US 12,405,420 B2
Light output devices and light outputting methods for optical systems
Yongming Tu, Redwood City, CA (US); Jeremy D. Witmer, San Jose, CA (US); Huiyang Deng, San Jose, CA (US); Mark A. Arbore, Los Altos, CA (US); Mohsen Kamandar Dezfouli, San Jose, CA (US); Alfredo Bismuto, Sunnyvale, CA (US); and Petr Markov, San Francisco, CA (US)
Assigned to APPLE INC., Cupertino, CA (US)
Filed by Apple Inc., Cupertino, CA (US)
Filed on Sep. 20, 2022, as Appl. No. 17/949,066.
Claims priority of provisional application 63/247,526, filed on Sep. 23, 2021.
Prior Publication US 2023/0089758 A1, Mar. 23, 2023
Int. Cl. G02B 6/12 (2006.01); G02B 6/122 (2006.01)
CPC G02B 6/12004 (2013.01) [G02B 6/1228 (2013.01); G02B 2006/12097 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An optical system, comprising:
a slab waveguide, comprising:
a free propagation region; and
an output side; and
an output waveguide defined in the slab waveguide, comprising:
a waveguide core through which light propagates and including a first side and a second side opposite the first side;
a first light confining region adjacent to the first side of the waveguide core; and
a second light confining region adjacent to the second side of the waveguide core, wherein:
the output waveguide terminates before the output side of the slab waveguide and before the free propagation region;
the light exits the waveguide core into the free propagation region; and
the light exits the free propagation region at the output side, thereby reducing back reflections into the output waveguide.