US 11,656,500 B2
Switchable multilayer cholesteric liquid crystal reflective polarizer
Yuge Huang, Redmond, WA (US); Fenglin Peng, Redmond, WA (US); Lu Lu, Kirkland, WA (US); and Junren Wang, Redmond, WA (US)
Assigned to META PLATFORMS TECHNOLOGIES, LLC, Menlo Park, CA (US)
Filed by META PLATFORMS TECHNOLOGIES, LLC, Menlo Park, CA (US)
Filed on Jun. 10, 2020, as Appl. No. 16/898,091.
Prior Publication US 2021/0389621 A1, Dec. 16, 2021
Int. Cl. G02F 1/13357 (2006.01); G02F 1/1335 (2006.01); G02B 5/30 (2006.01)
CPC G02F 1/13362 (2013.01) [G02B 5/3016 (2013.01); G02F 1/133526 (2013.01); G02F 1/133543 (2021.01); G02F 2201/343 (2013.01)] 18 Claims
OG exemplary drawing
 
1. An optical device, comprising:
a light source;
a polarization selective optical element including a stack of a plurality of cholesteric liquid crystal layers, the plurality of cholesteric liquid crystal layers including a first cholesteric liquid crystal layer with liquid crystal molecules arranged in a first helical configuration having a first pitch range for light of a first wavelength range and a second cholesteric liquid crystal layer with liquid crystal molecules arranged in a second helical configuration having a second pitch range for light of a second wavelength range that is different from the first wavelength range;
a partial reflector located between the light source and the polarization selective optical element;
a first lens positioned between the polarization selective optical element and the partial reflector; and
a second lens positioned relative to the polarization selective optical element so that the polarization selective optical element is positioned between the second lens and the partial reflector.