Optical Strain Detection with Transmitted Light of Fiber Bragg Grating

Transmitted light of fiber Bragg grating (FBG) is exploited in this work for strain detection. Based on shifted wavelength dips/peaks in the spectrum due to different amounts of applied strain, the sensor sensitivity and the square of correlation coefficient (R2) can be obtained. For performance validation, sensitivity and R2 of FBG transmitted light are compared with those of the reflected light. Experimental results suggest that the sensitivity is almost the same for both FBG transmitted and reflected light. However, for the case of R2, the FBG transmitted light has higher R2, indicating that it is more accurate than its counterpart of the reflected light.