US 12,292,579 B2
Method and system for generating polarized propagation-invariant light field
Yahong Chen, Suzhou (CN); Zhen Dong, Suzhou (CN); Xi Sun, Suzhou (CN); Fei Wang, Suzhou (CN); and Yangjian Cai, Suzhou (CN)
Assigned to SOOCHOW UNIVERSITY, Suzhou (CN)
Appl. No. 17/800,206
Filed by SOOCHOW UNIVERSITY, Suzhou (CN)
PCT Filed Dec. 27, 2021, PCT No. PCT/CN2021/141554
§ 371(c)(1), (2) Date Aug. 16, 2022,
PCT Pub. No. WO2023/103112, PCT Pub. Date Jun. 15, 2023.
Claims priority of application No. 202111481793.X (CN), filed on Dec. 7, 2021.
Prior Publication US 2023/0314822 A1, Oct. 5, 2023
Int. Cl. G02B 27/09 (2006.01); G02B 5/30 (2006.01); G02B 5/32 (2006.01); G02B 27/10 (2006.01)
CPC G02B 27/0916 (2013.01) [G02B 5/3083 (2013.01); G02B 5/32 (2013.01); G02B 27/0955 (2013.01); G02B 27/1093 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A system for generating a polarized propagation-invariant light field, comprising:
a laser source and a spatial light modulator, wherein the laser source is configured to generate laser light to enter the spatial light modulator;
a computer, configured to: generate two holograms, superimpose grating functions of the two holograms to obtain a composite hologram, and load the composite hologram into the spatial light modulator, wherein the spatial light modulator is configured to modulate the laser light and simultaneously generate a first Laguerre-Gaussian mode beam and a second Laguerre-Gaussian mode beam, and the first Laguerre-Gaussian mode beam and the second Laguerre-Gaussian mode beam satisfy:
2p1+|l1|=2p2+|l2|,
wherein p1 and p2 respectively represent radial indices of the first Laguerre-Gaussian mode beam and the second Laguerre-Gaussian mode beam, and l1 and l2 respectively represent topological charges of the first Laguerre-Gaussian mode beam and the second Laguerre-Gaussian mode beam;
a first lens, configured to collimate the first Laguerre-Gaussian mode beam and the second Laguerre-Gaussian mode beam;
a shading element, configured to simultaneously filter out a positive first-order diffracted beam and a negative first-order diffracted beam of the first Laguerre-Gaussian mode beam and the second Laguerre-Gaussian mode beam after the collimation;
a first quarter-wave plate and a second quarter-wave plate, configured to modulate polarization states of the first Laguerre-Gaussian mode beam and the second Laguerre-Gaussian mode beam after filtering from linear polarization to right-handed circular polarization and left-handed circular polarization orthogonal to each other;
a second lens, configured to focus the first Laguerre-Gaussian mode beam and the second Laguerre-Gaussian mode beam with the polarization states being circular polarization; and
a beam combining element, configured to: combine the focused first Laguerre-Gaussian mode beam and second Laguerre-Gaussian mode beam into one beam, and generate a plurality of diffracted beams, to obtain a polarized propagation-invariant light field.