Abstract: An oxide layer on an indium phosphide semiconductor substrate is doped with silicon. This enables epitaxial layers to be deposited upon the substrate in a conventional manner, including mesa etching and overgrowth, to form a semiconductor structure. The doped oxide layer is thought to reduce diffusion of phosphorus out of the substrate and thus to reduce the zinc levels in the active region of the structure. Additionally, or as an alternative, after mesa etching oxide can be formed on the mesa sides and then doped with silicon. Conventional blocking layers can then be formed over the doped oxide, reducing the diffusion of zinc from the blocking layers into the rest of the structure.

Abstract: An x-ray laminography imaging system and an apparatus and method for calibrating the system. The x-ray laminography imaging system utilizes a stationary x-ray source and generates a moving pattern of x-ray spots on a target anode synchronously with rotation of an x-ray detector to reduce or eliminate the need to move an object being imaged. The present invention provides an apparatus and a method for calibrating the system based in part on empirical data gathered during physical calibration and in part on data analytically derived from the empirical data. Because calibration of the system can be performed in great part analytically rather than relying entirely on empirically generated data, the calibration process can be performed very quickly.

Abstract: A method and apparatus correct for image brightness of images taken of an object with point source illumination in an imaging system. The brightness correction method and apparatus of the present invention correct for the non-object related brightness characteristics of a point source illumination in the observed or measured brightness of a relatively planar object being imaged by the imaging system. The method and apparatus are applicable to imaging and inspection systems used with a wide variety of planar and semi-planar objects including but not limited to X-ray inspection of printed circuit boards (PCBs) and integrated circuits.

Abstract: Systems and methods of passivating planar index-guided oxide vertical cavity surface emitting lasers (VCSELS) are described. These systems and methods address the unique susceptibility of these devices to damage that otherwise might be caused by moisture intrusion into the etch holes that are used to form the index-guiding confinement regions. In one aspect, the invention features a VCSEL that includes a vertical stack structure having a substantially planar top surface. The vertical stack structure includes a top mirror, a bottom mirror, and a cavity region that is disposed between the top mirror and the bottom mirror and includes an active light generation region. At least one of the top mirror and the bottom mirror has a layer with a peripheral region that is oxidized into an electrical insulator. The vertical stack structure defines an etched hole that extends from the substantially planar top surface to the oxidized peripheral region.

Abstract: The present invention is directed to a control system for a photolithographic integrated circuit manufacturing process. The control system incorporates a visual gating device in which a series of nests are provided. A barcode reader may be provided in conjunction with some of the nests. In operation, a human operator advances wafer lot boxes through the nest positions in accordance with a series of displays which are controlled by the control system. The barcode reader associated with each nest reads a barcode label on the wafer lot box contained within the nest to determine the lot number corresponding to the lot box. This lot number is then used by the control system to obtain setup parameters for the various photolithographic manufacturing process operations.

Abstract: A dual mode amplifier having single ended and differential ended modes of operation using only one set of output pads or terminals. The dual mode amplifier has two differential amplifiers, connected by coupling circuitry, each differential amplifier receiving a pair of differential input signals and having one output terminal. By activating and deactivating the coupling circuitry, the differential amplifiers can operate in two modes using the one set of output terminals. In the singled ended mode, the differential amplifiers operate independently, each converting the differential input signals to a singled ended output signal at their respective output terminals. In the differential mode, the differential amplifiers operate together to provide a pair of differential output signals at the output terminals based upon the pair of input signals.

Abstract: An optical switch has a plurality of input ports and a plurality of output ports. The optical switch features a fan-out fan-in architecture has a fan-out stage, a fan-in stage, and a coupling mechanism. The fan-out stage is coupled to the plurality of input ports and has a first orientation. The fan-in stage is coupled to the plurality of output ports and has a second orientation. The coupling mechanism optically couples the fan-out stage with the fan-in stage and maintains a predetermined relationship between the first orientation of the fan-out stage and the second orientation of the fan-in stage.

Abstract: Optical signal storage devices are described. In one aspect, an optical signal storage device includes an optical memory loop and a substrate. The substrate carries an input optical port, an output optical port, an optical signal path that is coupled between the input and output optical ports, an optical memory path that is coupled to complete the optical memory loop, and an optical read/write controller that is coupled between the optical signal path and the optical memory path. The optical read/write controller is operable to selectively transmit light between the optical signal path and the optical memory path based on received control light. In another aspect, the optical read/write controller comprises at least one saturable absorber optical switch having a transmittance that varies nonlinearly with received light intensity so that light is selectively transmittable between the optical memory loop and the input and output optical ports based on received control light.

Abstract: An arrangement for monitoring the emission wavelength of a laser source emitting a main radiation beam to be launched into an optical waveguide includes a wavelength selective photosensitive element adapted to be exposed to the radiation beam to generate an output signal indicative of the wavelength of the radiation. The arrangement comprises an optical system defining a beam propagation path for the radiation beam towards the waveguide. The wavelength selective photosensitive element is arranged at a marginal position of the beam, to collect at least a corresponding marginal portion of the radiation beam, whereby the signal indicative of the wavelength of the radiation is generated from said marginal portion of the radiation beam in the optical system.

Abstract: A through-panel apparatus includes a device with at least one through-panel receptacle and at least one component removably mounted to the device by inserting the component through the receptacle. Both the device and component have between them electrical and/or optical connections that are made when the component is mounted to the device, and broken when the component is demounted from the device. To break the connections requires the application of an extraction force in a direction opposite to that of insertion of the device through the receptacle. The component has a sprung mechanism that is biased against the device when an insertion force is applied to the component along the direction of insertion during mounting of the component to the device. The biasing of the sprung mechanism provides a spring bias force that contributes to the required extraction force to aid extraction of the component from the receptacle.

Abstract: A phase-locked loop oscillator with loop gain compensation. The phase-locked loop oscillator includes a phase comparator, a loop filter, a voltage-controlled oscillator, a control device, and a variable-gain amplifier disposed between the phase comparator and the loop filter. The oscillator detects the output signal voltage of the loop filter and controls the amplification rate of the variable-gain amplifier so that the loop gain is compensated and held constant, without sacrificing continuity.

Abstract: A method and structure for an optical switch. According to the structure of the present invention, a liquid-filled chamber is housed within a solid material. A plurality of seal belts within the liquid-filled chamber are coupled to the solid material, while a plurality of piezoelectric elements are coupled to a plurality of membranes. The plurality of membranes are coupled to the liquid-filled chamber, and a plurality of optical waveguides are coupled to the liquid-filled chamber. The plurality of seal belts are coupled to a plurality of liquid metal globules, wherein one or more of the plurality of liquid metal globules are coupled to a slug. According to the method, one or more piezoelectric elements are actuated, causing one or more corresponding membrane elements to be deflected.

Abstract: A system and method is provided for processing a demosaiced image using a color aliasing artifact reduction (CAAR) algorithm in order to reduce color aliasing artifacts. The CAAR algorithm computes the L level wavelet transform for the demosaiced color planes R, G and B. Thereafter, the CAAR algorithm estimates the correct color value at each pixel location for the colors not associated with that pixel location. For example, to determine the green value at red pixel locations, the CAAR algorithm performs an inverse wavelet transform using the green approximation signal and the red detail signals. This process is repeated for each of the colors (e.g., green values at blue pixel locations, red values at green pixel locations, etc.). In addition, the CAAR algorithm performs an inverse wavelet transform on each of the color planes themselves, so that the pixel values of the color associated with each pixel location are not altered.

Abstract: A method and apparatus for flattening the illumination intensity over an optical sensor is disclosed. The intensity of light off the axis from a lens is less than the light on axis by a factor of cos4&thgr;, where &thgr; is the angle from the lens exit pupil to the off-axis point. Light from the lens incident upon the optical sensor therefore will not be uniform in intensity. Light-blocking patches are placed over the areas of the optical sensor where light intensity needs to be reduced to achieve uniform illumination intensity across the entire optical sensor. Areas of the optical sensor that fall closest to the axis of the lens receive the greatest intensity of light due to the rule of cos4&thgr;, and therefore will require more light-blocking patches than areas of the optical sensor further away from the lens axis.

Abstract: A mounting arrangement for an optical component (14 to 18) in a planar lightwave circuit (PLC) includes:

Abstract: In a device to operate and handle a laboratory microchip to chemically process or analyze substances, the microchip is on a chip holder (41) that is part of a first assembly (42). The first assembly (42) also has an optical device (43) for contactless detection of the results of the chemical processes carried out on the microchip. A supply device (56) required to operate the microchip is in a module releasably connected to a second assembly (44, 55). In particular, the second assembly (44, 55) has an intermediate carrier (57) that is releasably connected to the supply device (56). The intermediate carrier has continuous electrical paths (60) or connecting channels that can bridge electrodes (58) or supply channels of the supply device (56) and the assigned counterelectrodes (53) of the microchip. There are correspondingly connecting lines (61) to bridge the supply of materials.

Abstract: A measurement apparatus for an optical signal under test includes a closed-loop optical path, an optical mixer in the closed-loop optical path and a photodetector. The optical signal under test and sampling light having a wavelength different from that of the optical signal under test are circulated in the closed-loop optical path. Sum/difference frequency light is generated every time the sampling light passes through the optical mixer. The sum/difference frequency light is detected by the photodetector, which provides a signal representative of the waveform of the optical signal under test.

Abstract: A method and structure for an optical switch. According to the structure and method of the present invention, a gas-filled chamber is housed within a solid material. A plurality of contacts within the gas-filled chamber are coupled to the solid material, while a plurality of piezoelectric elements within the gas-filled chamber are also coupled to the solid material. A slug within the gas-filled chamber is coupled to one or more of the plurality of contacts and further coupled to one or more of the plurality of piezoelectric elements. A liquid metal within the gas-filled chamber is coupled to the slug, and coupled to the plurality of contacts. The actuation of the one or more piezoelectric elements causes the slug to move from a first number of contacts to a second number of contacts wetted by the liquid metal.

Abstract: Support structure for high frequency coaxial transmission line. A conductive bead ring is split in two halves longitudinally, containing a relief for excess glass flow and provision for locking the halves together. A glass dielectric surrounds the center conductor, which is tapered from a first larger diameter to a second smaller diameter in the region of the glass dielectric. A fixture for forming the glass to metal seal uses dams to control the positioning of the glass with respect to the taper in the center conductor.

Abstract: An interpolation circuit and method for interpolating first and second out-of-phase ramp signals are disclosed. The interpolation circuit generates fractional ramp signals from the ramp signals and utilizes four multiplexers and two comparators to compare selected ones of the ramp signals. The comparator outputs are used by a finite state machine to provide a next state for the interpolator from the current state and the comparator outputs. The signals selected by the multiplexers are determined by the current state generated by the finite state machine. The finite state machine also detects a startup condition and determines the correct current state from the comparator outputs when different ramp signals are applied to the comparators. The ramp signals can be generated from out-of-phase signals from an optical comparator. The interpolation circuit generates new out-of-phase signals having a larger number of states per cycle.