US 11,747,538 B2
LED illuminated waveguide projector display
David Woods, Chinnor (GB)
Assigned to Snap Inc., Santa Monica, CA (US)
Appl. No. 17/755,855
Filed by Snap Inc., Santa Monica, CA (US)
PCT Filed Oct. 15, 2020, PCT No. PCT/GB2020/052600
§ 371(c)(1), (2) Date May 10, 2022,
PCT Pub. No. WO2021/094706, PCT Pub. Date May 20, 2021.
Claims priority of application No. 1916369 (GB), filed on Nov. 11, 2019.
Prior Publication US 2022/0397716 A1, Dec. 15, 2022
Int. Cl. F21V 8/00 (2006.01); G02B 3/00 (2006.01)
CPC G02B 6/0018 (2013.01) [G02B 3/0056 (2013.01); G02B 6/0028 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A projection display comprising:
a waveguide comprising an input grating having a plurality of linear diffractive features, the input grating configured to couple in light into the waveguide; and
an array of LEDs configured to form an illumination pupil which is optically relayed as an input pupil onto the input grating, at the input grating the input pupil having a shape that is larger in a direction parallel to the linear diffractive features than in a direction perpendicular to the linear diffractive features.