DEVICE FOR CORRECTING QUANTITY OF AMBIENT LIGHT, METHOD FOR CORRECTING QUANTITY OF AMBIENT LIGHT, ELECTRONIC INFORMATION APPARATUS, CONTROL PROGRAM AND READABLE RECORDING MEDIUM

摘要

The present invention corrects the insufficient peripheral light amount due to the lens shading and correcting the non-uniformity of light amount at the periphery due to a distortion resulting from a precision of the lens or a poor mounting precision of the lens. A peripheral light amount correction circuit is structured by an image synchronization signal generation circuit, a coordinate conversion circuit and a luminance value correction computing circuit. An integrated value of luminance values is calculated at the coordinate conversion circuit to extract light amount information. Coordinate values to be input to the luminance value correction computing circuit are generated based on an integrated/averaged value of the light amount information. In the luminance value correction computing circuit, peripheral light amount correction functions are converted based on the input coordinate values from the coordinate conversion circuit to perform appropriate correction on the input image.