Abstract: Methods and systems for calibrating media indexing errors in a printing device are provided. In one embodiment, the method comprises feeding a calibration media through a printing device, sensing the position of the media as it moves through the printing device, sensing positions of a media indexing component as the media moves through the printing device, determining media indexing position errors based upon the sensed positions, and calculating a compensation factor to be applied based upon the errors. In some embodiments, parameters of a line and/or other function are determined from the error data and the parameters are utilized to calculate a compensation factor. Moreover, in some embodiments, it is determined what range the data fits within, and a predetermined compensation factor is determined based upon the range.

Abstract: A method for calibrating a printhead includes printing a test pattern, scanning the test pattern to obtain calibration data, performing an ink drop velocity optimization for the printhead using the calibration data, and determining a bi-directional offset based on the calibration data.

Abstract: An image sensor has two or three rows of imaging elements, all the imaging elements being of the same size. This provides the rows with a native resolution. The image sensor is also provided with three shift registers. First and second shift register elements receive information from respective corresponding imaging element in a first and second row of imagining elements while shift register elements of the third shift register receive information from four imaging elements. The four imaging elements form a super-pixel, allowing the sensor to output information in a low resolution mode, as well a native and a high resolution mode.

Abstract: A method for determining ink drop velocity of a printhead located at a gap above a print medium. A first ink mark is printed at a first printhead velocity. A second ink mark is printed at a different (in magnitude and/or direction) second printhead velocity. The ink for the second ink mark is ejected from the printhead at the same print ejection position used for the first ink mark plus an offset distance (if any). An optical scan of at least a portion of the print medium is generated using a non-printhead-carrier-mounted optical scanner. The distance between the ink marks is measured using the optical scan. The ink drop velocity is calculated using the measured distance, the offset distance, the first and second printhead velocities, and the gap.

Abstract: An encoder and related methods for use in a printing device indexing system are provided. In some embodiments, the system comprises a feedroller or other component configured to index media through a printing device, and an encoder disk is coupled to the feedroller. In these embodiments, the system includes a reflective optical detector having a transmitter and a receiver provided adjacent a first surface of the encoder disk, the reflective optical detector being configured to detect the passage of the home position mark as the encoder disk rotates by the reflection of radiation off of the first surface. Also provided in some embodiments are methods for setting a counter to correspond with the home position of a rotatable element by utilizing threshold signal levels.

Abstract: A gauge for detecting the level of ink in a printer's ink reservoir includes: a transmitter antenna adapted to be positioned adjacent to an outer surface of a printer's ink reservoir; a transmitter circuit operatively coupled to the transmitter antenna for generating a radio-frequency signal for transmission by the transmitter antenna; a receiver antenna; a receiver circuit for obtaining at least a portion of the radio-frequency signal received by the receiver antenna; and a processing circuit, operatively coupled to the receiver circuit, and configured to determine an approximate level of ink in the ink reservoir based upon, at least in part, a characteristic of the obtained portion of the radio-frequency signal, such as a voltage level of the obtained portion of the radio-frequency signal.

Abstract: In an ink jet printer, a method of selecting an optimized energy level associated with a target ink drop velocity including the acts of: moving a printhead across a print medium at a plurality of scan velocities including a first velocity and a second velocity, printing at least one set of patterns on the print medium by supplying at least one predetermined energy level to at least one actuator of the printhead, the at least one set of patterns including a first pattern printed at the first velocity and a second pattern printed at the second velocity, associating the first pattern with the second pattern and selecting the optimized energy level associated with the target ink drop velocity.

Abstract: In an ink jet printer, a method of selecting an optimized energy level associated with a target ink drop velocity including the acts of: moving a printhead across a print medium at a plurality of scan velocities including a first velocity and a second velocity, printing at least one set of patterns on the print medium by supplying at least one predetermined energy level to at least one actuator of the printhead, the at least one set of patterns including a first pattern printed at the first velocity and a second pattern printed at the second velocity, associating the first pattern with the second pattern and selecting the optimized energy level associated with the target ink drop velocity.

Abstract: Methods and systems for calibrating media indexing errors in a printing device are provided. In one embodiment, the method comprises feeding a calibration media through a printing device, sensing the position of the media as it moves through the printing device, sensing positions of a media indexing component as the media moves through the printing device, determining media indexing position errors based upon the sensed positions, and calculating a compensation factor to be applied based upon the errors. In some embodiments, parameters of a line and/or other function are determined from the error data and the parameters are utilized to calculate a compensation factor. Moreover, in some embodiments, it is determined what range the data fits within, and a predetermined compensation factor is determined based upon the range.

Abstract: An encoder and related methods for use in a printing device indexing system are provided. In some embodiments, the system comprises a feedroller or other component configured to index media through a printing device, and an encoder disk is coupled to the feedroller. In these embodiments, the system includes a reflective optical detector having a transmitter and a receiver provided adjacent a first surface of the encoder disk, the reflective optical detector being configured to detect the passage of the home position mark as the encoder disk rotates by the reflection of radiation off of the first surface. Also provided in some embodiments are methods for setting a counter to correspond with the home position of a rotatable element by utilizing threshold signal levels.

Abstract: A gauge for detecting the level of ink in a printer's ink reservoir includes: a transmitter antenna adapted to be positioned adjacent to an outer surface of a printer's ink reservoir; a transmitter circuit operatively coupled to the transmitter antenna for generating a radio-frequency signal for transmission by the transmitter antenna; a receiver antenna; a receiver circuit for obtaining at least a portion of the radio-frequency signal received by the receiver antenna; and a processing circuit, operatively coupled to the receiver circuit, and configured to determine an approximate level of ink in the ink reservoir based upon, at least in part, a characteristic of the obtained portion of the radio-frequency signal, such as a voltage level of the obtained portion of the radio-frequency signal.

Abstract: A method of optimizing a relationship between fire energy and drop velocity associated with a printhead is provided. A test pattern is printed by selectively supplying energy distribution signals to a plurality of actuators of the printhead. The energy distribution signals have distinct energy profiles. The test pattern is scanned to obtain drop velocity information corresponding to the energy distribution signals. Based on the drop velocity information, an energy profile is determined that optimizes the relationship between fire energy and drop velocity.

Abstract: A method for determining ink drop velocity of a printhead located at a gap above a print medium. A first ink mark is printed at a first printhead velocity. A second ink mark is printed at a different (in magnitude and/or direction) second printhead velocity. The ink for the second ink mark is ejected from the printhead at the same print ejection position used for the first ink mark plus a predetermined offset distance (if any). The distance between the ink marks is measured. The ink drop velocity is calculated using the measured distance, the predetermined offset distance, the first and second printhead velocities, and the predetermined gap. In another method, an ink mark is printed, a distance is measured between the ink mark and the ink-ejection position, and the ink drop velocity is calculated using the measured distance, the printhead velocity, and the gap.

Abstract: A method of imaging substance depletion detection in an imaging device. The method includes the steps of identifying a theoretical coverage of an imaging substance for a first area of a sheet of print media; determining an actual coverage of the imaging substance for the first area of the sheet of print media; comparing the theoretical coverage with the actual coverage; and determining whether a depletion of the imaging substance has occurred based on a result of the comparing step.

Abstract: Changes in the concentration of a chemical, such as a gas, are determined using a non-linear chemical sensor which is subject to shifts in calibration over time. In order to minimize errors caused by such shifts in calibration a first infrared signal (Ig(1)) is measured and using an absorption value under an assumed chemical concentration (C(1)), a zero chemical signal Io(1) is calculated using the known physical law and mathematical relation Absorption=1−Ig/Io. A second infrared signal (Ig(2)) is then measured and the absorption value is calculated using the previously calculated zero chemical signal. A second concentration (C(2)) is then determined and the change in concentration is calculated by subtracting C(2) from C(1).