Patent ID: 7167658
Filing Date: 2007-01-23
Classification: G03G

Abstract:
1. An image forming apparatus, comprising: an image forming section for forming and outputting a predetermined gradation patch pattern image on a transfer paper; a scanner section, for reading an image on a document, which reads the gradation patch pattern image on the transfer paper and performs color measuring on the gradation patch pattern image to obtain a color value of the gradation patch pattern image formed on the transfer paper; a sensor for reading the gradation patch pattern image and outputting a sensor output value corresponding to the read gradation patch pattern image; and a control section for correcting reading characteristics of said sensor based on the sensor output value of said sensor and the color value of the gradation patch pattern image formed on the transfer paper obtained by the scanner section; wherein the control section calculates a sensor correction coefficient by carrying out a regression calculation with the color value of the gradation patch pattern image formed on the transfer paper and the sensor output value obtained by reading the gradation patch pattern image and converts the sensor output value to a color value using the sensor correction coefficient to correct the sensor reading characteristics.