Patent ID: 8169554

Claim:
A projection display apparatus comprising: a light source to emit a light beam; an illumination optical system through which the emitted light beam undergoes linear polarization; at least one liquid crystal display device to optically modulate the linearly-polarized light beam based on an input signal; a projection optical system to enlarge the optically-modulated light beam and project the enlarged light beam onto a screen; and a light-beam controller provided on an optical axis of the optically-modulated light beam, to allow the optically-modulated light beam to travel therethrough to reach the screen or cut off the optically-modulated light beam, under control by a control signal, wherein the light-beam controller has a plurality of driving zones on which the optically-modulated light beam is incident, the driving zones being provided in a direction corresponding to a vertical scanning direction of pixels of the liquid crystal display device, the light-beam controller being driven per driving zone in a specific order of the driving zones at a timing of vertical scanning of the pixels under control by the control signal that is generated based on a vertical synchronization signal detected from the input signal, thus the optically-modulated light beam being allowed to travel through the light-beam controller or cut off when the optically-modulated light beam is incident on the driving zones at the timing of the vertical scanning.