The LCOS element driving circuit is provided with a plurality of D/A converters for effecting D/A conversion on pixel data which is fed to each pixel of a LCOS element on a pixel group-by-pixel group basis and delay devices for delaying clock signals to provide timing for each D/A conversion operation. The clocks to be fed to the respective D/A converters are delayed via the delay devices to cause variation in delay time, so that output pixel signals from the D/A converters can be applied to the LCOS element in a synchronized state. This makes it possible to drive the LCOS element at high speed.