Method and apparatus for controlling the gray scale of plasma display device

A plasma display device comprising at least one pair of electrodes for carrying out a discharge operation, wherein:

• said plasma display device is driven by separating address periods in which display data are written in a common period for each display line in the screen, said display data is so as to accumulate wall charges necessary for sustain discharge from sustain discharge periods in which sustain discharge for light emission is repeated in a common period for each display line, one frame forming an image is constituted by a plurality of subframes each having a specific weight value, numbers of sustain emissions of said plurality of subframes are calculated so at to make a ratio of brightness of said plurality of subframes is calculated so as to substantially correspond with equal a ratio of the specific weight values of said plurality of subframes, wherein a ratio of numbers of sustain emissions of said plurality of subframes does not equal to the ratio of the specific weight values of said plurality of subframes, and the image is displayed on said plasma display device by optionally combining said subframes each having the calculated number of the sustain emissions.

A method of controlling the a gray scale of a plasma display device, wherein said method comprises the steps of:

• forming a frame for an image by a plurality of subframes each having a specific weight value;
• and
• displaying the image on said plasma display device by optionally combining gray levels of said plurality of subframes, wherein each gray level numbers of sustain emissions of said plurality of subframes are calculated so as to make a ratio of brightnesses of each gray level said plurality of subframes is calculated so at to substantially correspond with equal a ratio of the specific weight values of each gray level the specific weight values of said plurality of subframes and a ratio of numbers of sustain emissions of each gray level said plurality of subframes does not equal the ratio of the specific weight values of each gray level the specific weight values of said plurality of subframes.

A plasma display device comprising at least one pair of electrodes for carrying out a discharge operation, wherein:

• said plasma display device is driven by separating address periods in which display data are written in a common period for each display line in the a screen, said display data is so as to accumulate wall charges necessary for sustain discharge from sustain discharge periods in which sustain discharge for light emission is repeated in a common period for each display line, one frame forming an image is constituted by a plurality of subframes each having a specific weight value, and an image on said plasma display device is displayed by optionally combining gray levels of said plurality of subframes, wherein each gray level numbers of sustain emissions of said plurality of subframes are calculated so as to make a ratio of brightness of each gray level is calculated so as to said plurality of subframes substantially correspond with equal a ratio of the specific weight values ofeach gray scale the specific weight values of said plurality of subframes, and a ratio of numbers of sustain emissions of each gray level said plurality of subframes does not equal the ratio of the specific weight values of each gray level the specific weight values of said plurality of subframes.

An apparatus controlling a gray scale of a plasma display device in which a frame for an image is formed by a plurality of subframes having respective, predetermined brightnesses, comprising:

• a memory having set therein a number of sustain emissions individually for, and corresponding to, the predetermined brightness of each individual subframe, numbers of sustain emissions of different subframes bearing a non-linear relationship to the different predetermined brightnesses of the respective, different subframes;
• and
• a controller displaying the image on said plasma display device in accordance with selected subframes to produce a gray scale display of a specific brightness.

A plasma display device comprising at least one pair of electrodes for carrying out a discharge operation, wherein:

• said plasma display device is driven by separating address periods in which display data are written in a common period for each display line in the screen so as to accumulate wall charges necessary for sustain discharge from sustain discharge periods in which sustain discharge for light emission is repeated in a common period for each display line, one frame forming an image is constituted by a plurality of subframes each having a specific weight value, numbers of sustain emissions of said plurality of subframes are calculated so as to make a ratio of brightnesses of said plurality of subframes substantially equal a ratio of the specific weight values of said plurality of subframes, wherein a ratio of numbers of sustain emissions of said plurality of subframes does not equal the ratio of the specific weight values of said plurality of subframes, and the image is displayed on said plasma display device by optionally combining said subframes each having the calculated number of the sustain emissions, and thereby a brightness-drop caused in accordance with increasing the number of sustain emissions is compensated.

A method of controlling a gray scale of a plasma display device, wherein said method comprises:

• forming a frame for an image by a plurality of subframes each having a specific weight value, each of said subframes including an address period and a sustain discharge period, said address period being a common period to carry out address discharge on each selected display line so as to selectively accumulate wall charges for cells formed on said each selected display line, said sustain discharge period being a common period to carry out sustain emissions on said each selected display line, the sustain emissions on said each selected display line being carried out in said sustain discharge period;
• and
• displaying the image on said plasma display device by optionally combining gray levels of said plurality of subframes, wherein numbers of sustain emissions of said plurality of subframes are calculated so as to make a ratio of brightnesses of said plurality of subframes substantially equal a ratio of the specific weight values of said plurality of subframes and a ratio of numbers of sustain emissions of said plurality of subframes does not equal the ratio of the specific weight values of said plurality of subframes, and thereby a brightness-drop caused in accordance with increasing the number of sustain emissions is compensated.

A plasma display device comprising at least one pair of electrodes for carrying out a discharge operation, wherein:

• said plasma display device is driven by separating address periods in which display data are written in a common period for each display line in a screen so as to accumulate wall charges necessary for sustain discharge from sustain discharge periods in which sustain discharge for light emission is repeated in a common period for each display line, one frame forming an image is constituted by a plurality of subframes each having a specific weight value, and an image on said plasma display device is displayed by optionally combining gray levels of said plurality of subframes, wherein numbers of sustain emissions of said plurality of subframes are calculated so as to make a ratio of brightnesses of said plurality of subframes substantially equal a ratio of the specific weight values of said plurality of subframes, and a ratio of numbers of sustain emissions of said plurality of subframes does not equal the ratio of the specific weight values of said plurality of subframes, and thereby a brightness-drop caused in accordance with increasing the number of sustain emissions is compensated.