{"title":"Large-area fiber optic chemical sensors","authors":"M. Bliss, R. A. Craig","doi":"10.1117/12.207767","DOIUrl":"https://doi.org/10.1117/12.207767","url":null,"abstract":"Pacific Northwest Laboratory is developing a large-area chemical sensor that combines chemically coatings and optical spectroscopy to detect target compounds. The chemically selective material is incorporated into the cladding of an optical fiber waveguide. The material is interrogated using optical spectroscopic techniques to determine the concentration of target compounds. The optical interrogation method includes two spectroscopies: visible-near infrared absorption spectroscopy and Raman spectroscopy. This work develops the physical and mathematical models of such a sensor and provides a set of tools with which to make design predictions for the large-area chemical sensors. The theoretical relationships derived herein allow the use of bulk absorption parameters and bulk Raman coefficients to predict sensor performance.","PeriodicalId":293004,"journal":{"name":"Pacific Northwest Fiber Optic Sensor","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131347644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Chandrasekar, T. Radha, Boilahalli S. Ramprasad
{"title":"Simple fiber optic vibration sensor","authors":"B. Chandrasekar, T. Radha, Boilahalli S. Ramprasad","doi":"10.1117/12.207758","DOIUrl":"https://doi.org/10.1117/12.207758","url":null,"abstract":"A simple extrinsic fiber optic vibration sensor (FOVS) is described. Measurements are in the range of a maximum amplitude of 25 mm with frequencies up to 1 kHz. Evaluation of the natural frequencies and the damping coefficient are also demonstrated.","PeriodicalId":293004,"journal":{"name":"Pacific Northwest Fiber Optic Sensor","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131740999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Pseudo-depolarizer for interferometric fiber sensor applications","authors":"W. Jin, G. Stewart, K. Crawford, B. Culshaw","doi":"10.1117/12.207757","DOIUrl":"https://doi.org/10.1117/12.207757","url":null,"abstract":"In fiber optic interferometric sensors, polarization noise and fading may occur due to environmental induced birefringence fluctuations. One way to overcome this problem is to depolarize the source light. For broadband sources such as light emitting diodes, the light can be easily depolarized by utilizing fiber implementations of conventional Lyot depolarizes. However, for highly coherent lasers, this approach is not viable. Several techniques for producing a depolarized source from coherent light have been demonstrated. However, they are only suitable for certain input polarization states, and often involve bulk optical components which may not be ideal for certain applications. In this paper, we report a simple all fiber depolarizer for coherent light which is suitable for any input polarization states.","PeriodicalId":293004,"journal":{"name":"Pacific Northwest Fiber Optic Sensor","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132366274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fiber optic sensor for characterization of surface coatings","authors":"E. Franke","doi":"10.1117/12.207752","DOIUrl":"https://doi.org/10.1117/12.207752","url":null,"abstract":"A fiber optic sensor for determining the type and condition of aircraft coatings was originally developed to provide adaptive control of automated coating removal. The sensor, based on analysis of optical reflectance spectra, has also been found useful for determining the condition of other materials. Investigations have shown that artificial neural networks can be trained to recognize specific materials or material conditions from the sensor signals.","PeriodicalId":293004,"journal":{"name":"Pacific Northwest Fiber Optic Sensor","volume":"319 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122436028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Solubility properties of siloxane polymers for chemical sensors","authors":"J. Grate, M. Abraham","doi":"10.1117/12.207746","DOIUrl":"https://doi.org/10.1117/12.207746","url":null,"abstract":"Many chemical sensors rely on a sorbent material to collect and concentrate analyte molecules at the sensor's surface where they can be detected. Ideally, this sorbent material will impart the chemical sensor with both sensitivity and selectivity for the target species. If the sensor is to be reversible, then the species must also desorb from the material or be actively removed by some process such as catalytic destruction. Polymer materials offer many attractive features for chemical sensing. Organic compounds are readily sorbed in a reversible fashion, selectivity can be altered by varying the chemical structure, and polymer materials can be processed into thin films. In this paper, we discuss the factors that govern the sorption of vapors by organic polymers. The approach described has been applied in the past for the design and selection of polymers for acoustic wave sensors. However, the principles apply equally well to the sorption of vapors by polymers used on optical chemical sensors. For example, the polymer could be applied as a thin film to a planar waveguide as the cladding along the length of an optical fiber, or to the end of an optical fiber. Species sorbed into the polymer could then be detected by a change in an optical signal.","PeriodicalId":293004,"journal":{"name":"Pacific Northwest Fiber Optic Sensor","volume":"2574 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131363706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Atwater, J. R. Akse, Jeffrey DeHart, R. R. Wheeler
{"title":"Reagentless chemiluminescence-based fiber optic sensors for regenerative life support in space","authors":"J. Atwater, J. R. Akse, Jeffrey DeHart, R. R. Wheeler","doi":"10.1117/12.207747","DOIUrl":"https://doi.org/10.1117/12.207747","url":null,"abstract":"The initial feasibility demonstration of a reagentless chemiluminescence based fiber optic sensor technology for use in advanced regenerative life support applications in space and planetary outposts is described. The primary constraints for extraterrestrial deployment of any technology are compatibility with microgravity and hypogravity environments; minimal size, weight, and power consumption; and minimal use of expendables due to the great expense and difficulty inherent to resupply logistics. In the current research, we report the integration of solid state flow through modules for the production of aqueous phase reagents into an integrated system for the detection of important analytes by chemiluminescence, with fiber optic light transmission. By minimizing the need for resupply expendables, the use of solid phase modules makes complex chemical detection schemes practical. For the proof of concept, hydrogen peroxide and glucose were chosen as analytes. The reaction is catalyzed by glucose oxidase, an immobilized enzyme. The aqueous phase chemistry required for sensor operation is implemented using solid phase modules which adjust the pH of the influent stream, catalyze the oxidation of analyte, and provide the controlled addition of the luminophore to the flowing aqueous stream. Precise control of the pH has proven essential for the long-term sustained release of the luminophore. Electrocatalysis is achieved using a controlled potential across gold mesh and gold foil electrodes which undergo periodic polarity reversals. The development and initial characterization of performance of the reagentless fiber optic chemiluminescence sensors are presented in this paper.","PeriodicalId":293004,"journal":{"name":"Pacific Northwest Fiber Optic Sensor","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116472375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fiber optic smart civil structures","authors":"P. Fuhr, D. Huston","doi":"10.1117/12.207756","DOIUrl":"https://doi.org/10.1117/12.207756","url":null,"abstract":"The advances in the area of fiber optic sensors have led to applications in various niche areas. Within the past few years, researchers have seemingly led the way in the application of such fiber optic sensors within the civil engineering arena. Specifically, various large civil structures have had differing types of fiber optic sensors installed within and upon these structures leading to measurements not previously available. A review of this `smart structures' research is presented in this paper.","PeriodicalId":293004,"journal":{"name":"Pacific Northwest Fiber Optic Sensor","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123250742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fiber optic strain sensor: comparison of HiBi fibers","authors":"A. Asundi, P. J. Masalkar","doi":"10.1117/12.207753","DOIUrl":"https://doi.org/10.1117/12.207753","url":null,"abstract":"The fundamental mode which propagates in a single mode fiber is actually a degenerate combination of two orthogonally polarized components. In standard single mode fibers, these components travel with the same velocity and so environmental disturbances can cause energy to couple from one component to the other, with the result that the polarization-state of the light varies unpredictably. High birefringence (HiBi) optical fibers are single mode fibers designed to maintain the polarization of the light launched into them to a high degree. This is achieved by introducing birefringence in the core of the optical fiber by prestressing the core or by fabricating the core with an asymmetry. Birefringence causes the two polarized components to travel with different velocities and thus prevents transfer of optical power from one to the other. If linearly polarized light is launched into these fibers along one of the principal stress axes, the state of polarization (SOP) is maintained. However, when linearly polarized light is launched at an angle with the principal axis, the SOP will periodically change from linear to elliptical to linear over a length (beat length) characteristic of the degree of birefringence. In recent years HiBi fibers are finding application in a variety of sensors based on the effect of external stress on the SOP of the output light. The phase difference between the two polarized modes in these fibers can be significantly changed by stretching the fiber. This phenomenon has formed the basis of strain gauge. Here we have evaluated the performance of three different HiBi fibers for sensing axial strain by mounting them on the surface of specimens. In most strain sensing applications, the protective coating over the fibers plays a crucial role in transfer of strain to the fiber core. The effect of the protective coating in each of these fibers is observed. Three fibers were used in our experiment.","PeriodicalId":293004,"journal":{"name":"Pacific Northwest Fiber Optic Sensor","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133899445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Multimode evanescent wave-based sensors: enhancement strategies","authors":"E. Saaski, M. Bizak, Jennifer Yeatts","doi":"10.1117/12.207766","DOIUrl":"https://doi.org/10.1117/12.207766","url":null,"abstract":"There is currently a need for new technologies that are designed specifically for the economical field monitoring of toxins, explosives, and chemical contaminants. The United States has, for example, implemented five regulatory acts to protect its ecologies and its citizens from environmental pollution, and these acts all mandate the monitoring of various chemical contaminants. It is generally accepted that the number of analyses that would be required to meet these new standards would exceed the capacity of all the certified testing labs in the country. New field-portable equipment is needed that can supplement lab-based diagnostic analytical instrumentation, but a continuing problem has been the development of field hardware that can identify and quantify with high specificity a particular species of interest. One of the most promising strategies for performing such narrowly targeted field assays is based on sensors that harness natural immune and protective responses of animals and humans to hone in on a specific compound. This paper discusses the design of a new solid-state portable fluorometer that can be used for the interrogation of a wide range of multimode fiber optic biosensors.","PeriodicalId":293004,"journal":{"name":"Pacific Northwest Fiber Optic Sensor","volume":"10 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132497587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Udd, Kelli Corona-Bittick, K. Slattery, D. J. Dorr
{"title":"Tension and compression measurements in composite utility poles using fiber optic grating sensors","authors":"E. Udd, Kelli Corona-Bittick, K. Slattery, D. J. Dorr","doi":"10.1117/12.207761","DOIUrl":"https://doi.org/10.1117/12.207761","url":null,"abstract":"Composite utility poles have the potential to overcome many of the limitations of wooden poles that are currently widely used. Significant advantages include superior strength and uniformity, light weight for ease of deployment, the ability to be recycled reducing hazardous waste associated with chemically treated wooden poles, and compatibility with embedded fiber optic sensors allowing structural loads to be monitored. This paper describes the usage of fiber optic grating sensors to support structural testing of a 22 foot composite pole.","PeriodicalId":293004,"journal":{"name":"Pacific Northwest Fiber Optic Sensor","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131950465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号
