Uniformly thinned optical fibers produced via HF etching with spectral and microscopic verification.

    Science.gov (United States)

    Bal, Harpreet K; Brodzeli, Zourab; Dragomir, Nicoleta M; Collins, Stephen F; Sidiroglou, Fotios

    2012-05-01

    A method for producing uniformly thinned (etched) optical fibers is described, which can also be employed to etch optical fibers containing a Bragg grating (FBG) uniformly for evanescent-field-based sensing and other applications. Through a simple modification of this method, the fabrication of phase-shifted FBGs based on uneven etching is also shown. The critical role of how a fiber is secured is shown, and the success of the method is illustrated, by differential interference contrast microscopy images of uniformly etched FBGs. An etched FBG sensor for the monitoring of the refractive index of different glycerin solutions is demonstrated.

  13. Fire Source Localization Based on Distributed Temperature Sensing by a Dual-Line Optical Fiber System

    Directory of Open Access Journals (Sweden)

    Miao Sun

    2016-06-01

    Full Text Available We propose a method for localizing a fire source using an optical fiber distributed temperature sensor system. A section of two parallel optical fibers employed as the sensing element is installed near the ceiling of a closed room in which the fire source is located. By measuring the temperature of hot air flows, the problem of three-dimensional fire source localization is transformed to two dimensions. The method of the source location is verified with experiments using burning alcohol as fire source, and it is demonstrated that the method represents a robust and reliable technique for localizing a fire source also for long sensing ranges.

  14. Behavior of optical fibers under heavy irradiation

    International Nuclear Information System (INIS)

    Kakuta, T.; Sagawa, T.

    1998-01-01

    Several kinds of optical diagnostics are planned in a fusion reactor. Complicated optical systems such as periscopes are thought to be primary candidates for optical measurements, especially for visible wavelengths. However, optical fibers have several advantages over such optical systems. Also, the optical fibers could be a far better transmission line for signals under a high electromagnetic field. However, they have been considered vulnerable to heavy irradiation. In this study, several kinds of optical fibers were irradiated in the JMTR fission reactor. The optical transmissivity in fibers was measured in situ during fast neutron and gamma irradiation, up to doses of 2 x 10 24 n m -2 and 5 x 10 9 Gy, respectively. The irradiation temperature ranged from 300 to 700 K. For pure ionizing irradiation environments, some methods for improving the radiation resistance of optical fibers were indicated. The results showed that effects of the irradiation associated with fast neutrons would be different from the effects of pure ionizing irradiation. Some fibers were found to withstand the heavy irradiation, especially in an infrared wavelength range. (orig.)

  15. Use of optical fibers in spectrophotometry

    Science.gov (United States)

    Ramsey, Lawrence W.

    1988-01-01

    The use of single or small numbers of fiber optic fibers in astronomical spectroscopy with the goal of greater spectrophotometric and radial velocity accuracy is discussed. The properties of multimode step index fibers which are most important for this application are outlined, as are laboratory tests of currently available fibers.

  16. Designing in-building optical fiber networks

    NARCIS (Netherlands)

    Koonen, A.M.J.; Boom, van den H.P.A.; Tangdiongga, E.; Jung, H.D.; Guignard, P.

    2010-01-01

    Optical fiber in-building networks carrying wired and wireless services can outperform CAT-5E networks regarding versatility and installation costs. POF-based point-to-point architectures are optimum for small buildings, and (optically routed) SMF-based bus architectures for larger buildings.

  17. Nonlinear soliton matching between optical fibers

    DEFF Research Database (Denmark)

    Agger, Christian; Sørensen, Simon Toft; Thomsen, Carsten L.

    2011-01-01

    In this Letter, we propose a generic nonlinear coupling coefficient, η2 NL ¼ ηjγ=β2jfiber2=jγ=β2jfiber1, which gives a quantitative measure for the efficiency of nonlinear matching of optical fibers by describing how a fundamental soliton couples from one fiber into another. Specifically, we use η...

  18. Radiation damage in commercial optical fibers

    International Nuclear Information System (INIS)

    Bertolotti, M.; Franceschini, F.A.; Serra, A.

    1978-01-01

    Experimental results obtained by exposure of commercial optical fibers to 60 Co γ-ray irradiation, are reported. The possibility of utilizing these fibers as far as a total dose of 6000 rad in the light spectrum is shown. It is also shown that it is possible to obtain total recovery of irradiated fibers by annealing at 500 0 C. (author)

  19. UV irradiation assisted growth of ZnO nanowires on optical fiber surface

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Bo; Shi, Tielin; Liao, Guanglan; Li, Xiaoping; Huang, Jie; Zhou, Temgyuan; Tang, Zirong, E-mail: zirong@mail.hust.edu.cn

    2017-06-01

    Highlights: • A new fabrication process combined a hydrothermal process with UV irradiation from optical fiber is developed. • The growth of ZnO nanowires is efficient in the utilization of UV light. • A novel hybrid structure which integrates ZnO nanowires on optical fiber surface is synthesized. • The UV assisted growth of ZnO nanowires shows preferred orientation and better quality. • A mechanism of growing ZnO nanowires under UV irradiation is proposed. - Abstract: In this paper, a novel approach was developed for the enhanced growth of ZnO nanowires on optical fiber surface. The method combined a hydrothermal process with the efficient UV irradiation from the fiber core, and the effects of UV irradiation on the growth behavior of ZnO nanowires were investigated. The results show that UV irradiation had great effects on the preferred growth orientation and the quality of the ZnO nanowires. The crystallization velocity along the c-axis would increase rapidly with the increase of the irradiation power, while the growth process in the lateral direction was marginally affected by the irradiation. The structure of ZnO nanowires also shows less oxygen vacancy with UV irradiation of higher power. The developed approach is applicable for the efficient growth of nanowires on the fiber surface, and the ZnO nanowires/optical fiber hybrid structures have great potentials for a wide variety of applications such as optical fiber sensors and probes.

  20. New Methods of Enhancing the Thermal Durability of Silica Optical Fibers

    Directory of Open Access Journals (Sweden)

    Karol Wysokiński

    2014-10-01

    Full Text Available Microstructured optical fibers can be precisely tailored for many different applications, out of which sensing has been found to be particularly interesting. However, placing silica optical fiber sensors in harsh environments results in their quick destruction as a result of the hydrolysis process. In this paper, the degradation mechanism of bare and metal-coated optical fibers at high temperatures under longitudinal strain has been determined by detailed analysis of the thermal behavior of silica and metals, like copper and nickel. We furthermore propose a novel method of enhancing the lifetime of optical fibers by the deposition of electroless nickel-phosphorous alloy in a low-temperature chemical process. The best results were obtained for a coating comprising an inner layer of copper and outer layer of low phosphorous nickel. Lifetime values obtained during the annealing experiments were extrapolated to other temperatures by a dedicated model elaborated by the authors. The estimated copper-coated optical fiber lifetime under cycled longitudinal strain reached 31 h at 450 °C.

  1. New Methods of Enhancing the Thermal Durability of Silica Optical Fibers.

    Science.gov (United States)

    Wysokiński, Karol; Stańczyk, Tomasz; Gibała, Katarzyna; Tenderenda, Tadeusz; Ziołowicz, Anna; Słowikowski, Mateusz; Broczkowska, Małgorzata; Nasiłowski, Tomasz

    2014-10-13

    Microstructured optical fibers can be precisely tailored for many different applications, out of which sensing has been found to be particularly interesting. However, placing silica optical fiber sensors in harsh environments results in their quick destruction as a result of the hydrolysis process. In this paper, the degradation mechanism of bare and metal-coated optical fibers at high temperatures under longitudinal strain has been determined by detailed analysis of the thermal behavior of silica and metals, like copper and nickel. We furthermore propose a novel method of enhancing the lifetime of optical fibers by the deposition of electroless nickel-phosphorous alloy in a low-temperature chemical process. The best results were obtained for a coating comprising an inner layer of copper and outer layer of low phosphorous nickel. Lifetime values obtained during the annealing experiments were extrapolated to other temperatures by a dedicated model elaborated by the authors. The estimated copper-coated optical fiber lifetime under cycled longitudinal strain reached 31 h at 450 °C.

  2. Respiration rate detection based on intensity modulation using plastic optical fiber

    Science.gov (United States)

    Anwar, Zawawi Mohd; Ziran Nurul Sufia, Nor; Hadi, Manap

    2017-11-01

    This paper presents the implementation of respiration rate measurement via a simple intensity-based optical fiber sensor using optical fiber technology. The breathing rate is measured based on the light intensity variation due to the longitudinal gap changes between two separated fibers. In order to monitor the breathing rate continuously, the output from the photodetector conditioning circuit is connected to a low-cost Arduino kit. At the sensing point, two optical fiber cables are positioned in series with a small gap and fitted inside a transparent plastic tube. To ensure smooth movement of the fiber during inhale and exhale processes as well as to maintain the gap of the fiber during idle condition, the fiber is attached firmly to a stretchable bandage. This study shows that this simple fiber arrangement can be applied to detect respiration activity which might be critical for patient monitoring.

  3. Respiration rate detection based on intensity modulation using plastic optical fiber

    Directory of Open Access Journals (Sweden)

    Mohd Anwar Zawawi

    2017-01-01

    Full Text Available This paper presents the implementation of respiration rate measurement via a simple intensity-based optical fiber sensor using optical fiber technology. The breathing rate is measured based on the light intensity variation due to the longitudinal gap changes between two separated fibers. In order to monitor the breathing rate continuously, the output from the photodetector conditioning circuit is connected to a low-cost Arduino kit. At the sensing point, two optical fiber cables are positioned in series with a small gap and fitted inside a transparent plastic tube. To ensure smooth movement of the fiber during inhale and exhale processes as well as to maintain the gap of the fiber during idle condition, the fiber is attached firmly to a stretchable bandage. This study shows that this simple fiber arrangement can be applied to detect respiration activity which might be critical for patient monitoring.

  4. The effect of irradiation process on the optical fiber coating

    Science.gov (United States)

    Wang, Zeyu; Xiao, Chun; Rong, Liang; Ji, Wei

    2018-03-01

    Protective fiber coating decides the mechanical strength of an optical fiber as well as its resistance against the influence of environment, especially in some special areas like irradiation atmospheres. According to the experiment in this paper, it was found that the tensile force and peeling force of resistant radiation optical fiber was improved because of the special optical fiber coating.

  5. Plasmonic Optical Fiber-Grating Immunosensing: A Review.

    Science.gov (United States)

    Guo, Tuan; González-Vila, Álvaro; Loyez, Médéric; Caucheteur, Christophe

    2017-11-26

    Plasmonic immunosensors are usually made of a noble metal (in the form of a film or nanoparticles) on which bioreceptors are grafted to sense analytes based on the antibody/antigen or other affinity mechanism. Optical fiber configurations are a miniaturized counterpart to the bulky Kretschmann prism and allow easy light injection and remote operation. To excite a surface plasmon (SP), the core-guided light is locally outcoupled. Unclad optical fibers were the first configurations reported to this end. Among the different architectures able to bring light in contact with the surrounding medium, a great quantity of research is today being conducted on metal-coated fiber gratings photo-imprinted in the fiber core, as they provide modal features that enable SP generation at any wavelength, especially in the telecommunication window. They are perfectly suited for use with cost-effective high-resolution interrogators, allowing both a high sensitivity and a low limit of detection to be reached in immunosensing. This paper will review recent progress made in this field with different kinds of gratings: uniform, tilted and eccentric short-period gratings as well as long-period fiber gratings. Practical cases will be reported, showing that such sensors can be used in very small volumes of analytes and even possibly applied to in vivo diagnosis.

  6. Basic study on radiation distribution sensing with normal optical fiber

    International Nuclear Information System (INIS)

    Naka, R.; Kawarabayashi, J.; Uritani, A.; Iguchi, T.; Kaneko, J.; Takeuchi, H.; Kakuta, T.

    2000-01-01

    Recently, some methods of radiation distribution sensing with optical fibers have been proposed. These methods employ scintillating fibers or scintillators with wavelength-shifting fibers. The positions of radiation interactions are detected by applying a time-of-flight (TOF) technique to the scintillation photon propagation. In the former method, the attenuation length for the scintillation photons in the scintillating fiber is relatively short, so that the operating length of the sensor is limited to several meters. In the latter method, a radiation distribution cannot continuously be obtained but discretely. To improve these shortcomings, a normal optical fiber made of polymethyl methacrylate (PMMA) is used in this study. Although the scintillation efficiency of PMMA is very low, several photons are emitted through interaction with a radiation. The fiber is transparent for the emitted photons to have a relatively long operating length. A radiation distribution can continuously be obtained. This paper describes a principle of the position sensing method based on the time of flight technique and preliminary results obtained for 90 Sr- 90 Y beta rays, 137 Cs gamma rays, and 14 MeV neutrons. The spatial resolutions for the above three kinds of radiations are 0.30 m, 0.37 m, 0.13 m, and the detection efficiencies are 1.1 x 10 -3 , 1.6 x 10 -7 , 5.4 x 10 -6 , respectively, with 10 m operation length. The results of a spectroscopic study on the optical property of the fiber are also described. (author)

  7. Plasmonic Optical Fiber-Grating Immunosensing: A Review

    Directory of Open Access Journals (Sweden)

    Tuan Guo

    2017-11-01

    Full Text Available Plasmonic immunosensors are usually made of a noble metal (in the form of a film or nanoparticles on which bioreceptors are grafted to sense analytes based on the antibody/antigen or other affinity mechanism. Optical fiber configurations are a miniaturized counterpart to the bulky Kretschmann prism and allow easy light injection and remote operation. To excite a surface plasmon (SP, the core-guided light is locally outcoupled. Unclad optical fibers were the first configurations reported to this end. Among the different architectures able to bring light in contact with the surrounding medium, a great quantity of research is today being conducted on metal-coated fiber gratings photo-imprinted in the fiber core, as they provide modal features that enable SP generation at any wavelength, especially in the telecommunication window. They are perfectly suited for use with cost-effective high-resolution interrogators, allowing both a high sensitivity and a low limit of detection to be reached in immunosensing. This paper will review recent progress made in this field with different kinds of gratings: uniform, tilted and eccentric short-period gratings as well as long-period fiber gratings. Practical cases will be reported, showing that such sensors can be used in very small volumes of analytes and even possibly applied to in vivo diagnosis.

  8. Optical Fiber Nanotips Coated with Molecular Beacons for DNA Detection

    Directory of Open Access Journals (Sweden)

    Ambra Giannetti

    2015-04-01

    Full Text Available Optical fiber sensors, thanks to their compactness, fast response and real-time measurements, have a large impact in the fields of life science research, drug discovery and medical diagnostics. In recent years, advances in nanotechnology have resulted in the development of nanotools, capable of entering the single cell, resulting in new nanobiosensors useful for the detection of biomolecules inside living cells. In this paper, we provide an application of a nanotip coupled with molecular beacons (MBs for the detection of DNA. The MBs were characterized by hybridization studies with a complementary target to prove their functionality both free in solution and immobilized onto a solid support. The solid support chosen as substrate for the immobilization of the MBs was a 30 nm tapered tip of an optical fiber, fabricated by chemical etching. With this set-up promising results were obtained and a limit of detection (LOD of 0.57 nM was reached, opening up the possibility of using the proposed nanotip to detect mRNAs inside the cytoplasm of living cells.

  9. Performance and safety of holmium: YAG laser optical fibers.

    Science.gov (United States)

    Knudsen, Bodo E; Glickman, Randolph D; Stallman, Kenneth J; Maswadi, Saher; Chew, Ben H; Beiko, Darren T; Denstedt, John D; Teichman, Joel M H

    2005-11-01

    Lower-pole ureteronephroscopy requires transmission of holmium:YAG energy along a deflected fiber. Current ureteroscopes are capable of high degrees of deflection, which may stress laser fibers beyond safe limits during lower-pole use. We hypothesized that optical fiber and safety measures differ among manufacturers. Small (200-273-microm) and medium-diameter (300-400-microm) Ho:YAG fibers were tested in a straight and 180 degrees bent configuration. Energy transmission was measured by an energy detector. Fiber durability was assessed by firing the laser in sequentially tighter bending diameters. The fibers were bent to 180 degrees with a diameter of 6 cm and run at 200- to 4000-mJ pulse energy to determine the minimum energy required to fracture the fiber. The bending diameter was decreased by 1-cm increments and testing repeated until a bending diameter of 1 cm was reached. The maximum deflection of the ACMI DUR-8E ureteroscope with each fiber in the working channel was recorded. The flow rate through the working channel of the DUR-8E was measured for each fiber. The mean energy transmission differed among fibers (P < 0.001). The Lumenis SL 200 and the InnovaQuartz 400 were the best small and medium-diameter fibers, respectively, in resisting thermal breakdown (P < 0.01). The Dornier Lightguide Super 200 fractured repeatedly at a bend diameter of 2 cm and with the lowest energy (200 mJ). The other small fibers fractured only at a bend diameter of 1 cm. The Sharplan 200 and InnovaQuartz Sureflex 273T were the most flexible fibers, the Lumenis SL 365 the least. The flow rate was inversely proportional to four times the power of the diameter of the fiber. Optical performance and safety differ among fibers. Fibers transmit various amounts of energy to their cladding when bent. During lower-pole nephroscopy with the fiber deflected, there is a risk of fiber fracture from thermal breakdown and laser-energy transmission to the endoscope. Some available laser fibers

  10. Optical fiber head for providing lateral viewing

    Science.gov (United States)

    Everett, Matthew J.; Colston, Billy W.; James, Dale L.; Brown, Steve; Da Silva, Luiz

    2002-01-01

    The head of an optical fiber comprising the sensing probe of an optical heterodyne sensing device includes a planar surface that intersects the perpendicular to axial centerline of the fiber at a polishing angle .theta.. The planar surface is coated with a reflective material so that light traveling axially through the fiber is reflected transverse to the fiber's axial centerline, and is emitted laterally through the side of the fiber. Alternatively, the planar surface can be left uncoated. The polishing angle .theta. must be no greater than 39.degree. or must be at least 51.degree.. The emitted light is reflected from adjacent biological tissue, collected by the head, and then processed to provide real-time images of the tissue. The method for forming the planar surface includes shearing the end of the optical fiber and applying the reflective material before removing the buffer that circumscribes the cladding and the core.

  11. Strength measurement of optical fibers by bending

    Science.gov (United States)

    Srubshchik, Leonid S.

    1999-01-01

    A two-point bending technique has been used not only to measure the breaking stress of optical fiber but also to predict its static and dynamic fatigue. The present theory of this test is based on elastica theory of rod. However, within the limits of elastica theory the tensile and shear stresses cannot be determined. In this paper we study dynamic and static problems for optical fiber in the two- point bending test on the base of geometrically exact theory in which rod can suffer flexure, extension, and shear. We obtain the governing partial differential equations taking into account the fact that the lateral motion of the fiber is restrained by the presence of flat parallel plates. We develop the computational methods for solving the initial and equilibrium free-boundary nonlinear planar problems. We derive the formulas for predicting of the tensile strength from strength in the bending and calculate one example.

  12. Scintillating Optical Fiber Imagers for biology

    International Nuclear Information System (INIS)

    Mastrippolito, R.

    1990-01-01

    S.O.F.I (Scintillating Optical Fiber Imager) is a detector developed to replace the autoradiographic films used in molecular biology for the location of radiolabelled ( 32 P) DNA molecules in blotting experiments. It analyses samples on a 25 x 25 cm 2 square area still 25 times faster than autoradiographic films, with a 1.75 and 3 mm resolution for two orthogonal directions. This device performs numerised images with a dynamic upper than 100 which allows the direct quantitation of the analysed samples. First, this thesis describes the S.O.F.I. development (Scintillating Optical Fibers, coding of these fibers and specific electronic for the treatment of the Multi-Anode Photo-Multiplier signals) and experiments made in collaboration with molecular biology laboratories. In a second place, we prove the feasibility of an automatic DNA sequencer issued from S.O.F.I [fr

  13. Microbending losses in multimode optical fibers

    International Nuclear Information System (INIS)

    Hussain, A.; Mudassar, A.A.; Hamza, M.Y.; Ikram, M.

    2003-01-01

    Microbending losses of optical fiber have been studied for different amplitude and shape of the deformer. Experimental results show that grooves of angel 60 degree cause more losses as compared to the grooves 90 degree. Intensity modulation induced by micro bends is considered as transudation mechanism for detecting environmental changes such as pressure, temperature, acceleration and magnetic and electric fields. An accelerometer has been designed on this principle and tested up to the acceleration of 65g. (author)

  14. Spectrally efficient polymer optical fiber transmission

    Science.gov (United States)

    Randel, Sebastian; Bunge, Christian-Alexander

    2011-01-01

    The step-index polymer optical fiber (SI-POF) is an attractive transmission medium for high speed communication links in automotive infotainment networks, in industrial automation, and in home networks. Growing demands for quality of service, e.g., for IPTV distribution in homes and for Ethernet based industrial control networks will necessitate Gigabit speeds in the near future. We present an overview on recent advances in the design of spectrally efficient and robust Gigabit-over-SI-POF transmission systems.

  15. Pulsed laser damage to optical fibers

    International Nuclear Information System (INIS)

    Allison, S.W.; Gillies, G.T.; Magnuson, D.W.; Pagano, T.S.

    1985-01-01

    This paper describes some observations of pulsed laser damage to optical fibers with emphasis on a damage mode characterized as a linear fracture along the outer core of a fiber. Damage threshold data are presented which illustrate the effects of the focusing lens, end-surface preparation, and type of fiber. An explanation based on fiber-beam misalignment is given and is illustrated by a simple experiment and ray trace

  16. Chalcogenide glass hollow core microstructured optical fibers

    Directory of Open Access Journals (Sweden)

    Vladimir S. eShiryaev

    2015-03-01

    Full Text Available The recent developments on chalcogenide glass hollow core microstructured optical fibers (HC-MOFs are presented. The comparative analysis of simulated optical properties for chalcogenide HC-MOFs of negative-curvature with different size and number of capillaries is given. The technique for the manufacture of microstructured chalcogenide preforms, which includes the assembly of the substrate glass tube and 8-10 capillaries, is described. Further trends to improve the optical transmission in chalcogenide NCHCFs are considered.

  17. Optic Fibers as a Broadcasting Media

    Directory of Open Access Journals (Sweden)

    Jusuf QARKAXHIJA

    2018-04-01

    Full Text Available Fast brodcasting of an information is always a challange from our daily activities. Through fast broadcasting of the information always created pre-eminence in military activities, business, researching, etc. From ancient times we know that information was orally and hand in hand broadcasted which in most of the times casused in loss of information and due to this also in loss of activities which are mentioned above. Due to information technology notably computer networks and internet overtime information started broadcasting faster. Information started broadcasting through copper wires and through wireless. Big applications started to develop with the increased use of Internet, high quality broadcasting (HD, video on demand broadcasting (VoD, triple pay broadcasting (three services on a medium, etc., then these two mediums couldn’t complete all these requests. Therfore after these problems, optic fiber began to be used as a broadcasting medium which eleminated all the defects of other mediums. Importance of this paper work is telling developing stages of optic fiber, it’s characteristics and it’s losses. Then it is shown that which devises enforce the signal of fibers and in the end all three mediums that we mentioned are compared on the basis of attributes. Findings form the paper will only enforce that knowledge we had before about optic fiber, the best broadcasting medium.

  18. Single- and two-phase flow characterization using optical fiber bragg gratings.

    Science.gov (United States)

    Baroncini, Virgínia H V; Martelli, Cicero; da Silva, Marco José; Morales, Rigoberto E M

    2015-03-17

    Single- and two-phase flow characterization using optical fiber Bragg gratings (FBGs) is presented. The sensor unit consists of the optical fiber Bragg grating positioned transversely to the flow and fixed in the pipe walls. The hydrodynamic pressure applied by the liquid or air/liquid flow to the optical fiber induces deformation that can be detected by the FBG. Given that the applied pressure is directly related to the mass flow, it is possible to establish a relationship using the grating resonance wavelength shift to determine the mass flow when the flow velocity is well known. For two phase flows of air and liquid, there is a significant change in the force applied to the fiber that accounts for the very distinct densities of these substances. As a consequence, the optical fiber deformation and the correspondent grating wavelength shift as a function of the flow will be very different for an air bubble or a liquid slug, allowing their detection as they flow through the pipe. A quasi-distributed sensing tool with 18 sensors evenly spread along the pipe is developed and characterized, making possible the characterization of the flow, as well as the tracking of the bubbles over a large section of the test bed. Results show good agreement with standard measurement methods and open up plenty of opportunities to both laboratory measurement tools and field applications.

  19. Detection of Ultrasonic Stress Waves in Structures Using 3D Shaped Optic Fiber Based on a Mach-Zehnder Interferometer.

    Science.gov (United States)

    Lan, Chengming; Zhou, Wensong; Xie, Yawen

    2018-04-16

    This work proposes a 3D shaped optic fiber sensor for ultrasonic stress waves detection based on the principle of a Mach–Zehnder interferometer. This sensor can be used to receive acoustic emission signals in the passive damage detection methods and other types of ultrasonic signals propagating in the active damage detection methods, such as guided wave-based methods. The sensitivity of an ultrasonic fiber sensor based on the Mach–Zehnder interferometer mainly depends on the length of the sensing optical fiber; therefore, the proposed sensor achieves the maximum possible sensitivity by wrapping an optical fiber on a hollow cylinder with a base. The deformation of the optical fiber is produced by the displacement field of guided waves in the hollow cylinder. The sensor was first analyzed using the finite element method, which demonstrated its basic sensing capacity, and the simulation signals have the same characteristics in the frequency domain as the excitation signal. Subsequently, the primary investigations were conducted via a series of experiments. The sensor was used to detect guided wave signals excited by a piezoelectric wafer in an aluminum plate, and subsequently it was tested on a reinforced concrete beam, which produced acoustic emission signals via impact loading and crack extension when it was loaded to failure. The signals obtained from a piezoelectric acoustic emission sensor were used for comparison, and the results indicated that the proposed 3D fiber optic sensor can detect ultrasonic signals in the specific frequency response range.

  20. Detection of Ultrasonic Stress Waves in Structures Using 3D Shaped Optic Fiber Based on a Mach–Zehnder Interferometer

    Science.gov (United States)

    Xie, Yawen

    2018-01-01

    This work proposes a 3D shaped optic fiber sensor for ultrasonic stress waves detection based on the principle of a Mach–Zehnder interferometer. This sensor can be used to receive acoustic emission signals in the passive damage detection methods and other types of ultrasonic signals propagating in the active damage detection methods, such as guided wave-based methods. The sensitivity of an ultrasonic fiber sensor based on the Mach–Zehnder interferometer mainly depends on the length of the sensing optical fiber; therefore, the proposed sensor achieves the maximum possible sensitivity by wrapping an optical fiber on a hollow cylinder with a base. The deformation of the optical fiber is produced by the displacement field of guided waves in the hollow cylinder. The sensor was first analyzed using the finite element method, which demonstrated its basic sensing capacity, and the simulation signals have the same characteristics in the frequency domain as the excitation signal. Subsequently, the primary investigations were conducted via a series of experiments. The sensor was used to detect guided wave signals excited by a piezoelectric wafer in an aluminum plate, and subsequently it was tested on a reinforced concrete beam, which produced acoustic emission signals via impact loading and crack extension when it was loaded to failure. The signals obtained from a piezoelectric acoustic emission sensor were used for comparison, and the results indicated that the proposed 3D fiber optic sensor can detect ultrasonic signals in the specific frequency response range. PMID:29659540

  1. Vertical Strain Measured in the Mississippi River Delta Using Borehole Optical Fiber Strainmeters

    Science.gov (United States)

    Hatfield, W.; Allison, M. A.; Bridgeman, J.; Dixon, T. H.; Elliott, D.; Steckler, M. S.; Tornqvist, T. E.; Williams, K.; Wyatt, F. K.; Zumberge, M. A.

    2017-12-01

    Three boreholes in the Mississippi River Delta, at a site 2 km from the river near Myrtle Grove, Louisiana, have been instrumented with optical fiber strainmeters. The boreholes extend to depths of 9 m, 24 m, and 37 m. Each contains an optical fiber strainmeter that records the displacement between a steel surface casing and a termination fixture cemented into the bottom of each borehole. The strainmeters consist of an optical fiber cable stretched to a length 0.2% longer than its unstressed condition. An optical interferometer is formed between each sensing fiber and a second optical fiber of equal length wrapped on a reference mandrel housed in a sonde in the wellhead casing. This arrangement relaxes stability requirements on the light source. A signal processing unit samples the interference fringe signals 50,000 times per second and calculates the optical phase shift, providing a displacement record precise to a few nm or strain sensitivity of better than 1 nanostrain. The sensors operate from solar power and transmit the data (decimated to 20 samples per second) to an archiving system via a cell phone modem. To mitigate against the effects of temperature variations, a second optical fiber sensor with a different temperature is operated in parallel with the first, sharing the same cable and processing sonde. Records from the two fibers allow the separation of optical length changes caused by temperature from the earth strain. The three individual systems provide an unprecedented measure of soil compaction. Over short periods we observe sub-micron signals such as teleseisms, and over the long term we have observed stability at the tenths of a mm level. The site has shown no compaction or subsidence greater than a few tenths of a mm over the last year, highlighting the value of strainmeters over other techniques that can not resolve such small signals. Two of the sensors began operating in July of 2016, the third began operation in May of 2017.

  2. Microstructured Optical Fiber-based Biosensors: Reversible and Nanoliter-Scale Measurement of Zinc Ions.

    Science.gov (United States)

    Heng, Sabrina; McDevitt, Christopher A; Kostecki, Roman; Morey, Jacqueline R; Eijkelkamp, Bart A; Ebendorff-Heidepriem, Heike; Monro, Tanya M; Abell, Andrew D

    2016-05-25

    Sensing platforms that allow rapid and efficient detection of metal ions would have applications in disease diagnosis and study, as well as environmental sensing. Here, we report the first microstructured optical fiber-based biosensor for the reversible and nanoliter-scale measurement of metal ions. Specifically, a photoswitchable spiropyran Zn(2+) sensor is incorporated within the microenvironment of a liposome attached to microstructured optical fibers (exposed-core and suspended-core microstructured optical fibers). Both fiber-based platforms retains high selectivity of ion binding associated with a small molecule sensor, while also allowing nanoliter volume sampling and on/off switching. We have demonstrated that multiple measurements can be made on a single sample without the need to change the sensor. The ability of the new sensing platform to sense Zn(2+) in pleural lavage and nasopharynx of mice was compared to that of established ion sensing methodologies such as inductively coupled plasma mass spectrometry (ICP-MS) and a commercially available fluorophore (Fluozin-3), where the optical-fiber-based sensor provides a significant advantage in that it allows the use of nanoliter (nL) sampling when compared to ICP-MS (mL) and FluoZin-3 (μL). This work paves the way to a generic approach for developing surface-based ion sensors using a range of sensor molecules, which can be attached to a surface without the need for its chemical modification and presents an opportunity for the development of new and highly specific ion sensors for real time sensing applications.

  3. Detection of gamma rays using scintillation optical fibers

    International Nuclear Information System (INIS)

    Park, J. W.; Hong, S. B.

    2002-01-01

    Scintillating optical fibers have several advantages over other conventional materials used for radiation detection. We have used glass and plastic scintillating fibers to detect gamma rays emitted from 60 Co and 137 Cs, and beta rays from 90 Sr. The sensors are constructed of single strand or multi-strand fibers of 1 mm diameter. The glass scintillating fiber used contains cerium-activated lithium-silicate as scintillating material and the plastic scintillating fiber used is Bicron model BCF-12. In this paper, we report the pulse-height spectra obtained by both sensor types, and analyze them in the aspect of their usability for radiation detectors. Our investigation suggests that the glass fiber can be used to develop gamma ray detectors which will function in high and low gamma ray flux environments. Use of the sensor for the beta ray detection was not satisfactory. The plastic fiber sensor did not work satisfactorily for the weak gamma sources, but did produce somewhat promising results. The scintillating plastic fiber offers some feasibility as beta ray sensor material

  4. Extreme temperature sensing using brillouin scattering in optical fibers

    CERN Document Server

    Fellay, Alexandre

    Stimulated Brillouin scattering in silica-based optical fibers may be considered from two different and complementary standpoints. For a physicist, this interaction of light and pressure wave in a material, or equivalently in quantum theory terms between photons and phonons, gives some glimpses of the atomic structure of the solid and of its vibration modes. For an applied engineer, the same phenomenon may be put to good use as a sensing mechanism for distributed measurements, thanks to the dependence of the scattered light on external parameters such as the temperature, the pressure or the strain applied to the fiber. As far as temperature measurements are concerned, Brillouin-based distributed sensors have progressively gained wide recognition as efficient systems, even if their rather high cost still restricts the number of their applications. Yet they are generally used in a relatively narrow temperature range around the usual ambient temperature; in this domain, the frequency of the scattered light incre...

  5. Current measurements by Faraday rotation in single mode optical fibers

    International Nuclear Information System (INIS)

    Chandler, G.I.; Jahoda, F.C.

    1984-01-01

    Development of techniques for measuring magnetic fields and currents by Faraday rotation in single-mode optical fibers has continued. We summarize the results of attempts to measure the toroidal plasma current in the ZT-40 Reversed-Field-Pinch using multi-turn fiber coils. The fiber response is reproducible and in accord with theory, but the amount and distribution of the stress-induced birefringence in this case are such that prediction of the sensor response at low currents is difficult if not impossible. The low-current difficulty can be overcome by twisting the fiber to induce a circular birefringence bias. We report the results of auxiliary experiments with a fiber that has been twisted with 15 turns per meter and then re-coated to lock the twist in place

  6. Programmable current source for diode lasers stabilized optical fiber

    International Nuclear Information System (INIS)

    Gomez, J.; Camas, J.; Garcia, L.

    2012-01-01

    In this paper, we present the electronic design of a programmable stabilized current source. User can access to the source through a password, which, it has a database with the current and voltage operating points. This source was successfully used as current source in laser diode in optical fiber sensors. Variations in the laser current were carried out by a monitoring system and a control of the Direct Current (DC), which flowing through a How land source with amplifier. The laser current can be stabilized with an error percent of ± 1 μA from the threshold current (Ith) to its maximum operation current (Imax) in DC mode. The proposed design is reliable, cheap, and its output signal of stabilized current has high quality. (Author)

  7. Polymer optical fiber tapering using chemical solvent and polishing

    Science.gov (United States)

    Supian, L. S.; Syuhaimi Ab-Rahman, Mohd; Arsad, Norhana

    2017-11-01

    A method for developing polymer optical fiber (POF) directional coupler is introduced where the initial procedure includes using chemical solvent to remove the cladding, and bare out the core in order to align the unclad center of the fiber with other similar fiber to develop a coupler. The process is safe, simple, inexpensive and require low operation skill. The etched fiber offers improvement to the performance of various POF devices, i.e, couplers and sensors. Instead of relying only on silica or glass fiber, POF now can be used as an alternative to improve the network performance in short distance communication system. The measurement parameters laid out offer great outcomes. However, the couplers intended to be developed is yet to be realized, where deeper research and various experiments are needed in order to develop a simple but optimum performance coupler that can be used for various applications.

  8. Polymer optical fiber tapering using chemical solvent and polishing

    Directory of Open Access Journals (Sweden)

    Supian L. S.

    2017-01-01

    Full Text Available A method for developing polymer optical fiber (POF directional coupler is introduced where the initial procedure includes using chemical solvent to remove the cladding, and bare out the core in order to align the unclad center of the fiber with other similar fiber to develop a coupler. The process is safe, simple, inexpensive and require low operation skill. The etched fiber offers improvement to the performance of various POF devices, i.e, couplers and sensors. Instead of relying only on silica or glass fiber, POF now can be used as an alternative to improve the network performance in short distance communication system. The measurement parameters laid out offer great outcomes. However, the couplers intended to be developed is yet to be realized, where deeper research and various experiments are needed in order to develop a simple but optimum performance coupler that can be used for various applications.

  9. Application technology for optical fiber in nuclear facilities

    International Nuclear Information System (INIS)

    Lee, Jong Min; Kim, Chul Jung; Lee, Yong Bum; Kim, Woong Ki; Yoon, Tae Seob; Sohn, Surg Won; Kim, Chang Hoi; Hwang, Suk Yong; Baik, Sung Hum; Kwon, Seong Ouk

    1987-12-01

    Lately, the optical fiber increasingly used in such adverse environments as nuclear power plant, radiation facilities because of their endurant properties against heat, radiation, corrosion, etc. Moreover, the transmission of signal through optical fiber does not induce interference from the electromagnetic wave. Basic theory about the optical fiber technology was studied and the developed techniques for nuclear facilities were reviewed. Since the radiations change the characteristics of the optical fiber, the effects of γ-ray irradiation on single mode and multimode optical fiber were examined. The image transmission system through optical fiber bundle was designed, constructed, and tested. Its software system was also updated. It can be used for remote internal inspection in adverse environment. (Author)

  10. Experimental study on distributed optical fiber-based approach monitoring saturation line in levee engineering

    Science.gov (United States)

    Su, Huaizhi; Li, Hao; Kang, Yeyuan; Wen, Zhiping

    2018-02-01

    Seepage is one of key factors which affect the levee engineering safety. The seepage danger without timely detection and rapid response may likely lead to severe accidents such as seepage failure, slope instability, and even levee break. More than 90 percent of levee break events are caused by the seepage. It is very important for seepage behavior identification to determine accurately saturation line in levee engineering. Furthermore, the location of saturation line has a major impact on slope stability in levee engineering. Considering the structure characteristics and service condition of levee engineering, the distributed optical fiber sensing technology is introduced to implement the real-time observation of saturation line in levee engineering. The distributed optical fiber temperature sensor system (DTS)-based monitoring principle of saturation line in levee engineering is investigated. An experimental platform, which consists of DTS, heating system, water-supply system, auxiliary analysis system and levee model, is designed and constructed. The monitoring experiment of saturation line in levee model is implemented on this platform. According to the experimental results, the numerical relationship between moisture content and thermal conductivity in porous medium is identified. A line heat source-based distributed optical fiber method obtaining the thermal conductivity in porous medium is developed. A DTS-based approach is proposed to monitor the saturation line in levee engineering. The embedment pattern of optical fiber for monitoring saturation line is presented.

  11. The usage of optical fibers for damage detection in ballistic protection composite laminates

    Directory of Open Access Journals (Sweden)

    Živković Irena D.

    2006-01-01

    Full Text Available This paper describes the procedure of embedding fiber optic sensors in laminar thermoplastic composite material, as well as damage investigation after ballistic loading. Thermoplastic-reinforced composite materials were made for increased material damage resistance during ballistic loading. Damage inside the composite material was detected by observing the intensity drop of the light signal transmitted through the optical fibers. Experimental testing was carried out in order to observe and analyze the response of the material under various load conditions. Different types of Kevlar reinforced composite materials (thermoplastic, thermo reactive and thermoplastic with ceramic plate as the impact face were made. Material damage resistance during ballistic loading was investigated and compared. Specimens were tested under multiple load conditions. The opto-electronic part of the measurement system consists of two light-emitting diodes as light sources for the optical fibers, and two photo detectors for the light intensity measurement. The output signal was acquired from photo detectors by means of a data acquisition board and personal computer. The measurements showed an intensity drop of the transmitted light signal as a result of the applied loading on composite structure for all the optical fibers. All the diagrams show similar behavior of the light signal intensity. In fact, all of them may be divided into three zones: the zone of penetration of the first composite layer, the bullet traveling zone through the composite material till its final stop, and the material relaxation zone. The attenuation of the light signal intensity during impact is caused by the influence of the applied dynamic stress on the embedded optical fibers. The applied stress caused micro bending of the optical fiber, changes in the shape of the cross-section and the unequal changes of the indices of refraction of the core and cladding due to the stress-optic effect. The

  12. Lasers and optical fibers in medicine

    CERN Document Server

    Katzir, Abraham

    1993-01-01

    The increasing use of fiber optics in the field of medicine has created a need for an interdisciplinary perspective of the technology and methods for physicians as well as engineers and biophysicists. This book presents a comprehensive examination of lasers and optical fibers in an hierarchical, three-tier system. Each chapter is divided into three basic sections: the Fundamentals section provides an overview of basic concepts and background; the Principles section offers an in-depth engineering approach; and the Advances section features specific information on systems an

  13. Optical fiber telecommunications systems and networks

    CERN Document Server

    Kaminow, Ivan; Willner, Alan E

    2013-01-01

    Optical Fiber Telecommunications VI (A&B) is the sixth in a series that has chronicled the progress in the R&D of lightwave communications since the early 1970s. Written by active authorities from academia and industry, this edition brings a fresh look to many essential topics, including devices, subsystems, systems and networks. A central theme is the enabling of high-bandwidth communications in a cost-effective manner for the development of customer applications. These volumes are an ideal reference for R&D engineers and managers, optical systems implementers, university researchers and s

  14. Optical fiber telecommunications components and subsystems

    CERN Document Server

    Kaminow, Ivan; Willner, Alan E

    2013-01-01

    Optical Fiber Telecommunications VI (A&B) is the sixth in a series that has chronicled the progress in the R&D of lightwave communications since the early 1970s. Written by active authorities from academia and industry, this edition brings a fresh look to many essential topics, including devices, subsystems, systems and networks. A central theme is the enabling of high-bandwidth communications in a cost-effective manner for the development of customer applications. These volumes are an ideal reference for R&D engineers and managers, optical systems implementers, university researchers and s

  15. Collapsed optical fiber: A novel method for improving thermoluminescence response of optical fiber

    Energy Technology Data Exchange (ETDEWEB)

    Mahdiraji, G. Amouzad, E-mail: ghafour@um.edu.my [Integrated Lightwave Research Group, Department of Electrical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Adikan, F.R. Mahamd [Integrated Lightwave Research Group, Department of Electrical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Bradley, D.A. [Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom); Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2015-05-15

    A new technique is shown to provide improved thermoluminescence (TL) response from optical fibers, based on collapsing down hollow capillary optical fibers (COF) into flat fibers (FF), producing fused inner walls and consequent defects generation. Four different fused silica preform tubes are used to fabricate in-house COFs and FFs, i.e., ultra-pure (F300), relatively pure silica (PS), germanium-doped (Ge), and Ge–Boron-doped (GeB). The optical fibers are then subjected to 6 MeV electron irradiation. While the results show similar TL response from F300-COF and -FF, the TL response of PS-COF is improved by a factor of 6 by collapsing it down to a FF. By doping Ge into the F300 tube, the TL response of the resultant Ge-COF shows an improvement of 3 times over that of F300-COF, while an improvement of a factor of 12 is obtained by producing a Ge-FF. In GeB preform, by collapsing the capillary fiber into a FF, an improvement in TL response of 31 times that of GeB-COF is obtained. TL glow curve analysis shows an additional peak to be generated in the FFs compared to that observed in the COFs. The TL intensity value of the new peak is significantly increased in the doped FFs compared to the undoped FFs. The results suggest that defects generation occurs as a result of the fusing/collapsing technique, providing a TL response from the optical fibers that can substantially improve upon that of existing TL system sensitivities. - Highlights: • A new method for increasing TL response of optical fiber is presented. • By collapsing capillary fiber wall surface, TL response of the fiber increased. • By adding impurity in the collapsing area, TL response significantly improved.

  16. Enzyme-enhanced fluorescence detection of DNA on etched optical fibers.

    Science.gov (United States)

    Niu, Shu-yan; Li, Quan-yi; Ren, Rui; Zhang, Shu-sheng

    2009-05-15

    A novel DNA biosensor based on enzyme-enhanced fluorescence detection on etched optical fibers was developed. The hybridization complex of DNA probe and biotinylated target was formed on the etched optical fiber, and was then bound with streptavidin labeled horseradish peroxidase (streptavidin-HRP). The target DNA was quantified through the fluorescent detection of bi-p,p'-4-hydroxyphenylacetic acid (DBDA) generated from the substrate 4-hydroxyphenylacetic acid (p-HPA) under the catalysis of HRP, with a detection limit of 1 pM and a linear range from 1.69 pM to 169 pM. It is facile to regenerate this sensor through surface treatment with concentrated urea solution. It was discovered that the sensor can retain 70% of its original activity after three detection-regeneration cycles.

  17. Teaching stellar interferometry with polymer optical fibers

    Science.gov (United States)

    Illarramendi, M. A.; Arregui, L.; Zubia, J.; Hueso, R.; Sanchez-Lavega, A.

    2017-08-01

    In this manuscript we show the design of a simple experiment that reproduces the operation of the Michelson stellar interferometer by using step-index polymer optical fibers. The emission of stellar sources, single or binary stars, has been simulated by the laser light emerging from the output surface of the 2 meter-long polymer optical fiber. This light has an emission pattern that is similar to the emission pattern of stellar sources - circular, uniform, spatially incoherent, and quasi-monochromatic. Light coming from the fiber end faces passes through two identical pinholes located on a lid covering the objective of a small telescope, thus producing interference. Interference fringes have been acquired using a camera that is coupled to a telescope. The experiments have been carried out both outdoors in the daytime and indoors. By measuring the fringe visibilities, we have determined the size of our artificial stellar sources and the distance between them, when placing them at distances of 54 m from the telescope in the indoor measurements and of 75 m in the outdoor ones.

  18. Development of an Optical Fiber-Based MR Compatible Gamma Camera for SPECT/MRI Systems

    Science.gov (United States)

    Yamamoto, Seiichi; Watabe, Tadashi; Kanai, Yasukazu; Watabe, Hiroshi; Hatazawa, Jun

    2015-02-01

    Optical fiber is a promising material for integrated positron emission tomography (PET) and magnetic resonance imaging (MRI) PET/MRI systems. Because its material is plastic, it has no interference between MRI. However, it is unclear whether this material can also be used for a single photon emission tomography (SPECT)/MRI system. For this purpose, we developed an optical fiber-based block detector for a SPECT/MRI system and tested its performance by combining 1.2 ×1.2 ×6 mm Y2SiO5 (YSO) pixels into a 15 ×15 block and was coupled it to an optical fiber image guide that used was 0.5-mm in diameter with 80-cm long double clad fibers. The image guide had 22 ×22 mm rectangular input and an equal size output. The input of the optical fiber-based image guide was bent at 90 degrees, and the output was optically coupled to a 1-in square high quantum efficiency position sensitive photomultiplier tube (HQE-PSPMT). The parallel hole, 7-mm-thick collimator made of tungsten plastic was mounted on a YSO block. The diameter of the collimator holes was 0.8 mm which was positioned one-to-one coupled to the YSO pixels. We evaluated the intrinsic and system performances. We resolved most of the YSO pixels in a two-dimensional histogram for Co-57 gamma photons (122-keV) with an average peak-to-value ratio of 1.5. The energy resolution was 38% full-width at half-maximum (FWHM). The system resolution was 1.7-mm FWHM, 1.5 mm from the collimator surface, and the sensitivity was 0.06%. Images of a Co-57 point source could be successfully obtained inside 0.3 T MRI without serious interference. We conclude that the developed optical fiber-based YSO block detector is promising for SPECT/MRI systems.

  19. Damage detection in laminar thermoplastic composite materials by means of embedded optical fibers

    Directory of Open Access Journals (Sweden)

    Kojović Aleksandar M.

    2006-01-01

    Full Text Available This paper investigates the possibility of applying optical fibers as sensors for investigating low energy impact damage in laminar thermoplastic composite materials, in real time. Impact toughness testing by a Charpy impact pendulum with different loads was conducted in order to determine the method for comparative measurement of the resulting damage in the material. For that purpose intensity-based optical fibers were built in to specimens of composite materials with Kevlar 129 (the DuPont registered trade-mark for poly(p-phenylene terephthalamide woven fabric as reinforcement and thermoplastic PVB (poly(vinyl butyral as the matrix. In some specimens part of the layers of Kevlar was replaced with metal mesh (50% or 33% of the layers. Experimental testing was conducted in order to observe and analyze the response of the material under multiple low-energy impacts. Light from the light-emitting diode (LED was launched to the embedded optical fiber and was propagated to the phototransistor-based photo detector. During each impact, the signal level, which is proportional to the light intensity in the optical fiber, drops and then slowly recovers. The obtained signals were analyzed to determine the appropriate method for real time damage monitoring. The major part of the damage occurs during impact. The damage reflects as a local, temporary release of strain in the optical fiber and an increase of the signal level. The obtained results show that intensity-based optical fibers could be used for measuring the damage in laminar thermoplastic composite materials. The acquired optical fiber signals depend on the type of material, but the same set of rules (relatively different, depending on the type of material could be specified. Using real time measurement of the signal during impact and appropriate analysis enables quantitative evaluation of the impact damage in the material. Existing methods in most cases use just the intensity of the signal before

  20. An inexpensive high-temperature optical fiber thermometer

    International Nuclear Information System (INIS)

    Moore, Travis J.; Jones, Matthew R.; Tree, Dale R.; Allred, David D.

    2017-01-01

    An optical fiber thermometer consists of an optical fiber whose tip is coated with a highly conductive, opaque material. When heated, this sensing tip becomes an isothermal cavity that emits like a blackbody. This emission is used to predict the sensing tip temperature. In this work, analytical and experimental research has been conducted to further advance the development of optical fiber thermometry. An inexpensive optical fiber thermometer is developed by applying a thin coating of a high-temperature cement onto the tip of a silica optical fiber. An FTIR spectrometer is used to detect the spectral radiance exiting the fiber. A rigorous mathematical model of the irradiation incident on the detection system is developed. The optical fiber thermometer is calibrated using a blackbody radiator and inverse methods are used to predict the sensing tip temperature when exposed to various heat sources. - Highlights: • An inexpensive coating for an optical fiber thermometer sensing tip is tested. • Inverse heat transfer methods are used to estimate the sensing tip temperature. • An FTIR spectrometer is used as the detector to test the optical fiber thermometer using various heat sources.

  1. Refractive index retrieving of polarization maintaining optical fibers

    Science.gov (United States)

    Ramadan, W. A.; Wahba, H. H.; Shams El-Din, M. A.; Abd El-Sadek, I. G.

    2018-01-01

    In this paper, the cross-section images, of two different types of polarization maintaining (PM) optical fibers, are employed to estimate the optical phase variation due to transverse optical rays passing through these optical fibers. An adaptive algorithm is proposed to recognize the different areas constituting the PM optical fibers cross-sections. These areas are scanned by a transverse beam to calculate the optical paths for given values of refractive indices. Consequently, the optical phases across the PM optical fibers could be recovered. PM optical fiber is immersed in a matching fluid and set in the object arm of Mach-Zehnder interferometer. The produced interferograms are analyzed to extract the optical phases caused by the PM optical fibers. The estimated optical phases could be optimized to be in good coincidence with experimentally extracted ones. This has been achieved through changing of the PM optical fibers refractive indices to retrieve the correct values. The correct refractive indices values are confirmed by getting the best fit between the estimated and the extracted optical phases. The presented approach is a promising one because it provides a quite direct and accurate information about refractive index, birefringence and beat length of PM optical fibers comparing with different techniques handle the same task.

  2. Modulational instability of short pulses in long optical fibers

    DEFF Research Database (Denmark)

    Shukla, P. K.; Juul Rasmussen, Jens

    1986-01-01

    The effect of time-derivative nonlinearity is incorporated into the study of the modulational instability of heat pulses propagating through long optical fibers. Conditions for soliton formation are discussed......The effect of time-derivative nonlinearity is incorporated into the study of the modulational instability of heat pulses propagating through long optical fibers. Conditions for soliton formation are discussed...

  3. Device for verification of seals by optical fibers

    International Nuclear Information System (INIS)

    Neuilly, M.; Guitaud, M.H.; Dufour, J.L.

    1993-01-01

    The seal is built around an optical fiber with a verification device. This device is made of a lighting source and photographic means supported by a rotating assembly which allow to take an image of each optical fiber end. These images are compared with reference images taken just after the sealing. (A.B.). 5 refs., 6 figs

  4. Simultaneous measurement of temperature and humidity with microstructured polymer optical fiber Bragg gratings

    DEFF Research Database (Denmark)

    Woyessa, Getinet; Pedersen, Jens Kristian Mølgaard; Fasano, Andrea

    2017-01-01

    A microstructured polymer optical fiber (mPOF) Bragg grating sensor system for the simultaneous measurement of temperature and relative humidity (RH) has been developed and characterized. The sensing head is based on two in-line fiber Bragg gratings recorded in a mPOF. The sensor system has a root...... mean square deviation of 1.04 % RH and 0.8 °C in the range 10 to 90% RH and 20 to 80 °C. The proposed sensor system is easy to fabricate, cheap and compact....

  5. Liquid droplet sensing using twisted optical fiber couplers fabricated by hydrofluoric acid flow etching

    Science.gov (United States)

    Son, Gyeongho; Jung, Youngho; Yu, Kyoungsik

    2017-04-01

    We report a directional-coupler-based refractive index sensor and its cost-effective fabrication method using hydrofluoric acid droplet wet-etching and surface-tension-driven liquid flows. The proposed fiber sensor consists of a pair of twisted tapered optical fibers with low excess losses. The fiber cores in the etched microfiber region are exposed to the surrounding medium for efficient interaction with the guided light. We observe that the etching-based low-loss fiber-optic sensors can measure the water droplet volume by detecting the refractive index changes of the surrounding medium around the etched fiber core region.

  6. Displacement sensing based on modal interference in polymer optical fibers with partially applied strain

    Science.gov (United States)

    Mizuno, Yosuke; Hagiwara, Sonoko; Kawa, Tomohito; Lee, Heeyoung; Nakamura, Kentaro

    2018-05-01

    Strain sensing based on modal interference in multimode fibers (MMFs) has been extensively studied, but no experimental or theoretical reports have been given as to how the system works when strain is applied not to the whole MMF but only to part of the MMF. Here, using a perfluorinated graded-index polymer optical fiber as the MMF, we investigate the strain sensing characteristics of this type of sensor when strain is partially applied to fiber sections with different lengths. The strain sensitivity dependence on the length of the strained section reveals that this strain sensor actually behaves as a displacement sensor.

  7. Experimental study of optical fibers influence on composite

    Science.gov (United States)

    Liu, Rong-Mei; Liang, Da-Kai

    2010-03-01

    Bending strength and elasticity modulus of composite, with and without embedded optical fibers, were experimentally studied. Two kinds of laminates, which were denoted as group 1 and group 2, were fabricated from an orthogonal woven glass/epoxy prepreg. Since the normal stress value becomes the biggest at the surface of a beam, the optical fibers were embedded at the outmost layer and were all along the loading direction. Four types of materials, using each kind of laminated prepreg respectively, were manufactured. The embedded optical fibers for the 4 material types were 0, 10, 30 and 50 respectively. Three-point bending tests were carried out on the produced specimens to study the influence of embedded optical fiber on host composite. The experimental results indicated that the materials in group 2 were more sensitive to the embedded optical fibers.

  8. Bente Boa, Torm, Denmark

    DEFF Research Database (Denmark)

    Wagtmann, Maria Anne

    2009-01-01

    At the beginning of July 2009, Maria Anne Wagtmann (Associate Professor, PhD, University of Southern Denmark) had the opportunity to interview Ms Bente Boa, a senior marine HR manager in the Danish ship owning firm TORM A/S' (http://www.torm.com/). Bente Boa is also chairwoman of the "The Sea...

  9. Evanescent field refractometry in planar optical fiber.

    Science.gov (United States)

    Holmes, Christopher; Jantzen, Alexander; Gray, Alan C; Gow, Paul C; Carpenter, Lewis G; Bannerman, Rex H S; Gates, James C; Smith, Peter G R

    2018-02-15

    This Letter demonstrates a refractometer in integrated optical fiber, a new optical platform that planarizes fiber using flame hydrolysis deposition (FHD). The unique advantage of the technology is survivability in harsh environments. The platform is mechanically robust, and can survive elevated temperatures approaching 1000°C and exposure to common solvents, including acetone, gasoline, and methanol. For the demonstrated refractometer, fabrication was achieved through wet etching an SMF-28 fiber to a diameter of 8 μm before FHD planarization. An external refractive index was monitored using fiber Bragg gratings (FBGs), written into the core of the planarized fiber. A direct comparison to alternative FBG refractometers is made, for which the developed platform is shown to have comparable sensitivity, with the added advantage of survivability in harsh environments.

  10. Microstructured optical fibers for gas sensing systems

    Science.gov (United States)

    Challener, William Albert; Choudhury, Niloy; Palit, Sabarni

    2017-10-17

    Microstructured optical fiber (MOF) includes a cladding extending a length between first and second ends. The cladding includes an inner porous microstructure that at least partially surrounds a hollow core. A perimeter contour of the hollow core has a non-uniform radial distance from a center axis of the cladding such that first segments of the cladding along the perimeter contour have a shorter radial distance from the center axis relative to second segments of the cladding along the perimeter contour. The cladding receives and propagates light energy through the hollow core, and the inner porous microstructure substantially confines the light energy within the hollow core. The cladding defines at least one port hole that extends radially from an exterior surface of the cladding to the hollow core. Each port hole penetrates the perimeter contour of the hollow core through one of the second segments of the cladding.

  11. Low-bending loss and single-mode operation in few-mode optical fiber

    Science.gov (United States)

    Yin, Ping; Wang, Hua; Chen, Ming-Yang; Wei, Jin; Cai, Zhi-Min; Li, Lu-Ming; Yang, Ji-Hai; Zhu, Yuan-Feng

    2016-10-01

    The technique of eliminating the higher-order modes in a few-mode optical fiber is proposed. The fiber is designed with a group of defect modes in the cladding. The higher-order modes in the fiber can be eliminated by bending the fiber to induce strong coupling between the defect modes and the higher-order modes. Numerical simulation shows the bending losses of the LP01 mode are lower than 1.5×10-4 dB/turn for the wavelength shorter than 1.625 μm. The proposed fiber can be bent multiple turns at small bending radius which are preferable for FTTH related applications.

  12. Radiation resistant characteristics of optical fibers

    International Nuclear Information System (INIS)

    Nakasuji, Masaaki; Tanaka, Gotaro; Watanabe, Minoru; Kyodo, Tomohisa; Mukunashi, Hiroaki

    1983-01-01

    It is required to develop the optical fibers with good radiation resistivity because the fibers cause the increase of transmission loss due to glass colouring when they are used under the presence of radiation such as γ-ray. Generally, it is known that SI (step index) fibers are more resistive to radiation than GI (graded index) fibers. However, since a wide band can not be obtained with SI fibers, the development of radiation resistive GI optical fibers is desirable. In this report, the production for trial of the GI fibers of fluorine-doped silica core, the examination of radiation effect on their optical transmission loss by exposing them to γ-ray, thermal and fast neutron beams and also of mechanical strength are described. The GI fibers of fluorine-doped silica core show better radiation resistivity than Ge-doped ones. The B- and F-doped GI fibers show small increase of loss due to γ-ray, but large increase of loss due to thermal neutron beam. This is supposed to be caused by the far greater neutron absorption cross-section of boron than that of other elements. Significant increase of loss was not recognized when 14 MeV fast neutrons (8.6 x 10 4 n/cm 2 .s) were applied by 1.8 x 10 9 n/cm 2 . It was found that ETFE-covered fiber cores generated fluorine-containing gas due to γ irradiation, and the strength was remarkably lowered, but the lowering of strength can be prevented by adding titanium-white to the covering material. (Wakatsuki, Y.)

  13. Radiation properties of two types of luminous textile devices containing plastic optical fibers

    Science.gov (United States)

    Selm, Bärbel; Rothmaier, Markus

    2007-05-01

    Luminous textiles have the potential to satisfy a need for thin and flexible light diffusers for treatment of intraoral cancerous tissue. Plastic optical fibers (POF) with diameters of 250 microns and smaller are used to make the textiles luminous. Usually light is supplied to the optical fiber at both ends. On the textile surface light emission occurs in a woven structure via damaged straight POFs, whereas the embroidered structure radiates the light out of macroscopically bent POFs. We compared the optical properties of these two types of textile diffusers using red light laser for the embroidery and light emitting diode (LED) for the woven structure as light sources, and found efficiencies for the luminous areas of the two samples of 19 % (woven) and 32 % (embroidery), respectively. It was shown that the efficiency can be greatly improved using an aluminium backing. Additional scattering layers lower the fluence rate by around 30 %. To analyse the homogeneity we took a photo of the illuminated surface using a 3CCD camera and found, for both textiles, a slightly skewed distribution of the dark and bright pixels. The interquartile range of brightness distribution of the embroidery is more than double as the woven structure.

  14. Medical Application of Free Electron Laser Trasmittance using Hollow Optical Fiber

    CERN Document Server

    Suzuki, Sachiko; Ishii, Katsonuri

    2004-01-01

    Mid-infrared Free Electron Laser (FEL) is expected as new application for biomedical surgery. However, delivery of MIR-FEL into the body is difficult because the common glass optical fibers have strong absorption at MIR region. A good operational and flexible line for FEL is required at medical field. A Hollow optical fiber is developed for IR laser and high-power laser delivery. We evaluated the fiber for FEL transmission line. This fiber is coated with cyclic olefin polymer (COP) and silver thin film on the inside of glass capillary tube. It is 700 μm-bore and 1m in lengths. The fiber transmission loss of the measured wavelength region of 5.5 μm to 12 μm is less than 1dB/m when the fiber is straight and 1.2 dB/m when bent to radius of 20 cm. Additionally, the output beam profile and the pulse structure is not so different form incidence beam. In conclusion, the fiber is suitable for delivery of the FEL energy for applications in medical and laser surgery.

  15. Review and perspective: Sapphire optical fiber cladding development for harsh environment sensing

    Science.gov (United States)

    Chen, Hui; Buric, Michael; Ohodnicki, Paul R.; Nakano, Jinichiro; Liu, Bo; Chorpening, Benjamin T.

    2018-03-01

    The potential to use single-crystal sapphire optical fiber as an alternative to silica optical fibers for sensing in high-temperature, high-pressure, and chemically aggressive harsh environments has been recognized for several decades. A key technological barrier to the widespread deployment of harsh environment sensors constructed with sapphire optical fibers has been the lack of an optical cladding that is durable under these conditions. However, researchers have not yet succeeded in incorporating a high-temperature cladding process into the typical fabrication process for single-crystal sapphire fibers, which generally involves seed-initiated fiber growth from the molten oxide state. While a number of advances in fabrication of a cladding after fiber-growth have been made over the last four decades, none have successfully transitioned to a commercial manufacturing process. This paper reviews the various strategies and techniques for fabricating an optically clad sapphire fiber which have been proposed and explored in published research. The limitations of current approaches and future prospects for sapphire fiber cladding are discussed, including fabrication methods and materials. The aim is to provide an understanding of the past research into optical cladding of sapphire fibers and to assess possible material systems for future research on this challenging problem for harsh environment sensors.

  16. Ionizing Radiation Detectors Based on Ge-Doped Optical Fibers Inserted in Resonant Cavities

    Directory of Open Access Journals (Sweden)

    Saverio Avino

    2015-02-01

    Full Text Available The measurement of ionizing radiation (IR is a crucial issue in different areas of interest, from environmental safety and industrial monitoring to aerospace and medicine. Optical fiber sensors have recently proven good candidates as radiation dosimeters. Here we investigate the effect of IR on germanosilicate optical fibers. A piece of Ge-doped fiber enclosed between two fiber Bragg gratings (FBGs is irradiated with gamma radiation generated by a 6 MV medical linear accelerator. With respect to other FBG-based IR dosimeters, here the sensor is only the bare fiber without any special internal structure. A near infrared laser is frequency locked to the cavity modes for high resolution measurement of radiation induced effects on the fiber optical parameters. In particular, we observe a variation of the fiber thermo-optic response with the radiation dose delivered, as expected from the interaction with Ge defect centers, and demonstrate a detection limit of 360 mGy. This method can have an impact in those contexts where low radiation doses have to be measured both in small volumes or over large areas, such as radiation therapy and radiation protection, while bare optical fibers are cheap and disposable.

  17. Distributed optical fiber-based monitoring approach of spatial seepage behavior in dike engineering

    Science.gov (United States)

    Su, Huaizhi; Ou, Bin; Yang, Lifu; Wen, Zhiping

    2018-07-01

    The failure caused by seepage is the most common one in dike engineering. As to the characteristics of seepage in dike, such as longitudinal extension engineering, the randomness, strong concealment and small initial quantity order, by means of distributed fiber temperature sensor system (DTS), adopting an improved optical fiber layer layout scheme, the location of initial interpolation point of the saturation line is obtained. With the barycentric Lagrange interpolation collocation method (BLICM), the infiltrated surface of dike full-section is generated. Combined with linear optical fiber monitoring seepage method, BLICM is applied in an engineering case, which shows that a real-time seepage monitoring technique is presented in full-section of dike based on the combination method.

  18. Gamma-Ray Dosimetry System Using Radiation-Resistant Optical Fibers and a Luminescent Material

    International Nuclear Information System (INIS)

    Toh, K.; Nakamura, T.; Yamagishi, H.; Sakasai, K.; Soyama, K.; Shikama, T.; Nagata, S.

    2013-06-01

    Gamma-ray dosimetry system using radiation-resistant optical fibers and a luminescent material was developed for use in a damaged Fukushima Dai-ichi nuclear power plant. The system was designed to be compact and unnecessary of an external supply of electricity to a radiation sensor head with a contaminated working environment and restricted through-holes to a measurement point in the damaged reactor. The system can detect a gamma-ray dose rate at a measurement point using a couple of optical fibers and a luminescent material with a coincidence method. This system demonstrated a linear response with respect to the gamma-ray dose rate from 0.5 mGy/h to 0.1 Gy/h and the system had a capability to measure the dose rate of more than 10 2 Gy/h. (authors)

  19. Modeling illumination performance of plastic optical fiber passive daylighting system

    Energy Technology Data Exchange (ETDEWEB)

    Sulaiman, F; Ahmad, A [Universiti Teknologi MARA, Shah Alam (Malaysia). Faculty of Electrical Engineering; Ahmed, A Z [Universiti Teknologi MARA, Shah Alam (Malaysia). Bureau of Reseaarch and Consultancy

    2006-12-15

    of the most direct methods of utilizing solar energy for energy conservation is to bring natural light indoors to light up an area. This paper reports on the investigation of the feasibility to utilize large core optical fibers to convey and distribute solar light passively throughout residential or commercial structures. The focus of this study is on the mathematical modeling of the illumination performance and the light transmission efficiency of solid core end light fiber for optical day lighting systems. The Meatball simulations features the optical fiber transmittance for glass and plastic fibers, illumination performance over lengths of plastic end-lit fiber, spectral transmission, light intensity loss through the large diameter solid core optical fibers as well as the transmission efficiency of the optical fiber itself. It was found that plastic optical fiber has less transmission loss over the distance of the fiber run which clearly shows that the Plastic Optical Fiber should be optimized for emitting visible light. The findings from the analysis on the performance of large diameter optical fibers for day lighting systems seems feasible for energy efficient lighting system in commercial or residential buildings.

  20. Modeling illumination performance of plastic optical fiber passive daylighting system

    International Nuclear Information System (INIS)

    Sulaiman, F.; Ahmad, A.; Ahmed, A.Z.

    2006-01-01

    One of the most direct methods of utilizing solar energy for energy conservation is to bring natural light indoors to light up an area. This paper reports on the investigation of the feasibility to utilize large core optical fibers to convey and distribute solar light passively throughout residential or commercial structures. The focus of this study is on the mathematical modeling of the illumination performance and the light transmission efficiency of solid core end light fiber for optical day lighting systems. The Meatball simulations features the optical fiber transmittance for glass and plastic fibers, illumination performance over lengths of plastic end-lit fiber, spectral transmission, light intensity loss through the large diameter solid core optical fibers as well as the transmission efficiency of the optical fiber itself. It was found that plastic optical fiber has less transmission loss over the distance of the fiber run which clearly shows that the Plastic Optical Fiber should be optimized for emitting visible light. The findings from the analysis on the performance of large diameter optical fibers for day lighting systems seems feasible for energy efficient lighting system in commercial or residential buildings

  1. Development of Optical Fiber Technology in Poland, International Journal of Electronics and Telecommunication, vol. 57, no 2, pp.191-197, July 2011

    CERN Document Server

    Dorosz, J

    2011-01-01

    In this paper, the authors, chairmen of the 13th Conference on Optical Fibers and Their Applications OFA2011, and editors of the conference proceedings summarize the development of optical fiber technology in Poland (during the period of 2009- 2011) on the basis of papers presented there and consecutively published in this volume. The digest is thus not full but covers the periodically presented material every 18 months during the meetings on optical fibers in Białystok-Białowie˙za and Lublin- Krasnobród. OFC systems are developed for HEP experiments and accelerators. OFC systems are also developed for virtual atomic clocks. EuCARD information presentation was organized during this meeting. Keywords— optical fibers, optical communication systems, photonic sources and detectors, photonic sensors, integrated optics, photonics applications, photonic materials.

  2. Microstructured Optical Fiber for X-ray Detection

    Science.gov (United States)

    DeHaven, Stanton L.

    2009-01-01

    A novel scintillating optical fiber is presented using a composite micro-structured quartz optical fiber. Scintillating materials are introduced into the multiple inclusions of the fiber. This creates a composite optical fiber having quartz as a cladding with an organic scintillating material core. X-ray detection using these fibers is compared to a collimated cadmium telluride (CdTe) detector over an energy range from 10 to 40 keV. Results show a good correlation between the fiber count rate trend and that of the CdTe detector.

  3. Security System Responsive to Optical Fiber Having Bragg Grating

    Science.gov (United States)

    Gary, Charles K. (Inventor); Ozcan, Meric (Inventor)

    1997-01-01

    An optically responsive electronic lock is disclosed comprising an optical fiber serving as a key and having Bragg gratings placed therein. Further, an identification system is disclosed which has the optical fiber serving as means for tagging and identifying an object. The key or tagged object is inserted into a respective receptacle and the Bragg gratings cause the optical fiber to reflect a predetermined frequency spectra pattern of incident light which is detected by a decoder and compared against a predetermined spectrum to determine if an electrical signal is generated to either operate the lock or light a display of an authentication panel.

  4. Fast modal decomposition for optical fibers using digital holography.

    Science.gov (United States)

    Lyu, Meng; Lin, Zhiquan; Li, Guowei; Situ, Guohai

    2017-07-26

    Eigenmode decomposition of the light field at the output end of optical fibers can provide fundamental insights into the nature of electromagnetic-wave propagation through the fibers. Here we present a fast and complete modal decomposition technique for step-index optical fibers. The proposed technique employs digital holography to measure the light field at the output end of the multimode optical fiber, and utilizes the modal orthonormal property of the basis modes to calculate the modal coefficients of each mode. Optical experiments were carried out to demonstrate the proposed decomposition technique, showing that this approach is fast, accurate and cost-effective.

  5. Constitutive Modeling of the Mechanical Properties of Optical Fibers

    Science.gov (United States)

    Moeti, L.; Moghazy, S.; Veazie, D.; Cuddihy, E.

    1998-01-01

    Micromechanical modeling of the composite mechanical properties of optical fibers was conducted. Good agreement was obtained between the values of Young's modulus obtained by micromechanics modeling and those determined experimentally for a single mode optical fiber where the wave guide and the jacket are physically coupled. The modeling was also attempted on a polarization-maintaining optical fiber (PANDA) where the wave guide and the jacket are physically decoupled, and found not to applicable since the modeling required perfect bonding at the interface. The modeling utilized constituent physical properties such as the Young's modulus, Poisson's ratio, and shear modulus to establish bounds on the macroscopic behavior of the fiber.

  6. Optical Fibers in Nuclear Reactor Radiation Environments.

    Science.gov (United States)

    Holcomb, David Eugene

    1992-01-01

    A performance evaluation of fiber optics under radiation conditions similar to those encountered in nuclear power plants is reported. The evaluation was accomplished by the creation of an analytical model for atomic scale radiation damage in silica glass and by the execution of an extensive fiber performance measurement program. The analytic model calculates displacement and electronic damage rates for silica glass subjected to a specified nuclear reactor radiation environment. It accomplishes this by first generating the primary charged particle spectrum produced in silica irradiated in a nuclear reactor. The resultant spectra are then applied to the integral equations describing radiation damage in polyatomic solids. The experimental measurements were selected to span the range of fiber types, radiation environments, temperatures, and light powers expected to be used in nuclear power plants. The basic experimental protocol was to expose the optical fibers to either a nuclear reactor or a ^{60}Co radiation environment while simultaneously monitoring fiber light transmission. Experimental temperatures were either ~23 ^circC or ~100 ^circC and light powers were either -30 dBm or -60 dBm. Measurements were made at each of the three standard communications wavelengths (850 nm, 1300 nm, and 1550 nm). Several conclusions are made based on these performance measurements. First, even near the core of a nuclear reactor the vast majority of the dose to silica glass is due to gamma rays. Even with the much lower doses (factor of roughly 40) neutrons cause much more displacement damage than gamma rays (35 times the oxygen displacement rate and 500 times the silicon displacement rate). Even with neutrons having many times the displacement rate as compared with gamma rays, little if any difference is observed in the transmission losses for gamma only as compared to mixed neutron/gamma transmission losses. Therefore, atomic displacement is not a significant damage mechanism for

  7. Tapered Optical Fiber Functionalized with Palladium Nanoparticles by Drop Casting and Laser Radiation for H₂ and Volatile Organic Compounds Sensing Purposes.

    Science.gov (United States)

    González-Sierra, Nancy Elizabeth; Gómez-Pavón, Luz Del Carmen; Pérez-Sánchez, Gerardo Francisco; Luis-Ramos, Arnulfo; Zaca-Morán, Plácido; Muñoz-Pacheco, Jesús Manuel; Chávez-Ramírez, Francisco

    2017-09-06

    A comparative study on the sensing properties of a tapered optical fiber pristine and functionalized with the palladium nanoparticles to hydrogen and volatile organic compounds (VOCs), is presented. The sensor response and, response/recovery times were extracted from the measurements of the transient response of the device. The tapered optical fiber sensor was fabricated using a single-mode optical fiber by the flame-brushing technique. Functionalization of the optical fiber was performed using an aqueous solution of palladium chloride by drop-casting technique assisted for laser radiation. The detection principle of the sensor is based on the changes in the optical properties of palladium nanoparticles when exposed to reducing gases, which causes a variation in the absorption of evanescent waves. A continuous wave laser diode operating at 1550 nm is used for the sensor characterization. The sensor functionalized with palladium nanoparticles by this technique is viable for the sensing of hydrogen and VOCs, since it shows an enhancement in sensor response and response time compared to the sensor based on the pristine optical microfiber. The results show that the fabricated sensor is competitive with other fiber optic sensors functionalized with palladium nanoparticles to the hydrogen.

  8. Optical Fiber Sensor with Distributed Parameters Based on Optical Fiber Reflectometry

    Directory of Open Access Journals (Sweden)

    Branislav Korenko

    2011-01-01

    Full Text Available His paper deals with the two-stage two-phase electronic systems with orthogonal output voltages and currents - DC/AC/AC. Design of two-stage DC/AC/AC high frequency converter with two-phase orthogonal output using single-phase matrix converter is also introduced. Output voltages of them are strongly nonharmonic ones, so they must be pulse-modulated due to requested nearly sinusoidal currents with low total harmonic distortion. Simulation experiment results of matrix converter for both steady and transient states for IM motors are given in the paper, also experimental verification under R-L load, so far. The simulation results confirm a very good time-waveform of the phase current and the system seems to be suitable for low-cost application in automotive/aerospace industries and application with high frequency voltage sources.

  9. Rayleigh scattering in few-mode optical fibers.

    Science.gov (United States)

    Wang, Zhen; Wu, Hao; Hu, Xiaolong; Zhao, Ningbo; Mo, Qi; Li, Guifang

    2016-10-24

    The extremely low loss of silica fibers has enabled the telecommunication revolution, but single-mode fiber-optic communication systems have been driven to their capacity limits. As a means to overcome this capacity crunch, space-division multiplexing (SDM) using few-mode fibers (FMF) has been proposed and demonstrated. In single-mode optical fibers, Rayleigh scattering serves as the dominant mechanism for optical loss. However, to date, the role of Rayleigh scattering in FMFs remains elusive. Here we establish and experimentally validate a general model for Rayleigh scattering in FMFs. Rayleigh backscattering not only sets the intrinsic loss limit for FMFs but also provides the theoretical foundation for few-mode optical time-domain reflectometry, which can be used to probe perturbation-induced mode-coupling dynamics in FMFs. We also show that forward inter-modal Rayleigh scattering ultimately sets a fundamental limit on inter-modal-crosstalk for FMFs. Therefore, this work not only has implications specifically for SDM systems but also broadly for few-mode fiber optics and its applications in amplifiers, lasers, and sensors in which inter-modal crosstalk imposes a fundamental performance limitation.

  10. Mach-Zehnder atom interferometer inside an optical fiber

    Science.gov (United States)

    Xin, Mingjie; Leong, Wuiseng; Chen, Zilong; Lan, Shau-Yu

    2017-04-01

    Precision measurement with light-pulse grating atom interferometry in free space have been used in the study of fundamental physics and applications in inertial sensing. Recent development of photonic band-gap fibers allows light for traveling in hollow region while preserving its fundamental Gaussian mode. The fibers could provide a very promising platform to transfer cold atoms. Optically guided matter waves inside a hollow-core photonic band-gap fiber can mitigate diffraction limit problem and has the potential to bring research in the field of atomic sensing and precision measurement to the next level of compactness and accuracy. Here, we will show our experimental progress towards an atom interferometer in optical fibers. We designed an atom trapping scheme inside a hollow-core photonic band-gap fiber to create an optical guided matter waves system, and studied the coherence properties of Rubidium atoms in this optical guided system. We also demonstrate a Mach-Zehnder atom interferometer in the optical waveguide. This interferometer is promising for precision measurements and designs of mobile atomic sensors.

  11. Optical fiber Cherenkov detector for beam current monitoring

    International Nuclear Information System (INIS)

    Pishchulin, I.V.; Solov'ev, N.G.; Romashkin, O.B.

    1991-01-01

    The results obtained in calculation of an optical fiber Cherenkov detector for accelerated beam current monitoring are presented. The technique of beam parameters monitoring is based on Cherenkov radiation excitation by accelerated electrons in the optical fiber. The formulas for calculations of optical power and time dependence of Cherenkov radiation pulse are given. The detector sensitivity and time resolution dependence on the fiber material characteristics are investigated. Parameters of a 10μm one-mode quartz optical fiber detector for the free electron laser photoinjector are calculated. The structure of a monitoring system with the optical fiber Cherenkov detector is considered. Possible applications of this technique are discussed and some recommendations are given

  12. Radiation distribution sensing with normal optical fiber

    CERN Document Server

    Kawarabayashi, J; Naka, R; Uritani, A; Watanabe, K I; Iguchi, T; Tsujimura, N

    2002-01-01

    The purpose of this study is to develop a radiation distribution monitor using a normal plastic optical fiber. The monitor has a long operating length (10m-100m) and can obtain continuous radiation distributions. A principle of the position sensing is based on a time-of-flight technique. The characteristics of this monitor to beta particles, gamma rays and fast neutrons were obtained. The spatial resolutions for beta particles ( sup 9 sup 0 Sr sup - sup 9 sup 0 Y), gamma rays ( sup 1 sup 3 sup 7 Cs) and D-T neutrons were 30 cm, 37 cm and 13 cm, respectively. The detection efficiencies for the beta rays, the gamma rays and D-T neutrons were 0.11%, 1.6x10 sup - sup 5 % and 5.4x10 sup - sup 4 %, respectively. The effective attenuation length of the detection efficiency was 18m. New principle of the position sensing based on spectroscopic analysis was also proposed. A preliminary test showed that the spectrum observed at the end of the fiber depended on the position of the irradiated point. This fact shows that t...

  13. Radiation distribution sensing with normal optical fiber

    Energy Technology Data Exchange (ETDEWEB)

    Kawarabayashi, Jun; Mizuno, Ryoji; Naka, Ryotaro; Uritani, Akira; Watanabe, Ken-ichi; Iguchi, Tetsuo [Nagoya Univ., Dept. of Nuclear Engineering, Nagoya, Aichi (Japan); Tsujimura, Norio [Japan Nuclear Cycle Development Inst., Tokai Works, Tokai, Ibaraki (Japan)

    2002-12-01

    The purpose of this study is to develop a radiation distribution monitor using a normal plastic optical fiber. The monitor has a long operating length (10m-100m) and can obtain continuous radiation distributions. A principle of the position sensing is based on a time-of-flight technique. The characteristics of this monitor to beta particles, gamma rays and fast neutrons were obtained. The spatial resolutions for beta particles ({sup 90}Sr{sup -90}Y), gamma rays ({sup 137}Cs) and D-T neutrons were 30 cm, 37 cm and 13 cm, respectively. The detection efficiencies for the beta rays, the gamma rays and D-T neutrons were 0.11%, 1.6x10{sup -5}% and 5.4x10{sup -4}%, respectively. The effective attenuation length of the detection efficiency was 18m. New principle of the position sensing based on spectroscopic analysis was also proposed. A preliminary test showed that the spectrum observed at the end of the fiber depended on the position of the irradiated point. This fact shows that the radiation distributions were calculated from the spectrum by mathematical deconvolution technique. (author)

  14. Radiation distribution sensing with normal optical fiber

    International Nuclear Information System (INIS)

    Kawarabayashi, Jun; Mizuno, Ryoji; Naka, Ryotaro; Uritani, Akira; Watanabe, Ken-ichi; Iguchi, Tetsuo; Tsujimura, Norio

    2002-01-01

    The purpose of this study is to develop a radiation distribution monitor using a normal plastic optical fiber. The monitor has a long operating length (10m-100m) and can obtain continuous radiation distributions. A principle of the position sensing is based on a time-of-flight technique. The characteristics of this monitor to beta particles, gamma rays and fast neutrons were obtained. The spatial resolutions for beta particles ( 90 Sr -90 Y), gamma rays ( 137 Cs) and D-T neutrons were 30 cm, 37 cm and 13 cm, respectively. The detection efficiencies for the beta rays, the gamma rays and D-T neutrons were 0.11%, 1.6x10 -5 % and 5.4x10 -4 %, respectively. The effective attenuation length of the detection efficiency was 18m. New principle of the position sensing based on spectroscopic analysis was also proposed. A preliminary test showed that the spectrum observed at the end of the fiber depended on the position of the irradiated point. This fact shows that the radiation distributions were calculated from the spectrum by mathematical deconvolution technique. (author)

  15. IMPACT STUDY OF ANISOTROPIC OPTICAL FIBERS WINDING WITH DIFFERENT TENSION VALUE ON THE H-PARAMETER INVARIANCE DEGREE

    Directory of Open Access Journals (Sweden)

    A. B. Mukhtubayev

    2015-09-01

    Full Text Available Subject of Research. We have investigated the effect of anisotropic optical fibers winding with an elliptical sheath subjecting to stress on the H-parameter invariance degree. This type of optical fiber is used in the manufacture of fiber loop in fiber-optic gyroscopes. Method of Research. The method of research is based on the application of Michelson polarization scanning interferometer as a measuring device. Superluminescent diode with a central wavelength of 1575 nm and a half-width of the spectrum equal to 45 nm is used as a radiation source. The studies were carried out with anisotropic optical fiber with 50 m long elliptical sheath subjecting to stress. The fiber was wound with one layer turn to turn on the coil with a diameter of 18 cm, which is used in the design of fiber-optic gyroscope. The tension force of the optical fiber was controlled during winding on a special machine. Main Results. It was found that at the increase of tension force from 0.05 N to 0.8 H the value of H-parameter increases from 7×10-6 1/m up to 178×10-6 1/m, respectively; i.e. the coupling coefficient of orthogonal modes in the test fiber is being increased. Thus, it is necessary to consider the longitudinal tension force of fiber in the design and manufacture of the fiber-optic sensors of high accuracy class: the less the fiber winding power, the higher invariance degree of distributed H-parameter. The longitudinal tension force of anisotropic optical fiber with elliptical sheath subjecting to stress equal to 0.2 N is recommended in the process of designing fiber-optic gyroscopes. Practical Relevance. The proposed method of Michelson scanning interferometer is usable in the production process for quality determination of the optical fiber winding: no local defects, value controlling of fiber H-parameter.

  16. The Influence of Motion and Stress on Optical Fibers

    OpenAIRE

    Murphy, Jeremy D.; Hill, Gary J.; MacQueen, Phillip J.; Taylor, Trey; Soukup, Ian; Moreira, Walter; Cornell, Mark E.; Good, John; Anderson, Seth; Fuller, Lindsay; Lee, Hanshin; Kelz, Andreas; Rafal, Marc; Rafferty, Tom; Tuttle, Sarah

    2013-01-01

    We report on extensive testing carried out on the optical fibers for the VIRUS instrument. The primary result of this work explores how 10+ years of simulated wear on a VIRUS fiber bundle affects both transmission and focal ratio degradation (FRD) of the optical fibers. During the accelerated lifetime tests we continuously monitored the fibers for signs of FRD. We find that transient FRD events were common during the portions of the tests when motion was at telescope slew rates, but dropped t...

  17. Effects of Temperature and X-rays on Plastic Scintillating Fiber and Infrared Optical Fiber.

    Science.gov (United States)

    Lee, Bongsoo; Shin, Sang Hun; Jang, Kyoung Won; Yoo, Wook Jae

    2015-05-11

    In this study, we have studied the effects of temperature and X-ray energy variations on the light output signals from two different fiber-optic sensors, a fiber-optic dosimeter (FOD) based on a BCF-12 as a plastic scintillating fiber (PSF) and a fiber-optic thermometer (FOT) using a silver halide optical fiber as an infrared optical fiber (IR fiber). During X-ray beam irradiation, the scintillating light and IR signals were measured simultaneously using a dosimeter probe of the FOD and a thermometer probe of the FOT. The probes were placed in a beaker with water on the center of a hotplate, under variation of the tube potential of a digital radiography system or the temperature of the water in the beaker. From the experimental results, in the case of the PSF, the scintillator light output at the given tube potential decreased as the temperature increased in the temperature range from 25 to 60 °C. We demonstrated that commonly used BCF-12 has a significant temperature dependence of -0.263 ± 0.028%/°C in the clinical temperature range. Next, in the case of the IR fiber, the intensity of the IR signal was almost uniform at each temperature regardless of the tube potential range from 50 to 150 kVp. Therefore, we also demonstrated that the X-ray beam with an energy range used in diagnostic radiology does not affect the IR signals transmitted via a silver halide optical fiber.

  18. Micro-vision servo control of a multi-axis alignment system for optical fiber assembly

    International Nuclear Information System (INIS)

    Chen, Weihai; Yu, Fei; Qu, Jianliang; Chen, Wenjie; Zhang, Jianbin

    2017-01-01

    This paper describes a novel optical fiber assembly system featuring a multi-axis alignment function based on micro-vision feedback control. It consists of an active parallel alignment mechanism, a passive compensation mechanism, a micro-gripper and a micro-vision servo control system. The active parallel alignment part is a parallelogram-based design with remote-center-of-motion (RCM) function to achieve precise rotation without fatal lateral motion. The passive mechanism, with five degrees of freedom (5-DOF), is used to implement passive compensation for multi-axis errors. A specially designed 1-DOF micro-gripper mounted onto the active parallel alignment platform is adopted to grasp and rotate the optical fiber. A micro-vision system equipped with two charge-coupled device (CCD) cameras is introduced to observe the small field of view and obtain multi-axis errors for servo feedback control. The two CCD cameras are installed in an orthogonal arrangement—thus the errors can be easily measured via the captured images. Meanwhile, a series of tracking and measurement algorithms based on specific features of the target objects are developed. Details of the force and displacement sensor information acquisition in the assembly experiment are also provided. An experiment demonstrates the validity of the proposed visual algorithm by achieving the task of eliminating errors and inserting an optical fiber to the U-groove accurately. (paper)

  19. Rancang Buat Sensor Kekeruhan Air Berbasis Serat Optik Plastik

    OpenAIRE

    Irwan, Indawani

    2017-01-01

    It has been the research concerning about turbidity sensor based on plastic optical fiber is used to measure degree of turbidity water. Turbidity sensor based on plastic optical fiber have two types, there are optical fiber sensor with cladding and without cladding. This sensor was made with different types of lenghts and configuration. Turbidity sensor was made, dippeded into a turbidity water samples. The results showed us that output voltage is not comprabel with turbidity sample concentra...

  20. Laser backlight unit based on a leaky optical fiber

    Science.gov (United States)

    Okuda, Yuuto; Onoda, Kousuke; Fujieda, Ichiro

    2012-07-01

    A backlight unit is constructed by laying out an optical fiber on a two-dimensional plane and letting the light leak out in a controlled manner. In experiment, we formed multiple grooves on the surface of a plastic optical fiber by pressing a heated knife edge. The depth of the groove determined the percentage of the optical power leaking out. The optical fiber with multiple grooves was embedded in an acrylic plate with a spiral trench, and a diffuser sheet was placed over it. When we injected laser light into the end of the optical fiber, this configuration successfully worked as an area illuminator. However, the coherent nature of the laser light caused severe speckle noise. We evaluated the speckle contrast under darkness, and it varied from 80% to 23%, depending on the lens aperture used to capture the images of the illuminator. We glued an ultrasound generator to the optical fiber to introduce phase modulation for the light propagating inside the optical fiber. In this way, the speckle contrast was reduced by a factor of seven to four. Under room lighting, the speckle noise was made barely noticeable by turning on the ultrasound generator.

  1. Germanium-doped optical fiber for real-time radiation dosimetry

    International Nuclear Information System (INIS)

    Mizanur Rahman, A.K.M.; Zubair, H.T.; Begum, Mahfuza; Abdul-Rashid, H.A.; Yusoff, Z.; Ung, N.M.; Mat-Sharif, K.A.; Wan Abdullah, W.S.; Amouzad Mahdiraji, Ghafour; Amin, Y.M.; Maah, M.J.; Bradley, D.A.

    2015-01-01

    Over the past three decades growing demand for individualized in vivo dosimetry and subsequent dose verification has led to the pursuit of newer, novel and economically feasible materials for dosimeters. These materials are to facilitate features such as real-time sensing and fast readouts. In this paper, purposely composed SiO 2 :Ge optical fiber is presented as a suitable candidate for dosimetry. The optical fiber is meant to take advantage of the RL/OSL technique, providing both online remote monitoring of dose rate, and fast readouts for absorbed dose. A laboratory-assembled OSL reader has been used to acquire the RL/OSL response to LINAC irradiations (6 MV photons). The notable RL characteristics observed include constant level of luminescence for the same dose rate (providing better consistency compared to TLD-500), and linearity of response in the radiotherapy range (1 Gy/min to 6 Gy/min). The OSL curve was found to conform to an exponential decay characteristic (illumination with low LED source). The Ge doping resulted in an effective atomic number, Z eff , of 13.5 (within the bone equivalent range). The SiO 2 :Ge optical fiber sensor, with efficient coupling, can be a viable solution for in vivo dosimetry, besides a broad range of applications. - Highlights: • Purposely fabricated Ge doped silica fiber for real-time dose measurements. • Constant RL response for dose rates in radiotherapy range. • Linearity of RL curve during irradiation using LINAC. • RL response comparison between SiO 2 :Ge optical fiber and TLD-500.

  2. Construction of bent functions from near-bent functions

    DEFF Research Database (Denmark)

    Leander, Gregor; McGuire, G.

    2009-01-01

    We give a construction of bent functions in dimension 2m from near-bent functions in dimension 2m - 1. in particular, we give the first ever examples of non-weakly-normal bent functions in dimensions 10 and 12, which demonstrates the significance of our construction....

  3. Low Loss Polycarbonate Polymer Optical Fiber for High Temperature FBG Humidity Sensing

    DEFF Research Database (Denmark)

    Woyessa, Getinet; Fasano, Andrea; Markos, Christos

    2017-01-01

    We report the fabrication and characterization of a polycarbonate (PC) microstructured polymer optical fiber (mPOF) Bragg grating (FBG) humidity sensor that can operate beyond 100°C. The PC preform, from which the fiber was drawn, was produced using an improved casting approach to reduce...... the attenuation of the fiber. The fiber loss was found reduced by a factor of two compared to the latest reported PC mPOF [20], holding the low loss record in PC based fibers. PC mPOFBG was characterized to humidity and temperature, and a relative humidity (RH) sensitivity of 7.31± 0.13 pm/% RH in the range 10...

  4. Applications of plastic optical fiber in communication

    Science.gov (United States)

    Tayahi, Moncef Ben

    In this thesis, we report the results of our theoretical and experimental studies of large core polymer fibers. This relatively low loss and high bandwidth plastic optical fiber (POF) potentially have important applications in LAN. We measured the power penalty due to modal noise. We also developed a model to calculate the signal to noise ratio (SNR) and the bit error rate (BER) floor just by knowing the coupling coefficient in the mode selective loss being considered. The calculated bandwidth using the WKB approximation was found to be 0.44 GHz per 100 m, which is much lower than the measured bandwidth of 3 GHz per 100 m. This discrepancy was explained by the presence of strong mode coupling in POFs. We studied distortions products in CATV systems. Composite second order (CSO) and composite triple beat (CTB) for different channels were measured using a spectrum analyzer and adjustable band pass filter. Since the CSO and the CTB did not meet the CATV standard, a predistortion circuit was used to minimize CSO and CTB products produced by the laser. The predistortion circuit provides a signal comprising multiple subcarrier signals substantially equal in magnitude and opposite in phase to those associated with the nonlinear transfer function of the laser being deployed. The RF signal is split into a primary branch that has a time delayed portion (80% of the RF signal), the secondary branch (10% of the RF signal) is where the second order products are generated with a 180 °phase shift from the fundamental, and the last remaining 10% of the RF signal is where the third order distortion products are generated with a 180 °phase shift from the fundamental. The output signal is taken as the summation of three signals processed by the branch circuits and coupled to the directly to the laser to be linearized. Finally, using cyclic transparent optical polymer (CYTOP), a perfluorinated graded index fiber, different transmission characteristics were investigated. CYTOP fiber

  5. Photonic jet etching: Justifying the shape of optical fiber tip

    Science.gov (United States)

    Abdurrochman, Andri; Zelgowski, Julien; Lecler, Sylvain; Mermet, Frédéric; Tumbelaka, Bernard; Fontaine, Joël

    2016-02-01

    Photonic jet (PJ) is a low diverging and highly concentrated beam in the shadow side of dielectric particle (cylinder or sphere). The concentration can be more than 200 times higher than the incidence wave. It is a non-resonance phenomenon in the near-field can propagate in a few wavelengths. Many potential applications have been proposed, including PJ etching. Hence, a guided-beam is considered increasing the PJ mobility control. While the others used a combination of classical optical fibers and spheres, we are concerned on a classical optical fiber with spherical tip to generate the PJ. This PJ driven waveguide has been realized using Gaussian mode beam inside the core. It has different variable parameters compared to classical PJ, which will be discussed in correlation with the etching demonstrations. The parameters dependency between the tip and PJ properties are complex; and theoretical aspect of this interaction will be exposed to justify the shape of our tip and optical fiber used in our demonstrations. Methods to achieve such a needed optical fiber tip will also be described. Finally the ability to generate PJ out of the shaped optical fiber will be experimentally demonstrated and the potential applications for material processing will be exposed.

  6. A Molecularly Imprinted Polymer on a Plasmonic Plastic Optical Fiber to Detect Perfluorinated Compounds in Water

    Directory of Open Access Journals (Sweden)

    Nunzio Cennamo

    2018-06-01

    Full Text Available A novel Molecularly Imprinted Polymer (MIP able to bind perfluorinated compounds, combined with a surface plasmon resonance (SPR optical fiber platform, is presented. The new MIP receptor has been deposited on a D-shaped plastic optical fiber (POF covered with a photoresist buffer layer and a thin gold film. The experimental results have shown that the developed SPR-POF-MIP sensor makes it possible to selectively detect the above compounds. In this work, we present the results obtained with perfluorooctanoate (PFOA compound, and they hold true when obtained with a perfluorinated alkylated substances (PFAs mixture sample. The sensor’s response is the same for PFOA, perfluorooctanesulfonate (PFOS or PFA contaminants in the C4–C11 range. We have also tested a sensor based on a non-imprinted polymer (NIP on the same SPR in a D-shaped POF platform. The limit of detection (LOD of the developed chemical sensor was 0.13 ppb. It is similar to the one obtained by the configuration based on a specific antibody for PFOA/PFOS exploiting the same SPR-POF platform, already reported in literature. The advantage of an MIP receptor is that it presents a better stability out of the native environment, very good reproducibility, low cost and, furthermore, it can be directly deposited on the gold layer, without modifying the metal surface by functionalizing procedures.

  7. Enhancement of accuracy in shape sensing of surgical needles using optical frequency domain reflectometry in optical fibers.

    Science.gov (United States)

    Parent, Francois; Loranger, Sebastien; Mandal, Koushik Kanti; Iezzi, Victor Lambin; Lapointe, Jerome; Boisvert, Jean-Sébastien; Baiad, Mohamed Diaa; Kadoury, Samuel; Kashyap, Raman

    2017-04-01

    We demonstrate a novel approach to enhance the precision of surgical needle shape tracking based on distributed strain sensing using optical frequency domain reflectometry (OFDR). The precision enhancement is provided by using optical fibers with high scattering properties. Shape tracking of surgical tools using strain sensing properties of optical fibers has seen increased attention in recent years. Most of the investigations made in this field use fiber Bragg gratings (FBG), which can be used as discrete or quasi-distributed strain sensors. By using a truly distributed sensing approach (OFDR), preliminary results show that the attainable accuracy is comparable to accuracies reported in the literature using FBG sensors for tracking applications (~1mm). We propose a technique that enhanced our accuracy by 47% using UV exposed fibers, which have higher light scattering compared to un-exposed standard single mode fibers. Improving the experimental setup will enhance the accuracy provided by shape tracking using OFDR and will contribute significantly to clinical applications.

  8. Integration of optical fibers in radiative environments: Advantages and limitations

    International Nuclear Information System (INIS)

    Girard, S.; Ouerdane, Y.; Boukenter, A.; Marcandella, C.; Bisutti, J.; Baggio, J.; Meunier, J. P.

    2011-01-01

    We review the advantages and limitations for the integration of optical fibers in radiative environments. Optical fibers present numerous advantages for applications in harsh environments such as their electromagnetic immunity. This explains the increasing interest of the radiation effects community to evaluate their vulnerability for future facilities. However, it is also well-known that optical fibers suffer from a degradation of their macroscopic properties under irradiation. We illustrate the major mechanisms and parameters that govern the degradation mechanism, mainly the radiation-induced attenuation phenomena. We focus on the fiber transient radiation responses when exposed to the pulsed and mixed environment associated with the Megajoule class lasers devoted to the fusion by inertial confinement study. (authors)

  9. Photothermal lesions in soft tissue induced by optical fiber microheaters.

    Science.gov (United States)

    Pimentel-Domínguez, Reinher; Moreno-Álvarez, Paola; Hautefeuille, Mathieu; Chavarría, Anahí; Hernández-Cordero, Juan

    2016-04-01

    Photothermal therapy has shown to be a promising technique for local treatment of tumors. However, the main challenge for this technique is the availability of localized heat sources to minimize thermal damage in the surrounding healthy tissue. In this work, we demonstrate the use of optical fiber microheaters for inducing thermal lesions in soft tissue. The proposed devices incorporate carbon nanotubes or gold nanolayers on the tips of optical fibers for enhanced photothermal effects and heating of ex vivo biological tissues. We report preliminary results of small size photothermal lesions induced on mice liver tissues. The morphology of the resulting lesions shows that optical fiber microheaters may render useful for delivering highly localized heat for photothermal therapy.

  10. Effect of ionizing radiation on in situ Raman scattering and photoluminescence of silica optical fibers

    International Nuclear Information System (INIS)

    Bilodeau, T.G.; Ewing, K.J.; Nau, G.M.; Aggarwal, I.D.

    1995-01-01

    Raman fiber optic chemical sensors provide remote situ characterization capability. One application of Raman fiber optic chemical sensors is the characterization of the contents of nuclear waste tanks. In these tanks it is expected that approximately 20 meters of optical fiber will be exposed to radiation levels between 100 and 1,000 rads/hour. In support of this work two silica optical fiber types (one a communications grade fiber and the other nominally radiation resistant) have been tested at the radiation levels expected in the tanks. Luminescence and Raman scattering measurements have been performed in situ with 488-nm excitation on two types of silica optical fiber exposed to a constant low to moderate dose rate of gamma radiation of 880 rads(Si)/hour from a 60 Co source for a total dose of greater than 45 krads. The nominally radiation-resistant fiber was also excited with 514.5-nm and near-infrared 830-nm laser radiation. The rate of the silica Raman signal decrease is more than three times greater for the visible excitation wavelengths than for the 830-nm excitation for the radiation resistant fiber. The behavior of the 650-nm photoluminescence line upon irradiation was different for the two fibers studied, both in terms of the shift of the 650-nm line and rate of increase of the normalized photoluminescence intensity. In all cases the photoluminescence from the fibers was less than the Raman intensity. No radioluminescence was observed in either fiber. The radiation resistant fiber exhibited photo bleaching effects on the Raman transmission when photoannealed with 488-nm laser light

  11. Effect of ionizing radiation on in situ Raman scattering and photoluminescence of silica optical fibers

    Science.gov (United States)

    Bilodeau, T. G.; Ewing, K. J.; Nau, G. M.; Aggarwai, I. D.

    1995-02-01

    Raman fiber optic chemical sensors provide remote in situ characterization capability. One application of Raman fiber optic chemical sensors is the characterization of the contents of nuclear waste tanks. In these tanks it is expected that approximately 20 meters of optical fiber will be exposed to radiation levels between 100 and 1000 rads/hour. In support of this work two silica optical fiber types (one a communications grade fiber and the other nominally radiation resistant) have been tested at the radiation levels expected in the tanks. Luminescence and Raman scattering measurements have been performed in situ with 488-nm excitation on two types of silica optical fiber exposed to a constant low to moderate dose rate of gamma radiation of 880 rads(Si)/hour from a /sup 60/Co source for a total dose of greater than 45 krads. The nominally radiation-resistant fiber was also excited with 514.5-nm and near-infrared 830-nm laser radiation. The rate of the silica Raman signal decrease is more than three times greater for the visible excitation wavelengths than for the 830-nm excitation for the radiation resistant fiber. The behavior of the 650-nm photoluminescence line upon irradiation was different for the two fibers studied, both in terms of the shift of the 650-nm line and rate of increase of the normalized photoluminescence intensity. In all cases the photoluminescence from the fibers was less than the Raman intensity. No radioluminescence was observed in either fiber. The radiation resistant fiber exhibited photobleaching effects on the Raman transmission when photoannealed with 488-nm laser light.

  12. Three dimensional phase imaging using a scanning optical fiber interferometer

    International Nuclear Information System (INIS)

    Walford, J.N.; Nugent, K.A.; Roberts, A.; Scholten, R.E.

    1998-01-01

    A quantitative method for measuring phase in three dimensions using a scanning optical fiber interferometer is described. By exploiting phase modulation in the reference arm, this technique is insensitive to large variations in the intensity of the field being studied, and is therefore highly suitable for measurement of phase within spatially confined optical beams. It uses only a single detector, and is not reliant on lock-in electronics. The technique is applied to the measurement of the near field of a cleaved optical fiber and shown to produce results in good agreement with theory. (authors)

  13. Scintillating optical fibers for fine-grained hodoscopes

    International Nuclear Information System (INIS)

    Borenstein, S.R.; Strand, R.C.

    1981-01-01

    Fast detectors with fine spatial resolution will be needed to exploit high event rates at ISABELLE. Scintillating optical fibers for fine grained hodoscopes have been developed by the authors. A commercial manufacturer of optical fibers has drawn and clad PVT scintillator. Detection efficiencies greater than 99% have been achieved for a 1 mm fiber with a PMT over lengths up to 60 cm. Small diameter PMT's and avalanche photodiodes have been tested with the fibers. Further improvements are sought for the fiber and for the APD's sensitivity and coupling efficiency with the fiber

  14. Two mode optical fiber in space optics communication

    Science.gov (United States)

    Hampl, Martin

    2017-11-01

    In our contribution we propose to use of a two-mode optical fiber as a primary source in a transmitting optical head instead of the laser diode. The distribution of the optical intensity and the complex degree of the coherence on the output aperture of the lens that is irradiated by a step-index weakly guiding optical fiber is investigated. In our treatment we take into account weakly guided modes with polarization corrections to the propagation constant and unified theory of second order coherence and polarization of electromagnetic beams.

  15. The strength and failure of silica optical fibers

    International Nuclear Information System (INIS)

    Yan, C; Bai, R X; Yu, H; Canning, J; Law, S

    2010-01-01

    The mechanical strength and failure behavior of conventional and microstructured silica optical fibers was investigated using a tensile test and fracture mechanics and numerical analyses. The effect of polymer coating on failure behavior was also studied. The results indicate that all these fibers fail in a brittle manner and failure normally starts from fiber surfaces. The failure loads observed in coated fibers are higher than those in bare fibers. The introduction of air holes reduces fiber strength and their geometrical arrangements have a remarkable effect on stress distribution in the longitudinal direction. These results are potentially useful for the design, fabrication and evaluation of optical fibers for a wide range of applications.

  16. Quantum Dots Microstructured Optical Fiber for X-Ray Detection

    Science.gov (United States)

    DeHaven, Stan; Williams, Phillip; Burke, Eric

    2015-01-01

    Microstructured optical fibers containing quantum dots scintillation material comprised of zinc sulfide nanocrystals doped with magnesium sulfide are presented. These quantum dots are applied inside the microstructured optical fibers using capillary action. The x-ray photon counts of these fibers are compared to the output of a collimated CdTe solid state detector over an energy range from 10 to 40 keV. The results of the fiber light output and associated effects of an acrylate coating and the quantum dot application technique are discussed.

  17. Detection system using scintillating optical fibers and image tube readout

    International Nuclear Information System (INIS)

    Alspector, J.; Borenstein, S.

    1979-01-01

    The hodoscope subgroup has studied a detection system consisting of bundles of optical fibers with readout via image tubes. The basic building block is an optical fiber with a scintillator inner core. The inner core has refractive index n/sub o/ (1.58 for plastic scintillator), and the outer sheath has a low index (approx. 1.4). Light is created in the core by passage of a particle track; if the light strikes the sheath at an angle greater than the critical angle phi/sub c/, it is trapped in the fiber until it finds its way to the photon detector

  18. Spectrophotometry with optical fibers applied to nuclear product processing

    International Nuclear Information System (INIS)

    Boisde, G.; Perez, J.J.; Velluet, M.T.; Jeunhomme, L.B.

    1988-01-01

    Absorption spectrophotometry is widely used in laboratories for composition analysis and quality control of chemical processes. Using optical fibers for transmitting the light between the instrument and the process line allows to improve the safety and productivity of chemical processes, thanks to real time measurements. Such applications have been developed since 1975 in CEA for the monitoring of nuclear products. This has led to the development of fibers, measurement cells, and optical feedthrough sustaining high radiation doses, of fiber/spectrophotometer couplers, and finally of a photodiode array spectrophotometer optimized for being used together with optical fibers [fr

  19. Monitoring techniques for the manufacture of tapered optical fibers.

    Science.gov (United States)

    Mullaney, Kevin; Correia, Ricardo; Staines, Stephen E; James, Stephen W; Tatam, Ralph P

    2015-10-01

    The use of a range of optical techniques to monitor the process of fabricating optical fiber tapers is investigated. Thermal imaging was used to optimize the alignment of the optical system; the transmission spectrum of the fiber was monitored to confirm that the tapers had the required optical properties and the strain induced in the fiber during tapering was monitored using in-line optical fiber Bragg gratings. Tapers were fabricated with diameters down to 5 μm and with waist lengths of 20 mm using single-mode SMF-28 fiber.

  20. Development of optical fiber cable's inspection technology and maintenance criteria

    International Nuclear Information System (INIS)

    Kim, Min-Su; Ju, Hee-Wan; Shim, Seon-Heum; Lee, Youn-Ki; Kim, Jin-Il; Huh, Tae-Young

    2008-01-01

    Improve the reliability and establish the systematic maintenance methods for the digital control facilities' optical fiber cable, reviewed the technical requirements and the current maintenance procedures, analyzed the optical fiber cable's characteristics through actual test like bending, tension, attenuation. Based on the results of review, test and analysis, prepared the maintenance criteria and standard maintenance guideline. Also we verified those can be applied directly to the operating nuclear power plant through the actual test at Ulchin Unit 6. The details of test and analysis are presented in this paper. Also introduce the contents of maintenance criteria and guidelines