Chiral smectic liquid crystal device with different pretilt angles in pixel and non-pixel areas

• US 5,223,963 A
• Filed: 02/12/1992
• Issued: 06/29/1993
• Est. Priority Date: 02/13/1991
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Okada, Shinjiro, Inaba, Yutaka, Taniguchi, Osamu, Mizuno, Hironobu
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): GROSS, ANITA P
• Application Number:
  US07/834,391
• Time in Patent Office: 503 Days
• Field of Search: 359/76, 359/78, 359/100
• US Class Current: 349/129
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• CPC Class Codes: G02F 1/133753 with different alignment orientations or pretilt angles on a same surface, e.g. for grey scale or improved viewing angle
• CPC Class Codes: G02F 1/133761 with different pretilt angles
• CPC Class Codes: G02F 1/141 using ferroelectric liquid crystals

Abstract

A liquid crystal device comprising a first substrate on which a first group of belt-shaped electrodes are formed, a second substrate on which a second group of belt-shaped electrodes are formed so as to cross the first group of belt-shaped electrodes, and a chiral smectic liquid crystal arranged between the first and second substrates, wherein a first pretilt angle of the liquid crystal on the first group of belt-shaped electrodes differs from a second pretilt angle of the liquid crystal in the spaces between the belt-shaped electrodes.

Claims

1. A liquid crystal device having a first substrate on which a first group of belt-shaped electrodes are formed, a second substrate on which a second group of belt-shaped electrodes are formed so as to cross the first group of belt-shaped electrodes, and a chiral smectic liquid crystal arranged between the first and second substrates,

wherein a first pretilt angle of the liquid crystal on said first group of belt-shaped electrodes differs from a second pretilt angle of the liquid crystal in the spaces between the belt-shaped electrodes.

2. A liquid crystal device according to claim 1, wherein the first pretilt angle is larger than the ,, second pretilt angle.

3. A liquid crystal device according to claim 1, wherein the first and second pretilt angles are equal to or larger than 5°

.

4. A liquid crystal device according to claim 1, wherein the first pretilt angle is equal to or larger than 15°

and .the second pretilt angle lies within a range from 5°

to 15°

.

5. A liquid crystal device according to claim 1, wherein said chiral smectic liquid crystal has a structure such that a plurality of layers each of which is constructed by a plurality of molecules are arranged in the same direction so as to stand on the first and second substrates and that said layers are bent.

6. A liquid crystal device according to claim 1, wherein the liquid crystal on the second group of belt-shaped electrodes and the liquid crystal in the spaces among said belt-shaped electrodes further cause pretilt angles, and the pretilt angle of the liquid crystal on the second group of belt-shaped electrodes is larger than the pretilt angle of the liquid crystal in the spaces between said belt-shaped electrodes.

10. A display apparatus according to claim 1, wherein the chiral smectic liquid crystal has a structure such that a plurality of layers each of which is constructed by a plurality of molecules in the same direction so as to stand on the first and second substrates and that said layers are bent.

7. A display apparatus comprising:

a first substrate on which a first group of belt-shaped electrodes are formed, a second substrate on which a second group of belt-shaped electrodes are formed so as to cross the first group of belt-shaped electrodes, a liquid crystal panel having a chiral smectic liquid crystal arranged between said first and second substrates, and drive control means for driving and controlling the liquid crystal panel,

wherein a first pretilt angle of the liquid crystal on the first group of belt-shaped electrodes differs from a second pretilt angle of the liquid crystal in the spaces among said belt-shaped electrodes.

8. A display apparatus according to claim 7, wherein the first and second pretilt angles are equal to or larger than 5°

.

9. A display apparatus according to claim 7, wherein the first pretilt angle is equal to or larger than 15°

and the second pretilt angle lies within a range from 5°

to 15°

.