Patent ID: 6882374

Claim:
An image projection system comprising: an image display device for display an image to be projected, the image being separated into a plurality of color channels, wherein the image display device sequentially displays the plurality of color channel images in a time division fashion; a light source for projection; an acousto-optical element for separating and refracting light emitted from the light source by a diffraction grating formed by using an ultrasonic wave; and an ultrasonic wave generator for selectively generating, for each color, an ultrasonic wave having such a frequency as to cause the acousto-optical element to generate a refraction angle at which each of the spectral rays of color light corresponding to the color channels to be irradiated on the image display device, and supplying the ultrasonic wave to the acousto-optical element, wherein the displaying of each the color channel on the image display device is performed in synchronism with the selecting of the frequency of the ultrasonic wave generated by the ultrasonic wave generating device.