Capacitance substrate for a liquid crystal device and a projection type display device

• US 6,573,955 B2
• Filed: 03/15/2002
• Issued: 06/03/2003
• Est. Priority Date: 10/16/1996
• Status: Expired due to Term

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Murade, Masao
• Primary Examiner(s): CHOWDHURY, TARIFUR RASHID
• Application Number:
  US10/097,573
• Publication Number:
  US 20020118322A1
• Time in Patent Office: 445 Days
• Field of Search: 349/42, 349/43, 349/44, 349/139, 349/110, 349/111, 257/59, 257/72
• US Class Current: 349/44
• CPC Class Codes: G02F 1/136209 Light shielding layers, e.g. black matrix, incorporated in the active matrix substrate, e.g. structurally associated with the switching element

Abstract

Placement of a first light shielding film (7) at least below the channel region (1c) of a TFT which drives a pixel, and of a second light shielding film (3) above the same prevents impingement of light coming from above or from below on that channel region (1c). Further, a second light shielding film (3) is formed to cover the channel region (1c) and the first light shielding film (7), thereby to prevent the surface of the first light shielding film (7) from direct exposure to light.

Claims

1. A liquid crystal device, comprising:

a first non-pixel region formed in adjoining pixel electrodes;

a second non-pixel region formed in adjoining pixel electrodes, and crossing the first non-pixel region;

a data line formed along the first non-pixel region;

a scan line formed along the second non-pixel region;

a thin film transistor electrically connected to the data line and the scan line;

a first light-shielding member formed over at least a channel region of the thin film transistor, that extends along the first non-pixel region; and

a second light-shielding member formed under at least a channel region of the thin film transistor, that extends along the second non-pixel region;

wherein the second light-shielding member has at least an elongated protruding extension region formed in the first non-pixel region.

2. The liquid crystal device according to claim 1, the extension region formed in the first light-shielding member.

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

a capacitor electrode formed along the scan line.

4. The liquid crystal device according to claim 3, the second light-shielding film disposed in an area formed with the scan line and the capacitor electrode.

5. The liquid crystal device according to claim 1, the thin film transistor having a semiconductor layer which intersects the scan line twice.

6. The liquid crystal device according to claim 1, the first light-shielding member being the data line.

7. A projection type display device comprising:

a light source;

a liquid crystal device as recited in claim 1, that transmits or reflects light from the light source, after having modulated the light; and

a projection optical system which receives the modulated light from the liquid crystal device, and converges and enlarges it through projection.

8. A liquid crystal device, comprising:

a first non-pixel region formed in adjoining pixel electrodes;

a second non-pixel region formed in adjoining pixel electrodes, and crossing the first non-pixel region;

a data line formed along the first non-pixel region;

a scan line formed along the second non-pixel region;

a thin film transistor having a semiconductor layer which is routed to intersect the scan line twice, the thin film transistor being electrically connected to the data line and the scan line;

a first light-shielding member formed over at least a channel region of the thin film transistor, that extends along the first non-pixel region; and

a second light-shielding member formed under at least a channel region of the thin film transistor, that extends along the second non-pixel region, wherein the second light-shielding member has an extension region formed in the first non-pixel region.

9. The liquid crystal device according to claim 8, the extension region formed in the first light-shielding member.

10. The liquid crystal device according to claim 8, the first light-shielding member being the data line.

11. A projection type display device comprising:

a light source;

a liquid crystal device as recited in claim 8, that transmits or reflects light from the light source, after having modulated the light; and

a projection optical system which receives the modulated light from the liquid crystal device, and converges and enlarges it through projection.