A scanner is provided with an illumination lamp for emitting light to a first side of a document from one side of a transfer path and a CCD image sensor for receiving light reflected from the first side of the document, and a CIS provided in a document feeder is provided with an LED for emitting light to a second side of the document from the other side of the transfer path and a line sensor for receiving light reflected from the second side of the document. The illumination lamp is a xenon lamp, and the LED is a white LED having emission characteristics different from those of the xenon lamp. To the CIS, a filter is attached, which brings emission characteristics of light emitted from the LED onto a document closer to those of light emitted from the illumination lamp onto the document.