• Journal of Sensor Science and Technology
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• v.9 no.2
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• pp.96-105
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• 2000

Fiber optic TR-EFPI(total reflected extrtinsic Fabry-Perot interferometric) sensor was developed to measure the strain of structures, such as building, bridge, aircraft, etc. It has been difficult to distinguish the increase and decrease of the strain from the conventional fiber optic EFPI sensor because their signals only have a sinusoidal wave pattern related to the change of strain. Also, the absolute strain could not be measured by the simple fiber optic EFPI sensor. In this study, in order to measure the magnitude of strain with the direction of strain, the fiber optic sensor was simply constructed with the total reflected EFPI sensor probe. This probe was manufactured with a single mode fiber and a mirror coated fiber in a silica glass capillary tube. The output signal of this fiber optic TR-EFPT sensor can give the information about the magnitude and the direction of strain. The loading-unloading test was performed by the universal testing machine with alluminum beam specimen to compare the strain from fiber optic TR-EFPI sensor with the value from electrical strain gauge. In the result of this experiment. the strain from fiber optic TR-EFPI sensor had a good agreement with the values from the electrical strain gauge.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.05a
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• pp.31-34
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• 2002

A study on the method that can measure the internal strain of composite materials is performed to monitor the health status of composite structures. A fiber optic sensor was constructed using the total reflected extrinsic Fabry-Perot interferometer(TR-EFPI) probe with a broadband light source. Result obtained from electrical strain gage adhered on the aluminum beam specimen was compared with that from the fiber optic TR-EFPI sensor and showed a good agreement. It was found that fiber optic TR-EFPI sensor system was adequate for monitoring the strain and thus failure processes in the interior of composite materials.

• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.254-255
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• 2000

광섬유 전반사형 외부 패브리-패로(TR-EFPI total reflected extrinsic Fabry-Perot inteferometric) 센서를 개발하여 외부 물리량의 변화 크기와 방향을 간편하게 알아낼 수 있도록 하였다. 이 TR-EFPI 센서 탐촉자는 한 개의 단일모드 광섬유와 한 개의 거울도금 광섬유를 모세 유리관 안에 고정하여 공기간극을 형성함에 의하여 만들어진다. 또한 외부 물리량은 변형률을 측정할 수 있도록 알루미늄 시험편의 표면에 부착하고 만능시험기를 사용하여 하중을 증감시키면서 변형률의 변화를 측정하도록 하였다. (중략)