Patent ID: 7742180

Claim:
An image reading apparatus comprising: a scanner adapted to read an image of an original; a document feeder adapted to feed said original to a platen; a dust or dirt detector adapted to detect presence of dust or dirt on said platen; an original size detector adapted to detect a size of said original; and a controller adapted to perform a read-while-feed operation in which the original, while being fed by said document feeder, is read by said scanner placed at one of a plurality of predetermined positions, corresponding to different sizes of originals, on the basis of the size of said original detected by said original size detector, and to perform a stationary reading operation in which the original is held at a fixed position on the platen and read while moving said scanner, if said dust or dirt detector at the one of the plurality of predetermined positions corresponding to the size of said original detected by said original size detector detects presence of dust or dirt.