Beam deflector and three-dimensional display device including the same

Patent metadata

Field	Value
Publication number	US-11262614-B2
Application number	US-202016883596-A
Country	US
Kind code	B2
Filing date	May 26, 2020
Priority date	Oct 18, 2017
Publication date	Mar 1, 2022
Grant date	Mar 1, 2022

Abstract

A beam deflector includes a first wavelength selective polarizer configured to convert a polarization state of light in a first wavelength band into a first polarization state, a first liquid crystal deflector including liquid crystal molecules and an optical path change surface to deflect light incident from the first wavelength selective polarizer, and a controller configured to control the first liquid crystal deflector to adjust an angle of the first optical path change surface.

First claim

What is claimed is:

1. A display device comprising:
a polarizer that is configured to transmit light of a specific polarization state and absorb light of a polarization state that is different from the specific polarization state;
a first wavelength selective polarizer configured to selectively convert a second polarization state of light in a first wavelength band among light transmitted by the polarizer into a first polarization state and maintain a second polarization state of light in a second wavelength band that is different from the first wavelength band, the light transmitted by the polarizer being directly incident on the first wavelength selective polarizer; and
a first liquid crystal deflector configured to selectively deflect light of the first polarization state incident from the first wavelength selective polarizer, the first liquid crystal deflector comprising liquid crystal molecules, and a first electrode part and a second electrode part spaced apart from each other with the liquid crystal molecules therebetween.

2. The display device of claim 1 , wherein major axes of the liquid crystal molecules are arranged parallel to a direction of the first polarization state when a voltage is not applied to the first liquid crystal deflector.

3. The display device of claim 1 , wherein the first liquid crystal deflector further comprises a first optical path change surface, and
wherein an angle of inclination of the first optical path change surface is adjusted based on a voltage applied between the first electrode part and the second electrode part.

4. The display device of claim 3 , wherein the first electrode part comprises sub-electrodes configured such that voltages applied to the sub-electrodes are individually controlled.

5. The display device of claim 3 , further comprising a first-second liquid crystal deflector provided above the first liquid crystal deflector opposite to the first wavelength selective polarizer, the first-second liquid crystal deflector comprising liquid crystal molecules and a first-second optical path change surface,
wherein the angle of inclination of the first-second optical path change surface is adjusted with respect to a second axis which is different from a first axis of the first optical path change surface.

6. The display device of claim 3 , wherein a shape of the first optical path change surface is controlled such that the first optical path change surface comprises two surfaces inclined at different angles to deflect light incident on the first liquid crystal deflector in two directions, respectively, the two surfaces both deflecting light of the first wavelength band.

7. The display device of claim 3 , further comprising:
a second wavelength selective polarizer provided along an optical path of light passing through the first liquid crystal deflector and configured to convert the second polarization state of light in the second wavelength band into the first polarization state; and
a second liquid crystal deflector configured to deflect light incident from the second wavelength selective polarizer, the second liquid crystal deflector comprising liquid crystal molecules and a second optical path change surface.

8. The display device of claim 7 , further comprising:
a third wavelength selective polarizer provided along an optical path of light passing through the second liquid crystal deflector and configured to convert a polarization state of light in a third wavelength band into the first polarization state; and
a third liquid crystal deflector configured to deflect light incident from the third wavelength selective polarizer, the third liquid crystal deflector comprising liquid crystal molecules and a third optical path change surface.

9. The display device of claim 8 , wherein the first liquid crystal deflector, the second liquid crystal deflector, and the third liquid crystal deflector are controlled such that the first optical path change surface, the second optical path change surface, and the third optical path change surface are adjusted to be inclined at different angles to deflect light in the first wavelength band and the first polarization state, light in the second wavelength band and the first polarization state, and light in the third wavelength band and the first polarization state in a first direction, respectively.

10. The display device of claim 9 , further comprising an optical path change member configured to deflect the light deflected in the first direction by the first liquid crystal deflector, the second liquid crystal deflector, and the third liquid crystal deflector in a second direction different from the first direction.

11. The display device of claim 8 , wherein a shape of the first optical path change surface is controlled such that the first optical path change surface comprises two surfaces inclined at different angles to deflect light incident on the first liquid crystal deflector in two directions, respectively,
wherein a shape of the second optical path change surface is controlled such that the second optical path change surface has two surfaces inclined at different angles to deflect light incident on the second liquid crystal deflector in the two directions, respectively, and
wherein a shape of the third optical path change surface is controlled such that the third optical path change surface has two surfaces inclined at different angles to deflect light incident on the third liquid crystal deflector in the two directions, respectively.

12. The display device of claim 11 , further comprising an optical path change member configured to deflect the light deflected in the two directions by the first liquid crystal deflector, the second liquid crystal deflector, and the third liquid crystal deflector in directions different from the two directions.

13. The display device of claim 8 , further comprising:
a light source configured to emit a light beam comprising a plurality of wavelength bands; and
a spatial optical modulator configured to modulate light incident through the first liquid crystal deflector, the second liquid crystal deflector, and the third liquid crystal deflector.

14. The display device of claim 13 , wherein major axes of the liquid crystal molecules included in the first liquid crystal deflector, the second liquid crystal deflector, and the third liquid crystal deflector are arranged parallel to a direction of the first polarization state when a voltage is not applied to the first liquid crystal deflector, the second liquid crystal deflector, and the third liquid crystal deflector.

15. The display device of claim 13 , further comprising:
a first-second liquid crystal deflector provided above the first liquid crystal deflector, the first-second liquid crystal deflector comprising liquid crystal molecules and a first-second optical path change surface, wherein an angle of inclination of the first-second optical path change surface is adjusted with respect to a first-second axis which is different from a first axis of the first optical path change surface;
a second-second liquid crystal deflector provided above the second liquid crystal deflector, the second-second liquid crystal deflector comprising liquid crystal molecules and a second-second optical path change surface, wherein an angle of inclination of the second-second optical path change surface is adjusted with respect to a second-second axis which is different from a second axis of the second optical path change surface; and
a third-second liquid crystal deflector provided above the third liquid crystal deflector, the third-second liquid crystal deflector

Assignees

• Samsung Electronics Co Ltd

Inventors

• Won Kanghee
• Kim Young
• Song Hoon
• Kim Sunil
• An Jungkwuen
• Lee Sunghoon
• Lee Hongseok
• Choi Chilsung

Classifications

• G02B5/3033 Primary

  in the form of a thin sheet or foil, e.g. Polaroid · CPC title

• G03H2001/2242

  Multiple viewing windows · CPC title

• G03H2222/54

  Convergent beam · CPC title

• G03H2226/05

  Means for tracking the observer · CPC title

• G02F1/133533

  Colour selective polarisers (G02F1/1347 takes precedence) · CPC title