Switchable display devices

• US 6,417,868 B1
• Filed: 09/02/1999
• Issued: 07/09/2002
• Est. Priority Date: 09/03/1998
• 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: Katsuse, Hirofumi, Cairns, Graham Andrew, Bock, Harald Reinhart
• Primary Examiner(s): Razavi, Michael
• Assistant Examiner(s): CUNNINGHAM, GREGORY F
• Application Number:
  US09/389,132
• Time in Patent Office: 1,041 Days
• Field of Search: 345/84, 345/87-89, 345/103, 345/690, 345/694, 345/695, 345/696, 345/698
• US Class Current: 345/698
• CPC Class Codes: G09G 2310/0205 Simultaneous scanning of several lines in flat panels
• CPC Class Codes: G09G 2310/0297 Special arrangements with multiplexing or demultiplexing of display data in the drivers for data electrodes, in a pre-processing circuitry delivering display data to said drivers or in the matrix panel, e.g. multiplexing plural data signals to one D/A converter or demultiplexing the D/A converter output to multiple columns
• CPC Class Codes: G09G 2340/0407 Resolution change, inclusive of the use of different resolutions for different screen areas
• CPC Class Codes: G09G 2340/0428 Gradation resolution change
• CPC Class Codes: G09G 3/2074 using sub-pixels
• CPC Class Codes: G09G 3/3607 for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127
• CPC Class Codes: G09G 3/364 with use of subpixels
• CPC Class Codes: G09G 3/3674 Details of drivers for scan electrodes
• CPC Class Codes: G09G 3/3685 Details of drivers for data electrodes

Abstract

A display device comprising a plurality of picture elements arranged in rows and columns, each picture element being switchable between at least two states having different optical output characteristics, a plurality of row and column drivers, connected to said rows and columns respectively, for switching said picture elements between said states, wherein at least one switch is provided for switching at least one of said drivers between a first configuration in which the driver drives at least one row or column, and a second configuration, different from said first configuration, in which the driver drives at least two rows or columns.

Claims

1. A display device comprising a plurality of picture elements arranged in rows and columns, and a plurality of row and column drivers, connected to said rows and columns respectively, for driving said picture elements, wherein at least one switch is provided for switching at least one of said drivers between a first configuration in which at least a first driver drives a first row or column, and at least a second driver drives at least a second and a third row or column, and a second configuration, different from said first configuration, in which the at least first driver drives at least the first and third row or column, and the at least second driver drives the second row or column.

2. A display device as claimed in claim 1, wherein said at least one switch is a row switch which switches at least one of said row drivers between said first and second configurations, and wherein the display device also comprises at least one column switch for switching at least one of said column drivers between a third configuration in which the column driver drives at least one column, and a fourth configuration, different from said third configuration, in which the column driver drives at least two columns.

3. A display device as claimed in claim 1, wherein each picture element is switchable between only two states, said two states having different optical characteristics from each other.

4. A display device as claimed in claim 3, wherein said two states correspond to the picture element being on and off.

5. A display device as claimed in claim 1, wherein at least one picture element emits or transmits light at a different wavelength to other picture elements.

6. A display device as claimed in claim 1 wherein at least one of said picture elements emits or transmits red light, at least one of said picture elements emits or transmits green light, and at least one of said picture elements emits or transmits blue light.

7. A display device as claimed in claim 1 wherein operation of said switch or switches allows the display device to operate in at least two resolutions, including a high resolution mode and a low resolution mode.

8. A display device as claimed in claim 7, wherein the number of grey levels in the low resolution mode is higher than would be possible without said switch or switches, for a device also capable of operating in said high resolution mode.

9. A display device as claimed in claim 1, wherein said plurality of picture elements are arranged in an array of identical groups of picture elements, each group being formed by picture elements at the intersection of number of adjacent rows and columns of picture elements, and each group containing picture elements of different sizes.

10. A display device as claimed in claim 9, wherein each group of picture elements is connected to an identical switch or set of switches.

11. A display device as claimed in claim 1, which is formed from a liquid crystal panel.

12. A display device as claimed in claim 11, wherein said liquid crystal panel forms a passively addressed array.

13. A display device as claimed in claim 1, wherein said display device is a bistable mode liquid crystal display.

14. A display device as claimed in claim 1, wherein said display device is a bistable twisted nematic liquid crystal display.

15. A display device as claimed in claim 1 wherein said plurality of picture elements are arranged in an array of 9 picture elements which form three columns and three rows of picture elements, the sizes of the respective picture elements in the three columns having a ratio of 2:

1;

3, and the sizes of the respective picture elements in the three rows having a ratio 1.5;

1;

2.5.

16. A display device as claimed in claim 15, wherein the three columns are addressed by three column electrodes, respectively, and the three rows are addressed by three row electrodes respectively.

17. A display device as claimed in claim 1 wherein said plurality of picture elements are arranged in an array of 27 picture elements which form three rows and nine columns of picture elements, the sizes of the respective picture elements in the three rows having a ratio of 1.5:

1;

2.5, the nine columns of picture elements forming a first set of six column elements and a second set of three column elements, the sizes of the respective first and second sets having a ratio of 1;

1, the sizes of the respective column elements of the first set having a ratio of 2;

1;

2;

1;

2;

1, the sizes of the respective column elements of the second set having a ratio of 3;

3;

3, and further wherein a first set of color filters forming red, green and blue filters are placed over the first set of six column elements and a second set of color filters forming red, green and blue filters are placed over the second set of three column elements, the color filters being equally sized in a row direction and covering the array in six sequentially-aligned vertical stripes in perpendicular relation to the rows of picture elements.

18. A display device as claimed in claim 7, wherein said display device forms an actively addressed array.

19. A display device as claimed in claim 18, wherein each pixel element has at most 8 greylevels in the highest resolution mode.

20. A display device as claimed in claim 2, wherein each picture element is switchable between only two states.

21. A display device as claimed in claim 2, wherein at least one of the picture elements emits or transmits light at a different wavelength to other picture elements.

22. A display device as claimed in claim 2, wherein at least one of said picture elements emits or transmits red light, at least one of said picture elements emits or transmits green light, and at least one of said picture elements emits or transmits blue light.

23. A display device as claimed in claim 2, wherein operation of said switch or switches allows the display device to operate in at least two resolutions, including a high resolution mode and a low resolution mode.

24. A display device as claimed in claim 2, wherein said plurality of picture elements are arranged in an array of identical groups of picture elements, each group being formed by picture elements at the intersection of number of adjacent rows and columns of picture elements, and each group containing picture elements of different sizes.

25. A display device as claimed in claim 2, which is formed from a liquid crystal panel.

26. A display device as claimed in claim 2, wherein said display device is a bistable liquid crystal mode.

27. A display device as claimed in claim 2, wherein said display device is a bistable twisted nematic liquid crystal display.

28. A display device as claimed in claim 2, wherein said plurality of picture elements are arranged in an array of 9 picture elements which form three columns and three rows of picture elements, the sizes of the respective picture elements in the three columns having a ratio of 2:

1;

3, and the sizes of the respective picture elements in the three rows having a ratio 1.5;

1;

2.5.

29. A display device as claimed in claim 2, wherein said plurality of picture elements are arranged in an array of 27 picture elements which form three rows and nine columns of picture elements, the sizes of the respective picture elements in the three rows having a ratio of 1.5:

1;

2.5, the nine columns of picture elements forming a first set of six column elements and a second set of three column elements, the sizes of the respective first and second sets having a ratio of 1;

1, the sizes of the respective column elements of the first set having a ratio of 2;

1;

2;

1;

2;

1, the sizes of the respective column elements of the second set having a ratio of 3;

3;

3, and further wherein a first set of color filters forming red, green and blue filters are placed over the first set of six column elements and a second set of color filters forming red, green and blue filters are placed over the second set of three column elements, the color filters being equally sized in a row direction and covering the array in six sequentially-aligned vertical stripes in perpendicular relation to the rows of picture elements.