Patent ID: 9417608
Filing Date: 2016-08-16
CPC Classification: G03H

Claim Text:
1. An apparatus for detecting an interference fringe pattern comprising: a laser source configured to emit a laser beam with a frequency of v, an acoustic optical modulator configured to generate, from the laser beam, a first beam with a frequency of v a first beam splitter configured to split the first beam into a first reference beam and a first object beam, the first object beam being led to a sample with a first incident angle; a second beam splitter configured to split the second beam into a second reference beam and a second object beam, the second object beam being led to the sample with a second incident angle different from the first incident angle; and a detector configured to detect, at an exposure time, an image composed of a first interference fringe pattern, based on the first reference beam and the first object beam, and a second interference fringe pattern, based on the second reference beam and the second object beam, wherein the inverse of Δv (Δv=|v wherein the exposure time is set at milli-second order and the inverse of Δv is set at sub micro-second order.