Patent ID: 7710387

Claim:
An image display device comprising: a backlight: a liquid crystal panel for displaying images by irradiating light from the backlight comprising: a single optical sensor for detecting light from the backlight and environmental light to output an electric signals; pixel electrodes for driving a liquid crystal; switching elements for switching the pixel electrodes; and a single transparent substrate on which the optical sensor, said pixel electrodes and said switching elements are formed by laminating thin films; and a control unit for controlling backlight irradiation and image display, which obtains a surface reflection luminance of the liquid crystal panel from the outputted electric signals of the optical sensor acquired in a first condition that the backlight is turned off, obtains a minimum luminance and a maximum luminance of the liquid crystal panel from the outputted electric signals of the optical sensor acquired in a second condition that the backlight is turned on, and calibrates currently set luminance gradation based on a total minimum luminance and a total maximum luminance of the liquid crystal panel, the total minimum luminance being obtained by adding the surface reflection luminance and the minimum luminance and the total maximum luminance being obtained by adding the surface reflection luminance and the maximum luminance.