DEVICES AND METHODS FOR REDUCING ARTEFACTS IN DISPLAY DEVICES BY THE USE OF OVERDRIVE

• US 20100207960A1
• Filed: 02/13/2009
• Published: 08/19/2010
• Est. Priority Date: 02/13/2009
• Status: Active Grant

• Current Assignee: Barco NV
• Original Assignee: Barco NV
• Inventors: Marchessoux, Cédric, Kimpe, Tom
• Granted Patent: US 9,280,943 B2
• Time in Patent Office: Days
• US Class Current: 345/618
• CPC Class Codes: G09G 2320/0247 Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes
• CPC Class Codes: G09G 2320/0252 Improving the response speed
• CPC Class Codes: G09G 2320/041 Temperature compensation
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 2340/16 Determination of a pixel data signal depending on the signal applied in the previous frame
• CPC Class Codes: G09G 2360/18 Use of a frame buffer in a display terminal, inclusive of the display panel
• CPC Class Codes: G09G 3/2044 using dithering
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

The invention relates to a method for reducing imaging artefacts during a frame-changeover from a current frame to a following frame displayed by a display device comprising a plurality of pixels, wherein the artefacts are reduced by overdriving at least one control signal for controlling the pixel intensity of the related pixel during the frame-changeover, wherein the overdrive is carried out in dependence of the magnitude of an intensity step between a designated start intensity value of the pixel within the current frame and a designated target intensity value of the pixel within the following frame.

Claims

1. Method for controlling imaging artefacts during a frame-changeover from a current frame to a following frame displayed by a display device comprising a plurality of pixels, wherein the artefacts are reduced by overdriving at least one control signal for controlling the pixel intensity of the related pixel during a frame-changeover, wherein the overdrive is carried out in dependence of a magnitude of an intensity step between a designated start intensity value of the pixel within the current frame and a designated target intensity value of the pixel within a or the following frame.

2. Method according to claim 1, wherein the magnitude of the overdrive depends on an intensity step between a designated start intensity value of the pixel within the current frame and a designated target intensity value of the pixel within a or the following frame

3. Method according to claim 1, wherein the method comprises the further step of determining an image noise characteristic from a set of frames, the set comprising at least the current frame and the or a following frame, wherein the overdriving is based upon the determined image noise characteristic.

4. Method according to claim 1, wherein the magnitude of the overdrive is based on a set of predetermined overdrive magnitudes.

5. Method according to claim 1, wherein the magnitude of the overdrive is based on the type of image content being displayed or the application for which the display system is being used.

6. Method according to claim 4, wherein the predetermined overdrive magnitudes are stored in a first memory.

7. Method according to claim 1, wherein the overdrive is carried out additionally in dependence of the magnitude of an intensity step between a currently reached intensity level of the pixel within the current frame and the target intensity value of the pixel within the or a following frame.

8. Method according to claim 1, wherein the magnitude of the overdrive is weighted by a predetermined overdrive weighting factor or predetermined overdrive weighting function, taking the human visual perception system into account.

9. Method according to claim 1, wherein the magnitude of the overdrive is adapted by a predetermined overdrive weighting factor or predetermined overdrive weighting function, such that the colour consistency of the display system is improved.

10. Method according to claim 1, wherein the magnitude of the overdrive for at least one type or colour of sub pixel is adjusted in accordance with a transition speed of at least one other type or colour of sub pixel.

11. Method according to claim 4, wherein the predetermined overdrive weighting factor or overdrive weighting function is stored in a second memory.

12. Method according to claim 1, wherein the display device is a liquid crystal display device.

13. Method according to claim 1, wherein the artefacts are reduced by overdriving each individual control signal for controlling the intensity of each related pixel during the frame-changeover.

14. A display device having means of reducing imaging artefacts during a frame-changeover from a current frame to a following frame displayed by a display device comprising a plurality of pixels, the display device comprising:

means for reducing the artefacts by overdriving at least one control signal for controlling the pixel intensity of the related pixel during a frame-changeover,

means for reducing the artefacts being adapted to carry out the overdrive in dependence of a magnitude of an intensity step between a designated start intensity value of the pixel within the current frame and a designated target intensity value of the pixel within a or the following frame.

15. The display device according to claim 14, further comprising means for determining an image noise characteristic from a set of frames, the set comprising at least the current frame and the or a following frame, wherein the overdriving is based upon the determined image noise characteristic.

16. The display device according to claim 14, wherein the means for reducing the artefacts determines the magnitude of the overdrive based on a set of predetermined overdrive magnitudes.

17. The display device according to claim 16, further comprising a first memory to store the set of predetermined overdrive magnitudes.

18. The display device according to claim 14, wherein the means for reducing the artefacts carries out the overdrive additionally in dependence of the magnitude of an intensity step between a currently reached intensity level of the pixel within the current frame and the target intensity value of the pixel within the or a following frame.

19. The display device according to claim 14, wherein the means for reducing the artefacts weights the magnitude of the overdrive by a predetermined overdrive weighting factor or predetermined overdrive weighting function, taking the human visual perception system into account.

20. The display device according to claim 19, wherein the predetermined overdrive weighting factor or overdrive weighting function is stored in a second memory.

21. The display device according to claim 14, wherein the display device is a liquid crystal display device.

22. The display device according to claim 14, wherein the artefacts are reduced by overdriving each individual control signal for controlling the intensity of each related pixel during the frame-changeover.

23. A controller for a display device having means of reducing imaging artefacts during a frame-changeover from a current frame to a following frame displayed by a display device comprising a plurality of pixels, the controller comprising:

means for reducing the artefacts by overdriving at least one control signal for controlling the pixel intensity of the related pixel during a frame-changeover,

means for reducing the artefacts being adapted to carry out the overdrive in dependence of a magnitude of an intensity step between a designated start intensity value of the pixel within the current frame and a designated target intensity value of the pixel within a or the following frame.

24. The controller according to claim 23, further comprising means for determining an image noise characteristic from a set of frames, the set comprising at least the current frame and the or a following frame, wherein the overdriving is based upon the determined image noise characteristic.

25. The controller according to claim 23, wherein the means for reducing the artefacts determines the magnitude of the overdrive based on a set of predetermined overdrive magnitudes.

26. The controller according to claim 25, further comprising a first memory to store the set of predetermined overdrive magnitudes.

27. The controller according to claim 23, wherein the means for reducing the artefacts carries out the overdrive additionally in dependence of the magnitude of an intensity step between a currently reached intensity level of the pixel within the current frame and the target intensity value of the pixel within the or a following frame.

28. The controller according to claim 23, wherein the means for reducing the artefacts weights the magnitude of the overdrive by a predetermined overdrive weighting factor or predetermined overdrive weighting function, taking the human visual perception system into account.

29. The controller according to claim 28, wherein the predetermined overdrive weighting factor or overdrive weighting function is stored in a second memory.

30. The controller according to claim 23, wherein the display device is a liquid crystal display device.

31. The controller according to claim 23, wherein controller is adapted to reduce the artefacts by overdriving each individual control signal for controlling the intensity of each related pixel during the frame-changeover.

32. A computer program product for controlling a display device having means of reducing imaging artefacts during a frame-changeover from a current frame to a following frame displayed by a display device comprising a plurality of pixels, the computer program product comprising code segments that are executable on a processing engine to provide:

means for reducing the artefacts by overdriving at least one control signal for controlling the pixel intensity of the related pixel during a frame-changeover,

means for reducing the artefacts being adapted to carry out the overdrive in dependence of a magnitude of an intensity step between a designated start intensity value of the pixel within the current frame and a designated target intensity value of the pixel within a or the following frame.

33. The computer program product according to claim 32, whose code segments further comprise, when executed on a processing engine:

means for determining an image noise characteristic from a set of frames, the set comprising at least the current frame and the or a following frame, wherein the overdriving is based upon the determined image noise characteristic.

34. The computer program product according to claim 32, wherein the means for reducing the artefacts determines the magnitude of the overdrive based on a set of predetermined overdrive magnitudes.

35. The computer program product according to claim 32, whose code segments, when executed on a processing engine, allow the means for reducing the artefacts to carry out the overdrive additionally in dependence of the magnitude of an intensity step between a currently reached intensity level of the pixel within the current frame and the target intensity value of the pixel within the or a following frame.

36. The computer program product according to claim 32, whose code segments, when executed on a processing engine, allow the means for reducing the artefacts to weight the magnitude of the overdrive by a predetermined overdrive weighting factor or predetermined overdrive weighting function, taking the human visual perception system into account.

37. A machine readable signal carrying medium storing the computer program product of claim 32.