Patent ID: 7643069

Claim:
A device for adjusting exposure of an image sensor, comprising: an average luminance value calculation unit configured to calculate a first total average luminance value of pixels that are output from the image sensor; a first exposure control unit configured to control an exposure value of the image sensor based on a previously set exposure value; a correction exposure value calculation unit configured to calculate a correction exposure value by multiplying the previously set exposure value by a ratio of a target luminance value to the first total average luminance value; and a first luminance value difference calculation unit configured to receive from the average luminance value calculation unit a second total average luminance value of pixels that are output from the image sensor whose exposure value is controlled based on the correction exposure value and to calculate a difference between the second total average luminance value and the target luminance value; wherein the first exposure control unit is further configured to receive the correction exposure value from the correction exposure value calculation unit and to control the exposure value of the image sensor based on the correction exposure value, and wherein the first exposure control unit is further configured to compare the first difference with a first comparison luminance value and to control the exposure value of the image sensor so that the first difference becomes smaller than the first comparison luminance value.