Patent ID: 9498955
Filing Date: 2016-11-22
CPC Classification: B41J,G06K

Claim Text:
1. A printing device comprising a printing head having a nozzle row on which are formed a plurality of nozzles aligned in a first direction and configured to discharge ink, the nozzle row including a one end side nozzle group which is a plurality of nozzles of one end side of the nozzle row, an other end side nozzle group which is a plurality of nozzles of an other end side of the nozzle row, and a center nozzle group which is a plurality of nozzles of the nozzle row and does not correspond to the one end side nozzle group and the other end side nozzle group; a control unit configured to convey a print medium in the first direction, configured to move the printing head in a second direction that intersects the first direction, and configured to perform printing by discharging the ink from the nozzles onto the print medium during movement of the printing head; and an ink volume determining unit configured to, by referencing a color conversion table for converting a color system used by image data that expresses an image to a color system of the ink discharged by the printing head, determine an ink volume within a designated upper limit value for each pixel of the image data, the control unit being configured to, during a first movement which is the movement, discharge the ink on a designated area on the print medium from the nozzles included in the center nozzle group and the other end side nozzle group while the control unit is configured not to discharge the ink on the designated area from the nozzles included in the one end side nozzle group, and configured to, during a second movement which is the movement the next time after the first movement, discharge the ink on the designated area from the nozzles included in the center nozzle group and the one end side nozzle group while the control unit is configured not to discharge the ink on the designated area from the nozzles included in the other end side nozzle group, the control unit being configured to control discharging of the ink by the nozzles by allocating to the nozzles pixels for which discharge or non-discharge of the ink has been determined based on the ink volume, when the ink volume determining unit, among a pre-defined first color conversion table using a first upper limit value for the upper limit value, and a pre-defined second color conversion table using a second upper limit value higher than the first upper limit value for the upper limit value, references the pre-defined second color conversion table to determine the ink volume, the control unit being configured to allocate pixels to the nozzles included in the center nozzle group and the other end side nozzle group in correspondence to the first movement, and allocate pixels to the nozzles included in the center nozzle group and the one end side nozzle group in correspondence to the second movement, and when the ink volume determining unit references the first color conversion table to determine the ink volume, the control unit being configured to allocate pixels to the nozzles included in the one end side nozzle group, the center nozzle group, and the other end side nozzle group respectively in correspondence to each time of the movement.