Method and device for eliminating black grid effect of phase-type spatial light modulator

Abstract

The invention discloses a method for eliminating the black grid effect of a phase-type spatial light modulator. This method suppresses the black grid effect by combining phase compensation with spatial filtering technology. First, through the linear phase compensation of the phase modulation diagram, the modulated effective light wave deviates from the main optical axis to propagate, and then according to the size of the compensated phase, a spatial filter is placed behind the spatial light modulator, which passes the effective light wave and blocks out Zero-frequency light and advanced diffracted light, so that there is only effective information on the diffracted image plane, without the central bright spot and the advanced diffraction image, that is, the suppression of the black grating effect of the phase-type spatial light modulator is realized, and its performance is improved. Practical application value in optical information processing.

Description

technical field [0001] The invention relates to a method for eliminating the black grid effect of a phase-type spatial light modulator, which belongs to the optical information processing technology. Background technique [0002] A Spatial Light Modulator (SLM) is a device that can modulate a certain parameter of a light wave under the control of a signal source, such as modulating the amplitude through absorption, modulating the phase through the refractive index, and through the rotation of the polarization plane. Modulate the polarization state, etc. It effectively utilizes the parallel, interconnected and high-speed processing capabilities of light, enabling it to spatially modulate light beams in real time, becoming the core component of real-time optical information processing systems, and playing an increasingly important role in the field of modern optics It is the basic component and key device in the research of optical and photoelectric hybrid systems for optical...

AI Technical Summary

Problems solved by technology

[0005] The "black grid effect" is a phenomenon inherent in SLM, which exists even when no image is written to the SLM, and when a modulated image is written, the center of the diffraction image of the written image coincides with the central bright spot , the center of its advanced diffraction image will also coincide with the advanced diffraction bright spot of the spatial light modulator, so that the center of the image on the receiving surface is always coupled with the inherent multi-level diffraction bright spot of the spatial light modulator and cannot be separated , resulting in a serious decline in the quality of the diffraction image, or even unusable

This effect affects the application of spatial light modulators, and has a very adverse impact on the application of spatial light modulators, which greatly limits the application of spatial light modulators in optical information processing.

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