Patent ID: 7336393
Filing Date: 2008-02-26
Classification: H04N

Abstract:
1. A color image reading apparatus comprising: a light source to irradiate a document relatively moving and scan said document; a first photoelectric conversion device to receive optical image information from said document and a background of said document by said light source and obtain first electric signal information at a first speed; a second photoelectric conversion device to receive said optical image information and obtain second electric signal information at a second speed higher than said first speed; a first document size detection unit to detect, on the basis of said first electric signal information from said first photoelectric conversion device, a boundary between said document and said background of said document and detecting a document size; a second document size detection unit to detect, on the basis of said second electric signal information from said second photoelectric conversion device, said boundary between said document and said background of said document and detect said document size; and a control unit to control, at the time of forward scanning of said document by said light source, so as to detect said document size by said second document size detection unit.