Abstract: An adaptation circuit (3) for operating a high-pressure discharge lamp (1) via a controlled semiconductor switch (4) in series with the lamp. The control circuit for the switch (4) to comprise a voltage division circuit (5,6). The voltage division circuit is connected in parallel with the switch when the lamp is connected to the circuit output terminals (E,F) and one branch of the voltage division circuit comprises a parallel-combination of a capacitor (57) and a resistor (56). Thus, the variation of the voltage across the lamp influences the control of the semiconductor switch so that it is possible to stabilize, for the major part, the power dissipated by the lamp against, variation in the supply voltage and against lamp voltage variations during the life of the lamp.

Abstract: An improved high power (40,000 watt) high intensity arc discharge power supply which provides reliable, automatic ignition control and enables precise variation of lamp power in dual AC and DC modes of operation over an extended dynamic range from 400 watts to 40,000 watts. A capacitive boost circuit is provided to supply the high voltage necessary to ignite the lamp. Upon start-up, the voltage on a boost circuit capacitor is monitored by an ignition circuit which automatically enables the ignitor when the voltage is at the required level and switches the ignitor off when the lamp starts. After ignition the boost charging circuit is disabled and the power supply operates in a normal mode. The power supply operates on a three phase alternating voltage input through a three phase bridge, switches it through a drive transistor and then supplies it to an inductor. The signal is then supplied through an H-bridge commutator to the boost circuit, the ignitor and the arc lamp itself.

Abstract: A backup power system is provided for fluorescent lamps which energizes one of the lamps when normal A.C. mains power is not available. The circuit operates with a standard fluorescent fixture which contains two or more fluorescent lamps. When A.C. mains current is available, both lamps are operational so that the lighting fixture produces a maximum brightness. The A.C. mains current also trickle charges a low-voltage battery contained in the lighting fixture. When mains current is not available, the battery maintains only one of the lamps lighted. Consequently, although the lighting fixture produces a reduced output, the battery life is extended. In one embodiment both fluorescent lamps are powered directly from the AC line. When A.C. power is not available, a relay disconnects the A.C. line from both lamps and connects one lamp to a DC/AC inverter which is powered by the internal battery.

Abstract: A rapid restrike metal halide lamp and method of operating such a lamp are disclosed which are particularly suitable for sports stadium lighting applications. The rapid restrike metal halide lamp has an arc tube containing constituents which require a waveform having a relatively high voltage and at a relatively high current in order to rapidly restrike the arc tube after the lamp has experienced a power interruption so as to initiate a sustaining arc condition of the arc tube. The relatively high waveform in the form of a series of pulse trains is routed to the arc tube by means of a two path arrangement comprising a conductive base at the bottom of the lamp and a insulative cap at the top of the lamp. This two-way path substantially reduces and even eliminates any arcing condition within the confines of the lamp.

Abstract: A system of daylight running lights utilizing the front turn signal lights of a vehicle incorporates a solenoid coil and a double pole single throw switch, such that when the coil is activated, both poles are closed. A connection from the ignition circuit to the coil is such that when the ignition circuit is at "run", power is available to said coil. The circuit is such as to prevent the coil from being grounded, thus de-activating the coil, whenever the turn signal switch is on, or whenever the headlight switch is on. When either of these conditions applies, the DPST switch is open. The coil is grounded and thus activated whenever the turn signal switch and the headlight switch are both off. The circuit is such that power can be fed through the DPST switch, when closed, to energize both signal lights simultaneously, thus providing daytime running lights.

Abstract: A ballast circuit is provided for the start-up and operation of gaseous discharge lamps. A power transformer connected to an inductive/capacitive tank circuit drives the lamps from its secondary windings. An oscillator circuit generates a frequency modulated square wave output signal to vary the frequency of the power supplied to the tank circuit. A photodetector feedback circuit senses the light output of the lamps and regulates the frequency of the oscillator output signal. The feedback circuit also may provide input from a remote sensor or from an external computer controller. The feedback and oscillator circuits produce a high-frequency signal for lamp start-up and a lower, variable frequency signal for operating the lamps over a range of light intensity. The tank circuit is tuned to provide a sinusoidal signal to the lamps at its lowest operating frequency, which provides the greatest power to the lamps.

Abstract: A display device which is driven by a high driving voltage, has a display panel with display electrodes. A conductor line extends along the surface of the display panel. A high voltage producing means is connected to one end of the conductor line for applying a high voltage to the display electrodes. A low voltage source is connected to the other end of the conductor line for operating the high voltage producing means. Thus, an application of the high voltage to the display electrodes is terminated when the conductor line is broken or cut as a result of damage to the display panel.

Abstract: A solid-state ballast for discharge lamps includes a device for sensing the instantaneous current flowing within the load to produce illumination. A signal representing this load current is differentially processed with an external control signal representing the desired illumination, to produce an removed signal which controls an oscillator that provides the operating signal for the load. In addition, the voltage across the load is sensed and the signal representing this voltage is fed back to a circuit which controls the oscillator so as to limit the maximum load voltage during initial start-up and when a lamp is removed.

Abstract: An ion source for producing an ion beam utilized for fabrication and processing of semiconductors, thin films or the like includes a plasma producing chamber equipped with first magnetic means for limiting a plasma region and a plasma expansion chamber provided in combination with the plasma producing chamber on the side where a beam extracting electrode is disposed. The plasma expansion chamber is provided with second magnet array for confining and holding a plasma region therein which is of a larger area than that of the plasma region formed in the plasma producing chamber.

Abstract: The present invention is an improved decorative light set with clusters of light bulbs, an electric circuit and a d.c. power source for actuating the bulbs of clusters of the light bulbs and the electric circuit, wherein the circuit has two oscillators for producing pulses, a comparator for comparing the pulses of the two oscillators, a decoder actuated by the comparator. Random output signals are output by the decoding means for lighting the bulbs randomly as if the light set is sparkling and twinkling without using a long extending wire from a power source.

Abstract: A vehicle light control system for controlling the low beam of headlights of a vehicle. The system comprises a first and a second switching device with the first switching device being in a normally conductive state and the second device being in a normally non-conductive state. The first switching device is connected to the alternator of a vehicle to tap a supply voltage therefrom. The second conductive device is condition by the first conductive device and is also connected to a supply voltage to feed the low beams of the headlights when conditioned to do so by the first switching device. The headlight switch of the vehicle when switched on the high beams cuts off the first switching device and the supply voltage to the low beams. The supply voltage fed to the low beams is further reduced whereby not to subject the low beams to full intensity whereby to prolong their life span.

Abstract: A multipulse starting aid for a high-intensity discharge lamp includes a spiral line, a bi-directional solid-state switch, or a spark gap, coupled to one of the ends of the spiral line, a resistance in association with the spiral line to provide an RC time constant. The time constant RC is so adjusted that, upon receiving the alternating current voltage from the appropriate source, a waveform of voltage is presented across the pair of terminals of the lamp, together with the series of pulses at the peak of each half cycle of the waveform. thereby enhancing the lamp startability.

Abstract: A vehicle headlamp cleaning assembly and method for use in a vehicle includes cleaning means (27) which are energized when the headlamps (10) collect residue. The headlamp (10) includes a transparent lens (12), a light source (14) and a housing (16) with a reflective interior surface (18). The assembly includes sensing means (20) within the housing (16) which sense the light source radiation generated by the light source (14) sensed by a first sensor (22) and the backscattered light radiation reflected off residue on the exterior surface of the lens (12) sensed by a second sensor (24). A control circuit (26) compares the light source radiation and the backscattered light radiation. When the amount of backscattered light radiation has exceeded a predetermined magnitude, the cleaning means (27) is actuated.

Abstract: An array of indicator lamps is mounted on the rear of an automobile for signaling turns. When a turn is signaled, the lamps turn on in sequence, thereby creating the impression of motion in the desired direction. Each lamp is coupled to a battery via an associatd relay switch. A control circuit closes the relay switches in sequence, thereby turning on the lamps in sequence. The control circuit includes a set of flip-flops, each relay switch closing in response to an associated one of the flip-flops, which change state in response to a clock signal.

Abstract: An electric arrangement for regulating the luminous intensity of at least one discharge lamp (15). The arrangement comprises an electric circuit having a first winding (110) arranged to surround a core (111) of magnetizable material. The winding (110) is included in a circuit forming part of a DC/AC converter for the supply of high-frequency energy to the discharge lamp. The core (111) is further provided with a second winding (112) and a third winding (118). The third winding is connected to a control device forming part of the converter. The third winding is magnetically coupled to the first winding. A series-combination of a non-capacitive variable impedance (115) and a diode (113) is connected between the ends of the second winding.

Abstract: A circuit for operating low-pressure discharge lamps at elevated frequency comprises a reconnect circuit which disables the disconnect circuit upon exchange of a defective low-pressure discharge lamp (LP1). The disconnect circuit comprises a diode (D10), a resistor (R11) and a thyristor (TH) together with a trigger circuit (5). The reconnect circuit comprises a capacitor (C9) and a resistor (R12). Upon removal of the defective low-pressure discharge lamp (LP1), the capacitor (C9) is charged over the resistor (R12). Upon insertion of a new low-pressure discharge lamp (LP1), the capacitor (C9) is discharged and recharged in opposite direction and the holding current is removed from the thyristor (TH). This causes the thyristor (TH) to block, and enables the push-pull frequency generator (3) to start oscillating again.

Abstract: A flat matrix cathode-ray tube (CRT) in which the brightness of a display picture can be readily adjusted according to environmental brightness. In the flat matrix CRT, the grid electrodes are made up of the scanning electrodes and the data electrodes which form the matrix structure with the scanning electrodes, and the pulse voltage for gradations required are applied selectively to the scanning electrodes and the data electrodes so that the picture elements determined by the scanning electrodes and the data electrodes to which the pulse voltage are selectively applied are caused to emit light. Slots the number of which is determined in correspondence to the number of gradations selected, are provided either in the waveforms of the voltages applied to the scanning electrodes or in the waveforms of the voltages applied to the data electrodes in such a manner that the slots occur at regular intervals.

Abstract: A method of operating a high-pressure metal vapor discharge lamp at a periodic operating voltage of more than 500 Hz wherein the operating voltage is suddenly varied in phase at intervals, and preferably also wobbled in frequency, in order to avoid acoustic resonances in the lamp.

Abstract: A digital pulsewidth modulator switch regulator is used in a power supply for a multisection vacuum fluorescent display system. Pulsewidth modulations are based on grid and anode load characteristics of each section of the display, stored prior to system operations in a designated location of memory of a microcomputer used for controlling switching regulations. Display voltage updates are made utilizing the stored data as well as new load data derived from the power supply output voltage feedback signals indicative of changes in the display voltage.

Abstract: A liquid crystal matrix type multi-color display is provided incorporating transistor structure and wherein the display electrodes are energized from the transistor drain circuit in an electroplating both to coat and color the display electrodes.