| 摘要 |
PROBLEM TO BE SOLVED: To correct light quantity unevenness that is caused in a sub scanning direction by varying the quantity of light from a light source unit during scanning of one document.SOLUTION: In an image forming apparatus 1, light emitted from a light source unit 211 is reflected toward a CCD sensor 209 by a white reference plate 219 for each scanning of a scan line and received by the CCD sensor 209, thereby obtaining light quantity data that becomes a light quantity reference for each scanning of the scan line. Light quantity data obtained by scanning of one scan line are compared with light quantity data obtained by scanning of a preceding scan line to determine light quantity data that become a light quantity reference. A shading correction value with the determined light quantity data as the light quantity reference is determined as a shading correction value for image data obtained by scanning of one scan line, and the image data obtained by scanning of the one scan line are corrected with the shading correction value. The determination and the correction are performed for each of image data obtained for each scanning of a scan line. |
