Transmitted Phase Measurement System of A Guided-Mode Resonance Device Based on Interference Fringe Image

This paper reports a phase measurement system of a guided-mode resonance (GMR) device to detect the transmitted phase difference between s- and p-polarization of the incident light under the different incident angles. The GMR device is a resonance grating waveguide and can be used as a sensor to detect the refractive index change on the grating surface. The experimental results of the compact common-path phase measurement system are reported. Image processes are applied to the recorded images to obtain the accurate fringe shifting value to convert to phase value. The measurement results are compared with the electro-optic heterodyne interferometer and simulation (Rsoft DiffractMOD) results.