Abstract: The new heater element design has a pit layer which protects the overglaze passivation layer, PSG step region, portions of the Ta layer and dielectric isolation layer and junctions or regions susceptible to the cavitational pressures. Further, the inner walls of the pit layer define the effective heater area and the dopant lines define the actual heater area. In alternative embodiments, the dopant lines define the actual and effective heater areas, and an inner wall and a dopant line define the actual and effective heater areas. Further, when the new heater element designs are incorporated into printheads having full pit channel geometry and open pit channel geometry, the operating lifetime of the printhead is extended because the added protection of the pit layer prevents: 1) passivation damage and cavitational damages of the heater elements; and 2) degradation of heater robustness, hot spot formations and heater failures well into the 109 pulse range.

Abstract: A method of ML-EM image reconstruction is provided for use in connection with a diagnostic imaging apparatus (10) that generates projection data. The method includes collecting projection data, including measured emission projection data. An initial emission map and attenuation map are assumed. The emission map and the attenuation map are iteratively updated. With each iteration, the emission map is recalculated by taking a previous emission map and adjusting it based upon: (i) the measured emission projection data; (ii) a reprojection of the previous emission map which is carried out with a multi-dimensional projection model; and, (iii) a reprojection of the attenuation map. As well, with each iteration, the attenuation map is recalculated by taking a previous attenuation map and adjusting it based upon: (i) the measured emission projection data; and, (ii) a reprojection of the previous emission map which is carried out with the multi-dimensional projection model.

Abstract: A process for precision patterning or cutting of a sheet stock, such as an adhesive tape, includes the step of irradiating a surface of a sheet stock with an irradiation source to pattern or cut a part in the sheet stock. The method is particularly useful for precision cutting adhesive members, such as adhesive fluid seals, for an inkjet print cartridge.

Abstract: The systems and methods of this invention allows for an electrical contact structure of the drop ejecting transducer in an inkjet printhead to be designed in such a way that the relatively thick electrical contact lines are not in the ink drop ejection path between the drop ejector transducer and the corresponding nozzle. Such a design thereby minimizes any visible defects due to misdirected satellite drops.

Abstract: A gamma camera system includes a rotatable gantry supporting multiple detector heads each capable of receiving radiation from a region of interest of a subject disposed in an examination region. Each of the detector heads include a collimator which substantially defines the resolution and sensitivity of the respective detector head. At least two of the detector heads include collimators providing different resolution. Preferably, one of the collimators provides a detector head with substantially high resolution and another provides a detector head with substantially high sensitivity. An operator selectively combines image data detected by each of the multiple detector heads. If desired, the operator combine the image data from the multiple detector heads in a variety of manners to obtain images of various resolution and sensitivity from a single imaging procedure. The operator may also selectively weight the contribution that the image data from each of the detector heads has in the overall image.

Abstract: A drive transistor for a high resolution ink jet printhead having a pocket implant in the gate region of the device. The pocket implant enables a reduced source to drain spacing without loss of breakdown voltage. Accordingly, the size of the transistor may be reduced. Alternatively, this device is suitable for addressing 1200 spi resolution printheads. In one embodiment, the pocket implant extends about 1 .mu.m beyond the gate region towards the drain region. Both embodiments produce a graded drift region.

Abstract: A high voltage MOS transistor, for use in a thermal ink jet printhead, is fabricated with a single, uniformly thick layer of polysilicon that serves as a field plate over the drift region and a gate over the channel region. The fabrication of the drift region and associated drift oxide is performed in a sequence independent of the device channel stop and field oxide fabrication, allowing the drift region to be optimized by varying the thickness of the drift oxide. Using a field plate to increase the breakdown voltage of the device by reducing the concentration of the electric field, the device transconductance is increased by increasing the doping of the drift region without an attendant decrease in breakdown voltage.

Abstract: An ink jet printhead is disclosed which has improved printhead cooling thereby improving operating efficiency. The printhead is constructed so that the manifold bringing ink from an ink reservoir into an ink inlet to the printer directly contacts the thermally conductive surface of the substrate in which the heater elements are formed- The cooler ink removes some of the accumulated heat from the heater substrate and is subsequently ejected. In one embodiment the printhead comprises an upper channel substrate which is bonded to a lower heater substrate which is formed with a ledge which extends past the rear face of the channel substrate. The channel substrate has an ink inlet formed into its rear face and adjacent to an extended portion of the heater silicon surface. An ink reservoir brings ink to the printhead via an ink manifold which is sealed against the exposed silicon surface and against the side of the ink inlet.

Abstract: A method of resampling of a sinogram from a fan beam SPECT includes the steps of angular resampling of the sinogram using frequency modulation, and thence transfers resampling of the sinogram using linear interpolation. This permits the use of parallel geometry algorithms in quantitative work without the expected degradation of resolution or the introduction of artifacts.

Abstract: A method for electrical tailoring of thermal ink jet heater elements. The resistance of ink-jet heater elements formed of polysilicon is changed by applying energy through the resistor element of varying amounts at varying pulse widths. The application of pulsed current for up to 1 second total pulse width at voltages of up to 50 volts decreases the resistance by as much as thirty percent or more of the as fabricated values.

Abstract: An ink-jet printhead fabrication technique enables capillary channels for liquid ink to be formed with square or rectangular cross-sections. A sacrificial layer is placed over the main surface of a silicon chip, the sacrificial layer being patterned in the form of the void formed by the desired ink channels. A permanent layer, comprising permanent material, is applied over the sacrificial layer, and, after polishing the two layers to form a uniform surface, the sacrificial layer is removed. Preferred materials for the sacrificial layer include polyimide while preferred materials for the permanent layer include polyarylene ether, although a variety of material combinations are possible.

Abstract: An ink jet printer is configured in a hybrid architecture wherein a full width printbar is combined with a partial width color scanning assembly to provide the capability of selectively printing in black only or, alternately, of producing color prints by operating the color scan assembly exclusively. The cost of the hybrid system, when compared to a full width color system using four full width printbars, is greatly reduced. Throughput time is reduced by providing the control circuitry for distinguishing between black only and color operation and selectively controlling the printer mode of operation. The hybrid architecture is particularly useful in a LAN system since it provides a mechanism for balancing the relative color versus black page decomposition speed limitations. Also, the hybrid architecture enables a relatively simple implementation of a checkerboarding technique to suppress banding in output prints.

Abstract: An improved microelectromechanical device, such as a thermal ink jet die or printhead, is formed by the alignment of two planar substrates bonded together by an intermediate thick film layer of patterned polymeric material, such as polyimide. The improved device has a fully cured, patterned thick film layer which is planarized by chemical-mechanical polishing-to improve the bonding strength between the substrates. The planarization removes topographical formations generated during the deposition of the thick film layer and/or during the patterning of the recesses therein.

Abstract: An ink jet module that can be accurately positioned on a carrier includes a channel die and a heater die. The channel die is rectangular and has a top surface, a bottom surface, a first pair of sides, and a second pair of sides. The bottom surface has a number of spaced parallel channels disposed within it. The channels are parallel to the first pair of sides and extend through one of the second pair of sides. The top surface of the heater die is attached to and aligned with the bottom surface of the channel die. At least one pair of alignment features is disposed within and adjacent a side of the bottom surface of the channel die. The alignment features are recessed areas disposed on opposite sides from each other. The alignment features are dimensioned to receive a retainer that secures the ink jet module to a carrier.

Abstract: An electrostatic discharge protection device for a connector associated with an integrated circuit chip, particularly one associated with a thermal ink-jet printhead. AMOS field effect device extends along at least one edge of the connector on the chip. A bipolar transistor, parasitic to the field effect device, conducts current from the connector to ground in response to a voltage between the connector and ground in excess of a predetermined threshold. A zone of a predetermined electrical resistance is operatively disposed between the bipolar transistor and ground. The zone may substantially encircle the bonding pad of the connector to evenly distribute local incidences of high voltage. The invention enables integrated circuits to pass ESD requirements of office products, which is 15 kV by Human Body Model testing.

Abstract: A wide semiconductor transducer device comprises a linear array of semiconductor chips. Each of the semiconductor chips has a plurality of transducer elements arranged on it along a front edge at a constant spacing, the constant spacing being maintained across the semiconductor chip boundaries. Each of the semiconductor chips also includes associated transducer circuits which are each connected one of the plurality of transducer elements formed on the semiconductor chip. While the requirement that the transducer elements maintain the constant spacing requires them to be located within a damage zone created during the dicing and/or thermally induced compression of the semiconductor chip, the associated transducer circuits can be located within an interior portion of the semiconductor chip. The interior portion of the semiconductor chip is located a sufficient distance from the edges of the semiconductor chip such that it does not encroach on the damage zone.

Abstract: An electrostatic discharge protection device for a connector associated with an integrated circuit chip, particularly one associated with a thermal ink-jet printhead. A MOS field effect device extends along at least one edge of the connector on the chip. A bipolar transistor, parasitic to the field effect device, conducts current from the connector to ground in response to a voltage between the connector and ground in excess of a predetermined threshold. A zone of a predetermined electrical resistance is operatively disposed between the bipolar transistor and ground. The zone may substantially encircle the bonding pad of the connector to evenly distribute local incidences of high voltage. The invention enables integrated circuits to pass ESD requirements of office products, which is 15 kV by Human Body Model testing.

Abstract: A thermal ink jet printhead includes a switched power supply for the intermediate voltage predriver sections. The power supply is switched by a MOSFET connected between an intermediate point of a voltage divider and ground. By switching the power supply, the predriver sections are turned off, unnecessary power consumption and overheating the printhead are avoided.

Abstract: An electrostatic discharge (ESD) protection device for protecting a high voltage operating circuit having a high voltage input terminal is disclosed. The ESD protection circuit has a substrate, a first diffusion region formed in the substrate connected to the high voltage input terminal, a second diffusion region formed in the substrate connected to ground, a field oxide layer over the substrate having a thickened region extending into the substrate between the first and second diffusion regions, and a drift region formed in the substrate and located between the first diffusion region and the thickened field oxide layer. These regions are so arranged to move the point of avalanche breakdown away from the first diffusion/field oxide interface, so that the avalanche breakdown voltage is lower than that of the protected circuit while simultaneously preventing avalanche included bipolar feedback in the protection device.

Abstract: A controller controls an ink jet printing apparatus that propels ink jet droplets on demand from a printhead having a plurality of drop ejectors. The printhead includes a plurality of heater elements which are responsive to electrical input signals, each input signal having an amplitude and time duration which produce a temporary vapor bubble and cause a quantity of ink to be ejected for creation of a mark on a copy sheet. The controller has power supply means and delay means that vary the amplitude and duration of the input signals in relation to the printhead temperature.