Liquid crystal display device

• US 7,133,108 B2
• Filed: 12/07/2001
• Issued: 11/07/2006
• Est. Priority Date: 12/08/2000
• Status: Expired due to Term

• Current Assignee: Panasonic Liquid Crystal Display Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Hitachi, Ltd.
• Inventors: Shimizu, Hiromasa, Hamamoto, Tatsuo
• Primary Examiner(s): Flynn, Nathan J.
• Assistant Examiner(s): Sefer, Ahmed N.
• Application Number:
  US10/004,805
• Publication Number:
  US 20020075443A1
• Time in Patent Office: 1,796 Days
• Field of Search: 349/156, 349/155, 349/106, 349/110
• US Class Current: 349/155
• CPC Class Codes: G02F 1/13394 spacers regularly patterned on the cell subtrate, e.g. walls, pillars G02F1/133377 takes precedence

Abstract

In order to prevent irreversible deformation of column-shaped spacers which retain the gap between a pair of substrates between which the liquid crystal layer of a liquid crystal display device is interposed, spacers which assist in preventing such irreversible deformation are newly provided. According to the invention, two or more kinds of spacers which differ in height from a reference surface are disposed on one of the pair of substrates. In addition, a step pattern with which the spacers are to come into contact is formed in advance on the other of the pair of substrates so that the heights of the spacers can be made different.

Claims

1. A liquid crystal display device comprising:

a first substrate on a main surface thereof, a black mask and color filters, each arranged in an aperture of the black mask, being formed;

a liquid crystal layer;

a second substrate disposed opposite to the first substrate across the liquid crystal layer and stuck to the first substrate by a sealing material applied to peripheries of a main surface of the first substrate facing the liquid crystal layer and of a main surface of the second substrate facing the liquid crystal layer;

a stacked structure formed on the main surface of the second substrate by stacking in order first signal lines, an insulating film covering the first signal lines, and second signal lines each overlappingly intersecting the first signal lines over the insulating film therebetween;

a plurality of pixel regions each formed as being surrounded by respective neighboring first signal lines and second signal lines, and having a pixel electrode; and

first spacers and second spacers both formed on the main surfaces of the first substrate, and arranged between pixel electrodes of adjacent pixel regions and in the liquid crystal layer,

wherein each of the second spacers is ordinarily spaced from the stacked structure formed on the second substrate to accommodate the liquid crystal layer therebetween, and each of the first spacers ordinarily contacts directly with the stacked structure formed on the second substrate,

wherein portions of the stacked structure contacting with the first spacers are thicker than other portions of the stacked structure corresponding to the second spacers with the liquid crystal layer interposed therebetween, and

wherein a distance between the stacked structure and each of the first spacers is longer than a distance between the stacked structure and each of the second spacers.

2. A liquid crystal display device according to claim 1, wherein each of the second spacers contacts with the stacked structure formed on the second substrate while the first spacers are subjected to an external force and elastically deformed.

3. A liquid crystal display device according to claim 1, wherein each of the first spacers contacts with the stacked structure at an overlappingly intersecting position of one of the first signal lines and one of the second signal lines, and

each of the second spacers contacts with another part of the stacked structure which includes one of the first signal lines but excludes any one of the second signal lines.

4. A liquid crystal display device according to claim 1, wherein the black mask and the color filters are covered by a protective film to bury steps formed by the black mask and the color filters, and the first spacers and the second spacers are formed on top of the protective film.

5. A liquid crystal display device, according to claim 1, wherein the second substrate has a plurality of pixels arranged on the main surface thereof, and each of the pixels has a switching element controlled by one of the first signal lines and a pixel electrode receiving a signal from one of the second signal lines through the switching element.

6. A liquid crystal display device comprising:

a first substrate including a black mask and color filters;

a liquid crystal layer;

a second substrate disposed opposite to the first substrate across the liquid crystal layer;

first signal lines formed on the second substrate;

second signal lines intersecting the first signal lines with an insulating film provided therebetween;

a plurality of pixel regions each formed as being surrounded by respective neighboring first signal lines and second signal lines, and having a pixel electrode;

a base pattern selectively formed between pixel electrodes of adjacent pixel regions;

a plurality of first spacers formed above a main surface of the first substrate and arranged above a first part where is between selected ones of said pixel electrodes of adjacent pixel regions and overlaps with the base pattern in a plan view; and

a plurality of second spacers formed on the main surface of the first substrate and arranged above a second part where is between other ones of said pixel electrodes of adjacent pixel regions and does not overlap with the base pattern in the plan view,

wherein each of the second spacers is ordinarily spaced from a stacked structure formed on the second substrate to accommodate the liquid crystal layer therebetween,

each of the first spacers is formed above the base pattern and ordinarily contacts directly the stacked structure formed on the second substrate,

the first part includes the base pattern,

the second part excludes the base pattern, and

the first part is disposed opposite to the second part across a respective pixel region in the plan view.

7. A liquid crystal display device, according to claim 6, wherein each of the second spacers contacts with the stacked structure formed on the second substrate, when the first spacers are subjected to an external force and elastically deformed.

8. A liquid crystal display device, according to claim 6, wherein the base pattern is covered by a protective film provided between the base pattern and the first spacers.