US Patent 7472977 Printing apparatus and printing method

A printing apparatus executes printing by arranging plural printheads, each including a plurality of print elements in a direction of a print width so as to obtain the print width corresponding to a width of a printing medium and conveying the printing medium in a direction perpendicular to the direction of the print width. The printing positions of part of the print elements of a first printhead in the direction of the print width overlap with part of the print elements of a second printhead in the direction of the print width. The apparatus includes a conveyor for conveying the printing medium, a mutual complementary printer performing mutual complementary printing in the overlap portion by the overlapped print elements, and a time divisional driving controller for dividing the plurality of print elements of each of the plural printheads into a plurality of blocks, with each block composed of a predetermined number of print elements, and for time-divisionally driving the predetermined number of print elements included in each block. The predetermined number differs from a number of print elements included in the overlap portion, and the time divisional driving controller controls the driving sequences of the overlapped print elements of the plural printheads to coincide with each other.