Abstract: In printing apparatus, when printing near the end of a print media with a printhead having nozzles, a controller causes a print drive to produce a large print media advance movement together with the use of a different group of nozzles from that used for the rest of the print media. This avoids printing art effects as the print media leaves a pinch in a media feed. In one embodiment the number of nozzles used for printing in the end region is reduced, and the centre of the group of nozzles is simultaneously shifted in the direction of print media advance. The size of the print media advance is also changed in the end region. The printing mask used is also changed.

Abstract: A method of printing a document using one of a plurality of print modes, the method comprising: (i) notionally dividing a digital image of the document into sectors; (ii) for each sector, comparing one or more properties of the luminosity of pixels within each sector with one or more threshold values; (iii) using the comparison of (ii) to determine whether each sector is likely to show an image defect if printed at a lower image quality print mode; (iv) selecting a print mode such that all sectors are determined not to be likely to show an image defect; (v) printing the document using the determined print mode.

Abstract: An inkjet printer is used to print on media an amplitude modulated (AM) halftoning pattern where dot size is varied to create different tones. Different sized dots are formed on the media by depositing different patterns of adjacent drops that coalesce into the different sized dots.

Abstract: A printer is configured to manage a signal-to-noise ratio of a signal produced by a sensor scanning a print test pattern. The print test pattern is printed while controlling ink density printed by each of one or more pens. Each ink density is selected so that the signal-to-noise ratio exceeds a threshold as the print test pattern is scanned. Pens within the printer are aligned or otherwise maintained by adjusting nozzle firings as indicated by data obtained from the signal during the scanning.

Abstract: The invention relates to a method of printing on a media comprising: providing a printhead 300 comprising a plurality of nozzles (301, . . . , 310, . . . , 319, . . . ) defining a print zone, at least one 310 of the nozzles of the print zone being faulty, the print head comprising within the print zone one or more healthy zones 371, 372; submitting a first region 281 of the media to N print zone passes; and, submitting a second region 282 of the media to M print zone passes using a healthy zone to overlap a faulty nozzle, at least two of the M passes being separated by an advance of the media relative to the printhead; producing alternate first and second regions when printing on the media; whereby M>N and N>0.

Abstract: A printer is configured to manage a signal-to-noise ratio of a signal produced by a sensor scanning a print test pattern. The print test pattern is printed while controlling ink density printed by each of one or more pens. Each ink density is selected so that the signal-to-noise ratio exceeds a threshold as the print test pattern is scanned. Pens within the printer are aligned or otherwise maintained by adjusting nozzle firings as indicated by data obtained from the signal during the scanning.

Abstract: A method of determining an angle between a first direction of movement of a print head and a second direction of movement of a print media, comprises: printing an array of markings on said print media, said array of markings extending along said first direction and along said second direction; traversing a sensor device along said first direction, and detecting a signal corresponding to said plurality of markings; identifying a plurality of peaks in said sensor signal as a plurality of data co-ordinates; and obtaining an angle data describing an angle between said plurality of data co-ordinates and a reference data.

Abstract: A method and apparatus for servicing a pen in an inkjet printing device includes receiving a print job, determining a level of print quality required for the print job, detecting the operating characteristics of a number of nozzles to be used to print the print job; and, in the event that the operating characteristics of the nozzles are sufficient to meet the level of print quality, printing the print job. A maintenance procedure may be scheduled in the event that an individual one of the nozzles is not fully functional. In addition, the maintenance procedure may be scheduled to be performed during a time when the inkjet printing device is idle.

Abstract: In printing apparatus, when printing near the end of a print media with a printhead having nozzles, a controller causes a print drive to produce a large print media advance movement together with the use of a different group of nozzles from that used for the rest of the print media. This avoids printing artefacts as the print media leaves a pinch in a media feed. In one embodiment the number of nozzles used for printing in the end region is reduced, and the center of the group of nozzles is simultaneously shifted in the direction of print media advance. The size of the print media advance is also changed in the end region. The printing mask used is also changed.

Abstract: Computation and data-storage are minimized in both accounting for element condition and reallocation of print tasks away from subnominal elements. An accounting function maintains an element-condition tabulation partly in a cumulative form—representing element stability directly without later interpretation. A reallocation distributes print burden from a subnominal element to plural other elements without making a new mask. Rather, entries for a poor element in a current mask are shifted prospectively and quickly to other elements serving the same pixel rows.

Abstract: A method of determining an angle between a first direction of movement of a print head and a second direction of movement of a print media, comprises: printing an array of markings on said print media, said array of markings extending along said first direction and along said second direction; traversing a sensor device along said first direction, and detecting a signal corresponding to said plurality of markings; identifying a plurality of peaks in said sensor signal as a plurality of data co-ordinates; and obtaining an angle data describing an angle between said plurality of data co-ordinates and a reference data.

Abstract: The procedure consists of the catalytic thermal decomposition of a carbamate in the presence of natural or synthetic carbamates as catalysts. Isocyanates with high yields and high reaction speeds are formed selectively.

Abstract: The time required to perform servicing operations may be substantially reduced by application of different criteria on different pens of a printing mechanism. The servicing operation routines for each of the pens may be individually established according to their characterizations which are based upon the ink drops to be fired from each of the pens. The timing of the servicing operations for the selected pens may be predicated upon a selected printmode to thereby substantially comply with a user's expectations of throughput and print quality. In addition, the nozzles of each of the printheads may be grouped according to their condition or health. Those nozzles having a condition that falls below a predetermined threshold value may undergo drop detections more frequently than other nozzles. In this respect, the throughput and the print quality of a printing operation may be adjusted according to user preferences.

Abstract: The amount of time required to perform ink drop detections may be substantially reduced by characterizing which nozzles stand a greater likelihood of failure and by performing drop detections more frequently on those nozzles as compared to nozzles that have been identified as having less of a risk of failure. Continuous drop detection on those nozzles that have been identified as standing less of a risk of failure may be substantially omitted, without negatively impacting the quality of a printed output in a substantial manner. By selectively performing drop detections on those nozzles that stand a greater likelihood of failure, it may be possible to both reduce the amount of time required to test the nozzles as well as substantially any negative impact on print quality caused by these nozzles. The characterization of the nozzles as standing a greater likelihood of failure may be based upon the selected printmode.

Abstract: The amount of time required to perform ink drop detections may be substantially reduced by characterizing which nozzles stand a greater likelihood of failure and by performing drop detections more frequently on those nozzles as compared to nozzles that have been identified as having less of a risk of failure. Continuous drop detection on those nozzles that have been identified as standing less of a risk of failure may be substantially omitted, without negatively impacting the quality of a printed output in a substantial manner. By selectively performing drop detections on those nozzles that stand a greater likelihood of failure, it may be possible to both reduce the amount of time required to test the nozzles as well as substantially any negative impact on print quality caused by these nozzles. The characterization of the nozzles as standing a greater likelihood of failure may be based upon the selected printmode.

Abstract: A method and apparatus for servicing a pen in an inkjet printing device includes receiving a print job, determining a level of print quality required for the print job, detecting the operating characteristics of a number of nozzles to be used to print the print job; and, in the event that the operating characteristics of the nozzles are sufficient to meet the level of print quality, printing the print job. A maintenance procedure may be scheduled in the event that an individual one of the nozzles is not fully functional. In addition, the maintenance procedure may be scheduled to be performed during a time when the inkjet printing device is idle.

Abstract: Computation and data-storage are minimized in both accounting for element condition and reallocation of print tasks away from subnominal elements. An accounting function maintains an element-condition tabulation partly in a cumulative form—representing element stability directly without later interpretation. A reallocation distributes print burden from a subnominal element to plural other elements without making a new mask. Rather, entries for a poor element in a current mask are shifted prospectively and quickly to other elements serving the same pixel rows.

Abstract: The procedure consists of the catalytic thermal decomposition of a carbamate in the presence of natural or synthetic carbamates as catalysts. Isocyanates with high yields and high reaction speeds are formed selectively.