US 11,733,565 B2
Liquid crystal display with external retarder
Nicholas William Melena, Phoenix, AZ (US); and Terry James Scheffer, Hilo, HI (US)
Assigned to Snap Inc., Santa Monica, CA (US)
Appl. No. 17/297,811
Filed by Snap Inc., Santa Monica, CA (US)
PCT Filed Dec. 7, 2019, PCT No. PCT/US2019/065114
§ 371(c)(1), (2) Date May 27, 2021,
PCT Pub. No. WO2020/146072, PCT Pub. Date Jul. 16, 2020.
Claims priority of provisional application 62/776,794, filed on Dec. 7, 2018.
Prior Publication US 2022/0050332 A1, Feb. 17, 2022
Int. Cl. G02F 1/13363 (2006.01); G02F 1/1335 (2006.01); G02F 1/1362 (2006.01)
CPC G02F 1/133638 (2021.01) [G02F 1/13363 (2013.01); G02F 1/133531 (2021.01); G02F 1/136277 (2013.01); G02F 2413/05 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A display system, comprising:
a spatial light modulator comprising a first substrate, a second substrate, and a liquid crystal layer between the first substrate and the second substrate, wherein the spatial light modulator is characterized by a first retardation and a first phase retardation, wherein the spatial light modulator has a first slow axis for light propagation; and
a retarder that is positioned external to the spatial light modulator, wherein the retarder is characterized by a second retardation and a second phase retardation, the retarder comprising a second slow axis for light propagation that is perpendicular to the first slow axis, wherein the second retardation has a value such that the retarder has a phase retardation value above 0.25 for all illumination wavelengths in a set of illumination wavelengths, wherein the set of illumination wavelengths includes at least one illumination wavelength in each of at least three different color spectrums, and wherein the display system is an LCoS display that operates in at least one of a VAN mode and a TVAN mode.