Patent ID: 8259370

Claim:
An image reading device comprising: a reading unit including a light source and a predetermined number of light receiving elements aligned in a first direction, the light source irradiating light onto an object to be read, at least a part of the predetermined number of light receiving elements receiving light reflected from the object, the reading unit outputting line data representing a line image on the object; a conveying section that conveys the reading unit in a second direction perpendicular to the first direction; a first light amount determining section configured to determine a first light amount to be emanated from the light source; a second light amount determining section configured to determine a second light amount to be emanated from the light source based on the first light amount determined by the first light amount determining section; a pre-scan section configured to perform a pre-scan to gather information about the object by controlling the conveying section to move the reading unit in the second direction and further controlling the reading unit to read the object on a line-by-line basis with a first resolution while emanating the second light amount from the light source; and a main-scan section configured to perform a main-scan to read the object by controlling the conveying section to move the reading unit in the second direction and further controlling the reading unit to read the object on a line-by-line basis with a second resolution while emanating the first light amount from the light source, control operations by the main-scan section being performed after completion of control operations by the pre-scan section, wherein the first light amount determining section is configured to control the reading unit to read a white reference member with the second resolution and to output a first set of line data, the first light amount being determined based on the first set of line data.