Patent ID: 7782498
Filing Date: 2010-08-24
Classification: H04N

Abstract:
1. An image reading apparatus comprising: an image sensor configured to convert image light of a document into an image signal; an optical unit configured to project the image light of the document on the image sensor; a drive unit configured to drive the optical unit in a sub scanning direction; a document size detecting unit configured to detect a size of the document using the image signal; an image signal processing unit configured to digitally convert the image signal of the image sensor into image data; a power circuit configured to output an operating voltage in standby mode and stop the outputting of the operating voltage in sleep mode; and a power saving control unit configured to move the optical unit to a document size detecting position, different from a home position and a reference white plate reading position, by operating the drive unit before switching the power circuit from the standby mode to the sleep mode, wherein, after the power circuit is switched from the sleep mode to the standby mode by the power saving control unit, the document size detecting unit detects the size of the document.