Abstract: A sensing system is described for detecting the presence of ink at a predetermined level in an ink reservoir for an ink jet printer. The reservoir includes a perimetric wall having first and second wall sections, wherein at least a portion of said first wall section and a portion of the second wall section are substantially transmissive to light. A light emitter is located proximate to the first wall section and positioned at the predetermined level. A photo detector is positioned at the predetermined level and located proximate to the second wall section for detecting the light emitted from the light emitter, the light emitter being oriented to direct light at the photodetector. The light from the light emitter follows a first path when ink is present in the reservoir at the predetermined level and follows a second path when ink is not present in the reservoir at the predetermined level, the photodetector receiving the light from the light emitter traveling only one of the first path or the second path.

Abstract: A color inkjet printer and method of printing includes a printer carriage supported for bi-directional movement along a print swath axis. Color inkjet printheads of different colors are mounted for movement with the carriage. The printheads are mounted in only two rows which are directed along the print swath axis. One row of the two rows of printheads is formed of printheads for printing a first primary color and a printhead for printing black. Another row of the two rows of printheads is formed of printheads for printing a second primary color and a printhead for printing yellow. Nozzle arrays of printheads for printing the first primary color and the nozzle array of the printhead for printing black do not overlap in the direction along the print swath axis with the nozzle arrays of printheads for printing the second primary color and the nozzle array of the printhead for printing yellow.

Abstract: A printhead cartridge for use with an ink jet printer is disclosed. The printhead cartridge includes a memory element for storing jet characteristics of the cartridge. These characteristics can be measured during fabrication, upon installation into the printer, or during the operation of the printer. The printer adjusts printing parameters to compensate for the out of specification characteristics for optimized image quality. The compensation is done through adjusting drop ejection energy, thermal control, or replacing failed jets with substitute jets in the printhead. Alternatively, the printer accesses the measured characteristics to determine if they are within specification. If the printhead cartridge does not meet specifications, the user is instructed to remove the printhead cartridge since its use may adversely affect the quality of the resulting image. The printer accesses the measured characteristics throughout the life of the cartridge to ensure the quality of the resulting image does not degrade.

Abstract: A printhead cartridge for use with an ink jet printer is disclosed. The printhead cartridge includes a memory element for storing jet characteristics of the cartridge. These characteristics can be measured during fabrication, upon installation into the printer, or during the operation of the printer. The printer adjusts printing parameters to compensate for the out of specification characteristics for optimized image quality. The compensation is done through adjusting drop ejection energy, thermal control, or replacing failed jets with substitute jets in the printhead. Alternatively, the printer accesses the measured characteristics to determine if they are within specification. If the printhead cartridge does not meet specifications, the user is instructed to remove the printhead cartridge since its use may adversely affect the quality of the resulting image. The printer accesses the measured characteristics throughout the life of the cartridge to ensure the quality of the resulting image does not degrade.