Abstract:
The invented bidirectional graphics printing method includes software which first receives data describing at least part of an image to be printed, and then looks for breaks in the image. When a break is detected, bidirectional printing is allowed if such printing would increase throughput. If no break is detected, the next printhead pass is in the same direction as the previous pass.
Abstract:
An on-page inkjet printhead spitting system purges the printhead nozzles across the printed page, and occasionally in the conventional service station spittoon. In addition to the image-forming droplets, extra purging droplets are fired to maintain pen health. To determine when to purge each nozzle, the number of times each nozzle is fired to print the image is counted or estimated, or printhead characteristics are monitored. The purging dots may be located on the page, in the spittoon, or both. On the page, the purging dots may be hidden from view, in the image background or over the image dots, or hidden in plain sight adjacent image dots, in speed bars, in a watermark type design, or in a repeating pattern. Use of this on-page spitting system conserves ink and improves throughput of the printing mechanism, without requiring any sacrifice in the print quality appearance to the naked eye.
Abstract:
Method and system for increasing the effective resolution at which a lower resolution input pixel image is printed on a higher resolution dot matrix printer such an ink-jet or laser printer are described. Illustratively, a 300-dpi by 300-dpi input pixel image is prepared at the printer for printing at 600-dpi by 600-dpi, with otherwise jagged edges appropriately smoothed to produce high print quality. Each pixel and its predefined neighboring pixels in the input image are compared to stored image templates and when a match is found, the corresponding quad pixel, or super-pixel, to be output is altered from a mere replication of the input pixel, thereby to eliminate jagged edges. Memory space in the printer is reduced by storing templates that represent only a fraction of the problem patterns, the input pixel image being reoriented between comparisons in order to account for all possible cases. If it is determined that there are gray-scaled pixels within the neighborhood surrounding and including a given pixel of the input pixel image, the corresponding super-pixel produced at the output for printing preserves the gray-scale of the original.
Abstract:
Multiple algorithms are applied to expand input image data of a variety of lower resolutions to output image data of a variety of higher resolutions with enhanced text quality, particularly in the black datapath controlling an output device such as an inkjet or laser printer. Enhancement techniques include edge smoothing, bit stripping for large drop weight pens, and drop-weight based ink depletion. Embodiments provide algorithms that convert 600×600 dpi input resolution data to 1200×600 dpi output resolution image data or 300×300 to 600×300 dpi resolution (i.e., asymmetric 2:1 ratio resolution conversion along mutually perpendicular axes), including text edge smoothing, while causing minimal change to gray scaled (halftoned) data within images. The invention applies to other resolutions as well. Some embodiments include unidirectional bitstripping that preserves 1200 dpi edges while applying output pixels at only 600 dpi from 1200 dpi resolution output image data. Some embodiments include drop-weight based depletion to adjust the average ink flux to 32 ng per {fraction (1/600)}th inch cell, thereby preventing excess ink application at high output resolutions, e.g., 1200×600 dpi. In various embodiments, operations are performed in hardware modules and/or performed cooperatively as an integrated process to meet system throughput requirements.
Abstract:
Disclosed is a system in an inkjet printer for determining the amount of a fixer to be applied to a medium. The system comprises a fixer generation circuit where the fixer generation circuit determines an amount of a fixer to be applied to a dot location on a medium based on an amount of ink to be applied to the dot location. A bloom encoder circuit is also disclosed for identifying amounts of fixer to be deposited adjacent to dot locations containing ink.
Abstract:
A passively-multiplexed resistor array has rows and columns of conductors. Resistors span the intersections of the conductors, and one or more selected resistors may be energized by energizing the corresponding row(s) and column(s). However, other, unselected, resistors may also be partially energized. By adding additional rows or columns of "minimizer" resistors, the maximum power in unselected resistors may be reduced. The minimizer resistors are electrically connected in the passively-multiplexed resistor array but do not perform the function of the other resistors in the array.
Abstract:
When black regions are adjacent to color regions, the adjacent black regions are encoded (rendered) at the resolution of the color regions (e.g., 300 dpi) even though the printer has the capability of printing black at a higher resolution (e.g., 600 dpi). To make full use of the 600 dpi resolution of the printer, the black pixels are separated from the color pixels. The 300 dpi resolution black pixel field is converted to a 600 dpi black image field. A window surrounding a selected group of (600 dpi) black/white target pixels is chosen. The pixels in the window are applied to a logic circuit having a plurality of logical conditions. As a result of the logic processing, values of each of the target pixels can be changed to a different pixel value to avoid jagged edges in the printed images, thereby providing a pseudo-600 dpi resolution for the target pixels. The logical operations are performed until all of the pixels have values determined by the logic circuit. The resulting processed pixel field provides a more satisfactory printed image. The window is selected so that the pixel fields can be represented by word-length data groups. Black pixels rendered at the higher resolution are generally unaffected by the logic circuit. Thus, black pixels are rendered at two resolutions but printed at the same resolution.
Abstract:
Multiple algorithms are applied to expand input image data of a variety of lower resolutions to output image data of a variety of higher resolutions with enhanced text quality, particularly in the black datapath controlling an output device such as an inkjet or laser printer. Enhancement techniques include edge smoothing, bit stripping for large drop weight pens, and drop-weight based ink depletion. Embodiments provide algorithms that convert 600×600 dpi input resolution data to 1200×600 dpi output resolution image data or 300×300 to 600×300 dpi resolution (i.e., asymmetric 2:1 ratio resolution conversion along mutually perpendicular axes), including text edge smoothing, while causing minimal change to gray scaled (halftoned) data within images. The techniques can be applied to other resolutions as well. Some embodiments include unidirectional bitstripping that preserves 1200 dpi edges while applying output pixels at only 600 dpi from 1200 dpi resolution output image data. Some embodiments include drop-weight based depletion to adjust the average ink flux to 32 ng per {fraction (1/600)}th inch cell, thereby preventing excess ink application at high output resolutions, e.g., 1200×600 dpi. In various embodiments, operations are performed in hardware modules and/or performed cooperatively as an integrated process to meet system throughput requirements.
Abstract:
A method for multiplying the speed-resolution product of a raster scanning or imaging device such as an inkjet printer, and a resulting pixel image data structure, are disclosed. Illustratively, a 300-dot per inch (dpi) by 600-dpi logical pixel image is mapped to a corresponding, non-overlapping physical dot image, and the printer's inkjets are fired responsive to the dot image to direct generally spherical ink droplets onto paper at 600-dpi resolution grid timing in order effectively to double the horizontal resolution of the printed pixel image, without increasing the firing rate of the print head. In order to accomplish this, and to avoid ink dot overlap, the printable pixel image is thinned before it is printed by a method that leaves no visible horizontal or vertical gaps by selectively turning off pixels within a `black` image that were on and that otherwise would result in ink dot overlap and slower print head speeds were the inkjets cycled at 600-dpi resolution timing. Pixel thinning is performed substantially without adversely affecting pixel image edge definition.
Abstract:
A printed circuit card includes a modified finger contact spanning two finger contact positions on its edge connector to momentarily short correspondingly adjacent receptacle contacts of a mating receptacle connector when the printed circuit card is either plugged into or removed from the mating receptacle connector.