Abstract: A gas discharge lamp is started with a high frequency AC signal from an oscillator and then operates on a low frequency AC signal provided by an AC to AC converter synchronously with the AC supply line. The low voltage switching devices of the converter are protected from the high voltages of the high frequency oscillator by locking the converter in a single phase during starting.

Abstract: Pulse stability is provided to a pulsed gas filled electrical discharge device by an electrical circuit including first and second electrical energy storage means, with the energy stored in the first storage means being substantially greater than the energy stored in the second storage means. A first voltage corresponding to the energy stored on the first storage means is applied to the input of the gas filled device. A second voltage corresponding to the energy stored on the second storage means is periodically switched to combine with the first voltage and be input to the gas filled device. The period for switching is precisely controlled, preferably with a piezoelectric crystal, and is selected to combine the first and second voltages just before the first voltage reaches the natural breakdown voltage of the gas within the gas filled device.

Abstract: A power supply circuit is disclosed for a ring laser having a cathode and having first and second anodes so that the ionization current between the cathode and each of the anodes are substantially equal. According to the invention, a Zener diode is electrically connected in the path of one of the ionization currents. The Zener voltage magnitude of the Zener diode is selected so as to equalize the ionization currents.

Abstract: There is disclosed an operating circuit for an electric discharge lamp in which a first DC operating circuit for starting an electric discharge lamp, a second DC operating circuit for making the electric discharge lamp operative by a voltage near a rated lamp voltage and by a current near a rated lamp current, and a third DC operating circuit for supplying a relatively large current to the electric discharge lamp immediately after the electric discharge lamp is started and for stabilizing the lamp luminous flux in a short time, are connected in parallel. A switching circuit for cutting off the first DC operating circuit after the electric discharge lamp is started is provided at the output terminal of the first DC operating circuit. In addition, reverse current preventing circuits for preventing the currents from reversely flowing from the operating circuits at higher voltages are provided at the output terminals of the second and third DC operating circuits.

Abstract: A power supply unit for electronic flash includes a plurality of charging units connected to a main capacitor of an electronic flash through diodes which prevent a reverse current flow. Each charging unit includes a d.c. source and a booster converter. An efficient utilization of the source battery is attained by reducing loading upon each source. The use of components of reduced capacity enables a reduction in the size of the overall unit. A single power switch enables a simultaneous initiation of the charging of the main capacitor by all of the charging units. When the main capacitor is charged to a given value, disable means are simultaneously operated in response to an output from charging voltage detecting means, thus simultaneously ceasing the charging operation of the charging units.

Abstract: A photographic flash device comprising a grip portion and a flash unit removably attachable thereto. Both the grip portion and flash unit house battery-powered DC-DC converters which cooperate upon attachment of the flash unit to the grip portion in charging a main discharge capacitor. A source switch permits charging of the discharge capacitor by only one of the DC-DC converters, and a safety switch prevents operation of at least one of the converters when the flash unit is not attached to the grip portion.

Abstract: An electronic ballast circuit for a lower pressure lamp wherein a voltage divider network coupled by a capacitor and directly coupled to an AC source is shunted by a series connected transistor switch and capacitor filter, and the switch is coupled by a diode to a lamp while a ballast resistor couples the filter capacitor to the lamp. A starter network device includes a glo-bottle starter which couples a transistor switch to the lamp with a resistor coupled to the glo-bottle starter and the transistor switch.

Abstract: In a circuit for the operating of gas discharge lamps in which a starting circuit (2, 17) having a starter transformer (17) and a source of auxiliary voltage which can be disconnected after starting has been effected are provided for the starting of the lamp, there is provided a full-wave rectifier (6) with which a charging capacitor (10) and a voltage-dependent electronic switch element (8) are connected in parallel. A switch contact (9) which is in series with the charging capacitor (10) can be actuated by the switch element (8). The charging capacitor (10) which supplies the operating voltage for the gas discharge lamp (3) can be charged to a voltage which can be selected by means of the switch element (8). The full-wave rectifier (6) which serves a source of auxiliary voltage can be disconnected by means of a control element (4) from the gas discharge lamp (3) after the latter has been started.

Abstract: An arrangement for the current limitation during the current supply of electrically excited gas lasers includes a rotary current transformer, self-inductances provided in front of a rotary current bridge rectifier, and a capacitor, if desired. In each phase conductor an inductance is provided between the secondary side of the rotary current transformer preferably working at power frequency and the rotary current bridge rectifier.

Abstract: A discharge lamp firing apparatus is disclosed which includes providing only the necessary firing voltage to the lamp prior to the firing thereof. As such, the surrounding system is not subjected to transients caused by conventional mechanisms which suddenly switch an extremely high voltage across the lamp. As a result, the present apparatus protects the associated circuitry as well as prevents needless overvoltage conditions to the lamp.

Abstract: An energy conserving lighting system is provided wherein a plurality of fluorescent lamps are powered by a poorly regulated voltage source power supply which provides a decreasing supply voltage with increasing arc current so as to generally match the volt-ampere characteristics of the lamps. A transistor ballast and control circuit connected in the arc current path controls the arc current, and hence the light output, in accordance with the total ambient light, i.e., the light produced by the lamps together with whatever further light is produced by other sources such as daylight. In another embodiment, a transistor ballast is utilized in combination with an inductive ballast. The transistor ballast provides current control over a wide dynamic range up to a design current maximum at which maximum the transistor is saturated and the inductive ballast takes over the current limiting function.

Abstract: An apparatus for a gaseous discharge lamp includes a power controlling device for converting an AC voltage into a phase control output, a high frequency generating device for converting the output of the high frequency generating device into an high frequency output and a discharge lamp which is lighted by the output of the high frequency generating device and whose filament is heated. The high frequency generating device includes a DC power source for supplying a DC voltage to the power controlling device whenever the power controlling device remains to generate the phase control output. The output of the DC power source heats the filament of the discharge lamp for a period during which no phase control output is produced.

Abstract: A low frequency AC voltage is rectified through a full-wave rectifier to obtain a pulsating voltage, which is superimposed with an auxiliary voltage of a predetermined level provided from an auxiliary power source, and the resultant composite pulsating voltage is inverted at an inverter to a high frequency voltage. The high frequency voltage thus obtained from the inverter is used to operate a discharge lamp. Minimum value V.sub.min of the resultant voltage is set to be 1/3 to 4/5 of the maximum value V.sub.max of the resultant voltage.

Abstract: A method and apparatus for producing gas discharge reactions in which a reaction gas is at least partially oxygenated after being taken through a discharge channel. In order to produce ozone by means of an electric discharge, the discharge channel has applied thereto an electric alternating voltage signal consisting of a sinusoidal potential (U.sub.a) with positive and negative peak values minimally below the firing potential of the discharge channel, and of alternating voltage impulses superimposed on the sinusoidal potential essentially at the respective maximum and minimum values, in order to achieve an exalted potential above the firing potential to enable a discharge reaction. An ozonizer implemented in this way is also disclosed.

Abstract: An ignition system (51-59, 60, Ql, Qn, 30) providing high modulation energy by means of modulator (30) is used to fire an igniter and effect total fuel burning without detonation. An extremely long ignition arc is initiated at an optimum timing angle (.theta..degree.) in advance of top dead center piston position. Such long arc with its high energy content makes possible an ignited fuel nodule of increased size within the combustion chamber of the engine. The increased fuel nodule size makes possible efficient engine operation at the variety of cylinder pressures and the variety of ignition voltages usable to ignite the fuel. These long arcs may be sustained over a large range of duty cycle periods of ignition electrical power by modulation of transient current feeding the igniter.

Abstract: There is disclosed herein an electronic flash system which obviates the need for the typical large capacity main capacitor as the power source for the flashtube. The system includes a conventional flashtube, trigger circuit for ionizing the flashtube and control circuit for turning on and off an electronic switching element which applies the main operating power to the flashtube. The ignition circuit for the flashtube uses a relatively small capacitor which is charged to a high voltage level for first igniting the flashtube and causing it to commence emission of light. Once ignited, a medium voltage power supply supplies the necessary current level for the required length of time to continue the production of the flash of light. The system also enables the use of a relatively small electronic switch as well as a relatively small voltage converter for charging the ignition capacitor.

Abstract: A solid-state ballast circuit for starting and regulating a gaseous discharge lamp which is operated on direct current is arranged so as to permit the use of low voltage switching relays to effect polarity reversal of the lamp under load. A high voltage pulse source is connected in series with the lamp and a low voltage switching relay is connected in a manner to effect polarity reversal of the DC voltage applied to the combination of the high voltage source and lamp. The voltage appearing across the high voltage source is prevented from reaching the switching relays by virtue of a bridge rectifier circuit connected such that the pulse source and lamp appear as a current source for the rectifiers. The output terminals of the bridge rectifier arrangement are connected between the output terminals of the low voltage DC source thus limiting the voltage applied to the switching relays to a value not exceeding that of the DC source.

Abstract: In an electronic photographic flash apparatus comprising a DC-DC converter, a high tension capacitor, and a gas-discharge flash tube to produce a light flash by consuming electric energy stored in said high tension capacitor,the improvement is that the apparatus further comprisinga low tension capacitor and a switching circuit which connects the low tension capacitor parallel to the DC low voltage source for charging therein at an off-state of the apparatus, and connects the low tension capacitor in series to the DC low voltage source in a subsequent stand-by period thereby to boost the operation of the DC-DC converter at an initial stage in the waiting time when the power switch is on, so as to quickly charge up the high tension capacitor.

Abstract: A strobe apparatus for reducing contrast index in photographic copies by employing an illumination pulse of short duration includes a source energizable at both a relatively high level to provide high intensity illumination and at a low level to provide low intensity illumination.

Abstract: An inductive-capacitive cyclic charge-discharge ignition system includes an ignition transformer primary winding in parallel with a capacitor and fed by an alternating current source providing a plural number of repetition cycles during each igniter firing period. Such repetition cycles cause the capacitor and primary winding to charge and discharge during each of the repetition cycles creating a plurality of ringing periods for each igniter firing period. A diode or an additional capacitor, or both, inserted in series with the parallel combination of the first stated capacitor and primary winding, substantially increases the velocity of arc provided by an igniter. Such arc has several components composed of luninous particles extending across the entire base of the igniter.

Abstract: Starting and operating power is provided to a gas discharge lamp by a circuit which includes a constant-voltage current-limiting ferroresonant transformer connected to an AC source and having high and low voltage output terminals. A full-wave rectifying bridge is selectively connectable to either the high or low voltage output terminals by relay control means which includes a choke coil connected in series with the lamp and a magnet reed. On starting of the lamp the magnetic flux of the choke coil operates the reed for shifting to the low voltage condition, and on extinguishing of the lamp the collapse of the choke coil flux operates the reed for shifting to the normal high voltage condition. A transient high voltage starting pulse is applied to the lamp across a spark gap by a pulse generating starting circuit in which a capacitor, charged from the DC output, is discharged through a self-commutating SCR and an ignition transformer.

Abstract: In an ignition circuit for a split section gas discharge laser having a common anode, a positive sustaining voltage is applied to the common anode while independent negative starting potentials are applied through high resistances to cathodes at either end of the laser tube which are grounded through diodes to prevent shorting of the ignition voltage source while providing a return path for the sustaining voltage source. The cathodes are immediately brought to ground potential upon ignition so that gas discharge in each of the two sections may be independently ignited while mirrors at either end of the laser tube are maintained at or near ground potential during operation of the laser after ignition.

Abstract: An energizing circuit for gas discharge lamps for room or street lighting or for lights used in document copying machines and the like comprises means for continuously energizing the same at a low non-useful light producing level when such lamps are not needed by a voltage which strikes an arc and maintains a low level of ionization with an infinitesimally small current and very little energy drain. This voltage may be an AC voltage or a DC voltage supplied by a unique circuit including a number of DC voltage sources, rectifiers, voltage adjusting and current-limiting impedances and electronic switches. The lamps are energized by AC or pulsating DC supplied by the aforesaid or other electronic switches operated at a high frequency of at least about 20-30 kilo-Hertz.

Abstract: An electronic flashlight apparatus comprising a flash tube filled with a noble or inert gas of a pressure greater than the atmospheric pressure and having main electrodes and a trigger electrode arranged to receive a triggering pulse from a trigger circuit, a storage capacitor arranged to be charged by a charging circuit through at least one diode and connected across the main electrodes of the flash tube, and an auxiliary capacitor having small capcitance as compared to the storage capacitor, the auxiliary capacitor being also connected across the main electrodes of the flash tube, and being arranged to be charged through a second charging circuit to a voltage which is larger than the charging voltage of the storage capacitor.

Abstract: The specification discloses an igniter circuit for extending the lifetime of a gas filled electric lamp. The igniter circuit includes a D.C. boost converter for generating an open circuit D.C. voltage for application to the lamp prior to ignition of the lamp. A resistance is initially connected between the converter and the lamp in order to limit the current applied to the lamp to a first predetermined level. A timer is connected to be energized concurrently with the D.C. boost converter in order to generate a timing signal after a predetermined time interval. A relay is responsive to the timing signal in order to establish a short circuit across the resistance in order to increase the current applied to the lamp to a second predetermined level higher than the first level. Current is not increased to the second predetermined level if the lamp ignites prior to generation of the timing signal.

Abstract: A high voltage power supply for a capacitive load switches between two different voltages of the same polarity relative to ground within about 15 microseconds and is useful as the switching supply for beam penetration cathode ray tubes in short range radar systems. The power supply comprises two power supplies of different voltages which are selectively connected to an output capacitive load. The lower voltage supply is connected directly to the load through a low voltage clamping diode. The higher voltage power supply is connected in series with an inductor, which is, in turn, connected to the load through an up-switch circuit which is closed to increase the power supply output voltage to an upper level and a down-switch circuit which is closed to reduce the power supply voltage to a lower level. Each switch consists of one or more transistors in series with a switching diode.

Abstract: A circuit having two modes of operation for driving either one of a light emitting diode or a gas discharge tube (digitron) display from a single semiconductor chip. Respective voltages are supplied to the chip to enable the circuit to selectively operate in either of the light emitting diode or digitron modes.

Abstract: A relatively infinitely incremental mode of obtaining any desired brightness of flash from an electrically operable flash-tube is attained by employing plural capacitors, each having a charging source of selectable voltage level and a unilaterally conductive element between the capacitor and the flash-tube. The unilaterally conductive element is poled to pass the charge on the associated capacitor during the discharge cycle regardless of the voltage of the charge on other of the plural capacitors involved.

Abstract: A self-triggering circuit for a gas-filled laser is disclosed. Electrical pulses which stimulate laser emission are applied to the laser cavity in response to an electrical energy change in the laser charging circuit when ionizing radiation is injected into the laser cavity. A semiconductor device of the type responsive to dv/dt, or of the type responsive to di/dt, is used as the self-triggering switch.

Abstract: A pulsed power supply for a gas discharge laser in which a main DC power supply is connected in series with a current limited DC power supply and a gas discharge laser and with diode means connected across the second power supply for bypassing the second power supply and conducting current from the main power supply to the laser after the laser ionizes.

Abstract: Color rendition of high pressure sodium vapor discharge lamps is improved by disclosed operating circuit for applying pulsed direct current to the lamp. The circuit includes a direct current ballast circuit having a low ripple factor, a filter capacitor charged by the output of the ballast circuit, and a pulsing circuit comprising a transistor switch which operates to apply DC pulses on the lamp at a predetermined repetition rate and duty cycle to provide desired color properties of the lamp.

Abstract: Increased color temperature of high pressure sodium vapor discharge lamps is provided by improved operating circuit for applying pulsed direct current to the lamp. The circuit includes a direct current ballast circuit having low ripple factor and a pulsing circuit comprising a controlled thyristor switch which operates to apply DC pulses to the lamp at a predetermined repetition rate and duty cycle. The described circuit provides for gradual increase in power applied to the discharge lamp during the starting interval and thereby avoids instability of lamp operation during that stage.

Abstract: Electrical ballast circuit for operating gaseous discharge lamps with direct current. An inductive reactor coil connected to an alternating current source is connected to a discharge lamp via a full-wave rectifier, and an auxiliary induction coil inductively coupled to the reactor coil is connected to the discharge lamp via another full-wave rectifier, resulting in the currents from the respective rectifiers to the lamp being out of phase with one another, thereby raising the average current through the lamp and the voltage across the lamp to prevent lamp de-ionization and reduce lamp re-ignition voltage. Series connected capacitors may be incorporated in the circuit to increase the starting voltage on the lamp if necessary.

Abstract: A high voltage glow discharge power source providing a plurality of glow discharges by gas ignition within at least one elongated electrically insulating member having a central bore along the axis of elongation of the member. Electrodes are positioned along the outer surface along the length of the member to which current sources and sinks are connected in alternation. A DC power supply provides the energy for the current sources and sinks. End plates covering the bore are transparent to optical frequencies. Glow discharges occur within the bore so that when a laser generator beam is diverted into the bore through the end plates, the gas in the bore being ignited to provide the glow, discharges and effects a power gain in the laser signal at the other end of the bore.

Abstract: The specification discloses a voltage supply system particularly adapted for use as an automatic brightness control for an image intensifier tube. The system includes a power oscillator for applying a constant A.C. voltage to a first multiplier which generates at least one constant D.C. voltage for application to the screen of the image intensifier tube. A regulator circuit includes a low power oscillator which generates a control A.C. signal and which further includes circuitry responsive to the screen current of the image intensifier tube for varying the amplitude of the control A.C. signal. The frequency of the control A.C. signal is substantially greater than the frequency of the constant A.C. voltage. A bilateral attenuator receives the constant A.C. voltage and is operable in response to the control A.C. signal for varying the amplitude of the constant A.C. voltage. A second multiplier is connected to the output of the attenuator for generating a variable D.C.

Abstract: The energizing circuit of one of the primary windings of an ignition coil having at least two primary windings and a secondary winding is interrupted in timed relationship with the engine whereby a high ignition arc-creating potential is induced in the secondary winding upon each interruption of the primary winding energizing circuit. Upon each interruption of the primary winding energizing circuit, a monostable multivibrator circuit is triggered to the alternate state in which a potential signal is present upon the output circuit thereof and an electrical switching device is triggered conductive to complete a discharge circuit for an ignition capacitor through the other ignition coil primary winding.