Image forming apparatus which performs calibration for maintaining image quality

摘要

A luminance value for a second printing medium that has been obtained by reading a pattern image formed on the second printing medium different from a first printing medium is converted into a corresponding density value on the first printing medium. Calibration for the first printing medium can then be performed using the second printing medium.

主权项

1. An image forming apparatus comprising:
an image forming unit which forms a pattern image on a printing medium; a first conversion unit which converts a luminance value obtained from the pattern image formed on a first printing medium into a corresponding density value on the first printing medium, said first conversion unit including a first table used to convert a luminance value for the first printing medium into a corresponding density value on the first printing medium; a second conversion unit which converts a luminance value obtained from the pattern image formed on a second printing medium different from the first printing medium into a corresponding density value on the first printing medium, said second conversion unit including a second table used to convert a luminance value for the second printing medium into a corresponding density value on the first printing medium; a first creation unit which creates a first image processing condition to be applied to form an image on the printing medium by using the density value obtained by said first conversion unit when forming the pattern image on the first printing medium and using the density value obtained by said second conversion unit when forming the pattern image on the second printing medium; an image reading unit which reads the pattern image formed on the first printing medium to obtain the luminance value, and also reads the pattern image formed on the second printing medium to obtain the luminance value; a tone control unit which converts a density value of an image into an amount of applied toner using the first image processing condition; and a table creation unit which creates the second table, wherein said image forming unit forms the pattern image on the first printing medium, said image reading unit reads the pattern image formed on the first printing medium to output the luminance value, said first conversion unit converts the luminance value into the corresponding density value using the first table, said first creation unit creates the first image processing condition based on the density value, said tone control unit converts a density value of the pattern image into an amount of applied toner using the first image processing condition, said image forming unit forms the pattern image on the second printing medium using the amount of applied toner, said image reading unit reads the pattern image formed on the second printing medium to output the luminance value, and said table creation unit creates the second table based on a correspondence between the luminance value and the density value of the pattern image formed on the first printing medium.