Color passive matrix bistable liquid crystal display system and method for driving the same

• US 8,115,718 B2
• Filed: 05/24/2007
• Issued: 02/14/2012
• Est. Priority Date: 12/22/2006
• Status: Active Grant

• Current Assignee: Industrial Technology Research Institute
• Original Assignee: Industrial Technology Research Institute
• Inventors: Chen, Chih-Jen, Lu, Chih-Chiang, Chen, Tai-Ann, Chang, Chung-Yi
• Primary Examiner(s): Hjerpe, Richard
• Assistant Examiner(s): Harris, Dorothy
• Application Number:
  US11/802,699
• Publication Number:
  US 20080150868A1
• Time in Patent Office: 1,727 Days
• Field of Search: 345 94- 97
• US Class Current: 345/95
• CPC Class Codes: G09G 2300/0452 Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components
• CPC Class Codes: G09G 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 3/364 with use of subpixels
• CPC Class Codes: G09G 3/3681 suitable for passive matrices only

Abstract

This invention provides a color passive matrix bistable liquid crystal display system, in which one respective scan line corresponds to sub-pixels of same color and neighboring scan lines correspond to sub-pixels of different colors. The scan lines are grouped in accordance with the colors of the sub-pixels corresponding thereto such that different scan driving voltages can be provided to the sub-pixels of different colors when the scan lines are scanned. By way of the arrangement of the sub-pixels, different scan driving voltages are switched to the respective scan lines in accordance with the colors of the sub-pixels corresponding thereto. As a result, a demand that the sub-pixels of different colors require different scan driving voltages is satisfied. The image quality is improved.

Claims

1. A colorful passive matrix bistable liquid crystal display system, comprising:

a plurality of data electrodes aligned in parallel;

a plurality of scan electrodes aligned in parallel, wherein said scan electrodes are perpendicular to said data electrodes and both overlap each other, an intersection area of each said scan electrode and each said data electrode defines a sub-pixel, and each said scan electrode corresponds to a plurality of said sub-pixels of same color and said neighboring scan electrodes respectively correspond to said sub-pixels of different colors, said sub-pixels of different colors are constituted by red bistable liquid crystals, green bistable liquid crystals and blue bistable liquid crystals, wherein said red bistable liquid crystals, said green bistable liquid crystals and said blue bistable liquid crystals have the same cell size;

a pixel scan line driver electrically connecting with said scan electrodes and providing the same scan driving voltage to the sub-pixels of same color and different scan driving voltages to the sub-pixels of different color in accordance with the illuminating colors of said sub-pixels corresponding thereto, wherein the sub-pixels of red color have a lowest scan driving voltage and the sub-pixels of blue color have a largest scan driving voltage;

a data line driver electrically connecting with said data electrodes to provide data voltages to said data electrodes; and

a timing controller for controlling said pixel scan line driver and said data line driver to transmit the respective scan driving voltages and data voltages.

2. The colorful passive matrix bistable liquid crystal display system as claimed in claim 1, wherein further comprises a line buffer for storing and resorting sub-pixel data received by said timing controller such that said data line driver simultaneously transmits sub-pixel data of same color to said data electrodes corresponding to one said scan electrode.

3. The colorful passive matrix bistable liquid crystal display system as claimed in claim 2, wherein said data electrodes have different voltage levels corresponding to said sub-pixels of different illuminating colors.

4. The colorful passive matrix bistable liquid crystal display system as claimed in claim 2, wherein said data electrodes have same voltage level corresponding to said sub-pixels of different illuminating colors.

5. The colorful passive matrix bistable liquid crystal display system as claimed in claim 1, wherein said data electrodes have different voltage levels corresponding to said sub-pixels of different illuminating colors.

6. The colorful passive matrix bistable liquid crystal display system as claimed in claim 1, wherein said data electrodes have same voltage level corresponding to said sub-pixels of different illuminating colors.

7. A colorful passive matrix liquid crystal display system, which comprises sub-pixels of same color corresponding to one same scan line and sub-pixels of different colors corresponding to neighboring scan lines, wherein the same scan driving voltage is provided to the sub-pixels of same color and different scan driving voltages is provided to the sub-pixels of different color, wherein said sub-pixels of different colors are constituted by red bistable liquid crystals, green bistable liquid crystals and blue bistable liquid crystals, said red bistable liquid crystals, said green bistable liquid crystals and said blue bistable liquid crystals have the same cell size, wherein the sub-pixels of red color have a lowest scan driving voltage and the sub-pixels of blue color have a largest scan driving voltage.

8. The colorful passive matrix liquid crystal display system as claimed in claim 7, wherein said scan lines are grouped in accordance with the colors of said sub-pixels, and each group of said scan lines corresponds to different scan driving voltages.

9. The colorful passive matrix liquid crystal display system as claimed in claim 7, wherein further comprises a line buffer for storing and resorting sub-pixels data prior to scanning said scan lines so as to simultaneously transmit sub-pixel data of same color corresponding to one said scan line.

10. A method for driving passive matrix display medium, which provides the same scan driving voltage corresponding to the sub-pixels of same color and different scan driving voltages corresponding to sub-pixels of different illuminating colors, wherein said sub-pixels of different illuminating colors are constituted by red bistable liquid crystals, green bistable liquid crystals and blue bistable liquid crystals, said red bistable liquid crystals, said green bistable liquid crystals and said blue bistable liquid crystals have the same cell size, wherein the sub-pixels of red color have a lowest scan driving voltage and the sub-pixels of blue color have a largest scan driving voltage.

11. The method for driving passive matrix display medium as claimed in claim 10, which provides different voltage levels to data electrodes corresponding to said sub-pixels of different illuminating colors.

12. The method for driving passive matrix display medium as claimed in claim 10, which provides same voltage level to data electrodes corresponding to said sub-pixels of different illuminating colors.