Method and apparatus for matrix addressing opto-electric displays

Claim 1

A display apparatus comprising: (1) An electro optic display having a layer of display material between two dielectric substrates, a first series of m electrodes on one substrate and a second series of n electrodes on the other substrate arranged to define a matrix of m×n elements across which electric signals may be applied to cause an observable display effect; (ii) means for generating a first series of m different reference electrical waveforms, means for applying a different one of the m different waveforms simultaneously to each electrode in the first series of electrodes; (iii) means for generating a second series of electrical waveforms different from one another and from each of the first series of waveforms; (iv) means for selecting waveforms from the second series of waveforms for application to each electrode in the second series of electrodes, the selected waveform being related to the waveforms on the first series of electrodes and to the desired information to be displayed at each element associated with each electrode in the second series of electrodes; (v) means for applying the selected waveforms simultaneously to the second series of electrodes concurrently with the waveforms applied to the first series of electrodes; (vi) whereby an rms voltage less than a display effect threshold voltage is maintained across selected elements and an rms voltage greater than the display effect threshold is maintained across the remaining elements to collectively display the desired information.