Addressing a matrix of bistable pixels

A method of addressing a matrix of bistable pixels which are defined by areas of overlap between members of a first set of electrodes on one side of a layer of ferroelectric liquid crystal material and members of a second set of electrodes, which cross the members of the first set, on the other side of the material, in which method, for each electrode of the first set, a blanking signal is applied thereto to effect blanking of corresponding pixels and thereafter a unipolar select pulse of width T is applied thereto to effect selection of the corresponding pixels, and for each electrode of the second set, a pair of contiguous pulses is applied thereto, each pair of contiguous pulses being selected to be either of a first kind in which the first pulse of the pair is of a first polarity and the second pulse of the pair is of the opposite polarity, wherein the second pulse is of length at least T and applied simultaneously with the application of the select pulse, or of a second kind in which the first pulse of the pair is of the opposite polarity and the second pulse of the pair is of the first polarity, wherein the second pulse is of length at least T and applied simultaneously with the application of the select pulse, so as to effect writing to the corresponding pixels, the select pulses being applied to the electrodes of the first set one by one at intervals of nT, and each pair of contiguous pulses being applied as a charge-balanced waveform to each electrode of the second set during each interval of length nT, the end of which coincides with the end of the corresponding application of the select pulse to the electrode of the first set, wherein n is an integer greater than two and the first pulse of each pair of contiguous pulses has a length which is greater than T.