Method for driving plasma display panel
A method for driving a plasma display panel is provided in which a wall voltage at an interelectrode between a display electrode and an address electrode is controlled without increasing contrast in preparation for addressing, so that reliability of addressing is improved. As an operation of initialization for controlling the wall voltage of a cell within a screen as a preparation for the addressing, a first blunt wave application is performed for generating discharge only in a previous non-lighted cell that was not lighted in a previous display, and a second blunt wave application is performed for generating discharge in each of the previous non-lighted cell and a previous lighted cell that was lighted in the previous display.
1. A method for driving a three-electrode surface discharge AC type plasma display panel that has a screen in which first display electrodes, second display electrodes and address electrodes are arranged, the method comprising:
repeating initialization for equalizing wall voltages in all cells that constitute the screen, addressing for setting the wall voltage of each cell to a value corresponding to relevant display data in accordance with display data, and sustaining for generating display discharge a predetermined number of times only in cells to be lighted;
applying a blunt wave at least two times as the initialization operation so that a potential of at least one electrode of all the cells increases or decreases simply;
generating discharge only in a previous non-lighted cell that was not lighted in the last sustaining process that was performed before the initialization so that the wall voltage thereof approaches a wall voltage of a previous lighted cell that was lighted in the last sustaining process, in the first blunt wave application among the at least two blunt wave applications; and
generating discharge in the previous lighted cell and the previous non-lighted cell so that the wall voltage of these cells change to set values, in the second blunt wave application.
2. The method according to claim 1 , further comprising selecting cells by the second display electrode and the address electrode in the addressing; and
generating discharge between display electrodes in which the second display electrode becomes a cathode and generating discharge between the second display electrode and the address electrode in the previous lighted cell and the previous non-lighted cell, in the second blunt wave application in the initialization.
3. The method according to claim 1 , wherein the final display discharge in the sustaining process is made discharge in which the second display electrode is an anode, and the second blunt wave application in the initialization is performed so as to satisfy the following inequality,
2 Vt AY −Vt XY ≦2 V AY −V XY −2 Va off ,
where Vt AY represents a discharge start threshold level voltage when discharge in which the second display electrode becomes a cathode is generated between the second display electrode and the address electrode, Vt XY represents a discharge start threshold level voltage when discharge in which the second display electrode becomes a cathode is generated between the first display electrode and the second display electrode, V AY represents a final voltage between the second display electrode and the address electrode in the blunt wave application, V XY represents a final voltage between the first display electrode and the second display electrode in the blunt wave application, and Va off represents a dc component of an alternating pulse that is a difference between a potential of the address electrode and a potential of the second display electrode when display discharge is generated in the sustaining process.
4. The method according to claim 1 , wherein adding to the two blunt wave applications as the initialization operation, a rectangular waveform is applied so as to increase or decrease a potential of at least one electrode of all the cells so that pulse discharge is generated,
the rectangular waveform application is performed before the first blunt wave application, and in the rectangular waveform application, discharge is generated only in the previous lighted cell so that the wall voltage thereof approaches a wall voltage of a previous lighted cell that was lighted in the final sustaining process.
5. The method according to claim 4 , wherein the last display discharge in the sustaining process is made discharge in which the first display electrode becomes an anode.
6. The method according to claim 4 , wherein the rectangular waveform application and the first blunt wave application are performed continuously so that an electrode potential does not change between them.