Patent ID: 6371592
Filing Date: 2002-04-16
Classification: B41J

Abstract:
A printing apparatus for performing printing on a printing medium by using a printing head, comprising:means for controlling said printing head to form a plurality of patterns, said plurality of patterns being respectively formed corresponding to a plurality of shifting amounts of relative printing positions of a first printing and a second printing to be registered and said plurality of patterns respectively representing optical densities corresponding to said plurality of shifting amounts; optical measuring means for measuring respective optical densities of said plurality of patterns in a measuring operation; means for performing printing registration processing between said first printing and said second printing on the basis of the variation of said optical densities represented by said plurality of patterns measured by said optical measuring means; means for performing a detecting operation distinct from the measurement of said optical densities in the measuring operation by using said optical measuring means; and means for switching controlling characteristics of said optical measuring means between the measuring operation and the detecting operation, respectively, by using a region where a characteristic of said optical measuring means is linear and a region where the characteristic of said optical measuring means is saturated.