Abstract: An interferometer includes a two-frequency laser and a polarizing beam splitter (PBS) that separates a heterodyne beam from the laser into separate beams having different the frequencies and orthogonal polarizations. Optical fibers conduct the separate beams to a beam combiner for interferometer optics. The PBS and/or the beam combiner can use a coating to reflect one linear polarization and transmit an orthogonal linear polarization. To improve extinction ratios in the PBS or the beam combiner, a yaw angle for an input beam is non-zero and corresponds to a peak in the extinction ratio of a reflected beam.

Abstract: A switching system includes a first transistor having a first gate and coupled between a first terminal and a second terminal and a second transistor having a second gate and coupled between the second terminal and a third terminal. The first transistor and the second transistor are configured to conduct a signal current between the first terminal and the third terminal. An impedance component coupled to the first gate and the second gate is configured to isolate a first gate signal voltage at the first gate or isolate a second gate signal voltage at the second gate to reduce a distortion of the signal current.

Abstract: An interferometer returns parallel beams that are subject to walk-off caused by reflector misalignment for an additional pass through the interferometer optics and thereby eliminates beam walk-off. A return reflector can be a plane mirror that directs returning beams to retrace paths through the interferometer optics to combine and exit along the axis of the input beam. Separation optics can separate the combined beam from the input beam. Alternatively, a return reflector such as an isosceles prism or a trapezoidal prism reflects and offsets returning beams so that the combined beam is offset from the input beam. The return reflector more generally responds to a shift in incident beam position with a matching shift of the reflected beam in contrast to a retroreflector, which shifts a reflected beam in a direction opposite to the shift in the incident beam.

Abstract: A semiconductor test data analysis system (1) automatically recording, during an analysis operation, operation information of the analysis operation, including analysis conditions or an analysis procedure for input test data, or analysis information obtained by the analysis operation. The analysis system includes a processing means (101), an analysis target data storage means (109), which stores the test data as analysis target data, a historical data storage means (107), which stores as historical data either operation information of the analysis operation or analysis information obtained by the analysis operation, and a display data storage means (112), which stores analysis information obtained by the analysis operation, which stores analysis display data generated by the processing means for the purpose of displaying the analysis information obtained by the analysis operation.

Abstract: An inward opening oven intake for a gas chromatographic (GC) oven includes an inward opening intake flap that opens into the GC oven near the bottom of the GC oven. Opening at a flap angle, the inward opening intake flap creates a low-pressure region to draw a large amount of airflow into the GC oven during cool-down. In addition, the inward opening oven intake manipulates the airflow within the GC oven to more efficiently draw heat away from the oven walls. This greater efficiency allows for faster cycle time and higher sample throughput.

Abstract: A nonpolarization-dependent method and apparatus for optical sampling of a user optical signal of a known frequency range (e.g., corresponding to 1550 nm wavelength) uses a probe signal in an unsplit form and applies a conversion {e.g., by sum frequency generation (SFG)} operation in a first stage to the probe signal and to a first polarization component of the user optical signal (e.g., ‘s’ component) to produce a first component of an output signal. In a second stage, a second polarization component of the user optical signal (e.g., ‘p’ component) is rotated by 90° to align with the first polarization component and then converted by mixing with the unsplit probe signal to produce a second component of an output signal. The first and second output component signals are both added and measured using a photomultiplier tube (PMT) or an avalanche diode.

Abstract: A method and apparatus for analyzing jitter in a signal. The signal is buffered to form a sequence of signal vectors and a time interval error function is calculated for each the signal vector. A time interval error spectrum is then calculated by transforming the time interval error function using a discrete Fourier transform. An average time interval error spectrum and an average power spectral density function are then calculated as averages of the amplitude of the time interval error spectrum and its amplitude squared, respectively. Parameters of the signal jitter are estimated from the average time interval error spectrum and the average power spectral density function.

Abstract: A combination error detector to detect errors in an InfiniBand packet. The detector includes registers that stores fields of an InfiniBand packet as the packet is being received and comparison logic that, as the fields are stored in the registers, compares the fields with check values and when an error is detected sets a flag corresponding to the error. After the packet has been completely received and all checks have been complete, all of the error flags are prioritized in accordance with the InfiniBand Architecture Specification.

Abstract: A micro-machined valve assembly includes a valve diaphragm that will not adhere to a valve seat during elevated temperature operation. The valve assembly has a valve seat, a diaphragm suspended over the valve seat, the diaphragm configured to contact the valve seat upon the application of an actuating pressure on the diaphragm. The diaphragm has a continuous film of a first material, where a portion of the first material in a region where the diaphragm contacts the valve seat includes a first metallic material. The absence of an adhesive or the addition of the metal layer extends the operating temperature of the valve by preventing adhesion of the diaphragm to the valve seat during high temperature operation. Selection of an appropriate material for the metal layer can improve chemical inertness of valve, thereby reducing the possibility that the material flowing through the valve will react with the metal.

Abstract: Disclosed herein is a switch having a photoimaged channel plate and a switching fluid. The photoimaged channel plate defines at least a portion of a number of cavities, a first cavity of which is defined by a first channel formed in the photoimaged channel plate. The switching fluid is held within one or more of the cavities, and is movable between at least first and second switch states in response to forces that are applied to the switching fluid.

Abstract: A method to reduce undesirable outgassing includes bonding at least two optical components with a bonding material and encapsulating the bonding material with a capping material. The capping material inhibits the outgassing of species that would otherwise be emitted from the bonding material to the surrounding. In one example, the bonding material is silicone and the capping material is epoxy.

Abstract: A novel thin wire connector cable and method for connecting an electrical test instrument to an electrical node of interest sealable within a vacuum chamber of an electrical testing device is presented. The thin wire connector cable includes a thin wire cable with a first end connectable to the test instrument and a second end comprising a connector electrically connectable to the electrical node of interest that lies within the vacuum-sealable chamber. The thin wire cable is routed from the vacuum-sealable chamber to the test instrument in between a flexible vacuum seal and an opening to the vacuum-sealable chamber such that when the vacuum is actuated, the thin wire cable is wedged between the seal and testing device. The thin wire cable is substantially thin enough so as to prevent more than a negligible amount of leakage between the thin wire cable and the flexible vacuum seal, which allows a vacuum to be generated and maintained.

Abstract: A light source and method for controlling the same. The light source utilizes a light generator that generates a light signal of a wavelength at an intensity that is set by a control signal. The control signal is controlled by a servo that monitors the light output of the light generator and compares the monitored value with a target value. When the target value is changed, the control signal is initially replaced by a predicted control signal based on the new target value rather than the error signal generated in the servo. This provides time for the servo to adjust to the new target value. In one embodiment, the control signal includes a periodic signal that switches between a value that causes the light generator to generate light of the wavelength and a second value at which the light generator does not generate light of the wavelength.

Abstract: A filter having a thin-film resonator fabricated on a semiconductor substrate and a method of making the same are disclosed. The filter has a bonding pad connected to the resonator and in contact with the substrate to form a Schottky diode with the substrate to protect the resonator from electrostatic discharges.

Abstract: Optical systems for producing modulated light beams are provided. A representative optical system incorporates an integrated package that includes an optical source and an electro-optic modulator. The optical source is operative to produce light that is received by the electro-optic modulator. The electro-optic modulator externally modulates the light so that a modulated light beam is emitted from the integrated package. Methods and other optical systems also are provided.

Abstract: A method and apparatus for determining polarization-resolved scattering parameters of an optical device. A method comprises stimulating a port of the optical device with a stimulation field having at least two polarization states, measuring the optical field emerging from the port in amplitude and phase, and calculating the scattering parameters using the measurements. By stimulating a port of an optical device with a stimulation field having at least two different polarization states, measurements needed to determine scattering parameters of the optical device can be conducted by stimulating the port with only one sweep of a swept optical source.

Abstract: An apparatus includes a device under test, a network analyzer, an internal amplifier, a first switch, a second switch, a third switch, a first air-line directional coupler, and a first attenuator. A method of characterization measurement includes providing a harmonics signal from the device under test to a spectrum analyzer, providing a generated signal and a reflected signal to a first receiver disposed within a network analyzer, and recording a parameter deviation of the network analyzer.

Abstract: An interface to a microcircuit formed on a substrate supporting a ground plane. The substrate supports a dielectric structure having gold coated sloped sidewalls electrically connected to the ground plane. A transmission line, connected to the microcircuit, is supported by the dielectric structure. A coaxial cable is connected to the transmission line. The coaxial cable having an end stripped at an angle substantially the same as the sloped side walls of the dielectric structure, wherein the exposed length of the center conductor is bonded to the transmission line, and the outer conductor of the coax cable is bonded to the gold plating on the dielectric structure such that the angled portion of the coax cable mates with the bevel of the thick film dielectric.

Abstract: Disclosed are methods for predicting board test coverage. In one method, board test coverage is predicted by enumerating potentially defective properties for a board design; determining how each of a number of potential test technologies could be applied to the board design; and predicting board test coverage for one or more combinations of the potential test technologies. Board test coverage is predicted for a combination of potential test technologies by, for each potentially defective property enumerated, generating a property score that is indicative of whether a potential test technology could test for the potentially defective property; and combining property scores to predict board test coverage for the combination of potential test technologies.

Abstract: A switch has a channel plate that defines at least a portion of a number of cavities. A switching fluid is held within one or more of the cavities, and is movable between at least first and second switch states in response to forces that are applied to the switching fluid. A plurality of planar signal conductors extend from edges of the switch to within the one or more cavities holding the switching fluid, and are in wetted contact with the switching fluid. Corners in paths of the planar signal conductors may be limited to greater than 90°, about 135°, or equal to or greater than 135°. In one embodiment, signal path corners are so limited, but the planar signal conductors do not extend to the edges of the switch. In another embodiment, the one or more cavities holding the switching fluid are at least partly defined by a bent switching fluid channel.