Abstract: The present invention is directed to a compound bore nozzle plate for a thermal ink jet printhead and is manufactured by electroforming nickel onto a nickel substrate which has been masked by a plurality of mask segments of predefined geometry. This geometry consists of a plurality of base segments upon which have been formed a corresponding plurality of post segments of greater vertical dimension and smaller lateral dimension than the base segments. This mask geometry enables greater center-to-center orifice spacing to be achieved without unacceptably reducing the thickness and structural integrity of the nozzle plate.

Abstract: A process for increasing the solubility of carbon black in desired solvents is provided. The process comprises (a) forming a suspension of the carbon black in a non-reactive medium, such as an aromatic hydrocarbon, (b) adding a silylating agent, such as an organosilane, (c) removing the reaction product of the silating agent and the carbon black, and (d) forming a dispersion of the reaction product in a solvent for use as an ink-jet printing fluid.The increased dispersibility of the carbon black of the invention results in a more non-settling suspension of the carbon black "molecules" than otherwise obtained.

Abstract: This method and apparatus for eliminating apparent offset in the servo code adjacent to a guard band on a magnetic memory disc utilizes at least two phases of servo code per magnetic cell for seeking and track centering, or track following, operations and two phases or guard band code per magnetic cell. The two phases or guard band code are each either in phase or similarly out of phase with the respective phases of the servo code in individual magnetic cells.Phase locking on a selected phase of guard band code is achieved by providing a synchronizing code in the guard band using an irregular pattern of guard band code, providing a timing signal count representing a cell count, for example, decoding the synchronizing code to provide an end of code signal and utilizing the end of code signal and a predetermined cell count signal to achieve phase locking on the correct phase of the guard band code.

Abstract: This application discloses a new and improved thermal ink jet printhead and method of manufacture wherein a tape automated bond (TAB) flexible circuit is sequentially thermosonically bonded in a one-by-one wire bonding process to aligned conductive traces on a thin film resistor substrate. These traces provide electrical current paths for a corresponding plurality of heater resistors on the substrate, and these resistors function to heat a corresponding plurality of ink reservoirs in a thermal ink jet printhead.

Abstract: Apparatus and method for testing and determining the operating status of a plurality of ink-ejecting nozzles in a thermal ink jet array. An electrically conductive plate is placed adjacent the ink-ejecting orifices in a test position. An ink droplet appearing from an orifice will, for some brief moment, be in contact with both the orifice plate and the electrically conductive plate. The droplet completes a circuit with a conduction detector and allows current to flow thereby indicating an operative nozzle.

Abstract: An orifice plate for an ink jet printhead wherein a plurality of elongated isolator slots are adjacent the orifices and in fluid communication therewith, so as to prevent cross-talk between adjacent orifices.

Abstract: Cleaning and priming of ink-ejecting nozzles is achieved by engaging the nozzles with an elastomeric suction cup as the printhead moves to the beginning or ending of a print line. The suction cup contains an inner cup of foam which wipes off any residual ink droplets. The cup assembly is connected to a vacuum pump for drawing ink out of the nozzles. The assembly is mounted on a four-bar linkage which, as it rotates, lifts the cup assembly to engage the nozzles in the printhead.

Abstract: A method of providing electrical connections to a flexible circuit member having electrical contact pads of solderable material on one side. The contact pads and the flexible circuit are pierced with contact pins. Solder is caused to flow along the contact pins through the openings in the flexible circuit from the side opposite to that on which the contacts are disposed.

Abstract: A ball is formed at the tip of a wire by an arc. The arc is initiated and maintained across an air gap between the wire tip and an electrode by applying timed RF and DC voltages between them.

Abstract: A quartz crystal oscillator is controlled entirely by digital elements to phase lock with a reference square wavetrain by alternately switching the tuning circuit of the oscillator between first and second configurations. The ratio of the times during which the tuning circuit is in its respective configurations is a function of the relative phases of the oscillator output and the reference wavetrain and serves to determine the precise frequency of the oscillator so as to keep its output locked to the phase of the reference wavetrain.

Abstract: A rear illuminated radiation detector comprising a rear contact adjacent to a substrate substantially transparent to incident radiation of a given frequency range, detector and blocking layers overlying said rear contact, and a front contact overlying the detector and blocking layers. The layers are disposed so that, through them, the front contact is in electrical contact with the rear contact. Radiation may enter the detector layer from the rear, through the substrate, thereby permitting the detector to be operated in a backside illuminated mode. Such detectors may be fabricated in highly dense arrays and coupled to either hybrid or monolithic readout structures as required for operation as a focal plane array radiation detector. Optionally, the front contact may be left exposed so that radiation may enter the detector layer from the front of the radiation detector, thereby permitting it to be operated in both backside and frontside illuminated modes.

Abstract: Apparatus (20) provides a stable optical reference in the presence of optical source jitter. It comprises a beamsplitter cube (21) having an input surface 22, an output surface 23, a totally reflecting surface (24), and a partially reflecting diagonal surface (26) with a corner cube 27 disposed on a surface (25) opposite to the input surface. An input beam (30) applied to the beamsplitter cube results in two output beams (33, 33'), coplanar with an output optical axis (31), if the input beam deviates at 32 from an input optical axis. The two output beams deviate equally but oppositely from the output axis. This provides signals from which a stable output optical axis may be determined. A polarization-sensitive embodiment is also disclosed which eliminates problems associated with the use of coherent light sources.

Abstract: The axial positions of two or more fibers are simultaneously controlled in three grinding or polishing stages. The fibers (72) are first ground flush with the guide (120) in which they are housed. The fiber ends and faces of the guides are then ground flat and square. The fibers are thereafter polished to their optical quality and required length. The tool for accomplishing these steps includes a retainer (74) which holds the assembly (73) of fiber optic ferrules (70) and their optical fibers (72) therein at a tool surface (16). This tool surface is protected by a guard (18) from being too rapidly ground away while the fibers and fiber/guide combinations are ground flush with the surface. The surface and its retained guides and fibers are then axially moved to an unprotected position (FIG. 3) so that the surfaces and the fibers within their ferrules may be polished on a suitable polishing wheel or similar device.

Abstract: Contacts between polysilicon conductors on the surface of a silicon wafer and doped regions underlying them in the wafer, rendered defective by the growth of a thin intervening oxide layer between conductors and diffusions, are repaired by depositing dots of aluminum on the conductors in the contact areas and annealing the wafer so as to drive traces of the aluminum through the conductors and the intervening oxide into the underlying doped regions in the wafer.

Abstract: Apparatus is provided for detecting the presence of acoustic signals which includes a laser source, and a detector coupled to opposite end of an acousto-optic transducer. The transducer may employ fiber optic waveguides, etched to allow evanescent coupling therebetween, and disposed within a flexible housing. Integrated and planar optic transducers are provided in various forms employing two integrated optic waveguide channels, two planar waveguides, or a planar waveguide and absorber combination. Each configuration is disposed within a flexible housing and the waveguides are separated from each other by a predetermined distance. Any flexing of the housing is transformed into a displacement of the waveguides relative to one another. The coupling between the waveguides is a very sensitive function of distance, and hence detection of variations in the energy coupled by the waveguides provides an indication of the presence of the acoustic signals.

Abstract: This invention provides a unitary oil coupled optical arrangement for color selective prepolarization of the light incident upon two light valves. The optical arrangement is immersed within a single tank. It includes dichroic filters which act on polarized light from a light source which has been polarized into two beams by passing through and being reflected from a prepolarizing optical thin film stack. The first dichroic filter provides light of a first color and a first polarization while the second dichroic filter provides light of a second color and a second polarization. The light from each of the filters is then combined into a single beam by a thin film polarization-selective beam combiner prior to being applied to the main polarizing prism. The main prism then passes light of a first polarization and a first color to a first light valve and light of the second polarization and a second color to the second light valve in a conventional manner.

Abstract: An optical system is disclosed which incorporates a color selective prepolarizer to improve contrast and reduce stress induced birefringence while allowing a blue mirror to be used to enhance the projected image. The invention includes a source lamp for providing a first beam of unpolarized white light energy; a prepolarizing beam splitter which extracts from the first beam, second and third beams. The second beam contains undesirable color components of a first polarization state, which are removed from the system by reflection to an optical dump. The third beam includes prepolarized light of one color and the first polarization and white light of the second polarization. A main polarizing prism is provided for splitting the third beam into fourth and fifth beams having the first and second polarizing states respectively. The main prism effectively directs the white light to the light valve where it is modulated and returned to the main prism for projection in the conventional manner.

Abstract: A first color selective beam splitter is provided for splitting light from a source into first and second beams, the first beam being blue and the second beam having red and green color components.A second beam splitter is provided for directing light of the first beam to a blue liquid crystal light valve. The light valve modulates the polarization of the light in the first beam and returns it to the second beam splitter which converts the modulations of polarization to modulations of intensity in the conventional manner and reflects it to a first projection lens.A third beam splitter is provided for splitting the second beam into third and fourth beams having first and second polarization states, respectively. The third beam is reflected to a red filter. The fourth beam is transmitted through a green filter.The output of each filter is a substantially monochromatic beam of a single polarization state. The filter outputs are recombined into a single beam which illuminates a fourth beam splitter.

Abstract: A polycrystalline silicon field plate underlies a polycrystalline silicon resistor and is heavily doped so that it is virtually a conductor while an aluminum field plate overlies the polycrystalline silicon resistor. Electrical potentials are applied to the polycrystalline field plate and the aluminum field plate, the potentials being selected so that an electric field is created at the boundary between the polycrystalline semiconductor resistor and the surrounding dielectric layer, the electric field forcing charge carriers in the resistor away from the boundary and toward a central region of the resistor. As a result, surface state noise in the resistor is significantly reduced.

Abstract: In a liquid crystal imaging display comprising a liquid crystal layer formed over the top surface of a MOS integrated circuit, the reflectivity of the pixel control electrodes is enhanced by means of a polycrystalline silicon layer formed over the MOS integrated circuit and polished to have an optically smooth surface over which the pixel control electrodes and the liquid crystal may be placed. Contrast ratios on the order of 100 to 1 are achieved.