Liquid crystal display and manufacturing method thereof

• US 6,864,945 B2
• Filed: 08/20/2001
• Issued: 03/08/2005
• Est. Priority Date: 08/30/2000
• 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: Narutaki, Yozo, Shinomiya, Tokihiko, Fujimori, Koichi
• Primary Examiner(s): Chowdhury, Tarifur R.
• Assistant Examiner(s): CHUNG, DAVID Y
• Application Number:
  US09/932,027
• Publication Number:
  US 20020075441A1
• Time in Patent Office: 1,296 Days
• Field of Search: 349/106, 349/110, 349/113, 349/122, 349/43, 349/155, 349/156, 349/157, 349/138, 349/123
• US Class Current: 349/156
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/13394 spacers regularly patterned on the cell subtrate, e.g. walls, pillars G02F1/133377 takes precedence

Abstract

A liquid crystal display has spacers for maintaining a liquid crystal layer and a cell gap between a substrate and an opposite substrate and also has regions either within a single pixel or over two or more pixels. The spacers are of columnar shape elongated from the substrate to the opposite substrate or the other way round, and the columnar spacers are provided in regions in which the liquid crystal layer is thinnest among those regions in which the liquid crystal layer varies in thickness. The structure makes the liquid crystal display having two or more different cell gaps to stably maintain those cell gaps and produces good quality displays.

Claims

1. A liquid crystal display with two opposing substrates sandwiching therebetween a liquid crystal layer variable in thickness either within a single pixel or from one pixel to another, said display comprising:

a plurality of columnar spacers between the two substrates where the liquid crystal layer is thinnest, the columnar spacers being elongated in a direction connecting the two substrates to maintain a cell gap;

one of the two substrates being provided with liquid crystal drive electrodes composed of reflection electrodes and transmission electrodes;

an interlayer insulation layer being provided on the substrate where the liquid crystal layer is thinnest; and

the reflection electrodes being provided on the interlayer insulation layer.

2. The liquid crystal display as defined in claim 1, wherein the reflection electrodes have a surface composed of an undulating part where incident light is scattered and a flat part which the columnar spacers contact.

3. The liquid crystal display as defined in claim 1, wherein

the liquid crystal layer has the largest thickness equal to a sum of a height of the columnar spacers and a thickness of the interlayer insulation layer.

4. The liquid crystal display as defined in claim 1, wherein:

there are provided a color filter layer and a black matrix layer on one of the two substrates; and

the columnar spacers are provided on the black matrix layer.

5. The liquid crystal display as defined in claim 4, wherein the columnar spacers are provided on blue filters in the color filter layer.

6. The liquid crystal display as defined in claim 4, wherein

the black matrix layer has apertures in which the columnar spacers are provided.

7. The liquid crystal display as defined in claim 4, wherein the columnar spacers are black.

8. The liquid crystal display as defined in claim 1, wherein the liquid crystal layer is made of a material exhibiting vertical alignment.

9. The liquid crystal display as defined in claim 1, wherein:

in a cross-section of a panel taken parallel to the two substrates, the columnar spacers account for 0.05% to 3.0% of the panel in area.

11. The liquid crystal display as defined in claim 4, wherein

the columnar spacers are provided on the black matrix layer so that a distance from an edge of the black matrix layer is longer than an extension of alignment defects that occur in proximity to the columnar spacers.

12. The liquid crystal display as defined in claim 4, wherein

a height of the columnar spacers is set so that a distance from an edge of the black matrix layer is longer than an extension of alignment defects that occur in proximity to the columnar spacers.

13. The liquid crystal display as defined in claim 4, wherein

the black matrix layer is subjected to a rubbing treatment;

and

a length of the black matrix layer in a direction of the rubbing treatment is longer than an extension of alignment defects that occur in proximity to the columnar spacers.

14. The liquid crystal display as defined in claim 13, wherein

the black matrix layer conceals not more than 20 μ

m from the columnar spacers toward an end point of the rubbing.

10. A liquid crystal display with two opposing substrates sandwiching therebetween a liquid crystal layer variable in thickness either within a single pixel or from one pixel to another, wherein:

a reflection section that reflects incident light is provided where the thickness of the liquid crystal layer is small, while a transmission section that transmits incident light is provided where the thickness of the liquid crystal layer is different from the thickness of the liquid crystal layer in the reflections section; and

there are provided columnar spacers on the reflection section between the two substrates, the columnar spacers being elongated in a direction connecting the two substrates to maintain a cell gap.