US 12,379,599 B2
Light guide and near-eye display apparatus
Haifeng Zhou, Dongguan (CN); Liming Liu, Dongguan (CN); and Ziqian Ding, Dongguan (CN)
Assigned to Huawei Technologies Co., Ltd., Shenzhen (CN)
Filed by HUAWEI TECHNOLOGIES CO., LTD., Guangdong (CN)
Filed on Nov. 14, 2023, as Appl. No. 18/508,930.
Application 18/508,930 is a continuation of application No. PCT/CN2022/093392, filed on May 17, 2022.
Claims priority of application No. 202110546093.8 (CN), filed on May 19, 2021.
Prior Publication US 2024/0077736 A1, Mar. 7, 2024
Int. Cl. G02B 27/01 (2006.01); F21V 8/00 (2006.01)
CPC G02B 27/0172 (2013.01) [G02B 6/0016 (2013.01); G02B 6/0036 (2013.01); G02B 2027/0178 (2013.01)] 20 Claims
OG exemplary drawing
 
16. A light guide, comprising:
a light guide plate; and
a two-dimensional grating that is disposed on a first surface of the light guide plate, wherein:
the first surface is closer to an eye than a second surface of the light guide plate when the light guide is in use, the two-dimensional grating comprises a plurality of grating units, the plurality of grating units are arranged at an interval of a first distance along a first direction and are arranged at an interval of a second distance along a second direction, and the first direction intersects with the second direction;
the two-dimensional grating comprises a light egress area and a light ingress area that are arranged along a third direction, a fourth direction is perpendicular to the third direction, the first direction, the second direction, the third direction, and the fourth direction are located on a same plane, and any two directions of the first direction, the second direction, the third direction, and the fourth direction do not overlap; and
each grating unit of the plurality of grating units is configured to diffract one incident light beam into at least three emergent light beams, wherein the grating unit is configured to generate a first grating vector, a second grating vector, and a plurality of combined grating vectors, wherein the first grating vector is perpendicular to the first direction, the second grating vector is perpendicular to the second direction, a combined grating vector is a vector sum of the first grating vector at a diffraction order M1 and the second grating vector at a diffraction order M2, and M1 and M2 are integers.