Visual display unit illumination

• US 8,149,353 B2
• Filed: 10/11/2002
• Issued: 04/03/2012
• Est. Priority Date: 10/11/2001
• Status: Active Grant

• Current Assignee: Aptiv Technologies AG (Aptiv PLC)
• Original Assignee: PureDepth Limited (Aptiv PLC)
• Inventors: Bell, Gareth Paul, Engel, Gabriel Damon
• Primary Examiner(s): DUONG, THOI V
• Application Number:
  US10/492,624
• Publication Number:
  US 20050062410A1
• Time in Patent Office: 3,462 Days
• Field of Search: 313/506, 313/503, 313/504, 445/24, 445/25, 349/74, 349/65, 349/69, 349/70, 349/96, 349/117, 349/73, 349/15, 349/9, 349/175, 349 61- 63, 349/12, 349/113, 349/114, 362/615
• US Class Current: 349/74
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/13471 in which all the liquid crystal cells or layers remain transparent, e.g. FLC, ECB, DAP, HAN, TN, STN, SBE-LC cells G02F1/13475 takes precedence
• CPC Class Codes: G02F 1/13718 based on a change of the texture state of a cholesteric liquid crystal
• CPC Class Codes: G06F 3/1423 controlling a plurality of local displays, e.g. CRT and flat panel display
• CPC Class Codes: G06T 11/60 Editing figures and text; Combining figures or text
• CPC Class Codes: G06T 15/08 Volume rendering

Abstract

A method of adapting a visual unit having a first screen (10) in a first focal plant by the addition of one or more at least partially transparent display screens (20) at least partially overlapping said first screen (10) and located in focal planes distinct from said first focal plane, characterized in that an at least partially transparent emissive layer (21) is provided between said first screen (10) and at least one said additional display screen (20).

Claims

1. A display device comprising:

a first display screen operable to display a first image;

a second display screen operable to display a second image, wherein said first display screen overlaps said second display screen, and wherein said second image is visible through said first display screen; and

a partially transparent emissive layer disposed between said first and second display screens, wherein said partially transparent emissive layer comprises a first side and a second side, wherein light emitted from said first side is operable to illuminate said first image, and wherein light emitted from said second side is operable to illuminate said second image responsive to a reflection thereof by said second display screen.

2. The display device of claim 1, wherein said partially transparent emissive layer comprises a light guide.

3. The display device of claim 1, wherein said partially transparent emissive layer comprises a transparent organic light emitting diode (TOLED) assembly.

4. The display device of claim 1, wherein said partially transparent emissive layer is a polarized transparent organic light emitting diode (TOLED) emissive layer, and wherein said display device further comprises:

a wire grid polarizer disposed between said partially transparent emissive layer and said first display screen.

5. The display device of claim 4, wherein said wire grid polarizer is operable to reflect polarized light emitted from said partially transparent emissive layer back through said partially transparent emissive layer towards said second display screen.

6. The display device of claim 1 further comprising:

an optical retarder disposed between said partially transparent emissive layer and said second display screen.

7. The display device of claim 6, wherein said optical retarder is a quarter wave retarder.

8. The display device of claim 1, wherein said first and second display screens are liquid crystal displays.

9. The display device of claim 1, wherein said second display screen is selected from a group consisting of a cholesteric liquid crystal display and electronic paper.

10. The display device of claim 1, wherein said second display screen reflects between 10 percent and 100 percent of incident light.

11. A portable electronic device comprising:

a processor;

a memory; and

a display device comprising;

a first display screen operable to display a first image;

a second display screen operable to display a second image, wherein said first display screen overlaps said second display screen, and wherein said second image is visible through said first display screen; and

a partially transparent emissive layer disposed between said first and second display screens, wherein said partially transparent emissive layer comprises a first side and a second side, wherein light emitted from said first side is operable to illuminate said first image, and wherein light emitted from said second side is operable to illuminate said second image responsive to a reflection thereof by said second display screen.

12. The portable electronic device of claim 11, wherein said partially transparent emissive layer comprises a light guide.

13. The portable electronic device of claim 11, wherein said partially transparent emissive layer comprises a transparent organic light emitting diode (TOLED) assembly.

14. The portable electronic device of claim 11, wherein said partially transparent emissive layer is a polarized transparent organic light emitting diode (TOLED) emissive layer, and wherein said display device further comprises:

a wire grid polarizer disposed between said partially transparent emissive layer and said first display screen.

15. The portable electronic device of claim 14, wherein said wire grid polarizer is operable to reflect polarized light emitted from said partially transparent emissive layer back through said partially transparent emissive layer towards said second display screen.

16. The portable electronic device of claim 11, wherein said display device further comprises:

an optical retarder disposed between said partially transparent emissive layer and said second display screen.

17. The portable electronic device of claim 11, wherein said optical retarder is a quarter wave retarder.

18. The portable electronic device of claim 11, wherein said first and second display screens are liquid crystal displays.

19. The portable electronic device of claim 11, wherein said second display screen is selected from a group consisting of a cholesteric liquid crystal display and electronic paper.

20. The portable electronic device of claim 11, wherein said second display screen reflects between 10 percent and 100 percent of incident light.

21. The portable electronic device of claim 11 further comprising:

at least one touch screen.

22. A method of manufacturing a display device, said method comprising:

placing a first display screen and a second display screen in an overlapping arrangement, wherein said first display screen is operable to display a first image, wherein said second display screen is operable to display a second image, wherein said first display screen overlaps said second display screen, and wherein said second image is visible through said first display screen; and

disposing a partially transparent emissive layer between said first and second display screens, wherein said partially transparent emissive layer comprises a first side and a second side, wherein said disposing further comprises disposing said partially transparent emissive layer such that light emitted from said first side is operable to illuminate said first image, and wherein said disposing further comprises disposing said partially transparent emissive layer such that light emitted from said second side is operable to illuminate said second image responsive to a reflection thereof by said second display screen.

23. The method of claim 22, wherein said partially transparent emissive layer comprises a light guide.

24. The method of claim 22, wherein said partially transparent emissive layer comprises a transparent organic light emitting diode (TOLED) assembly.

25. The method of claim 22, wherein said partially transparent emissive layer is a polarized transparent organic light emitting diode (TOLED) emissive layer, and wherein said method further comprises:

disposing a wire grid polarizer between said partially transparent emissive layer and said first display screen.

26. The method of claim 25, wherein said wire grid polarizer is operable to reflect polarized light emitted from said partially transparent emissive layer back through said partially transparent emissive layer towards said second display screen.

27. The method of claim 22, wherein said method further comprises:

disposing an optical retarder between said partially transparent emissive layer and said second display screen.

28. The method of claim 27, wherein said optical retarder is a quarter wave retarder.

29. The method of claim 22, wherein said first and second display screens are liquid crystal displays.

30. The method of claim 22, wherein said second display screen is selected from a group consisting of a cholesteric liquid crystal display and electronic paper.

31. The method of claim 22, wherein said second display screen reflects between 10 percent and 100 percent of incident light.