Method for driving plasma display panel
A method for driving a plasma display panel (PDP) that can increase dark contrast without causing erroneous discharges is provided. A unit display period is divided into a plurality of subfields. A reset process and a sustain process are performed in one of the subfields. In the reset process, a reset pulse is applied to row electrodes of the PDP to initialize each discharge cell to an emission mode (or non-emission mode). In the sustain process, a sustain discharge is repeatedly generated a number of times, corresponding to the number of times a sustain pulse is to be applied, in those discharge cells that are in the emission mode. In this case, a peak potential of the reset pulse is changed based on the number of those discharge cells that are maintained in the non-emission mode during the unit display period and the number of times the sustain pulse is to be applied in the sustain process in this subfield.
1. A method for driving a plasma display panel based on pixel data of pixels derived from an image signal, the plasma display panel including a first substrate, a second substrate, a plurality of row electrode pairs provided on the first substrate and a plurality of column electrodes provided on the second substrate, discharge cells being formed respectively at intersections of the plurality of row electrode pairs with the plurality of column electrodes, and a unit display period of the image signal being divided into a plurality of subfields, said method comprising:
an addressing process for setting each said discharge cell to either an emission mode or a non-emission mode in each said subfield;
a sustain process for applying a sustain pulse in each said subfield;
a reset process for applying a reset pulse to one row electrode of two row electrodes in each said row electrode pair in one of said subfields of each said unit display period prior to the addressing process so as to initialize each of the discharge cells; and
an adjusting process for adjusting a peak potential of the reset pulse based on a number of those discharge cells that are maintained in the non-emission mode during the unit display period and on the number of times the sustain pulse is to be applied in the sustain process in said one of said subfields,
wherein the reset process includes a front half process for applying a first reset pulse to the one of two row electrodes in said row electrode pair and a rear half process subsequent to the front half process for applying a second reset pulse within the same one of said subfields to the one of two row electrodes in said row electrode pair, the second reset pulse being opposite in polarity to the first reset pulse, and
wherein a peak potential of the second reset pulse is adjusted based on the number of those discharge cells that are maintained in the non-emission mode during the unit display period and the number of times the sustain pulse is to be applied in the sustain process in said one of said subfields.
2. The method according to claim 1 , wherein, when the number of times the sustain pulse is to be applied in the sustain process of said one of said subfields is less than a predetermined number, an absolute value of the peak potential of the reset pulse is set to be smaller than when the number of times the sustain pulse is to be applied in the sustain process of said one of said subfields is equal to or greater than the predetermined number.
3. The method according to claim 1 , wherein, in the addressing process of said one of said subfields, each of the discharge cells is switched to the emission mode from the non-emission mode upon an addressing discharge that is selectively generated in the discharge cell based on the pixel data.
4. The method according to claim 1 , wherein the peak potential of the reset pulse is adjusted based on an accumulated running time of the plasma display panel.
5. The method according to claim 1 , wherein an absolute value of the peak potential of the reset pulse is reduced as the number of discharge cells that are maintained in the non-emission mode during the unit display period increases.