Abstract: 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.

Abstract: A CCD output signal processing method includes the steps of sampling a CCD output signal supplied from a CCD in synchronism with a transfer clock to thereby generate sampled CCD output data within an n-th section corresponding to one pixel (n is an arbitrary integer), expanding the sampled CCD output data to a Fourier series which has a basic waveform having aa period substantially corresponding to a reciprocal of a frequency of the transfer clock, and calculating an amplitude of the basic waveform from first-order Fourier coefficients included in the Fourier series, the amplitude of the basic waveform being a corrected amplitude of the CCD output signal supplied from the CCD. There is provided a CCD output signal processing apparatus which implements the above-mentioned method.