Method for manufacturing brightness enhancement film of liquid crystal display and structure thereof

• US 7,132,064 B2
• Filed: 01/20/2004
• Issued: 11/07/2006
• Est. Priority Date: 01/22/2003
• Status: Expired due to Fees

• Current Assignee: Optima Technology Corporation
• Original Assignee: Optima Technology Corporation
• Inventors: Wu, Long Hai, Wu, Pei Lun, Li, Tung Lung
• Primary Examiner(s): Vargot, Mathieu D.
• Application Number:
  US10/761,085
• Publication Number:
  US 20040150773A1
• Time in Patent Office: 1,022 Days
• Field of Search: 264/1.1, 264/1.36, 264/1.38, 264/1.7, 264/1.34, 428/1.1, 349/115
• US Class Current: 264/1.36
• CPC Class Codes: B29C 2035/0827 using UV radiation
• CPC Class Codes: B29C 2791/001 Shaping in several steps
• CPC Class Codes: B29C 35/0805 using electromagnetic radiation
• CPC Class Codes: B29K 2105/0079 Liquid crystals
• CPC Class Codes: B29K 2105/243 Partially cured
• CPC Class Codes: C09K 2323/03 Viewing layer characterised by chemical composition
• CPC Class Codes: G02B 5/3016 involving passive liquid crystal elements optical properties of liquid crystals G02F1/0063; polarising elements associated with active liquid crystal devices G02F1/133528
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer
• CPC Class Codes: G02F 1/133507 Films for enhancing the luminance
• CPC Class Codes: G02F 1/133606 including a specially adapted diffusing, scattering or light controlling members

Abstract

A method for manufacturing a brightness enhancement film of a liquid crystal display and a structure thereof are provided. The method includes: (a) providing a first substrate, (b) forming a first macromolecule liquid crystal on said first substrate, (c) curing a part of said first macromolecule liquid crystal on said first substrate for forming a first light transmitting layer, (d) providing a second substrate, (e) forming a second macromolecule liquid crystal on said second substrate, (f) curing a part of said second macromolecule liquid crystal on said second substrate for forming a second light transmitting layer, (g) combining a non-curing part of said first macromolecule liquid crystal and said second macromolecule liquid crystal for forming a third macromolecule liquid crystal between said first light transmitting layer and said second light transmitting layer, and (h) curing said third macromolecule liquid crystal for forming a third light transmitting layer.

Claims

1. A method for manufacturing a brightness enhancement film of a liquid crystal display (LCD) comprising steps of:

(a) providing a first substrate;

(b) forming a first macromolecule liquid crystal on said first substrate;

(c) curing a part of said first macromolecule liquid crystal on said first substrate for forming a first light transmitting layer;

(d) providing a second substrate;

(e) forming a second macromolecule liquid crystal on said second substrate;

(f) curing a part of said second macromolecule liquid crystal on said second substrate for forming a second light transmitting layer;

(g) combining a non-cured part of said first macromolecule liquid crystal and a non-cured part of said second macromolecule liquid crystal for forming a third macromolecule liquid crystal between said first light transmitting layer and said second light transmitting layer; and

(h) curing said third macromolecule liquid crystal for forming a third light transmitting layer.

2. A method according to claim 1 wherein said first substrate and said second substrate are polyethylene terephalate substrates (PET).

3. A method according to claim 1 wherein said first substrate and said second substrate each further comprises an alignment film.

4. A method according to claim 1 wherein said first macromolecule liquid crystal and second macromolecule liquid crystal are cholesteric liquid crystal (CLC).

5. A method according to claim 4 wherein the cholesterol molecules of said first light transmitting layer and said second light transmitting layer comprise a single pitch.

6. A method according to claim 4 wherein said first light transmitting layer and said second light transmitting layer have the same chiral character.

7. A method according to claim 1 wherein said step (b) is finished through coating.

8. A method according to claim 1 wherein said step (c) is finished through UV light which transmits said first substrate to cure a part of said first macromolecule liquid crystal.

9. A method according to claim 8 wherein said first substrate can absorb a part of said UV light.

10. A method according to claim 1 wherein said step (c) further comprises a step of:

(c1) providing a gas for said first macromolecule liquid crystal to control the curing thickness of said first macromolecule liquid crystal, wherein the quantity of said gas of said curing part of said first macromolecule liquid crystal is different from the quantity of said gas of a non-curing part of said first macromolecule liquid crystal.

11. A method according to claim 1 wherein said step (e) is finished through coating.

12. A method according to claim 1 wherein said step (f) is finished through UV light which transmits said second substrate to cure a part of said second macromolecule liquid crystal.

13. A method according to claim 12 wherein said second substrate can absorb a part of said UV light.

14. A method according to claim 1 wherein said step (f) further comprises a step of:

(f1) providing a gas for said second macromolecule liquid crystal to control the curing thickness of said second macromolecule liquid crystal, wherein the quantity of said gas of said curing part of said second macromolecule liquid crystal is different from the quantity of said gas of a non-curing part of said second macromolecule liquid crystal.

15. A method according to claim 1 wherein said step (g) further comprises a step of:

(g1) diffusing said first macromolecule liquid crystal and said second macromolecule liquid crystal after combining to make said third macromolecule liquid crystal spread equally between said first light transmitting layer and second light transmitting layer.

16. A method according to claim 1 wherein said step (h) further comprises a step of:

(h1) removing said second substrate.

17. A method for making brightness enhancement film, said method comprising steps of:

(a) providing a first substrate and a second substrate;

(b) forming a first and a second macromolecule liquid crystal on said first and said second substrate, respectively;

(c) curing a part of said first macromolecule liquid crystal on said first substrate and a part of said second macromolecule liquid crystal on said second substrate for forming a first light transmitting layer between said first substrate and said first macromolecule liquid crystal and forming a second light transmitting layer between said second substrate and said second macromolecule liquid crystal, respectively;

(d) combining a non-cured part of said first macromolecule liquid crystal and a non-cured part of said second macromolecule liquid crystal for forming a third macromolecule liquid crystal between said first light transmitting layer and said second light transmitting layer; and

(e) curing said third macromolecule liquid crystal for forming a third light transmitting layer.

18. A method according to claim 17 wherein step (c) further comprises a step of:

(c1) providing a gas for said macromolecule liquid crystal to control the curing thickness of said first and said second macromolecule liquid crystal, wherein the quantity of said gas of said curing part of said first and said second macromolecule liquid crystal is different from the quantity of said gas of a non-curing part of said first and said second macromolecule liquid crystal.

19. A method according to claim 17 wherein step (c) cures a part of said first and said second macromolecule liquid crystal under different temperature control, respectively.

20. A method according to claim 17 wherein step (d) further comprises a step of:

(d1) diffusing said first macromolecule liquid crystal and said second macromolecule liquid crystal after combining to make said third macromolecule liquid crystal spread equally between said first light transmitting layer and second light transmitting layer.

21. A method according to claim 17 wherein step (e) further comprises a step of:

(e1) removing said second substrate.

22. A method according to claim 17 wherein said second substrate is a ¼

-wavelength plate.