High-luminous-efficiency diffraction waveguide element for AR near-to-eye display equipment

Abstract

The invention discloses a high-luminous-efficiency diffraction waveguide element for AR near-to-eye display equipment. The high-luminous-efficiency diffraction waveguide element comprises at least two diffraction waveguide layers, wherein each diffraction waveguide layer comprises a substrate, and an incident grating, a turning grating and an emergent grating which are distributed on the substrate at intervals, and the positions of the incident grating, the turning grating and the emergent grating on the substrate of the same diffraction waveguide layer are matched; the diffraction waveguide layers are stacked from top to bottom to form an integral diffraction waveguide structure, and in the stacked and combined diffraction waveguide structure, the positions of the incident gratings of the diffraction waveguide layers in the y-axis direction are mutually staggered; and the emergent gratings of the diffraction waveguide layers coincide in position in the y-axis direction. According to the diffraction waveguide device, light beams in different incident directions can be distributed to different diffraction waveguide layers for conduction, light energy waste in the light beam conduction process is reduced, the light efficiency is greatly improved, meanwhile, stray light is reduced, and the display quality of the diffraction waveguide device is improved.

Description

technical field [0001] The invention relates to the field of diffraction waveguides, in particular to a diffraction waveguide device. Background technique [0002] As virtual reality and augmented reality technologies are gradually recognized and accepted by people, near-eye display devices have developed rapidly. The near-eye display in augmented reality technology can superimpose virtual images on the real scene, and at the same time have perspective characteristics, without affecting the normal observation of the real scene. The method of coupling virtual images into human eyes by using traditional optical devices has been adopted, including: prisms, semi-transparent mirrors, free-form surface waveguides, mirror array waveguides, diffractive waveguides, etc. Diffraction waveguide display technology uses diffraction grating to realize the incidence, turning and exit of light, and uses the principle of total reflection to realize light transmission, and transmits the image...

AI Technical Summary

Problems solved by technology

Since there is a part of the turning grating 114 outside the two ends of the exiting grating 116 in the y-axis direction, the resulting light energy is wasted, such as Figure 2A In this part of the deflection grating 114 transmission part of the beam 223 and Figure 2B Part of the light beam 224 transmitted in the center, because it cannot enter the exit grating 116, can not be used and wasted, which affects the light energy utilization efficiency of the system, and this part of wasted light will generate stray light in the diffraction waveguide, affecting the display effect

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