公开(公告)号：WO2021076243A1

公开(公告)日：2021-04-22

申请号：PCT/US2020/049611

申请日：2020-09-06

Applicant: FACEBOOK TECHNOLOGIES, LLC

Inventor： JIANG, Yingfei ,  JAMALI, Afsoon ,  JANG, Changwon ,  TRAVIS, Adrian ,  MAIMONE, Andrew ,  LU, Lu

IPC: G02B5/18 ,  G02B27/01 ,  C09K19/02

Abstract: An optical device is provided. The optical device includes an optical grating. The optical grating includes two electrodes arranged opposite to each other and a liquid crystal (LC) composition sandwiched between the electrodes. The two electrodes provide a driving voltage to the optical grating. The LC mixture includes a host LC and one or more LC dimers dissolved as a guest in the host LC. The host LC and the one or more LC dimers have respective dielectric anisotropies of opposite signs in nematic phase. A net dielectric anisotropy of the LC mixture is substantially neutral at a predetermined temperature.

公开(公告)号：WO2021076244A1

公开(公告)日：2021-04-22

申请号：PCT/US2020/049618

申请日：2020-09-07

Applicant: FACEBOOK TECHNOLOGIES, LLC

Inventor： JIANG, Yingfei ,  JAMALI, Afsoon ,  JANG, Changwon ,  TRAVIS, Adrian ,  MAIMONE, Andrew ,  LU, Lu

IPC: C09K19/04 ,  C09K19/02

Abstract: A liquid crystal (LC) mixture for a pitch variable optical element is provided. The LC mixture includes a host LC and one or more LC dimers dissolved as a guest in the host LC. The host LC and the one or more LC dimers have respective dielectric anisotropies of opposite signs in nematic phase. A net dielectric anisotropy of the LC mixture is substantially neutral.

公开(公告)号：WO2020236769A1

公开(公告)日：2020-11-26

申请号：PCT/US2020/033515

申请日：2020-05-19

Applicant: FACEBOOK TECHNOLOGIES, LLC

Inventor： GENG, Ying ,  TRAVIS, Adrian ,  LI, Gang

IPC: G02B27/01 ,  G02B27/42 ,  F21V8/00

Abstract: A device for illuminating a spatial light modulator includes a light source and an optical element. The light source is configured to provide illumination light. The optical element has a first surface, a second surface that is distinct from and non-parallel to the first surface, and a third surface that is distinct from and non-parallel to the first surface and the second surface. The optical element is configured to receive the illumination light at the first surface, propagate the illumination light via total internal reflection, and output the illumination light from the third surface. Also disclosed is a method performed by the device.