Display apparatus with active matrix display panel, and method for driving same

• US 20070080906A1
• Filed: 09/29/2004
• Published: 04/12/2007
• Est. Priority Date: 10/02/2003
• Status: Abandoned Application

• Current Assignee: Pioneer Corporation
• Original Assignee: Pioneer Corporation
• Inventors: Tanabe, Takahisa
• Application Number:
  US10/574,100
• Publication Number:
  US 20070080906A1
• Time in Patent Office: Days
• US Class Current: 345/76
• CPC Class Codes: G09G 2300/0823 used to establish symmetry in driving, e.g. with polarity inversion
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2300/0852 being a dynamic memory with more than one capacitor
• CPC Class Codes: G09G 2310/0251 Precharge or discharge of pixel before applying new pixel voltage
• CPC Class Codes: G09G 2310/0254 Control of polarity reversal in general, other than for liquid crystal displays
• CPC Class Codes: G09G 2320/043 Preventing or counteracting the effects of ageing
• CPC Class Codes: G09G 3/2022 using sub-frames
• CPC Class Codes: G09G 3/3233 with pixel circuitry controlling the current through the light-emitting element

Abstract

A display apparatus with an active matrix display panel which can suppress gate stress to prevent a degradation of the display quality. Specified at least one pixel section having a light emitting element to driven for light emission in one row is supplied with a data pulse indicative of a first gate voltage of a thin film transistor upon supply of a display scanning pulse. Subsequently, each pixel in the one row is supplied with a reset scanning pulse, and when supplying a reset scanning pulse, the at least one pixel section is supplied with a reset pulse indicative of a second gate voltage of the thin film transistor for making the polarity of agate-to-source voltage or gate-to-drain voltage of the thin film transistor reverse to that during light emission driving.

Claims

1. A display apparatus with an active matrix display panel having a plurality of pixel sections each including a light emitting element and a thin film transistor, said display apparatus comprising:

a power supply for supplying a supply voltage to said plurality of pixel sections; and

display control means for sequentially specifying one of a plurality of rows of said display panel at a predetermined timing for each frame and at least one pixel section including a light emitting diode to be driven for light emission in the one row, supplying a display scanning pulse to each pixel section in the one row, supplying a data pulse indicative of a first gate voltage of said thin film transistor to the at least one pixel section when supplying the display scanning pulse, subsequently supplying a reset scanning pulse each of said pixel sections in the one row, and supplying a reset pulse to the at least one pixel section when supplying the reset scanning pulse, the reset pulse indicating a second gate voltage of said thin film transistor for making the polarity of a gate-to-source voltage or gate-to-drain voltage of said thin film transistor reverse to the polarity during light emission driving, wherein;

each of said plurality of pixel sections has a driving unit for supplying a gate of said thin film transistor with the first gate voltage corresponding to the data pulse in response to the display scanning pulse, and for supplying the gate of said thin film transistor with the second gate voltage corresponding to the reset pulse in response to the reset scanning pulse.

2. A display apparatus according to claim 1, wherein an absolute value of the gate-to-source voltage or gate-to-drain voltage of said thin film transistor depending on the first gate voltage is equal to an absolute value of the gate-to-source voltage or gate-to-drain voltage of said thin film transistor depending on the second gate voltage.

3. A display apparatus according to claim 1, wherein the gate-to-source voltage or gate-to-drain voltage of said thin film transistor depending on said second gate voltage is a fixed voltage.

4. A display apparatus according to claim 1, wherein each frame period has a display mode period in which the gate of said thin film transistor is supplied with the first gate voltage, and a reset mode period in which the gate of said thin film transistor is supplied with the second gate voltage.

5. A display apparatus according to claim 1, wherein a pixel section which is in a display mode period in which the gate of said thin film transistor is supplied with the first gate voltage in one frame period changes to a reset mode period in which the gate of said thin film transistor is supplied with said second gate voltage in the next frame period.

6. A display apparatus according to claim 5, wherein said pixel section comprises two equivalent driving circuits each have said thin film transistor, and said two driving circuits alternately switch the display mode and the reset mode.

7. A display apparatus according to claim 4, wherein the display mode period and said reset mode period are repeated based on a sub-field method in each frame period.

8. A display apparatus according to claim 1, wherein said light emitting element is an organic electroluminescence element.

9. A display apparatus according to claim 1, wherein said thin film transistor is an amorphous silicon thin film transistor.

10. A display apparatus according to claim 1, wherein said thin film transistor is an organic semiconductor thin film transistor.

11. A method for driving an active matrix display panel having a plurality of pixel sections each including a light emitting element and a thin film transistor, comprising the steps of:

supplying a supply voltage to said plurality of pixel sections; and

sequentially specifying one of a plurality of rows of said display panel at a predetermined timing for each frame and at least one pixel section including a light emitting diode to be driven for light emission in the one row, supplying a display scanning pulse to each pixel section in the one row, supplying a data pulse indicative of a first gate voltage of said thin film transistor to the at least one pixel section when supplying the display scanning pulse, subsequently supplying a reset scanning pulse each of said pixel sections in the one row, and supplying a reset pulse to the at least one pixel section when supplying the reset scanning pulse, the reset pulse indicating a second gate voltage of said thin film transistor for making the polarity of a gate-to-source voltage or gate-to-drain voltage of said thin film transistor reverse to the polarity during light emission driving, wherein;

in each of said plurality of pixel sections, a gate of said thin film transistor is supplied with the first gate voltage corresponding to the data pulse in response to the display scanning pulse, and the gate of said thin film transistor is supplied with the second gate voltage corresponding to the reset pulse in response to the reset scanning pulse.

12. A display method according to claim 11, wherein said light emitting element is an organic electroluminescence element.

13. A display method according to claim 11, wherein said thin film transistor is an amorphous silicon thin film transistor.

14. A display method according to claim 11, wherein said thin film transistor is an organic semiconductor thin film transistor.