Abstract: An ink stick shape for use in a printer ink stick feed chute is disclosed wherein the opposing sides of the ink stick are tapered or angled from the horizontal so that at least one area intermediate the top and the bottom of the ink stick is a greater distance from the horizontal than the junction of the side walls and the bottom of the ink stick. The ink stick shape or geometry may be keyed to a particular color.

Abstract: The present invention preferably employs a phase change ink composition that includes a combination of different dye types such as an anthraquinone dye and a xanthene dye, which is most preferably a rhodamine dye. While each dye type is insufficiently soluble with respect to favored carrier compositions to preserve color saturation in reduced ink quantity prints, the dye type combination permits increased dye loading and maintains print quality. In a preferred embodiment of the invention, a favored carrier composition is adjusted to promote the colored form of a preferred rhodamine dye (C.I. Solvent Red 49) and mixed with a preferred anthraquinone dye (C.I. Solvent Red 172) whose concentration is kept below a critical level to prevent post printed blooming. The resulting preferred phase change ink compositions provide a magenta phase change ink with enhanced light fastness and color saturation, as well as good compatibility with preferred existing subtractive primary color phase change inks.

Abstract: A phase locked loop (PLL) chain for locking audio sampling to serial digital component video timing has a deserializer that recovers a video sample clock signal from a serial digital video signal, the deserializer including a wide bandwidth PLL. A tracking filter in the form of a narrow bandwidth PLL having a low pass filter function reduces the jitter in the video sample clock signal to produce a stable reference clock signal. The stable reference clock signal is input to an audio sample clock generator to produce a stable audio sample clock signal for extracting audio data from the serial digital video signal.

Abstract: A phase-change ink transfer printing process and apparatus (10) applies a thin layer of a liquid forming an intermediate transfer surface (12) to a heated receiving surface, such as a drum (14). Then an ink-jet printhead (11) deposits a molten ink image (26) onto the heated drum where it cools to the drum temperature and solidifies. After the image is deposited, a print medium (21) is heated by a preheater (27) to a predetermined temperature and fed into a nip (22) formed between the heated drum and an elastomeric transfer roller (23) that is biased toward the drum to form a nip pressure that is about twice the yield strength of the ink image. As the drum turns, the heated print medium is pulled through the nip to transfer and fuse the ink image to the print medium. When in the nip, heat from the drum and print medium combine to heat the ink in accordance with a process window (90), making the ink sufficiently soft and tacky to adhere to the print medium but not to the drum.

Abstract: A method of normalizing performance of an image forming marking element, the method comprising the steps of operating the marking element with an adjustable operating parameter set to a first test value and quantifying a first value of a quantifiable performance characteristic of the marking element, operating the marking element with the operating parameter set to a second test value and quantifying a second value of the quantifiable performance characteristic, calculating an optimum value of the operating parameter, and adjusting the operating parameter to its calculated optimum value.

Abstract: A configurable video sequence viewing and recording system stores multiple computer generated images of a sequence in a frame buffer and plays back the images for animation motion study. The images are stored either in a full size format or in a decimated format according to a decimation factor. The images are read out in real time for display from the frame buffer, with pixels/lines/frames being replicated to provide full size images for a desired number of frames each. The number of images of a sequence to be displayed/stored are determined by an operator, and a loop function is provided so that the sequence may be continuously displayed.

Abstract: A CCD gate driver circuit provides an output drive signal in response to an input clock signal. The output drive signal is symmetrical, uses a minimum amount of power at high frequencies, and compensates for cross-coupling between CCD gates. An input circuit receives the input clock signal and converts it to current pulses on the transitions of the input clock signal. The current pulses are applied to a common input of a pair of complementary input transistors to switch conduction of the transistors. The control inputs of the input transistors are coupled to a reference voltage level. The outputs of the input transistors are coupled to respective current mirrors. The outputs of the current mirrors are in turn coupled to respective inputs of a pair of complementary output transistors that have a common output. A pair of voltage rails that define the voltage swing of the output drive signal are coupled to the respective control inputs of the output transistors.

Abstract: An ink jet (10) apparatus and method provides high-resolution gray scale printing by providing multiple PZT drive waveforms (100, 110, 120), each having a spectral energy distribution that excites a different modal resonance of ink in an ink jet print head orifice (14). By selecting the particular drive waveform that concentrates spectral energy at frequencies associated with a desired oscillation mode and that suppresses energy at the other oscillation modes, an ink drop (170, 180, 190) is ejected that has a diameter proportional to a center excursion size of the selected meniscus surface oscillation mode. The center excursion size of high order oscillation modes is substantially smaller than the orifice diameter, thereby causing ejection of ink drops smaller than the orifice diameter. Conventional orifice manufacturing techniques may be used because a specific orifice diameter is not required.

Abstract: A current probe comprising a Hall device and a secondary winding in a flux linking relationship with a magnetic circuit is self-calibrated by disconnecting the Hall device from the winding, passing a current through the winding so as to induce a magnetic flux in the magnetic circuit, measuring voltage developed by the Hall device in response to linking by the magnetic flux, calculating the Hall gain of the Hall device, and then adjusting the gain of a scaling output amplifier on the basis of the calculated Hall gain to compensate for variation in Hall gain due to changes in operating conditions.

Abstract: A spectrum analyzer (50) has a tunable trigger acquisition system (52) that includes a selectable trigger acquisition bandwidth. Sufficiently wide signal acquisition bandwidth is obtained by tapping into a high-frequency IF amplifier (54) signal and down-converting it to a moderate IF frequency for trigger extraction. A down-conversion local oscillator (62) is phase-lock-loop (64) tunable over a range of the high IF frequencies to allow extracting a time and frequency selectable trigger from the desired carrier signal frequency even if the spectrum analyzer is substantially offset in frequency from the desired carrier. The moderate frequency IF amplifier (66) includes a switchable bandpass filter (68) that provides adequate selectivity to detect triggers from a variety of signal types while rejecting unwanted signals such as adjacent channel CATV carriers that are often detectable when the measurement frequency is offset toward the channel edges.

Abstract: A wide dynamic range optical receiver has low and high sensitivity signal channels for converting first and second portions of an optical input signal into voltage values representative of the various portions of the optical input signal. The voltage signals are converted into digital values by a converting means and a reconstruction is performed in a combining means to produce a digital output representative of the optical input signal. The wide dynamic range optical receiver may be used in an optical signal measurement instrument, such as an optical time domain reflectometer, where the optical return signal from a fiber under test is coupled to the wide dynamic range optical receiver in first and second portions with the first portion having an optical power level substantially less than the second portion.

Abstract: A time-interleaved method for efficient operation of an acoustic wave sensor array couples each sensor repetitively and one at a time via a digitally-addressable analog switch, or multiplexer, to a single oscillator driver to form an oscillation circuit. A frequency of oscillation for each acoustic wave sensor is determined. The frequency for each acoustic wave sensor then is converted into a measurement value for the parameter to which each acoustic wave sensor is sensitive.

Abstract: An internal ink filter (12) located within an ink jet print head (10) is formed by overlapping filter portions (100 and 102) of two laminated plates (22 and 24) that comprise the print head. Each plate includes an array of holes (120) in the filter portion. The individual holes have an opening dimension (122) such that the plates can be easily manufactured using conventional techniques, although the opening dimension may be too large for effective filtering. The plates are juxtaposed with the holes of each plate partly overlapping the holes of the other plate. The areas of overlap define a filter pore smaller than the individual holes in each plate.

Abstract: A print head (216) positioner (260) includes a stepper motor (264) that is coupled by a substantially friction- and backlash-free taut metal band (266) to a lever arm (268) that imparts precise lateral motion to a positioning shaft (220) that is rigidly attached to the print head assembly. Each step of the stepper motor is translated by the lever arm into one pixel (0.085 millimeter) of lateral movement of the shaft. The exact amount of translation per step of the stepper motor is adjustable by an eccentrically mounted ball (272) that is minutely positionable (274) on the lever arm. The ball couples angular motion of the lever arm to lateral motion of the shaft such that adjusting the ball position on the lever arm provides a-variable scale factor adjustment that compensates for tolerance buildups and exact inter-nozzle spacing on the print head. The shaft is biased toward the ball by a spring (284).

Abstract: A return-loss detector for a serial digital signal source uses a return-loss bridge circuit to exploit the broadband spectral characteristics of a serial digital signal from the signal source to monitor the termination conditions of a system being driven. A differential pair of serial digital signals from the source are input to the bridge circuit having a reference termination in one leg and the system termination in the other. A broadband detector is used at the output of the bridge circuit to generate an error signal, which is measured by a detector or metering circuit. The measured signal may be displayed as a value in dB or may be input to a comparator to provide an alarm or warning signal to an operator.

Abstract: A repeatable finite anti infinite impulse response integrated circuit structure has a plurality of filter units programmably interconnected, with each filter unit having a pair of repeatable cells. Each cell has a coefficient stage for receiving a filter coefficient, a mixer stage for multiplying a selected one of a plurality of input signals by the filter coefficient, an accumulator stage for selectively delaying an input accumulation signal, and a summation stage for adding the input accumulation signal to the weighted signal to produce an output accumulation signal. With appropriate programming many desired finite/infinite impulse response filter configurations may be achieved.

Abstract: A digital audio waveform display is presented on a digital video waveform display instrument using the video waveform display circuitry. A decoder extracts embedded digital audio data from a digital video signal. The digital audio data is stored in a buffer memory. N digital audio data words, corresponding to N samples of the video data representing a video line for display, are read from the buffer memory at a video sample rate and input to the video waveform display circuitry. The video waveform display circuitry includes a digital to analog converter operating at the video sample rate and an analog video reconstruction filter which provides amplitude values for a swept display device.