Abstract: A printing method and printing apparatus capable of printing a high-quality image representing excellent tonality even when a plurality of inks having the same color and different densities are adhered to the substantially same pixel position on a printing medium to form one print dot and represent tonality. When printing is to be performed on a printing medium by discharging ink from an inkjet printhead using a plurality of inks having different densities, this apparatus calculates a lapse time from previous ink discharge, predicts a density change according to the lapse time based on the calculated lapse time, selects an ink and ink discharge amount suitable for representing a density value indicated by input multi-valued image data based on the predicted density change of ink, and drives the printhead so as to cause ink discharge from the printhead based on the selected ink and ink discharge amount.

Abstract: When a print nozzle or other firing element of an ink jet print head fails, printed image quality suffers. In a print head where there are additional printing elements that continue to work and that are adjacent the failed element, a failed firing element can be compensated for by increasing the firing rate of, or firing pulse duration to, one or more printing elements that are adjacent to the failed element. Additional ink deposited on the printing medium will bleed onto areas that are normally printed onto by the failed firing element.

Abstract: An apparatus for determining the time at which a charged droplet is at a predetermined physical position comprising: first and second electrodes (1, 3) past which said droplet passes in use of said apparatus, said droplet inducing a charge on each said electrode (1, 3) as it passes; and circuitry (5, 7, 9) responsive to the charges induced on the first and second electrodes (1, 3) for determining the time at which said droplet is at said predetermined physical position midway between said electrodes (1, 3).

Abstract: The present invention is embodied in a system and method for automatically calibrating the print contrast of an inkjet printing system using an optical-electronic sensor to detect an ink drop volume. The print contrast calibration system includes an optical-electronic sensor that obtains test pattern data from a printed test pattern, a calibration module that contains calibration data for the printing system, an installation module that determines a drop volume score by using the test pattern data and the calibration data and a printing module that determines a print contrast setting based on the drop volume score. The present invention also includes a method for calibrating print contrast in a printing system by storing standard calibration curves for the printing system, comparing the standard calibration curves with a printhead assembly calibration curve to determine a drop volume score, and setting the print contrast based on the drop volume score.

Abstract: Data in memory means of an ink cartridge can be read, written and rewritten by a recording apparatus. When abnormality has occurred in the recording apparatus, the information can be notified to a user or the like based on the data stored in the memory means of the ink cartridge. Further, control means is provided, which reads, writes and rewrites the data stored in the memory means of the ink cartridge, and in case that abnormality such as print error has occurred in the recording apparatus, the information can be given to the user based on the data stored in the memory means of the ink cartridge.

Abstract: An ink cartridge of a printer includes first and second electrodes on opposite sides of an ink reservoir. Level of ink in the reservoir may be measured by applying a sense signal to the first electrode, detecting a signal at the second electrode, extracting DC content of the detected signal, and using the DC content to determine the ink level.

Abstract: In a method for determining the number of normal imprints implementable in a printing device with a remaining ink quantity, to a computational determination of this number is made when a sensor-acquired, predetermined remaining ink quantity is signaled. In an arrangement for the implementation of the method, a microprocessor is programmed to undertake a rough computational determination of the remaining number of imprints to signal the need to change the ink tank cassette before the reserve quantity is tapped for use, to generate a message after a recognition of the change of the ink tank cassette, and to display it on a display. The microprocessor waits for an entry of a code via an input unit. Upon entry of the code, the microprocessor implements a check of the input code as to whether the changed ink tank cassette is authorized, and modifies the operation of the device if the completed check of the code has yielded an invalidity.

Abstract: In an ink jet printer with a print head having two nozzle rows arranged at different positions in a main scanning direction, that is, a 0th nozzle row and a 1st nozzle row, with regard to each color ink, common driving waveforms are used to drive both the 0th nozzle row and the 1st nozzle row. The driving waveforms are periodically and successively output in a specific cycle where a plurality of driving waveforms are allocated to each pixel. A specific relation between the driving waveforms and a pixel is regulated individually for the respective nozzle rows using two latch signals. For example, in the case of nozzles included in the 0th nozzle row, dots are created in a certain pixel with driving signals S1 through S4. In the case of nozzles included in the 1st nozzle row, on the other hand, dots are created in a certain pixel with driving signals S3 through S6.

Abstract: A system of classifying incoming media entering an inkjet or other printing mechanism is provided to identify the media without requiring any special manufacturer markings. The incoming media is optically scanned using a blue-violet light to obtain both diffuse and specular reflectance data, from which a media signature is generated. The generated signature is compared with known signatures for different media types to classify the incoming media, and a corresponding print mode is selected. Finally, the selected print mode for the classified incoming media is stored for future reference. Thus, a consumer can teach the printing mechanism to recognize new types of media. For borderline media falling between two categories, the printer remembers which category was selected previously, and then applies the same print mode to the next borderline media to provide a visually consistent output. A printing mechanism constructed to implement this method is also provided.

Abstract: A method and apparatus for controlling the volume of ink droplets ejected from printhead nozzles over a larger printhead operating temperature range. Each nucleating electrical pulse applied to the heating elements in the printhead to eject an ink droplet is preceded by a plurality of non-nucleating pre-pulses. Based upon the printhead temperature sensed, a controller selects the pre-pulse width and time width between pre-pulses from a look-up table.

Abstract: Printer performs accurate ink-discharge status detection, dependent upon the type of a printhead attached to the printer, the print mode and the color of ink change, and a facsimile apparatus using the printer. Each time printing based on received facsimile image data for one page of print sheet has been completed, the printhead is moved to a position close to a photosensor, and test ink discharge is performed. At this time, the type of printhead is determined, and whether or not the color printhead is in normally-dischargeable status is judged by comparing a pulsewidth obtained from output from the photosensor with a threshold value selected in accordance with the discrimination result. Otherwise, one of a plurality of threshold values according to print modes and ink colors is read from a ROM, and test ink discharge is performed with respect to corresponding color ink. The result of the discharge is compared with the threshold value.

Abstract: For top-of-form calibration of a printer in which a printing medium is fed into a printing position, a predefined pattern is printed so that a print is generated on the print medium. After the print is detected, a feature of the print is determined. The feature is indicative of the printing position. By using a correction factor, which is determined from the feature, the calibration is performed.

Abstract: An ink jet head cartridge includes a recording head for ejecting ink; an ink container for containing the ink to be supplied to the recording head; an air venting opening for communication between the container and ambience to allow supply of the ink from the container to the recording head; wherein the air venting opening is constituted by an outside opening and an inside opening and a passage connecting them, the passage has a length larger than a thickness of the ink container.

Abstract: An image processing apparatus which includes an image signal input device for outputting a first image signal including at least three signals corresponding to cyan, magenta and yellow, respectively, an image signal converter for converting at least one of the signals included in the first image signal into N (N is an integer greater than one) second image signals corresponding to N inks of different concentrations of a same color family, a black abstraction device for performing black abstraction on each of N second image signals individually to produce a third signal, and a signal processor for performing a UCR processing and black inking processing on the second and third signals to produce fourth signals.

Abstract: A low ink sensing system is combined with an ink cartridge detection system to enable a more efficient ink jet printer. An ink container which supplies ink to an associated printhead is modified by the incorporation of two light directing elements, in the preferred embodiment, a faceted prism and a roof mirror, into a transparent wall of the container housing. The cartridge, comprising the ink container and associated printhead, is mounted on a scan carriage. Periodically, the carriage is conveyed to a sensing station comprising a pair of light sources and a commonly used photosensor. A first light source is energized and a beam of light is directed to a location where the roof mirror, would be positioned if the cartridge is present. If the cartridge is absent, lack of a reflected return signal is sensed, indicating a cartridge has not been inserted. Print operation is halted until a cartridge is inserted.

Abstract: A printing head has a plurality of heater boards, each of which includes a shift register to which printing data and selection data for selecting preheating pulse signals are applied as inputs, a latch circuit for latching the printing data, a selection-data latch circuit for latching the selection data, a selection circuit for selecting any one of a plurality of preheating pulse signals inputted in accordance with the latched selection data, and a plurality of heating resistors driven by the printing data or preheating pulse signals. Correction data, obtained by a head correcting apparatus, for performing printing at an average density by correcting the characteristics of each heater board is stored in a memory of the printing head. A printing apparatus decides the selection data in accordance with the correction data and sets the selection data in the selection-data latch circuit.

Abstract: An ink-jet apparatus employs a platen having an array of vacuum ports that are each filtered. The filter is constructed to provide restricted-airflow rates which remain uniform when the platen is either fully covered or partially uncovered. The filter mechanism provides both airflow restrictions such that ink drop flight trajectories in the printing zone are unaffected, acoustic dampening of the vacuum pump is provided, and vacuum pressure is kept relatively high proximate the print media edges.

Abstract: An ink smearing preventing method of terminal equipment of inkjet output device resolves the drawback of the ink smearing which is caused due to ejection prior to ink drying during data printing onto paper, for which the ink smearing preventing method is provided to a printing manner where the next line is systematically printed regardless of the amount of ink sprayed, to adjust the printing speed such that the paper is ejected after the sprayed ink dries, by regulating the printing time of the next line according to the amount of ink, after determining the amount of ink sprayed.

Abstract: In a control method for an ink jet recording apparatus with which an amount of head generated by the head is restricted when a condition of a head temperature being not lower than a predetermined threshold is found includes the steps of detecting the head temperature and an environment temperature around the head, and restricting an extent of the amount of head generated by the head depending on the environment temperature or a difference between the head temperature and the environment temperature.

Abstract: A method of pretreating an ink-jet printer (10) before it is used is provided, wherein the printer includes a printing head (16) provided with a plurality of nozzles (28) for ejecting ink-droplets and movable in a reciprocating manner, an ink storage section (40) and an ink supply conduit (42) connecting the printing head with the ink storage section. The entirety of an ink flow passage including the ink supply conduit (42) is filled with a colored liquid material (78) having a function for maintaining the hydrophilic nature of the ink flow passage, before the ink-jet printer is forwarded from a factory. Then, before the ink-jet printer is assigned to the user, a printing operation is carried out by the printing head (16) by using the colored liquid material (78) and a character printed with the colored liquid material is observed to determine a printing function.