US 12,416,899 B2
Optically addressable pixelated spatial light modulator and spatial light field modulation method
Hui Gao, Wuhan (CN); Ke Xu, Wuhan (CN); Wei Xiong, Wuhan (CN); Xuhao Fan, Wuhan (CN); and Xinger Wang, Wuhan (CN)
Assigned to Huazhong University of Science and Technology, Wuhan (CN); and OPTICS VALLEY LABORATORY, Wuhan (CN)
Filed by Huazhong University of Science and Technology, Wuhan (CN); and OPTICS VALLEY LABORATORY, Wuhan (CN)
Filed on Dec. 26, 2024, as Appl. No. 19/002,669.
Claims priority of application No. 2023118477955 (CN), filed on Dec. 29, 2023.
Prior Publication US 2025/0123592 A1, Apr. 17, 2025
Int. Cl. G03H 1/22 (2006.01)
CPC G03H 1/2286 (2013.01) [G03H 1/2202 (2013.01); G03H 1/2294 (2013.01); G03H 2222/12 (2013.01); G03H 2223/24 (2013.01); G03H 2223/50 (2013.01); G03H 2225/30 (2013.01)] 5 Claims
OG exemplary drawing
 
1. An optically addressable pixelated spatial light modulator, comprising:
a laser light source, a structured light field encoding projection module, and a superpixel metasurface device;
wherein the structured light field encoding projection module comprises a structured light field encoding module, and the structured light field encoding module is configured to encode a laser beam emitted by the laser light source into a structured light beam according to a modulation amount distribution of a target light field;
the superpixel metasurface device comprises a plurality of unit cell structures, each unit cell structure serving as a light field modulation pixel point; each unit cell structure comprises a plurality of sub-wavelength micro-nano structures, and the unit cell structure is configured to generate a light field modulation amount under an action of the structured light beam for a light field modulation; the light field modulation comprises phase modulation and/or amplitude modulation; the sub-wavelength micro-nano structures are isotropic structures or anisotropic structures;
wherein the sub-wavelength micro-nano structures having different morphological structures are arranged within each unit cell structure; the sub-wavelength micro-nano structures tiled within the unit cell structure are configured to achieve different light field modulations at each pixel location;
wherein the structured light field encoding module is configured to determine selection information for the unit cell structures based on the modulation amount distribution of the target light field, and to encode the laser beam into the structured light beam according to the selection information;
the structured light beam is incident on the superpixel metasurface device, selecting one or more sub-wavelength micro-nano structures in the unit cell structure corresponding to the modulation amount distribution to achieve the target light field modulation;
and wherein:
(i) each unit cell structure comprises four sub-wavelength micro-nano structures individually providing fourth-order phase modulation amounts ϕn, wherein the fourth-order phase modulation amounts ϕn are 0, π/2, π, 3π/2, respectively, where n=1 to 4; or
(ii) each unit cell structure comprises nine sub-wavelength micro-nano structures individually providing ninth-order phase modulation amounts ϕn, wherein the ninth-order phase modulation amounts ϕn are 0, 2π/9, 4π/9, 2π/3, 8π/9, 10π/9, 4π/3, 14π/9, 16π/9, respectively, where n=1 to 9; a light field modulation amount generated by a single unit cell structure through combination of sub-wavelength micro-nano structures is represented as

OG Complex Work Unit Math
fneiϕn, where fn is 0 or 1, indicating whether a corresponding sub-wavelength micro-nano structure within the unit cell structure is unselected or selected.