Abstract: A plasma generation apparatus, and a plasma thruster configured to use the plasma generation apparatus are disclosed. The plasma generation apparatus includes a discharge vessel, a light-emitting monitor, a probe measuring instrument, a control device, and an optical axis driving unit. The discharge vessel is configured to ionize gas which is introduced to an inside thereof so as to generate plasma. The light-emitting monitor is configured to measure electron density of the plasma by emission spectra of the plasma. The probe measuring instrument is configured to measure the electron density of the plasma by a probe in the discharge vessel.

Abstract: An autonomous method for minimizing the magnitude of plasma discharge current oscillations in a Hall effect plasma device includes iteratively measuring plasma discharge current oscillations of the plasma device and iteratively adjusting the magnet current delivered to the plasma device in response to measured plasma discharge current oscillations to reduce the magnitude of the plasma discharge current oscillations.

Abstract: An induction RF fluorescent lamp includes a lamp envelope with a re-entrant cavity both covered on a partial vacuum side with phosphor and filled with a working gas mixture; a power coupler on the non-vacuum side of said re-entrant cavity comprising a ferromagnetic core overwound with at least one turn of an electrical conductor; an electronic ballast, wherein the ballast converts mains frequency voltage and current to a power coupler frequency voltage and current, the electronic ballast providing the voltage and current to the power coupler through at least two of a plurality of electrical terminals of the electronic ballast; a capacitor electrically connected between the ferromagnetic core and at least one of the plurality of electrical terminals of the electronic ballast, wherein the magnitude of the impedance of the capacitor is high at the mains frequency and the magnitude of the impedance of that same capacitor is low at the operating frequency of the RF fluorescent lamp.

Abstract: The invention relates to a plasma source with an oscillator having an active element and a resonator connected to the active element. The resonator has a hollow body, a gas inlet, a gas outlet arranged at a distal end of the hollow body about a longitudinal axis of the hollow body, and a coil arranged along the longitudinal axis of the hollow body, said coil having an effective length of one quarter of a wavelength at a resonant frequency of the resonator. A distal end of the coil is arranged relative to the gas outlet such that a plasma section can form between the distal end of the coil serving as a first plasma electrode and the gas outlet of the hollow body serving as a second plasma electrode. At a proximal end of the hollow body, the coil is lead out of the interior of the hollow body through an electrically contact-free feed-through, and a proximal end of the coil contacts the hollow body at its external side.

Abstract: An induction RF fluorescent lamp configuration provides reduced EMI, including a lamp envelope with a re-entrant cavity both covered on the partial vacuum side with phosphor and filled with a working gas mixture, a tubular ferromagnetic core on the non-vacuum side said re-entrant cavity wound directly on the said core with two windings having different numbers of turns, a first active winding having one end connected to an RF ballast and the other end connected to local ground, and a second passive winding having one end grounded and the other end free.

Abstract: A lighting system comprising a lamp arranged to transform electricity into a light beam having properties such as intensity, color, color temperature, direction and beam cone angle; a light control means arranged to adjust said light beam properties; a plurality of ultrasonic transmitters arranged to transmit ultrasonic signals; a plurality of ultrasonic receivers arranged to receive reflected ultrasonic signals; and a processing means arranged to send an ultrasonic pulse sequentially through each of said transmitters and to determine after each pulse is sent which ones of said receivers receive a reflected ultrasonic signal with an amplitude exceeding a predetermined threshold within a predetermined period, and to send control signals to said light control means in dependence of said determination.

Abstract: A plasma lamp apparatus includes a post structure with a material overlying a surface region of the post structure, which has a first end and a second end. The apparatus also has a helical coil structure configured along the post structure. The apparatus includes a bulb with a fill material capable of emitting electromagnetic radiation. A resonator coupling element configured to feed radio frequency energy to at least the helical coil causes the bulb device to emit electromagnetic radiation.

Abstract: An autonomous method for minimizing the magnitude of plasma discharge current oscillations in a Hall effect plasma device includes iteratively measuring plasma discharge current oscillations of the plasma device and iteratively adjusting the magnet current delivered to the plasma device in response to measured plasma discharge current oscillations to reduce the magnitude of the plasma discharge current oscillations.

Abstract: A multi-column electron beam exposure apparatus includes: multiple column cells; an electron beam converging unit in which two annular permanent magnets and electromagnetic coils are surrounded by a ferromagnetic frame, the two annular permanent magnets being magnetized in an optical axis direction and symmetrical about the optical axis, where the electromagnetic coils adjust magnetic fields of the annular permanent magnets; and a substrate provided with circular apertures through which electron beams used in the column cells pass, respectively, where the electron beam converging unit is disposed in each of the circular apertures. The two annular permanent magnets may be disposed one above the other in the optical axis direction, and the electromagnetic coils may be provided inside or outside the annular permanent magnets in their radial direction.

Abstract: A lighting system comprising a lamp arranged to transform electricity into a light beam having properties including intensity, color, color temperature, direction and beam cone angle, a light control system arranged to adjust said light beam properties, an ultrasonic transmitter arranged to transmit ultrasonic signals, an ultrasonic receiver arranged to receive reflected ultrasonic signals, and a processing system arranged to derive a time-of-flight signal representing the time differences between said transmitted and received ultrasonic signals and to send control signals to said light control system in dependence of said time-of-flight signal, wherein said processing system is further arranged to perform a sound pressure level calibration step wherein the amplitude of the received reflected ultrasonic signal of the receiver is measured and wherein the amplitude of the transmitted ultrasonic signal of the transmitter is adjusted such that the amplitude of the received reflected signal approximates a predeter

Abstract: A lighting system comprising a lamp arranged to transform electricity into a light beam having properties such as intensity, lour, lour temperature, direction and beam cone angle, a light control system arranged to adjust said light beam properties, an ultrasonic transmitter arranged to transmit ultrasonic signals, an ultrasonic receiver arranged to receive reflected ultrasonic signals, and a processing system arranged to derive a time-of-flight signal representing the time differences between said transmitted and received ultrasonic signals and to send control signals to said light control system in dependence of said time-of-flight signal.

Abstract: A lighting system comprising a lamp arranged to transform electricity into a light beam having different properties; a light control system arranged to adjust said light beam properties; an ultrasonic transmitter arranged to transmit ultrasonic signals; an ultrasonic receiver arranged to receive reflected ultrasonic signals; and a processing system arranged to derive a time-of-flight signal representing the time differences between said transmitted and received ultrasonic signals and to send control signals to said light control system in dependence of said time-of-flight signal. The processing system performs a reference calibration step: the time-of-flight is repeatedly measured a multitude of times, and calculates the average of said measured time-of-flight values and stores the average in memory system as a reference time-of-flight value if said deviation of the majority of the measured time-of-flight values of said multitude of measurements is lower than a predetermined threshold.

Abstract: A lighting system comprising a lamp comprising an array of LEDs arranged to transform electricity into a light beam having properties including intensity, color, color temperature; a fight control system comprising a LED driver and a pulse width modulator arranged to adjust said light beam properties; a DA-converter, an ultrasound driver and an ultrasonic transmitter arranged to convert a digital transmit signal into the transmission of an ultrasonic pulse; an ultrasonic receiver and an amplifier arranged to receive reflected ultrasonic signals and transform said ultrasonic signal in a voltage, and a comparator arranged to generate a digital receive signal if said voltage is greater than a predetermined threshold; a processing system arranged to derive a time-of-flight signal representing the time differences between said digital transmit and receive signals and to send control signals to said light control system in dependence of said time-of-flight signal.

Abstract: An electrodeless discharge lamp device comprises an induction coil, a pair of cores 1a, 1b, and thermal conductor 2. The cores 1a, 1b are configured to generate a high-frequency electromagnetic field for exciting a discharge gas with receiving a high frequency electric power. Each of the cores is arranged to give an overall circumference around which the induction coil is wound. The thermal conductor is formed into an approximately cylindrical shape and inserted into the space so as to be thermally coupled with the cores for radiating heat generated at the cores. The core has its inside face at least center portion of which is spaced radially from the thermal conductor by a predetermined distance.

Abstract: A discharge lamp lighting apparatus includes: an inverter circuit including a switch circuit and a high-voltage transformer; a step-up circuit connected at the input stage of the inverter circuit; a control circuit to output a switch circuit controlling signal and a step-up circuit controlling signal; an on-off switching circuit connected at a input voltage line; and a switch signal buffering circuit connected between the control circuit and the switch circuit and adapted to relay the switch circuit controlling signal. A drive voltage is applied to the control circuit without going through the on-off switching circuit, and a drive voltage is applied to the switch signal buffering circuit via the on-off switching circuit. With such a structure, an excess rush current is inhibited from flowing into the discharge lamp thereby preventing its electrode wear and therefore increasing the product life of a lamp and enhancing reliability while achieving cost reduction and downsizing.

Abstract: An electrodeless lighting apparatus using microwave and a method for controlling its power can lengthen lifetimes of the magnetron by constantly maintaining power applied to a magnetron of the electrodeless lighting apparatus using microwave. Therefore, when inputted AC voltage is changed, and thus oscillation current applied to a filament of the magnetron is changed, a rate of variability of voltage of the inputted AC power is compensated so that voltage and current applied to the magnetron is constantly maintained.

Abstract: An electrode-less fluorescent lamp and a method for manufacturing the same are disclosed. The electrode-less fluorescent lamp includes a closed-loop tubular discharge tube enclosing a discharge gas. The tube is coated with a fluorescent layer on an inner surface and is made of a light-transmissive material. The lamp also includes at least one core surrounding at least a portion of the discharge tube. The lamp includes at least one coil wound around the at least one core. The coil supplies electromagnetic power to the discharge tube by producing a time-varying magnetic field in the core. In addition, the lamp includes a radio frequency (RF) power source supplying RF power to the coil so that discharge generated in the discharge tube is maintained by said RF power.

Abstract: An apparatus for blocking ambient air of an electrodeless lighting system comprises: a waveguide including a shaft hole so that a bulb shaft can be penetrated therethrough; a bulb motor mounted on a rear side of the waveguide and connected to a bulb, which is located on a front side of the waveguide, using the bulb shaft for rotating the bulb; and a sealing unit installed between the bulb motor and the waveguide for blocking inflow of ambient air to a direction of the bulb, that is, a sealing structure can be ensured so that the ambient air is not flowed into the light emitting area where the mesh screen is located, and thereby impurities are not flowed into the light emitting area to ensure the clear light emitting conditions, the oxidization of mesh screen can be reduced, and the stability of the lighting apparatus is improved and maintenance cost can be reduced.

Abstract: A lamp assembly in accordance with the invention includes an electrodeless bulb (14) which is symmetrical about an axis (16) and which contains a light emissive fill which emits light when the bulb is excited by a RF electrical field coupled to the fill; an electrically conductive coupler (18) comprising a plurality of turns (20) which are symmetrical about an axis of the electrically conductive coupler, the turns defining a volume (19) that at least partially contains the bulb; and a conductor (26) connected to a center portion of the electrically conductive coupler with connection of the conductor to the electrically conductive coupler providing a fixing of the coupler relative to the bulb which, when the conductor is connected to a source of RF electrical potential, conducts a RF current producing a RF electrical potential on the electrically conductive coupler that produces the RF electrical field coupled to the light emissive fill.

Abstract: Induction lamp system comprising a power supply unit, which can supply a high-frequency altenating voltage, a power supply cable connected to the power supply unit and an induction lamp connected to the power supply cable. The lamp is provided with an induction coil, and at least one electronic component is arranged between the induction coil and the power supply cable. The electronic component together with the induction coil and the power supply cable have a combined impedance Z. According to the invention, and due to the properties of the electronic component, it holds that the absolute value of the imaginary component Im(Z) of the impedance Z is smaller than the real component Re(Z) for any arbitrary length of the power supply cable.

Abstract: The arc of an alternating current discharge lamp may be magnetically straightened by including a small direct current component to the lamp current. The lamp may then be operated substantially as an alternating current lamp, but with out the need to synchronize the magnetic field with the alternating lamp current. The minor inclusion of the direct current component enables the lamp to be magnetically deflected effectively for arc straightening, optical positioning of the arc, offset positioning from the envelope wall to preserve lamp life, and other useful functions.

Abstract: A system and method for operating a dual electrode flashlamp. The method employs steps of applying an electrical potential between a pair of electrodes of the dual electrode flashlamp; and irradiating a region behind one of said electrodes with microwave energy. The system has a flashlamp bulb; a first electrode positioned at one end of the flashlamp bulb; a second electrode positioned at another end of the flashlamp bulb; and a microwave energy source positioned to direct microwave energy at the flashlamp bulb.

Abstract: A starting system for an electrodeless metal halide discharge lamp includes a parallel tuned LC network including a fixed capacitor and a starting inductor, and also including a conductive plate for application to the starting inductor for detuning the network once the lamp has started. The detuned starting network produces insufficient voltage to maintain the starting plasma while the lamp is running. The conductive plate is removed from the starting inductor by a solenoid or other mechanical actuator during lamp starting.

Abstract: An RF source is periodically pulsed for exciting an electrodeless light bulb in an on-off mode so as to intermittently drive the bulb to a high peak power operating point where light generation efficiency is relatively high, while maintaining a relatively low average power input. Pulse rate and duration are optimized to minimize light flicker while maximizing light emission efficiency.

Abstract: Ignition of an electrodeless lamp, energized by microwave or radio frequency energy, is achieved by disposing a ferroelectric igniter in the lamp envelope along with the fill material. The igniter responds to switching of its spontaneous ferroelectric polarization by emitting electrons that collide with the atoms of the fill material to discharge further electrons and ultimately provide emission of light. In the preferred embodiment, the microwave or radio frequency energy used to excite the fill material is applied to the ferroelectric igniter to cause switching of its spontaneous ferroelectric polarization. Another preferred feature is the securing of the igniter, in the form of a thin patch or wafer, to the inside surface of the lamp envelope in a generally perpendicular orientation to the electric field in the microwave excitation energy.

Abstract: An excitation circuit for an electrodeless light bulb which includes an RF source, a driver amplifier, and a load matching network and where the frequency of the RF energy generated by the source is swept over a predetermined frequency range in a controlled manner by a programmable frequency controller to cover the entire range of possible load match tuning conditions so that the electrodeless bulb will be substantially matched at all times to the source at some frequency in the sweep range.

Abstract: An electric lamp assembly includes an electrodeless lamp having a closed-loop, tubular envelope enclosing mercury vapor and a buffer gas at a pressure less than about 0.5 torr, a transformer core disposed around the lamp envelope, an input winding disposed on the transformer core and a radio frequency power source coupled to the input winding. The radio frequency source supplies sufficient radio frequency energy to the mercury vapor and the buffer gas to produce in the lamp envelope a discharge having a discharge current equal to or greater than about 2 amperes. The electrodeless lamp preferably includes a phosphor on an inside surface of the lamp envelope for emitting radiation in a predetermined wavelength range in response to ultraviolet radiation emitted by the discharge.

Abstract: An illumination unit according to the invention comprises an electrodeless low-pressure discharge lamp 10. The illumination unit is provided with a lamp vessel 20 which encloses a discharge space 21 which contains an ionizable filling. The illumination unit is in addition provided with a holder 60 for the lamp vessel 20, with a coil 30 for generating a high-frequency magnetic field so as to maintain an electric discharge in the discharge space 21, and with a high-frequency supply 50 for the coil. The illumination unit is further provided with ignition aids 40 for promoting the initiation of the discharge.

Abstract: A lighting unit according to the invention comprises an electrodeless low-pressure discharge lamp 20 provided with a discharge vessel 20 enclosing a discharge space 20 with an ionizable filling in a gastight manner. The discharge vessel 20 has a recessed portion 23 and an enveloping portion 23 which transmits radiation generated in the discharge vessel. Means are present in the recessed portion for initiating and maintaining an electric discharge in the discharge space. The means comprise a member for generating an electric field in the discharge space. The recessed portion is provided with a luminescent layer, which is subdivided into mutually separated regions, at a surface facing the discharge space. The lighting unit further comprises a supply unit for supplying the means. The lamp of the lighting unit according to the invention has a comparatively low ignition voltage.

Abstract: A high intensity discharge light source that uses a pseudo-random sequence generator to modulate an RF drive signal, and reduce electromagnetic interference (EMI) produced by the light source. The light source includes a high intensity RF discharge lamp, control and RF drive electronics that are coupled between a power source and the lamp. The control and drive electronics include an electromagnetic interference filter, and a regulator that outputs a bias voltage. The drive electronics provide RF power to the lamp, and includes an oscillator, a mixer/modulator, an amplifier, and an impedance matching network. The control circuit includes a pseudo-random sequence generator that generates a pseudo-random sequence of pulses to modulate the mixer/modulator and thus the output of the oscillator to thereby reduce the EMI spectral density generated in driving the RF discharge lamp.

Abstract: A first portion of a spiral wire support for an amalgam is securely fitted into an exhaust tube formed in a re-entrant cavity of an electrodeless fluorescent lamp before attachment and sealing of the re-entrant cavity to the bulb of the lamp. A second portion of the spiral wire support extends into the bulb and holds an amalgam in thermal contact with the apex of the bulb. The second portion has a larger diameter than the first portion to ensure against movement of the spiral wire support into the exhaust tube. The end of the second portion of the spiral wire support is wetted with an alloy capable of forming an amalgam with mercury prior to insertion of the wire support into the exhaust tube. Mercury is added to the bulb after final evacuation of the bulb in preparation for dosing the lamp with its fill. As a result, an amalgam is formed and maintained in thermal contact with the apex of the bulb, regardless of lamp orientation.

Abstract: An impedance matching and filter network is disclosed. The network performs two preselected impedance transformations and provides a filtering function to attenuate harmonics of an electrical signal delivered at an input of the network. The network may advantageously be structured in the form of balanced dual filters which are referenced to a virtual ground between them, the virtual ground being connected to a shield which surrounds the electric components. The network is particularly suitable for use with electrodeless discharge lamps to provide an impedance matching function for the induction coil and to limit RFI.

Abstract: A glass rod extending through and sealed to the exhaust tube of an electrodeless SEF fluorescent discharge lamp has a metal support member at one end thereof for supporting an amalgam at or near the apex of the lamp envelope. The metal support member may comprise a spiral-shaped wire, a wire screen, or a wire basket. Preferably, the amalgam is maintained in contact with the apex of the lamp envelope. If desired, the metal support member may comprise a magnetic material to allow for magnetic transport of the amalgam assembly during lamp processing. The metal support member restricts spreading of the amalgam when in a liquid state; and the glass rod provides rigid support for the amalgam independent of lamp orientation.

Abstract: An electrodeless lamp which operates with a high efficiency and with a lower cooling requirement. The bulb is rotated at a high speed which results in a substantial increase in efficiency. Because more of the input energy is converted to light, and less to heat, the pressure of the cooling fluid source may be reduced, resulting in a less noisy system.

Abstract: An electrodeless lamp (e.g., an electrodeless fluorescent lamp) includes a dielectric housing shaped to conform to a portion of a lamp envelope, which housed portion is opposite to a portion through which light is emitted. The dielectric housing includes a continuous conductor, i.e., a shorted turn, situated between the dielectric housing and the lamp envelope which conforms to at least a portion of the dielectric housing. The configuration of the shorted turn, in terms of the location and amount of surface area occupied thereby, is optimized to minimize interaction between the excitation coil and any metallic fixture and to avoid interfering with lamp starting and light output.

Abstract: An impedance matching circuit for a self-oscillating electrodeless fluorescent lamp ballast of the type having an inductor connected in series with the parallel combination of a capacitor and the lamp's drive coil includes an additional capacitor connected in series with the drive coil. The capacitance value chosen for the additional capacitor is dependent on: stresses on the parallel capacitor; matching the impedance of the ballast; and the impact of the capacitor on the loaded coil phase angle. The additional capacitor reduces the phase angle presented to the ballast, thereby lowering the sensitivity of the ballast to component and lamp variations. In addition, the overall impedance of the network is reduced, such that the required inductance of the series inductor is reduced; hence, the inductor can have fewer turns and lower conduction losses.

Abstract: An amalgam is accurately placed and retained in an optimal location near the cold spot of an electrodeless SEF lamp for operation at a mercury vapor pressure in the optimum range from approximately four to seven millitorr. The amalgam is positioned at the tip of an extended exhaust tube near the apex of the lamp envelope by forming an indentation in the exhaust tube and, in some embodiments, a dose locating member in combination therewith. An evacuation hole is formed below the indentation for evacuation of the lamp envelope, or bulb, during lamp fabrication. In an alternative embodiment, the extension of the exhaust tube is situated perpendicular to the main portion of the tube to allow for lateral adjustment of the position of the amalgam, thereby allowing for even further control of the amalgam operating temperature.

Abstract: An electrodeless fluorescent lamp of the type having a solenoidal drive coil wound about a ferrite core includes an inner shield between the coil and the core and further includes an outer shield about the coil. The shields are preferably constructed of sheets of flexible polyimide material with vertical bands of metal etched thereon. The metal bands are connected to ground in order to shield the core and the plasma from the electric field generated about the drive coil. By thus shielding the core, the capacitance between the coil and the core is effectively short-circuited, substantially reducing or eliminating dielectric losses of the core. The outer shield substantially reduces the EMI generated by the drive coil.

Abstract: An ultraviolet starting aid is formed in a metal halide arc discharge lamp by forming a cavity in a press seal portion of an arc tube. An electrode is provided in the cavity which either extends external to the press seal, or the electrode may be a portion of molybdenum ribbon used in the press seal.

Abstract: The invention is directed to an induction coil which includes a flat spirally wound portion and a tubular spirally wound portion extending from the outer edge of the flat portion. The axis of the tubular portion is substantially perpendicular to the flat portion. The coil is useful in a plasma production apparatus which includes a chamber having walls and adapted to be evacuated. A window extends into the chamber from one of the walls. The coil is in the window with the flat portion being at the bottom of the window.

Abstract: A discharge tube arrangement comprises a launcher and a discharge tube positioned in part within the launcher. When the launcher is energized with radio frequency (r.f.) power, surface waves are excited in the discharge tube which contains a fill. An electrically conductive structure extends along the discharge tube and is connected to an earth when in use. The structure is separated from the discharge tube by a radial distance such that, in use, the discharge tube produces an increase in total light output over the total light output of a discharge tube not having this structure. The structure comprises an insufficient quantity of material to obscure this increase in total light output.

Abstract: A high intensity discharge electrodeless lamp having a segmented excitation coil and capacitor configuration offers minimum light obstruction and RF losses while providing maximum impedance matching and heat transfer from the coil to a heat sink. The excitation coil includes at least two pairs of interconnected windings, each pair disposed concentrically in its own plane. The windings are clustered in a toroidal shape, the center of which is positioned to surround the arc envelope of a high intensity discharge lamp containing an ionizable gas activatable by RF energy. The coil windings are of large cross-sectional area and the capacitors have short leads, so as to minimize EMI and power losses and facilitate heat condition to heat sink means. The windings are configured to follow the contours of the magnetic field lines created by current flow through the total coil.

Abstract: A pair of starting electrodes are provided for an electrodeless high-intensity-discharge lamp arc of the type having an envelope situated within the bore of an excitation coil and in the interior of which envelope is to be provided a plasma arc discharge driven by the excitation coil. Each of the starting electrodes is a conductive ring disposed adjacent to an associated one of an opposed pair of envelope surfaces, and connected to an opposite end of the excitation coil. A high-voltage signal coupled between the starting electrodes causes an electric field to be produced sufficient to create a glow discharge in the arc tube, and cause an almost instantaneous transition to a high-current solenoidal discharge to form the discharge plasma responsive to the normal field provided by the excitation coil.

Abstract: The invention concerns a method and apparatus to produce a noble-gas plasma for excitation in optical emission spectrometry. The apparatus includes an hf generator feeding an oscillation circuit consisting of at least one inductor and one capacitor. The capcitor includes at least two capacitor plates which are so shaped and mutually arranged that they enclose a cavity in which the plasma may form.

Abstract: An electrodeless lamp bulb comprises of a quartz envelope and a fill containing mercury in a ratio of from 0.5-0.9 microliters per milliliter of envelope volume at room temperature. A lamp including such bulb which is powered by microwaves.

Abstract: A metal halide arc discharge lamp comprises an arc tube containing a chemical fill including mercury and metal halides and having first and second electrodes respectively sealed at opposite ends thereof. An outer envelope surrounds the arc tube and has first and second terminals for electrical connection thereto. A source of ultraviolet radiation is provided within the outer envelope proximate the arc tube for producing radiation which illuminates the path between the electrodes of the arc tube to decrease the amount of time for generating a gaseous discharge therebetween. The ultraviolet light source includes an envelope of ultraviolet light transmitting material containing a fill material and having a single electrode sealed in one end thereof. The single electrode is electrically coupled to one electrode of the arc tube.

Abstract: A metal halide arc discharge lamp comprises an arc tube containing a chemical fill including mercury and metal halides and having first and second electrodes respectively sealed at opposite ends thereof. An outer envelope surrounds the arc tube and has first and second terminals for electrical connection thereto. An electrodeless source of ultraviolet radiation is provided within the outer envelope proximate the arc tube for producing radiation which illuminates the path between the electrodes of the arc tube to decrease the amount of time for generating a gaseous discharge therebetween. The ultraviolet light source includes an envelope of ultraviolet light transmitting material having opposing ends. Portions of the envelope of the ultraviolet light source are capacitively coupled across the electrodes of the arc tube such that the source produces ultraviolet radiation during lamp starting when the first and second terminals of the lamp are energized.

Abstract: An electronic light radiation tube wherein a cathode and an anode disposed as spaced from each other by a small spacing are housed in an envelope enclosing therein a luminous gas, and a magnetic field is applied to the envelope so as to cause magnetic lines of force of the magnetic field to pass through the envelope, while the magnetic lines of force which have passed through the cathode are prevented from passing through the anode, whereby electrons emitted from the cathode are caused to collide at a high efficiency with the luminous gas throughout the entire interior space of the envelope to excite the gas, and highly uniform light radiation can be realized over the entire envelope.

Abstract: An improved plasma arc reactor is provided with variably positionable electrodes, including a cylindrical anode electrode having an inner, frustoconical cavity providing a reaction chamber and a spherical cathode ball electrode mounted therein. Between these electrodes an arc discharge is induced and sustained to heat and ionize an inert gas to produce an arc plasma for refining raw material introduced into the reaction chamber. A magnetic induction coil is mounted around the outer diameter of the anode electrode to thereby establish a magnetic field to rotate the arc discharge and plasma within the reaction chamber.

Abstract: A microwave generated electrodeless lamp using a single magnetron, and an improved lamp envelope therefor. An elongated lamp envelope containing a plasma forming medium is disposed in a microwave chamber comprised of a reflector and mesh. The reflector includes a pair of coupling slots, each of which is disposed equidistant from the ends of the lamp envelope. A waveguide means is provided which has a wall which is comprised of a portion of the reflector which includes the slots, and has means for introducing microwave energy thereto at an area equidistant from the two slots so that the energy couples equally to the slots. When the frequency of the microwave energy and chamber dimensions are arranged so that a symmetrical standing wave exists in the chamber, a balanced system results wherein after a short start-up period, approximately equal light output is obtained from the respective ends of the lamp envelop.