Patent ID: 7755813

Claim:
An image reading apparatus comprising: an automatic document feeder for feeding documents one by one so that each document passes through a reading position; an image reading unit for reading an image of each of the documents traveling through the reading position; a transparent member provided between the document traveling through the reading position and the image reading unit; a document guide member, with a specified thickness, provided on the transparent member in an upstream side of the reading position; and a mechanism for reciprocating either the transparent member or the document guide member substantially in parallel to a document feeding direction while the document guide member is in contact with the transparent member; wherein if a downstream edge with respect to the document feeding direction of the document guide member is at a distance x 1 from the reading position and if the document guide member or the transparent member is moved by a distance x 2 relative to each other, the distances x 1 and x 2 are in relationship of x 1 <x 2 .