Speckle eliminating device, laser light source and laser projection equipment

Abstract

The invention provides a speckle eliminating device, a laser light source and laser projection equipment, and particularly, the speckle eliminating device comprises an electro-optical crystal and an input matching circuit connected with the electro-optical crystal. An electric field changing along with time is added to the electro-optical crystal through the input matching circuit, so that the refractive index of the electro-optical crystal also changes along with time under the action of the electric field. Because the refractive index of the electro-optical crystal can be changed along withtime, the optical path of the laser beam entering the electro-optical crystal at different time changes randomly. Different optical paths can enable the phases of the emergent laser beams to be different, so that the probability that the phases of the emergent laser beams of the electro-optical crystal are the same or the phase difference is constant is greatly reduced, namely, one of interferenceconditions is damaged, and the coherence degree of the emergent laser is reduced. Therefore, after the speckle eliminating device is applied to a laser light source, the speckle effect can be greatlyreduced, and the display quality of a projection picture is improved.

Description

technical field [0001] The present disclosure relates to the technical field of projection display, and in particular to a speckle elimination device, a laser light source and laser projection equipment. Background technique [0002] Because of its advantages of good monochromaticity, strong directivity, and high luminous flux, laser light sources have been gradually used as light sources in the field of projection display technology in recent years. [0003] However, the high coherence of laser can also cause speckle effect in laser projection display. Speckle means that when a coherent light source irradiates a rough object, the scattered light will have the same wavelength and constant phase. Interference occurs in some parts of the space, and some parts of the space interfere and construct, and some parts interfere and cancel. The final result is granular light and dark spots on the screen. These unfocused spots appear to be in a flickering state to the human eye. Watch...

AI Technical Summary

Problems solved by technology

[0006] Embodiments of the present invention provide a speckle elimination device, a laser light source, and a laser projection device to solve the problem of speckle effects in the application of laser light sources

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