Abstract: A planarization and overtravel control circuit is disclosed utilized in conjunction with a multiprobe test system for testing microcircuits disposed on a semiconductor wafer surface. The planarization and overtravel control circuit enables the monitoring of the planarization limit required between data detector probe tips making contact with the integrated circuits on the semiconductor wafer. Overtravel, the distance the data detector probe tips travel into the semiconductor wafer, is also monitored by this apparatus.

Abstract: Output coherent infrared radiation is obtained in a continuously tunable band from 1.4 microns to 25 microns and longer wavelengths. The 1.06 micron output of a Nd:YAG laser, or a harmonic thereof, is difference mixed in a nonlinear crystal, as of LiIO.sub.3 or LiNbO.sub.3 with a synchronously pumped output of a tunable dye laser oscillator to produce a first tunable output over the range of 0.7 micron to 5.0 microns. The output of the crystal mixer is amplified or difference mixed in a second nonlinear crystal mixer with the 1.06 pump output to produce an output tunable over the range of 1.4 microns to 25 microns and longer wavelengths. Suitable second crystal mixers comprise LiNbO.sub.3 for the range of 1.4 to 4.4 microns and operable as an amplifier in the range of 1.4 microns to 2.1 microns, and as a difference mixer in the range of 2.1 to 4.4 microns, AgGaS.sub.

Abstract: A bearing wear detector for an AC rotary electric instrument such as an electric motor or a generator in which more than three detecting coils are mounted around a core of the electric instrument having poles of three or not three multiples at a relative space angle and the detecting coils are connected in series to obtain a resultant voltage.

Abstract: Nonlinear devices using 2-methyl-4-nitroaniline are described. Devices using 2-methyl-4-nitroaniline as the active element include second harmonic generators, optical mixers and parametric oscillators which can be operated under phasematched conditions.

Abstract: A time of day demand metering system is disclosed for registering the amount of electrical energy consumed during the one demand interval of maximum electrical energy consumption out of a plurality of demand intervals. Means is provided to engage the register of a time of day meter only during those demand intervals when the amount of electrical energy being consumed is in excess of the one previous demand interval of maximum electrical energy consumption.

Abstract: The gas discharge panel described here is an AC plasma display panel with electrodes arranged on a substrate, and the electrodes and substrate are coated with a dielectric layer for insulation from the gas filled discharge space, with an improvement in the dielectric layer surface. The improvement being an overcoat layer of at least two alkaline earth compounds, especially CaO and SrO, provided on the dielectric layer surface of this display panel. This overcoat layer significantly lowers the operating voltages of the panel.

Abstract: A swept frequency circuit for use with several detectors and an oscilloscope is described, the output of which is controlled remotely by an electronic attenuator. A closed feedback loop is formed by a detector rectifying the swept output frequency as it is swept from low to high frequency during one half of the sweep cycle (determined by the sweep rate). This recitified signal is processed through switchable attenuators or resistors and applied to the electronic attenuator so as to decrease the output of the swept frequency signals. In particular, the switchable attenuators or resistors can be arranged to produce an upper and lower calibration trace, forming a "window" of, for example, .+-.1 dB, as well as several test traces so that several events may be measured simultaneously in the "window".

Abstract: A capacitor divider type high alternating voltage monitoring apparatus incorporating a filter with a switchable gain/frequency characteristic for removing the effect of d.c. voltage error arising from trapped charge on the capacitor divider.

Abstract: Disclosed is a test site for an integrated circuit chip including a CCD register. Two serial CCD registers are spaced from each other at incrementally variable intervals. The first register receives a serial bit stream having a first binary value while the second serial register receives a bit stream having a second binary value. Data is transferred in parallel from the second register to determine the point at which the spacing between the two registers is sufficiently close to permit undesirable cross-talk.

Abstract: In apparatus for indirectly measuring the output DC current of a rectifier device on the input side of a polyphase rectifier transformer, a polyphase auxiliary current transformer is provided and the polyphase primary or secondary windings thereof are combined such that the area of the decreasing secondary current waveform is made equal to the area of the increasing secondary current waveform during commutation thereby releaving the secondary current from the adverse effect of the overlap angle.

Abstract: Portable tester and method for testing a variety of circuit boards without utilizing adaptor boards for re-routing input test signals and supply voltage from the tester to pins of the board under test. A plurality of edge adaptors having different pin spacings have their respective pins connected in parallel to corresponding edge connector stake pins. Each edge connector stake pin is connected to or isolated from the corresponding driver/sensor stake pin by means of a switch. Each driver/sensor stake pin is connected to the input/output terminal of a programmable driver/sensor circuit. A plurality of power supply stake pins are connected to various power supplies of the portable tester. Connectors coupled to the family board can be utilized to route power supply voltages to electrically isolated edge connector stake pins. Isolated driver/sensor outputs can be routed to other edge connector stake pins.

Abstract: A probe assembly for measuring the speed of rotation of a gas-turbine engine compressor shaft has a sensor head mounted at one end of a tubular probe body by means of a bellows unit which permits limited axial displacement of the sensor head relative to the probe body. The sensor head has a sleeve sealed to its rear end, one end of the bellows unit being sealed to the sleeve and the other end being sealed to the probe body. The forward end of the probe body extends through the bellows unit and into the sleeve where it is resiliently coupled with the sensor head by a helical spring. Four outwardly inclined leaf springs are mounted on the end of the probe body within the sleeve and are resiliently urged against the inner surface of the sleeve so that they are free to slide over the surface of the sleeve while separation of the sensor head from the probe body is limited by engagement of the springs with an inwardly projecting lip on the sleeve.

Abstract: A multiprobe test system is disclosed for testing microcircuits which includes a printed circuit board having a plurality of data-detector probes attached for z-axis control and edge detection. The data-detector probes include a support body, and an arm supported by the body and attached thereto in an angular fashion. A probe tip in the form of a needle extends from and is attached to the arm. The probe tip includes a downwardly positioned point for contact with the surface having integrated circuits defined thereon. A force sensitive material is attached to but electrically isolated from the arm and has conductor leads extending therefrom. The force sensitive material comprises a piezoelectric material, for example.

Abstract: A method and an apparatus for characterizing magnetic materials especially LPE garnet films for magnetic bubble memory applications are described. The method and apparatus comprises in the first embodiment passing monochromatic linearly polarized light through a magnetic film, under no applied external field (Ha=0) with a randomly oriented stripe domain structure to produce a single diffraction grating, then (1) the angle of the first order diffracted beam is deduced by directly comparing the currents produced by a linear position photodetector and an ordinary intensity photodetector and (2) next a magnetic field (Ha) is applied normal to the surface of the film and the field is increased until intensity of the second order diffraction beam is maximized. In the second embodiment of the method so that higher signals can be detected for the first order diffracted beam, the film is magnetized so that the stripe domain configuration is parallel and the foregoing steps followed.

Abstract: Deterioration of a dry developing substance causes toner particles to be so strongly adhered to carrier particles that they cannot be readily separated therefrom. The present apparatus comprises means for applying a predetermined electrostatic or air suction force to the developer to readily remove toner therefrom except for spent toner particles strongly adhered to the carrier particles. The toner density, or the ratio of toner to carrier particles, is then measured electromagnetically or optically and compared to a reference value. The developer deterioration determines what proportion of toner will be removed from the developer by said force and thereby the subsequently sensed toner density. The higher the sensed toner density, the greater the degree of deterioration.

Abstract: The scanning microwave detection apparatus provides a moisture profile along the width of a predetermined sample such as a sheet or web. The apparatus includes a number of moisture sensors spaced along the width of the sample, such that each sensor couples microwave energy with a finite area of the sample. Each sensor is preferably a pair of horns with one located on each side of the sample to provide a microwave path through the sample. A first filter is coupled to the input of each sensor and a second filter is coupled to the output of each sensor. The pair of filters associated with each sensor is tuned to the same frequency, and each of the pairs of filters are tuned to a different predetermined frequency within a selected frequency band such that the sensors operate at different frequencies, within substantially non-overlapping frequency band-passes. The filters are preferably directional.

Abstract: An electronic circuit to be used in conjunction with eddy current non-destructive flaw detection instrumentation for distinguishing from noise or other undesirable signals a flaw signal having a characteristic frequency and a negative excursion followed by a positive excursion. The circuit includes two channels, each of which comprises a threshold detector, a differentiator, a filter, and a variable pulse width one-shot multivibrator, each of which receives the characteristic signal. One channel processes the negative excursion, and the other channel processes the positive excursion. Each channel produces a pulse of predetermined time duration if the excursion being processed exceeds a predetermined threshold. The leading edge of the pulse produced in association with the negative excursion corresponds in time to the time at which the trailing positive going edge of the negative excursion crosses a predetermined negative threshold.

Abstract: Instrument for the non-destructive detection of contamination on the surface of a metallic object. A reference electrode contains sufficient radioactive material to ionize the air in a gap between the electrode and the metallic object. A buffer amplifier has its input terminals connected to sense the surface potential difference between the electrode and the metallic object. The air gap is typically from one to ten millimeters wide. The input circuit of the buffer amplifier has a resistance very much larger than that of the air gap when the air is ionized. The buffer amplifier drives an alarm device or a display device. A single voltage pick-up is conveniently embodied in a portable hand-held probe. A plurality of voltage pick-ups is incorporated into an array for simultaneously making multiple measurements of surface condition over a large area.

Abstract: The magnitude and sign of the Hall angle of the material of a wafer (13) are measured by a combined capacitive and inductive coupling technique which does not require physically contacting the wafer (13). Contacting methods in common use introduce surface damage or contamination which may reduce the yield of microelectronic circuits on semiconductor wafers and normally in addition require special sample geometries. In this technique an rf signal is applied to a pair of concentric planar electrodes (11,12) adjacent to the wafer (13), thus capacitively coupling a radial rf current into the wafer. A magnetic field applied perpendicular to the wafer produces a circular component of rf current because of the Hall effect. This circular rf current produces an axial rf magnetic field which couples to a pickup coil (15). The pickup signal is amplified and detected to produce an output signal related to the sign and magnitude of the Hall angle of the wafer material.

Abstract: A signal transducing means for receiving input signals and delivering output signals comprising a bistable magnetic device which alters its magnetic state when the density of magnetic flux to which it is subject passes through a predetermined value, and detecting means providing an output signal responsive to a change in magnetic state of the bistable device. A conducting means for magnetic flux subjects the bistable magnetic device to conducted magnetic flux and comprises a first portion providing a path of high permeability and a second portion providing a path having a permeance which is alterable in response to input signals for varying the reluctance of the conducting means and the density of magnetic flux to which said bistable device is subject.