Display device driven with dual transistors

• US 6,859,195 B2
• Filed: 12/04/2001
• Issued: 02/22/2005
• Est. Priority Date: 12/14/2000
• Status: Active Grant

• Current Assignee: Chemtron Research LLC (Intellectual Ventures LLC)
• Original Assignee: International Business Machines Corporation
• Inventors: Kodate, Manabu
• Primary Examiner(s): Mancuso, Joseph
• Assistant Examiner(s): LeFlore, Laurel E
• Application Number:
  US09/683,226
• Publication Number:
  US 20020054003A1
• Time in Patent Office: 1,176 Days
• Field of Search: 345/92, 345/93, 349/46, 349/42, 349/48
• US Class Current: 345/92
• CPC Class Codes: G09G 2300/0814 used for selection purposes, e.g. logical AND for partial update
• CPC Class Codes: G09G 3/2011 by amplitude modulation
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G09G 3/3659 the addressing of the pixel involving the control of two or more scan electrodes or two or more data electrodes, e.g. pixel voltage dependant on signal of two data electrodes

Abstract

A display device including a display area having a plurality of pixels arranged in a matrix includes a plurality of scan lines for selecting pixel rows, a multiplex signal line for transmitting a display signal to at least two pixels in one pixel row selected by each of the scan lines, and a select line provided independently of the plurality of scan lines. The scan lines, the multiplex signal line and the select line are disposed in the display area. The select line selects at least one of a plurality of pixels in the pixel row to which the multiplex signal line transmits the display signal.

Claims

1. A display device including a plurality of pixels arranged in a matrix, comprising:

a plurality of scan lines for selecting pixel rows;

a multiplex signal line for transmitting a display signal to at least two pixels in one pixel row; and

a select line provided independently of said plurality of scan lines,

wherein one of the pixels in the pixel row to which said multiplex signal line transmits the display signal includes;

a pixel electrode;

a first switching device; and

a second switching device,

said second switching device is connected to said pixel electrode and said multiplex signal line,

said first switching device is connected to said scan line and said select line, and

said first switching device performs on-off control of said second switching device.

2. The display device according to claim 1,

wherein display signals are transmitted to every two pixels in each of said pixel rows by different multiplex signal lines,

one of the two pixels receiving the display signal from the same multiplex signal line is selected by said select line and the scan line of the pixel row including the pixel, and

the other pixel is selected only by said scan line.

3. The display device according to claim 1,

wherein said select line is disposed substantially parallel to said plurality of scan lines.

4. The display device according to claim 1, further comprising:

select lines provided independently of said plurality of scan lines, including;

a first select line; and

a second select line,

wherein said scan lines, said multiplex signal line and said select lines are disposed in said display area, and

wherein said first select line and said second select line transmit select signals with different timing,

said first select line and said second select line respectively select different pixels out of the pixels in the pixel row to which said multiplex signal line transmits the display signal.

5. The display device according to claim 1,

wherein the pixels in the pixel row to which said multiplex signal line transmit the display signal include:

a first pixel that is selected by said first select line; and

a second pixel that is selected by said second select line,

said first pixel maintains a display signal inputted when said first pixel is selected by said first select line and said scan line, and

said second pixel maintains a display signal inputted when said second pixel is selected by said second select line and said scan line.

6. The display device according to claim 5,

wherein display signals are transmitted to every two pixels in each of said pixel rows by different multiplex signal lines,

one of the two pixels receiving the display signal from the same multiplex signal line is selected by said first select line and the scan line of the pixel row including the pixel, and

the other pixel is selected by said second select line and said scan line.

7. The display device according to claim 5, further comprising a third select line for transmitting a select signal with different timing from the timing of said first and second select lines,

wherein display signals are transmitted to every three pixels in each of said pixel rows by different multiplex signal lines,

one of the three pixels receiving a display signal from the same multiplex signal line is selected by said first select line and the scan line of the pixel row including the pixel,

another one of said pixels is selected by said second select line and said scan line, and

the remaining pixel of said pixels is selected by said third select line and said scan line.

8. The display device according to claim 1,

wherein said select line and said multiplex signal line are disposed substantially parallel to each other and are alternately disposed between pixel electrodes, and

only one of said select line or said multiplex signal line is disposed between the pixel electrodes.

9. The display device according to claim 1,

wherein said multiplex signal line transmits a display signal to a first pixel and a second pixel in the same pixel row,

said first pixel includes:

said pixel electrode;

said first switching device; and

said second switching device,

said second switching device is connected to said pixel electrode and said multiplex signal line,

said first switching device is connected to said scan line and said select line,

said first switching device performs on-off control of said second switching device,

said second pixel includes;

a pixel electrode; and

a third switching device, and

said third switching device is connected to the pixel electrodes of said second pixel, said multiplex signal line and said scan line.

10. The display device according to claim 9,

wherein said first pixel maintains a display signal transmitted from said multiplex signal line when said second switching device is rendered to an on-state under the control of said first switching device, and

said second pixel maintains a display signal transmitted from said multiplex signal line when said second switching device is in an off-state and said third switching device is in an on-state.

11. The display device according to claim 1,

wherein said multiplex signal line and said pixel electrode are connected to a source/drain electrode of said second switching device, and

a source/drain electrode of said first switching device is connected to a gate electrode of said second switching device.

12. The display device according to claim 1, further comprising:

a first select line; and

a second select line,

wherein said first select line and said second select line transmit select signals with different timing,

said multiplex signal line transmits a display signal to the first pixel and the second pixel in the same pixel row,

said first pixel includes;

said pixel electrode,

said first switching device; and

said second switching device,

said second switching device is connected to the pixel electrode of said first pixel and said multiplex signal line,

said first switching device is connected to said scan line and said first select line,

said first switching device performs on-off control of said second switching device,

said second pixel includes;

said pixel electrode;

a third switching device; and

a fourth switching device,

said fourth switching device is connected to the pixel electrode of said second pixel and said multiplex signal line,

said third switching device is connected to said scan line and said second select line, and

said third switching device performs on-on control of said fourth switching device.

13. The display device according to claim 12,

wherein a gate electrode of said second switching device is connected to a source/drain electrode of said first switching device,

a source/drain electrode of said second switching device is respectively connected to the pixel electrode of said first pixel and said multiplex signal line,

a gate electrode of said fourth switching device is connected to a source/drain electrode of said third switching device, and

a source/drain electrode of said fourth switching device is respectively connected to the pixel electrode of said second pixel and said multiplex signal line.

14. The display device according to claim 12,

wherein said select lines and said multiplex signal lines are disposed substantially parallel to each other and are alternately disposed between the pixel electrodes, and only one of said select line or said multiplex signal line is disposed between the pixel electrodes.