Optical display system having optical waveguides for guiding polarized lights and method, and display device having the same

Patent metadata

Field	Value
Publication number	US-11719935-B2
Application number	US-201916957589-A
Country	US
Kind code	B2
Filing date	Aug 26, 2019
Priority date	Aug 26, 2019
Publication date	Aug 8, 2023
Grant date	Aug 8, 2023

Abstract

The present disclosure provides an optical display system and method, and a display device. The optical display system includes: a display screen; a light split member configured to split light from the display screen into a first polarized light and a second polarized light with different polarization directions; a first optical waveguide configured to guide the first polarized light to a light exit side of the optical display system; and a second optical waveguide located at a light exit side of the first optical waveguide, spaced apart from the first optical waveguide, and configured to at least partially transmit the first polarized light and guide the second polarized light to the light exit side of the optical display system.

First claim

What is claimed is:

1. An optical display system, comprising:
a display screen;
a light split member configured to split light from the display screen into a first polarized light and a second polarized light with different polarization directions;
a first optical waveguide configured to guide the first polarized light to a light exit side of the optical display system;
a second optical waveguide located at a light exit side of the first optical waveguide, spaced apart from the first optical waveguide, and configured to at least partially transmit the first polarized light and guide the second polarized light to the light exit side of the optical display system, comprising:
a second optical waveguide body configured to make the second polarized light propagate by total reflection in the second optical waveguide body, and
a polarizing member disposed in the second optical waveguide body and comprising a curved polarizing reflective film configured to totally reflect the second polarized light and totally transmit the first polarized light and

a fifth lens assembly disposed between the display screen and the light split member,
wherein the fifth lens assembly is configured to control an optical power of the first polarized light, and the fifth lens assembly and the polarizing member are configured to control an optical power of the second polarized light, so that imaging screens during imaging with the first polarized light and the second polarized light respectively by the optical display system are at different virtual image planes.

2. The optical display system according to claim 1 , wherein the first optical waveguide comprises:
a first optical waveguide body configured to make the first polarized light propagate by total reflection in the first optical waveguide body; and
a transflective member disposed in the first optical waveguide body and configured to partially reflect the first polarized light and partially transmit the first polarized light.

3. The optical display system according to claim 2 , wherein the transflective member comprises a plurality of transflective films parallel to and spaced apart from each other.

4. The optical display system according to claim 1 , further comprising:
a first light valve disposed between the light split member and the first optical waveguide and configured to transmit the first polarized light in a case where the display screen displays a distant view screen, and not transmit the first polarized light in a case where the display screen displays a near view screen; and
a second light valve disposed between the light split member and the second optical waveguide and configured to transmit the second polarized light in the case where the display screen displays the near view screen, and not transmit the second polarized light in the case where the display screen displays the distant view screen.

5. The optical display system according to claim 4 , wherein at least one of the first light valve or the second light valve comprises a liquid crystal light valve.

6. The optical display system according to claim 1 , further comprising:
a first lens assembly of a first focal length disposed between the light split member and the first optical waveguide; and
a second lens assembly of a second focal length different from the first focal length disposed between the light split member and the second optical waveguide.

7. The optical display system according to claim 1 , further comprising:
a fourth lens assembly disposed between the light split member and the second optical waveguide.

8. The optical display system according to claim 1 , further comprising:
a lens of variable focal length disposed at a light exit side of the second optical waveguide.

9. The optical display system according to claim 8 , wherein the lens of variable focal length comprises a liquid crystal lens.

10. The optical display system according to claim 1 , wherein the light split member comprises:
a polarizing reflective sheet configured to split the light from the display screen into the first polarized light and the second polarized light;
a first reflective member configured to reflect the first polarized light from the polarizing reflective sheet to the first optical waveguide; and
a second reflective member configured to reflect the second polarized light from the polarizing reflective sheet the second optical waveguide.

11. A display device, comprising: the optical display system according to claim 1 .

12. An optical display method of an optical display system comprising a display screen, a light split member, a first optical waveguide, a second optical waveguide located at a light exit side of the first optical waveguide and spaced apart from the first optical waveguide, and a fifth lens assembly disposed between the display screen and the light split member, the second optical waveguide comprising a second optical waveguide body and a polarizing member comprising a curved polarizing reflective film, the optical display method comprising:
displaying, by the display screen, a near view screen and a distant view screen alternately;
splitting, by the light split member, light from the display screen into a first polarized light and a second polarized light with different polarization directions;
guiding, by the first optical waveguide, the first polarized light to a light exit side of the optical display system, in a case where the display screen displays the distant view screen, wherein the first polarized light is totally transmitted by the curved polarizing reflective film of the second optical waveguide; and
guiding, by the second optical waveguide, the second polarized light to the light exit side of the optical display system, in a case where the display screen displays the near view screen, wherein the second polarized light propagates by total reflection in the second optical waveguide body, and the second polarized light is totally reflected by the curved polarizing reflective film,
wherein an optical power of the first polarized light is controlled by the fifth lens assembly, and an optical power of the second polarized light is controlled by the fifth lens assembly and the polarizing member, so that imaging screens during imaging with the first polarized light and the second polarized light respectively by the optical display system are at different virtual image planes.

13. The optical display method according to claim 12 , wherein:
the optical display system comprises a first light valve disposed between the light split member and the first optical waveguide, and a second light valve disposed between the light split member and the second optical waveguide; and
the optical display method further comprises:
controlling the first light valve to open to transmit the first polarized light, and the second light valve to close to not transmit the second polarized light, in the case where the display screen displays the distant view screen, and
controlling the first light valve to close to not transmit the first polarized light, and the second light valve to open to transmit the second polarized light, in the case where the display screen displays the near view screen.

14. The optical display method according to claim 12 , wherein:
the optical display system comprises a lens of variable focal length located at a light exit side of the second optical waveguide; and
the optical display method further comprises:
adjusting the lens of variable focal length to be of a first focal length to make the first polarized light present a distant view imaging screen with a first virtual image distance

Assignees

• Beijing Boe Optoelectronics Tech Co Ltd
• Boe Technology Group Co Ltd

Inventors

• Dong Ruijun
• Wang Chenru
• Liu Yali
• Li Ke
• Zhang Hao

Classifications

• G02B27/0172 Primary

  characterised by optical features · CPC title

• G02B27/283

  used for beam splitting or combining · CPC title

• G02B27/286

  for controlling or changing the state of polarisation, e.g. transforming one polarisation state into another (G02B5/3083 takes precedence; light guide coupling means utilising polarising elements G02B6/34) · CPC title

• G02B30/25

  using polarisation techniques · CPC title

• G02B2027/0127

  comprising devices increasing the depth of field · CPC title