Abstract: A doped, metal oxide dielectric material and electronic components made with this material are disclosed. The metal oxide is a Group III or Group VB metal oxide (e.g. Al.sub.2 O.sub.3, Y.sub.2 O.sub.3, Ta.sub.2 O.sub.5 or V.sub.2 O.sub.5) and the metal dopant is a Group IV material (Zr, Si, Ti, and Hf). The metal oxide contains about 0.1 weight percent to about 30 weight percent of the dopant. The doped, metal oxide dielectric of the present invention is used in a number of different electronic components and devices. For example, the doped, metal oxide dielectric is used as the gate dielectric for MOS devices. The doped, metal oxide dielectric is also used as the inter-poly dielectric material for flash memory devices.

Abstract: In a method of making a flip-chip bonded GaAs-based opto-electronic device, removal of the GaAs substrate is facilitated by provision of a lattice matched (Al.sub.x Ga.sub.1-x)InP etch stop layer, exemplarily a Ga.sub.0.51 In.sub.0.49 P layer, and use of an etchant that isotropically etches GaAs such that an essentially mirror-like etch stop layer surface results, and that preferably exhibits an etch rate ratio of at least 200:1 for GaAs and the etch stop layer, respectively. Use of the novel substrate removal method can substantially increase device yield, and facilitate manufacture of large device arrays, e.g., arrays of detector/modulator diodes flip-chip bonded to Si CMOS chips.

Abstract: An optical fiber amplifier is pumped by a fiber pump laser which has a pair of separate active media within a common resonator. The fiber gain section of the amplifier is also located within the resonator.

Abstract: A cable rotary joint includes a spool support and a stator spool mounted on the support and having a spool axis. The stator spool holds one portion of a cable segment having a first cable end and a second cable end, and allows the first cable end to connect with a stationary cable interface in a downstream direction from the stator spool. A rotor spool mounted for rotational movement about the spool axis holds a remaining portion of the cable segment, and allows the second cable end to connect with a rotating cable interface in an upstream direction from the rotor spool. The cable segment may be a ribboned fiber-optic cable, to meet applications in which any fiber-optic core cable is deployed from a ship. A tension wind assembly between the stator and the rotor spools includes a pulley set for transporting the cable segment from one of the spools to the other in response to rotation of the rotor spool.

Abstract: The present invention is a three port optical circulator including a reflective device such as a mirror. Advantageously, the incorporation of the mirror into the circulator of the present invention enables two ports of the circulator to be terminated using a dual fiber termination and a shared collimating system such as a single GRIN. According to one advantageous embodiment of the invention an optical apparatus of the present invention comprises first and second polarization splitter/combiners including walk-off devices having a splitting end and a combining end. The polarization splitter/combiners further include a polarization interchanger disposed proximate input/output ports at the combining end of the walk-off device.

Abstract: The present invention provides an optical fiber buffer loop management system which may be incorporated into a conventional interconnection box and which comprises one or more spools or pins around which optical fiber buffer loops are loosely dressed. Strategically placed cover guards forming narrow insertion slots for the fibers are attached to the tops of the spools or pins to prevent the fibers from unraveling. By loosely dressing the fiber loops in the interconnection box, no excess slack exists in the portion of the loop running from the spool to the point at which the plug connector on the end of the buffer loop is connected to the coupling located inside of the interconnection box. Preferably, each of the buffer loops is loosely wrapped about two spools in a figure-of-eight configuration, which allows a buffer loop density approximately four times greater than that of the prior art systems to be achieved without bending the fibers beyond their minimum bend radii.

Abstract: A method of cleaning fiber of dust and particulate matter thereon includes the steps of directing the fiber passage having an entrance end and an exit end; protecting the fiber from abrasion at the entrance end and the exit end; passing the fiber through a vacuum chamber in the fiber passage; directing a fluid spray against the fiber in a direction opposite to the direction of movement of the fiber along the passage at a velocity sufficient to dislodge particulate matter from the fiber; and exhausting the fluid and the particulate matter from the vacuum chamber.

Abstract: A track ball device includes a ball having a pattern of first conductive features and a socket into which the ball rotatably sits, the socket having a pattern of second conductive features. Also disclosed is a sensing array system for determining relative motion including a first substrate having a plurality of interstitially arranged electrodes provided thereon. A second substrate has a plurality of transfer electrodes provided thereon. The first and second substrates are movable relative to each other, and the plurality of interstitially arranged electrodes selectively operate as driving electrodes for providing a plurality of signals to the sensing array and as collecting electrodes for collecting signals capacitively transferred from the driving electrodes by the transfer electrodes. The sensing array is useful in a battery operated track ball device, a mouse or other device that must be able to determine relative motion over two degrees of freedom.

Abstract: Enhanced alignment of a mechanical optical switch is achievable using two optical fiber structures containing corresponding arrays of optical fibers fixed to first and second substrates cleaved from a common substrate. In an exemplary embodiment, an array of optical fibers is fixed to a common substrate substantially parallel to one another. The resulting structure is cleaved across the optical fiber array to produce cleaved structures. The enhanced optical fiber alignment at the cleaved edges is provided by securing particular respective surfaces of the cleaved substrates to surfaces of two bases aligned in a common plane. Such enhanced alignment occurs in a direction normal to the plane of the surfaces of the bases. Alignment of the optical fibers in a direction parallel to this plane and optical connections between optical fibers of the respective structures occurs by moving the second cleaved structure relative to the first cleaved structure in a direction along the cleaved edges.

Abstract: We have found that it is possible to make a multistage optical fiber amplifier having a substantially flat gain band of spectral width of 40 nm or more, excellent noise figure (e.g.,<4 dB) and output power. Such amplifiers can advantageously be used, for instance, in multichannel WDM systems and analog CATV systems. A significant aspect of the amplifier is the provision of an optical loss element (exemplarily a multi-grating optical fiber filter) that provides, at least at one wavelength in the gain band, an attenuation of more than G/3 dB, where G is the average amplifier gain (in dB) in the gain band. A further significant aspect of the amplifier is the use of relatively longer amplifier fibers, which facilitates attainment of high output power and low noise figure. Exemplarily, the amplifier is a 2-stage amplifier comprising silica-based Er-doped amplifier fiber, with three-Gaussian filters between the stages.

Abstract: An improved complementary logic driven level shifter which typically improves switching speed over the prior art diode-type circuit, and allows for symmetrical delays for both high-to-low and low-to-high transitions, thus reducing settling times. The complementary CMOS and not-CMOS inputs to the level shifter are applied to the gates of a pair of P-channel FETs and also to the gates of a pair of N-channel FETs. The sources of the P-channel FETs are coupled to a current source. The drain of each P-channel FET is coupled to the drain of the N-channel FET to which its gate is coupled, and also to the anode of a diode. The cathodes of the two diodes, and the sources of the N-channel FETs are coupled together to the anode of a grounded cathode diode. The output SELECT is the common connection point of the drains of the FETs whose gates are coupled to not-CMOS, and the complementary not-SELECT output is the drains of the FETs whose gates are coupled to CMOS.

Abstract: A system and method are described for assigning downstream and upstream communication pathways in broadband access networks, such as networks based on the hybrid fiber-coax architecture. In the upstream direction, frequency channel and time slot assignments use a packing opposite methodology, which is dependent on the type of service request. The system assigns the lowest time slot in the lowest frequency available for a DSO service request and the highest time slot in the highest frequency which has the next four contiguous time slots available for an H0 service request. To optimize upstream bandwidth efficiency, a H0 channel occupying the space of four contiguous time slots is used to carry up to six simultaneous voice conversations. A method is described that governs such use of H0 channels by NIUs according to their offered loads.

Abstract: An arrangement for cooling a heat dissipating circuit element mounted to a first side of a printed circuit board. A heat dissipation member is mounted to the other side of the circuit board and a thermally conductive post secured to the heat dissipation member extends through an aperture through the circuit board and into thermal contact with the circuit element.

Abstract: An arrangement for transmitting data messages from a source to a plurality of destinations. A single file set stores messages from the source, but a plurality of processes transmits the messages to the destinations. A particular destination can receive the messages by having a process for such transmission. Advantageously, the source need not have a record of the identity or number of the destinations.

Abstract: A laser module uses series connected thermoelectric coolers to maintain lasers at the proper operating temperature. A variable resistance associated with the thermoelectric cooler is adjusted to maintain the current through the cooler at the proper value.

Abstract: An optical waveguide router is provided with a control arrangement that is bonded to the silicon wafer of the router to deform the arms of the grating of the router to change their optical lengths in the same proportion with little strain in the direction normal to that of the waveguide arms to minimize birefringence effects.

Abstract: Each microminiature contact pad included in a dense array of pads on an electronic component contains a relatively thick layer of solder. The layer is treated to form a relatively thin brittle protective layer on the surface of the solder. The structure is then brought into contact with a contact pad in a mating array of pads on another component in a thermo-compression bonding step carried out below the melting point of the solder. In that step, the brittle layer is fractured. As a result, solid-state diffusion of conductive material occurs through fissures in the fractured layer, thereby to provide an electrical connection between mating pads on the two components.

Abstract: Feedback is employed in a holographic memory system to facilitate rapid access to information in a stored data page. This feedback technique provides compensation for thermal, optical and/or mechanical variations in the system components that tend to interrupt the projection of a data page image on a sensor array. A page indicator or mark is stored in a holographic storage medium with a page of data such that, during playback, a quality, e.g., intensity, of its projected image is indicative of the quality of the corresponding projected data page image. A corresponding page indicator sensor is employed with the associated sensor array to detect the quality of a projected page indicator image. The projected data page image can then be read by sensor elements of the detector based on the detected quality of the page indicator image. Such a detector can be implemented in an active pixel sensor (APS) array with the page indicator sensor being implemented as a region of the APS array.

Abstract: An uninterruptible power supply (UPS) for supplying DC power to a load and a method of providing uninterruptible DC power to a load. In one embodiment, the UPS includes: (1) a first stage rectifier that rectifies AC input power received from a primary power source into DC power at an intermediate voltage, (2) a second stage rectifier, coupled to the first stage rectifier, that converts the DC power at the intermediate voltage into DC power for the load at an output voltage that is lower than the intermediate voltage and (3) a solid state transfer switch, coupled between the first stage rectifier and the second stage rectifier, that transfers secondary input power received from a secondary power source to the second stage rectifier only when a voltage of the secondary input power exceeds the intermediate voltage.

Abstract: A flexible communications systems provides users with additional communication channels without requiring additional transmitters or receivers by using variable rate Walsh coding. Additionally, the assignment of these additional communication channels is easily managed at the base station by monitoring data backlog and receiver error rates.