Patent ID: 7702236

Claim:
A digital image acquisition device having an image acquisition sensor, a shutter, one or more optical elements for focusing an image on the sensor, and an aperture disposed between at least one of said one or more optical elements and said shutter, the device including a light source located in a body of the device, and being arranged to periodically activate the light source only when said aperture is closed such that said sensor is substantially unexposed to ambient light, and to derive a map of defects in the sensor or on the surface of the sensor, or both, from a calibration image acquired by the sensor when illuminated by the light source and when said sensor is substantially unexposed to ambient light due to said aperture being closed, and the device is further arranged to correct an acquired image based on the map of defects, and to construct a second defect map based on a second calibration image, and to correct the corrected image in accordance with said second defect map.