General calibration method for phase measurement of spatial light modulator

Abstract

The invention discloses a general calibration method for phase measurement of a spatial light modulator. The method comprises the following steps: (a) generating a phase grey-scale map, and collectinga light field distribution map; (b) when the image quality is judged to be good manually, generating a 0-255 phase grey-scale map; (c) periodically, circularly and sequentially loading, automaticallycollecting a light field distribution diagram, calculating fringe and zero-order centroid offset, and further calculating a gray-scale phase mapping table; (d) carrying out data fitting on the gray-scale phase mapping table, carrying out comparative analysis on the data fitting and expected gray-scale phase mapping, if the data fitting and the expected gray-scale phase mapping meet the expectation, finishing calibration, and if not, performing Gamma correction on the acquired and calculated data and the expected data to form a new Gamma mapping table, and returning to the step (c) when writing the new Gamma mapping table into the Gamma mapping table until the calibration is completed.

Description

technical field [0001] The invention relates to the field of development and test application of a spatial light modulator. Specifically, it is a calibration method for the phase capability of the spatial light modulator, which is used to quickly calibrate and measure the gray phase curve of the spatial light modulator. Background technique [0002] The measurement and calibration of the phase capability of spatial light modulator is very critical to its use. The mainstream methods for the phase modulation characteristics of spatial light modulators are as follows: 1. Double-slit interferometry. This method needs to process two high-precision reticles, the optical path needs to be strictly coaxial, the construction is complicated, and the system has poor anti-interference. 2. The Mach-Zehnder interferometer method, which has a complex optical path, is greatly affected by system aberrations and system stability, and the later data processing is more complicated and the accur...

AI Technical Summary

Problems solved by technology

The mainstream methods for the phase modulation characteristics of spatial light modulators are as follows: 1. Double-slit interferometry. This method needs to process two high-precision reticles, the optical path needs to be strictly coaxial, the construction is complicated, and the system has poor anti-interference performance.

2. The Mach-Zehnder interferometer method, which has a complex optical path and is greatly affected by system aberrations and system stability, and the later data processing is more complicated and the accuracy is not high

3. Tieman-Green interferometer method, although this method is much simpler than the Mach-Zehnder interferometer optical path, and the system anti-interference is relatively better, but the system aberration has a great influence on the detection accuracy

[0003] Therefore, in mass production or rapid measurement of the phase capability of spatial light modulators, the existing methods have low precision, relatively complicated equipment, and weak anti-interference ability, which makes it impossible to quickly detect them using computer image processing capabilities.

Images