US 12,449,659 B2
Optical device
James Leighton, Burghfield Common (GB)
Assigned to SNAP INC., Santa Monica, CA (US)
Appl. No. 17/995,660
Filed by Snap Inc., Santa Monica, CA (US)
PCT Filed Apr. 7, 2021, PCT No. PCT/EP2021/059093
§ 371(c)(1), (2) Date Oct. 6, 2022,
PCT Pub. No. WO2021/204894, PCT Pub. Date Oct. 14, 2021.
Claims priority of application No. 20168515 (EP), filed on Apr. 7, 2020.
Prior Publication US 2023/0161163 A1, May 25, 2023
Int. Cl. G02B 27/01 (2006.01); F21V 8/00 (2006.01); G02B 6/42 (2006.01); G02B 27/42 (2006.01)
CPC G02B 27/0172 (2013.01) [G02B 6/0035 (2013.01); G02B 6/4214 (2013.01); G02B 27/4272 (2013.01); G02B 2027/0123 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An optical device for expanding input light and outputting the expanded light, the optical device comprising:
a waveguide;
an input optical element configured to receive light incident on a first side of the waveguide and comprising a curved, smooth, continuous input reflective surface configured to reflect the received light into the waveguide;
an intermediate diffractive optical element configured to receive light in the waveguide from a first direction, and provide an expansion of the received light in a second direction perpendicular to the first direction; and
an output optical element comprising a curved, smooth, continuous output reflective surface configured to reflect the expanded light out of the waveguide towards a viewer,
wherein the waveguide is configured to guide light along an optical path from the input optical element to the intermediate diffractive optical element and from the intermediate diffractive optical element to the output optical element.