Patent ID: 7130573

Claim:
An image forming apparatus, comprising: a transporting unit adapted to transport a recording material; an image forming unit adapted to form an image on an image bearing member; a transfer unit adapted to transfer the image on the image bearing member to a recording material which is transported by the transporting unit; a synchronization controlling unit adapted to stop the recording material which is transported by the transporting unit and to restart the transport of the recording material to synchronize the recording material with the image on the image bearing member; a reading unit disposed along a transport path of said transporting unit, adapted to read a surface of the recording material as a picture consisting of plural pixels each indicating density degree; and a judging unit adapted to judge the type of a recording material on the basis of the picture of the surface of the recording material read by the reading unit, wherein the judging unit judges the type of the recording material on the basis of the picture of the surface of the recording material read by the reading unit during a period of time where the synchronization controlling unit stops the recording material.