Liquid crystal device and process for producing same

• US 5,936,694 A
• Filed: 04/24/1996
• Issued: 08/10/1999
• Est. Priority Date: 04/26/1995
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Shimamune, Masayuki, Nakai, Noriyuki, Suzuki, Masaaki
• Primary Examiner(s): Nguyen, Tiep H.
• Application Number:
  US08/637,034
• Time in Patent Office: 1,203 Days
• Field of Search: 349/106, 349/108, 349/139, 349/142, 349/143, 349/151, 349/152, 349/109
• US Class Current: 349/151
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/133388 with constructional differences between the display region and the peripheral region
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/134336 Matrix

Abstract

A liquid crystal device is constituted by disposing a liquid crystal between a pair of substrates each provided with an electrode to provide an effective optical modulation region and a peripheral region. At least one substrate of the pair of substrates comprises an intermediate layer disposed between the substrate and the electrode in the effective optical modulation region and the peripheral region, and the electrode on the intermediate layer comprises a first electrode disposed at least in the effective optical modulation region and a second electrode disposed in the peripheral region. The first and second electrodes are separated from each other. The intermediate layer may preferably include a color filter, a light-interrupting layer and a coating layer.

Claims

1. A liquid crystal device, comprising:

first and second substrates disposed opposite to each other so as to provide a rectangular cell structure having four sides, the first substrate being provided with a first electrode structure and the second substrate being provided with a second electrode structure, and

a liquid crystal disposed between said first and second substrates to provide an effective optical modulation region and a peripheral region along at least two sides of the cell structure outside the effective optical modulation region, wherein

said first substrate is further provided with an intermediate layer disposed between said first substrate and said first electrode structure in the effective optical region and the peripheral region, and

said first electrode structure on the intermediate layer comprises a first electrode disposed at least in the effective optical modulation region and a second electrode disposed in the peripheral region, the first and second electrodes being spaced apart from each other,

wherein the intermediate layer comprises a color filter film comprising at least one color segment and a coating later disposed on the color filter film and is disposed on one of the first and second substrates.

2. A device according to claim 1, wherein the first electrode has a pattern corresponding to plural display pixels in the effective optical modulation region as a display region.

3. A device according to claim 1, wherein the color filter film comprises at least three color filter segments comprising a red color filter segment, a green color filter segment, and a blue color filter segment.

4. A device according to claim 1, wherein the intermediate layer further comprises a light-interrupting layer disposed so as to fill a space between a prescribed number of color filter segments in the effective optical modulation region.

5. A device according to claim 1, wherein the intermediate layer further comprises a light-interrupting layer disposed so as to fill a space between a prescribed number of color filter segments in the effective optical modulation region and the peripheral region.

6. A device according to claim 1, wherein the color filter film comprises a first color filter film in the effective optical modulation region and a second color filter film in the peripheral region, the second color filter film comprising at least one color filter segment each of which is larger in size than that of at least one color filter segment constituting the first color filter film.

7. A device according to claim 1, wherein the first and second electrode structures comprise an electroconductive transparent material.

8. A device according to claim 1, wherein the first and second substrates are connected to each other with a sealing agent at a periphery portion therebetween to provide a prescribed cell gap, and the second electrode extends under the sealing agent.

9. A device according to claim 8, wherein the prescribed cell gap is a cell gap of at most 5 μ

m.

10. A device according to claim 1, wherein the first electrode and the second electrode have different patterns.

11. A device according to claim 1, wherein the second electrode disposed in the peripheral region is not supplied with a voltage.

12. A device according to claim 1, wherein the liquid crystal comprises a chiral smectic liquid crystal.

13. A device according to claim 1, wherein the second electrode is permanently electrically isolated from the first electrode.

14. A device according to claim 1, wherein the second electrode is disposed in a floating state.

15. A device according to claim 1, wherein the effective optical modulation region includes a plurality of pixels with spacings therebetween.

16. A process for producing a liquid crystal device comprising first and second substrates disposed opposite to each other so as to provide a rectangular cell structure having four sides, the first substrate being provided with a first electrode structure and the second substrate being provided with a second electrode structure, and a liquid crystal disposed between the first and second substrates to provide an effective optical modulation region and a peripheral region along at least two sides of the cell structure outside the effective optical modulation region, said process including the steps of:

forming an intermediate layer on at least the first substrate in the effective optical region and the peripheral region, and

forming, on the intermediate layer, the first electrode structure including an electrode having a first electrode pattern in the effective optical modulation region and a second electrode pattern in the peripheral region through a photolithographic process and an etching with an etchant, wherein the first electrode pattern and the second electrode pattern are spaced apart from each other,

wherein the intermediate layer comprises a color filter film comprising at least one color segment and a coating later disposed on the color filter film and is disposed on one of the first and second substrates.

17. A process according to claim 16, wherein the etchant comprises a mixture solution of hydroiodic acid and ferric chloride or a mixture solution of hydrochloric acid and ferric chloride.

18. A process according to claim 16, wherein the step of forming the intermediate layer includes the steps of:

forming a color filter film comprising at least one color filter segment on the first substrate, and

forming a coating layer on the color filter film.

19. A process according to claim 16, wherein the step of forming the intermediate layer includes the steps of:

forming a color filter film comprising at least one color filter segment on the first substrate,

forming a light-interrupting layer so as to fill a space between a prescribed number of color filter segments in the effective optical region and the peripheral region, and

forming a coating layer on the light-interrupting layer and the color filter film.

20. A process according to claim 16, wherein the first electrode pattern and the second electrode pattern are separated from each other.

21. A process according to claim 17, wherein the effective optical modulation region includes a plurality of pixels with spacings therebetween.

22. A liquid crystal device, comprising first and second substrates, the first substrate being provided with a first electrode structure and the second substrate being provided with a second electrode structure, and a liquid crystal disposed between said first and second substrates to provide an effective optical modulation region and a peripheral region, wherein

the first substrate has an effective optical modulation region and has a peripheral region including a first region and a second region disposed opposite each other via the effective optical modulation region, and

the first electrode structure has a first pattern in the form of stripes extending from the effective optical modulation region to an outside portion via the second region to be connected with an external drive unit and has a second pattern in the first region apart from the first pattern and functionally separate from the first pattern.

23. A device according to claim 22, wherein the second pattern comprises plural independent portions each of which is located in an extending direction of the corresponding stripe of the first pattern.

24. A device according to claim 22, wherein the first electrode structure is formed on the first substrate via an intermediate layer disposed in the effective optical modulation region and the first and second regions of the peripheral region.

25. A device according to claim 24, wherein the intermediate layer comprises a color filter film comprising at least one color filter segment, and in the effective optical modulation region, the first and second electrode structures have stripe patterns intersecting with each other to constitute plural display pixels.

26. A device according to claim 25, wherein the color filter film comprises at least three color filter segments comprising a red color filter segment, a green color filter segment, and a blue color filter segment.

27. A device according to claim 25, wherein the intermediate layer further comprises a light-interrupting layer disposed so as to fill a space between a prescribed number of color filter segments in the effective optical modulation region.

28. A device according to claim 25, wherein the intermediate layer further comprises a light-interrupting layer disposed so as to fill a space between a prescribed number of color filter segments in the effective optical modulation region and the first region of the peripheral region.

29. A device according to claim 28, wherein, in the effective optical modulation region, the first and second electrode structures have stripe patterns intersecting with each other to constitute plural display pixels.

30. A device according to claim 22, wherein the first and second electrode structures comprise an electroconductive transparent material.

31. A device according to claim 22, wherein the electrode having the second pattern is not supplied with a voltage in the first region.

32. A device according to claim 22, wherein the liquid crystal device has a cell gap of at most 5 μ

m.

33. A device according to claim 22, wherein the liquid crystal comprises a chiral smectic liquid crystal.