Abstract: According to the present invention, each printing head includes chips wherein a plurality of nozzles are prepared. The density of dots formed by ejecting ink from the nozzles is detected for each chip, and when a density difference between the chips is smaller than a predetermined value, print data are corrected, and the number of dots is adjusted so as to reduce the density difference. When the density difference is equal to or greater than the predetermined value, first, a drive pulse for the nozzles is modulated and the volume of ink to be ejected for one dot is adjusted so as to reduce the density difference. Thereafter, the print data is corrected, and the number of dots to be formed is controlled so as to reduce the density difference.

Abstract: A printing apparatus conducts inspection associated with printing by changing a relative positional relationship between a line print head and a sheet feeding position for a sheet in a direction perpendicular to a direction in which the sheet is fed, forming an image on the sheet using the line print head a plurality of times, and reading the formed images using a reading unit.

Abstract: A printing apparatus includes a full-line printhead in which a plurality of chips, on each of which a plurality of nozzle arrays are juxtaposed, are arranged in the nozzle arrayed direction, and which prints by the entire width of a printing medium using a plurality of nozzles arranged on the plurality of chips. The printing apparatus discharges ink from a predetermined number of successive nozzles on each nozzle array of each chip toward a printing medium during conveyance, thereby forming a plurality of first patterns corresponding to at least one nozzle array of each chip on the printing medium in the nozzle arrayed direction, reads the plurality of first patterns from the printing medium during conveyance using a sensor, calculates the shift amount of an ink attached position based on the plurality of read first patterns and corrects the attached position of ink based on the shift amount.

Abstract: To provide an inkjet printing apparatus that suppresses occurrence of image deterioration, such as a texture, a moire, and a streak in a printing result. In order for this to be achieved, a level is set up to a overlapping portion of a chip of a print head depending on dot impact accuracy, and a print data distribution rate of each chip in the overlapping portion is determined according to the level.

Abstract: When an image is recorded using a multichip recording head including a plurality of chips each having a plurality of nozzle arrays, a change in image density can occur due to a registration error between chips in an overlapping part where two chips are connected. To suppress the change in image density, input image data is distributed to two chips such that there are dots overlapping each other between the two chips in the overlapping part.

Abstract: The present invention provides a recording apparatus including recording heads each including a plurality of nozzle arrays that are arranged so as to overlap, wherein overlapping portions of the recording heads for two different colors are separated from each other with a distance therebetween in an array direction of nozzles.

Abstract: The present invention provides a recording apparatus including recording heads each including a plurality of nozzle arrays that are arranged so as to overlap, wherein the width with which the overlapping portions of the recording heads for colors that are simultaneously used with a relatively high frequency overlap in an intersecting direction that intersects an array direction of nozzles is smaller than the width with which the overlapping portions of the recording heads for colors that are simultaneously used with a relatively low frequency overlap in the intersecting direction.

Abstract: In a line-head type inkjet printing apparatus that ejects a plurality of types of inks, an inkjet printing apparatus is provided in which the change of its ejection properties different depending on the type of ink is prevented from occurring. The line-head type printing apparatus includes an acquisition unit that counts the ejection number of liquid from each of print heads in each of a plurality of print heads. Furthermore, the printing apparatus compares the ejection number of liquid from each of the print heads counted by the acquisition unit with a threshold value set for each of the print heads. The printing apparatus includes a change unit that can move a holder in the main scanning direction when the counted ejection number of liquid exceeds the threshold value set for the print head.

Abstract: A first humidified gas is supplied through a first supply port to a sheet. A second humidified gas is supplied to a space where nozzles of an inkjet recording head are exposed through a second supply port located at a position closer to the recording heads than the first supply port, to increase atmosphere humidity in the space. The sheet portion having a moisture content increased by the humidification in advance is advanced into the space having the increased atmosphere humidity, to record on the sheet using the inkjet recording head. An amount of humidification with the first humidified gas is set according to at least one recording condition.

Abstract: An apparatus includes: a drying unit to dry a printing medium on which an image was printed using an inkjet head; a humidification unit to humidify the printing medium that was dried by the drying unit so that the moisture content of the printing medium becomes the equilibrium state in the ambient environment; a colorimetric unit to perform colorimetry on the printing medium that was humidified by the humidification unit; and a calibration unit to calibrate printing properties on the basis of the result of colorimetry by the colorimetric unit.

Abstract: A waiting time Ts is decided on the basis of ink type information and ink feed amount information, referring to waiting time table A (Step 6). Along with this, a dried printing paper is carried to and stopped in a waiting area 9 (Step 7), a time period T is measured after stopping, and measurement processing in the next step is delayed until the time period T reaches the waiting time Ts. Then, when the time period T reaches the waiting time Ts, a measuring instrument 10 is used to measure a density of a patch printed on the printing paper (Steps 8 and 9).

Abstract: A printing apparatus includes a plurality of inkjet print heads to which humidified air is supplied to retain the humidity in the print heads. Ink colors for the plurality of heads are arranged in a sequence corresponding to ink characteristics. The plurality of print heads are arranged in a sequence such that a print head configured to eject ink characterized by having a larger amount of volatile components evaporated within a predetermined time is located in a more upstream area.

Abstract: A first reading unit that reads a pattern or an image formed on a sheet by a print unit for recognizing a print unit state, a second reading unit that reads a cut mark formed on the sheet on a downstream thereof, a cutter that cuts the sheet on a downstream thereof, and a reverse unit that reverses the sheet fed to the print unit again are provided. In duplex printing, the sheet where images are sequentially printed on a first surface is led to the reverse unit, the front and rear faces are reversed, and the sheet is fed to the print unit again. The sheet where images and cut marks are sequentially printed on a second surface is cut by the cutter for each piece and discharged. The sheet is cut on the basis of a reading of the cut mark by the second reading unit.

Abstract: A cut mark is recorded in an area between one image and the next image to be printed, and the recorded cut mark is to be detected. When the cut mark cannot be detected, a position of the cut mark is estimated based on information on an already detected cut mark and information on a length of the image printed after said already detected cut mark. A first cut position and a second cut position for cutting off the area are set based on the estimation.

Abstract: In image processing, it is possible to suppress density fluctuation and keep graininess low as well as obtain a good balance of the processing load. More specifically, when dividing multi-valued data and generating two-pass multi-pass printing data, divided multi-valued data that is common to the two passes is generated in addition to the divided multi-valued data for each of the two passes. Moreover, quantized data of that common multi-valued data is reflected on the quantized data for each pass. Furthermore, when generating quantized data, a process of generating common data by the aforementioned data division, or a process of performing quantization first without dividing the multi-valued data and then dividing the quantized 2-pass data is selectively performed according to the printing position on printing medium.

Abstract: In image processing, it is possible to suitably reduce density unevenness and graininess according to the ink used in printing. More specifically, when dividing multi-valued data and generating data for 2-pass multi-pass printing, in addition to divided multi-valued data for each of the two passes, divided multi-valued data that is common to the two passes is also generated. Moreover, quantized data of that common multi-valued data is reflected on the quantized data for each of the passes. Furthermore, when generating the quantized data, the division ratios used when generating the common data using the aforementioned multi-valued data division are set according to the colors of ink used in printing. By doing so, it becomes possible to suitably reduce density unevenness and graininess according to the colors used in printing.

Abstract: When dividing multi-valued data and generating data for two-pass multi-pass printing, in addition to divided multi-valued data that are divided for each of the two passes, divided multi-valued data that is common to both of the two passes is generated. Moreover, quantized data of that common multi-valued data is reflected onto the quantized data for each pass. Furthermore, when generating quantized data, division ratios that are used when generating the common data by the multi-valued data division described above are set according to the image characteristics (whether or not the area is flesh color) of the multi-valued data. Thereby, it is possible to perform high-quality printing regardless of the image characteristics by taking a suitable balance between suppressing density unevenness and suppressing graininess.

Abstract: In image processing it is possible to adequately reduce density unevenness and graininess according to the duty of the image data. More specifically, when dividing multi-valued data and generating 2-pass multi-pass printing data, in addition to the divided multi-valued data for each of the two passes, divided multi-valued data that is common to both of the two passes is also generated. Moreover, the quantized data of that common multi-valued data is reflected on the quantized data of each pass. Furthermore, when generating quantized data, the division ratio when generating common data in the division of multi-valued data is set according to the duty (gradation value) of the multi-valued data. By doing so it becomes possible to adequately reduce the density unevenness and graininess according to the duty of the image data.

Abstract: When the number (M) of passes is smaller than a threshold value, a first processing mode is selected. In the first processing mode, multivalued image data is divided into pieces of multivalued data corresponding to passes and a common multivalued data for a plurality of passes, the pieces of multivalued data are individually binarized to generate pieces of binary data corresponding to the passes, and the common multivalued data is binarized to generate common binary data for these passes. On the other hand, when the number (M) of passes is equal to or larger than the threshold value, a second processing mode is selected. In the second processing mode, multivalued image data is binarized and the binary data is divided into pieces of binary data corresponding to passes with a mask.

Abstract: In a multi-valued printer that uses discontinuous index patterns, if a tone correction table is generated using sampled density patches, a table which is different from a table to be obtained and has no inflection point is obtained, and the print density characteristics after tone correction suffer discontinuity. To solve this problem, an output gamma table used to output measurement patches is set to linearly correct the printer print characteristics. Patches are output and their densities are measured. A reverse table of a “signal value—density” table is generated, and is smoothed using a recursive curve. The smoothed reverse table is finely adjusted to generate an intermediate output gamma table. The generated table undergoes index component correction, thus generating a tone correction table.