Image reader

A method for controlling an image reader including an optical reading section that reads reflected light from a light source;

• a first reference density member that is installed outside an original document reading position, and that is read by said optical reading section for acquiring data for correcting shading;
• a second reference density member that is fixedly installed at said original document reading position so as not to block the optical path from said light source and a conveyance path of original documents, and that is read by said optical reading section for acquiring data for correcting the light amount of said light source, said method comprising the steps of:
• setting a first correction coefficient, based on first reference data obtained by reading said first reference density member in advance, and read data obtained by reading said first reference density member at startup of the original document reading;
• setting a second correction coefficient for every read page, based on second reference data obtained by reading said second reference density member in advance, and read data obtained by reading said second reference density member during each time interval between two successive pages of the original documents fed to said original document reading position one page after another while the original documents are read;
• and
• performing shading correction according to said first correction coefficient, as well as performing light amount correction according to said second correction coefficient, for each of the pages of the original document image read by said optical reading section.

A control program for controlling, by a computer, an image reader including an optical reading section that reads reflected light from a light source;

• a first reference density member that is installed outside an original document reading position, and that is read by said optical reading section for acquiring data for correcting shading;
• a second reference density member that is fixedly installed at said original document reading position so as not to block the optical path from said light source and a conveyance path of original documents, and that is read by said optical reading section for acquiring data for correcting the light amount of said light source, said control program comprising the steps of:
• setting a first correction coefficient, based on first reference data obtained by reading said first reference density member in advance, and read data obtained by reading said first reference density member at startup of the original document reading;
• setting a second correction coefficient for every read page, based on second reference data obtained by reading said second reference density member in advance, and read data obtained by reading said second reference density member during each time interval between two successive pages of the original documents fed to said original document reading position one page after another while the original documents are read;
• and
• performing shading correction according to said first correction coefficient, and performing light amount correction according to said second correction coefficient corresponding a read page, for each of the pages of the original document image read by said optical reading section.