Patent ID: 7460088

Claim:
A plasma display apparatus, which performs a gradated display using a subfield method, comprising: a plasma display panel having a plurality of scan electrodes and a plurality of sustain electrodes extending in the same direction and being arranged adjacent to each other, and a plurality of address electrodes extending in a direction intersecting at that of the plurality of scan electrodes and the plurality of sustain electrodes; sustain pulse cycle changing circuitry detecting a display load ratio of each subfield of a plurality of subfields, and shortening a sustain pulse cycle of each respective subfield of the plurality of subfields in which the detected display load ratio of the respective subfield is less than a predetermined value; and adaptive subfield number changing circuitry calculating a vacant time in a display frame generated by said shortening, judging whether a subfield is to be added according to the calculated vacant time, and determining the number of subfields in the display frame according to said judging.