Instantaneous phase-shift transverse shear interferometer

Abstract

The invention relates to an instantaneous phase-shift transverse shear interferometer, which aims to solve the problems of troublesome operation, high requirements of systems for environment, large influence of environment on acquisition results in the prior art. The instantaneous phase-shift transverse shear interferometer provided by the invention comprises a parallel polarization beam splitter 2, a one-quarter wave plate 3, a two-dimensional rectangular grating 4, a first convex lens 5, a spatial filter 6, a second convex lens 7, a polaroid array 8 and a CCD 9 which are concentrically arranged in turn on a main optical axis, wherein the CCD 9 is connected with a computer 1; the direction of an optical axis of a crystal of the parallel polarization beam splitter 2 and an incident surface are at an included angle of 45 degrees; the direction of a fast axis of the one-quarter wave plate 3 is positioned on a plane at an angle of 45 degrees to the plane consisting of the direction of the optical axis of the crystal of the parallel polarization beam splitter 2 and the main optical axis; and the spatial filter 6 is arranged on a back focal plane of the first convex lens 5 and a front focal plane of the second convex lens 7. The interferometer has the advantages of reducing the requirements of the systems for environment and increasing measurement accuracy, along with easy operation.

Description

Technical field: [0001] The invention relates to the technical field of optical interferometry instruments, in particular to a phase shift transverse shear interferometer, in particular to an instantaneous phase shift transverse shear interferometer. Background technique: [0002] The transverse shearing interferometry divides the wavefront to be measured into two identical wavefronts to be measured by a certain optical-mechanical system, and the two formed wavefronts to be measured produce a certain displacement in space. The application of transverse shearing technology avoids the systematic error introduced when standard wavefront is used in optical interference. Transverse shear interference simplifies the structure of the measurement system to a certain extent, reduces the accuracy requirements of the optical components in the test system, and also improves the measurement accuracy of the system to a certain extent. Introducing phase-shifting technology into the transv...

AI Technical Summary

Problems solved by technology

[0009] The present invention provides an instantaneous phase-shift transverse shear interferometer to overcome the problems of troublesome operation and high environmental requirements of the system in the prior art

Images