Method of driving a plasma display panel
View Patent ↗A plasma display panel (PDP), and a method of driving plasma display panel, achieve improved contrast by minimizing quantity of luminescence in a non-luminescent display period, that is, a reset period. A method of driving a PDP having a plurality of discharge cells with a plurality of scanning electrodes, a plurality of sustain electrodes, and a plurality of address electrodes involves forming a frame having a plurality of sub-fields; causing a reset discharge in only first sub-fields of the respective plurality of discharge cells; deciding ON/OFF state of discharge cells in current sub-field in accordance with ON/OFF state of discharge cells in previous sub-field; and converting the discharge cell into any one of ON/OFF wall electric charges in accordance with the ON/OFF state of the decided discharge cell.
1. A method of driving a plasma display panel comprising a plurality of discharge cells including a plurality of scanning electrodes, a plurality of sustain electrodes, and a plurality of address electrodes, comprising:
a step of forming a frame having a plurality of sub-fields;
a step of applying a reset pulse to scanning electrode in only first sub-fields, to form wall electric charge in the discharge cells using a lamp waveform to increase voltage in Set-up of the reset pulse, and to partially eliminate unnecessary charged particles using a lamp waveform to decrease voltage in Set-down of the reset pulse while applying a positive DC voltage to the sustain electrode.
2. The method according to claim 1 , wherein, in the frame including the plurality of sub-fields, the first sub-field is divided into a reset period, an address period, and a sustain period, and the other sub-fields are divided into address period and sustain period.
3. The method according to claim 1 , further comprising:
a step of deciding ON/OFF state of discharge cells in current sub-field in accordance with ON/OFF state of discharge cells in previous sub-field; and
a step of converting the discharge cell into any one of ON/OFF wall electric charges in accordance with ON/OFF state of the decided discharge cell.
4. The method according to claim 3 , wherein a step of converting an ON state discharge cell in the previous sub-field into an OFF state wall electric charge in address period of the current sub-field comprises
a step of applying a scan pulse to the scanning electrode in the address period;
a step of applying a sustain pulse having higher DC voltage than positive DC voltage applied in Set-down of a reset pulse to the sustain electrode; and
a step of applying data pulse of negative polarity to the address electrode.
5. The method according to claim 3 , further comprising a step of sustaining an ON state discharge cell in the previous sub-field to an ON state wall electric charge in address period of the current sub-field by
a step of applying a scan pulse to the scanning electrode in the address period;
a step of applying a sustain pulse having higher DC voltage than positive DC voltage applied in Set-down of a reset pulse to the sustain electrode; and
a step of applying data pulse having 0 voltage to the address electrode.
6. The method according to claim 3 , wherein a step of converting an OFF state discharge cell in the previous sub-field into an ON state wall electric charge in address period of the current sub-field comprises
a step of applying a scan pulse to the scanning electrode in the address period;
a step of applying a sustain pulse having DC voltage equivalent to positive DC voltage applied in Set-down of a reset pulse to the sustain electrode; and
a step of applying data pulse of positive polarity to the address electrode.
7. The method according to claim 3 , further comprising the step of sustaining the an OFF state discharge cell in the previous sub-field to an OFF state wall electric charge in address period of the current sub-field by
a step of applying a scan pulse to the scanning electrode in the address period;
a step of applying a sustain pulse having DC voltage equivalent to positive DC voltage applied in Set-down of a reset pulse to the sustain electrode; and
a step of applying data pulse having 0 voltage to the address electrode.
8. The method according to claim 1 , wherein the step of converting the discharge cell into any one wall electric charge of ON/OFF is achieved by controlling voltage applied to the plurality of scanning electrodes, the plurality of sustain electrodes, and the plurality of address electrodes in accordance with ON/OFF state of a previous discharge cell in address period of a current sub-field.
9. A method of driving a plasma display panel where one frame screen is realized by making a selective combination X numbers of sub-fields SF 1 , SF 2 , SF 3 , . . . , SFX, sustain period of each of which is allowed at the rate of 2 0 :2 1 :2 2 :2 3 : . . . :2 X-1 so as to display multi contrast image on PDP, in the unit of cell for a certain period, wherein only one reset discharge in only first sub-field SF 1 of a respective plurality of discharge cells is caused to occur and the discharge cell in current sub-field is converted into any one wall electric charge of ON/OFF in accordance with ON/OFF state of the discharge cell in previous sub-field.
10. The method according to claim 9 , wherein, in the frame including the plurality of sub-fields, the first sub-field is divided into a reset period, an address period, and a sustain period, and the other sub-fields are divided into address period and sustain period.
11. The method according to claim 9 , wherein the discharge cell in current sub-field is converted into any one wall electric charge of ON/OFF by controlling voltage applied to the plurality of scanning electrodes, the plurality of sustain electrodes, and the plurality of address electrodes in accordance with ON/OFF state of a previous discharge cell in address period of a current sub-field.
12. The method according to claim 11 , wherein the an ON state discharge cell in the previous sub-field is converted into an OFF state wall electric charge in address period of the current sub-field by
a step of applying a scan pulse to the scanning electrode in the address period;
a step of applying a sustain pulse having higher DC voltage than positive DC voltage applied in Set-down of a reset pulse to the sustain electrode; and
a step of applying data pulse of negative polarity to the address electrode.
13. The method according to claim 11 , further comprising sustaining an ON state discharge cell in a previous sub-field to an ON state wall electric charge in address period of the current sub-field by
a step of applying a scan pulse to the scanning electrode in the address period;
a step of applying a sustain pulse having higher DC voltage than positive DC voltage applied in Set-down of a reset pulse to the sustain electrode; and
a step of applying data pulse having 0 voltage to the address electrode.
14. The method according to claim 11 , wherein a step of converting an OFF state discharge cell in the previous sub-field into an ON state wall electric charge in an address period of the current sub-field comprises
a step of applying a scan pulse to the scanning electrode in the address period;
a step of applying a sustain pulse having DC voltage equivalent to positive DC voltage applied in Set-down of a reset pulse to the sustain electrode; and
a step of applying data pulse of positive polarity to the address electrode.
15. The method according to claim 11 , further comprising sustaining an OFF state discharge cell in a previous sub-field to OFF state wall electric charge in address period of the current sub-field by
a step of applying a scan pulse to the scanning electrode in the address period;
a step of applying a sustain pulse having DC voltage equivalent to positive DC voltage applied in Set-down of a reset pulse to the sustain electrode; and
a step of applying data pulse having 0 voltage to the address electrode.