Liquid crystal display

• US 6,563,554 B2
• Filed: 06/25/2001
• Issued: 05/13/2003
• Est. Priority Date: 12/26/1997
• Status: Expired due to Term

• 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
• Primary Examiner(s): Ton, Toan
• Assistant Examiner(s): Duong, Tai V.
• Application Number:
  US09/887,442
• Publication Number:
  US 20010052948A1
• Time in Patent Office: 687 Days
• Field of Search: 349/12, 349/61, 349/106, 349/117, 349/119, 349/128, 349/129, 349/130, 349/141, 349/165, 349/180, 349/191
• 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 opposing each other, at least one polarization plate, and a liquid crystal layer sandwiched by said pair of substrates, wherein:

a display region of said liquid crystal layer includes regions of at least two different thicknesses of said liquid crystal layer;

said regions of at least two different thicknesses are used for a reflection display section and a transmission display section, respectively;

a reflecting device is provided at least for said reflection display section; and

the thicknesses of the liquid crystal layer is relatively thinner in said reflection display section than in said transmission display section.

2. The liquid crystal display of claim 1, wherein an area of said reflection display accounts for at least 30% and at most 90% of a total area of said reflection display section and said transmission display section.

3. 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 shows dark display, said reflection display section also shows dark display.

4. The liquid crystal display of claim 3, 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 the dark display.

5. The liquid crystal display of claim 3, 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.

6. The liquid crystal display of claim 3, 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.

7. 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 relatively thicker than a region corresponding to said transmission display section.

8. The liquid crystal display of claim 1, wherein at least one of said pair of substrates includes an insulation film at least on a region corresponding to said reflection display section, said insulation film being relatively thicker in the region corresponding to said reflection display section than in the region corresponding to said transmission display section.

9. The liquid crystal display of claim 1, further comprising pressed coordinate detecting type input means, superimposed on a display surface, for, when pressed, detecting a pressed coordinate position.

10. The liquid crystal display of claim 9, wherein said polarization plate, said pressed coordinate detecting type input means, and said liquid crystal display element are provided in order.

11. The liquid crystal display of claim 1, wherein at least one phase difference compensation plate is used to change a polarization state, and wherein the changed polarization state is further changed by said liquid crystal layer, so that, when showing dark display, the polarization state on the reflection film is converted to circularly polarized light on the left or right.

12. The liquid crystal display of claim 1, wherein a phase difference compensation plate is provided to the outside of one of said pair of substrates, and two phase difference compensation plates are provided on the outside of the other one of the pair of substrates.