Polarization interferometer optical voltage detector utilizing movement of interference fringe

摘要

Polarized light is input to an optical modulator typically consisting of an electrooptic crystal. The polarization state of the input light is changed in accordance with a voltage being applied to the optical modulator. Receiving the light output from the optical modulator, a polarization interferometer produces an interference fringe on the input surface of a photodetector such as a streak camera and a CCD line sensor. Based on an output signal of the photodetector, an analyzing device calculates a pitch and a movement distance of the interference fringe to determine the voltage being applied to the optical modulator.