Liquid crystal display and electronic device

• US 20060203157A1
• Filed: 05/17/2006
• Published: 09/14/2006
• Est. Priority Date: 01/29/2002
• Status: Active Grant

• Current Assignee: BOE Technology Group Co., Ltd.
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Urano, Nobutaka, Maeda, Tsuyoshi, Ozawa, Kinya
• Granted Patent: US 7,671,941 B2
• Time in Patent Office: Days
• US Class Current: 349/114
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/133371 Cells with varying thickness of the liquid crystal layer
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/133776 having structures locally influencing the alignment, e.g. unevenness
• 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
• CPC Class Codes: G02F 2203/09 transflective

Abstract

The invention provides a liquid crystal display capable of obtaining light and high-contrast display having a wide viewing angle in a transflective liquid crystal display. A liquid crystal display of the present invention employs a vertical alignment mode using a liquid crystal layer that is vertically aligned in the initial alignment state. A transparent display area is disposed to surround the periphery of a reflective display area in one dot, and an insulating film is provided in the area that corresponds to the reflective display area in the center of the dot. The insulating film makes the thickness of the liquid crystal layer in the reflective display area to be smaller than the thickness of the liquid crystal layer in the transparent display area.

Claims

1. A liquid crystal display comprising:

a pair of substrates;

a liquid crystal layer sandwiched between the pair of substrates, the liquid crystal layer exhibiting vertical alignment in its initial alignment state;

a transparent display area for transparent display within a dot area;

a separate reflective display area for reflective display within the same dot area;

an insulating film between the liquid crystal layer and at least one of the pair of substrates, the insulating film making a thickness of the liquid crystal layer in the reflective display area smaller than a thickness of the liquid crystal layer in the transparent display area, the insulating film including an inclined area in the vicinity of the boundary between the reflective display area and the transparent display area, the inclined area having a continuously varying thickness that results in an inclined surface;

a transparent display area electrode to drive the liquid crystal layer at the transparent display area;

a reflective display area electrode to drive the liquid crystal layer at the reflective display area, at least one of the transparent display area electrode and the reflective display area electrode being in a complete non-overlapping condition with the inclined area of the insulating film; and

a connection portion that electrically connects the transparent display area electrode and the reflective display area electrode together, the connection portion being in overlap with the inclined area of the insulating film in plan view.

2. The liquid crystal display according to claim 1, the connection portion extending across the inclined area in a first direction, the connection portion having a narrower width than the transparent display area electrode or the reflective display area electrode in a second direction substantially perpendicular to the first direction.

3. A liquid crystal display comprising:

a pair of substrates;

a liquid crystal layer sandwiched between the pair of substrates, the liquid crystal layer exhibiting vertical alignment in its initial alignment state;

a transparent display area for transparent display within a dot area;

a separate reflective display area for reflective display within the same dot area;

an insulating film between the liquid crystal layer and at least one of the pair of substrates, the insulating film making a thickness of the liquid crystal layer in the reflective display area smaller than a thickness of the liquid crystal layer in the transparent display area, the insulting film including an inclined area in the vicinity of the boundary between the reflective display area and the transparent display area, the inclined area having a continuously varying thickness that results in an inclined surface;

a transparent display area electrode to drive the liquid crystal layer at the transparent display area;

a reflective display area electrode to drive the liquid crystal layer at the reflective display area, at least one of the transparent display area electrode and the reflective display area electrode at least partially overlapping with the inclined area of the insulating film; and

a connection portion that electrically connects the transparent display area electrode and the reflective display area electrode together, the connection portion being in overlap with the inclined area of the insulating film in plan view.

4. The liquid crystal display according to claim 3, at least one of the transparent display area electrode or the reflective display area electrode being at least partially in overlap with a portion of the inclined area in plan view.

5. The liquid crystal display according to claim 4, the at least one of the transparent display area electrode or the reflective display area electrode being in a non-overlapping condition with another portion of the inclined area in plan view.

6. The liquid crystal display according to claim 5, the connection portion being in overlap with the another portion of the inclined area in plan view.

7. The liquid crystal display according to claim 3, the connection portion extending across the inclined area in a first direction, the connection portion having a narrower width than the transparent display area electrode or the reflective display area electrode in a second direction substantially perpendicular to the first direction.