Method and a circuit for gradationally driving a flat display device

A method for driving a flat display panel with a gradation of visual brightness, the display panel having a plurality of pixels arranged in plural lines, each line having plural pixels and each pixel having a memory function, the method comprising:

• dividing, with time, each frame to be displayed on said display panel into a respective plurality of successive subframes, the subframes having respective, predetermined weights of brightness gradations and being individually selected to determine the brightness gradation of the respective frame, each subframe being applied at a common timing with respect to all of the plural lines of the display panel;
• further dividing, with time, each of the subframes into respective, first and second successive time periods, each time period having a respective, common timing with respect to all of the plural lines forming the display panel;
• controlling respective timings of a start of the first time period and of an end of the second time period of each subframe to be in common for all of the plural lines forming the display panel;
• setting the time duration of the second time period of each subframe in correspondence to the respective weight of the visual brightness gradation of that subframe;
• in the first time period, and at a common timing for each line of pixels and in succession for the plural lines, selectively forming a memory medium in each selected pixel of the plurality of pixels of said display panel using a first pulse train of a first pulse pitch;
• in said second time period of each subframe, concurrently producing a display at each selected pixel, in which a memory medium was formed, for the time duration of the second time period of the respective subframe and in succession for the plural subframes of each frame using a second pulse train having a second pulse pitch, a respective number of pulses of the second pulse train being supplied for display in the second time period in accordance with the predetermined weights of the brightness gradations thereof;
• and
• repeating the operations of the subframe with the first time period and the second time period so as to display a picture with gradation.

A method of driving a matrix display panel having a plurality of pixels arranged in a plurality of lines, each of said pixels having a memory function, said method comprising:

• dividing a period of a display frame into a plurality of subframes, wherein the plurality of lines are concurrently activated in each subframe, each subframe including respective and successive addressing and displaying periods;
• in each addressing period, addressing a pixel by selectively forming a memory medium, according to said memory function, in a selected pixel of a selected line, sequentially for the plurality of lines, and, in the respective, successive displaying periods, lighting each addressed pixel by concurrently applying sustain pulses to all the pixels, the plurality of successive subframes being allocated respective, predetermined numbers of the sustain pulses in accordance with respective, predetermined weights of visual brightness gradations thereof;
• and
• an order of the respective subframes of a frame being selected arbitrarily in advance of producing a display in accordance with display conditions.

A method of driving a plasma display panel having a plurality of parallel first electrodes, a plurality of second electrodes each of which is disposed between adjacent ones of said first electrodes and a plurality of third electrodes in parallel with each other in a crossing direction relative to said first and second electrodes, a plurality of first cells being formed substantially at respective first positions defined by crossed points of the first electrodes and said third electrodes and a plurality of second cells being formed between the first electrodes and the second electrodes at respective second positions corresponding to the first positions of the first cells, wherein the first cells are selectively addressed corresponding to a picture to be displayed and said second cells display the picture corresponding to the selected ones of the first cells, the method comprising:

• dividing a period of a display frame into a plurality of subframes, each subframe including respective and successive addressing and displaying periods, each said displaying period being independent of the addressing period with respect to all of the first and second cells;
• in each addressing period, addressing said first cells by selectively forming a wall charge in a selected one of said first cells on each sequentially selected one of said first electrodes, and, in the respective, successive displaying period, lighting said second cells corresponding to selected ones of said first cells by concurrently applying sustain pulses to all the second cells, the plurality of successive subframes being allocated respective, predetermined numbers of the sustain pulses in accordance with respective, predetermined weights of visual brightness gradations thereof;
• and
• an order of each one of said subframes is arbitrarily chosen in advance corresponding to a displaying condition.

A method of driving a matrix display panel, formed of a plurality of pixels each having a memory function, comprising:

• dividing with time a period of a frame displaying a single picture into a plurality of subframes, each subframe comprising:
• an address period, executed during a common time for all the pixels, to address a pixel by selectively forming a memory medium in a selected pixel of al the pixels, and
• a display period, independent from said address period, to light said addressed pixel by an application of sustain pulses to all the pixels, each display period of the respective subframe being allocated a predetermined number of said sustain pulses, said allocated number being different for each subframe so as to weight a gradation to said respective subframe,
• whereby a gradation of visual brightness of said lit pixel is determined by selectively performing the address operation in each address period of said divided subframe for each of said pixels for each frame.