Patent ID: 9050824
Filing Date: 2015-06-09
Classification: B41J

Abstract:
1. A printing control apparatus that performs control for printing an image using a print head that includes a plurality of ejection port arrays including at least a first ejection port array in which a plurality of ejection ports which eject ink of the same color are arranged in a certain array direction and a second ejection port array which is adjacent to the first ejection port array in the array direction and in which a plurality of ejection ports which eject ink of the same color are arranged in the array direction and in which the plurality of ejection port arrays are arranged in the array direction such that one ejection port array and another ejection port array adjacent to each other in the array direction are arranged at different positions in the array direction and different positions in a cross direction, which is crossing to the array direction, so that N ejection ports, N being larger than zero, located at an end of the one ejection port array on a side of the other ejection port array in the array direction and N ejection ports located at an end of the other ejection port array on a side of the one ejection port array in the array direction form an overlap portion capable of performing printing in the same region of a print medium, the printing control apparatus comprising: a scanning unit configured to scan the print head and the print medium in the cross direction relative to a unit region of the print medium; a conveying unit configured to convey, between operations of the scanning performed by the scanning unit, the print medium in a conveying direction, which is crossing to the cross direction, by a distance corresponding to a length smaller than a length of a range of the print head in which the ejection ports are arranged; and an ejection control unit configured to perform control such that ink is ejected onto the unit region at a certain printing ratio in each of a plurality of operations of the scanning, wherein the conveying unit conveys the print medium such that the overlap portion between the first and second ejection port arrays corresponds to a first unit region in a first operation of the scanning among the plurality of operations of the scanning performed by the scanning unit, such that N ejection ports in a first non-overlap portion other than the overlap portions between the plurality of ejection port arrays correspond to a second unit region in a second operation of the scanning different from the first operation of the scanning among the plurality of operations of the scanning performed by the scanning unit, and such that N ejection ports in a second non-overlap portion other than the overlap portions between the plurality of ejection port arrays correspond to the second unit region in a third operation of the scanning different from the first and second operations of the scanning among the plurality of operations of the scanning performed by the scanning unit, wherein, in order to print, in the cross direction, a plurality of pixel columns including a plurality of pixels arranged in the array direction in the first and second unit regions, the ejection control unit performs control such that, (i) when the ejection ports of the first and second ejection port arrays in the overlap portion perform printing in the first unit region in the first operation of the scanning, M of the N ejection ports of the first ejection port array in the overlap portion, M being equal to or larger than zero but smaller than or equal to N, closest to the second ejection port array in the array direction do not eject ink, N−M ejection ports of the first ejection port array in the overlap portion farthest from the second ejection port array in the array direction eject ink at a first printing ratio, N−M of the N ejection ports of the second ejection port array in the overlap portion closest to the first ejection port array in the array direction do not eject ink, and M ejection ports of the second ejection port array in the overlap portion farthest from the first ejection port array in the array direction eject ink at the first printing ratio, (ii) when the ejection ports in the first non-overlap portion perform printing in the second unit region in the second operation of the scanning, K of the N ejection ports in the first non-overlap portion, K being equal to or larger than zero but smaller than or equal to N, closest to the second non-overlap portion in the array direction do not eject ink and N−K ejection ports in the first non-overlap portion farthest from the second non-overlap portion in the array direction eject ink at a second printing ratio, and (iii) when the ejection ports in the second non-overlap portion perform printing in the second unit region in the third operation of the scanning, N−K of the N ejection ports in the second non-overlap portion closest to the first non-overlap portion in the array direction do not eject ink and K ejection ports in the second non-overlap portion farthest from the first non-overlap portion in the array direction eject ink at the second printing ratio, wherein M and K continuously increase or decrease as a position of the pixel column in the first and second unit regions, respectively, changes in the cross direction, and wherein, when the position of the pixel column in the first and second unit regions is a certain position in the cross direction, M and K are different values.