PURPOSE: To surely eliminate condensation by reading a rear face of a read position during condensation eliminating operation and completing the condensation elimination after the read data go all to a white level in a picture reader using a CCD image sensor.
CONSTITUTION: A read circuit 11 including the CCD image sensor reads an original in the unit of line normally and reads the rear white face of the read position without an original during condensation elimination. A full white level detection circuit 12 keeps detecting the white level of all data of one line read by the read circuit 11 during the condensation elimination. When a condensation sensor 15 detects condensation in the standby state, a control circuit 16 drives a fan 13 to light a fluorescent light 14 to start the read of read position rear face. The condensation elimination is continued until it is detected by the full white level detection circuit 12 that the output data of the read circuit 11 go all to white level.