Patent ID: 6747766
Filing Date: 2004-06-08
Classification: H04N

Abstract:
A color image reader comprising:a reading object holder, having plate shape and which can transmit light, for holding a subject to be read; a lighting device for illuminating the subject to be read on the reading object holder; a reducing lens for providing convergence to the image light from the reading object; a 3-line CCD sensor for receiving the image light with convergence given by the reducing lens and outputting three electrical signals corresponding to the image light; and a lateral chromatic aberration correction circuit for storing only parameters representing an approximate expression or linear expression for correcting color deviation in all pixel positions in a main scanning direction, for designating one output signal of the three output signals outputted from the 3-line CCD sensor to the reference, for comparing the two remaining output signals with the output signal used for the reference, and for providing a predetermined correction to the two remaining output signals, wherein the 3-line CCD sensor contains three sets of line sensors arranged on the same plane in parallel to one another, and are positioned in such a manner that the image light passing through the center of the reducing lens impinges on the line sensor located at the center of the three sets of the line sensors, and wherein the lateral chromatic aberration correction circuit finds the difference of the outputs corresponding to the optional pixel in each of the two remaining outputs with respect to the output of the center line sensor to the optional pixel for the three outputs outputted by the 3-line CCD sensor.