Abstract: The present invention is directed to a new test system by which an electric test and an optical test for a liquid crystal display device, such as a liquid crystal panel, can be performed at the same time and under the same conditions, and to enhancing the test accuracy and the test efficiency.

Abstract: A stochastic resonator signal detector comprises a multi-stable nonlinear device for coupling to an input signal and a control signal coupled to the multi-stable nonlinear device for varying asymmetry among stable states of the multi-stable nonlinear device. The interaction of the input signal with the control signal in the multi-stable nonlinear device generates an output signal having an amplitude responsive to the input signal amplitude and a frequency range that comprises harmonics of products of the control signal and the input signal.

Abstract: A contactless process for detecting surface potential charge patterns in an electrophotographic imaging member including at least one photoconductive imaging layer having an imaging surface, providing a scanner including a capacitive probe having an outer shield electrode, maintaining the probe adjacent to and spaced from the imaging surface to form a parallel plate capacitor with a gas between the probe and the imaging surface, providing a probe amplifier optically coupled to the probe, establishing relative movement between the probe and the imaging surface, maintaining a substantially constant distance between the probe and the imaging surface, applying a constant voltage charge to the imaging surface prior to relative movement of the probe and the imaging surface past each other, synchronously biasing the probe to within about .+-.

Abstract: A test method for characterizing retention performance, both same state and opposite state performance, of ferroelectric capacitors includes the steps of writing an original complementary data state into first and second ferroelectric capacitors after the ferroelectric capacitors have been initialized into an initial valid data state. The first and second ferroelectric capacitors are then subjected to time and temperature stress. The original complementary data state from the first and second ferroelectric capacitors is then read, and same state charge (Q.sub.SS) information is collected. An opposite complementary data state is then written in the first and second capacitors. After a short time interval, possibly at an elevated temperature, the opposite complementary data state from the first and second ferroelectric capacitors is read to gather opposite state charge (Q.sub.OS) information. The original complementary data state is then written into the first and second ferroelectric capacitors.

Abstract: A system for detecting a gap of unknown width, the system having an RF signal generator having an output interface that outputs an RF signal and that interfaces with an input portion of a test device that is electromagnetically connected with a first surface of a gap. The system also comprises an RF signal receiver having an input interface that receives an RF signal and that interfaces with an output portion of the test device that is electromagnetically connected with a second surface of a gap. The RF signal receiver generates an electrical output to an output interface when an RF signal is detected. A processor has an input interface that interfaces with the output interface of the RF signal receiver and the processor converts the electrical signal from the receiver into an indication to the user of the presence of a gap in the test device.

Abstract: A battery tub tester is disclosed that tests the individual batteries, battery accessories and connections as they are being assembled into a battery tub for an electric vehicle. The batteries and battery tub accessories, including temperature sensing devices and battery monitor modules, are mounted and electrically connected in the battery tub in accordance with a known battery tub assembly scheme. As the assembler mounts and connects the batteries and battery tub accessories, the tub tester determines the battery voltages of each battery after it is mounted and connected within the tub to determine if the batteries have the desirable voltage and will operate as they are intended and are connected properly. Additionally, the tester determines the temperature readings as the temperature sensors are being mounted, to determine if the temperature sensors will operate as intended and are connected properly.

Abstract: The thickness of the layers of rubber covering the steel belts within a tire can be measured by transmitting a microwave signal toward the outer surface of the tire and measuring the phase shift of the signal reflected by the tire. In the preferred embodiment, a waveguide is used to direct the microwave signal toward the tire. A standing wave is created within the waveguide by interference between the transmitted microwave signal and the microwave signal reflected from the tire. A series of crystal detectors mounted along the length of the waveguide measure the standing wave. A processor calculates the phase of the reflection coefficient, and determines the thickness of the rubber layer as a predetermined function of the phase. By proper selection of the microwave frequency and the spacing between the waveguide and the tire, the rubber layer thickness can be uniquely determined as a function of phase for any range of rubber thicknesses likely to be encountered in a tire.

Abstract: A electrostatic adhesion tester for thin film conductors. In one embodiment, a device is provided for testing the adhesion strength of a thin film conductor that has been formed upon a substrate. The device includes an adhesion tester that is primarily comprised of a conducting portion. The conducting portion is applied to the thin film conductor so that it does not physically contact the thin film conductor, but leaves a small space there between. A power supply may further be provided for coupling to either the adhesion tester, the thin film conductor, or both in order to create a potential difference between the conducting portion and the thin film conductor. The potential difference creates an electric field between the conducting portion and the thin film conductor that induces stress in the thin film conductor.

Abstract: A harmonics survey system includes an induction coil arranged so as to cross over a magnetic flux generated by a current passing a distribution line to be surveyed and adapted to detect a detection current caused by an electro motive force in proportion to the current passing the distribution line, a harmonics detection unit operatively connected to the induction coil and adapted to detect a fundamental component and a harmonic component of the detection current detected by the induction coil, a harmonic current content operation unit for operating the harmonic current content of the harmonic component with respect to the fundamental component detected by the harmonic detection unit, and an indication unit for indicating the harmonic current content operated by the harmonic current operation unit.

Abstract: A vector network analyzer (VNA) has a first harmonic generator multiplying an RF signal by an odd number M1 to produce incident and reflected test signals received at inputs of mixers providing IF signals. A second harmonic generator multiplies an LO signal by an odd number M2 offset by 2 from M1 to provide signals to additional inputs of the mixers providing IF signals. With the harmonic generators providing odd harmonics separated by 2, a single filter removes remaining harmonics from IF signals provided from each mixer. Each harmonic generator includes two step recovery diodes (SRDs) with opposing ends connecting the signal path to ground, the SRDs functioning to cancel even harmonics. A first coupler provides the output of the first harmonic generator to the mixers, the first coupler having a minimal size enabling its output power to increase with frequency.

Abstract: A device in a motor vehicle, with which signals which are generated by a sensor and represent a physical magnitude are transmitted on signal lines. The device includes a voltage divider which is composed of the sensor and at least two impedances which are connected each at one end of the sensor. The signals generated by the sensor are guided, via signal lines connected at its terminals, to a differentiator, by which the usable signal is obtained, and interference signals coupled onto the signal lines are eliminated. Alternatively, the device can also be used for transmission on a signal line pair of any desired potential difference present at an impedance.

Abstract: A sensor is provided with a conductive sensing element that has a composition adapted to provide a resistance large enough that predetermined magnitudes of voltage noise do not create a false indication of removal, e.g. by abrasion or corrosion. Also, the sensing element composition is adapted to provide a temperature coefficient of resistivity small enough that measurements are substantially independent of temperature. Resistance is preferably greater than 10 ohms and the absolute value of TCR is preferably less than 1000 parts per million per .degree. C. The conductive sensing element may be formed from several materials, including alloys of palladium or lead, particularly palladium-gold, lead-bismuth, or lead-palladium. A combination sensor is provided that includes an abrasion sensing element and a corrosion sensing element on the same substrate.

Abstract: A method for determining whether a circuit under test is open is presented. A digital-to-analog converter is dithered to generate a known signal. This known signal is summed with an external attenuation signal which is brought into the system from a probe on the circuit under test. This summation is then measured by an analog-to-digital converter (ADC). If the known signal is not attenuated by the probe (i.e., the ADC measures essentially the known signal), we can conclude that the circuit is open.

Abstract: A method for testing electrical loads in a vehicle electrical system is provided, in which the loads, which are fed by a vehicle battery, are selectively switched on and off. The load-specific current consumption in the switched-on state is determined and assessed in each case. The battery voltage is measured immediately before and shortly after the switching-off of a previously switched-on load in order to determine the load-specific current consumption value from the load-specific battery voltage difference. The internal resistance of the battery serves indirectly as the measuring resistance, which is determined by loading the battery with a known load on a trial basis.

Abstract: A portion of a torsion bar (6) for axially supporting a movable plate (5) of a planar electromagnetic actuator, is made conducting by diffusing boron therein in a high concentration. An external power source can thus be electrically connected to a planar coil (7) via the torsion bar (6) itself. As a result, the possibility of disconnection faults in the electrical wiring due to back and forth twisting movement of the torsion bar is eliminated, thus improving the durability and reliability of the electromagnetic actuator.

Abstract: In a circuit arrangement for measuring the resistance of a resistance sensor, for instance a wetness sensor, which is connected to an evaluation circuit, there is a galvanic separation, formed preferably by an isolating transformer, between the resistance sensor and the evaluation circuit.

Abstract: A method and an apparatus for providing non-contact measurement of waveforms proximate to a surface of a sample. In one version, the describe apparatus includes a probe waveform generator that generates probe waveforms with the same repetition rate as a sample waveform to the measured from the sample. The apparatus includes a cantilever with a signal path to carry the probe waveform to a position above the sample surface where the sample waveform is to be measured. The apparatus of the present invention also includes a gate to periodically route the probe waveforms to the cantilever tip. The gate is controlled by a periodic gating signal with a period substantially longer than the signal period of the sample waveform. In one version, the gate is switched at a repetition rate substantially equal to a mechanical resonant repetition rate of the cantilever. Capacitive coupling between the cantilever and the signal line of the sample results in a periodic motion of the cantilever at the gating repetition rate.

Abstract: An ice detector includes a pair of electrodes connected by a pair of leads to a control unit which measures the total impedance between leads to thereby sense and detect the presence of ice and other contaminants formed on top thereof utilizing a comparator circuit. The electrodes are integrated into patch which can be placed at different locations on an aircraft.

Abstract: A phase noise measurement system including a low noise programmable synthesizer and a receiver/down converter is provided. The low noise synthesizer provides L-Band Signals which can selectively exhibit low noise close-in or low noise far out. The receiver down converter provides for absolute, additive, and down converted/direct/multiple phase noise measurement.

Abstract: A device for testing a battery includes circuitry adapted to measure a first conductance of a first portion of a string of cells that makes up the battery. Further circuitry is adapted to measure a second conductance of a second portion of the string of cells that makes up the battery. Comparison circuitry compares the first conductance and the second conductance and provides an output based upon the comparison which is related to a condition of the battery.