Abstract: A smooth, uniform image is produced by minimizing the occurrence of satellites of secondary color and dispersing landing positions of the satellites as uniformly as possible. For this purpose, the printing operation performed so that satellites of the two inks (cyan and magenta ink, foe example) ejected toward the same pixel are separated and landed on opposite sides of the main dots on the same pixel. This makes the distribution of satellites uniform and makes individual satellites less noticeable, maintaining the uniformity of an image.

Abstract: A printing apparatus includes a plurality of print element arrays each with a plurality of print elements arranged therein. The printing apparatus prints an image by time division driving in which the plurality of print elements in each print element array are divided into a plurality of blocks and in which the print elements are driven for every block. The amount of misalignment among the print element arrays in an arrangement direction of the print elements is acquired. A print element group used for printing in at least one print element arrays is changed in accordance with the acquired misalignment amount to correct the misalignment among the print element arrays. A driving order of the blocks is changed in accordance with the misalignment amount. Even in the case of the time division driving, the misalignment of the dot formation positions can be eliminated.

Abstract: By subtracting a first parameter related to the printing position deviation inherent to the printing head from a second parameter that is obtained by actually measuring the printing position deviation in a state where the printing head is mounted on the printing apparatus, a third parameter related to the printing position deviation inherent to the printing apparatus is acquired. When a new printing head is mounted on the printing apparatus, a new second parameter is computed from the third parameter and a first parameter that is of the new printing head. By this procedure, it is possible to hold down a time required for actual measurement of the printing position deviation and consumables, and even when the printing head is exchanged, it becomes possible to stably output a uniform image free from the printing position deviation.

Abstract: A plurality of ejection portions are divided into groups, each containing at least one ejection portion, so that the suction-based recovery operation can be performed for each group independently. Since the number of ejection portions contained in each group differs, if an ink flow resistance varies among the different groups, simultaneous suction-based recovery operations can be done by using a common suction pump, without having to sequentially perform the suction-based recovery operations under an optimum pump driving condition. For this purpose, inner diameters of a plurality of ink discharge tubes running from a plurality of cap units, which cap a plurality of print head units having different numbers of ejection portions, to the common pump are differentiated. This allows different flows to be produced in different ink discharge systems, thus generating desirable ink flows for individual ink supply systems.

Abstract: A plurality of ejection portions are divided into groups, each containing at least one ejection portion, so that the suction-based recovery operation can be performed for each group independently. Since the number of ejection portions contained in each group differs, if an ink flow resistance varies among the different groups, simultaneous suction-based recovery operations can be done by using a common suction pump, without having to sequentially perform the suction-based recovery operations under an optimum pump driving condition. For this purpose, inner diameters of a plurality of ink discharge tubes running from a plurality of cap units, which cap a plurality of print head units having different numbers of ejection portions, to the common pump are differentiated. This allows different flows to be produced in different ink discharge systems, thus generating desirable ink flows for individual ink supply systems.

Abstract: A region for quantization having a value lower than the value B is assumed as having little influence by Bk data on the pixels in this region. Thus, in order to prioritize the optimization of the granularity at the start of the input of GY data, the LUT having a combination of GY and gy as an input as an input is used to perform separation quantization. On the other hand, since a region having a value equal to or higher than the value B requires the use of Bk data, the LUT having only a combination of Bk and GY as an input as an input is used to perform quantization. As a result, the number of types of pieces of ink data referencing the table can be 2, thus suppressing an increase in the table size.

Abstract: The present invention relates to a printing position adjusting method capable of performing dot adjustment value acquisition processing that can accommodate diversified user needs of recent years, and a printing system capable of achieving the adjusting method. The printing position adjusting method according to the present invention provides a plurality of types of dot adjustment value acquisition processing capable of acquiring an adjustment value for matching printing positions, and enables selection of a single appropriate dot adjustment value acquisition processing type among the plurality of types of dot adjustment value acquisition processing according to the type of the print medium to be used. Consequently, a user will be able to suitably execute dot adjustment value acquisition processing with high accuracy in correspondence with the desired high level of quality.

Abstract: In the ink-jet printing apparatus, the influence of displacements of printing positions caused by the excessive conveyance of a printing medium to the resultant image when the rear end of the printing medium exits from a nip portion between the roller pair in a conveying mechanism. More specifically, in the printing operation for the rear end portion of the printing medium in which the printing medium exits from the roller pair, the guide shaft for supporting the carriage is lifted at a position wherein a head-medium distance is changed to widen a distance between the printing had and the printing medium (S402). Thereby, the displacement of the landing position caused by the excessive conveyance of the printing medium is inconspicuous because of the variations of the landing positions due to the widening of the head-medium distance.

Abstract: In an inkjet printing method of performing printing on a printing medium by ejecting inks from a printing head configured to eject chromatic inks and an achromatic ink while moving the printing head, high-quality printing with few boundary stripes produced when the amount of inks is large is realized without complicated control being performed. To this end, print data in a boundary and the vicinity thereof is divided into unit regions, and for each unit region, performed are (A) a first reduction processing which determines a hue of the unit region based on amounts of the chromatic inks, and reduces the amount of chromatic inks applied to the unit region according to the determined hue; and (B) a second reduction processing which reduces an amount of achromatic ink based on the amount of achromatic ink applied to the unit region.

Abstract: The present invention relates to a printing position adjusting method capable of performing dot adjustment value acquisition processing that can accommodate diversified user needs of recent years, and a printing system capable of achieving the adjusting method. The printing position adjusting method according to the present invention provides a plurality of types of dot adjustment value acquisition processing capable of acquiring an adjustment value for matching printing positions, and enables selection of a single appropriate dot adjustment value acquisition processing type among the plurality of types of dot adjustment value acquisition processing according to the type of the print medium to be used. Consequently, a user will be able to suitably execute dot adjustment value acquisition processing with high accuracy in correspondence with the desired high level of quality.

Abstract: An ink jet printing apparatus and an ink jet printing method are provided which are capable of minimizing image impairments caused by a bias of satellite positions even when an odd-numbered-pass bidirectional multi-pass printing is performed. To this end, in an odd-numbered-pass bidirectional printing, a mask pattern, in which print permitted pixels and print non-permitted pixels are arranged such a way that a percentage of pixels in which predetermined two inks are permitted to be printed by scans in different directions is higher than a percentage of pixels in which the predetermined two inks are permitted to be printed by scans in the same directions, is used. This increases the probability of satellites of the two types of the inks printed in the same pixels being printed on both sides of main dots, thus allowing a uniform image to be produced even by an odd-numbered-pass bidirectional printing.

Abstract: An ink jet recording apparatus is structured to perform discharges in the capping status when preliminary discharges are performed in a shot number larger than a predetermined number, and perform discharges in a cap or a preparatory port other than the cap when the preliminary discharges are performed in a shot number less than the predetermined number. With the structure thus arranged, it is made possible to implement the suppression of the mist generation due to the preliminary discharges, and to make the time of recording on a recording medium shorter as well.

Abstract: A recording apparatus includes a recording unit configured to record a first dot and a second dot having a diameter smaller than that of the first dot on a recording medium, and a scanning unit configured to move the recording unit in a scanning direction. A recording resolution of the second dot in the scanning direction is lower than a recording resolution of the first dot in the scanning direction.

Abstract: There is provided an inkjet printing apparatus which executes a proper recovery operation in accordance with the demounting time period of an ink tank and information of the ink tank. In the inkjet printing apparatus of this invention, the demounting time period and information of the ink tank are used as parameters for determining the condition of a recovery operation after the ink tank is once demounted and thereafter mounted again. Since recovery is done in consideration of the degrees of ink evaporation and an increase in viscosity, wasteful ink consumption can be suppressed while a necessary recovery operation is performed.

Abstract: In a printing apparatus which prints an image on a printing medium by alternately performing printing of an image on the printing medium by using a printing unit and conveyance of the printing medium relative to the printing unit, the conveyance amount in conveyance is corrected by using first and second parameters for correcting the conveyance amount in accordance with different factors. This makes it possible to correct the conveyance amount in accordance with the deviation of the printing position due to the different factors.

Abstract: The present invention reduces image deterioration such as density nonuniformity when recording is performed using a recording head having two ejection orifice rows that eject a predetermined achromatic ink, for example, gray ink. For this purpose, the distance between two ejection orifice rows that eject a predetermined achromatic ink is larger than the distance between two ejection orifice rows that eject a predetermined chromatic ink.

Abstract: A recording apparatus includes a recording unit configured to record a first dot and a second dot having a diameter smaller than that of the first dot on a recording medium, and a scanning unit configured to move the recording unit in a scanning direction. A recording resolution of the second dot in the scanning direction is lower than a recording resolution of the first dot in the scanning direction.

Abstract: For a recording apparatus capable of supplying a plurality of different color inks to a plurality of recording element substrates, when a condition for performing maintenance on a first recording element substrate is met, it is determined whether or not to perform maintenance on a second recording element substrate according to how close the second recording element substrate is to meeting the condition. Since maintenance is performed on the first and second recording element substrates in such a manner, unnecessary maintenance operations will be prevented from being carried out multiple times within a short period of time. Accordingly, the total amount of time required for maintenance is reduced.

Abstract: For a horizontally arranged print head, in which nozzle rows are arranged parallel with a scanning direction of the print head, two of a plurality of ink colors used, which have the greatest hue difference, are selected. Between the nozzle rows for these two colors, at least two nozzle rows for other colors are arranged so that the nozzle rows for the two colors have a large inter-nozzle-row distance. The resulting print head is used for printing. If cyan, light cyan, magenta, light magenta, yellow, and black are used as ink colors, the light cyan, black, yellow, and light magenta inks are arranged between the cyan and magenta inks, having a great hue difference.

Abstract: In an ink-jet printing apparatus which includes a plurality of printing heads, each having an array of ink discharging elements, preliminary discharge of driving the elements of at least one printing head is performed a predetermined number of times. The printing head for which the preliminary discharge is to be performed is switched in a predetermined cycle. In performing the preliminary discharge, switching of the printing head is so controlled as to perform preliminary discharge a desired number of times for all the elements of the printing heads by repeating the cycle.