Liquid crystal display and television receiver

• US 8,009,248 B2
• Filed: 09/27/2006
• Issued: 08/30/2011
• Est. Priority Date: 09/30/2005
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Hirata, Mitsuaki, Shigeta, Mitsuhiro, Mizushima, Shigeaki, Nakai, Nobuhiko, Takata, Yoshiki, Yamada, Naoshi, Tsubata, Toshihide
• Primary Examiner(s): Ullah; Akm E
• Application Number:
  US11/990,072
• Publication Number:
  US 20090147186A1
• Time in Patent Office: 1,798 Days
• Field of Search: 349/74, 349/89, 349/117, 349/123, 359/494, 359/690
• US Class Current: 349/74
• CPC Class Codes: G02F 1/133504 Diffusing, scattering, diffracting elements associated to illuminating devices G02F1/133606
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/133604 with lamps
• CPC Class Codes: G02F 1/133707 Structures for producing distorted electric fields, e.g. bumps, protrusions, recesses, slits in pixel electrodes
• 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: G09G 2300/023 Display panel composed of stacked panels
• CPC Class Codes: G09G 2300/0439 Pixel structures
• CPC Class Codes: G09G 2310/0275 Details of drivers for data electrodes, other than drivers for liquid crystal, plasma or OLED displays, not related to handling digital grey scale data or to communication of data to the pixels by means of a current
• CPC Class Codes: G09G 2320/02 Improving the quality of display appearance
• CPC Class Codes: G09G 2320/0285 using tables for spatial correction of display data
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/3611 Control of matrices with row and column drivers

Abstract

A liquid crystal display of the present invention contains a first panel and a second panel being stacked. Adjacent pairs of polarizers (A to C) disposed on the panels form crossed Nicols. When the first panel produces a display according to a first display signal, the second panel produces a display according to a second display signal obtained from the first display signal. Each of the two joined panels is provided with a light diffusion layer having a light diffusing property. The provision of the light diffusion layers enables reducing moire pattern occurrences which would otherwise markedly increase when two liquid crystal panels are stacked. As a result, the liquid crystal display has high display quality.

Claims

1. A liquid crystal display, comprising two or more liquid crystal panels being stacked, at least one of the panels including a light diffusion layer having a light diffusing property, and further comprising:

a vertical alignment liquid crystal layer;

a first substrate and a second substrate facing each other across the liquid crystal layer;

a first electrode provided on a side, of the first substrate, which faces the liquid crystal layer and a second electrode provided on a side, of the second substrate, which faces the liquid crystal layer; and

at least one alignment film provided to contact the liquid crystal layer,

wherein;

pixel regions are each divided into a first, a second, a third, and a fourth liquid crystal domain, liquid crystal molecules in the liquid crystal layer near a center with respect to a layer plane and a thickness direction exhibiting a tilt direction parallel to a predetermined, first direction in the first liquid crystal domain, a predetermined, second direction in the second liquid crystal domain, a predetermined, third direction in the third liquid crystal domain, and a predetermined, fourth direction in the fourth liquid crystal domain when a voltage is applied across the first and second electrodes;

a difference between any given pair of the first, second, third, and fourth directions is substantially equal to an integral multiple of 90°

; and

the first, second, third, and fourth liquid crystal domains are adjacent to other liquid crystal domains and are arranged in a 2×

2 matrix.

2. The liquid crystal display of claim 1, wherein there are provided polarized light absorbing layers sandwiching the liquid crystal panels so as to form crossed Nicols.

3. The liquid crystal display of claim 1, wherein the liquid crystal panels each produce a display according to a display signal.

4. The liquid crystal display of claim 1, wherein the light diffusion layer is provided on a display plane side of the stacked liquid crystal panels.

5. The liquid crystal display of claim 4, wherein the light diffusion layer provided on the display plane side has a haze value of 56% or greater.

6. The liquid crystal display of claim 4, wherein the light diffusion layer provided on the display plane side has a haze value of 50% or greater.

7. The liquid crystal display of claim 4, wherein the light diffusion layer provided on the display plane side has a haze value of 56% or greater.

8. The liquid crystal display of claim 4, wherein the light diffusion layer provided on the display plane side has a haze value of 72% or greater.

9. The liquid crystal display of claim 1, wherein the light diffusion layer is provided between the stacked liquid crystal panels.

10. The liquid crystal display of claim 9, wherein the light diffusion layer provided between the stacked liquid crystal panels has a haze value of 42% or greater.

11. The liquid crystal display of claim 9, wherein the light diffusion layer provided between the stacked liquid crystal panels has a haze value of 56% or greater.

12. The liquid crystal display of claim 1, wherein at least two of the panels each include a light diffusion layer having a light diffusing property, one of the light diffusion layers being provided on a display plane side of the stacked liquid crystal panels, and another one of the light diffusion layers being provided between the stacked liquid crystal panels.

13. The liquid crystal display of claim 12, wherein the light diffusion layer provided on the display plane side of the stacked liquid crystal panels and the light diffusion layer provided between the stacked liquid crystal panels each have a haze value of 36% or greater.

14. The liquid crystal display of claim 12, wherein the light diffusion layer provided on the display plane side of the stacked liquid crystal panels and the light diffusion layer provided between the stacked liquid crystal panels each have a haze value of 50% or greater.

15. The liquid crystal display of claim 12, wherein the light diffusion layer provided on the display plane side of the stacked liquid crystal panels and the light diffusion layer provided between the stacked liquid crystal panels each have a haze value of 56% or greater.

16. The liquid crystal display of claim 9, wherein the light diffusion layer provided between the stacked liquid crystal panels has a haze value less than 80%.

17. The liquid crystal display of claim 4, wherein there are provided at least two polarized light absorbing layers between the stacked liquid crystal panels, and there is provided a light diffusion layer between the at least two polarized light absorbing layers.

18. The liquid crystal display of claim 1, wherein the light diffusion layer(s) contain(s) particles being dispersed therein, the particles having a different refractive index from a base material.

19. The liquid crystal display of claim 18, wherein the particles have an average particle diameter of 370 nm or longer.

20. The liquid crystal display of claim 18, wherein the particles have an average particle diameter of 520 nm or longer.

21. The liquid crystal display of claim 18, wherein the particles have an average particle diameter of 3.7 μ

m or longer.

22. The liquid crystal display of claim 1, wherein at least one of substrates constituting the stacked liquid crystal panels, the particular substrate facing an adjacent panel, is thinner than the substrates which do not face the adjacent panel.

23. The liquid crystal display of claim 1, wherein adjacent liquid crystal panels have dots constituted by like elements, the elements in one of the adjacent panels being formed symmetrical to the elements in the other panel.

24. The liquid crystal display of claim 1, wherein only one of the liquid crystal panels includes a color filter.

25. The liquid crystal display of claim 1, further comprising display control means for blurring so that one of the stacked liquid crystal panels displays a blurred image when compared to an image displayed on another liquid crystal panel.

26. The liquid crystal display of claim 1, wherein at least one of the stacked liquid crystal panels has an island-shaped black matrix formed therein.

27. The liquid crystal display of claim 2, wherein the polarized light absorbing layer(s) located internal to an outermost pair of polarized light absorbing layers which forms crossed Nicols has/have a polarizing capability higher than or equal to a predetermined value.

28. The liquid crystal display of claim 27, wherein the polarized light absorbing layer(s) located internal to an outermost pair of polarized light absorbing layers which forms crossed Nicols has/have a higher polarizing capability than the outermost polarized light absorbing layer.

29. The liquid crystal display of claim 28, wherein the polarized light absorbing layer(s) located internal to an outermost pair of polarized light absorbing layers is thicker than the outermost polarized light absorbing layer.

30. The liquid crystal display of claim 28, wherein the polarized light absorbing layer(s) located internal to an outermost pair of polarized light absorbing layers contains a plurality of polarized light absorbing plates being stacked, each plate having the same polarizing capability as the outermost polarized light absorbing layer.

31. The liquid crystal display of claim 1, wherein the liquid crystal panels each have a vertical alignment liquid crystal layer.

32. The liquid crystal display of claim 1, wherein the liquid crystal panels each have alignment controlling projections and/or electrode openings to regulate alignment direction of liquid crystal.