Spherical wavefront curvature radius measuring device and measuring method

Abstract

The invention discloses a spherical wavefront curvature radius measuring device which comprises an initial wavefront adjusting module, a spherical wave generating module and a radial shearing interference module. The spherical wave generation module comprises a transmission-type spherical wave generation module and a reflection-type spherical wave generation module; coupled beams are output from a laser, the coupled beams are used as initial input wavefronts for generating two different types of spherical waves, and the initial wavefronts are adjusted by an initial wavefront adjustment module and then enter a transmission-type spherical wave generation module and a reflection-type spherical wave generation module respectively; initial input wavefront deforms correspondingly after passing through the transmission type spherical wave generation module and the reflection type spherical wave generation module and then is transmitted to the radial shearing interference module, final output wavefront is received by the polarization camera, and curvature radius measurement is achieved according to obtained original spherical wavefront distribution. The invention further discloses a method for measuring the curvature radius of the spherical wavefront, and the method has the advantages that large-curvature spherical wavefront recovery is achieved, the method is not affected by vibration operation, and efficient data dynamic collection is achieved.

Description

technical field [0001] The invention belongs to the field of optical sensing and measurement of precision instruments, and in particular relates to a spherical wavefront curvature radius measuring device and a measuring method. Background technique [0002] The measurement of spherical wavefront is a crucial technical indicator in other industrial fields such as optical surface profile inspection and laser beam quality diagnosis. In addition to Shaker-Hartmann wavefront sensors and pyramid techniques, which have lateral resolution limitations, several interferometry techniques can be used to achieve spherical wavefront measurements. For example, point diffraction interferometry (PDI) can obtain a sphere based on a reference wave generated by a pinhole and interfere with the wavefront to be measured. Although it can accurately measure the wave front, in PDI the reference wave and the measurement wave are separated, and the measurement result is very sensitive to environmenta...

AI Technical Summary

Problems solved by technology

However, the use of CRSI for testing spherical wavefronts has not been fully discussed at present, since it was originally designed for measuring planar wavefronts and their small perturbations

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