Preparation method of a vector compensating volume Bragg grating angle deflector

Abstract

The invention provides a preparation method of a vector compensating volume Bragg grating angle deflector. The present invention designs a sample holder according to the cone angle of the incident beam, uses the sample holder to expose the sample, uses a muffle furnace to heat-treat the sample after the exposure, polishes the front and rear surfaces of the sample after the heat treatment, and coats the front and rear surfaces of the sample with a 1064nm standard anti-reflection film , made into a vector compensating volumetric Bragg grating angle deflector. The method of the invention can perform vector compensation on the volume Bragg grating recorded in the sample, so that the cone-angle incident beam meets the Bragg condition, can effectively improve the diffraction efficiency of the volume Bragg grating angle deflector for the cone-angle incident beam, and is applied to two-dimensional beam scanning The system can realize high-efficiency beam scanning in two-dimensional directions, has the advantages of simple preparation method and mass production, and has important practical prospects in the technical field of two-dimensional laser beam scanning.

Description

technical field [0001] The invention relates to a volume Bragg grating, in particular to a preparation method of a vector compensating volume Bragg grating angle deflector. Background technique [0002] Traditional volume Bragg gratings recorded in photothermographic glass can achieve large-angle beam deflection when the incident beam satisfies the Bragg condition ( figure 1 (a)), and has high diffraction efficiency, low absorption, scattering loss, and high power tolerance. Liquid crystal optical phased array can realize small angle range (typically ±3°~5°), high-precision beam deflection, combined with volume Bragg grating, it can be made into two-dimensional beam scanning system, realizing two-dimensional direction, large angle , Quasi-continuous beam scanning. [0003] For the two-dimensional beam scanning system, it is realized by the scheme of "liquid crystal optical phased array-horizontal deflector Bragg grating-liquid crystal optical phased array-vertical deflecto...

AI Technical Summary

Problems solved by technology

However, when the beam is incident on the vertical deflector Bragg grating after being horizontally deflected, the incident beam and the designed beam incident plane satisfying the Bragg condition ( Figure 4 -YOZ surface) has a cone angle of 0°~45°, which causes the incident beam to deviate from the Bragg incidence condition ( figure 1 (b)), the actual working wavelength does not match the designed working wavelength, which leads to a decrease in the diffraction efficiency of the incident beam by the two-dimensional beam scanning system

At present, no relevant documents or patents have been seen to provide a better solution to this problem.

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