LIQUID CRYSTAL DISPLAY AND MANUFACTURING METHOD THEREOF

• US 20150029455A1
• Filed: 06/13/2014
• Published: 01/29/2015
• Est. Priority Date: 07/24/2013
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: KIM, Su Jeong, KWON, Oh Jeong, SHIN, Ki Chul
• Granted Patent: US 10,317,734 B2
• Time in Patent Office: Days
• US Class Current: 349/129
• CPC Class Codes: G02F 1/133726 made of a mesogenic material
• 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 1/133773 the alignment material or treatment being different for the two opposite substrates
• CPC Class Codes: G02F 1/133788 by light irradiation, e.g. linearly polarised light photo-polymerisation

Abstract

A liquid crystal display includes a thin film transistor panel including a first alignment layer, an opposing panel including a second alignment layer, and opposite to the thin film transistor panel, and a liquid crystal layer between the thin film transistor panel and the opposing panel, and including liquid crystal molecules, wherein a difference between a pretilt angle provided by the first alignment layer and a pretilt angle provided by the second alignment layer is equal to or greater than about 0.8 degree.

Claims

1. A liquid crystal display, comprising:

a thin film transistor panel including a first alignment layer;

an opposing panel including a second alignment layer, and opposite to the thin film transistor panel; and

a liquid crystal layer between the thin film transistor panel and the opposing panel, and including liquid crystal molecules;

wherein a difference between a pretilt angle provided by the first alignment layer and a pretilt angle provided by the second alignment layer is equal to or greater than about 0.8 degree.

2. The liquid crystal display of claim 1, wherein:

the first alignment layer and the second alignment layer include a same alignment material.

3. The liquid crystal display of claim 2, wherein:

the first alignment layer includes a first alignment adjusting layer and a first pretilt adjusting layer, and

the second alignment layer includes a second alignment adjusting layer and a second pretilt adjusting layer,

wherein the first pretilt adjusting layer defines a thin film transistor panel-side pretilt angle of the liquid crystal molecules, and the second pretilt adjusting layer defines an opposing panel-side pretilt angle of the liquid crystal molecules.

4. The liquid crystal display of claim 3, wherein:

the opposing panel-side pretilt angle is smaller than the thin film transistor panel-side pretilt.

5. The liquid crystal display of claim 3, wherein:

the first and second alignment adjusting layers include a polymer including a vertical alignment material, and

the first and second pretilt adjusting layers include polymers including reactive mesogen.

6. The liquid crystal display of claim 5, wherein:

the thin film transistor panel further includes a pixel electrode including a plurality of fine branch portions, and

the polymers including the reactive mesogen of the first and second pretilt adjusting layers are arranged in a direction of the plurality of fine branch portions.

7. The liquid crystal display of claim 1, further comprising:

a curved display panel including the thin film transistor panel and the opposing panel.

8. A method of manufacturing a liquid crystal display, the method comprising:

manufacturing a thin film transistor panel, and an opposing panel opposite to the thin film transistor panel;

applying an alignment material onto each of the thin film transistor panel and the opposing panel;

forming alignment layers by curing the alignment material of each of the thin film transistor panel and the opposing panel;

exposing only one of the thin film transistor panel and the opposing panel to ultraviolet rays;

forming a liquid crystal layer and bonding the thin film transistor panel and the opposing panel; and

exposing the bonded panels to an ultraviolet ray electric field.

9. The method of claim 8, wherein:

a difference between a pretilt angle provided by the alignment layer on the thin film transistor panel and a pretilt angle provided by the alignment layer on the opposing panel is equal to or greater than about 0.8 degree.

10. The method of claim 9, wherein:

the applying the alignment material includes applying a same alignment material including reactive mesogen onto each of the thin film transistor panel and the opposing panel.

11. The method of claim 10, wherein:

the opposing panel is exposed to the ultraviolet rays.

12. The method of claim 10, wherein:

the alignment layers include an alignment adjusting layer and a pretilt adjusting layer.

13. The method of claim 10, wherein:

the exposing only one of the thin film transistor panel and the opposing panel to ultraviolet rays includes exposing only one of the thin film transistor panel and the opposing panel to ultraviolet rays with an intensity of approximately 5 joules per square centimeter to approximately 30 joules per square centimeter for about 20 minutes to about 1 hour.

14. The method of claim 10, further comprising:

baking the thin film transistor panel and the opposing panel at different temperatures, respectively, before the forming the liquid crystal layer and the bonding of the thin film transistor panel and the opposing panel.

15. A method of manufacturing a liquid crystal display, the method comprising:

manufacturing a thin film transistor panel, and an opposing panel opposite to the thin film transistor panel;

applying an alignment material onto each of the thin film transistor panel and the opposing panel;

forming alignment layers by curing the alignment material of each of the thin film transistor panel and the opposing panel, in which the thin film transistor panel and the opposing panel are baked at different temperatures, respectively;

forming a liquid crystal layer and bonding the thin film transistor panel and the opposing panel; and

exposing the bonded panels to an ultraviolet ray electric field.

16. The method of claim 15, wherein:

a difference between a pretilt angle provided by the alignment layer on the thin film transistor panel and a pretilt angle provided by the alignment layer on the opposing panel is equal to or greater than about 0.8 degree.

17. The method of claim 16, wherein:

the applying the alignment material includes applying a same alignment material including reactive mesogen onto each of the thin film transistor panel and the opposing panel.

18. The method of claim 17, wherein:

the forming the alignment layers includes differentiating pre-curing temperatures for the alignment materials of the thin film transistor panel and the opposing panel, respectively.

19. The method of claim 17, wherein:

the forming the alignment layers includes differentiating main-curing temperatures for the alignment materials of the thin film transistor panel and the opposing panel, respectively.

20. The method of claim 17, wherein:

the forming the alignment layers includes differentiating pre-curing temperatures and main-curing temperatures for the alignment materials of the thin film transistor panel and the opposing panel, respectively.

21. The method of claim 17, wherein:

the alignment material applied onto the opposing panel is subjected to pre-curing at a lower temperature than that of the alignment material applied onto the thin film transistor panel.

22. The method of claim 17, wherein:

the alignment material applied onto the opposing panel is subjected to main-curing at a higher temperature than that of the alignment material applied onto the thin film transistor panel.

23. The method of claim 15, wherein:

the alignment layers include an alignment adjusting layer and a pretilt adjusting layer.

24. The method of claim 15, further comprising:

exposing only one panel among the thin film transistor and opposing panels to ultraviolet rays before the forming the liquid crystal layer and the bonding the thin film transistor panel and an opposing panel.