Patent ID: 7525692

Claim:
An image reading apparatus, comprising: a reader configured to read one side of an original document being conveyed at a reading position; a contact glass comprising a surface configured to contact the original document; a reference disposed at a side of the contact glass opposite to the surface and configured to be movable between the reading position and a standby position, the reference comprising a surface configured to face the reader, the surface having a predetermined color to provide shading data used for a shading correction; a carrier configured to move the reference to the reading position; and guiding members configured to guide the reference moving between the standby position and the reading position above the standby position, wherein the reader is configured to obtain the shading data by reading the predetermined color on the surface of the reference at the reading position and to read the predetermined color on the surface of the reference at a plurality of locations as the reference slides down towards the standby position from the reading position when the carrier is deactivated.