Abstract: A star wheel manufacturing process, and a star wheel manufactured thereby, suitable for an ink jet printer. Metal is formed by chemical milling, subtractive etching or the like, into the desired star wheel configuration, including a plurality of radially extending projections having tips. At least a portion of each tip has an electropolished surface. A coating of fluorinated polymer or the like may be applied to at least a portion of the electrolpolished surface on each tip.

Abstract: The invention relates to an ink level sensing apparatus including an ink cartridge having an ink chamber containing ink and having at least one substantially transparent side panel adjacent the ink chamber. A fluorescent material is disposed in the ink chamber, the fluorescent material being substantially insoluble in the ink and having a specific gravity which is sufficiently lower than the ink to provide an interface between the ink and the fluorescent material. A relatively narrow band light source for emitting light at a first wavelength along a light path through the substantially transparent side panel of the ink cartridge is provided for exciting the fluorescent material. A photosensor for receiving light emitted from a fluorescent material at a second wavelength when the excited fluorescent material crosses the light path is provided, wherein the first and second wavelengths are substantially different.

Abstract: A system and method for allowing a user to program characteristics of at least one light emitting diode (LED) in order to convey information about the operational status of an appliance, such as a printer. The user of the printer selects one of a plurality of display mode options for the LED for a particular operational status condition of the printer. For each display mode option, there is a range of parameters that can be programmed by the user. Display mode setting information for the particular operational status condition (and chosen parameters) is stored based on a selected display mode option. The display mode option may be tested for a particular set of parameters to allow the user to adjust the parameters to his/her liking. Moreover, a combination of display mode options may be programmed for an operational status condition.

Abstract: An ink supply and delivery system for a printer cartridge including a printer cartridge having an interior, at least one air inlet to the interior, and at least one ink outlet from the interior. An air pump is connected to the air inlet of the printer cartridge and creates a positive pressure in the interior of the printer cartridge. The system further includes an ink source, including ink, in the interior of the printer cartridge, the ink source in fluid communication with the ink outlet of the printer cartridge whereby the positive pressure created by the air pump in the interior of printer cartridge forces ink to flow from the ink source in the interior of the printer cartridge through the ink outlet. The ink source is preferably in a resilient container, and the system alternately includes a resilient air container either within, next to, or encapsulating the resilient container of the ink source.

Abstract: A method of performing interlace printing on a print medium with a printhead of an ink jet printer includes providing an array of pixel locations on the print medium. Each pixel location has a common maximum number M of ink drops that the pixel location may receive. Each pixel location is assigned a respective desired number D of ink drops which are to be placed at the pixel location. Each desired number D is less than or equal to M. Sets of threshold values are created. A number N of the sets of threshold values is equal to or greater than M. Each of the pixel locations corresponds to one of the threshold values of each set of threshold values. A respective, single ink drop is selectively jetted at each pixel location. Whether the single ink drop is jetted onto a respective pixel location is dependent upon the desired number D assigned to the respective pixel location and the corresponding threshold value of one of the sets of threshold values.

Abstract: A binary printer for printing halftone color images on a substrate so that the determination of whether to print a dot or to not print a dot of each color ink at each pixel location is based at least in part upon an estimated temperature of the print head. The temperature of the print head may be estimated based upon direct measurement of the ambient temperature and/or direct measurement of temperature of some portion of the print head. Alternatively, the temperature of the print head may be estimated by counting the number of dots fired by the print head.

Abstract: A system and method for controlling a stepper motor wherein the amount of memory space needed to store a phase table is minimized. The stepper motor controller comprises a memory sized to store data representing a plurality of states for current outputs to be supplied to a first winding of a stepper motor and from which are derived current outputs for the first winding and a second winding of the stepper motor. A finite state machine is coupled to the memory. The finite state machine comprises a first address register that stores an address for data in the memory for a present state of the first winding and a second register that stores an address for data in the memory for a present state of the second winding.

Abstract: Mechanical and electrical characteristics of individual print cartridges are determined and used to generate control information for customizing control of each individual print cartridge. One or more characteristics including nozzle heater resistance, drop mass and drop velocity for individual print cartridges are determined and used to derive offset values for widths of pulses used to drive nozzle heaters in the individual print cartridges. While all three characteristics are preferably used, any one or two may also be used. Once determined, pulsewidths or offsets from nominal pulsewidths to improve or optimize printing using the print cartridges are stored in memory devices located on the print cartridges so that printers utilizing the print cartridges can retrieve the pulsewidth or offset data and utilize it in customizing or individualizing control of the print cartridges.