US 12,332,442 B2
High efficiency optical assembly with folded optical path
Gang Li, Bothell, WA (US); Brian Wheelwright, Sammamish, WA (US); Andrew Maimone, Duvall, WA (US); Yang Zhao, Kirkland, WA (US); Ying Geng, Bellevue, WA (US); and Douglas Robert Lanman, Bellevue, WA (US)
Assigned to Meta Platforms Technologies, LLC, Menlo Park, CA (US)
Filed by META PLATFORMS TECHNOLOGIES, LLC, Menlo Park, CA (US)
Filed on Dec. 1, 2021, as Appl. No. 17/540,049.
Prior Publication US 2023/0168506 A1, Jun. 1, 2023
Int. Cl. G02B 27/01 (2006.01)
CPC G02B 27/0172 (2013.01) [G02B 2027/0174 (2013.01); G02B 2027/0178 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A display device, comprising:
a display module for providing first image light;
a first optical element positioned relative to the display module for receiving the first image light from the display module and transmitting the first image light, wherein the display module includes at least a first region from which the first image light is provided in one or more directions other than a direction perpendicular to the first optical element; and
a second optical element separate from and positioned relative to the first optical element so that the second optical element receives the first image light transmitted through the first optical element and sends the received first image light back toward the first optical element as second image light, the first optical element receives the second image light from the second optical element and sends the second image light back toward the second optical element, and the second optical element receives and transmits the second image light from the first optical element, wherein the display module foregoes providing light in a direction perpendicular to the first optical element.