Display device and electronic device

• US 8,482,484 B2
• Filed: 01/05/2007
• Issued: 07/09/2013
• Est. Priority Date: 06/27/2003
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei, Watanabe, Yasuko
• Primary Examiner(s): Bolotin, Dmitriy
• Application Number:
  US11/620,439
• Publication Number:
  US 20070108454A1
• Time in Patent Office: 2,377 Days
• Field of Search: 345 30-107, 345/1.1, 345/4, 345/5, 345/173, 345/175, 257/88
• US Class Current: 345/4
• CPC Class Codes: G09G 2340/0492 Change of orientation of the displayed image, e.g. upside-down, mirrored
• CPC Class Codes: G09G 3/30 using electroluminescent panels
• CPC Class Codes: H01L 27/14678 Contact-type imagers
• CPC Class Codes: H10K 2102/3031 Two-side emission, e.g. transparent OLEDs [TOLED]
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]
• CPC Class Codes: H10K 59/65 OLEDs integrated with inorganic image sensors

Abstract

A display device and an electronic device in which more sophistication and a high added value are realized by obtaining a read function by incorporating an imaging device, and by using a panel with small volume can be provided. A display device and an electronic device according to the invention has a first display surface and a plurality of pixels arranged in matrix over one surface of a light transmitting substrate and a second display surface over the other surface of the substrate. The plurality of pixels are each provided with a transistor, an imaging device, and a light-emitting element which emits light to the first display surface and the second display surface. The light-emitting element has two functions of serving as a light source when information of a subject is read and displaying an image. Thus, a display device according to the invention has two functions of an image sensor function to read information of a subject by using an imaging device and a display function to display an image by using the imaging device and the light-emitting element.

Claims

1. A display device comprising:

a substrate which transmits light;

a first display surface above a top surface of the substrate;

a second display surface below a bottom surface of the substrate;

a counter substrate opposite to the substrate;

two polarizers of different polarizations sandwiching the substrate and the counter substrate and between the first display surface and the second display surface; and

a transistor and a light-emitting element between the top surface of the substrate and the first display surface, the transistor being electrically connected to the light-emitting element,

wherein the light-emitting element emits light to the first display surface and to the second display surface,

wherein light emitted by the light-emitting element reaches the first display surface and the second display surface by passing through one polarizer only,

wherein light obtained from the light-emitting element is white, and

wherein each of the first display surface and the second display surface performs monochrome display.

2. A display device according to claim 1, further comprising an imaging device configured to generate signal charge in response to incident light over the top surface of the substrate.

3. A display device according to claim 2, wherein the imaging device includes an amorphous semiconductor.

4. A display device according to claim 2, the light-emitting element comprising an electrode, the electrode comprising an opening overlapping with the imaging device.

5. A display device according to claim 2, wherein an opening overlapping with the imaging device is provided in one or more of the two polarizers.

6. An electronic device selected from the group consisting of a portable cellular phone, a tablet PC, a wristwatch portable terminal, a digital video camera, and a digital camera comprising the display device according to claim 1.

7. A display device according to claim 1, wherein the display device has a switching circuit which controls a display of the first display surface or the second display surface.

8. A display device according to claim 7, wherein the display is selected from a group consisting of a normal display, a horizontally reversed display, a 180°

rotated display and a vertically reversed display.

9. A display device comprising:

a substrate which transmits light;

a first display surface above a top surface of the substrate;

a second display surface below a bottom surface of the substrate;

a counter substrate opposite to the substrate;

two polarizers of different polarizations sandwiching the substrate and the counter substrate and between the first display surface and the second display surface;

a transistor and a light-emitting element between the top surface of the substrate and the first display surface, the transistor being electrically connected to the light-emitting element; and

a color filter below the bottom surface of the substrate,

wherein the light-emitting element emits light to the first display surface and to the second display surface,

wherein light emitted by the light-emitting element reaches the first display surface and the second display surface by passing through one polarizer only,

wherein light obtained from the light-emitting element is white, and

wherein the first display surface performs monochrome display and the second display surface performs color display.

10. A display device according to claim 9, further comprising an imaging device configured to generate signal charge in response to incident light over the top surface of the substrate.

11. A display device according to claim 10, wherein the imaging device includes an amorphous semiconductor.

12. A display device according to claim 10, the light-emitting element comprising an electrode, the electrode comprising an opening overlapping with the imaging device.

13. A display device according to claim 10, wherein an opening overlapping with the imaging device is provided in one or more of the two polarizers.

14. An electronic device selected from the group consisting of a portable cellular phone, a tablet PC, a wristwatch portable terminal, a digital video camera, and a digital camera comprising the display device according to claim 9.

15. A display device according to claim 9, wherein the display device has a switching circuit which controls a display of the first display surface or the second display surface.

16. A display device according to claim 15, wherein the display is selected from a group consisting of a normal display, a horizontally reversed display, a 180°

rotated display and a vertically reversed display.

17. A display device comprising:

a substrate which transmits light;

a first display surface above a top surface of the substrate;

a second display surface below a bottom surface of the substrate;

a counter substrate opposite to the substrate;

two polarizers of different polarizations sandwiching the substrate and the counter substrate and between the first display surface and the second display surface;

a transistor and a light-emitting element between the top surface of the substrate and the first display surface, the transistor being electrically connected to the light-emitting element; and

a color filter above the top surface of the substrate and the light-emitting element,

wherein the light-emitting element emits light to the first display surface and to the second display surface,

wherein light emitted by the light-emitting element reaches the first display surface and the second display surface by passing through one polarizer only,

wherein light obtained from the light-emitting element is white, and

wherein the first display surface performs color display and the second display surface performs monochrome display.

18. A display device according to claim 17, further comprising an imaging device configured to generate signal charge in response to incident light over the top surface of the substrate.

19. A display device according to claim 18, wherein the imaging device includes an amorphous semiconductor.

20. A display device according to claim 18, the light-emitting element comprising an electrode, the electrode comprising an opening overlapping with the imaging device.

21. A display device according to claim 18, wherein an opening overlapping with the imaging device is provided in one or more of the two polarizers.

22. An electronic device selected from the group consisting of a portable cellular phone, a tablet PC, a wristwatch portable terminal, a digital video camera, and a digital camera comprising the display device according to claim 17.

23. A display device according to claim 17, wherein the display device has a switching circuit which controls a display of the first display surface or the second display surface.

24. A display device according to claim 23, wherein the display is selected from a group consisting of a normal display, a horizontally reversed display, a 180°

rotated display and a vertically reversed display.

25. A display device comprising:

a substrate which transmits light;

a first display surface above a top surface of the substrate;

a second display surface below a bottom surface of the substrate;

a counter substrate opposite to the substrate;

two polarizers of different polarizations sandwiching the substrate and the counter substrate and between the first display surface and the second display surface;

a transistor and a light-emitting element between the top surface of the substrate and the first display surface, the transistor being electrically connected to the light-emitting element;

a first color filter above the top surface of the substrate and the light-emitting element; and

a second color filter below the bottom surface of the substrate,

wherein the light-emitting element emits light to the first display surface and to the second display surface,

wherein light emitted by the light-emitting element reaches the first display surface and the second display surface by passing through one polarizer only,

wherein light obtained from the light-emitting element is white, and

wherein the first display surface performs color display and the second display surface performs color display.

26. A display device according to claim 25, further comprising an imaging device configured to generate signal charge in response to incident light over the top surface of the substrate.

27. A display device according to claim 26, wherein the imaging device includes an amorphous semiconductor.

28. A display device according to claim 26, the light-emitting element comprising an electrode, the electrode comprising an opening overlapping with the imaging device.

29. A display device according to claim 26, wherein an opening overlapping with the imaging device is provided in one or more of the two polarizers.

30. An electronic device selected from the group consisting of a portable cellular phone, a tablet PC, a wristwatch portable terminal, a digital video camera, and a digital camera comprising the display device according to claim 25.

31. A display device according to claim 25, wherein the display device has a switching circuit which controls a display of the first display surface or the second display surface.

32. A display device according to claim 31, wherein the display is selected from a group consisting of a normal display, a horizontally reversed display, a 180°

rotated display and a vertically reversed display.

33. A display device comprising:

a substrate which transmits light;

a first display surface above a top surface of the substrate;

a second display surface below a bottom surface of the substrate;

a counter substrate opposite to the substrate;

two polarizers of different polarizations sandwiching the substrate and the counter substrate and between the first display surface and the second display surface; and

a transistor and a light-emitting element between the top surface of the substrate and the first display surface, the transistor being electrically connected to the light-emitting element,

wherein the light-emitting element emits light to the first display surface and to the second display surface,

wherein light emitted by the light-emitting element reaches the first display surface and the second display surface by passing through one polarizer only,

wherein light obtained from the light-emitting element is red, blue, or green, and

wherein the first display surface performs color display and the second display surface performs color display.

34. A display device according to claim 33, further comprising an imaging device configured to generate signal charge in response to incident light over the top surface of the substrate.

35. A display device according to claim 34, wherein the imaging device includes an amorphous semiconductor.

36. A display device according to claim 34, the light-emitting element comprising an electrode, the electrode comprising an opening overlapping with the imaging device.

37. A display device according to claim 34, wherein an opening overlapping with the imaging device is provided in one or more of the two polarizers.

38. An electronic device selected from the group consisting of a portable cellular phone, a tablet PC, a wristwatch portable terminal, a digital video camera, and a digital camera comprising the display device according to claim 33.

39. A display device according to claim 33, wherein the display device has a switching circuit which controls a display of the first display surface or the second display surface.

40. A display device according to claim 39, wherein the display is selected from a group consisting of a normal display, a horizontally reversed display, a 180°

rotated display and a vertically reversed display.

41. A display device comprising:

a substrate which transmits light;

a first display surface above a top surface of the substrate;

a second display surface below a bottom surface of the substrate;

a counter substrate opposite to the substrate;

two polarizers of different polarizations sandwiching the substrate and the counter substrate and between the first display surface and the second display surface; and

a transistor and a light-emitting element between the top surface of the substrate and the first display surface, the transistor being electrically connected to the light-emitting element,

wherein the light-emitting element emits light to the first display surface and to the second display surface, and

wherein light emitted by the light-emitting element reaches the first display surface and the second display surface by passing through one polarizer only.