Abstract:
광섬유센서는미켈슨센서부분과마흐-젠더센서부분을가질수 있다. 제1 분할기-결합기가제1 섬유부분과제2 섬유부분사이에서입력광을분할하도록구성될수 있다. 제1 편광-위상컨쥬게이션디바이스가제1 섬유부분에대응하는입력광의편광위상을컨쥬게이트하도록구성될수 있고, 제2 편광-위상컨쥬게이션디바이스가제2 섬유부분에대응하는입력광의편광위상을컨쥬게이트하도록구성될수 있다. 제1 및제2 편광-위상컨쥬게이션디바이스각각은검출기를향해서그리고각각의제1 및제2 섬유부분을통해광을반사하도록구성될수 있다. 결합기가제1 섬유부분에서의광을제2 섬유부분에서의광과결합하도록구성될수 있고, 제3 섬유부분이결합기로부터광을수광하여제2 검출기를조명하도록구성될수 있다.
Abstract:
PURPOSE: An apparatus and a method for measuring the tension of a tension member using an optical fiber sensor are provided to measure the deformed rate and the tension of the tension member by measuring the displacement of a load cell body. CONSTITUTION: An apparatus for measuring the tension of a tension member(11) using an optical fiber sensor comprises a load cell body, an optical fiber sensor, and a case. The load cell body forms compression force by the tension of the tension member. The optical fiber sensor is installed in a direction that the compression force is formed in the load cell body to measure the displacement of the load cell body due to the compression force. The case shields the outer surface of the load cell body installed in the optical fiber sensor.
Abstract:
La présente invention concerne un procédé et un dispositif pour l'analyse d'une structure par tomographie et corrélation de champ acousto-élastique diffus. Une fibre optique comportant une pluralité de points de mesure de type FBG (Fiber Bragg Grating), comportant des capteurs de type réseau de Bragg, est déployée dans ou sur la structure à analyser. La méthode comprend l'émission de lumière, dans la fibre optique, et la mesure par corrélation pour chaque couple de capteurs FBG. Dans un développement, une imagerie préalable de la structure est réalisée par reconstruction des vitesses de propagation. D'autres développements comprennent : la détermination des positions des capteurs FBG, l'étalonnage de la tomographie, la configuration en rosette des capteurs constituant les points de mesure, l'emploi d'une pluralité de fibres optiques, de multiplexeurs, de lasers, de circulateurs optiques, de capteurs optiques omnidirectionnels, de sources de bruit actives, tels des transducteurs piézoélectrique, intégrés ou non dans la structure.
Abstract:
Fiber optic sensors include sensor regions in which an optical phase is modulated by an analyte to be detected. A long period fiber grating (LPG) is coupled to a coating that is arranged to selectively interact with the analyte. The resulting phase change is detected based on a transmission spectrum associated with the LPG so that analyte is detected and quantified. A plurality of such sensors is distributed along a fiber to form a sensor array that can be situated to detect analyte at a plurality of discrete regions.
Abstract:
A fiber optic sensor interrogation system with inbuilt passive power limiting capability that provides improved safety performance for use in explosive atmospheres.
Abstract:
A mercury detection system that includes a flow cell having a mercury sensor, a light source and a light detector is provided. The mercury sensor includes a transparent substrate and a submonolayer of mercury absorbing nanoparticles, e.g., gold nanoparticles, on a surface of the substrate. Methods of determining whether mercury is present in a sample using the mercury sensors are also provided. The subject mercury detection systems and methods find use in a variety of different applications, including mercury detecting applications.
Abstract:
A monitorização do processo de cura do betão é de elevada importância, nomeadamente em obras de arte de elevada envergadura, permitindo controlar de forma mais rigorosa o momento de descofragem, prevenindo acidentes de trabalho, em obras especiais betonadas em condições adversas devido ao clima ou pelas próprias condições de betonagem. O método proposto permite monitorar o estado do processo de cura de uma estrutura de betão, recorrendo a fibras ópticas de plástico. Em comparação com os processos actuais comerciais de monitorização, o método proposto permite determinar directamente a presença de água na mistura, ao contrário de métodos baseados na medição do aumento de temperatura resultante do processo exotérmico do betão. A utilização de fibras ópticas de plástico embutidas no elemento estrutural a analisar, resulta num processo de monitorização com um baixo custo de implementação associado. O método proposto apresenta ainda uma resolução suficiente para analisar o processo de cura até à sua estabilização.
Abstract:
An apparatus for detecting an object capable of emitting light. The apparatus includes a light source (102) and a waveguide (110). The waveguide (110) includes a core layer (112) and a first cladding layer (114). At least one nanowell (120) is formed in at least the first cladding layer (114). The apparatus further includes a light detector (106). The light detector (106) can detect light emitted from a single molecule object contained in the at least one nanowell (120).