Patent ID: 7304772

Claim:
An image-reading apparatus comprising: a document size sensor configured to sense a size of a document placed at a predetermined position; an image-reading section configured to read an image of the document in the size sensed by the document size sensor; a processing section configured to perform predetermined processing on image data corresponding to the image of the document read by the image-reading section; a power supply section including a first power supply which supplies power to the image processing section, and a second power supply which supplies power to the document size sensor, the second power supply being supplied with power from the first power supply and being able to be turned on and off independently of turn-on and turn-off of the first power supply; and a power supply control section configured to control turn-on and turn-off of the second power supply; wherein the power supply control section turns off the second power supply in a power save mode assumed in a standby state to save power consumption.