Patent ID: 11860573
Assignee: META PLATFORMS TECHNOLOGIES, LLC
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 11:
12. A method, comprising:
directing an input beam to a polarization volume hologram (“PVH”) mask;
forwardly diffracting, by the PVH mask, the input beam as a first set of two collimated circularly polarized beams having a same handedness, wherein the two collimated circularly polarized beams in the first set output from the PVH mask have a zero diffraction angle and a non-zero diffraction angle, respectively, and have non-parallel propagation directions; and
converting, by a polarization conversion element, the first set of two collimated circularly polarized beams into a second set of two collimated circularly polarized beams having opposite handednesses, wherein when the two collimated circularly polarized beams in the second set are output from the polarization conversion element, the two collimated circularly polarized beams in the second set interfere with one another to generate a polarization interference pattern.