Liquid crystal display device with optical shield film

• US 6,304,308 B1
• Filed: 08/09/1999
• Issued: 10/16/2001
• Est. Priority Date: 08/10/1998
• Status: Expired due to Term

• Current Assignee: Panasonic Liquid Crystal Display Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Hitachi Device Engineering Co., Ltd., Hitachi, Ltd.
• Inventors: Miyazawa, Toshio, Matsumoto, Katsumi, Saito, Katsutoshi, Takemoto, Iwao, Hirota, Syoichi
• Primary Examiner(s): Dudek, James A.
• Assistant Examiner(s): CHOWDHURY, TARIFUR RASHID
• Application Number:
  US09/370,245
• Time in Patent Office: 799 Days
• Field of Search: 349/153, 349/155, 349/156, 349/84, 349/110, 349/157
• US Class Current: 349/155
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• CPC Class Codes: G02F 1/13394 spacers regularly patterned on the cell subtrate, e.g. walls, pillars G02F1/133377 takes precedence
• CPC Class Codes: G02F 2203/02 reflective

Abstract

Eliminating differences in cell gap of a liquid crystal panel is effected to prevent display irregularities while avoiding contamination of the liquid crystal material due to unwanted contact of a seal material with the liquid crystal material. To this end, the liquid crystal panel includes a first substrate DSUB having multiple pixel electrodes AL-P in the form of a matrix, a second substrate USUB opposing the first substrate with a specified gap therebetween and having one or more transparent electrodes ITO-C, a liquid crystal layer LC made of a liquid crystal material sealed in the gap between the opposing substrates, and an alignment film on at least one of inner surfaces of the first and second substrates in contact with the liquid crystal layer for controlling alignment of the liquid crystal material. A plurality of pole-like spacers SPC-P are provided in a display area of the first substrate DSUB for retaining the gap between the first and second substrates DSUB, USUB at a predefined value while providing a band or strip-like spacer SPC-S that is made of the same material as that of the pole-like spacers and is formed to surround the display area and also has a width greater than the diameter of the pole spacers along with a sealing material SL filled along the outer edges of the strip spacer SPC-S for allowing the first substrate DSUB and the second substrate USUB to be tightly bonded together.

Claims

1. A liquid crystal display device comprising:

a first substrate having a display area, said display area having metallic pixel electrodes in the form of a matrix;

a second substrate having a transparent electrode opposing said first substrate with a gap between the first and second substrates;

a liquid crystal layer made of a liquid crystal material sealed in the gap between said first and second substrates;

an alignment layer on at least one of surfaces of said first and second substrates in contact with said liquid crystal layer for controlling alignment of said liquid crystal material;

a plurality of columnar spacers in said display area of said first substrate for retaining the gap between said first and second substrates;

an optical shield film provided outside of said display area and made of the same metallic layer as said metallic pixel electrodes, said optical shield film having a width greater than a width of each of said metallic pixel electrodes;

a zonal spacer surrounding said display area and being the same in material as said columnar spacers and having a width greater than a diameter of each columnar spacer and formed over said optical shield film; and

a sealing material filled at outer edges of said zonal spacer for adhesively fixing said first and second substrates together.

2. A liquid crystal display device according to claim 1, wherein said columnar spacers and said zonal spacer are made of a resist material.

3. A liquid crystal display device according to claim 1, wherein said columnar spacers and said zonal spacer are made of a photolithographically fabricated resist material.

4. A liquid crystal display device comprising:

a first substrate;

metallic pixel electrodes provided on said first substrate;

a display area comprising said pixel electrodes laid out in the form of a matrix;

a second substrate spatially opposing said first substrate with a gap therebetween;

a liquid crystal layer provided between the first and second substrates;

a plurality of pillar or pole-like spacers provided in the display area of said first substrate for keeping the gap between the substrates;

an optical shield film provided outside of said display area and made of the same metallic layer as said metallic pixel electrodes, said optical shield film having a width greater than a width of each of said metallic pixel electrodes;

a strip or band-like spacer surrounding said display area and being made of the same material as that of said pole-like spacers and formed over said optical shield film; and

a seal material formed at outer edges of said band-like spacer for allowing said first and second substrates to be immovably bonded together.

5. A liquid crystal display device according to claim 4, wherein said band-like spacer has its width greater than a diameter of said pole-like spacers.

6. A liquid crystal display device comprising:

a first substrate;

a matrix of rows and columns of reflective pixel electrodes on said first substrate;

a display area with said pixel electrodes provided therein;

an optical shield film made of the same metallic layer as said reflective pixel electrodes and being provided outside of said display area, said optical shield film having a width greater than a width of each of said reflective pixel electrodes;

a second substrate disposed opposite said first substrate with a gap therebetween;

a liquid crystal layer provided between the first and second substrates;

a columnar spacer formed over said first substrate and provided between two neighboring ones of the reflective pixel electrodes of said first substrate; and

a zonal spacer formed over the optical shield film at a location outside of said display area.

7. A liquid crystal display device according to claim 6, further comprising:

a seal material provided outside of said zonal spacer for adhesively fixing said first and second substrates together.