Flat display

Claim 1

A drive system for a flat display of first and second substrates, each having a main surface and plural electrodes disposed in parallel on the main surface and with the respective main surfaces thereof disposed in parallel, spaced relationship and with the respective electrodes thereof in perpendicular relationship so as to define a matrix of plural crossing points between the respective electrodes of the first and second substrates, at least one crossing point defining a display cell and serving as a pixel of the display, said drive system comprising: a brightness level controlling circuit for changing the respective brightness levels of frames to be displayed on said flat display, in which a single frame to be so displayed is segmented temporally into a plurality of sub-frames corresponding to scanning lines, said brightness level controlling circuit changing the brightness level by variously selecting some of the subframes; an address current detecting circuit, operatively connected to said pluralities of electrodes, for detecting a value of an address current which is consumed for producing a display on said flat display; a comparator circuit which compares the value of the consumed address current, detected by said address current detecting circuit, with a reference current value and produces a comparison output; and an address frequency control circuit, operatively connected to said electrodes, which selectively disables the sub-frames in response to the comparison output of the comparator, to thereby control an address frequency, and thus a number of address pulses applied to each of said pluralities of electrodes associated with a display frame, and thereby the brightness level of the display.