US 11,994,689 B2
Diffractive optical elements for large-field image display
Khoa Nguyen, Sunnyvale, CA (US)
Assigned to GOOGLE LLC, Mountain View, CA (US)
Appl. No. 15/733,635
Filed by GOOGLE LLC, Mountain View, CA (US)
PCT Filed Oct. 18, 2019, PCT No. PCT/US2019/056928
§ 371(c)(1), (2) Date Sep. 22, 2020,
PCT Pub. No. WO2021/076148, PCT Pub. Date Apr. 22, 2021.
Prior Publication US 2021/0325688 A1, Oct. 21, 2021
Int. Cl. G02B 27/42 (2006.01); G02B 5/18 (2006.01); G02B 27/10 (2006.01)
CPC G02B 27/4272 (2013.01) [G02B 5/1823 (2013.01); G02B 27/10 (2013.01); G02B 27/4205 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method, comprising:
generating a wavefront modulating element (WME) based on a first image, the WME including a plurality of WME segments, each of the plurality of WME segments corresponding to a respective portion of the first image;
generating, by an illumination system, a beam of electromagnetic radiation; and
illuminating each of the plurality of WME segments with the beam of electromagnetic radiation at a specified angle of incidence, each of the plurality of WME segments being disposed upon a respective diffraction grating to produce a respective monolithic diffractive stack for that WME segment, the plurality of WME segments producing upon illumination a second image, a difference between the first image and the second image being less than a specified threshold.