Patent ID: 7631974

Claim:
An image display method for displaying an image by using an image display device configured to modulate incident light with a spatial optical modulating element according to an input video signal so as to project an image onto a screen via a projection lens, wherein difference values, a plurality of illuminance ranges, and brightness correction characteristic data are used, where the difference values are defined as values representing a magnitude of an influence exerted by the image display based on the input video signal upon an illuminance of an ambient environment according to a brightness component of the input video signal and are set so as to correspond to the brightness component based on a result of measuring the magnitude of the influence previously, the illuminance ranges are set by dividing an extent of the illuminance of the ambient environment, and the brightness correction characteristic data are prepared for changing the brightness component of the input video signal according to each of the illuminance ranges; the method comprising the steps of: detecting the brightness component of the input video signal so as to select the difference values based on the detected value; measuring the illuminance of the ambient environment repeatedly at regular time intervals by using an illuminance sensor; selecting one of the plurality of illuminance ranges based on illuminance detection values obtained by previous and current measurements and the selected difference values; selecting the brightness correction characteristic data according to the selected illuminance range so as to correct the brightness component of the input video signal based on the brightness correction characteristic data; and projecting an image based on the input video signal.