Reduction of phosphor lag artifacts on display panels
View Patent ↗Since the phosphor lag effect results from the slowness of the green and red phosphors and since it is not possible to make these phosphors faster, the blue one has to be made slower in order to reduce the color trail effect. Therefore, a part of the blue component is artificially delayed. Only a certain percentage of the blue component of the actual frame is transmitted during the actual frame, whereas the rest of the blue component will be transmitted during the next frames. The dynamic false contour effect introduced by this video processing may be compensated by subfield shifting.
1. Method for processing video pictures for display on a display device having at least a first kind of luminous elements with a first time response and a second kind of luminous elements with a second time response being slower than the first time response by
driving a luminous element of said first kind for one frame with a predetermined energy, and
driving said luminous element of said first kind in one frame with a first part of said predetermined energy and in a following frame with a second part of said predetermined energy.
2. Method according to claim 1 , wherein the sum of the first and second part corresponds to the total predetermined energy.
3. Method according to claim 1 , wherein said luminous element of the second kind is driven in said one frame with the same amount of predetermined energy, so that the same energy is emitted from said luminous elements of said first and second kind in said one frame.
4. Method according to claim 1 , wherein the display device further includes a third kind of luminous elements with a third time response being slower than the second time response.
5. Method according to claim 4 , wherein the first kind of luminous elements includes blue phosphor elements, the second kind red phosphor elements and the third kind green phosphor elements.
6. Method according to claim 1 , wherein the display device includes a plasma display panel.
7. Method according to claim 1 , wherein a factor between the first and second part of said predetennined energy is determined in advance and used for calculating a driving energy for each luminous element of said first kind.
8. Method according to claim 1 , including the step of storing in a frame memory for all luminous elements of said first kind of one frame at least second parts of predetermined energies for displaying in a later frame.
9. Device for processing video pictures for display on a display device having at least a first kind of luminous elements with a first time response and a second kind of luminous elements with a second time response being slower than the first time response and driving means for driving a luminous element of said first kind for one frame with a predetermined energy, wherein said driving means enables driving said luminous element of said first kind in one frame with a first part of said predetermined energy and in a following frame with a second part of said predetermined energy.
10. Device according to claim 9 , wherein the sum of the first and second parts of the predetermined energy corresponds to the total predetermined energy.
11. Device according to claim 9 , including controlling means for driving said luminous element of said second kind in said one frame period with the same amount of said predetermined energy, so that the same energy is emitted from said luminous elements of said first and second kinds in said one frame.
12. Device according to claim 9 , wherein said display device further includes luminous elements of a third kind with a third time response being slower than said second time response.
13. Device according to claim 12 , wherein said first kind of luminous elements includes blue phosphor elements, said second kind includes red phosphor elements and said third kind includes green phosphor elements.
14. Device according to claim 9 , wherein said display device includes a plasma display panel.
15. Device according to claim 9 , further including a frame memory for storing for all luminous elements of said first kind of one frame at least second parts of predetermined energies for displaying in a later frame.