Apparatus and method for measuring phase retardation

Abstract

The present invention discloses an apparatus and a method for measuring phase retardation. The apparatus comprises: a monochromatic light source, being capable of radiating a pulsed light beam; a photodetector, deposed on a side of the monochromatic light source; a polarizer, deposed between the monochromatic light source and the photodetector; and a beam splitting apparatus, deposed between the polarizer and the photodetector. The method utilizing the apparatus comprises the following steps: interposing an object between the polarizer and the beam splitting apparatus; generating a polarized light beam by transmitting the pulsed light beam through the polarizer; generating a phase retarded light beam by transmitting the polarized light beam through the object; dividing said phase retarded light beam into a first polarized ray and a second polarized ray by transmitting the phase retarded light beam into the beam splitting apparatus; detecting a time difference between pulse peak of the first polarized ray and pulse peak of the second polarized ray; and calculating a phase retardation value according to the time difference.

Dependencies are inferred from the claim text.