Patent ID: 7398026
Filing Date: 2008-07-08
Classification: G03G

Abstract:
1. A method of controlling an image density, comprising: forming a plurality of predetermined gradation patterns of powder having different amounts of powder transferred continuously on a surface of a detection target; detecting optically the predetermined gradation patterns; acquiring data of the detected patterns and data arithmetically processed based on the data of the detected patterns; extracting a regular reflection light component by separating a regular reflection output from the detected patterns into the regular reflection light component and a diffuse reflection light component; converting the regular reflection light component into a normalized value; acquiring a first-order linear relation between the normalized value and an amount of toner transferred within a range in which detection of an amount of toner transferred by the regular reflection of light is possible; storing, in a memory, data obtained by detecting the predetermined gradation patterns and necessary for maintaining accuracy in density control with fewer patterns than the predetermined gradation patterns to a level equal to an accuracy in density control with the predetermined gradation patterns; and using the data stored in the memory when controlling the image density with the fewer patterns.