Abstract: In one embodiment a system and method is arranged for bridging the dead-band when asynchronous signals are compared against each other. There is developed a pair of phase related signals from one of the signals, each phase related signal phase shifted from each other, but having the same frequency as the signal from which it was derived. The other frequency signal is compared against each of the phase-related developed signals to generate an error signal which quadrature rotates when the first and second signals are out of frequency with each other. A control signal is generated when the quadrature rotation is outside a certain limit. The error signal is controllably buffered to insure that the error signal only occurs when the frequencies are offset for a selected period of time.

Abstract: An optical component in the form of a right angled triangular prism having a first side, a second side orthogonal to the first side, and a third side generally inclined to the first and second sides to reflect optical radiation incoming from the first side towards the second side. The first and second sides have semi-reflecting surfaces acting as etalon surfaces providing an interferometric pattern. The optical transmittance between the first and the second sides is wavelength dependent and the radiation exiting the second side of the component is rotated 90 degrees to the radiation entering the first side.

Abstract: Optical switches and optical switching methods are provided. One such optical switch includes a waveguide located in a substrate that is at least partially of a non-linear optical material, the waveguide structured to receive an input optical signal, a grating located at least partially in the non-linear optical material, and a first output port optically aligned to a first radiative mode of the grating. The grating exhibits a first radiative mode corresponding to a first intensity of the input optical signal, and a second radiative mode corresponding to a second intensity of the input optical signal. The optical switch may further include a second output port optically aligned to the second radiative mode.

Abstract: An embodiment in accordance with the invention recites a high speed channel selector switch. The high speed channel selector switch includes a first unit that has a plurality of contacts that are operable to electrically couple to a plurality of high speed data lines of a device under test. The first unit also has an additional contact operable to electrically couple to a signal line. The high speed channel selector switch further includes a second unit that is operable to selectively electrically couple one of the plurality of contacts of the first unit to the additional contact of the first unit. The second unit also electrically couples the remaining contacts of the first unit to respective termination impedances. Thus, one of the plurality of high speed data lines is coupled to the signal line via the second unit and the remaining high speed data lines are coupled to respective termination impedances.

Abstract: In one embodiment, a method for reducing signal noise in a relay having pass-through and attenuator circuits which are alternately closed by operation of an armature assembly of the relay is disclosed. In accordance with the method, the armature assembly is provided with a grounding portion. The grounding portion of the armature assembly is oriented to make contact with the pass-through circuit when the attenuator circuit is closed, but not when the pass-through circuit is closed.

Abstract: A method for determining relative movement between an optical navigation device and a navigation terrain includes generating two overlapping coherent optical beams, and generating a pattern of interference fringes between the two overlapping optical beams. The method further includes illuminating a surface portion of the navigation terrain with the pattern of interference fringes, imaging a fringe-illuminated surface portion, and generating a pattern of signals in response to the imaged fringe-illuminated surface portion.

Abstract: An optical communication module includes an optical radiation source as well as control circuitry to control the temperature and the power emitted by he optical source. In order to permit soft start-up of the source while avoiding undesired wavelength variations, the optical source is pre-heated before being caused to emit optical radiation. This may be effected by initially heating the optical source to an initial temperature using the thermoelectrical conditioner associated therewith as a heater and subsequently causing a partly under-threshold current to flow through the source, thus causing the source to be heated while still emitting negligible optical power.

Abstract: A sensor system is mounted on a host for recording motion of the host over time. The sensor system includes a sensor pad having a surface with a positive slope away from a center of the surface, and a mass resting on the sensor pad. The sensor pad includes an array of pressure sensors for determining the location of the mass on the sensor pad. The sensor system can further include a memory and a controller coupled to the memory and the sensor pad. The controller can determine the motion of the host from the location of the mass and record the motion in the memory.

Abstract: A system for fabricating a light emitting device is disclosed. The system contains a growth chamber and at least one nitrogen precursor that is introduced to the growth chamber. The at least one nitrogen precursor has a direct bond between at least one group III atom and at least one nitrogen atom. In addition, the nitrogen precursor is used to fabricate a layer constituting part of an active region of the light emitting device containing indium, gallium, arsenic, and nitrogen, wherein the active region produces light having a wavelength in the range of approximately 1.2 to 1.6 micrometers. A method for fabricating a semiconductor structure is also disclosed. The method comprises providing a substrate and growing over the substrate a layer comprising indium, gallium, arsenic, and nitrogen using at least one nitrogen precursor having a direct bond between at least one group III atom and at least one nitrogen atom.

Abstract: A probe pod housing is connected by a cable to an active probe. The probe pod housing carries a male push-on precision BNC connector that is also a cross-series adapter. The center conductor of the cable receives a male connector that then mates with the non-BNC end of the cross-series adapter. Auxiliary conductors that may also be carried by the cable are connected to male pins (soldered to a circuit board carried within the probe pod) with a push-on female in-line connector. The active probe itself uses a soldered-to-the-shield threaded nut technique. The nut threads into a metallic body that contains the impedance converter and that is enclosed by the body of the active probe. The cable is replaced by first unsoldering the center conductor (and also any auxiliary conductors). Then the nut (which is still soldered to the shield) is unscrewed from the metallic body, and the cable is free from the probe.

Abstract: A closed loop alignment system for cross-connect switches in optical telecommunications systems. Arrays of small tiltable mirrors within the switch direct the signal beams between optical fiber arrays connected to the switch. An external alignment system is incorporated into the cross-connect switch and is employed to provide an alignment beam of a wavelength different from the signal beams. Beam splitters such as dichroic mirrors, which pass the signal beams but pass only a portion of the alignment beams, are placed in the beam paths to image the ends of the optical fibers of the arrays. A combined image of the ends of the optical fibers from each array is reflected onto a photodetector array, output signals of which are sent to a feedback control system for comparison of the combined image to a stored tolerance range and consequently moves the tiltable mirrors as necessary for proper alignment.

Abstract: A source signal is provided. The source signal is XORed with a scrambling random signal to generate a scrambled signal. The scrambled signal is transmitted through the digital logic circuit. The scrambled signal is XORed with the descrambling random signal logically identical to the scrambling random signal to produce a descrambled signal identical to the source signal. In one embodiment, the scrambling random signal is transmitted through the digital logic circuit and used as the descrambling random signal. In another embodiment, the scrambling random signal and descrambling random signal are generated independently using pseudo-random number generators. In yet another embodiment, the scrambling random signal is self-synchronizing and is contained within the pattern of the scrambled signal.

Abstract: Trial decimations are performed on an acquired waveform. Each trial produces a sequence of packets applied to a complexity detection circuit. Each packet contains a decimation value to be used in place of acquisition values to be suppressed along a decimation sample width. Each packet also includes the maximum and minimum values that occurred within the associated decimation sample. A plurality of counters record for a trial decimation the number of instances when the differences in waveform extremes exceed a corresponding plurality of selected thresholds. Complexity introduced by decimation will tend to produce waveforms having larger voltage excursions over the region of suppressed acquisition samples. The data in the counters is processed to produce a suite of histograms examined to select a decimation factor that does not introduce significant additional complexity.

Abstract: A device for testing continuity of electrical paths through a connector of a circuit assembly has a package containing incomplete or no mission circuitry for the circuit assembly. The package is provided with a plurality of contacts for mating to a plurality of contacts of the connector. A test sensor port is integrated with the package. A plurality of passive circuit components are integrated with the package, ones of which are coupled in parallel between ones of the contacts on the package and the test sensor port.

Abstract: Method and apparatus for determining at least one characteristic of a digital data signal. The method includes identifying at least one region of a waveform such as an Eye Diagram that contains information for determining at least one characteristic of interest of the digital data signal. Sufficient samples of the digital data signal are then taken to fully construct only the identified at least one region of the Eye Diagram without fully constructing the entire Eye diagram, and the at least one characteristic of interest is then determined from the fully constructed at least one region of the Eye Diagram.

Abstract: An optical device module for housing optical transmitters and receivers. Preferably, the module is designed to enable optical devices to be easily inserted into and removed from modular equipment racks. The module comprises a case for housing an optical device and a plastic panel having an aperture for receiving an optical connector, in which the plastic panel has been coated with a metal coating and is connected to the case so that the optical device is substantially enclosed.

Abstract: High quantum efficiency point detector system. The system includes a light source generating a light beam having an area and includes a CCD detector with a cell size comparable to the light beam area. The CCD cell may include a single pixel or at least two pixels.

Abstract: A novel two-stage clamp used in testing a device-under-test (DUT) is herein presented. The two-stage clamp provides two sequential actuations via one linear force, and includes clamps moving in multiple different directions. The two-stage clamp uniquely uses the DUT being clamped to provide the linkage and timing for the two-stage actuation of clamps moving in three different directions.

Abstract: A method and apparatus for reducing charge injection in a FET switch. The switch includes a switch FET and two compensating FETs coupled to an input node. Gate drive signals for the two compensating FETs are generated by a gate drive circuit dependent upon the analog input signal and gate drive signal to the switch FET.

Abstract: An integrated buried heterojunction laser optically coupled to a ridge waveguide electro-absorption (EA) optical modulator having a raised ridge structure is manufactured on a single semiconductor substrate on which a plurality of semiconductor layers are grown, including at least one active layer through which optical radiation is coupled from the laser to the waveguide. Semiconductor layers above the active layer form a laser current conduction region and semiconductor layers adjacent the active layer form a laser current confinement region. The ridge structure is formed from one or more layers also used to form the laser current conduction region. The layers used to form the laser current confinement region do not extend adjacent the ridge structure.