Visible Moiré interference is eliminated by alternately shifting the phase of th e horizontal sync signal or video signals such that the phase of each video line, and hence the phase of the resulting Moiré interference associated with that video l ine, is also alternately shifted. The phase of the Moiré interferences are shifted such that persistence of vision in the human eye averages oppositely phased phosphor intensity variations occurring on alternating scan lines and/or vertical fields. When viewed by a user of the CRT, optical cancellation of the Moiré interference patt erns results.
METHOD AND APPARATUS FOR CANCELLATION OF MOIRE INTERFERENCE IN COLOR CATHODE RAY TUBE DISPLAYS