Patent ID: 9025219
Filing Date: 2015-05-05
Classification: H04N

Abstract:
1. An image reading device, comprising: a contact glass on which a manuscript as a reading target is placed; a reading unit provided with an image sensor and configured to read the manuscript placed on the contact glass; a manuscript sensor whose output level varies depending on whether an existence of the manuscript is detected or not; a moving mechanism configured to move the manuscript sensor linearly from a predetermined reference position in an oblique direction with respect to a main scanning direction and a sub scanning direction such that a detection zone of the manuscript sensor passes through a side of the manuscript placed on the contact glass that is parallel to the sub scanning direction and a side of the manuscript that is parallel to the main scanning direction; and a recognizing unit configured to, when performing manuscript size detection, recognize a manuscript length in the main scanning direction and a manuscript length in the sub scanning direction of the manuscript placed on the contact glass, based on an amount of a displacement of the manuscript sensor from the reference position at a time when the output level of the manuscript sensor shows a change.