US 12,001,168 B2
Holographic projectors including size correction and alignment of beams having different wavelengths of light
Kai-Han Chang, Madison Heights, MI (US); and Thomas A. Seder, Fraser, MI (US)
Assigned to GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed by GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed on Sep. 30, 2020, as Appl. No. 17/038,356.
Prior Publication US 2022/0100147 A1, Mar. 31, 2022
Int. Cl. G03H 1/22 (2006.01); G02B 27/01 (2006.01)
CPC G03H 1/2294 (2013.01) [G02B 27/0172 (2013.01); G03H 1/2249 (2013.01); G02B 2027/0174 (2013.01); G02B 2027/0178 (2013.01); G03H 2001/2271 (2013.01); G03H 2222/34 (2013.01); G03H 2223/18 (2013.01); G03H 2223/19 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A holographic projection system comprising:
a first light source configured to generate a first light beam;
a second light source configured to generate a second light beam;
a third light source configured to generate a third light beam, wherein the first light beam, the second light beam and the third light beam have respective wavelengths;
a plurality of spatial light modulators configured to respectively diffract the first light beam, the second light beam and the third light beam;
a first lens disposed to adjust a divergence angle of one of the first light beam, the second light beam or the third light beam, such that diffracted light out of each of the plurality of spatial light modulators is at a same diffraction angle, wherein the first lens adjusts the divergence angle of the one of the first light beam, the second light beam and the third light beam prior to being received at one of the plurality of spatial light modulators, and
wherein the plurality of spatial light modulators are configured to encode phase holograms including respective versions of a graphic image based on light generated by the first light source, the second light source and the third light source including light output from the first lens to provide phase hologram beams;
a combiner configured to combine the phase hologram beams to provide a combined phase hologram beam projected for viewing a combined graphic image; and
a control module configured to encode a prism hologram on one of the plurality of spatial light modulators to align outputs of the plurality of spatial light modulators.