76 / 2021-06-04 16:40:10

基于法布里-珀罗干涉仪原理的高分辨电致伸缩效应光学测量方法

In recent years, piezoelectric materials attracted significant research interest, especially in the fields of aerospace, military, smart grid, industrial automation, and healthcare. Based on the electrostrictive effect, accurate measurement of the micro-strain of piezoelectric materials can achieve high-precision measurement of the electrostriction coefficient. This paper introduces a measurement system of electrostrictive effect of dielectrics based on optical fiber Fabry-Perot (F-P) interferometer. By utilizing the structural characteristics of the F-P interferometer, a piezoelectric ceramic disc (PCD) serves as a sensitive medium in an optical fiber F-P cavity. Upon applying a voltage to the PCD, the induced deformation of cavity length will lead to a change in the interference spectrum generated by the reflected light. Thus, the deformation of the F-P cavity could be detected from the wave shift in the interference spectrum. Such measurement device based on FP interference principle has the advantages of high sensitivity, immunity to electro-magnetic interference, low cost etc. As demonstrated by the results, a consistent linear relationship was obtained between the generated deformation and the excitation signal under various electric field strengths. The electrostriction coefficient was 1.05×10^-14m²/V². The measured resolution could reach to the level of 10 pm.