Liquid crystal display

• US 20040160537A1
• Filed: 02/10/2004
• Published: 08/19/2004
• Est. Priority Date: 12/26/1997
• 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: Okamoto, Masayuki, Mitsui, Seiichi, Hiraki, Hajime
• Granted Patent: US 7,050,132 B2
• Time in Patent Office: Days
• US Class Current: 349/12
• CPC Class Codes: G02F 1/133371 Cells with varying thickness of the liquid crystal layer
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/133638 Waveplates, i.e. plates with a retardation value of lambda/n
• CPC Class Codes: G02F 1/133753 with different alignment orientations or pretilt angles on a same surface, e.g. for grey scale or improved viewing angle
• CPC Class Codes: G02F 2202/04 dye

Abstract

A liquid crystal display is furnished with: a liquid crystal display element having a pair of substrates, to which alignment members are provided to their respective opposing surfaces, and a liquid crystal layer sandwiched by the pair of substrates; an alignment mechanism for providing at least two different director configurations simultaneously on different arbitrary regions used for display in the liquid crystal layer; and a reflection film provided to at least one of the different arbitrary regions showing different director configurations; wherein the different arbitrary regions showing different director configurations are used for a reflection display section for showing reflection display and a transmission display section for showing transmission display, respectively. Examples of the alignment mechanism include an alignment film to which the alignment treatment is applied in different orientations in the reflection display section and transmission display section, respectively, an insulation film having different film thicknesses in the reflection display section and transmission display section, and so forth.

Claims

1. A liquid crystal display comprising:

a liquid crystal display element having a pair of substrates, to which alignment means are provided to their respective opposing surfaces, and a liquid crystal layer sandwiched by said pair of substrates;

an alignment mechanism for providing at least two different director configurations simultaneously on different arbitrary regions used for display in said liquid crystal layer; and

reflecting means provided to at least one of said different arbitrary regions showing different director configurations,

wherein said different arbitrary regions showing different director configurations are used for a reflection display section for showing reflection display and a transmission display section for showing transmission display, respectively.

2. The liquid crystal display of claim 1, wherein said alignment mechanism serves as display content overwriting means for overwriting a display content with an evolution of time.

3. The liquid crystal display of claim 1, wherein said alignment mechanism is said pair of substrates of said liquid crystal display provided with said alignment means;

wherein said alignment means is provided such that, in a region of at least one of said substrates touching a region of said liquid crystal layer used for display, at least two different director directions are imparted to a director configuration of said liquid crystal layer at an interface with said region of said substrate.

4. The liquid crystal display of claim 1, wherein an area of said reflection display section accounts for 30% or above and 90% or less of a total of areas of said reflection display section and said transmission display section.

5. The liquid crystal display of claim 1, wherein, when said transmission display section shows light display, said reflection display section also shows light display, and when said transmission display section shows dark display, said reflection display section also shows dark display.

6. The liquid crystal display of claim 1, wherein said liquid crystal layer is made of liquid crystal composition prepared by blending a dichroic dye with liquid crystal.

7. The liquid crystal display of claim 1, further comprising a polarization plate provided to at least one of said pair of substrates on a surface which does not touch said liquid crystal layer.

8. The liquid crystal display of claim 7, further comprising voltage applying means for applying a voltage to said liquid crystal layer in such a manner that display light on said reflecting means of said reflection display section has a phase difference of approximately 90°

between the light display and the dark display, and display light going out from said liquid crystal layer in said transmission display section has a phase difference of approximately 180°

between the light display and dark display.

9. The liquid crystal display of claim 7, wherein said liquid crystal layer is aligned with a twist between said pair of substrates at a twist angle in a range between 60°

and 100°

inclusive.

10. The liquid crystal display of claim 7, wherein said liquid crystal layer is aligned with a twist between said pair of substrates at a twist angle in a range between 0°

and 40°

inclusive.

11. The liquid crystal display of claim 1, wherein said liquid crystal display element shows the display by changing the director configuration of said liquid crystal layer by rotating liquid crystal molecules in parallel with said pair of substrates in at least one of said reflection display section and said transmission display section.

12. The liquid crystal display of claim 11, wherein said liquid crystal display element includes voltage applying means for generating an electric field in said liquid crystal layer along an in-plane direction of said pair of substrates in one of said reflection display section and said transmission display section.

13. The liquid crystal display of claim 1, wherein at least one of said pair of substrates includes a vertical aligning alignment film on a surface touching said liquid crystal layer at a region corresponding to at least one of said reflection display section and said transmission display section.

14. The liquid crystal display of claim 1, wherein, in at least one of said pair of substrates, a region corresponding to said reflection display section is thicker than a region corresponding to said transmission display section.

15. The liquid crystal display of claim 14, wherein at least one of said pair of substrates includes an insulation film at least on the region corresponding to said reflection display section, said insulation film being thicker in the region corresponding to said reflection display section than in the region corresponding to said transmission display section.

16. The liquid crystal display of claim 1, wherein, on one of said pair of substrates, among regions making up a display region of each pixel, at least a region corresponding to said transmission display section is provided with a color filter having a transmission color.

17. The liquid crystal display of claim 16, wherein, among regions making up said display region, at least part of a region corresponding to said reflection display section is provided with a color filter having brightness equivalent to brightness of said color filter provided to the region of said substrate corresponding to said transmission display section.

18. The liquid crystal display of claim 16, wherein, among regions making up said display region, at least part of a region corresponding to said reflection display section is provided with a color filter having a transmission color brighter than the transmission color of said color filter provided to the region of said substrate corresponding to said transmission display section.

19. The liquid crystal display of claim 16, wherein a part of said reflection display section does not show color display, and an area of said part is set in accordance with luminous transmittance of the transmission color of said color filter.

20. The liquid crystal display of claim 1, wherein, on one of said pair of substrates, among regions making up a display region of each pixel, at least a region corresponding to said reflection display section is provided with a color filter having a transmission color.