摘要:
In a printer, when difference in ejection characteristic among nozzles appears as density non-uniformity and the way of letting the density non-uniformity appear is different depending upon kind of image, proper density correction is performed. Specifically, the kind of image to be printed is judged, and when the kind of image is a halftone image according to the judgment, a density correction table corresponding to the halftone image is selected and used to perform the density correction. Also when the kind of image is judged to be a solid image (without a portion of the halftone image), a proper table is selected similarly and used to perform the density correction.
摘要:
An apparatus and method capable of obtaining an output characteristic of the print unit and determining a correction value for an output density, without using an expensive scanner. To realize this, a nozzle array consisting of a plurality of nozzles provided in the print head is divided into a plurality of nozzle blocks [a] to [d] and each of patches is formed by using the nozzles of the same nozzle block allocated to the patch. The patches are printed in a size and shape that allows the densities of the patches to be optically detected by the density sensor. A test pattern comprising these patches is measured by the density sensor to make a density correction for each nozzle of the print head.
摘要:
An ink-jet printing apparatus and an ink-jet printing method allow the printing of an image with high quality without causing a change in ink color formed on the printing medium while keeping the printing conditions constant regardless of changing of the number of nozzles to be printed and the amount of transferring of the printing medium. This printing is performed, for example, by restricting use of the number of nozzles, which belong to a nozzle row located on an upstream side in the sub-scan direction, before changing the amount of transferring of the printing medium; and restricting use of the number of nozzles, which belong to the nozzle rows located on a downstream side in the sub-scan direction, after changing the amount of transferring of the printing medium.
摘要:
The object of the present invention is to provide an ink jet printing apparatus which can realize both a high speed printing and a high quality printing without color deviations when each of the print areas is printed in a plurality of scans by a plurality of print heads ejecting different kinds of ink. For this purse, this invention has a controller for controlling for each print head independently widths and positions of active nozzle groups in the print heads, the active nozzle groups representing those of the plurality of nozzles in the print heads which are used for printing, wherein the controller controls the widths and positions of the active nozzle groups according to a set printing condition.
摘要:
A liquid ejection head according to the present invention includes a single liquid supplying port to which a liquid is supplied, a plurality of liquid supplying passages having one end in communication with the liquid supplying port, a plurality of common liquid chambers that are in communication with the other ends of the liquid supplying passages, respectively, and a plurality of ejection port groups which are in communication with the common liquid chambers via liquid channels and from which liquid droplets are ejected. A cross sectional area or length of the liquid supplying passage in communication with the ejection port group having a larger sum of opening areas of the ejection ports is set smaller than that of the liquid supplying passage that is in communication with the ejection port group having a smaller sum of opening areas of the ejection ports.
摘要:
An ink jet printing apparatus including: a print unit having a polarity of ejection outlet arrays, for ejecting ink,; a scan unit for scanningly moving the print unit relative to the print medium in a main scan direction; and a feed unit for feeding the print medium relative to the print unit in a direction which is different from the main scan direction, wherein an image is formed on the print medium while repeating a scanning operation of the scanning unit and a feeding operation by the feeding unit. The apparatus also includes an information obtaining unit for obtaining image information; and a selecting unit for selecting at least one of the ejection outlet arrays to effect printing for the image data in a predetermined area, on the basis of the information obtained by the information obtain unit about image formations.
摘要:
A printing apparatus can reduce degradation in print quality of a printed image, notably in a highlight portion or an intermediate gradation portion, in the case where the image is printed by forming dots of a plurality of sizes. Specifically, data causing larger and smaller cyan ink droplets, respectively, to be ejected is independently subjected to a conversion to n-value process. Thus, the data for larger ink droplets is present in a portion of printing data which corresponds to the highlight portion or intermediate gradation portion of the image. During printing, larger dots are formed in this area, thereby making it difficult to perceive possible stripes caused by the offset of the positions at which smaller droplets impact a sheet.
摘要:
In an image processing method, on the basis of input image data with respect to a target pixel, independent multi-level data (g0, g1) corresponding to respective plural species of dots which are different in at least one of a density and a diameter are generated, and then data (O0, O1) relating to an amount of generation of the dots with respect to the target pixel are generated on the basis of a relationship between the generated independent multi-level data (g0, g1) corresponding to the plural species of dots. The image processing method is effective in performing design having a high degree of flexibility in proper use of a relatively high power dot (high density dot or large dot) and a relatively low power dot (low density dot or small dot) and can realize obviation or alleviation of an occurrence of granulation or an apparent frame caused due to the relatively high power dot.
摘要:
In an ink jet print head used in a serial type ink jet printing apparatus according the present invention, a portion of the nozzle column is given a wider nozzle-to-nozzle interval than those of other portions of the nozzle column so that the width in the line feed direction of each image area printed in a single printing scan by the ink jet print head is longer than a distance that a print medium is moved by one line feed. In this serial print head, the width of each image area printed by a single printing scan can be made a predetermined amount longer than the line feed distance at all times. As a result, the adjoining image areas printed by separate printing scans overlap each other at their boundary portions by a predetermined amount.
摘要:
In an image processing method, on the basis of input image data with respect to a target pixel, independent multi-level data (g0, g1) corresponding to respective plural species of dots which are different in at least one of a density and a diameter are generated, and then data (O0, O1) relating to an amount of generation of the dots with respect to the target pixel are generated on the basis of a relationship between the generated independent multi-level data (g0, g1) corresponding to the plural species of dots. The image processing method is effective in performing design having a high degree of flexibility in proper use of a relatively high power dot (high density dot or large dot) and a relatively low power dot (low density dot or small dot) and can realize obviation or alleviation of an occurrence of granulation or an apparent frame caused due to the relatively high power dot.