Abstract: A lighting device for a display device includes a plurality of light sources, a power source arranged to provide drive power for the light sources, a common electrode arranged to supply the drive power to the plurality of light sources, a plurality of holder electrodes arranged to hold the respective light sources and supply the drive power from the common electrode individually to the respective light sources, and a dielectric portion provided between the common electrode and each of the holder electrodes.

Abstract: Systems and methods for ignition and reignition of unstable electrical discharges wherein a secondary electrode positioned is between a set of primary electrodes and a high voltage is applied between the secondary electrode and successive ones of the primary electrodes to produce pilot discharges that ionize a gas there between and thereby reduce the voltage necessary to ignite a primary discharge between the primary electrodes. Power is provided to the secondary electrode by a circuit which is independent of the circuit that supplies power to the primary electrodes and generates voltage pulses which are substantially higher than the voltage between the primary electrodes.

Abstract: Systems and methods for ignition and reignition of unstable electrical discharges wherein a secondary electrode positioned is between a set of primary electrodes and a high voltage is applied between the secondary electrode and successive ones of the primary electrodes to produce pilot discharges that ionize a gas there between and thereby reduce the voltage necessary to ignite a primary discharge between the primary electrodes. Power is provided to the secondary electrode by a circuit which is independent of the circuit that supplies power to the primary electrodes and generates voltage pulses which are substantially higher than the voltage between the primary electrodes.

Abstract: A discharge lamp device which drives a discharge tube filled with a rare gas and has a first electrode mounted at the inside of the tube and a second electrode mounted at the outside of the tube. The lamp device includes a driving circuit that applies a voltage between the first and second electrodes. The driving circuit applies a positive rectangular wave voltage to the first electrode with a potential of the second electrode being a reference potential (0V) A backlight includes at least one discharge tube and the discharge lamp device.

Abstract: A discharge lamp which eliminates the large line noise that forms in discharge lamps during startup while preventing heat loss in the transformer by providing a pair of opposed electrodes for the main discharge and an auxiliary electrode arranged such that it does not come into contact with the discharge space for the main discharge, a feed circuit for supplying the discharge current to the electrodes for the main discharge, and a starter circuit which produces a high voltage between one of the electrodes for the main discharge and the auxiliary electrode. The high voltage generating part of the starter circuit which includes at least a high voltage transformer that is separated from the feed circuit while the discharge lamp and the high voltage generating part are formed as an integral unit.

Abstract: An auxiliary antenna arranged around the discharge vessel of a gas discharge lamp comprising an outer bulb enclosing this discharge vessel is provided on the outer bulb. The advantages of an auxiliary start antenna can thus be enjoyed without being counterbalanced by an increased sodium diffusion.

Abstract: Light source device which includes a discharge lamp which contains at least 0.15 mg mercury per cubic millimeter of the volume of the discharge space, a pair of electrodes opposite one another to create the main discharge and spaced a distance from one another of less than or equal to 2.5 mm, and an auxiliary electrode arranged such that it does not come into contact with the discharge space for the main discharge. The light source device further including a feed circuit to feed the discharge current to the electrodes for the main discharge, and a starter which produces a high voltage between one of the electrodes of the two electrodes for the main discharge and the auxiliary discharge, such that the starter produces a voltage two to five times as high as the voltage necessary for starting the main discharge in the lamp at the room temperature state.

Abstract: In a flash lamp, a mirror structure (20, 30, 40) is fixed at an inner end portion of an exhaust pipe (21, 34, 44) secured to a center of a stem (6) disposed at a bottom portion of an envelope (H). An arc emission part (S) is located at a focal position of a rounded mirror surface 24.

Abstract: In order to uniformly neutralize a large current and a large diameter ion beam so as to irradiate an ion beam having a reduced beam divergence on a process target, an ion beam processing apparatus comprises an ion source for producing a processing plasma, a processing chamber as a vacuum chamber for accommodating a process target, an extract electrode for extracting an ion beam so as to irradiate on said process target, an annular electrode disposed in said processing chamber for forming an annular magnetic field therein, through which said ion beam is irradiated on said process, and a wave guide for introducing microwave through an opening provided on a wall forming said processing chamber, into said annular magnetic field.

Abstract: A flash illumination system is provided which is especially useful for high-speed photography. In one embodiment, the invention provides a surface discharge lamp which produces an intense broadband burst of light having an intended spectrum. Another embodiment of the invention provides a surface discharge lamp which produces multiple pulses of intense broadband illumination at very high pulse repetition rates. The lamp in either embodiment is fabricated in a relatively inexpensive manner and can be compactly constructed and of modular construction to suit various applications. The lamp is composed of a gas envelope in which is provided a dielectric substrate and electrodes at respective ends of a surface of the substrate. The substrate is preferably a portion of the enclosure. A backplane is disposed outside the enclosure and confronting the opposite surface of the substrate between the electrodes.

Abstract: A metal halide lamp, having a cold fill pressure of at least 50 torr, incorporates a starter circuit with an active device to protect the diode included therein. The active portion of the starter circuit, either removes a voltage multiplying circuit portion, from the starter circuit or shorts out the diode by shunting action of the switch. The voltage multiplier circuit portion is connected across the main electrodes, wherein the voltage multiplier circuit portion increases the starting voltage applied to the starter electrode.

Abstract: A switch for switching large currents and large charges includes an anode separated from a cathode with a cylindrical trigger electrode located around the anode and the gap. The cathode is of a metal such as zinc, cadmium, tin or magnesium. During operation, a suitable potential applied to the trigger electrode causes a main discharge to occur between the anode and the cathode.

Abstract: A discharge lamp lighting device according to the present invention includes: a discharge lamp including an electrode; and a lighting circuit for lighting the discharge lamp, the lighting circuit being connected to the discharge lamp, wherein the discharge lamp includes a conductor at least partially surrounding the electrode, and the lighting circuit provides a potential for the conductor that is higher than an average potential of the electrode.

Abstract: A high intensity discharge lamp includes a dielectric substrate, a first electrode near the dielectric substrate, a second electrode spaced from the first electrode and near the dielectric substrate, a conductor spaced from the dielectric substrate, and adapted to provide a current return from one of said electrodes to an electrical driver circuit, and at least one metal element near the dielectric substrate. The electrical driver circuit is constructed to produce an electric potential sufficient to cause an electrical breakdown of a medium between the electrodes. The lamp and metal element are also arranged to enable a coolant to flow adjacent to at least one surface of the dielectric substrate to transfer heat from the dielectric substrate to the coolant.

Abstract: An apparatus is provided for controlling the luminous output of a fluorescent lamp over a wide dimming range. The luminous output is controlled by controlling the lamp current, while the lamp is immersed in a lateral electrostatic field. The lamp and external electrostatic ionization electrodes are driven by a true analog voltage-to-current converter that has a dynamic range inherently wider than conventional PWM circuits. A modified, transformer coupled, push-pull converter with an analog-current-driven primary circuit is used in one embodiment of the apparatus. The lamp driver must be capable of providing a high compliance voltage consistent with the I-V profile of the lamp. A subordinate primary winding on the transformer may be used to reduce magnetization current and to supply sufficient energy for supporting the lateral electrostatic field that is generated by the ionization electrodes which may be printed on a PWB mounted behind the lamp.

Abstract: An improved gas discharge trigger for a pseudogap cold cathode thyratron. Electrical trigger pulses are capacitively coupled through the vacuum envelope wall (16) causing a gas discharge adjacent to the rear of the hollow cathode (26). Coupling apertures (12) between the trigger discharge region and the hollow cathode allow ionization to propagate into the rear of the hollow cathode and trigger the pseudogap from a non conducting to conducting state.

Abstract: A high intensity discharge lamp system includes an AC supply for a chamber within which a plasma conductor is created to generate light. In order to confine charged particles within the chamber and to inhibit migration and loss thereof, a DC circuit taps power from the AC supply and produces a DC potential which is applied to relatively large-surface components in the vicinity of the plasma chamber. Properly polarized, the large-surface components, such as a reflector and a conductive housing, refractor or door, produces electric fields which inhibit migration of the charged particles. The result is improved color and light output as well as increased lamp life.

Abstract: A high intensity discharge lamp system includes an AC supply for a chamber within which a plasma conductor is created to generate light. In order to control the concentrations of charged particles within the chamber and to influence migration thereof, a DC circuit taps power from the AC supply and produces a DC potential which is applied to relatively large-surface components in the vicinity of the plasma chamber. Properly polarized, the large-surface components, such as a reflector and a conductive housing, refractor or door, produces electric fields which either inhibit or encourage migration of the charged particles.

Abstract: A gas-discharge switch with a cold-cathode low-pressure gas discharge between the cathode and the anode has a discharge gap in a central discharge region of a discharge chamber. The maximum inside height of the discharge chamber determines the length of the discharge gap. In the discharge region, the inner surface of the discharge chamber is closed. Outside of the discharge region, the cathode is provided with at least one opening. This results in a gas-discharge switch with a short delay, low jitter and little voltage dependence with constant pressure.

Abstract: A gaseous-discharge lamp has a valve defining an interior of the lamp in which an inert gas, such as xenon, is confined. A cup-shaped reflector is disposed in the interior of the lamp, whose inner surface cross-section is preferably a hyperbola or an ellipse so that a collimated light spot is projected outwardly of the lamp or a focused light beam is available. The reflector has a larger-diameter opening facing a light projection window formed on one face of the valve and a bottom portion formed with a hole. An anode and a cathode are disposed in confrontation with each other in a space surrounded by the reflector. A trigger probe electrode intervenes between the anode and the cathode. A sparker electrode is disposed outside of the reflector and in the vicinity of the hole formed in the bottom portion thereof. By the provision of the reflector in the interior of the lamp, light of high radiation intensity is produced from the lamp without increasing the size of the lamp.

Abstract: A charging method within a glass tube using a direct current of low voltage is provided in order to obtain a small fluorescent lamp with a light emission of high luminance. Two distinct discharges are achieved through use of one negative electrode. The filament-like negative electrode is arranged at a short spaced relation to a positive electrode at one end of the glass tube and upon application of the direct current voltage becomes the preliminary discharge. A second positive electrode is positioned at the opposite end of the glass tube and has a greater-spaced relation to the negative electrode resulting in the second discharge.

Abstract: A cold-cathode discharge lamp device including a cold-cathode discharge lamp unit and a supplemental light source for emitting light toward a discharge space between a pair of cold-electrodes of the discharge lamp unit for producing initial electrons in the discharge space.

Abstract: The present invention concerns a method for triggering certain high voltage electronic, gas discharge switches that are a novel type of high power thyratron. In this invention, triggering of switches of the so-called "pseudospark thyratron" type (a type of cold cathode thyratron) is enhanced by the inclusion of a very small, hot thermiionic trigger switch or cathode, separate and isolated from the main switch electrodes, to initiate the triggering discharge. The trigger cathode is protected from destruction by the main discharge current through the switch by mechanically and electrically isolating it from further participation in the discharge once the triggering process has been initiated.

Abstract: The present invention encompasses a high voltage switch utilizing first and second terminal electrodes and an intermediate electrode disposed therebetween. A high voltage pulse, applied to the intermediate electrode, initiates sequential overvoltaging of the region between one of the terminal electrodes and the intermediate electrode and, then between the intermediate electrode and the other electrode; thereby permitting electrical current to flow between the terminal electrodes. The geometry of the electrodes is chosen so as to yield a field enhancement factor between each region which is sufficiently low to permit highly reliable, predictable, and controllable sequential electrical breakdown.

Abstract: A rare gas discharge lamp device comprises a bulb with a rare gas sealed therein, a pair of internal electrodes provided within the bulb, a phosphor layer formed on the inner surface of the bulb, a lighting circuit adapted to apply voltage across two internal electrodes to produce a discharge or a positive column between the internal electrodes, and an auxiliary electrode formed on the outer surface of the bulb and extending in the longitudinal direction of the bulb, the positive column being attracted toward the auxiliary electrode, and a window formed on the bulb in a manner to face the auxiliary electrode for emitting visible light to be produced within the bulb.

Abstract: An orientation independent ignitron (OII) has an anode, a cathode with a plurality of spaced grooves facing the anode, and a cooling mechanism which causes liquid metal vapor to condense as a film which is retained on the grooved cathode surface by surface tension and forms reservoirs within the grooves. The cathode and anode are preferably cylindrical and coaxial, with the inner surface of the cathode having parallel annular grooves facing the outer anode surface. Igniters are preferably introduced into convex areas between adjacent grooves along radial lines, with individual igniters providing ignition for a pair of adjacent grooves. The igniters can be operated simultaneously or in sequence, depending upon the desired repetition rate and current capacity. A liquid metal film is initially formed by placing the OII on its side, introducing liquid metal into the lower ends of the grooves, and causing arcing between the anode and liquid metal to flow the liquid metal and wet the adjacent groove surface.

Abstract: A deuterium lamp starting circuit utilizing the arc-defining aperture cage of the lamp as the arc-starting electrode to enable the application of a positive, low starting voltage simultaneously with the application of the filament voltage. This positive, low starting voltage is applied to the cage which operates as a starting electrode. After the anode to cathode arc strikes and the anode voltage decreases below the cutoff level, current between the cage and the cathode is reduced and the current flows between the cathode and the anode of the tube.

Abstract: A rare gas discharge lamp device comprises a bulb with a rare gas sealed therein, a pair of internal electrodes provided within the bulb, a phosphor layer formed on the inner surface of the bulb, a lighting circuit adapted to apply voltage across two internal electrodes to produce a discharge or a positive column between the internal electrodes, and an auxiliary electrode formed on the outer surface of the bulb and extending in the longitudinal direction of the bulb, the positive column being attracted toward the auxiliary electrode, and a window formed on the bulb in a manner to face the auxiliary electrode for emitting visible light to be produced within the bulb.

Abstract: A panoramic light emitter of an omnidirectional horizontal light beam with very sharp cut-off in the vertical plane is disclosed. The sharp cut-off prevents interference near airports. High average powers are attainable because the light source can be distributed rather than be a point source. The omnidirectional-in-the-horizontal-plane light emitter with a high degree of vertical beam control is achieved by combining a generally cylindrical refractor with an internally emitting open-ended generally conical light source. The internal emitting surface of the conical light source is in the focal plane of the cylindrical refractor. The refractor sharply images the source with its edges, and that image is projected panoramically as the light beam having sharp cut-off at the edges of the image. The external surface of the conical light source does not emit, thus preventing undesired angles of light from passing out through the refractor.

Abstract: In order to facilitate the initiation of plasma discharge inside a gaseous discharge tube, some form of pre-ionizing the gas is required. This invention describes a technique whereby a small but intense discharge region is created near the cathode of a d.c. discharge in order to generate the necessary electrons to initiate the formation of the main electrical discharge. It makes use of the high negative voltage that is applied on the discharge cathode with respect to the discharge anode. A third auxiliary pin electrode near the cathode is introduced into the discharge tube. It is connected on the outside to the anode through a resistor of a suitable value. In the presence of a high voltage across the main electrodes, corona discharge occurs near the auxiliary electrode. This leads to the formation of a small region of intense discharge between it and the cathode. The electron generated in this small discharge region would drift towards the anode under the high electric field between the main electrodes.

Abstract: The low pressure gas-filled thyratron is scalable in the long dimension. Internally the tube is formed as a tetrode, with an auxiliary grid placed between the cathode and the control grid. A DC or pulsed power source drives the auxiliary grid both to insure uniform cathode emission and to provide a grid-cathode plasma prior to commutation. The high voltage holdoff structure consists of the anode, the control grid and its electrostatic shielding baffles, and a main quartz insulator. A small gas flow supply and exhaust system is used that eliminates the need for a hydrogen reservoir and permits other gases, such as helium, to be used. The thyratron provides a low inductance, high current, long lifetime switch configuration; useful for switch-on applications involving large scale lasers and other similar loads that are distributed in a linear geometry.

Abstract: Disclosed is an electrical driving and recovery system for a high frequency environment. The recovery system can be applied to drive present day direct-current or alternating-current loads for better efficiency. It has a low-voltage source coupled to a vibrator, a transformer and a bridge-type rectifier to provide a high voltage pulsating signal to a first capacitor. Where a high-voltage source is otherwise available, it may be coupled directly to a bridge-type rectifier, causing a pulsating signal to the first capacitor. The first capacitor in turn is coupled to a high voltage anode of an electrical conversion switching element tube. The switching element tube also includes a low voltage anode which is connected to a voltage source by a commutator and a switching element tube. Mounted around the high voltage anode is a charge receiving plate which is coupled to an inductive load to transmit a high voltage discharge from the switching element tube to the load.

Abstract: A thyratron utilizable as a circuit interrupting protective device is provided. The thyratron includes an apertured grid between anode and cathode which is divided transversely into two parts separated by an insulating layer. Both surfaces of the composite grid remote from the insulating layer carry conductive meshes which meshes cover the exits of the apertures in the composite grid. The thickness of the insulating layer and the dimensions of the meshes are such that no point within an aperture is further from a part of the grid or a mesh than the Debye distance whereby the effects of Debye shielding tend to be reduced when a negative potential is applied between two said parts of said grid to quench a discharge previously initiated by applying positive potential to both parts of the grid.

Abstract: A high pressure metal vapor discharge lamp including an arc tube having at least a main electrode at each end thereof, a fill sealed in the arc tube, including mercury, metal halide and starting gases selected from the group consisting of Ar, Kr and Xe, a radioactive source material, impregnated with a radioactive substance having a half-life less than 1.times.10.sup.4 years, sealed in the arc tube and a circuit including a conventional low voltage mercury lamp ballast and a glow starter for starting the arc tube.

Abstract: A high intensity discharge (HID) lamp has an arc tube including a pair of main electrodes and at least one auxiliary electrode or probe, wherein a high frequency (HF) high voltage is applied to the probe for forming a high frequency (HF) ignition discharge for establishing a low frequency (LF) arc discharge between the main electrodes. In this ignition system, the electrodes of the arc tube are arranged so that an LF discharge path and an HF discharge path are positioned in an X- or a Y-configuration in the arc tube for causing easy lamp ignition. Also, to simplify the outer leads, it is desirable to mount the probe on one of the main electrodes by a dielectric member opposite another main electrode thereby to form a shorter gap between the probe and the other main electrodes than that between the main electrodes. The starting device of HID lamps has a high frequency-high voltage (HF-HV) generator, the output of which is applied, directly or indirectly, to the probe.

Abstract: A high pressure discharge lamp including discharge tube having at least two electrodes at opposite ends thereof, an outer bulb housing the discharge tube, a circuit for starting the discharge tube and a glow starter which is covered with a heat shield member and disposed between the discharge tube and the outer bulb.

Abstract: Discharge apparatus comprises a vacuum envelope which is evacuated by a pamping apparatus. In the envelope, an anode and a hollow cathode are disposed and are connected to an arc power supply. A disk having an orfice covers one end of the hollow cathode. A low pressure gas is supplied from a gas source to the envelope through the hollow cathode and the orifice, the gas pressure in the hollow cathode being maintained higher than that in the envelope. The hollow cathode and the disk are made of an electrically conductive material and are connected to an ignition power supply. Before effecting discharging between the anode and the hollow cathode, the ignition power supply causes an ignition between the disk and the inner surface of the hollow cathode.

Abstract: A single ended, low-wattage, high pressure, metal vapor discharge lamp includes first and second main electrodes and an auxiliary electrode resistively coupled to one of the main electrodes. The lamp provides a glow region remote from the main arc region and keeps wall blackening confined to areas remote from the main arc region. The lamp starts easier and minimizes detrimental glow time.

Abstract: A method for breaking direct current, whereby an initial gas pressure, corresponding to the working conditions of a stationary current channel, is set in a gas discharge device, whereafter direct current is passed through the gas discharge device, and the density of the gas filling said gas discharge device is simultaneously reduced over the entire volume of the gas discharge device to a critical value which causes a breaking of the direct current. The d.c. breaker for effecting this method is built around a gas discharge device comprising an anode, a cathode, and intermediate electrodes interposed between said anode and cathode. The cathode is formed by an end emitter, a cone-shaped reflector with the cone's apex facing the end emitter, and two coaxial cylinders encompassing the end emitter and reflector.

Abstract: A fluorescent lamp having a plurality of columns positioned in a generally uniform manner within the lamp envelope, each column having an electron emissive cathode mounted therein connected to a cathode leadwire. An anode member connected to an anode leadwire extends to the upper portions of each column. A conductive starter member is mounted within each column so as to provide a first gap between one of its ends and the cathode and a second gap between the other of its ends and the associated anode extension. A D.C. voltage is applied to the anode and cathode leadwires, the D.C. voltage being obtainable from an external A.C. source via a suitable voltage rectifier/multiplier circuit which is positioned within the re-entrant stem member of the lamp.

Abstract: A gas discharge lamp is connected across a step down auto transformer and in series with a solid state switching device and a resistor, and this combination is connected across a rectified AC voltage source. This switching device is controlled by a monostable multivibrator, the input of which is connected to the output of a comparator amplifier sensing the difference between the voltage drop across the above-mentioned resistor and a voltage which may be selected to vary light intensity. A starter aid conductor is placed adjacent the lamp and connected to the grounded side of the voltage source. This results in an efficient, high frequency operation of the lamp wherein the voltage gradient inside the lamp during starting ignition of the lamp is greatly increased to facilitate ignition despite the presence of the step down auto transformer, thereby permitting a decrease in the minimum fly back voltage necessary to start the lamp. As a result, reliability is increased.

Abstract: An in vacuo spark generator for the spectral analysis in the ultraviolet of a sample acting as an anode, with a coaxial annular cathode cooperating with the anode and an electrode for the formation of initiation sparks the operative portion of which is disposed opposite the outer side surface of the cathode and set back relative the frontal face of the cathode, the cathode frontal face being rounded and the opposite portions of the cathode and the initiation electrode being provided each with removable snap-rings slightly protruding relative to the body of the cathode and initiation electrode; said snap-rings are housed in a semicircular groove provided in the body of the cathode and the initiation electrode.

Abstract: The present invention relates to a method and apparatus for starting and maintaining a long electrical arc in an arc chamber containing a few atmospheres of pressure of an ionizable gas. An electrical potential difference is maintained between two fixed primary electrodes while a short arc is created between the first primary electrode and a pilot electrode, creating ionized gas. The ionized gas is caused to flow towards the second primary electrode thus creating a region of ionized gas between the two primary electrodes, and hence causing a long arc to be struck. This method does not require relative electrode movement as was the case previously.

Abstract: A triggered spark gap suitable for use with high levels of voltage and current over long periods of time generally comprising support means, a pair of insulated main electrodes disposed opposite each other on the support means so as to form a gap therebetween, first electrical means associated with the main electrodes for creating a potential difference therebetween, at least one trigger electrode defining a region having a cross-sectional thickness to width ratio greater than one, said trigger electrodes being mounted on the support means such that said region is disposed in the gap between the main electrodes, and second electrical means connecting the trigger electrode to a source of triggering and biasing potential.

Abstract: In a driving circuit which is used together with a flash lamp supplied with an exciting voltage and which comprises a transformer responsive to a trigger pulse for developing a pulse voltage and an exciting member around the lamp for causing a discharge to occur in the lamp in response to the pulse voltage to energize a laser device placed adjacent the lamp, a control member disposed between the transformer and the exciting member allows the pulse voltage to be applied across the lamp and suppresses a parasitic voltage which is otherwise developed across the transformer as a result of the discharge. The control member may comprise an air gap that is preferably from one to several millimeters long.

Abstract: A multiflash system including an arc discharge flashlamp having an elongated tubular envelope and containing three electrodes. A direct current voltage source comprising a large storage bank with positive and negative terminals is connected across two of the electrodes, and a storage capacitor is connected between the third electrode and the negative terminal of the source. The capacitor-connected electrode defines a first arc path with the electrode connected to the positive terminal of the source and a second arc path with the electrode connected to the negative terminal of the source. Trigger pulses are applied to the lamp so as to alternately energize the first and second arc paths, the storage capacitor being charged when the first arc path is energized to flash and discharged when the second arc path is energized to flash.

Abstract: An RLC triggering circuit employs an inductance coupled to the trigger electrode of a triggered vacuum gap device. A capacitance and a switch are coupled in series with the inductance. A diode in parallel with the series-coupled capacitance and switch serves to provide a long, unidirectional current pulse to prevent the triggered vacuum gap from chopping current and generating dangerous surge voltages.

Abstract: A high voltage interrupter consists of a cathode disposed centrally along the axis of an annular anode ring. The anode ring is a part of the wall of an evacuated container and is enclosed by a magnetic coil. Current flows through an arc plasma struck between the cathode and anode and this arc current is controlled by a magnetic field produced by the external coil which varies the impedance of the arc and causes the arc to extinguish. The anode contains a plurality of parallel metal vanes which extend into the interior of the evacuated housing to increase the current capability of the device and to control the rate of change of the current during switching operation.

Abstract: A circuit arrangement for triggering an arc discharge flash lamp that is directly coupled through series circuitry across an alternating current (AC) source. The lamp is ignited by a high voltage pulse generated from a pulse transformer in response to discharge of a voltage doubler charging capacitor by a controlled switch trigger from an RC timing circuit at a predetermined phase of the alternating current power source. Circuit operation is initiated by a switching arrangement which is coupled to the timing circuit through a zero crossing detector and shunt switch for assuring that the timing circuit starts at a predetermined point on the alternating current waveform. In this manner, the lamp reliably flashes with the same intensity each time a flash is requested.

Abstract: The invention relates to a starting and operating device, including an intance in the ignition circuit, for a high pressure discharge lamp, especially for a high pressure mercury vapor discharge lamp with metal halide additive, having at least one starting electrode positioned near one of the main electrodes within the discharge vessel. The starting electrode and the main electrode remote from the starting electrode are bridged by an electric circuit externally of the discharge vessel which comprises a current-interrupting and/or current-limiting electrical component. This arrangement of an auxiliary electrode within the discharge vessel of a high pressure discharge lamp brings about a reduction of the supply voltage required for initiation of the discharge which is particularly desirous in the case of high pressure mercury vapor discharge lamps containing metal halides.