Patent ID: 7413314

Claim:
An optical system comprising: a light source; a light modulator modulating light emitted from the light source to a certain image; a driving part comparing a detected image with luminance information of the certain image and controlling the light modulator based on the comparison to produce the certain image and outputting luminance information of the certain image; a projector projecting the certain image; a screen on which the projected image is formed; a projection iris controlling an amount of light projected from the light modulator onto the screen; an iris controller connected to the driving part and receiving the luminance information of the certain image from the driving part and controlling the projection iris corresponding to the luminance information of the certain image; an illumination iris controlling the amount of light emitted from the light source to the light modulator, and wherein the iris controller controls at least one of the projection iris and the illumination iris corresponding to the luminance information; wherein the illumination iris and the projection iris each comprise at least three sectors for determining an opening range of the iris, and the iris controller receives the luminance information in real time and controls the sectors in real time corresponding to the luminance information.