公开(公告)号：US20240061165A1

公开(公告)日：2024-02-22

申请号：US18384838

申请日：2023-10-28

Applicant: AGC Inc.

Inventor： Motoshi NAKAYAMA ,  Mitsuo OSAWA

IPC: F21V8/00 ,  G02B27/01

CPC classification number: G02B6/0016 ,  G02B6/0036 ,  G02B6/0065 ,  G02B27/0172

Abstract: A light guide element includes a light guide substrate that is a single-layer light guide substrate; and a diffraction layer formed on the light guide substrate. The diffraction layer includes a first diffraction grating configured to in-couple light into the light guide substrate; and a second diffraction grating configured to outcouple totally internally reflected light having propagated in the light guide substrate out of the light guide substrate. The first diffraction grating in-couples the incident light in a range of 60 degrees or more including a direction normal to substrate, for at least one of first wavelength of 450 nm±20 nm, second wavelength of 530 nm±20 nm, and third wavelength of 630 nm±20 nm. The second diffraction grating outcouples the totally internally reflected light in a range of 60 degrees or more including the direction normal to substrate, for at least one of the first, second, and third wavelengths.