LIQUID CRYSTAL DISPLAY DEVICE AND METHOD FOR FABRICATING THE SAME

• US 20140016066A1
• Filed: 09/18/2013
• Published: 01/16/2014
• Est. Priority Date: 09/27/2000
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Takeda, Arihiro, Sasaki, Takahiro, Koike, Yoshio, Yoshida, Hidefumi, Inoue, Yuichi, Hanaoka, Kazutaka, Nakamura, Kimiaki, Fujikawa, Tetsuya, Takagi, Takashi, Inoue, Hiroyasu, Kataoka, Shingo, Seino, Tsutomu, Tanuma, Seji, Mayama, Takatoshi, Ochida, Hideo, Doi, Seiji
• Granted Patent: US 8,797,490 B2
• Time in Patent Office: Days
• US Class Current: 349/96
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/1337 Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
• 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 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G02F 1/139 based on orientation effects in which the liquid crystal remains transparent
• 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

In a liquid crystal display device, liquid crystal molecules are oriented in a vertical direction to the first substrate and the second substrate by the first molecule orientation film and the second molecule orientation film, respectively, in a non-driving state. A structural pattern is formed so as to extend in a first direction parallel to a surface of the liquid crystal layer and so as to form, in a driving state, an electric field periodically changing in a second direction that is parallel to the liquid crystal layer and vertical to the first direction. The liquid crystal molecules substantially tilt in the first direction in the driving state.

Claims

1. A liquid crystal display device comprising:

a first substrate;

a second substrate facing said first substrate;

a liquid crystal layer sealed between said first substrate and said second substrate;

a first electrode formed on said first substrate;

a second electrode formed on said second substrate;

a first molecule orientation film formed on said first substrate so as to cover said first electrode;

a second molecule orientation film formed on said second substrate so as to cover said second electrode;

a plurality of micro structures associated with at least one of the first and second electrodes, wherein at least some of said micro structures extend generally parallel to each other,

wherein when a driving voltage is applied between said first electrode and said second electrode, liquid crystal molecules of said liquid crystal layer are oriented such that no dark line occurs in a vicinity of said plurality of micro structures or between adjacent ones of said micro structures.

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

a polarizer provided outside of one of said first and second substrates, said polarizer having a light absorption axis P; and

an analyzer provided outside of the other of said first and second substrates, said analyzer having a light absorption axis A, wherein the light absorption axis A of said analyzer crosses the light absorption axis P of said polarizer,

wherein at least some of said micro structures extend in a direction that obliquely crosses at least one of said light absorption axis A of said analyzer and said light absorption axis P of said polarizer.

3. The liquid crystal display device according to claim 1, wherein in a non-driving state in which a driving voltage is not applied between said first electrode and said second electrode, liquid crystal molecules are oriented in a vertical direction to surfaces of said first and second substrates by said first molecule orientation film and said second molecule orientation film, respectively.

4. The liquid crystal display device as claimed in claim 1, wherein said liquid crystal layer comprises liquid crystal with negative inductive factor anisotropy.

5. The liquid crystal display device as claimed in claim 1, further comprising a plurality of rough structural patterns associated with at least one of the first and second substrates, wherein said rough structural patterns extend in directions different than the micro structures.

6. The liquid crystal display device according to claim 5, wherein said rough structural patterns comprise rough projection patterns.

7. The liquid crystal display device according to claim 5, wherein said rough structural patterns cross said micro structures.

8. The liquid crystal display device according to claim 7, wherein said rough structural patterns obliquely cross said micro structures.

9. The liquid crystal display device according to claim 7, wherein said micro structures extend in at least two different directions with respect to said micro structures.

10. The liquid crystal display device according to claim 7, wherein said rough structural patterns have a greater pitch and a larger width than said micro structures.

11. The liquid crystal display device according to claim 2, wherein the micro structures extend in four different directions that each slantingly cross the light absorption axis P of said polarizer and the light absorption axis A of said analyzer.

12. The liquid crystal display device according to claim 11, wherein the micro structures comprise micro-cutouts, and further wherein four different domains are defined by the micro structures that extend in four different directions.

13. The liquid crystal display device according to claim 5, wherein the micro structures comprise micro cutouts, and the micro cutouts extend in two different directions with respect to the rough structural patterns;

and further wherein liquid crystal molecules fall down in two different directions when a driving voltage is applied between the first and second electrodes, based on the two different directions of the micro-cutouts.

14. The liquid crystal display device according to claim 1, wherein an approximately 90 degree angle is defined between an orientation direction of liquid crystal molecules on one side of a domain border and liquid crystal molecules on the other side of the domain border.

15. The liquid crystal display device according to claim 2, wherein an approximately 45 degree angle is defined between the orientation direction of liquid crystal molecules on one side of the domain border and the light absorption axis P of said polarizer, and an approximately 45 degree angle is also defined between said liquid crystal molecules on the other side of the domain border and the light absorption axis P of said polarizer.

16. The liquid crystal display device according to claim 1, wherein a tilt direction of liquid crystal molecules, of said liquid crystal layer, in the presence of an applied voltage is controlled by an optical hardened material within said liquid crystal layer.