Liquid crystal display panel

• US 6,690,438 B2
• Filed: 04/06/2001
• Issued: 02/10/2004
• Est. Priority Date: 04/06/2001
• Status: Expired due to Fees

• Current Assignee: Citizen Holdings Co., Ltd.
• Original Assignee: Citizen Watch Co Limited (Citizen Electronics Company Limited)
• Inventors: Sekiguchi, Kanetaka
• Primary Examiner(s): Parker, Kenneth
• Application Number:
  US09/827,293
• Publication Number:
  US 20020145688A1
• Time in Patent Office: 1,040 Days
• Field of Search: 349/114, 349/43, 349/106
• US Class Current: 349/114
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133555 Transflectors

Abstract

A liquid crystal layer (15) is sandwiched between a first substrate (1) provided on a visible side and a second substrate (5) opposed to the first substrate; a first color filter (9) is provided on the first substrate (1) or on the second substrate (5); a transflective reflector (24) is provided on the opposite side to the visible side of the first color filter (9), which transmits a part of light and reflecting almost all the remaining light; and a second color filter (28) is provided on the opposite side to the first color filter (9) with respect to the transflective reflector (24), thereby forming a liquid crystal display panel.

Claims

1. A liquid crystal display panel, comprising:

a first substrate provided on a visible side;

a second substrate opposed to said first substrate;

a liquid crystal layer sandwiched between said first substrate and said second substrate;

a first color filter provided in-between said first substrate and said second substrate;

a transflective reflector, provided on an opposite side to said visible side of said liquid crystal layer and said first color filter, for transmitting a part of light and substantially reflecting all the remaining light; and

a second color filter provided on an opposite side to said first color filter with respect to said transflective reflector;

wherein said transflective reflector is provided on an opposite side to said visible side of said second substrate, and said second color filter is provided on an opposite side to said second substrate with respect to said transflective reflector.

2. A liquid crystal display panel according to claim 1, further comprising:

signal electrodes provided on said first substrate;

opposed electrodes provided on said second substrate to form pixel portions where said signal electrodes and said opposed electrodes coincide as viewed in a plan view; and

a transflective reflector removed portion without providing said transflective reflector provided around a display region constituted of a plurality of said pixel portions.

3. A liquid crystal display panel according to claim 2,

wherein said first color filter and said second color filter are constituted of filters of a plurality of colors respectively, and

wherein said filters of different colors are arranged in said first color filter and said second color filter within a region of said transflective reflector removed portion.

4. A liquid crystal display panel according to claim 3,

wherein said second color filter is constituted of filters of a plurality of colors, and

wherein said second color filter is formed by laminating said filters of different colors within a region of said transflective reflector removed portion.

5. A liquid crystal display panel according to claim 2, further comprising:

a light shielding member having a reflectance lower than that of said transflective reflector and a light shielding property provided on said first substrate or on said second substrate within a region of said transflective reflector removed portion.

6. A liquid crystal display panel according to claim 1,

wherein said transflective reflector has irregularities on a front face thereof and a light diffusing property.

7. A liquid crystal display panel according to claim 1, wherein said second color filter is provided contacting a surface on an opposite side to said visible side of said transflective reflector.

8. A liquid crystal display panel according to claim 1, wherein said first color filter and said second color filter have substantially same pixel pitch.

9. A liquid crystal display panel according to claim 8,

wherein said first color filter and said second color filter are constituted of filters of a plurality of colors respectively, so that said filters of same color are arranged to coincide as viewed in a plan view in each pixel.

10. A liquid crystal display panel according to claim 1, further comprising:

signal electrodes provided on said first substrate; and

opposed electrodes provided on said second substrate to form pixel portions where said signal electrodes and said opposed electrodes coincide as viewed in a plane view,

wherein said transflective reflector is disposed on an opposite side to said visible side of said second substrate,

said first color filter and said second color filter are provided at positions corresponding to said pixel portions respectively,

said first color filter is constituted of filters of a plurality of colors which are different in color at portions corresponding to adjacent pixel portions, and

said second color filter is provided with a light shielding layer at positions corresponding to gaps between adjacent pixel portions.

11. A liquid crystal display panel according to claim 1,

wherein said first color filter and said second color filter have aligning marks respectively.

12. A liquid crystal display panel according to claim 1, further comprising:

signal electrodes provided on said first substrate;

opposed electrodes provided on said second substrate to form pixel portions where said signal electrodes and said opposed electrodes coincide as viewed in a plan view;

a first polarizer provided on said visible side of said first substrate;

a second polarizer provided on an opposite side to said visible side of said second substrate; and

a white diffuser provided between said first substrate and said first polarizer,

wherein said first color filter is constituted of filters of a plurality of colors corresponding to said pixel portions, and

said transflective reflector is disposed on an opposite side to said visible side of said second substrate.

13. A liquid crystal display panel according to claim 1,

wherein said liquid crystal layer is constituted of a scattering liquid crystal.

14. A liquid crystal display panel according to claim 13,

further comprising an ultraviolet filtering film on said visible side of said first substrate, for absorbing or reflecting ultraviolet light.

15. A liquid crystal display panel according to claim 13,

wherein said second substrate is a transparent plastic substrate or plastic film substrate.

16. A liquid crystal display panel according to claim 1, wherein said transflective reflector has a transmitting hole portion with a high transmittance and a reflecting portion with a high reflectance.

17. A liquid crystal display panel according to claim 16, further comprising:

signal electrodes provided on said first substrate; and

opposed electrodes provided on said second substrate to form pixel portions where said signal electrodes and said opposed electrodes coincide as viewed in a plan view,

wherein said transmitting hole portion of said transflective reflector is provided inside said pixel portion.

18. A liquid crystal display panel according to claim 17,

wherein said second color filter is constituted of filters of a plurality of colors and overlapping portions where adjacent filters constituting said second filter overlap one upon another are provided between said pixel portions.

19. A liquid crystal display panel according to claim 18,

wherein said first color filter is also constituted of filters of a plurality of colors and overlapping portions where adjacent filters constituting said first color filter overlap one upon another are provided between said pixel portions.

20. A liquid crystal display panel, comprising:

a first substrate provided on a visible side;

a second substrate opposed to said first substrate;

a liquid crystal layer sandwiched between said first substrate and said second substrate;

a first color filter provided inbetween said first substrate and said second substrate;

a transflective reflector, provided on an opposite side to said visible side of said liquid crystal layer and said first color filter, for transmitting a part of light and substantially reflecting all the remaining light; and

a second color filter provided on the opposite side to said first color filter with respect to said transflective reflector;

wherein said first color filter, said transflective reflector and said second color filter are provided on a surface on said visible side of said second substrate in an order of said second color filter, said transflective reflector and said first color filter from said second substrate side.

21. A liquid crystal display panel according to claim 20, wherein said transflective reflector has a transmitting hole portion with a high transmittance and a reflecting portion with a high reflectance.

22. A liquid crystal display panel according to claim 21, further comprising:

signal electrodes provided on said first substrate and;

opposed electrodes provided on said second substrate to form pixel portions where said signal electrodes and said opposed electrodes coincide as viewed in a plan view,

wherein said transmitting hole portion of said transflective reflector is provided inside said pixel portion.

23. A liquid crystal display panel according to claim 22,

wherein said second color filter is constituted of filters of a plurality of colors and overlapping portions where adjacent filters constituting said second color filter overlap one upon another are provided between said pixel portions.

24. A liquid crystal display panel according to claim 23,

wherein said first color filter is also constituted of filters of a plurality of colors and overlapping portions where adjacent filters constituting said first color filter overlap one upon another are provided between said pixel portions.

25. A liquid crystal display panel according to claim 20, further comprising:

signal electrodes provided on said first substrate;

opposed electrodes provided on said second substrate to form pixel portions where said signal electrodes and said opposed electrodes coincide as viewed in a plan view; and

a transflective reflector removed portion without providing said transflective reflector provided around a display region constituted of a plurality of said pixel portions.

26. A liquid crystal display panel according to claim 25,

wherein said first color filter and said second color filter are constituted of filters of a plurality of colors respectively, and

wherein said filters of different colors are arranged in said first color filter and said second color filter within a region of said transflective reflector removed portion.

27. A liquid crystal display panel according to claim 25,

wherein said second color filter is constituted of filters of a plurality of colors, and wherein said second color filter is formed by laminating said filters of different colors within a region of said transflective reflector removed portion.

28. A liquid crystal display panel according to claim 25, further comprising:

a light shielding member having a reflectance lower than that of said transflective reflector and a light shielding property provided on said first substrate or on said second substrate within a region of said transflective reflector removed portion.

29. A liquid crystal display panel according to claim 20,

wherein said transflective reflector has irregularities on a front face thereof and a light diffusing property.

30. A liquid crystal display panel according to claim 20,

wherein said first color filter and said second color filter have substantially the same pixel pitch.

31. A liquid crystal display panel according to claim 30,

wherein said first color filter and said second color filter are constituted of filters of a plurality of colors respectively, so that said filters of same color are arranged to coincide as viewed in a plan view in each pixel.

32. A liquid crystal display panel according to claim 20, further comprising:

signal electrodes provided on said first substrate; and

opposed electrodes provided on said second substrate to form pixel portions where said signal electrodes and said opposed electrodes coincide as viewed in a plane view,

wherein said transflective reflector is disposed on an opposite side to said visible side of a said second substrate,

said first color filter and said second color filter are provided at positions corresponding to said pixel portions respectively,

said first color filter is constituted of filters of a plurality of colors which are different in color at portions corresponding to adjacent pixel portions, and

said second color filter is provided with a light shielding layer at positions corresponding to gaps between adjacent pixel portions.

33. A liquid crystal display panel according to claim 20,

wherein said transflective reflector has an optical polarizing characteristic.

34. A liquid crystal display panel according to claim 20,

wherein said first color filter and said second color filter have aligning marks respectively.

35. A liquid crystal display panel according to claim 20, further comprising:

signal electrodes provided on said first substrate;

opposed electrodes provided on said second substrate to form pixel portions where said signal electrodes and said opposed electrodes coincide as viewed in a plan view;

a first polarizer provided on said visible side of said first substrate;

a second polarizer provided on the opposite side to said visible side of said second substrate; and

a white diffuser provided between said first substrate and said first polarizer,

wherein said first color filter is constituted of filters of a plurality of colors corresponding to said pixel portions, and

said transflective reflector is disposed on an opposite side to said visible side of said seconds substrate.

36. A liquid crystal display panel according to claim 20,

wherein said liquid crystal layer is constituted of a scattering liquid crystal.

37. A liquid crystal display panel according to claim 36,

further comprising an ultraviolet filtering film on said visible side of said first substrate, for absorbing or reflecting ultraviolet light.

38. A liquid crystal display panel according to claim 30,

wherein said second substrate is a transparent plastic substrate or plastic film substrate.

39. A liquid crystal display panel, comprising:

a first substrate provided on a visible side;

a second substrate opposed to said first substrate;

a liquid crystal layer sandwiched between said first substrate and said second substrate;

a first color filter provided inbetween said first substrate and said second substrate;

a transflective reflector, provided on an opposite side to said visible side of said first color filter, for transmitting a part of light and substantially reflecting all the remaining light; and

a second color filter provided on the opposite side to said first color filter with respect to said transflective reflector;

wherein said transflective reflector has a transmitting hole portion with a high transmittance and a reflecting portion with a high reflectance,

said transflective reflector is provided on the opposite side to said visible side of said second substrate, and said second color filter is provided on an opposite side to said second substrate with respect to said transflective reflector, and

said second color filter is provided contacting a surface on an opposite side to said visible side of said transflective reflector.

40. A liquid crystal display panel comprising:

a first substrate provided on a visible side;

a second substrate opposed to said first substrate;

a liquid crystal layer sandwiched between said first substrate and said second substrate;

a first color filter provided on said first substrate or on said second substrate;

a transflective reflector, provided on an opposite side to said visible side of said first color filter, for transmitting a part of light and reflecting almost all remaining light; and

a second color filter provided on an opposite side to said first color filter with respect to said transflective reflector;

wherein said transflective reflector has a transmitting hole portion with a high transmittance and a reflecting portion with a high reflectance;

wherein said transflective reflector is provided on an opposite side to said visible side of said second substrate, and said second color filter is provided on an opposite side to said second substrate with respect to said transflective reflector;

wherein said second color filter is provided contacting a surface on an opposite side to said visible side of said transflective reflector.