Method for driving plasma display panel and plasma display device

A plasma display apparatus comprising:

• a plasma display panel that has a plurality of discharge cells each of which has a display electrode pair including a scan electrode and a sustain electrode and performs gradation display by using a structure of a pixel including a plurality of discharge cells, one field including a plurality of subfields each of which has an address period and a sustain period;
• and
• an image signal processing circuit for setting a luminance gradation value for each pixel based on an image signal and for generating image data indicating light emission and no light emission in each subfield in the discharge cells based on the image signal,
• wherein the image signal processing circuit is configured to;
• divide an image display region of the plasma display panel into a plurality of regions,
• calculate an afterimage strength level of each region based on the luminance gradation value set for each pixel in response to the image signal,
• calculate an afterimage strength level of each pixel based on the afterimage strength level of each region, and
• change the luminance gradation value of each pixel based on the afterimage strength level of each pixel.

A plasma display apparatus comprising:

• a plasma display panel including a plurality of discharge cells each of which has a display electrode pair including a scan electrode and a sustain electrode, the plasma display panel being configured to perform gradation display by using a structure of a pixel including a plurality of discharge cells, one field including a plurality of subfields each of which has an address period and a sustain period;
• an image signal processing circuit for setting a luminance gradation value for each pixel based on an image signal and for generating image data indicating light emission and no light emission in each subfield in the discharge cells based on the image signal;
• and
• a sustain pulse generation circuit including a power recovery circuit for raising or decreasing a sustain pulse by resonating an inductor and an inter-electrode capacity of the display electrode pairs, and a clamping circuit for clamping voltage of the sustain pulse on a predetermined voltage, the sustain pulse generation circuit alternately applying, to the display electrode pairs, sustain pulses in a quantity corresponding to a luminance weight set for each subfield in the sustain period,
• wherein the image signal processing circuit divides an image display region of the plasma display panel into a plurality of regions, and calculates afterimage strength level of each region based on the luminance gradation value set for each pixel in response to the image signal, and
• wherein the sustain pulse generation circuit generates a first sustain pulse and a second sustain pulse rising more steeply than the first sustain pulse, and changes a generation ratio between the first sustain pulse and the second sustain pulse based on the afterimage strength level.