US 12,455,455 B2
Lightguide integrity monitoring in a head mounted display
Josh Moore, Elora (CA); Kaveh Moussakhani, Toronto (CA); Jaehong Choi, Waterloo (CA); and Daniel Adema, Kitchener (CA)
Assigned to GOOGLE LLC, Mountain View, CA (US)
Appl. No. 18/730,091
Filed by GOOGLE LLC, Mountain View, CA (US)
PCT Filed Sep. 14, 2022, PCT No. PCT/US2022/043429
§ 371(c)(1), (2) Date Jul. 18, 2024,
PCT Pub. No. WO2023/140897, PCT Pub. Date Jul. 27, 2023.
Claims priority of provisional application 63/300,491, filed on Jan. 18, 2022.
Prior Publication US 2025/0147313 A1, May 8, 2025
Int. Cl. G02B 27/01 (2006.01); G02B 27/00 (2006.01); G02C 11/00 (2006.01); G08B 21/18 (2006.01); H01Q 1/24 (2006.01); H01Q 1/27 (2006.01)
CPC G02B 27/0172 (2013.01) [G02B 27/0081 (2013.01); G02B 27/017 (2013.01); G02C 11/10 (2013.01); G08B 21/182 (2013.01); G02B 2027/014 (2013.01); G02B 2027/0141 (2013.01); G02B 2027/0178 (2013.01); H01Q 1/243 (2013.01); H01Q 1/273 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A head mounted display (HMD) device comprising:
a frame housing a light source to project display light;
a lightguide configured to receive the display light from the light source, the lightguide having an incoupler;
an antenna disposed at the lightguide proximal to the incoupler;
a radio frequency (RF) interface to control the antenna; and
a controller coupled to the antenna and configured to:
monitor the antenna for a change in an electrical characteristic of the antenna; and
generate a signal indicating that the lightguide has been damaged in response to detecting the change in the electrical characteristic of the antenna.