IMAGE READER

PROBLEM TO BE SOLVED: To provide an image reader measuring the extent of the fluctuation of a lightness generated caused by a light source having an effect on a result of reading an image while reading the image and correcting the image read on the basis of the value of the measured extent. SOLUTION: The image reader generates the image information of the image on a manuscript MS on the basis of a light irradiated from the light source 21 and diffused and reflected by the manuscript MS in a reading region RA. The image reader presets a reference value at a time when the light source 21 irradiates the light having an ideal intensity to lightness reference information generated on the basis of the light irradiated from the light source 21 and diffracted by a light diffraction unit 25, and uses the difference of the lightness reference information and the reference value as the quantity of the intensity of the light fluctuated. Accordingly, even when the extent of the fluctuation of the intensity of the light is changed during an image reading, corrected image information indicating the image denying the effect of the fluctuation is generated by correcting manuscript-image information in response to the lightness reference information indicating the fluctuation. COPYRIGHT: (C)2011,JPO&INPIT