Common-path radial cutting liquid crystal phase shift interference wave-front sensor

Abstract

The invention discloses a common-path radial cutting liquid crystal phase shift interference wave-front sensor. The common-path radial cutting liquid crystal phase shift interference wave-front sensor is composed of a polarizer, a radial cutting system, an LC (Liquid Crystal Phase Modulator), a polarization analyzer, an imaging system and a computer. After a light beam to be detected enters into the wave-front sensor, the polarizer can be rotated, and the polarization direction of the incident light beam can be adjusted; then, two bundles of cutting light beams are formed after the incident light beam passes through the radial cutting system, the two bundles of the cutting light beams share the same light axis, the polarization directions of the two bundles of the cutting light beams are orthogonal, and the apertures of the two bundles of the cutting light beams are zoomed according to the same proportion; the two bundles of the cutting light beams can be directly irradiated to the LC, and the polarization directions of the LC and the enlarged light beams are kept the same; the computer drives the LC to introduce into N (N is larger than or equal to 3) different phase shifts between the cutting light beams, a polarized component, of which the polarization direction is consistent with that of the polarization analyzer, is obtained in the two bundles of the cutting light beams after passing through the polarization analyzer, and interference is generated; interference images are collected by the imaging system and are sequentially input into the computer in a time-division way, and the wave-front phase of the light beam to be detected can be reconstructed by analyzing and calculating. The common-path radial cutting liquid crystal phase shift interference wave-front sensor disclosed by the invention has the advantages that the structure of an optical system is simple, the impact of environmental vibration and non-common-path error can be restrained, the visibility of interference fringes is continuous and adjustable, and the wave-front detection accuracy is high.

Description

technical field [0001] The invention relates to a key device in the technical fields of adaptive optics and wavefront detection, in particular to a common light path direction shearing liquid crystal phase-shifting interference wavefront sensor. Background technique [0002] The wavefront sensor is an important key device in the adaptive system, which is used to detect the wavefront phase of the incident beam. According to the relationship between the measured signal and the wave surface, wavefront sensors can be divided into three categories: the first category restores the wavefront phase by measuring the wavefront slope, such as Hartmann wavefront sensors, shearing interferometers, etc.; the second category The wavefront phase is restored by measuring the wavefront curvature, such as a curvature wavefront sensor; the third type is to directly restore the wavefront phase, and the typical representative is a point diffraction interferometer. [0003] Of all wavefront senso...

AI Technical Summary

Problems solved by technology

This sensor can solve the problem of low measurement accuracy of current common optical path shearing interference technology and poor anti-interference ability of non-common optical path shearing interference system based on phase-shifting wavefront restoration technology. It well integrates common optical path, shearing interference, The respective advantages of liquid crystal phase modulation and phase shifting wavefront restoration technology have the characteristics of high light energy utilization rate, high contrast of interference fringes, strong resistance to environmental vibration and atmospheric interference, self-referencing interference, and high accuracy of wavefront restoration.

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