PURPOSE: To obtain a picture quality being equal to an interlace display by using a liquid crystal light valve, and also, to prevent the generation of blurring of an animation caused by a memory effect by using the same picture element for both an odd field and an even field, and also, vibrating it by a half picture element portion or a one-picture element portion on a screen.

CONSTITUTION: As for a liquid crystal light valve, a one-field display liquid crystal light valve 3 for displaying both an odd field and an even field on the same picture element is used. In this state, a video of each field displayed on this liquid crystal valve 3 is moved by a half picture element portion or a one-picture element portion by allowing it to synchronise with a vertical synchronizing signal of a video signal in the longitudinal direction on a screen. In such a way, each picture element is rewritten at every field, a fault caused by a memory effect of a liquid crystal comes not to occur, and also, an interlace display is executed as a result, and a picture quality being equal to a video which has been brought to interlace by a CRT can be obtained.