One-way circularly polarized light generated by propagation through Ch-GLC films doped with light-absorbing dyes

Patent metadata

Field	Value
Publication number	US-12461297-B2
Application number	US-202217581124-A
Country	US
Kind code	B2
Filing date	Jan 21, 2022
Priority date	Feb 19, 2021
Publication date	Nov 4, 2025
Grant date	Nov 4, 2025

Abstract

An optical system that includes a cholesteric glassy liquid crystal film doped with a dye and configured to preferentially absorb light of a first handedness, such as left-hand circularly polarized (LCP) light, but pass light of the opposite handedness, such a right-hand circularly polarized (RCP) light. Adding an anti-reflection coating can further increase the transmission-to-reflection ratio.

First claim

The invention claimed is:

1 . An optical device comprising:
a cholesteric glassy liquid crystal film doped with a dye, wherein said film:
preferentially absorbs a forward component of light incident on the film that is circularly polarized with handedness in a first direction as well as any backward component of the incident light that is circularly polarized with handedness in said first direction and has been reflected after passage through the doped film; and
preferentially passes through the doped film a forward component of the incident light that is circularly polarized with handedness in a second direction that is different from the first direction.

2 . The optical device of claim 1 , in which the film has absorption and stop band ranges that overlap in wavelength.

3 . The optical device of claim 2 , in which the film is doped with a positive or negative dichroic dye.

4 . The optical device of claim 3 that also includes an anti-reflective coating on the device configured to further reduce reflected light.

5 . The optical device of claim 4 , in which an isolation ratio of the optical device is in a range of 10 to 500.

6 . The optical device of claim 3 , in which an isolation ratio of the optical device is in a range of 10 to 500.

7 . The optical device of claim 1 , in which the film has absorption and stop band ranges spaced from each other in wavelength.

8 . The optical device of claim 7 , in which the absorption band is at a shorter wavelength range than the stop band.

9 . The optical device of claim 7 , in which the absorption band is at a longer wavelength range than the stop band.

10 . The optical device of claim 1 , in which the film comprises a monodomain cholesteric liquid crystal.

11 . The optical device of claim 10 , in which the film is doped with a dye configured to preferentially absorb components of incident light depending on handedness of said components.

12 . The optical device of claim 11 that also includes an anti-reflective coating to further reduce incident light reflected by the device.

13 . The optical device of claim 12 , in which an isolation ratio of the optical device is in a range of 10 to 500.

14 . The optical device of claim 11 , in which an isolation ratio of the optical device is in a range of 10 to 500.

15 . The optical device of claim 1 that further includes a receiving surface at a first side of said film, receiving light passed by said film, wherein said film preferentially absorbs light reflected by said first surface that is circularly polarized with handedness in said first direction.

16 . The optical device of claim 15 , in which the film has absorption and stop band ranges that overlap in wavelength.

17 . The optical device of claim 16 , in which the film is doped with a linear dichroic dye represented by

18 . The optical device of claim 17 , in which an isolation ratio of the optical device is in a range of 10 to 500.

19 . The optical device of claim 15 , in which an isolation ratio of the optical device is in a range of 10 to 500.

20 . The optical device of claim 15 , in which the film has absorption and stop band ranges spaced from each other in wavelength.

21 . The optical device of claim 20 , in which the absorption band is at a shorter wavelength range than the stop band.

22 . The optical device of claim 21 , in which the absorption band is at a longer wavelength range than the stop band.

23 . The optical device of claim 15 , in which the film comprises a monodomain cholesteric liquid crystal.

24 . The optical device of claim 23 that also includes an anti-reflective coating to further reduce reflected light.

25 . The optical device of claim 24 , in which an isolation ratio of the optical device is in a range of 10 to 500.

26 . The optical device of claim 1 , in which the liquid crystal film comprises a glassy chiral-nematic liquid crystal composition comprising a compound having a 1, 3, 5-benzenetricarbonyl central moiety, said composition being characterized by a morphologically stable cholesteric phase and said compound having the structural formula

wherein each N represents a nematic group connected to said central moiety by a carboxylic ester linkage and Ch represents a chiral group connected to said central moiety by a carboxylic ester linkage, and variations thereof are identified in the claims of the patent and the remainder of the patent specification.

Assignees

• Univ Rochester

Inventors

• Chen Shaw
• Anthamatten Mitchell
• Ou Jane

Classifications

• G02B5/003

  Light absorbing elements · CPC title

• C09B1/5035

  only amino and hydroxy groups · CPC title

• C09K19/603 Primary

  Anthroquinonic · CPC title

• C09K19/36

  Steroidal liquid crystal compounds · CPC title

• C09B1/42

  the acyl groups being residues of an aromatic carboxylic acid · CPC title