Patent ID: 11966060
Assignee: JIAXING UPHOTON OPTOELECTRONICS TECHNOLOGY CO., LTD.
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. An optical waveguide device for display, comprising an input section and an output section, in which the input section comprises a first waveguide substrate and a first relief grating formed on a surface of the first waveguide substrate, and the first relief grating has a first grating vector and is used to couple light irradiated on the first relief grating at an incident angle within a predetermined FOV range, into the first waveguide substrate through diffraction of a predetermined order, in such a way that the light propagates in the first waveguide substrate through total reflection in substantially the direction of the first grating vector, so as to be coupled out of the waveguide device for display by the output section, wherein:
the first relief grating has a first refractive index n1, the first waveguide substrate has a second refractive index n2, and n2<n1, such that a first maximum average number of reflections that a light beam of any incident angle within the predetermined FOV range is subjected to on the surface of the first waveguide substrate after the diffraction of the predetermined order before leaving a region where the first relief grating lies, is N, and N≤2, wherein: when N≤1, N≤M−0.25; when 1<N≤1.5, N≤M−0.5; and when 1.5<N≤2, N≤M−0.75, wherein M is a second maximum average number of reflections that the light beam is subjected to on the surface of the first waveguide substrate after the diffraction of the predetermined order before leaving the region where the first relief grating lies, where the refractive index of the first waveguide substrate is equal to the first refractive index n1.