Liquid crystal display with light transmission regions and light reflection regions

• US 7,151,581 B2
• Filed: 08/04/2005
• Issued: 12/19/2006
• Est. Priority Date: 12/26/1997
• Status: Expired due to Fees

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Shimada, Takayuki, Kubo, Masumi, Ishii, Yutaka, Ban, Atsushi, Yoshimura, Youji, Narutaki, Yozo, Maruyama, Yuko, Yamakawa, Shinya, Katayama, Mikio, Fujioka, Shogo
• Primary Examiner(s): CHOWDHURY, TARIFUR RASHID
• Application Number:
  US11/196,749
• Publication Number:
  US 20050270455A1
• Time in Patent Office: 502 Days
• Field of Search: 349/114
• US Class Current: 349/114
• CPC Class Codes: G02F 1/133371 Cells with varying thickness of the liquid crystal layer
• CPC Class Codes: G02F 1/133504 Diffusing, scattering, diffracting elements associated to illuminating devices G02F1/133606
• CPC Class Codes: G02F 1/133553 Reflecting elements associated to illuminating devices G02F1/133605
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/133557 Half-mirrors
• CPC Class Codes: G02F 1/133638 Waveplates, i.e. plates with a retardation value of lambda/n
• 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 1/13712 the liquid crystal having negative dielectric anisotropy
• CPC Class Codes: G02F 2203/09 transflective

Abstract

A liquid crystal display device includes a first substrate; a second substrate; a liquid crystal layer interposed between the first substrate and the second substrate; a first polarizer provided on a surface of the first substrate which is on the opposite side to the liquid crystal layer; a second polarizer provided on a surface of the second substrate which is on the opposite side to the liquid crystal layer; a first phase compensation element provided between the first polarizer and the liquid crystal layer; and a second phase compensation element provided between the second polarizer and the liquid crystal layer. A plurality of pixel areas are provided for display. The first substrate includes at least one transmissive electrode, and the second substrate includes a reflective electrode region and a transmissive electrode region in correspondence with each of the plurality of pixel areas.

Claims

1. A liquid crystal display device comprising:

a first substrate and a second substrate;

a liquid crystal layer interposed between at least the first substrate and the second substrate;

wherein the first substrate includes a plurality of gate lines, a plurality of source lines arranged substantially orthogonal to the plurality of gate lines, a plurality of switching elements disposed in the vicinity of crossings of the gate lines and source lines, and a plurality of pixel electrodes electrically connected to the plurality of switching elements;

wherein the second substrate includes a counter electrode;

a plurality of pixel regions are formed via at least the plurality of pixel electrodes, the counter electrode and the liquid crystal layer interposed between the plurality of pixel electrodes and the counter electrode;

wherein each of the plurality of pixel regions includes a reflection region and a transmission region, wherein light reflected in the reflection regions and light transmitted through the transmission regions are utilized in displaying an image;

wherein the first substrate includes a reflection electrode region provided in at least the reflection region and a transmission electrode region provided in at least the transmission region;

wherein the reflection electrode region is higher than the transmission electrode region, forming a step on a surface of the first substrate, and thus a thickness of the liquid crystal layer in the reflection region is smaller than a thickness of the liquid crystal layer in the transmission; and

wherein a reflection layer of the reflection electrode region is at least partially formed on an interlayer insulating film, and the interlayer insulating film has a plurality of round protrusions on a surface thereof.

2. The liquid crystal display device of claim 1, wherein the transmission region is substantially rectangular in shape.

3. The liquid crystal display device of claim 1, wherein the reflection region entirely surrounds the transmission region on all sides as viewed from above.

4. A liquid crystal display device comprising:

a first substrate and a second substrate;

a liquid crystal layer interposed between at least the first substrate and the second substrate;

wherein the first substrate includes a plurality of gate lines, a plurality of source lines arranged substantially orthogonal to the plurality of gate lines, a plurality of switching elements disposed in the vicinity of crossings of the gate lines and source lines, and a plurality of pixel electrodes electrically connected to the plurality of switching elements;

wherein the second substrate includes a counter electrode;

a plurality of pixel regions are formed via at least the plurality of pixel electrodes, the counter electrode and the liquid crystal layer interposed between the plurality of pixel electrodes and the counter electrode;

wherein each of the plurality of pixel regions includes a reflection region and a transmission region, wherein light reflected in the reflection regions and light transmitted through the transmission regions are utilized in displaying an image;

wherein the first substrate includes a reflection electrode region provided in at least the reflection region and a transmission electrode region provided in at least the transmission region;

wherein the reflection electrode region is higher than the transmission electrode region, forming a step on a surface of the first substrate, and thus a thickness of the liquid crystal layer in the reflection region is smaller than a thickness of the liquid crystal layer in the transmission region; and

wherein in at least one pixel region;

the reflection region includes a reflection layer including a surface comprising concave and/or convex portions;

the reflection region substantially surrounds the transmission region; and

in the pixel region a shortest distance between the transmission region and a first bus line corresponding to the pixel region is less than a shortest distance between the transmission region and a second bus line corresponding to the pixel region.

5. The liquid crystal display device of claim 4, wherein the transmission region is located in a central portion of the pixel region.

6. The liquid crystal display device of claim 4, wherein the reflection layer is at least partially formed on an interlayer insulating film.

7. The liquid crystal display device of claim 6, wherein the interlayer insulating film has a wave-like upper surface.

8. The liquid crystal display device of claim 6, wherein the interlayer insulating film has a plurality of round protrusions on a surface thereof.

9. The liquid crystal display device of claim 6, wherein the interlayer insulating film comprises a layer comprising organic resin material.

10. The liquid crystal display device of claim 6, wherein the switching elements are thin film transistors.

11. A liquid crystal display device comprising:

a first substrate and a second substrate;

a liquid crystal layer interposed between at least the first substrate and the second substrate;

wherein the first substrate includes a plurality of gate lines, a plurality of source lines arranged substantially orthogonal to the plurality of gate lines, a plurality of switching elements disposed in the vicinity of intersections of the gate lines and source lines, and a plurality of pixel electrodes electrically connected to the plurality of switching elements;

wherein the second substrate includes a counter electrode;

a plurality of pixel regions are formed via at least the plurality of pixel electrodes, the counter electrode and the liquid crystal layer interposed between the plurality of pixel electrodes and the counter electrode;

wherein each of the plurality of pixel regions includes a reflection region and a transmission region, wherein light reflected in the reflection regions and light transmitted through the transmission regions are utilized in displaying an image;

wherein in at least one of the pixel regions the first substrate includes a reflection electrode region provided in at least the reflection region and a transmission electrode region provided in at least the transmission region, and wherein at least one of the pixel electrodes of the first substrate includes a reflection electrode in the reflection electrode region and a transmission electrode in the transmission electrode region where the reflection electrode is located over the transmission electrode; and

wherein the reflection electrode is at least partially formed on an interlayer insulating film, and the interlayer insulating film has a plurality of round protrusions on a surface thereof.

12. The liquid crystal display device of claim 11, wherein the transmission region is substantially rectangular in shape.

13. The liquid crystal display device of claim 11, wherein the reflection region entirely surrounds the transmission region on all sides as viewed from above.

14. A liquid crystal display device comprising:

a first substrate and a second substrate;

a liquid crystal layer interposed between at least the first substrate and the second substrate;

wherein the first substrate includes a plurality of gate lines, a plurality of source lines arranged substantially orthogonal to the plurality of gate lines, a plurality of switching elements disposed in the vicinity of intersections of the gate lines and source lines, and a plurality of pixel electrodes electrically connected to the plurality of switching elements;

wherein the second substrate includes a counter electrode;

a plurality of pixel regions are formed via at least the plurality of pixel electrodes, the counter electrode and the liquid crystal layer interposed between the plurality of pixel electrodes and the counter electrode;

wherein each of the plurality of pixel regions includes a reflection region and a transmission region, wherein light reflected in the reflection regions and light transmitted through the transmission regions are utilized in displaying an image;

wherein in at least one of the pixel regions the first substrate includes a reflection electrode region provided in at least the reflection region and a transmission electrode region provided in at least the transmission region, and wherein at least one of the pixel electrodes of the first substrate includes a reflection electrode in the reflection electrode region and a transmission electrode in the transmission electrode region where the reflection electrode is located over the transmission electrode; and

wherein in at least one pixel region;

the reflection region includes a reflection layer including a surface comprising concave and/or convex portions;

the reflection region substantially surrounds the transmission region; and

in the pixel region a shortest distance between the transmission region and a first bus line corresponding to the pixel region is less than a shortest distance between the transmission region and a second bus line corresponding to the pixel region.

15. The liquid crystal display device of claim 14, wherein the transmission region is located in a central portion of the pixel region.

16. The liquid crystal display device of claim 14, wherein the reflection electrode is at least partially formed on an interlayer insulating film.

17. The liquid crystal display device of claim 16, wherein the interlayer insulating film has a wave-like upper surface.

18. The liquid crystal display device of claim 16, wherein the interlayer insulating film has a plurality of round protrusions on a surface thereof.

19. The liquid crystal display device of claim 16, wherein the interlayer insulating film comprises a layer comprising organic resin material.

20. The liquid crystal display device of claim 16, wherein the switching elements are thin film transistors.

21. A liquid crystal display device for displaying an image including a plurality of pixels, the device comprising:

a first substrate, a second substrate, and a liquid crystal layer interposed between at least the first substrate and the second substrate, a pixel region corresponding to one of the plurality of pixels;

wherein the pixel region includes a reflection region having light reflectivity and a transmission region having light transmissivity;

wherein reflected light from the reflection region and transmitted light from the transmission region are utilized in displaying the image;

a thickness of the liquid crystal layer in the transmission region is larger than a thickness of the liquid crystal layer in the reflection; and

wherein a reflection layer of the reflection region is at least partially formed on an interlayer insulating film, and the interlayer insulating film has a plurality of round protrusions on a surface thereof.

22. The liquid crystal display device of claim 21, wherein the transmission region is substantially rectangular in shape.

23. The liquid crystal display device of claim 21, wherein the reflection region entirely surrounds the transmission region on all sides as viewed from above.

24. A liquid crystal display device for displaying an image including a plurality of pixels, the device comprising:

a first substrate, a second substrate, and a liquid crystal layer interposed between at least the first substrate and the second substrate, a pixel region corresponding to one of the plurality of pixels;

wherein the pixel region includes a reflection region having light reflectivity and a transmission region having light transmissivity;

wherein reflected light from the reflection region and transmitted light from the transmission region are utilized in displaying the image;

a thickness of the liquid crystal layer in the transmission region is larger than a thickness of the liquid crystal layer in the reflection region; and

wherein in at least one pixel region;

the reflection region includes a reflection layer including a surface comprising concave and/or convex portions;

a first of the reflection region and the transmissive region substantially surrounds the other of the reflection region and the transmission region, and in the pixel region a shortest distance between the other of the reflection region and the transmission region and a first bus line corresponding to the pixel region is less than a shortest distance between the other of the reflection region and the transmission region and a second bus line corresponding to the pixel region.

25. The liquid crystal display device of claim 24, wherein the transmission region is located in a central portion of the pixel region.

26. The liquid crystal display device of claim 24, wherein the reflection layer is at least partially formed on an interlayer insulating film.

27. The liquid crystal display device of claim 26, wherein the interlayer insulating film has a wave-like upper surface.

28. The liquid crystal display device of claim 26, wherein the interlayer insulating film has a plurality of round protrusions on a surface thereof.

29. The liquid crystal display device of claim 26, wherein the interlayer insulating film comprises a layer comprising organic resin material.