Liquid crystal device and electronic equipment

• US 7,148,939 B2
• Filed: 03/02/2004
• Issued: 12/12/2006
• Est. Priority Date: 04/01/2003
• Status: Active Grant

• Current Assignee: 138 East LCD Advancements Limited (Vector Capital Corporation)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Maeda, Tsuyoshi, Okazaki, Tsuyoshi, Ozawa, Kinya
• Primary Examiner(s): Schechter, Andrew
• Assistant Examiner(s): KIM, RICHARD H
• Application Number:
  US10/790,220
• Publication Number:
  US 20040196417A1
• Time in Patent Office: 1,015 Days
• Field of Search: 349/111, 349/117, 349/114
• US Class Current: 349/111
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• CPC Class Codes: G02F 1/133707 Structures for producing distorted electric fields, e.g. bumps, protrusions, recesses, slits in pixel electrodes
• CPC Class Codes: G02F 1/133742 for homeotropic alignment
• CPC Class Codes: G02F 1/1393 the birefringence of the liquid crystal being electrically controlled, e.g. ECB-, DAP-, HAN-, PI-LC cells G02F1/1396, G02F1/141 take precedence

Abstract

To achieve clear image display without providing a feeling of roughness by fixing the position where disclination is generated in a liquid crystal device of a homeotropic alignment type, a conductive light shielding film provided on the side of an opposed substrate as a common electrode to drive a liquid crystal layer by pixel electrodes of an array substrate and the light shielding film of the opposed substrate.

Claims

1. A liquid crystal device, comprising:

an array substrate including a plurality of pixel electrodes arranged in a matrix manner;

an opposed substrate including a conductive light shielding film having openings at positions opposing the pixel electrodes; and

a liquid crystal layer interposed between the substrates, the liquid crystal layer being formed of liquid crystal having negative dielectric anisotropy exhibiting homeotropic alignment in the initial alignment state, and the liquid crystal being controlled in alignment by an electric field developed by difference in electric potential between the pixel electrodes of the array substrate and the light shielding film of the opposed substrate.

2. The liquid crystal device according to claim 1, a projection or an opening formed on the pixel electrode.

3. The liquid crystal device according to claim 1, chiral material being added to the liquid crystal layer.

4. The liquid crystal device according to claim 1, the pixel electrode formed into a polygonal shape having no acute-angled portion.

5. The liquid crystal device according to claim 1, the shape of the pixel electrode being a regular polygon or a circle shape.

6. The liquid crystal device according to claim 1, further comprising:

a circular polarization injecting device to inject circular polarization onto the array substrate and the opposed substrate.

7. The liquid crystal device according to claim 1, a pixel pitch being 20 μ

n or below.

8. Electronic equipment, comprising:

the liquid crystal device according to claim 1.

9. The liquid crystal device according to claim 1, wherein the conductive light shielding film overlaps the pixel electrodes in plan view and surrounds a region of each of the pixel electrodes in plan view.

10. A liquid crystal device, comprising:

a pair of substrates;

a liquid crystal layer interposed between the substrates, the liquid crystal layer being formed of liquid crystal having a negative dielectric anisotropy exhibiting homeotropic alignment in the initial alignment state; and

a voltage applying device that applies voltage to the liquid crystal layer, the voltage applying device including a plurality of pixel electrodes arranged in a matrix and a conductive light shielding film, the pixel electrodes being disposed on one side of the liquid crystal layer and the light shielding film being disposed on the other side of the liquid crystal layer, the pixel electrode being selectively applied with voltage and the light shielding film being applied with a voltage to selectively develop an electric field between the pixel electrode and the light shielding film for controlling alignment of the liquid crystal, the light shielding film having openings at positions opposing the pixel electrodes.

11. The liquid crystal device according to claim 10, wherein the conductive light shielding film overlaps the pixel electrodes in plan view and surrounds a region of each of the pixel electrodes in plan view.