Patent ID: 7239352
Filing Date: 2007-07-03
Classification: H04N

Abstract:
1. A method of reading out signal charges from a solid-state image sensor, comprising: a first step of preparing a solid-state image pickup apparatus comprising a solid-state image sensor having a plurality of photosensitive cells arranged in a bidimensional array for converting incident light to electric signal charges, each of the plurality of photosensitive cells including a main region and a subregion smaller in area than the main region, the apparatus executing signal processing on pixel data produced from the signal charges; a second step of causing the solid-state image pickup apparatus to perform preliminary image pickup of a scene; a third step of determining a luminance distribution representative of the scene subject to the preliminary image pickup on a basis of pixel data obtained from a plurality of blocks formed in the bidimensional array to calculate an estimated photometric value that estimates the scene; a fourth step of comparing the estimated photometric value with a predetermined threshold value, above which a dynamic range is effective which defines a reproducible range of the incident light; a fifth step of controlling the image sensor, if the estimated photometric value is smaller than the threshold value, to read out the signal charges generated in the main region and the subregion of each of the photosensitive cells while mixing the signal charges with each other for the photosensitive cell; and a sixth step of controlling the image sensor, if the estimated photometric value is not smaller than the threshold value, to read out the signal charges generated in the main region and the subregion of each of the photosensitive cells individually from each other.