DISPLAY DEVICE AND METHOD OF DRIVING THE SAME

• US 20080068359A1
• Filed: 09/06/2007
• Published: 03/20/2008
• Est. Priority Date: 09/15/2006
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: KIMURA, Hajime, YOSHIDA, Yasunori
• Granted Patent: US 8,878,757 B2
• Time in Patent Office: Days
• US Class Current: 345/204
• CPC Class Codes: G09G 2300/0819 used for counteracting undesired variations, e.g. feedback or autozeroing
• 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 2300/0861 with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes
• CPC Class Codes: G09G 2310/024 Scrolling of light from the illumination source over the display in combination with the scanning of the display screen
• CPC Class Codes: G09G 2310/061 for resetting or blanking
• CPC Class Codes: G09G 2310/08 Details of timing specific for flat panels, other than clock recovery
• CPC Class Codes: G09G 2320/02 Improving the quality of display appearance
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/0252 Improving the response speed
• 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 2320/0271 Adjustment of the gradation levels within the range of the gradation scale, e.g. by redistribution or clipping
• CPC Class Codes: G09G 2320/0276 for the purpose of adaptation to the characteristics of a display device, i.e. gamma correction
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2320/0673 for control of gamma adjustment, e.g. selecting another gamma curve
• CPC Class Codes: G09G 2320/10 Special adaptations of display systems for operation with variable images
• CPC Class Codes: G09G 2320/106 Determination of movement vectors or equivalent parameters within the image
• CPC Class Codes: G09G 2340/0435 Change or adaptation of the frame rate of the video stream
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 2360/18 : Use of a frame buffer in a display terminal, inclusive of the display panel
• CPC Class Codes: G09G 3/2025 : the sub-frames having all the same time duration
• CPC Class Codes: G09G 3/3233 : with pixel circuitry controlling the current through the light-emitting element
• CPC Class Codes: G09G 3/325 : the data current flowing through the driving transistor during a setting phase, e.g. by using a switch for connecting the driving transistor to the data driver
• CPC Class Codes: G09G 3/3258 : with pixel circuitry controlling the voltage across the light-emitting element
• CPC Class Codes: G09G 3/3406 : Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/36 : using liquid crystals
• CPC Class Codes: G09G 3/3648 : using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: H01L 27/1214 : comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/124 : with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1255 : integrated with passive devices, e.g. auxiliary capacitors
• CPC Class Codes: H01L 29/42384 : for thin film field effect transistors, e.g. characterised by the thickness or the shape of the insulator or the dimensions, the shape or the lay-out of the conductor

Abstract

The present invention solves the motion blur of moving images in hold-type display devices. An amount of a moving image is detected from image data included in frames and an image at the intermediate state between an image of the current frame and an image of the next frame is made as an interpolation image. Thus, the movement of the image can follow the movement of human eyes and the luminance of the interpolation image is changed, and thus, display can be made close to pseudo impulse type display. In this manner, hold-type display devices without motion blur and methods of driving the hold-type display devices can be provided.

Claims

1. A method of driving a liquid crystal display device having a display screen, comprising the steps of:

displaying first to third images sequentially on the display screen;

wherein;

the first image and the third image are each formed by an external video signal;

the second image is formed based on the external video signal for the first image and the external video signal for the third image; and

the luminance of the second image is lower than the luminance of the first image.

2. A method of driving a liquid crystal display device having a display screen, comprising the steps of:

displaying first to third images sequentially on the display screen;

wherein;

the first image and the third image are each formed by an external video signal;

the second image is an image at the intermediate state between the first image and the third image; and

the luminance of the second image is lower than the luminance of the first image.

3. A method of driving a liquid crystal display device having a display screen, comprising the steps of:

displaying first to third images sequentially on the display screen;

wherein;

the first image and the third image are each formed by an external video signal;

the second image is a compensation image formed from the first image and the third image; and

the luminance of the second image is lower than the luminance of the first image.

4. A method of driving a liquid crystal display device having a display screen, comprising the steps of:

displaying first to third images sequentially on the display screen;

wherein;

the first image and the third image are each formed by an external video signal;

the second image is an image formed by motion compensation from the first image and the third image; and

the luminance of the second image is lower than the luminance of the first image.

5. A display device comprising:

a display screen, the display screen sequentially displaying first to third images; and

a control circuit, the control circuit comprising;

means for forming the first image and the third image by external video signals;

means for forming the second image based on the external video signal for the first image and the external video signal for the third image; and

means for lowering the luminance of the second image than the luminance of the first image.

9. An electronic device comprising the liquid crystal display device according to claim 5.

6. A display device comprising:

a display screen, the display screen sequentially displaying first to third images; and

a control circuit, the control circuit comprising;

means for forming the first image and the third image by external video signals;

means for forming the second image to be at the intermediate state between the first image and the third image; and

means for lowering the luminance of the second image than the luminance of the first image.

10. An electronic device comprising the liquid crystal display device according to claim 6.

7. A display device comprising:

a display screen, the display screen sequentially displaying first to third images; and

a control circuit, the control circuit comprising;

means for forming the first image and the third image by external video signals;

means for forming the second image as a compensation image formed from the first image and the third image; and

means for lowering the luminance of the second image than the luminance of the first image.

11. An electronic device comprising the liquid crystal display device according to claim 7.

8. A display device comprising:

a display screen, the display screen sequentially displaying first to third images; and

a control circuit, the control circuit comprising;

means for forming the first image and the third image by external video signals;

means for forming the second image by motion compensation from the first image and the third image; and

means for lowering the luminance of the second image than the luminance of the first image.

12. An electronic device comprising the liquid crystal display device according to claim 8.