Patent ID: 7543903
Filing Date: 2009-06-09
Classification: B41J

Abstract:
1. A method for diagnosing an image-forming device, the method comprising: forming a non-diagnostic image on a surface with the image-forming device; forming diagnostic marks on the surface using distinct image-forming points of the image-forming device; and sensing the diagnostic marks, wherein the diagnostic marks are formed in a pattern, wherein the pattern follows a formula C=(s+1)*(MOD(r, m)+m*n); where C=the column in which a diagnostic mark is to be formed for a particular corresponding row r of at least one image-forming point, m=the number of unmarked rows between marks in each column plus one, n=the nth diagnostic mark in a row for a particular image-forming point, where n begins with 0, and s=a designated spacing between columns containing the diagnostic marks.