Abstract: A magnetic thyratron interrupter is provided having between an anode and a cathode a structure having an aperture therein for a discharge presenting a succession of surfaces in the direction of discharge which are contacted when the discharge is moved by applying a magnetic field transversely to the discharge direction. Examples of structure are stacks of discs having concentric holes which are alternately of larger and smaller diameter and a strip of gauze wound into a spiral.

Abstract: A microwave powered electrodeless light source which is powered by two magnetrons which are excited successively.

Abstract: A high pressure sodium vapor lamp comprising an alumina arc tube within an outer glass envelope is provided with a capacitive starting aid in the interenvelope space. The aid comprises a stiff wire which is pressed lengthwise against the side of the arc tube by a bimetal arm swinging in a plane normal to the lamp axis. Preferably the wire has a camber concave towards the arc tube which is flattened out at room temperature. In the event of a reclosure, the camber shortens the hot restart time.

Abstract: A cold-cathode, plasma discharge modulator switch is disclosed. A crossed-field discharge plasma supplied charge carriers for the switch. A dc magnetic field is employed to provide a highly localized cusp magnetic field near the cathode, so that gas ionization occurs primarily in the cathode-source grid gap. The region between the cathode and anode is filled with a relatively low pressure gas. A highly transparent control grid with small apertures is closely spaced from the anode. The switch is closed through application of positive potential (relative to the plasma) to the control grid, and opened through application of negative potential relative to the plasma to the control grid. The application of negative potential to the control grid creates an ion sheath around the control grid which permits plasma cut-off to the anode region provided the sheath size is larger than the control grid aperture radius.

Abstract: A discharge lamp having a sealed glass vessel filled with gas and a metal vapor, operated with a supply at a frequency of at least 20 kHz. An interference-suppressing conductive layer is arranged on a wall surface surrounding the discharge, and connected to an electric supply lead-in wire. Preferably, a plurality of insulated metal rings, on the outside of the wall, also surround the discharge.

Abstract: Electrodeless gas discharge lamp having a lamp vessel which is closed in a vacuum-tight manner, the lamp comprising a rod-shaped core of a magnetic material, a member of a heat-conducting material (for example copper) extending at or near the axis of the core, heat generated in the core during operation of the lamp being discharged to the environment of the lamp by the member.

Abstract: Vapor deposition coating can be performed in apparatus in which a plasma of the coating material is generated from the surface of an electrode. The surface area of the electrode from which the plasma is generated can be selectively adjusted by exposing the plasma generating surface of the electrode to the influence of a magnetic field and adjusting the strength of the magnetic field to spread plasma over the evaporative surface of the electrode to permit more efficient utilization of the electrode. Preferably, the electrode is in the form of a flat metal disc (e.g. titanium) and the magnetic field is generated by a wire coil that substantially encircles or is coaxial to the electrode, with the electrode or an associated element functioning as a core for the coil.

Abstract: A microwave generated electrodeless light source for producing a bright output comprising a lamp structure including a microwave chamber and a plasma medium-containing lamp envelope having a maximum dimension which is substantially less than a wavelength disposed therein. To provide the desired radiation output the interior of the chamber is coated with a UV-reflective material and the chamber has an opening for allowing UV radiation to exit, which is covered with a metallic mesh. The chamber is arranged to be near-resonant at a single wavelength, and the lamp envelope has a fill including mercury at an operating pressure of 1-2 atmospheres, while a power density of at least 250-300 (watts/cm.sup.3) is coupled to the envelope to result in a relatively high deep UV output at a relatively high brightness.

Abstract: A miniaturized vapor discharge lamp assembly that includes a light transmissive bulb containing a buffer gas and a vaporizable light radiating substance such as rubidium. Lamp excitation is provided by the use of a capacitor in the lamp assembly in conjunction with an RF oscillator. The capacitor establishes a substantially longitudinal electric field which ionizes the rubidium vapor to cause emission of light. The need for an RF excitation coil is eliminated.

Abstract: A high-coulomb transfer switch useful for high current pulse power supplies employs an inverse-pinch mechanism to sweep the arc current sheet over the electrodes. The inverse pinch currents are formed by a special electrode configuration wherein the inner electrode has the shape of a mushroom with the "cap" surrounding the "stem" so that the currents flowing in the electrode enclose the magnetic induction around the "stem". This results in repulsive forces on the outer currents in the "cap" causing the arc current sheet to rapidly move from the lip at the "cap" where the arc is initiated upward to the crown of the "cap" where occurs the final decay of the current. In the disclosed preferred embodiment, the inner, outer and return electrodes are generally cylindrical and placed coaxially. The switch can be operated under a vacuum or under a high pressure gas.

Abstract: An improved oscillator circuit primarily for use as an RF source circuit for igniting a light discharge in a rubidium lamp used in a rubidium vapor cell frequency standard. A number of novel features are disclosed including an adjustable power capability dependent on current sensed feedback providing power adjustment over at least a 5-to-1 ratio; lamp heater monitoring for high oscillator power operation during warm-up; and light intensity monitoring for feedback bypass and high oscillator power operation whenever inadequate light discharge is detected.

Abstract: An electrodeless gas discharge lamp having a closed loop core of a magnetic material the part of which core extends through the lamp vessel, a high frequency field being induceable in this core by means of an h.f. generator in the lamp base, said core is assembled of at least two operable core portions at least a major part of one portion lying within the lamp vessel, and the other of the two portions being located in the lamp base, the lamp base being detachably secured to the lamp vessel.

Abstract: An operating circuit and method for efficiently operating and starting an electrodeless lamp having a magnetic core operated at radio frequencies. The circuit generates a current which flows through the winding of an electric field inducing means in the lamp in a reverse-bias direction, with respect to a drive current, to operate the core of the inducing means in all quadrants of the B-H curve, with the time average of all current through the lamp winding equaling approximately zero in order to avoid or minimize heat energy losses and sharp current peaks caused by saturation. This also allows use of lower current-capacity less-expensive components. The circuit repetitively applies constant-current DC drive pulses to the lamp winding for a small percentage of an interval during which energy is stored, which is used to generate the reverse-bias current.

Abstract: It is desirable not only to switch between circuits or circuit elements carrying relatively large currents but also to effect the switch-over operation extremely rapidly. Conventional thyratrons can be used to switch on the current, but they cannot easily be switched off so quickly.The invention seeks to solve this "switch-off" difficulty by using the principle of plasma particle diversion together with a new thyratron design which can be used as a "switch-over" device. As can be seen from FIG.

Abstract: Gas density variations between two electrodes are controlled by directing a gas stream into the region between the electrodes. Inside a vacuum chamber there are suitably arranged electrodes in the form of a cathode and an anode, and also a pulse gas source, as well as, preferably, a suitable winding.

Abstract: A method and apparatus for igniting a microwave generated discharge lamp. An ultraviolet-producing means is positioned so as to irradiate the fill-containing envelope of the discharge lamp. The ultraviolet-producing means is excited by microwave energy which is extracted from means which couples microwave energy from the microwave source to the fill-containing envelope of the discharge lamp.

Abstract: Crossed-field plasma mode electric conduction control device 10 has an interelectrode space 16 between anode 12 and cathode 14 in which is produced a magnetic field 38 by coil 28. Electrons produced at region 46 travel through the crossed-fields to region 48, with cascading ionization to produce an electrically conductive plasma. The electrons are lost at region 48 and plasma density is controlled by magnetic field strength to control magnitude of interelectrode current.

Abstract: High frequency electrodeless (HFE) lamp has high-permeability core such as ferrite positioned in energy transferring relationship with respect to the phosphor-coated lamp envelope. The core forms a part of a tuned circuit output for a radio-frequency energizing source and during lamp operation, the resulting electromagnetic fields generated within the lamp envelope create a discharge which in turn generates radiations to excite the phosphor to produce visible light. The core is specially designed to include narrow gap means of low-permeability substance and this gap improves lamp performance by providing the dual function of stabilizing the output frequency of the tuned circuit to compensate for variations in permeability of the core and, in addition, the resulting increased Q of the tuned circuit substantially suppresses harmonics of the resonant frequency which are undesirable in such a lamp.

Abstract: A system based on the magnetic compression of ion rings, for generating intense (high-current), high-energy ion pulses that are guided to a target without a metallic wall or an applied external magnetic field includes a vacuum chamber; an inverse reflex tetrode for producing a hollow ion beam within the chamber; magnetic coils for producing a magnetic field, B.sub.

Abstract: A plasma switch comprising a substantially evacuated chamber, a generally tubular cathode disposed within the chamber, an elongated anode disposed concentrically within and projecting from the opposite ends of the cathode, the opposite ends of the cathode being substantially closed by an electrically conductive end plates, at least one of such end plates being electrically insulated from the cathode and from the anode, and circuit means for selectively connecting such end plate to the anode or to the cathode.

Abstract: A cross-field discharge plasma is used to supply charge carriers for a grid controlled cold cathode discharge device. A dc magnetic field is employed to sustain the crossed-field discharge when the source grid is active. The device comprises an anode, a cathode, a source grid, and in alternate embodiments, additional control grids. Preferably the magnetic field exists only in the source grid-cathode space and penetrates only weakly, or not at all, into other electrode gaps or spaces. The source grid-cathode plasma is effectively a source of charge carriers, electrons or ions, controlled by the source grid current, the anode current being an approximate linear function of source grid current within limits, and/or controllable by adjustment of control grid potentials.

Abstract: High-frequency electrodeless discharge device is operated by radio-frequency energy generated by an oscillator operating in Class E mode. By proper selection of the oscillator circuit components, a load-network capacitor can be eliminated along with an inductor which is normally required to pass direct current to the transistor switch portion of the oscillator. The elimination of these elements permits the oscillator to be packaged in compact fashion. The discharge device incorporates a looped core of high permeability material which forms a part of the tuned circuit output portion of the oscillator and the radio frequency energy electromagnetic fields passed through and about the core and within the envelope of the device excite a discharge-sustaining medium to generate plasma which is converted to visible radiations.

Abstract: A metallic coating is disposed on the inner surface of a lamp having an envelope made of a light transmitting substance enclosing a fill material which emits light upon breakdown and excitation by a high frequency power source. The metallic coating protects the lamp envelope from degradation caused by the lamp fill material or by products of the discharge and acts as a catalyst for the recombination reaction of molecular lamp fill material. A nickel coating is used in a deuterium discharge lamp. Another suitable metal is gold. The metallic coating is sufficiently thin to permit high frequency power to pass through the coating.

Abstract: An electrodeless lamp apparatus includes an electrodeless, light-transmitting, envelope for housing a rare-earth compound fill, and a termination fixture, electrodelessly coupled to the envelope, adapted to create an electrical condition for exciting the fill.The fill can include mercury and a noble gas, such as argon.The rare-earth compound is preferably a rare-earth halide, such as dysprosium iodide and holmium iodide.The fill can include a halide of mercury, such as HgBr.sub.2.One example of a fill is Hg/DyI.sub.3 /HoI.sub.3 /CsI/HgBr.sub.2 /Ar.A second example of a fill is Hg/NdI.sub.3 /DyI.sub.3 /CsI/Ar.A third example of a fill is Hg/Pr/DyI.sub.3 /HgI.sub.2 /CsI/HgBr.sub.2 /Ar.A fourth example of a fill is Hg/Yb/CsCl/HgCl.sub.2 /Ar.

Abstract: A spectral source comprises a lamp containing an anode and a cathode in an inert gas. The anode and cathode are different in shape and connected to a high-frequency power source to produce a high-frequency discharge between the anode and cathode to cause both sputtering of the cathode and excitation of a radiation having the spectrum according to the material sputtered from the cathode. The application of solely high-frequency power prevents adherence of the sputtered material to the interior walls of the lamp bulb thereby allowing a reduction of the dimensions of the lamp bulb, prolongating the life time of the lamp and increasing the stability and intensity of the radiation. A magnetic field may be applied to the radiation for Zeeman modulation. Due to the relatively small dimensions of the lamp bulb, relatively small and inexpensive magnets may be used.

Abstract: Novel geometries for high intensity discharge solenoidal electric field lamps are disclosed providing good coupling between the magnetic fields within the ferrite and the plasma discharge. In addition, the geometries provide for good heat sinking and cooling capabilities as well as escape of most of the generated light. In accordance with one embodiment of the present invention, a plurality of toroidal shaped ferrite cores are arranged about the high intensity discharge tube, the tube being threaded through the holes in the toroidal ferrite cores. In accordance with another embodiment of the present invention, a bundle of ferrite rods is disposed through the hole of a toroidal shaped discharge tube, the packing density of the ferrite rods in the bundle being less than one hundred percent efficient whereby channels for cooling air are formed.

Abstract: An electrodeless fluorescent light source that includes a non-conducting light transmissive hermetically sealed envelope containing an ionizable gas which is electromagnetically coupled to an ionizing radio frequency (r.f.) energy source is described. The r.f. energy source is an induction coil wound in the form of a toroidal helix to minimize microwave radiation leakage, and is placed within the envelope and in direct contact with the gas in order to maximize energy coupling to the gas.

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 interrupter which can be used as a high voltage d-c breaker or fault current limiter transfer switch or the like contains a pair of cooperable contacts disposed in an evacuated container. One of the contacts also serves as the cathode of a magnetically modulated vacuum arc discharge device. This cathode is spaced from an anode disposed in the wall of the evacuated housing. The anode is surrounded by a winding which is capable of producing a magnetic field which can increase the impedance of the arc plasma between the cathode and anode in order to decrease the arc current and extinguish the arc. The cooperable contacts within the interrupter serve to carry load current and also serve to create the inital arc which is transferred between the anode and cathode structures.

Abstract: In an electrodeless fluorescent lamp of the type including a sealed, light transmissive, envelope including an elongate inner wall defining an open-ended cavity and an outer wall surrounding the inner wall to form a generally annular, hollow cavity therebetween, the annular cavity being charged with an ionizable gaseous medium, an induction coil positioned within the open-ended cavity, and a radio frequency oscillator connected to the coil, the coil and the oscillator initiating and maintaining ionization of the medium to form an ultraviolet light emitting discharge, the inner surface of the outer wall of the envelope being coated with a phosphor which emits visible light when excited by ultraviolet light, the improvement wherein the outer surface of the inner wall is coated with a layer of an electrically insulative ultraviolet light reflective material which is overcoated with a phosphor layer. Such improvement yields an increase in visible light production of the order of 50% to 100%.

Abstract: The header and tunnel of an external core, solenoidal electric field, fluorescent lamp are coated with a thin ultraviolet light-reflective layer; for example, aluminum or magnesium oxide. Radiative heat transfer from the lamp plasma to the magnetic core is thus reduced to permit high operating power levels and good lumen maintenance.

Abstract: An anode and a cathode are disposed in an opposing relation in a tubing in which an inactive gas is enclosed to form a discharge lamp by which an atomic spectrum is emitted. The cathode contains atomic spectrum emitting elements also serving to form the material of cathode. The discharge lamp is supplied with a high frequency power from a high frequency source and simultaneously with a direct current power from a direct current source. This causes the direct current discharge and high frequency discharge to be effected between a pair of electrodes in a superimposed manner. The atoms sputtered by the direct current are efficiently excited by the application of the high frequency with the result that atomic spectra with high brightness are obtained.

Abstract: An auxiliary magnetic field coil is associated with the interelectrode space of a crossed-field switch device for ignition of the crossed-field switch device when high voltage is applied across the interelectrode space. The auxiliary magnetic field coil produces a localized field in which physical conditions cause conduction in the glow mode. Once conduction is started, the interelectrode voltage falls and with the main magnetic field applied to the entire effective interelectrode space, normal glow mode conduction takes place.

Abstract: A circuit interrupting device for providing protection against surge currents is constructed to operate very rapidly. A surge current generates a magnetic field in coils which deflects an electron beam which normally travels from a cathode to an anode to complete an electric circuit.

Abstract: A solid state microwave power source for providing microwave power to excite an electrodeless lamp is designed so as to provide an acceptable impedance matching characteristic during lamp warm-up when the lamp impedance is high and changing with temperature to provide sufficient power to the lamp during the running state when the lamp impedance is matched to the source. The microwave power source includes a dc power source providing power at variable levels, a microwave oscillator receiving the dc power to produce a microwave signal, and a microwave power amplifier. The oscillator has a transistor in a common base configuration, a microstrip capacitive feedback element to sustain oscillations, and an output impedance matching arrangement formed from microstrip. The microwave signal is amplified in the solid state power amplifier having a power transistor in a common base configuration.

Abstract: Improved efficacy is obtained in an electrodeless light source of the type having a high frequency electrodeless lamp disposed at the ends of inner and outer conductors of a termination fixture by evacuating the region between the lamp envelope and the outer conductor to reduce conductive and convective heat losses.

Abstract: A starting assist control circuit for an electrodeless light source in which a UV source for assisting in starting an electrodeless lamp is coupled in series with the DC supply for a microwave power source for the lamp so that a reduced DC voltage is supplied to the microwave power source at lamp starting. An electronic circuit is provided which continuously decreases the DC current through the UV source and increases the DC voltage for the microwave power source in relation to the amount of light generated by the electrodeless lamp. More specifically, the emitter and collector of a transistor are coupled across the UV source to provide a shunt path and the potential of the base of the transistor is controlled by a photosensitive resistor which senses the amount of light from the lamp. As the lamp generates increased light, the transistor becomes more conductive, thereby continuously decreasing current to the UV source and increasing voltage to the microwave power source.

Abstract: A power supply circuit having a crystal controlled solid state oscillator induction coupled to a dual transistor circuit so as to eliminate second harmonics in a coil connected thereto and to a power supply in completing the circuit, and coil further having a resonance circuit therearound. Such power supply being suitable for driving a plasma gas envelope.

Abstract: A starting assist control circuit for an electrodeless light source in which a UV source for assisting in starting an electrodeless lamp is coupled in series with the dc supply for a microwave power source for the lamp so that a reduced dc voltage is supplied to the microwave power source at lamp starting. At staring, a capacitive impedance element is coupled across the inner and outer conductors of the fixture to provide an additional starting assist by creating a condition of resonance in the fixture. A heat responsive bimetallic switch element associated with both the capacitor and the UV source automatically shorts out the UV source and decouples the capacitor after the lamp has started thereby permitting full dc power to the microwave power source during the operating condition of the lamp.

Abstract: A lamp for use on a radio antenna is disclosed. The lamp consists of a neon bulb encapsulated in a transparent or translucent covering, with the bulb leads secured in an electrically conductive tube. The tube is adapted for connection to and support by an antenna, whereby the bulb is responsive to RF energy radiated by the antenna to illuminate the lamp.

Abstract: In addition to the anode and cathode electrodes which define a low pressure gas filled main gap therebetween and a magnetic field to lengthen the electron path, the crossed-field switch device has a control electrode defining a second gas filled control gap in communication with the first, main conducting gap. An auxiliary voltage supply can be connected to the control gap to ignite a low pressure discharge, and the ionized plasma of this discharge leaks into the first gap to start a discharge in the glow mode.

Abstract: Three electrodes define two gaps in the crossed-field tube so that while one gap is holding off high voltage the other can be ignited to turn the tube on with high voltage applied. The three electrodes act as anode, cathode and control electrodes and define the main and ignition gaps. The intermediate electrode is gridded and the control electrode is connected to one of the other electrodes through an impedance to prevent hollow cathode discharge.

Abstract: An electrodeless discharge lamp has an ionizable medium comprising a particular gas composition at a particular pressure within a sealed envelope. Radio frequency electrical power is applied to an induction coil, the magnetic induction field of which is coupled to the medium. For a particular radio frequency, the magnitude of the induction field is selected to maximize the light emitted by the discharge per watt of radio frequency power coupled thereto. The radio frequency is preferably between 3 megahertz and 300 megahertz.

Abstract: A light source includes a source of high frequency power, an electrodelsss lamp and a termination fixture for coupling power to the lamp, the fixture having an outer conductor and an inner conductor whose length is adjustable for providing dynamic matching of the impedance of the lamp during the operating mode to the output impedance of the source. Variations in the power level from the source, such as is desirable in providing lamp brightness selectivity, vary both the real and imaginary components of the lamp impedance, and corresponding adjustments of the inner conductor length provide a tuning technique to compensate for these variations.

Abstract: A betatron is disclosed comprising an electromagnet having the gap thereof defined by the shaped tips of its pair of pole cores contains therewithin a vacuum accelerating chamber. The gap contains therewithin at least one bias winding connected in series with the magnetizing winding of the electromagnet. Both windings are excited by one and the same current pulse generator and are coupled to its energy accumulator via the switching elements of the generator. The switching elements of the generator, which return the energy stored by the electromagnet to the accumulator, are coupled to the magnetizing winding.

Abstract: An electrodeless discharge lamp system which is adaptable to an atomic absorption spectroscopy unit which is designed for hollow cathode discharge device operation.

Abstract: A resonance lamp having a controllable chemical decomposition source of a parent species and a chemical getter sink in a sealed RF excited discharge. The discharge occurs in a second, extremely pure gas which is present in great excess over the gas produced by chemical decomposition. Excitation of species whose emission is desired occurs by electron impact or energy transfer from the major species which are, in turn, excited by the electron impact.