METHOD FOR DRIVING DISPLAY DEVICE

• US 20110175894A1
• Filed: 01/13/2011
• Published: 07/21/2011
• Est. Priority Date: 01/20/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: NAKAMURA, Yasuo, WAKIMOTO, Kenichi
• Granted Patent: US 9,105,251 B2
• Time in Patent Office: Days
• US Class Current: 345/212
• CPC Class Codes: G02F 1/13306 Circuit arrangements or driving methods for the control of single liquid crystal cells G02F1/132, G02F1/133382 take precedence
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/134336 Matrix
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 2201/121 common or background
• CPC Class Codes: G02F 2201/123 pixel
• CPC Class Codes: G09G 2300/0426 Layout of electrodes and connections
• CPC Class Codes: G09G 2310/0237 Switching ON and OFF the backlight within one frame
• CPC Class Codes: G09G 2310/08 Details of timing specific for flat panels, other than clock recovery
• CPC Class Codes: G09G 2320/0214 with crosstalk due to leakage current of pixel switch in active matrix panels
• CPC Class Codes: G09G 2320/0261 in the context of movement of objects on the screen or movement of the observer relative to the screen
• CPC Class Codes: G09G 2320/103 Detection of image changes, e.g. determination of an index representative of the image change
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2330/026 Arrangements or methods related to booting a display
• CPC Class Codes: G09G 3/3413 Details of control of colour illumination sources
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

An object is to provide a convenient display device which consumes sufficiently small amount of power and a method for driving such a display device. The display device can be in an off state with a still image displayed in a still image display mode in which a pixel electrode and a common electrode which are for applying a voltage to the display element are brought into a floating state so that a voltage applied to the display element is held, and a still image is displayed without further supply of a potential. The display device is put to an off state with a desired image displayed in the still image display mode, whereby the display device can have a higher level of security and can be more convenient.

Claims

1. A method for driving a display device, comprising:

displaying an image on a screen by supplying a power supply potential from a power source;

writing an initialization image signal to the display device;

displaying an initialization image on the screen; and

stopping supply of the power supply potential with the initialization image displayed on the screen.

2. The method for driving a display device, according to claim 1, wherein supplying the power supply potential is controlled by a transistor comprising an oxide semiconductor.

3. The method for driving a display device, according to claim 1, wherein a period of time in which the initialization image is displayed after supply of the power supply potential is stopped is set by controlling a period of time in which a light source is driven.

4. A method for driving a display device, comprising:

displaying an image on a screen by supplying a power supply potential from a power source;

supplying a retention and stop signal to the display device; and

stopping supply of the power supply potential with the image displayed on the screen.

5. The method for driving a display device, according to claim 4, wherein supplying the power supply potential is controlled by a transistor comprising an oxide semiconductor.

6. The method for driving a display device, according to claim 4, wherein a period of time in which the image is displayed after supply of the power supply potential is stopped is set by controlling a period of time in which a light source is driven.

7. The method for driving a display device, according to claim 4, wherein supply of the power supply potential is stopped after writing an image signal of one frame is finished.

8. A method for driving a display device, comprising:

displaying an image on a screen by supplying a power supply potential from a power source and applying a voltage to a display element;

writing an initialization image signal to the display device;

displaying an initialization image on the screen; and

stopping supply of the power supply potential while the initialization image is displayed on the screen by application of the voltage to the display element.

9. The method for driving a display device, according to claim 8, wherein supplying the power supply potential is controlled by a transistor comprising an oxide semiconductor.

10. The method for driving a display device, according to claim 8, wherein a period of time in which the initialization image is displayed after supply of the power supply potential is stopped is set by controlling a period of time in which a light source is driven.

11. A method for driving a display device, comprising:

displaying an image on a screen by supplying a power supply potential from a power source and applying a voltage to a display element;

supplying a retention and stop signal to the display device; and

stopping supply of the power supply potential while the image is displayed on the screen by application of the voltage to the display element.

12. The method for driving a display device, according to claim 11, wherein supplying the power supply potential is controlled by a transistor comprising an oxide semiconductor.

13. The method for driving a display device, according to claim 11, wherein a period of time in which the image is displayed after supply of the power supply potential is stopped is set by controlling a period of time in which a light source is driven.

14. The method for driving a display device, according to claim 11, wherein supply of the power supply potential is stopped after writing an image signal of one frame is finished.

15. A method for driving a display device, comprising:

displaying an image on a screen by supplying a power supply potential from a power source through a transistor and applying a voltage to a display element;

writing an initialization image signal to the display device;

displaying an initialization image on the screen; and

turning off the transistor to bring the display element into a floating state while the initialization image is displayed on the screen by holding of the voltage applied to the display element.

16. The method for driving a display device, according to claim 15, wherein the transistor comprises an oxide semiconductor.

17. The method for driving a display device, according to claim 15, wherein a period of time in which the initialization image is displayed after the transistor is turned off is set by controlling a period of time in which a light source is driven.

18. A method for driving a display device, comprising:

displaying an image on a screen by supplying a power supply potential from a power source through a transistor and applying a voltage to a display element;

supplying a retention and stop signal to the display device; and

turning off the transistor to bring the display element into a floating state while the image is displayed on the screen by holding of the voltage applied to the display element.

19. The method for driving a display device, according to claim 18, wherein the transistor comprises an oxide semiconductor.

20. The method for driving a display device, according to claim 18, wherein a period of time in which the image is displayed after the transistor is turned off is set by controlling a period of time in which a light source is driven.

21. The method for driving a display device, according to claim 18, wherein supply of the power supply potential is stopped after writing an image signal of one frame is finished.