Patent ID: 7817196

Claim:
An imaging device, comprising: an optical sensor having a two-dimensional array of photosensitive pixels; a lens operable to direct an image onto the optical sensor, wherein the array of photosensitive pixels are scanned to output data representative of a shading intensity pattern superimposed on the image; a memory for storing data, including: at least one base value of the shading intensity pattern of at least one photosensitive pixel of the array, increments of change of the shading intensity pattern between pixels across the array in both rows and columns, and second derivatives of the increments of change of the shading intensity pattern along individual pixels across the array in at least the vertical direction; a first circuit for determining compensation factors for the photosensitive pixels from the at least one base value, increments of change of the shading intensity pattern between pixels across the array in both rows and columns and the second derivatives of the increments of change of the shading intensity pattern along individual pixels across the array in at least the vertical direction; and a second circuit for combining the determined compensation factors with data obtained from individual photosensitive pixels of the array, wherein the combination of the determined compensation factors and data obtained from individual photosensitive pixels in the array provides correction for the shading intensity pattern superimposed on the image.