摘要:
An ink-jet printing apparatus, for printing an image based on image information on a printing medium by relatively moving an ink-jet printhead, detects the temperature of the ink-jet printhead by using a head temperature detection unit and outputs it to a driving frequency determination unit. The driving frequency determination unit acquires temperature information in units of pages of image information or predetermined image areas. If the acquired temperature is equal to or higher than a predetermined temperature, the driving frequency of the ink-jet printhead is decreased when a predetermined unit of the image information is printed.
摘要:
An ink jet printer includes a distance adjust mechanism for adjusting in two steps a distance between a liquid nozzle-formed face of a print unit and the recording surface, and a unit having first and second cleaning members with different free end positions, lengths and/or thicknesses are arranged movable relative to the face and adapted to wipe a substance adhering to the face off of the face with a predetermined engagement condition. The substance is wiped off of the face by the first and second cleaning members having different engagement conditions when the face is a first distance from a recording surface, and is wiped off with the engagement condition of a wipe portion of the first cleaning member virtually equal to the engagement condition of a wipe portion of the second cleaning member associated with the first distance when the face is a second distance from the medium. Further, a height difference between the cleaning members is set almost equal to the distance the face is moved by the distance adjust mechanism.
摘要:
When recording a gradation pixel by performing pseudo-halftone processing, the occurrence of unevenness in the density in the recorded image is suppressed. For that purpose, when recording a pseudo-halftone image using dot patterns, a dot-pattern table storing a plurality of different dot patterns is provided for each gradation value. One dot-pattern table is selected from N dot-pattern tables based on gradation-value information for each pixel. One dot pattern is selected from the selected dot-pattern table, based on position information indicated by the pixel, and recording is performed using the selected dot pattern. It is thereby possible to prevent the concentrated use of a particular nozzle of a recording head, and suppress the occurrence of unevenness in the density due to characteristics of the specific nozzle.
摘要:
When recording a gradation pixel by performing pseudo-halftone processing, the occurrence of unevenness in the density in the recorded image is suppressed. For that purpose, when recording a pseudo-halftone image using dot patterns, a dot-pattern table storing a plurality of different dot patterns is provided for each gradation value. One dot-pattern table is selected from N dot-pattern tables based on gradation-value information for each pixel. One dot pattern is selected from the selected dot-pattern table, based on position information indicated by the pixel, and recording is performed using the selected dot pattern. It is thereby possible to prevent the concentrated use of a particular nozzle of a recording head, and suppress the occurrence of unevenness in the density due to characteristics of the specific nozzle.
摘要:
By using an ink jet head, which has for each color two parallel columns of nozzles arranged side by side in the main scan direction and shifted from each other by one-half the pitch at which the nozzles are arranged in each column, odd-numbered rasters and even-numbered rasters making up an image are printed by the two nozzle columns. The registration between the odd- and even-numbered rasters is secured during the printing to produce an image with high print quality. For that purpose, the ink ejection timing between the two raster groups is shifted by a predetermined interval to form a plurality of adjustment patterns; the adjustment patterns printed are checked and, according to the check result, an adjustment value for the ink ejection timing between the two ink nozzle columns is entered; and the entered adjustment value is stored to be reflected on the actual printing operation. To facilitate the adjustment pattern check, the plurality of adjustment patterns have a dot distribution with a blue noise characteristic at a resolution at which the printing apparatus can print.
摘要:
An apparatus and method are provided to enable high speed printing of an image with high resolution while suppressing degradation of image quality due to white stripes and density variations. In an ink jet printing apparatus using a multi-pass printing system, the same scan print area is divided at a predetermined pitch and the printing duties of the divided areas determined by the thinning out mask pattern are set to different values. In regard to the same scan print area formed by a plurality of the main scans, the divided areas corresponding to the ends of the print head have their printing duties set smaller than those of the divided areas on the inner side of the ends of the print head.
摘要:
At least defective printing element information about a defective printing element among a plurality of printing elements is stored in an EEPROM. A complementary printing element for masking printing data corresponding to the defective printing element indicated by the defective printing element information and complementarily printing the printing data corresponding to the defective printing element is determined. The printing data of the defective printing element is printed using the determined complementary printing element.
摘要:
With an ink jet head having for each color two parallel columns of nozzles arranged shifted by one-half the pitch, odd-numbered rasters and even-numbered rasters are printed by the two nozzle columns. The registration between the odd- and even-numbered rasters is secured during the printing to produce a high quality image. The ink ejection timing between the two raster groups is shifted by a predetermined interval to form adjustment patterns; the adjustment patterns are checked and, according to the check result, an adjustment value for the ink ejection timing between the two ink nozzle columns is entered, and the entered adjustment value is stored to be reflected on the actual printing operation. To facilitate the adjustment pattern check, the adjustment patterns have a dot distribution with a blue noise characteristic at a resolution at which the printing apparatus can print.
摘要:
The present invention reduces the granularity of the dots for the entire density range by optimally setting formation amounts of a low-density dot and of a high-density dot per unit area. For this purpose, the formation amounts of the low-density dot and of the high-density dot in accordance with the density level are determined in such a way that as the density level rises, the formation amount of the low-density dot is gradually increased up to a first peak amount (200%) and, after reaching the first peak, gradually decreased, and in a range of density levels higher than a predetermined density level at which the low-density dot is formed to a specified amount (200%), as the density level rises, the formation amount of the high-density dot is gradually increased up to a second peak amount (100%) smaller than the first peak amount.
摘要:
The present invention provides a printing apparatus and method that can prevent the image grade from lowering. A print head is provided with a plurality of printing elements to print dots on N adjacent rasters and dots on M adjacent columns under different conditions by causing the print heads perform a plurality of (P) main-scanning operations in a main-scanning direction and transporting a printing medium at least once in a sub-scanning direction. A plurality of dot arrangement patterns used for the same level of image data are periodically changed. The plurality of dot arrangement patterns are such that within each period when the patterns are repeatedly used, the number of dots formed in each of said N rasters are equalized, whereas the number of dots formed in each of said M columns are equalized.