Display Device

• US 20110051034A1
• Filed: 11/09/2010
• Published: 03/03/2011
• Est. Priority Date: 01/31/2006
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Egi, Yuji, Nishi, Takeshi, Ishitani, Tetsuji
• Granted Patent: US 9,164,313 B2
• Time in Patent Office: Days
• US Class Current: 349/61
• CPC Class Codes: G02F 1/133531 characterised by the arrangement of polariser or analyser axes
• CPC Class Codes: G02F 1/133533 Colour selective polarisers G02F1/1347 takes precedence
• CPC Class Codes: G02F 1/13363 Birefringent elements, e.g. for optical compensation
• CPC Class Codes: G02F 2203/04 wavelength independent
• CPC Class Codes: G02F 2203/64 Normally black display, i.e. the off state being black

Abstract

To provide a display device having a high contrast ratio by a simple and easy method and to manufacture a high-performance display device at low cost, in a display device having a display element between a pair of light-transmitting substrates, layers each including a polarizer having different wavelength distribution of extinction coefficient from each other with respect to the absorption axes are stacked and provided on an outer side of the light-transmitting substrates. Further, a retardation plate may be provided between the stacked polarizers.

Claims

1. A display device comprising:

a first light-transmitting substrate and a second light-transmitting substrate which are disposed to face each other;

a display element sandwiched between the first light-transmitting substrate and the second light-transmitting substrate; and

a layer including stacked polarizers provided between a viewer and the first light-transmitting substrate;

wherein the stacked polarizers are arranged to so that their absorption axes are deviated from a parallel Nicols state.

6. The display device according to claim 1, wherein the layer including the stacked polarizers has a first polarizer and a second polarizer which are sequentially stacked from the first light-transmitting substrate.

11. The display device according to claim 1, wherein the display element is a liquid crystal element.

16. The display device according to claim 1, further comprising:

a light source on an outer side of the second light-transmitting substrate.

21. The display device according to claim 16, wherein the light source is light emitting diode (LED).

26. The display device according to claim 21, wherein the light emitting diode (LED) is configured to be driven by a successive additive color mixture method (a filed sequential method).

31. The display device according to claim 1, wherein the display device is one selected the group consisting of a television device, a digital camera, a digital video camera, a mobile phone, a portable information terminal (PDA), a portable game machine, a monitor for computer, and an image reproducing device.

2. A display device comprising:

a first light-transmitting substrate and a second light-transmitting substrate which are disposed to face each other;

a display element sandwiched between the first light-transmitting substrate and the second light-transmitting substrate;

a first layer including first stacked polarizers provided between a viewer and the first light-transmitting substrate; and

a second layer including second stacked polarizers on an outer side of the second light-transmitting substrate,

wherein the first stacked polarizers are arranged so that their absorption axes are deviated from a parallel Nicols state, and

wherein the second stacked polarizers are arranged so that their absorption axes are in a parallel Nicols state.

7. The display device according to claim 2, wherein the first layer including the first stacked polarizers has a first polarizer and a second polarizer which are sequentially stacked from the first light-transmitting substrate.

12. The display device according to claim 2, wherein the display element is a liquid crystal element.

17. The display device according to claim 2, further comprising:

a light source on an outer side of the second layer.

22. The display device according to claim 17, wherein the light source is light emitting diode (LED).

27. The display device according to claim 22, wherein the light emitting diode (LED) is configured to be driven by a successive additive color mixture method (a filed sequential method).

32. The display device according to claim 2, wherein the display device is one selected the group consisting of a television device, a digital camera, a digital video camera, a mobile phone, a portable information terminal (PDA), a portable game machine, a monitor for computer, and an image reproducing device.

3. A display device comprising:

a first light-transmitting substrate and a second light-transmitting substrate which are disposed to face each other;

a display element sandwiched between the first light-transmitting substrate and the second light-transmitting substrate;

a layer including stacked polarizers between a viewer and the first light-transmitting substrate; and

a retardation plate provided between the first light-transmitting substrate and the layer;

wherein the stacked polarizers are arranged so that their absorption axes are deviated from a parallel Nicols state.

8. The display device according to claim 3, wherein the layer including the stacked polarizers has a first polarizer and a second polarizer which are sequentially stacked from the first light-transmitting substrate.

13. The display device according to claim 3, wherein the display element is a liquid crystal element.

18. The display device according to claim 3, further comprising:

a light source on an outer side of the second light-transmitting substrate.

23. The display device according to claim 18, wherein the light source is light emitting diode (LED).

28. The display device according to claim 23, wherein the light emitting diode (LED) is configured to be driven by a successive additive color mixture method (a filed sequential method).

33. The display device according to claim 3, wherein the display device is one selected the group consisting of a television device, a digital camera, a digital video camera, a mobile phone, a portable information terminal (PDA), a portable game machine, a monitor for computer, and an image reproducing device.

4. A display device comprising:

a first light-transmitting substrate and a second light-transmitting substrate which are disposed to face each other;

a display element sandwiched between the first light-transmitting substrate and the second light-transmitting substrate;

a first layer including first stacked polarizers provided between a viewer and the first light-transmitting substrate;

a retardation plate between the first light-transmitting substrate and the first layer; and

a second layer including second stacked polarizers on an outer side of the second light-transmitting substrate,

wherein the first stacked polarizers are arranged so that their absorption axes are deviated from a parallel Nicols state, and

wherein the second stacked polarizers are arranged so that their absorption axes are in a parallel Nicols state.

9. The display device according to claim 4, wherein the first layer including the first stacked polarizers has a first polarizer and a second polarizer which are sequentially stacked from the first light-transmitting substrate.

14. The display device according to claim 4, wherein the display element is a liquid crystal element.

19. The display device according to claim 4, further comprising:

a light source on an outer side of the second layer.

24. The display device according to claim 19, wherein the light source is light emitting diode (LED).

29. The display device according to claim 24, wherein the light emitting diode (LED) is configured to be driven by a successive additive color mixture method (a filed sequential method).

34. The display device according to claim 4, wherein the display device is one selected the group consisting of a television device, a digital camera, a digital video camera, a mobile phone, a portable information terminal (PDA), a portable game machine, a monitor for computer, and an image reproducing device.

5. A display device comprising:

a first light-transmitting substrate and a second light-transmitting substrate which are disposed to face each other;

a display element sandwiched between the first light-transmitting substrate and the second light-transmitting substrate;

a first layer including first stacked polarizers provide between a viewer and the first light-transmitting substrate;

a first retardation plate between the first light-transmitting substrate and the first layer;

a second layer including second stacked polarizers on an outer side of the second light-transmitting substrate; and

a second retardation plate between the second light-transmitting substrate and the second layer,

wherein the first stacked polarizers are arranged so that their absorption axes are deviated from a parallel Nicols state, and

wherein the second stacked polarizers are arranged to so that their absorption axes are in a parallel Nicols state.

10. The display device according to claim 5, wherein the first layer including the first stacked polarizers has a first polarizer and a second polarizer which are sequentially stacked from the first light-transmitting substrate.

15. The display device according to claim 5, wherein the display element is a liquid crystal element.

20. The display device according to claim 5, further comprising:

a light source on an outer side of the second layer.

25. The display device according to claim 20, wherein the light source is light emitting diode (LED).

30. The display device according to claim 25, wherein the light emitting diode (LED) is configured to be driven by a successive additive color mixture method (a filed sequential method).

35. The display device according to claim 5, wherein the display device is one selected the group consisting of a television device, a digital camera, a digital video camera, a mobile phone, a portable information terminal (PDA), a portable game machine, a monitor for computer, and an image reproducing device.