Abstract: A display device includes a deformable mirror device wherein grey scales are displayed using a time division modulation process in which the times or sub-frame periods for which each mirror within the deformable mirror array is switched on. The device includes a selection means for ordering selected sub-frame periods or divided sub-frame periods such that the light directed from each mirror is substantially temporally balanced during each frame period of the display device and/or between consecutive frame periods.

Abstract: Video input signals of a field of a first line standard are converted to a second line standard, having a reduced number of lines, via an intermediate line standard. The input signals are passed through one or more delay devices so that the picture information in corresponding parts of adjacent lines is available at any instant. By interpolation of this information there are produced lines of an intermediate standard which are stored. The intermediate standard contains the same number of lines as the first but the interpolated information is contained in the number of lines of the second standard. The excess lines of the intermediate standard may be blank. Output signals of the second standard are obtained by reading-out only the wanted lines of the intermediate standard.In a modification, where the second standard has more lines than the first, lines are added when reading-out the intermediate standard.The apparatus is preferably of the digital type for all steps of the conversion.