Patent ID: 8262191
Filing Date: 2012-09-11
Classification: B41J

Abstract:
1. A printing apparatus configured with a mounted print head comprising ejection ports through which different amounts of ink in the same color are ejected, the ejection amounts being equal to or smaller than 5 pl, the print head ejecting ink for printing through the ejection ports, the printing apparatus comprising: an ejection failure state sensing unit for carrying out first and second ejection failure state sensing processes, the first ejection failure state sensing process for sensing an ejection state of ink ejected through predetermined ejection ports which have ejection opening areas smaller than that of all other ejection ports formed in the print head, ink being ejected through the predetermined ejection ports without being ejected through the other ejection ports in the first ejection failure state sensing process, the second ejection failure state sensing process for sensing an ejection state of ink ejected through all the ejection ports formed in the print head, wherein the second ejection failure state sensing process is carried out less frequently than the first ejection failure state sensing process, and wherein when one of the ejection ports is determined to be in an inappropriate ejection state by the first ejection failure state sensing process or the second ejection failure state sensing process, compensation printing is carried out so as to compensate for dots to be formed by the one ejection port in the inappropriate ejection state using at least one different ejection port for printing with compensation.