US 12,405,482 B2
Achromatic holographic phase masks
Leonid Glebov, Oviedo, FL (US); Ivan Divliansky, Orlando, FL (US); Oussama Mhibik, Oviedo, FL (US); and Vadim Smirnov, Orlando, FL (US)
Assigned to IPG PHOTONICS CORPORATION, Malborough, MA (US)
Appl. No. 17/796,705
Filed by IPG PHOTONICS CORPORATION, Oxford, MA (US)
PCT Filed Feb. 4, 2021, PCT No. PCT/US2021/016588
§ 371(c)(1), (2) Date Aug. 1, 2022,
PCT Pub. No. WO2021/158774, PCT Pub. Date Aug. 12, 2021.
Claims priority of provisional application 62/970,001, filed on Feb. 4, 2020.
Prior Publication US 2023/0062015 A1, Mar. 2, 2023
Int. Cl. G03H 1/02 (2006.01); G02B 27/42 (2006.01); G03H 1/10 (2006.01); G11B 7/1353 (2012.01); G11B 7/1395 (2012.01)
CPC G02B 27/4277 (2013.01) [G03H 1/0248 (2013.01); G03H 1/10 (2013.01); G11B 7/1353 (2013.01); G03H 2001/0216 (2013.01); G03H 2223/13 (2013.01); G11B 7/1395 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method, comprising:
selecting a period for a volume Bragg grating (VBG) such that a spectral selectivity of the VBG is at least as wide as a spectral width of a broadband light beam that is to be spatially transformed;
selecting a desired beam transformation for the broadband light beam;
passing a first light beam from a recording light source through an optical device to a volume holographic recording medium, the recording light source emitting light at a recording wavelength that is within a photosensitivity spectrum of the volume holographic recording medium, and the optical device configured to induce the desired beam transformation;
directing a second light beam from the recording light source to the volume holographic recording medium; and
converging the first light beam and the second beam at a recording angle such that:
a spatial refractive index modulation profile is recorded in the volume holographic recording medium that provides the VBG with the selected period, and
a phase profile is embedded in the VBG that induces the desired beam transformation for each spectral component within a spectral width of the VBG.