Measuring dynamic strain of structures using a gold-deposited extrinsic Fabry Perot interferometer

Dae-Hyun Kim, Joong-Wan Park, Hyun-Kyu Kang, Chang-Sun Hong, Chun-Gon Kim
2002 Smart materials and structures (Print)  
In this paper, we present a new type of extrinsic Fabry-Perot interferometer (EFPI) for measurement of dynamic strain. Gold was deposited on the second reflecting surface of the optical fiber in this sensor to increase its reflectivity. Thus, we have termed it a gold-deposited EFPI (G-EFPI). If a gap between two reflecting surfaces increases, the loss of intensity of the light that passes through the gap increases, causing a subsequent decrease in the output intensity of the sensor. Conversely,
more » ... sensor. Conversely, if the gap decreases, the amount of loss decreases and the output intensity increases. Therefore, it is possible to determine the variation of the gap size by observing the output intensity of the sensor. Finally, the dynamic strain of a composite specimen was measured successfully using the G-EFPI.
doi:10.1088/0964-1726/12/1/301 fatcat:n7falojjd5etnll6tlbnuikj6a