Patent ID: 6771397
Filing Date: 2004-08-03
Classification: H04N

Abstract:
An image reader comprising:a CCD sensor for converting an image of an object to be read to image data of electrical signals; a transparent glass for holding the object to be read; a mirror set includes one or more mirrors, and is able to move along the transparent glass, for transmitting the image of the object to be read to the CCD sensor; an illuminating device is moved along the transparent glass together with the mirror set and illuminates the object to be read held to the transparent glass; a carriage member for supporting the mirror set and the illuminating device, which moves at a specified speed along the transparent glass by external driving force, and for indicating an own position by a marker member mounted on its own specified position; a white reference provider for providing white reflected light that serves as a reference for defining a threshold level when the CCD sensor outputs the image data; a home position sensor for detecting the marker member of the carriage member and setting the wait position of the mirror set and the illuminating device; a reading window that is arranged at a specified position in a direction away from the transparent glass with the white reference provider set at the center in a plane defined by the white reference provider as well as the transparent glass and enables the image of the object to be read to be transmitted to the CCD sensor through the mirror set by feeding of the object to be read independently from the object to be read set on the transparent glass; and a drive unit for moving the carriage member at a predetermined speed and setting the position of the carriage member in such a manner that, at the wait time, the reflected light from the white reference provider is guided to the mirror of the mirror set supported on the carriage member, to which the reflected light from the object to be read is first transmitted.