Abstract: One aspect of the invention lowers boundary artifacts by depleting selectively at a boundary, only in high-color-saturation areas. In another aspect, printmasking defines depletion regions. In yet another, a printer treats different drop-to-pass allocations as of opposite sign. Some preferred embodiments exploit the multilayer Shakes mask system: each mask represents a number of drops to fire, and masks are additive, depending on image content. In preferred embodiments the high-value mask is used in opposition, reducing the number of drops to fire. Bits are set in this mask at pixels close to boundaries, to define depletion regions that negate artifact-causing boundary coalescence. An adaptive version measures nonuniformity in an area-fill test pattern, and uses results to define localized depletion bits for high-value mask(s).

Abstract: One aspect of the invention lowers boundary artifacts by depleting selectively at a boundary, only in high-color-saturation areas. In another aspect, printmasking defines depletion regions. In yet another, a printer treats different drop-to-pass allocations as of opposite sign. Some preferred embodiments exploit the multilayer Shakes mask system: each mask represents a number of drops to fire, and masks are additive, depending on image content. In preferred embodiments the high-value mask is used in opposition, reducing the number of drops to fire. Bits are set in this mask at pixels close to boundaries, to define depletion regions that negate artifact-causing boundary coalescence. An adaptive version measures nonuniformity in an area-fill test pattern, and uses results to define localized depletion bits for high-value mask(s).

Abstract: Techniques for encoding data identifying media type and roll length information on a print media for a large format printer. A method for described for identifying at least a media length value for a roll-type media to be printed upon to a printer controller in a printer. The method includes in one embodiment, keeping track of the length of media used during printing operations, prior to removing the roll from the printer, printing an indicia on a remaining portion of the roll which identifies at least the remaining length of the print medium, removing the roll from the printer, reinstalling the removed roll in the printer, reading the indicia to determine the remaining length of the media, and using the remaining length information during subsequent printing operations. The data can be encoded as a grayscale code which is read by the printer's optical sensor, or be a human-readable indicia.

Abstract: Variances are introduced into at least one component of a large format inkjet printer to substantially reduce the formation of vertical bands during a printing process. In one respect, the relationship between the carriage speed and the vibrations caused by operation of the voltage receiving component is utilized in the implementation of the variances. That is, operation of the voltage receiving component creates a temporal frequency caused by its vibration which leads the carriage to vibrate at a certain rate of time (temporal frequency) as it travels across the printing pass. At least by virtue of the travel across the printing pass, the carriage converts the temporal frequency caused by the vibrations of the carriage and the voltage receiving component into a spatial frequency. The temporal frequency generally translates into a delay or an event that occurs at certain moments in time which may cause drops of ink that are fired to be misplaced on the medium.

Abstract: To avoid the effects of unwanted variations in the pen-to-paper spacing of a printer, deliberate and effectively randomised variations are introduced by using paper drive rollers (20) with an irregular cross-section. In one embodiment, an overdrive roller comprises rollers (23-26) the surfaces of which incorporate flattened portions (27, 28) of differing widths and spacings. The number, size and/or spacing of the portions (27, 28) differ from roller to roller. Instead or in addition, variations may be incorporated into a pinch wheel (101), platen (15) or other component of the paper drive system.

Abstract: Variances are introduced into at least one component of a large format inkjet printer to substantially reduce the formation of vertical bands during a printing process. In one respect, the relationship between the carriage speed and the vibrations caused by operation of the voltage receiving component is utilized in the implementation of the variances. That is, operation of the voltage receiving component creates a temporal frequency caused by its vibration which leads the carriage to vibrate at a certain rate of time (temporal frequency) as it travels across the printing pass. At least by virtue of the travel across the printing pass, the carriage converts the temporal frequency caused by the vibrations of the carriage and the voltage receiving component into a spatial frequency. The temporal frequency generally translates into a delay or an event that occurs at certain moments in time which may cause drops of ink that are fired to be misplaced on the medium.

Abstract: One invention aspect forms a mask and matrix of corresponding backups for values in the mask, checks when a mask value is not working, and replaces only that value with only a matching matrix entry. A second matrix of further backups is best formed. Another aspect forms a mask as a matrix of stacks of matching entries for mask positions; selects an entry for each position from the matching matrix stack; and prints using the selected entry at each position. Another aspect forms a mask as a matrix of stacks of matching entries for mask positions, and rotates each stack to select an entry for each position. Another aspect forms a mask and a matrix of stacks of backups; finds nonworking mask values and replaces such values with backups from a matching stack. Another aspect forms a seminal mask, tiles it to make a larger one with related properties, and injects noise to disrupt tiling-caused regularity and form a less-regular mask.

Abstract: In a method and apparatus, ink tubes are flushed by replacing a plurality of components of an ink delivery system with a plurality of purging components. Purging is controlled In response to the replacement of the components, wherein purging fluid is introduced into the inlet end of a tube in an ink delivery system, a printhead is operated to cause the purging fluid to flow through the tube and be expelled by the printhead, and the purging fluid is collected. Each of the components is provided with identifying information which can be provided to a microprocessor in the apparatus.

Abstract: A structure of bands is associated with printhead-array image-forming elements, forming a printmask. Some band pairs are complementary. A low usage percent is stated for at least one band and a like value for another, a complement to each “at least one” band, to smooth the mask and image. The invention best sets a number N of passes, a wavenumber multiplier M for the image, and overall number B of bands N×M×2, the “2” accounting for odd and even elements; bands appear in order: first group of M bands, odd and even, second group of M bands, odd and even, . . . (N−1)th group of M bands, odd and even, Nth group of M bands, odd and even. In another novel aspect the invention has programming for creating a geometrical structure of bands, respectively associated with the image-forming elements and constituting the printmask.

Abstract: To avoid the effects of unwanted variations in the pen-to-paper spacing of a printer, deliberate and effectively randomised variations are introduced by using paper drive rollers (20) with an irregular cross-section. In one embodiment, an overdrive roller comprises rollers (23-26) the surfaces of which incorporate flattened portions (27, 28) of differing widths and spacings. The number, size and/or spacing of the portions (27, 28) differ from roller to roller. Instead or in addition, variations may be incorporated into a pinch wheel (101), platen (15) or other component of the paper drive system.

Abstract: In various methods, image registration variations among test patterns are used to calibrate misalignment among one or more printheads, paper advance distance, different portions of an inkjet printhead, or bidirectional printhead alignment. A set of test patterns are printed. Each pattern includes a reference portion and a varying portion. The varying portion is changed from pattern to pattern in a manner for testing a parameter being calibrated. An optical sensor scans each test pattern. The parameter setting for the lest pattern having the highest reflectance (i.e., most blank space) is selected as the calibrated parameter value.

Abstract: The present disclosure relates to a replaceable ink cartridge for providing ink to an ink-jet printer. The replaceable ink cartridge includes a memory associated with the replaceable ink container. The memory has a single data terminal and a reference terminal. The memory is responsive to control signals provided to a single data terminal relative to the reference terminal by the ink-jet printer for providing a data signal representative of stored information to the single data terminal relative to the reference terminal. The data signal is sensed by the ink-jet printer for adjusting printer operation.

Abstract: A printer/copier apparatus is adapted to receive a replacement ink cartridge that is employed during the printing/copying operation. The apparatus includes a receptacle with a first connector that is coupled to a processor which controls operation of the apparatus. The cartridge includes a second connector which mates with the first connector and a serial access memory that is connected to the second connector. Data transfers are enabled both from and to the memory to enable access and modification of data stored therein that is indicative of cartridge usage, calibration, and to parameters for controlling operation of the apparatus. The invention is applicable to replaceable apparatus used with laser and ink jet printers, copiers, etc.

Abstract: A printer/copier apparatus is adapted to receive a replacement ink cartridge that is employed during the printing/copying operation. The apparatus includes a receptacle with a first connector that is coupled to a processor which controls operation of the apparatus. The cartridge includes a second connector which mates with the first connector and a serial access memory that is connected to the second connector. Data transfers are enabled both from and to the memory to enable access and modification of data stored therein that is indicative of cartridge usage, calibration, and to parameters for controlling operation of the apparatus. The invention is applicable to replaceable apparatus used with laser and ink jet printers, copiers, etc.