Liquid crystal display

• US 20050140855A1
• Filed: 12/23/2004
• Published: 06/30/2005
• Est. Priority Date: 12/26/2003
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Hitachi Displays Limited (Japan Display Incorporated)
• Inventors: Maehara, Mutsumi, Kondo, Katsumi, Utsumi, Yuka, Sugibayashi, Makiko, Hiyama, Ikuo
• Granted Patent: US 7,489,374 B2
• Time in Patent Office: Days
• US Class Current: 349/106
• CPC Class Codes: G02F 1/133514 Colour filters
• 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 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 1/1393 the birefringence of the liquid crystal being electrically controlled, e.g. ECB-, DAP-, HAN-, PI-LC cells G02F1/1396, G02F1/141 take precedence
• CPC Class Codes: G02F 2203/04 wavelength independent

Abstract

A normally-closed liquid crystal display includes a component to selectively absorb characteristic leakage light occurring at black representation. Therefore, when black is displayed, occurrence of unnecessary leakage light due to partial depolarization of polarized light caused by a component of an LCD panel can be suppressed. It is therefore possible to provide a liquid crystal display in which display performance of black is improved to clearly display black.

Claims

1. A liquid crystal display, comprising:

a pair of substrates including a polarizer;

a liquid crystal layer sandwiched between-the pair of substrates;

an absorbing component including a pigment having dichroism in a wavelength range from 400 nm to 500 nm; and

means for supplying light to the liquid crystal layer.

25. A liquid crystal display according to claim 1, wherein the absorbing component includes a polyvinyl alcohol macromolecular layer including a pigment having an absorption peak at a wavelength of 490 nm.

29. A liquid crystal display according to claim 1, wherein absorption and transmission of the absorbing component vary on a plane of polarization.

31. A liquid crystal display according to claim 1, wherein the absorbing component comprises a glass plate on which a polymer layer is formed.

2. A liquid crystal display, comprising:

a pair of substrates including a polarizer and a color filter layer;

a liquid crystal layer sandwiched between the pair of substrates; and

means for supplying light to the liquid crystal layer, wherein;

the color filter layer includes three filters for displaying blue, green, and red; and

the green filter of the three filters selectively includes an absorbing component.

26. A liquid crystal display according to claim 2, wherein the absorbing component includes a polyvinyl alcohol macromolecular layer including a pigment having an absorption peak at a wavelength of 490 nm.

3. A liquid crystal display, comprising:

a pair of substrates including a polarizer and a color filter layer;

a liquid crystal layer sandwiched between the pair of substrates; and

means for supplying light to the liquid crystal layer, wherein;

the color filter layer includes three filters for displaying blue, green, and red; and

a spectrum absorbing layer is selectively arranged in an upper section or a lower section of the green filter of the three filters.

27. A liquid crystal display according to claim 3, wherein the absorbing component includes a polyvinyl alcohol macromolecular layer including a pigment having an absorption peak at a wavelength of 490 nm.

4. A liquid crystal display of in-plane-switching type, comprising:

a liquid crystal display panel of normally-closed type including a pair of substrates including a polarizer and a liquid crystal layer sandwiched between the pair of substrates; and

a light source arranged on a rear surface of the liquid crystal display panel, wherein;

a component for selectively absorbing light emitted, when incident light incident from the light source to the liquid crystal display panel passes through the display panel, by partial depolarization of polarizations of the light by a constituent component of the display panel is arranged in a light path from the light source to an upper-most surface nearest to an observer of the liquid crystal display panel.

8. A liquid crystal display according to claim 4, wherein the component for selectively absorbing the light is a component for selectively absorbing light emitted, when incident light incident from the light source to the liquid crystal display panel passes through the display panel, through scattering of the light by particles including in a constituent component of the display panel, the particles each having a diameter less than length of visible light.

12. A liquid crystal display according to claim 8, wherein the component for selectively absorbing the light includes a pigment having an absorption characteristic centered on a wavelength range from 480 nm to 500 nm.

15. A liquid crystal display according to claim 8, wherein the liquid crystal panel is a normally-closed liquid crystal panel of in-plane-switching type comprising:

a pair of substrates;

a plurality of data lines arranged on at least one of the pair of substrates;

a plurality of scan lines formed to intersect the data lines;

thin film transistor elements, pixel electrodes, and common electrodes formed in association with intersections between the data lines and the scan lines;

a liquid crystal layer and a pair of polarizers sandwiched between the pair of substrates; and

a color filter layer arranged on at least one of the pair of substrates.

16. A liquid crystal display according to claim 8, wherein the liquid crystal panel is a normally-closed liquid crystal panel of in-plane-switching type comprising:

a pair of substrates including electrodes;

a liquid crystal layer and a pair of polarizers sandwiched between the pair of substrates; and

a color filter layer arranged on at least one of the pair of substrates.

17. A liquid crystal display according to claim 12, wherein the liquid crystal panel is a normally-closed liquid crystal panel of in-plane-switching type comprising:

a pair of substrates;

a plurality of data lines arranged on at least one of the pair of substrates;

a plurality of scan lines formed to intersect the data lines;

thin film transistor elements, pixel electrodes, and common electrodes formed in association with intersections between the data lines and the scan lines;

a liquid crystal layer and a pair of polarizers sandwiched between the pair of substrates; and

a color filter layer arranged on at least one of the pair of substrates.

19. A liquid crystal display according to claim 12, wherein the liquid crystal panel is a normally-closed liquid crystal panel of in-plane-switching type comprising:

a pair of substrates;

a plurality of data lines arranged on at least one of the pair of substrates;

a plurality of scan lines formed to intersect the data lines;

thin film transistor elements, pixel electrodes, and common electrodes formed in association with intersections between the data lines and the scan lines;

a liquid crystal layer and a pair of polarizers sandwiched between the pair of substrates; and

a color filter layer arranged on at least one of the pair of substrates.

5. A liquid crystal display of in-plane-switching type, comprising:

a normally-closed liquid crystal display panel including a pair of substrates including a polarizer and a liquid crystal layer sandwiched between the pair of substrates; and

a light source arranged on a rear surface of the liquid crystal display panel, wherein;

a component for selectively absorbing light emitted, when incident light incident from the light source to the liquid crystal display panel passes through the display panel, by partial depolarization of polarization of the light by a constituent component of the display panel is arranged on an outside of a polarizer arranged on a side of an observer of the liquid crystal display panel.

9. A liquid crystal display according to claim 5, wherein the component for selectively absorbing the light is a component for selectively absorbing light emitted, when incident light incident from the light source to the liquid crystal display panel passes through the display panel, through scattering of the light by particles including in a constituent component of the display panel, the particles each having a diameter less than length of visible light.

13. A liquid crystal display according to claim 5, wherein the component for selectively absorbing the light includes a pigment having dichroism in which absorption and transmission vary on a plane of polarization.

14. A liquid crystal display according to claim 13, wherein the component for selectively absorbing the light includes a pigment having dichroism in which absorption and transmission vary on a plane of polarization in a wavelength range from 400 nm to 500 nm.

18. A liquid crystal display according to claim 13, wherein the liquid crystal panel is a normally-closed liquid crystal panel of in-plane-switching type comprising:

a pair of substrates including electrodes;

a liquid crystal layer and a pair of polarizers sandwiched between the pair of substrates; and

a color filter layer arranged on at least one of the pair of substrates.

20. A liquid crystal display according to claim 13, wherein the liquid crystal panel is a normally-closed liquid crystal panel of in-plane-switching type comprising:

a pair of substrates including electrodes;

a liquid crystal layer and a pair of polarizers sandwiched between the pair of substrates; and

a color filter layer arranged on at least one of the pair of substrates.

6. A liquid crystal display of in-plane-switching type, comprising:

a normally-closed liquid crystal display panel including a pair of substrates including a polarizer and a liquid crystal layer sandwiched between the pair of substrates; and

a light source unit arranged on a rear surface of the liquid crystal display panel, wherein;

a component for selectively absorbing light emitted, when incident light incident from the light source unit to the liquid crystal display panel passes through the display panel, by partial depolarization of polarization of the light by a constituent component of the display panel is arranged in the light source unit.

10. A liquid crystal display according to claim 6, wherein the component for selectively absorbing the light is a component for selectively absorbing light emitted, when incident light incident from the light source to the liquid crystal display panel passes through the display panel, through scattering of the light by particles including in a constituent component of the display panel, the particles each having a diameter less than length of visible light.

7. A liquid crystal display of in-plane-switching type, comprising:

a normally-closed liquid crystal display panel including a pair of substrates including a polarizer and a liquid crystal layer sandwiched between the pair of substrates; and

a light source unit arranged on a rear surface of the liquid crystal display panel, wherein;

a component for selectively absorbing light emitted, when incident light incident from the light source to the liquid crystal display panel passes through the display panel, by partial depolarization of polarization of the light by a constituent component of the display panel is formed in predetermined pixels of a color filter layer included in the liquid crystal display panel.

11. A liquid crystal display according to claim 7, wherein the component for selectively absorbing the light is a component for selectively absorbing light emitted, when incident light incident from the light source to the liquid crystal display panel passes through the display panel, through scattering of the light by particles including in a constituent component of the display panel, the particles each having a diameter less than length of visible light.

21. A liquid crystal display panel, comprising:

a pair of substrates including a polarizer and red, blue, and green color filter layers; and

a liquid crystal layer sandwiched between the pair of substrates, wherein

of incident light to the display panel, light having passed through the green color filter layer has a waveform including two or more peaks.

22. A liquid crystal display panel, comprising:

a pair of substrates including a polarizer and red, blue, and green color filter layers; and

a liquid crystal layer sandwiched between the pair of substrates, wherein

of incident light to the display panel, light having passed through the green color filter layer has a waveform including a concavity.

23. A liquid crystal display, comprising:

a liquid crystal display panel comprising a pair of substrates including a polarizer and red, blue, and green color filter layers and a liquid crystal layer sandwiched between the pair of substrates; and

means for supplying light to the liquid crystal display panel, wherein

of light which is emitted from the-means for supplying light to the liquid crystal display panel and which has passed through the display panel, light having passed through the green color filter layer has a waveform including two or more peaks.

24. A liquid crystal display, comprising:

a liquid crystal display panel comprising a pair of substrates including a polarizer and red, blue, and green color filter layers and a liquid crystal layer sandwiched between the pair of substrates; and

means for supplying light to the liquid crystal display panel, wherein

of light which is emitted from the means for supplying light to the liquid crystal display panel and which has passed through the display panel, light having passed through the green color filter layer has a waveform including a concavity.

28. A liquid crystal display, comprising:

a pair of polarizers arranged opposing to each other;

a pair of substrates arranged opposing to each other, the substrates being in contact with inner sides of the respective polarizers;

a color filter arranged to be in contact with an inner side of one of the pair of substrates;

liquid crystal sandwiched between an inner side of the other one of the pair of substrates and the color filter;

a light emitting component arranged on an outer side of the other one of the pair of substrates for supplying light to the liquid crystal; and

an absorbing component disposed between the other one of the pair of substrates and the light emitting component, the absorbing component including a pigment having dichroism in a wavelength range from 400 nm to 500 nm of light from the light emitting component.

30. A liquid crystal display according to claim 28, wherein absorption and transmission of the absorbing component vary on a plane of polarization.

32. A liquid crystal display according to claim 28, wherein absorbing component comprises a glass plate on which a polymer layer is formed.