Plasma display device and driving method of plasma display panel
View Patent ↗A stable address discharge is generated and number of unlit cells is decreased without heightening the voltage necessary for generating an address discharge. For this purpose, the device includes a plasma display panel and a driving circuit for driving the plasma display panel, in which the driving circuit drives the plasma display panel having a sub-field group formed of two or more continuous sub-fields for controlling addressing provided in one field period, so as not to generate sustain discharge in the discharge cell not causing sustain discharge and also in the subsequent sub-fields, the discharge cell is initialized by applying a ramp waveform voltage descending gently to the scan electrode, the lowest voltage of the ramp waveform voltage of the sub-field included in the sub-field group is made different from the lowest voltage of the ramp waveform voltage of the sub-field not included in the sub-field group.
1. A plasma display device comprising:
a plasma display panel having a plurality of discharge cells, each of the discharge cells having a display electrode pair formed of a scan electrode and a sustain electrode; and
a driving circuit for driving the plasma display panel having a plurality of sub-fields provided in one field, each of the sub-fields having:
an initializing period for initializing the discharge cell by applying a gently descending ramp waveform voltage to the scan electrode;
an address period for addressing selectively the discharge cells to be discharged; and
a sustain period for causing sustain discharge by a number of times corresponding to a luminance weight in the discharge cells performing the address discharge in the address period,
wherein the driving circuit drives the plasma display panel so as to have (i) a first sub-field group including a number of the plurality of sub-fields and (ii) a second sub-field group including another number of the plurality of sub-fields in one field, and each sub-field of the second sub-field group has a luminance weight which is greater than each of the luminance weights of the first sub-field group,
wherein the driving circuit drives the plasma display panel so as not to use gray scale values having two or more continuous non-emitting sub-fields positioned between a sub-field having a largest emitting luminance weight and a first sub-field in the first sub-field group, and
wherein the driving circuit drives the plasma display panel by controlling the address period so as not to generate the sustain discharge in the discharge cell not causing sustain discharge and also in a subsequent sub-fields in the second sub-field,
wherein the driving circuit drives the plasma display panel in such a manner that a lowest voltage of the descending ramp waveform voltage of each sub-field included in the second sub-field group is made to be higher than a lowest voltage of the descending ramp waveform voltage of each sub-field included in the first sub-field group.
2. A driving method of a plasma display panel for driving a plasma display panel having a plurality of discharge cells, each of the discharge cells having a display electrode pair formed of a scan electrode and a sustain electrode, the method comprising:
driving the panel having a plurality of sub-fields provided in one field, each of the sub-fields having:
an initializing period for initializing the discharge cells by applying a gently descending ramp waveform voltage to the scan electrode;
an address period for addressing selectively the discharge cells to be discharged; and
a sustain period for causing sustain discharges by a number of times corresponding to a luminance weight in the selected discharge cells performing the address discharge in the address period;
driving the plasma display panel so as to have: (i) a first sub-field group including a number of the plurality of sub-fields, and (ii) a second sub-field group including another number of the plurality of sub-fields in one field, and each sub-field of the second sub-field group has a luminance weight which is greater than each of the luminance weights of the first sub-field group;
driving the plasma display panel so as not to use gray scale values having two or more continuous non-emitting sub-fields positioned between a subfield having a largest emitting luminance weight and a first sub-field in the first sub-field group; and
driving the plasma display panel in such a manner that a lowest voltage of the descending ramp waveform voltage of each sub-field included in the second sub-field group is made to be higher than a lowest voltage of the descending ramp waveform voltage of each sub-field included in the first sub-field group.