DISPLAY DEVICE

• US 20170285359A1
• Filed: 03/28/2017
• Published: 10/05/2017
• Est. Priority Date: 03/31/2016
• Status: Active Grant

• Current Assignee: Japan Display Incorporated
• Original Assignee: Japan Display Incorporated
• Inventors: Numata, Yudai, Koito, Takeo
• Granted Patent: US 9,989,776 B2
• Time in Patent Office: Days
• CPC Class Codes: G02B 30/25 using polarisation techniques
• CPC Class Codes: G02B 30/56 by projecting aerial or floating images
• CPC Class Codes: G02B 5/124 plural reflecting elements forming part of a unitary plate or sheet
• CPC Class Codes: G02B 5/3058 comprising electrically conductive elements, e.g. wire grids, conductive particles
• CPC Class Codes: G02B 5/3083 Birefringent or phase retarding elements G02B5/3008, G02B5/3016 take precedence; systems for polarisation control G02B27/286; manufacturing phase modulating patterns by lithographic processes G03F7/001

Abstract

According to one embodiment, a display device includes a display module which emits display light, a polarizing element including a transmission axis which transmits first linearly polarized light, the polarizing element reflecting second linearly polarized light intersecting the transmission axis, and an optical element includes a retroreflector which retroreflects light reflected from the polarizing element, the optical element being curved, and includes a first portion which is concave, and a second portion which is convex and is connected to the first portion.

Claims

1. A display device comprising:

a display module which emits display light;

a polarizing element including a transmission axis which transmits first linearly polarized light, the polarizing element reflecting second linearly polarized light intersecting the transmission axis; and

an optical element comprising a retroreflector which retroreflects light reflected from the polarizing element,

the optical element being curved, and comprising a first portion which is concave, and a second portion which is convex and is connected to the first portion.

2. The display device of claim 1, wherein the first portion is closer to the display module than the second portion is.

3. The display device of claim 2, wherein:

the optical element includes a first end portion and a second end portion;

the first end portion is closer to the display module than the second end portion is; and

when a length from the first end portion to the second end portion in a first direction is defined as L, a length from the first end portion to a connection part of the first portion and the second portion in the first direction is greater than L/2.

4. The display device of claim 3, wherein:

a first distance from the first end portion to the polarizing element in a second direction is greater than a second distance from the second end portion to the polarizing element in the second direction; and

a third distance from the connection part to the polarizing element in the second direction is less than the first distance, and is greater than the second distance.

5. The display device of claim 1, wherein:

the retroreflector comprises a triangular edge in planar view; and

a connection part of the first portion and the second portion extends in a direction parallel to one side of the edge.

6. The display device of claim 1, wherein each of the first portion and the second portion is a curved surface.

7. The display device of claim 1, further comprising a retardation film which imparts a phase difference to transmitted light, wherein

the retardation film is disposed along an inner surface of the polarizing element.

8. A display device comprising:

a display module which emits display light;

a polarizing element including a transmission axis which transmits first linearly polarized light, the polarizing element reflecting second linearly polarized light intersecting the transmission axis; and

an optical element comprising a retroreflector which retroreflects light reflected from the polarizing element,

the optical element comprising a first portion and a second portion,

the first portion being a concave surface recessed toward a side separated from the polarizing element,

the second portion being a convex surface projected toward a side closer to the polarizing element,

the first portion being closer to the display module than the second portion is.

9. The display device of claim 8, wherein:

the optical element includes a first end portion and a second end portion;

the first end portion is closer to the display module than the second end portion is; and

when a length from the first end portion to the second end portion in a first direction is defined as L, a length from the first end portion to a connection part of the first portion and the second portion in the first direction is greater than L/2.

10. The display device of claim 9, wherein:

a first distance from the first end portion to the polarizing element in a second direction is greater than a second distance from the second end portion to the polarizing element in the second direction; and

a third distance from the connection part to the polarizing element in the second direction is less than the first distance, and is greater than the second distance.

11. The display device of claim 8, wherein:

the retroreflector comprises a triangular edge in planar view; and

a connection part of the first portion and the second portion extends in a direction parallel to one side of the edge.

12. The display device of claim 8, further comprising a retardation film which imparts a phase difference to transmitted light, wherein

the retardation film is disposed along an inner surface of the polarizing element.

13. A display device comprising:

a display module which emits display light;

a polarizing element including a transmission axis which transmits first linearly polarized light, the polarizing element reflecting second linearly polarized light intersecting the transmission axis; and

an optical element comprising a retroreflector which retroreflects light reflected from the polarizing element,

the optical element including a first end portion, a second end portion, a first portion, a second portion, and a connection part connecting the first portion and the second portion,

the first portion being located between the first end portion and the connection part, and having a concave shape recessed toward a side that is more separated from the display module and the polarizing element than a surface connecting the first end portion and the connection part,

the second portion being located between the connection part and the second end portion, and having a convex shape projected toward a side that is closer to the display module and the polarizing element than a surface connecting the connection part and the second end portion.

14. The display device of claim 13, wherein the first portion is closer to the display module than the second portion is.

15. The display device of claim 13, wherein when a length from the first end portion to the second end portion in a first direction is defined as L, a length from the first end portion to the connection part in the first direction is greater than L/2.

16. The display device of claim 13, wherein:

a first distance from the first end portion to the polarizing element in a second direction is greater than a second distance from the second end portion to the polarizing element in the second direction; and

a third distance from the connection part to the polarizing element in the second direction is less than the first distance, and is greater than the second distance.

17. The display device of claim 13, wherein:

the retroreflector comprises a triangular edge in planar view; and

the connection part extends in a direction parallel to one side of the edge.

18. The display device of claim 13, wherein each of the first portion and the second portion is a curved surface.

19. The display device of claim 13, further comprising a retardation film which imparts a phase difference to transmitted light, wherein

the retardation film is disposed along an inner surface of the polarizing element.