US 12,222,533 B1
Optical waveguide device and display device
Yuming Song, Beijing (CN); Zhentao Fan, Beijing (CN); Lei Sui, Beijing (CN); and Kehan Tian, Beijing (CN)
Assigned to UPHOTON TECHNOLOGY (Beijing) CO., LTD., Beijing (CN)
Filed by UPHOTON TECHNOLOGY (Beijing) CO. LTD., Beijing (CN)
Filed on Aug. 9, 2024, as Appl. No. 18/798,945.
Claims priority of application No. 202311725465.9 (CN), filed on Dec. 15, 2023.
Int. Cl. F21V 8/00 (2006.01); G02B 27/01 (2006.01)
CPC G02B 6/0016 (2013.01) [G02B 6/0018 (2013.01); G02B 6/0036 (2013.01); G02B 27/0172 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An optical waveguide device, comprising:
a waveguide substrate having a first surface with a coupling-in region and an opposite second surface with a reflecting region, and further having a coupling-out region;
a coupling-in grating disposed in the coupling-in region of the first surface of the waveguide substrate and configured to receive input light within a predetermined field of view, diffract at least a portion of the input light to form positive first-order diffraction light and zero-order diffraction light, and couple the light into the waveguide substrate, such that the light can propagate within the waveguide substrate through total reflection, wherein a light spot of the zero-order diffraction light first projected onto the second surface has a first profile, and the first profile is at least partially located in the reflection region;
a coupling-out grating disposed in the coupling-out region of the waveguide substrate and configured to couple at least a portion of the light propagating into the coupling-out grating out of the waveguide substrate through diffraction;
a reflection grating disposed in the reflection region of the second surface and configured such that a portion of the zero-order diffraction light forms positive first-order reflection light through diffraction and the positive first-order reflection light is propagated to the coupling-out grating through total reflection in the waveguide substrate;
wherein a projection of the reflection region on the first surface at least partially overlaps with the coupling-in region, and a ratio of an area of an overlapping portion to an area of the coupling-in region is less than or equal to 40%.