LCD having a shading layer exhibiting a different reflection characteristic from reflection electrodes

• US 5,708,486 A
• Filed: 09/16/1996
• Issued: 01/13/1998
• Est. Priority Date: 09/14/1995
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Sugawara, Saburo, Miyawaki, Mamoru
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): TON, MINH TOAN T
• Application Number:
  US08/714,436
• Time in Patent Office: 484 Days
• Field of Search: 349/110, 349/111, 349/113, 349/44
• US Class Current: 349/44
• CPC Class Codes: G02F 1/133553 Reflecting elements associated to illuminating devices G02F1/133605
• 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
• CPC Class Codes: G02F 1/136277 formed on a semiconductor substrate, e.g. of silicon

Abstract

A display unit comprises a first substrate having a display area including a plurality of reflection electrodes with a gap portion formed therebetween and a peripheral portion around the display area, a second substrate opposing the first substrate and having a transparent electrode, and a liquid crystal material being put between the first and second substrates. The first substrate has a shading layer at at least part of the gap portion and the peripheral portion. The shading layer exhibits a different reflection characteristic from the reflection electrodes.

Claims

1. A display unit comprising a first substrate having a display area including a plurality of reflection electrodes with a gap portion formed therebetween and a peripheral portion around the display area, a second substrate opposing said first substrate and having a transparent electrode, and a liquid crystal material being put between said first and second substrates, wherein said first substrate has a shading layer at at least part of said gap portion and said peripheral portion, and wherein said shading layer exhibits a different reflection characteristic from said reflection electrodes.

2. The display unit according to claim 1, wherein said first substrate has an insulation layer between said reflection electrodes and said shading layer to form a holding capacitor.

3. The display unit according to claim 1, wherein said shading layer is composed of a different material from said reflection electrodes to exhibit the different reflection characteristic.

4. The display unit according to claim 3, wherein said reflection electrodes are composed primarily of Al and said shading layer is composed primarily of a material selected from Ti, TiN, W and Mo.

5. The display unit according to claim 1, wherein said shading layer has a different surface roughness from said reflection electrodes to exhibit the different reflection characteristic.

6. The display unit according to claim 1, wherein said shading layer reflects light to a different direction from said reflection electrodes to exhibit the different reflection characteristic.

7. The display unit according to claim 6, wherein said shading layer has a different surface angle from said reflection electrode.

8. The display unit according to claim 7, wherein, let the angle between the surfaces of said reflection electrodes and the surface of said shading layer be θ

, let the refractive index of said liquid crystal material be n, and let the F-number of an optical projection system be F, and θ

satisfies any of the followings;

##EQU3##

9. The display unit according to claim 8, wherein said θ

is 10°

to 30°

.

10. The display unit according to claim 6, wherein said first substrate has a thick insulation layer under said reflection electrodes and a thin insulation layer at the gap portion.

11. The display unit according to claim 6, wherein said first substrate has a signal line in a plane below said reflection electrodes and a plurality of wiring layers with a gap space formed therebetween in the same plane as the signal line, and wherein said gap space is wider under said gap portion than under said reflection electrodes.

12. The display unit according to claim 6, wherein edges of said reflection electrodes adjoining each other are asymmetric to the pixel boundary plane therebetween.

13. The display unit according to claim 6, wherein said transparent electrode has a different angle from said reflection electrodes.

14. The display unit according to claim 6, wherein said first substrate has a plurality of scanning lines, a plurality of signal lines intersecting with said scanning lines, and a plurality of pixel switches located in the intersections of said scanning lines and said signal lines.