We describe an optical technique using the principles of a Pohl interferometer and divergent laser beams for measuring optical path changes in the spaces between interdigital electrodes. We present experimental results of the electric-field-induced optical path changes in an electrode space using a LiNbO3 sample.
Lowell L. Wood,
John H. Miller,
"Electric field-induced optical path change profiling using a Pohl interferometer," Optical Engineering 41(11), (1 November 2002). https://doi.org/10.1117/1.1512662