Display arrangement

A display arrangement, comprising:

• a flat panel display device (5) having an array of pixels;
• and
• a driving circuit arrangement for driving each of the pixels by means of a two level signal, the two level signal switching at a multiple of a frame rate so as to produce the visible effect of a multi-intensity image, wherein said driving circuit includes
• a plurality of intensity level registers, one for each intensity level to be reproduced,
• means for applying a source signal for a pixel of interest to a first intensity level register corresponding to a source intensity level,
• means for setting the pixel value to a first intensity level if a register content of said first intensity level register is greater than or equal to a given threshold value and then adding a first value to the register content of said first intensity level register, the first value being a differential between the first intensity level and the source intensity level,
• means for setting the pixel value to a second intensity level if the register content of said first intensity level register is less than the threshold value and adding a second value to the register contents of said first intensity level register, the second value being a differential between the second intensity level and the source intensity level, and
• means for adding a random number to the register content of said first intensity level register.

A method of driving a flat panel display comprising an two dimensional array of pixels using a driving circuit arrangement to obtain a multi-intensity picture display, said method comprising:

• i) providing a driving circuit arrangement for driving each of the pixels based on a two level signal,
• ii) causing the driving circuit to produce said two level signal at a multiple of the frame rate,
• iii) providing in the driving circuit arrangement a plurality of intensity level registers, one for each intensity level to be reproduced,
• iv) applying a source signal for a pixel of interest to a first intensity level register corresponding to a source intensity level,
• v) setting the pixel level to a first intensity level if a register content of the first intensity level register is greater than or equal to a threshold value and, if so, adding a first value to the register content of the first intensity level register, the first value being a differential between the first intensity level and the source signal intensity,
• vi) setting the pixel level to a second intensity level if the register content of the first intensity level register is less than the threshold value and, if so, adding a second value to the register content of the first intensity level register, the second value being a differential between the second intensity level and the source signal intensity, and
• vii) adding a random number to the register content of the first intensity level register.