| 摘要 |
PURPOSE:To enhance image quality by making the generation of the moire fringes of a lattice like pattern inconspicuous, by arranging at least one nozzle row at an angle different from that of the other nozzle row. CONSTITUTION:Ink jet heads 11Y, 12C, 13M, 14B for yellow, cyan, magenta and black are arranged at angles of +30 deg., +15 deg., -15 deg., -45 deg. with respect to the moving direction of recording paper 8 and printing points printed by ink jet heads respectively become the positions of Q1, Q2, Q3 in +15 deg.-inclination, the positions R1, R2, R3 in +30 deg.-inclination and the positions S1, S2, S3 in +45 deg.- inclination. In this case, since resolving power at every color does not become constant when the dot pitch P in the direction right-angled to the advance direction of the recording paper 8 is not made the same, if P=PD sintheta is formed when the angle formed by the deflecting direction C of ink droplets and the advance direction of the recording paper is set to theta and the pitch between ink droplets in a deflecting height direction is set to PD, P becomes constant and resolving power at every color can be made constant. |
