METHOD FOR CORRECTING IMAGE SIGNAL DETERIORATED BY FLARE AND IMAGE READING UNIT

A method for correcting image information deteriorated by flare generated in an image reading unit having a light source for irradiating a document, a scanning system optically scanning the document irradiated by the light source and outputting the image information, and a reference image having a predetermined density distribution is provided. The method includes the following steps of: optically scanning the reference image irradiated by the light source, the scanning system outputting reference image information corresponding to the reference image; generating a function denoting a response with respect to the deterioration of the image information caused by the flare based on the reference image information obtained by the scanning system; optically scanning the document irradiated by the light source by the scanning system; and performing a deconvolution operation in which the image information obtained by the scanning system and the above function are used.