Showing papers on "Electrode array published in 1973"

Driving system or liquid crystal display device

Abstract: A driving system for a liquid crystal display device includes a first and common electrode, a plurality of second electrodes, and a liquid crystal interposed between the first and second electrodes and has a visual threshold voltage at which the state of the liquid crystal changes visually. A potential difference not smaller than the visual threshold voltage is applied between the first electrode and a selected one or more of the second electrodes. A medium potential between potentials applied to the first electrode and to the selected second electrode or electrodes is applied to the second electrodes which are not selected. The potential difference between the medium potential and the potential applied to the first electrode is smaller than the visual threshold voltage.

Capacitive voltage-dividing arrangement for high voltage measuring apparatus

Abstract: In a capacitive voltage-dividing device of the type having a high-voltage capacitor connected in series with a low-voltage capacitor for high voltage measurements, particularly in connection with fully insulated, metal clad, high voltage switchgear, an improved arrangement comprises an inner electrode connected to the high voltage bus of the switchgear and extending through an opening in the metal cover; an intermediate or measuring electrode surrounding the inner electrode; and an outer electrode forming a cap-like extension of the metal cover and surrounding the measuring electrode in spaced, insulated relation. The measuring electrode in combination with the inner electrode forms the high voltage capacitor, and the measuring electrode in combination with the outer electrode forms the low voltage capacitor of the arrangement.

Method and apparatus for measuring pitting corrosion tendencies

Abstract: A Cathode, an Anode wrapped in filter paper or other barrier to oxygen diffusion, a Reference Electrode (and optionally an Auxiliary Electrode) are placed in an aerated electrolytic liquid The open circuit potential between the Cathode and Reference Electrode is impressed upon a capacitor By means of a two-position switch an operational amplifier then causes the potential of the anode, in a circuit including the Reference Electrode, Auxiliary Electrode (or the electrode previously used as the Cathode) and an Ammeter, to become equal to the open circuit cathode-reference electrode potential impressed upon the capacitor The amplifier provides the necessary current of either polarity to achieve the equality The polarizing current flowing through the Ammeter is read and a qualitative indication of the pitting tendency is obtained

Method and apparatus for determining the presence of and depth to a horizontal electrical resistivity contrast beneath the earth surface

Abstract: Method and apparatus for determining the presence of and depth to a horizontal electrical resistivity contrast lying beneath the bottom of a borehole. The apparatus comprises a surface generator for applying a low frequency sinusoidal current between a long downhole current electrode unit and a distant surface current electrode. The apparatus further includes a voltage-measuring device for recording the resulting potential difference between two long downhole potential electrode units. The centers of the two long downhole potential electrode units are equally spaced several hundred feet above and below the long downhole current electrode unit, respectively. The exact spacing is chosen according to the desired depth of investigation. Another aspect of the apparatus is that the length of each downhole current and potential electrode unit is made equal to about one-tenth the chosen vertical electrode spacing. The method includes measuring the amplitude of the potential difference measured between the two long downhole potential electrode units and displaying in a log-log plot the potential difference over the low frequency sinusoidal current versus the difference of the electrode array above the bottom of the borehole and determining therefrom the distance from the bottom of the borehole to the level of electrical resistivity contrast.

Circuits for driving and addressing gas discharge panels by inversion techniques

Abstract: Opposed electrode arrays are driven from busses on which assymetric, periodic pulsating, sustainer voltage components are imposed by pull-up, pull-down and pull to ground circuits to energize display/memory gas discharge panels made up of a plurality of discharge cells, each cell including proximate electrode portions of at least one electrode in each opposed array. A pull-up buss and a pull-down buss is provided for each electrode array and each is coupled to each electrode of the array by isolation diodes. The device is subjected to electronic inversion of the discharge states of its cells by selective activation of the pull-up and pull-down circuits whereby the resultant alternating sustainer voltage established across the cells for one set of applied substainer component wave forms defines an ''''off state'''' cell wall voltage level essentially at the cell wall voltage of a discharged cell in the ''''on state'''' cell wall voltage of a discharged cell for the one set of applied sustainer component wave forms is essentially at the off state cell wall voltage level for the second set of applied sustainer components. Signals for selectively manipulating the discharge state of each cell are applied to the electrodes of the cell by address pulsers comprising pull-to-ground circuits each of which functions for at least one electrode in each array. Pre-address pulsers reduce the bus potentials to minimize the power requirements on the address pulsers. Buss potential sensing circuits enable addressing of cells only when predetermined buss potentials are achieved. Circuits are provided to compensate for interconductor capacitance effects in the panel.

Implantable heart pacer or the like with internal cell electrode

Abstract: An implantable heart pacer comprising electrode means of dissimilar materials spaced from one another to provide an electrolyte-containing space therebetween for cooperating with an electrolyte therein to produce a cell voltage, being in communication with the exterior of said device. One of the electrode means has its surface exposed only to the electrolytecontaining space and is free from exposure on an external surface of said device to prevent direct contact with body tissues. A sealed electronic pulse unit provides an output pulse of higher voltage than said cell voltage, said electrode means providing a power source for said unit and providing an indifferent electrode for return current flow from a remote unipolar heart electrode connected to the output pulse terminal. With an output pulse voltage greater than the cell voltage, there is reverse current flow in the electrode means during the pulse for electrolytically cleaning their surfaces.

Arrangement of electrodes on a display panel utilizing gas discharge

Abstract: A self-shift plasma display panel based on the surface discharge is disclosed. This plasma display panel has two electrode groups of shift electrodes and channel electrodes which are positioned so that the two types of electrodes cross at right angles on the same substrate facing a discharge space filled with gas capable of ionization. The shift electrodes are alternately connected to first and second buss at intervals of one electrode, and the channel electrodes are alternately connected to third and fourth buss at intervals of one electrode. The above-mentioned four buss are connected to a four phase alternating voltage source. A discharge spot produced between a shift electrode and a channel electrode is shifted along the channel electrode by means of the four phase alternating voltage applied to the four buss in order.

Detection of breaks in flexible elongate members

Abstract: In a method of detecting breaks in an insulated electric conductor or other flexible elongate member whose surface is of an insulating material capable of generating an electrostatic charge by friction with another surface, the member travels in the direction of its length past and in continuous contact with at least one electrode which is connected to earth or some other charge sink. The electrode (or each electrode) is conductive and of a material chosen to cause electrons to be transferred continuously in one direction between the electrode (or each electrode) and the surface of the member and electrons are caused to flow between the charge sink and the electrode (or each electrode) or vice versa; the current flowing between the electrode or electrodes and earth is continuously monitored, preferably using an amplifier connected across a resistor between the electrode or electrodes and the charge sink.

Method for measuring liquid level by electrical conductivity

Abstract: A method for measuring a liquid according to the conductivity principle employing three electrodes, having one electrode constantly submerged in the electrically conductive liquid; a second electrode serving as a measuring electrode and submerged partially in the liquid level; a third electrode serving as the control electrode for the first and second electrodes, wherein an electric resistance exists between the first and second electrode depending on the submerged depth and the specific conductivity of the liquid so that both resistance values result in partial voltage drops which are compared and indicated with each other by compensating the conductivity fluxuations, comprises the steps of measuring separately both partial voltage drops of said first and second electrodes; applying the partial voltage drop of the first electrode to a saw-tooth generator so that the amplitude of the saw-tooth voltage output is equal to the voltage drop of said first electrode in a given time span, and applying the saw-tooth output voltage and the partial voltage drop of the second electrode to a comparator so that at the output of the comparator, a rectangular pulse signal is obtained having its ratio of pulse width to pulse period equaling the submerged depth.

Analog inverter for use in charge transfer apparatus

Abstract: In charge transfer apparatus, an analog inverter comprises a charge storage medium to which are applied varying voltages through a plurality of electrodes, illustratively: a source electrode, a reference electrode and a collector electrode arranged in tandem. Between the source and reference electrodes there is a first control electrode and, in one embodiment, between the reference and collector electrodes there is a second control electrode and a signal electrode. With the electrical signal to be inverted connected to the signal electrode, analog inversion, a form of complementing function, occurs as follows: (1) during the first phase of the clock cycle, a voltage is applied to the first control electrode effective to cause a fixed amount of charge to be transferred from the source to a reference potential well established under the reference electrode; (2) during the second phase of the clock cycle, a voltage is applied to the second control electrode effective to increase the surface potential thereunder and to permit charge to be transferred into a potential well under the collector electrode; this charge establishes a new surface potential which, apart from an additive constant is equal to the inverted signal voltage. In other embodiments in which the analog signal is of a self-strobing type (e.g., the output of a C4D or BB) the second control electrode is not required.

Self-biased development electrode and reproducing machine employing same

Abstract: A development apparatus for developing electrostatic charge patterns or images or a dielectric surface which includes an electrically biased development electrode in close proximity to the surface. The electrode is connected to ground potential through an impedance path which comprises at least one reversed biased zener diode. The electrode is self-biased with the biasing potential being a function of the breakdown voltage of the zener diode. The breakdown voltage of the diode is selected to give the desired electrode potential. Preferably, the apparatus includes means for changing the bias potential on the electrode. An electrostatographic reproducing apparatus employing the aforenoted developer apparatus is also claimed.

Electrolytic plating thickness measurement - by electrode array current density adjusted to that in bath comparing layer thickness

Abstract: The layer thickness of a coating deposited on workpiece in electrolytic baths is measured continuously and during the plating process by arranging in the bath liquid a concentric or parallel electrode system. Its current density is adjusted to suit that in the bath and the layer thickness on one of the electrodes is measured, compared with the desired value, and indicated or used to stop the process. This provides a very accurate measurement of the current layer thickness which is suitable for an automatic control of the plating operation.

Thermal switching in thin glass films triggered by a control electrode

Abstract: A new three‐electrode glass switch device is described that shows performance like a thyrister. The planar electrodes are obtained by dividing a chromium layer by two perpendicular gaps in four parts. Two of these parts are connected and form the common electrode. The two remaining parts are used as control electrode and load electrode. The device is in the on state, if the load electrode is connected by a conducting filament to the common electrode. Investigations of the performance of the new device show that the load diode can be triggered by a voltage pulse supplied to the control electrode if the control diode is in the off state. It can also be triggered by a current pulse supplied to the control electrode, if the control diode is in the on state and operated by a dc current. The measured performance of the new device is explained under the assumption that in both diodes a thermal‐switching mechanism takes place.

Self-compensated amplifier circuit

Abstract: A self-compensated semiconductor amplifier operable over the voltage range of a one cell battery and having an output voltage which varies inversely with the voltage applied by the one cell battery. The amplifier has a first transistor including base, emitter and collector electrodes. First and second resistors are serially connected from the collector electrode to the one cell battery. The base electrode is coupled to the junction of the first and second series connected resistors to provide a bias voltage at the base electrode, and for maintaining a constant voltage at the junction of the two resistors. The emitter electrode is coupled to ground potential. An output circuit is coupled to the collector electrode, and the collector electrode develops an output voltage thereat which is less than the bias voltage at the base electrode, and which varies inversely with the one cell battery voltage.

Time lag relay with a short recovery time

Abstract: An arrangement for achieving a short recovery time in a time lag relay, composed of static components in which the delay is determined by the charging time of a capacitor, includes two programmable unijunction transistors with the anode-cathode path in parallel with the capacitor and the control electrodes connected each to one voltage divider between the poles of the feeding voltage source. The voltage dividers are so designed and the control electrodes so connected to their voltage dividers that, during the charging of the capacitor, the voltage on the control electrode of the first transistor is higher than the voltage on the control electrode of the second transistor. If the charging process is interrupted before the relay has operated, the voltage on the control electrode of the first transistor falls more quickly than the voltage on the control electrode of the second transistor.

Electric field distributions and space charge behavior in nitrobenzene under low frequency alternating voltage

Abstract: It has been shown that the electric field distribution and, consequently, the space charge distribution, in a liqUid insulant are different under direct and low frequency alternating voltage and that both differ from ideal distribution predictable from geometry. It has been recently shown that in commercial insulating liquids the breakdown is controlled by space charge.2 For lack of more substantial information, however, authors7 have obtained the breakdown field strength at 60 Hz in an insulating liqUid by measuring the breakdown voltage and calculating field from the electrode geometry. It is shown here that even with plane parallel electrodes the field can differ markedly from the ideal case because the electric field in a liqUid insulator is defined by both the electrode geometry and by the space charge dynamics within the fluid.

Gas filled measuring condenser

Abstract: A condenser, especially for measurement purposes, in which the high voltage electrode and the low voltage electrode are arranged on the inside of an insulating casing housing filled with a gas; the space between the high voltage electrode and the low voltage electrode or a space enclosed by an auxiliary electrode surrounding the high voltage and low voltage electrodes is closed off insulatingly gas-tight and the pressure of the gas in this space is higher than the pressure of the gas in the space formed between such electrodes and the insulating casing housing.

Low-voltage starting means for arc lamp

Abstract: A low-voltage power supply can be used to start a gas-filled arc lamp having a movable electrode. To initiate the arc, a solenoid is energized by the low-voltage power supply to drive the movable electrode into contact with another electrode. An inductor is provided in series with the movable electrode. When the solenoid is deenergized, the movable electrode withdraws from contact with the other electrode, and a voltage which is larger than that of the power supply develops across the two electrodes. This difference of potential is attributable to the energy stored in the inductor, and is sufficient to ionize the gas in the gap between the two electrodes. In one embodiment the movable electrode is retractable into an anode electrode structure from which it is electrically insulated. The arc generated in the gap follows the movable electrode until the movable electrode is withdrawn into the anode structure, whereupon the arc jumps to the anode.

Voltage regulator with saturation protection

Abstract: A voltage regulator having a series regulator transistor with a potential threshold device for preventing saturation. The potential threshold device includes a voltage divider and diode connected between the input electrode and a control device connected to the control electrode of the series regulator transistor whereby a control voltage applied to the control electrode is decreased when the potential difference between the input and control electrodes decreases below a threshold level. A pincushion correction waveform is also applied to the control electrode to modulate the regulated voltage with a pincushion correction signal.