Liquid crystal light modulating device, and a manufacturing method and a manufacturing apparatus thereof

• US 6,459,467 B1
• Filed: 05/10/1999
• Issued: 10/01/2002
• Est. Priority Date: 05/15/1998
• Status: Active Grant

• Current Assignee: Minolta Corporation Limited (Konica Minolta Inc.)
• Original Assignee: Minolta Corporation Limited (Konica Minolta Inc.)
• Inventors: Nishiguchi, Kenji, Okada, Masakazu, Taniguchi, Tatsuo, Hashimoto, Kiyofumi
• Primary Examiner(s): Ton, Toan
• Application Number:
  US09/309,127
• Time in Patent Office: 1,240 Days
• Field of Search: 349/153, 349/189, 349/190, 349/155
• US Class Current: 349/153
• CPC Class Codes: B32B 17/10018 comprising only one glass sheet
• CPC Class Codes: B32B 17/10733 containing epoxy
• CPC Class Codes: B32B 17/10816 by pressing
• CPC Class Codes: B32B 17/10862 using pressing-rolls
• CPC Class Codes: B32B 2367/00 Polyesters, e.g. PET, i.e. polyethylene terephthalate
• CPC Class Codes: G02F 1/133305 Flexible substrates, e.g. plastics, organic film
• CPC Class Codes: G02F 1/1339 Gaskets; Spacers; Sealing of cells
• CPC Class Codes: G02F 1/1341 Filling or closing of cells
• CPC Class Codes: G02F 1/1347 Arrangement of liquid crystal layers or cells in which the final condition of one light beam is achieved by the addition of the effects of two or more layers or cells
• CPC Class Codes: G02F 1/13718 based on a change of the texture state of a cholesteric liquid crystal

Abstract

A liquid crystal display device which has a liquid crystal composition between a first substrate and a flexible second substrate. The liquid crystal composition is filled between the substrates by being dispensed on the first substrate and spread uniformly while the second substrate is being pressed against the first substrate by a roller, and the liquid crystal composition is sealed by sealing resin provided on the sides of the substrates. The gap between the substrates is maintained by spherical spacers and/or a resin structure.

Claims

1. A method of manufacturing a liquid crystal light modulating device including a first substrate and a second substrate, at least one of which is flexible, a liquid crystal material filled between the first and second substrates, and a seal surrounding the liquid crystal material to prevent the liquid crystal material from leaking, said method comprising the steps of:

(a) providing the seal on at least one of the first and second substrates, the step (a) including the steps of;

(a1) providing the seal which is not hardened on at least one of the first and second substrates; and

(a2) incompletely hardening the seal after the step (a1);

(b) dispensing the liquid crystal material onto the first substrate; and

(c) placing, after the execution of the steps (a) and (b), the second substrate onto the first substrate and hardening the seal to join the first and second substrates together.

2. A method as claimed in claim 1, wherein the seal is provided on the second substrate in the step (a).

3. A method as claimed in claim 1, wherein the seal is provided to continuously enclose a light modulating area in the step (a).

4. A method as claimed in claim 1, further comprising the step of:

(d) placing the first substrate on a support, wherein the step (b) is executed after the step (d).

5. A method as claimed in claim 1, wherein the step (b) comprises the steps of:

(b1) placing the first substrate onto a support; and

(b2) dispensing the liquid crystal material onto the first substrate placed on said support.

6. A method as claimed in claim 1, further comprising the step of:

(d) providing, before the step (c), a resin structure on at least one of the first and second substrates to be located in a light modulating area.

7. A method as claimed in claim 1, wherein the step (c) comprises the steps of:

(c1) pressing the first substrate against the second substrate;

(c2) heating the seal; and

(c3) cooling the seal after the step (c2).

8. A method as claimed in claim 7, wherein the steps (c2) and (c3) are executed during the step (c1).

9. A method as claimed in claim 7, wherein the seal is incompletely hardened by heat during the step (a2), and wherein a heating temperature during the step (a2) is lower than a heating temperature during the step (c2).

10. A method as claimed in claim 1, wherein the seal is incompletely hardened by heat during the step (a2).

11. A liquid crystal light modulating device comprising:

a first substrate and a second substrate, at least one of which is flexible;

a liquid crystal material filled between the first and second substrates; and

a seal surrounding the liquid crystal material to prevent the liquid crystal material from leaking;

wherein the liquid crystal light modulating device is manufactured by executing the steps of;

(a) providing the seal on at least one of the first and second substrates, the step (a) including the steps of;

(a1) providing the seal which is not hardened on at least one of the first and second substrates; and

(a2) incompletely hardening the seal after the step (a1);

(b) dispensing the liquid crystal material onto the first substrate; and

(c) placing, after the execution of the steps (a) and (b), the second substrate onto the first substrate and hardening the seal to join the first and second substrates together.

12. A liquid crystal light modulating device as claimed in claim 11, further comprising:

a resin structure located within a light modulating area of the first and second substrates, said resin structure having been provided on at least one of the first and second substrates before the step (c).

13. A liquid crystal light modulating device as claimed in claim 12, wherein said resin structure bonds the first and second substrates together.

14. A method of manufacturing a liquid crystal light modulating device including a first substrate and a second substrate, at least one of which is flexible, a liquid crystal material filled between the first and second substrates and a seal surrounding said liquid crystal material to prevent said liquid crystal material from leaking, said method comprising the steps of:

(a) providing the seal on the second substrate,

(b) dispensing the liquid crystal material on the first substrate;

(c) providing a plurality of resin-coated spacers on at least one of the first and second substrates to be located in a light modulating area; and

(d) placing, after the execution of the steps (a) through (c), the second substrate onto the first substrate and hardening the seal to join the first and second substrates together.

15. A method as claimed in claim 14, wherein the step (b) comprises the steps of:

(b1) placing the first substrate onto a support; and

(b2) dispensing the liquid crystal material onto the first substrate placed on said support.

16. A method as claimed in claim 14, wherein, in the step (d), said resin-coated spacers are provided on the second substrate.

17. A method of manufacturing a liquid crystal light modulating device including a first substrate and a second substrate, at least one of which is flexible, a liquid crystal material filled between the first and second substrates and a seal surrounding said liquid crystal material to prevent said liquid crystal material from leaking, said method comprising the steps of:

(a) forming an alignment layer on at least one of the first and second substrates inside of an area to be surrounded by the seal;

(b) providing the seal on the second substrate;

(c) dispensing the liquid crystal material on the first substrate; and

(d) placing, after the execution of the steps (a) through (c), the second substrate on the first substrate and hardening the seal to join the first and second substrates together.

18. A method of manufacturing a liquid crystal light modulating device including a first substrate and a second substrate, at least one of which is flexible, a liquid crystal material filled between the first and second substrates and a seal surrounding said liquid crystal material to prevent said liquid crystal material from leaking, said method comprising the steps of:

(a) providing the seal on at least one of the first and second substrates;

(b) providing a resin structure on at least one of the first and second substrates to be located in a light modulating area, said resin structure being made of a material identical to that of the seal;

(c) providing spacers on at least one of the first and second substrates;

(d) dispensing the liquid crystal material on at least one of the first and second substrates; and

(e) placing, after the execution of the steps (a) through (d), the second substrate on the first substrate and hardening the seal to join the first and second substrates together.

19. A method as claimed in claim 18, wherein the resin structure is provided on one of the first and second substrates, and wherein the seal is provided on the first or second substrate where the resin structure is provided.

20. A method as claimed in claim 18, wherein the resin structure and the seal are simultaneously provided on one of the first and second substrates.

21. A method as claimed in claim 20, wherein the process for providing the seal in the step (a) comprises a step of printing the material of the seal on at least one of the first and second substrates, and wherein the process for providing the resin structure in the step (b) comprises a step of printing the material of the resin structure on at least one of the first and second substrates.

22. A method as claimed in claim 18, wherein a process for providing the seal in the step (a) is equivalent to a process for providing the resin structure in the step (b).

23. A method of manufacturing a liquid crystal light modulating device including a first substrate and a second substrate, at least one of which is flexible, a liquid crystal material filled between the first and second substrates and a seal surrounding said liquid crystal material to prevent said liquid crystal material from leaking, said method comprising the steps of:

(a) providing the seal on the second substrate;

(b) providing a resin structure on the first substrate to be located in a light modulating area;

(c) dispensing the liquid crystal material onto at least one of the first and second substrates; and

(d) placing, after the execution of the steps (a) through (c), the second substrate onto the first substrate and hardening the seal to join the first and second substrates together.

24. A method as claimed in claim 23, wherein said resin structure is made of a thermoplastic resin material.

25. A method as claimed in claim 24, wherein a difference between a hardening temperature of the seal and a softening temperature of the resin structure is 15°

C. or less.

26. A method as claimed in claim 24, wherein, in the step (c), the resin structure is softened while the seal is hardened by heat.

27. A method as claimed in claim 23, wherein the resin structure is made of a material different from a material of the seal.

28. A method as claimed in claim 23, further comprising the step of:

(e) providing, before the step (d), spacers on at least one of the first and second substrates.

29. A method as claimed in claim 28, wherein said spacers are provided on the second substrate.

30. A method as claimed in claim 23, wherein said liquid crystal material is dispensed on the first substrate in the step (c).

31. A method of manufacturing a liquid crystal light modulating device including a first substrate and a second substrate, at least one of which is flexible, a liquid crystal material filled between the first and second substrates and a seal surrounding said liquid crystal material to prevent said liquid crystal material from leaking, said method comprising the steps of:

(a) providing the seal on at least one of the first and second substrates;

(b) providing a resin structure on the first substrate to be located in a light modulating area;

(c) providing spacers on the second substrate;

(d) dispensing the liquid crystal material onto at least one of the first and second substrates; and

(e) placing, after the execution of the steps (a) through (d), the second substrate onto the first substrate and hardening the seal to join the first and second substrates together.

32. A method as claimed in claim 31, wherein said seal is provided on the second substrate in the step (a).