Method and device for controlling a matrix screen displaying gray levels using time modulation

摘要

A process and device for controlling a matrix screen displaying gray levels, wherein during the line time T activation signals are delivered to the columns of the screen for a time depending on the gray level i of the image point in question and equal to (T/N).Nil, where Oi. ltoreq.mN, the Nils forming a strictly increasing sequence of i of first term zero and of last term lower than or equal to N, the Nils being so selected as to obtain a predetermined distribution for the light intensities of the different gray levels.PPApplication to the control of microdot or liquid crystal matrix screens.