Liquid crystal display

• US 8,416,374 B2
• Filed: 02/12/2007
• Issued: 04/09/2013
• Est. Priority Date: 12/11/2001
• Status: Expired due to Fees

• Current Assignee: Japan Display West Incorporated (Japan Display Incorporated)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Ino, Masumitsu
• Primary Examiner(s): CHEN, WEN YING PATTY
• Application Number:
  US11/705,366
• Publication Number:
  US 20070146593A1
• Time in Patent Office: 2,248 Days
• Field of Search: None
• US Class Current: 349/114
• CPC Class Codes: G02F 1/133371 Cells with varying thickness of the liquid crystal layer
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 2203/02 reflective

Abstract

A liquid crystal display able to deal with high definition display and able to secure both of a transmission type display luminance and a reflection type display luminance, wherein light from backlights 71a and 71b are focused by a lens sheet 74, luminance of the backlights is improved, a transmittance can be set at 4 percent to 10 percent, a reflectance can be set in a range from 1 percent to 25 percent, and high definition display is handled while securing a display light luminance equivalent to that of a liquid crystal display performing only transmission type display and a reflection display light luminance required for the display without increasing a power consumption of the backlights.

Claims

1. A liquid crystal display having a pixel region with a plurality of pixels capable of displaying an image including a plurality of reflection portions for display by ambient light introduced from the outside and a plurality of transmission portions for display by light from an internal light source, wherein a reflectance of the light by the reflection portion of a selected pixel is 1 percent to 30 percent of the light incident thereon, for defining an entire display signal range from a lowest value to highest value and a transmittance of light by the transmission portion of a selected pixel is at most from 5 percent to 10 percent of the light incident thereon, for defining an entire display signal range from a lowest value to highest value, and further wherein the reflection electrode is formed exclusively in an interconnect region such that it is substantially centered over a conductor extending along the side of the pixel at which the reflection electrode is located and the reflection electrode has a center line average roughness of less than or equal to 0.02 micrometers and further wherein the reflection region is exclusively located above a Cs line interconnect region with an opening in the color filter being centered directly over the Cs line interconnect while maintaining the specified reflectance and transmittance characteristics.

2. A liquid crystal display as set forth in claim 1, wherein each of said reflection portions has a function of scattering the incident light.

3. A liquid crystal display as set forth in claim 1, wherein each of said reflection portions has a function of selectively reflecting the incident light.

4. A liquid crystal display as set forth in claim 1, wherein each of said reflection portions is comprised of a metal film having a high reflectance.

5. A liquid crystal display as set forth in claim 1, wherein a color filter is provided only at said transmission portions.

6. A liquid crystal display as set forth in claim 5, wherein the color filter is formed at a location corresponding to each pixel, and an opening is formed in said color filter at each of said reflection portions.

7. A liquid crystal display as set forth in claim 6, wherein said opening is formed at an approximate center of each of said reflection portions.

8. A liquid crystal display as set forth in claim 1, wherein, in said display panel, under conditions of irradiation of the light of said light source of 500 cd/m.sup.2 to 25000 cd/m.sup.2, the amount of the display light is 20 cd/m.sup.2 to 200 cd/m.sup.2.

9. A liquid crystal display as set forth in claim 1, wherein, in said display panel, under conditions of irradiation of the light of said ambient light of 2000 lx to 50000 lx, the amount of the display light is 200 cd/m.sup.2 to 1000 cd/m.sup.2.

10. A liquid crystal display as set forth in claim 1, wherein, in said pixel region, an area of said transmission portion is at least 40 percent of each pixel, and the area of said reflection portion is 1 percent to 60 percent of the overall pixel.

11. A liquid crystal display as set forth in claim 1, wherein, in said pixel region, an aperture ratio of said transmission portion is 40 percent to 100 percent of each pixel.

12. A liquid crystal display having a pixel region comprised of a plurality of individually addressable pixels, each pixel in the pixel region having a reflection region for display by ambient light introduced from the outside and a transmission region for display by light from an internal light source, wherein a reflectance of the light by the reflection region of a selected pixel is 1 percent to 30 percent of the light incident thereon, for defining an entire display signal range from a lowest value to highest value, and a transmittance of the light by the transmission region of a selected pixel is at most 5 percent to 10 percent of the light incident thereon for defining an entire display signal range from a lowest value to highest value, and further wherein the reflection electrode is formed exclusively in an interconnect region such that it is substantially centered over a conductor extending along the side of the pixel at which the reflection electrode is located and the reflection electrode has a center line average roughness of less than or equal to 0.02 micrometers and further wherein the reflection region is exclusively located above a Cs line interconnect region with an opening in the color filter being centered directly over the Cs line interconnect while maintaining the specified reflectance and transmittance characteristics.

13. A liquid crystal display as set forth in claim 12, wherein each of said reflection regions has a function of scattering the incident light.

14. A liquid crystal display as set forth in claim 12, wherein each of said reflection regions has a function of regularly reflecting the incident light.

15. A liquid crystal display as set forth in claim 12, wherein each of said reflection regions is formed by a metal film having a high reflectance.

16. A liquid crystal display as set forth in claim 12, wherein a color filter is provided in only said transmission regions.

17. A liquid crystal display as set forth in claim 16, wherein the color filter is formed at a location corresponding to said pixel region, and an opening is formed in said color filter in each of said reflection regions.

18. A liquid crystal display as set forth in claim 17, wherein said opening is formed at an approximate center of each of said reflection regions.

19. A liquid crystal display as set forth in claim 12, wherein, in said display panel, under conditions of irradiation of the light of said light source of 500 cd/m.sup.2 to 25000 cd/m.sup.2, the amount of the display light is 20 cd/m.sup.2 to 200 cd/m.sup.2.

20. A liquid crystal display as set forth in claim 12, wherein, in said display panel, under conditions of irradiation of the light of said ambient light of 2000 lx to 50000 lx, the amount of the display light is 200 cd/m.sup.2 to 1000 cd/m.sup.2.

21. A liquid crystal display as set forth in claim 12, wherein, in said pixel region, an area of said transmission region is at least 40 percent of the overall pixel region, and the area of said reflection region is 1 percent to 60 percent of the overall pixel region.

22. A liquid crystal display as set forth in claim 12, wherein, in said pixel region, an aperture ratio of said transmission region is 40 percent to 100 percent of the overall pixel region.