Abstract: A microwave-excited discharge lamp (2) is constructed with a double-case structure consisting of an outer case (3) disposed in a microwave electromagnetic field, and an inner case (4) disposed inside the outer case.

Abstract: The present invention relates to a device for attenuating unwanted waves appearing in an electron tube which includes at least two coaxial cylindrical electrodes (2, 3). The electrodes (2, 3) contribute to forming the walls of a coaxial resonator. The unwanted waves to be attentuated generate surface currents in the walls of the coaxial resonator. The attenuation device includes several electrically conducting resistive elements (10) inserted into at least one wall of the resonator and arranged so as to cut the surface currents.

Abstract: A method and apparatus for exciting an electrodeless light bulb containing material including an inert gas and one or more chemical elements which generate a light emitting torus of plasma when excited by an RF signal and which includes two separate excitation coils oriented about the bulb so that the planes of each of the coils are mutually oriented 90.degree. with respect to each other, and wherein each of the coils are driven by respective RF excitation voltages having mutually different frequencies, for example, a difference of 4%, so as to excite the material enclosed within the bulb and cause a stirring action of the fill and effect a pulsating emission of light and rotation of the torus similar to that produced by physical rotation of the bulb itself.

Abstract: A power supply for an electrodeless lamp having an exterior starting electrode and first and second magnetrons coupled to the lamp comprises first and second power sources for being connected to the respective first and second magnetrons; a switch having first and second positions, the first position for disconnecting the second power source from the second magnetron and connecting the output of the second power source to the output of the first power source such that they are added together for being connected to the first magnetron during starting of the lamp, the second position for disconnecting the second power source from the first magnetron and connecting the second power source to the second magnetron after the lamp has started; and a controller adapted to synchronize the starting of the first and second power sources and the starting electrode such that they are turned on at the same time during starting of the lamp.

Abstract: The spectral energy characteristic of a discharge lamp is controlled by changing the density of the fill substance. The spectral characteristic can be shifted while substantially maintaining its shape by changing the density of the fill. A sulfur or selenium containing discharge lamp which is operated at a pressure of at least about 1 atmosphere contains a low ionization potential substance in the fill. Characteristics which are improved are one or more of spatial color uniformity, extinguishing characteristics, and bulb starting reliability. Particular substances which are added to the fill are alkali metal containing substances, III B metal containing substances, and alkaline earth metal containing substances. When light is reflected back into the bulb, the light which is re-emitted is stronger in the higher wavelengths.

Abstract: A microwave powered electrodeless lamp includes an improved screen unit having mesh and solid sections with an internal reflector secured at the juncture of the two sections to reflect light into a light-transmitting chamber defined in the lamp microwave cavity by the reflector and the mesh section. A discharge envelope of a bulb is disposed in the light-transmitting chamber. Light emitted from the envelope is prevented by the reflector from entering the cavity portion bounded by the solid section of the screen. The reflector is mounted in the cavity by tabs formed in the screen unit and bendable into the cavity to define support planes abutting respective surfaces of the reflector. The mesh section and tabs are preferably formed by etching a thin metal sheet.

Abstract: An electrodeless lamp arrangement powered by RF energy. The lamp arrangement having an envelope that is rotated and most importantly the envelope forms the center of a coaxial arrangment used to transfer the RF energy into the envelope.

Abstract: An electrodeless lamp comprises an envelope containing a fill; a starting electrode in proximity to a given region of the envelope when lamp is started; a field emission source disposed inside the envelope at the given region; starting power source coupled to the electrode for applying an electric field to the field emission source to cause a discharge; and excitation power source coupled to the fill to sustain the discharge. A method for starting an electrodeless lamp is also disclosed, comprising the steps of providing bulb comprised of an envelope and a discharge forming fill in the envelope; providing a field emission source on an interior surface of the envelope at a given region; applying an electric field at the given region to cause field emission from the field emission source to cause a discharge; and coupling a power source to the fill to sustain the discharge.

Abstract: A high intensity discharge lamp without mercury is disclosed radiating a selected spectrum of which can be almost entirely in the visible range from an envelope that contains a sulfur containing substance. The lamp utilizes a signal source that generates an excitation signal that is externally coupled to the exterior surface of the envelope to excite the enclosed sulfur containing substance. Various embodiments of the lamp use electrodes adjacent the envelope to couple the excitation signal thereto with the face of the electrodes shaped to complement the shape of the exterior surface of the envelope. Two shapes discussed are spherical and cylindrical. To minimize filamentary discharges each envelope may include an elongated stem affixed to the exterior thereof whereby a rotational subsystem spins the envelope.

Abstract: An electrodeless lamp assembly includes an electrodeless lamp capsule, a substrate having top and bottom surfaces and an edge, an applicator for coupling electrical energy to the lamp capsule and a refractory support block. The support block includes a top wall having a recess and a side wall having a groove. The lamp capsule is affixed in the recess, and the edge of the substrate is secured in the groove. The lamp capsule is supported above the substrate by the support block. During assembly, the support block may be moved along the edge of the substrate, and the lamp capsule may be moved with respect to the support block to adjust the position of the lamp capsule.

Abstract: A microwave powered electrodeless lamp includes an improved screen unit having mesh and solid sections with an internal reflector to reflect light into a light-transmitting chamber defined in the lamp microwave cavity by the reflector and the mesh section. A discharge envelope of a bulb is disposed in the light-transmitting chamber. Light emitted from the envelope is prevented by the reflector from entering the cavity portion bounded by the solid section of the screen. Replacing mesh material by solid metal material as part of the screen unit significantly reduces leakage of microwave energy from the lamp. The solid section has multiple compliant fingers defined therein for engaging the periphery of a flange on the waveguide unit so that a hose clamp can easily secure the screen to the assembly. Screen units of this type having different mesh section configurations can be interchanged in the lamp assembly to produce different respective illumination patterns.

Abstract: An apparatus which couples microwave energy to an electrodeless lamp. A source of microwave energy is connected to a wave guide having a slot along one wall thereof. A nominally cylindrical cavity enclosing an electrodeless lamp is closed at one end and coupled at a second end to the slot. The nominally cylindrical cavity has a non cylindrical surface portion which increases coupling from said slot to a second resonant mode which is orthogonal to a first primary resonant mode, creating a high amplitude standing wave in the region of the electrodeless lamp. Once ignition of the lamp occurs, the impedance of the lamp decreases significantly, and most of the microwave power for sustaining illumination is coupled to the electrodeless lamp in the first resonant mode producing a substantially matched load to said microwave source.

Abstract: Method and apparatus for generating radiation of high power, variable duration and broad tunability over several orders of magnitude from a laser-ionized gas-filled capacitor array. The method and apparatus convert a DC electric field pattern into a coherent electromagnetic wave train when a relativistic ionization front passes between the capacitor plates. The frequency and duration of the radiation is controlled by the gas pressure and capacitor spacing.

Abstract: An electrodeless lamp is started by coupling microwave power of a first frequency to a lamp cavity, while the discharge is maintained by coupling microwave power of a second frequency, wherein the first frequency is lower than the second frequency. A cooling fluid is impinged on the lamp bulb immediately before the application of the microwave power of the first frequency.

Abstract: A device for generating an ion beam, particularly for the continuous processing of large surfaces, includes an ionising chamber with a gas being fed thereinto to be acted upon by a high frequency alternating electrical field, extraction optics capable of extracting ions from the ionising chamber and generating an ion beam from the device, and excitation means capable of creating the high frequency alternating electrical field within the ionising chamber through a connection, by a waveguide, to a microwave generator. The excitation means include a conductive enclosure engaging one wall of the ionising chamber, wherein the inner space of the conductive enclosure is divided into a first portion, opposite the ionising chamber, to which the waveguide is connected, and a second portion, adjacent the ionising chamber, in which cylindrical conductive cavities are uniformly distributed, with each cavity comprising an adjusting means for adjusting the amount of microwave energy passing through that cavity.

Abstract: An electrodeless discharge lamp includes a single type auxiliary electrode for preliminary discharging, disposed on or adjacent to outer peripheral wall of lamp tube at a position for being electrostatically coupled to interior space of the tube, and supplied with a power from a second high frequency power source other than a first high frequency power source supplying a high frequency power to a main induction coil on the tube, whereby the lamp is made to attain an excellent startability without requiring any large size high frequency power source.

Abstract: The invention is directed to the reduction of an electron beam transport problem during microwave generation in plasma-assisted microwave sources. A small, e.g., <200 gauss, secondary magnetic field is positioned in association with a slow-wave structure (SWS) of the sources to reduce the radial divergence of electron bunches in the sources' electron beams. The secondary magnetic field exerts radial forces on diverging electrons to supplement radial forces of a primary magnetic field and radial forces of an electrostatic field. The primary magnetic field is generated by electron movement in the electron beam and the electrostatic field is generated by ions which are created as the electron beam transits an ionizable gas in the plasma-assisted source. The addition of the secondary magnetic field can be implemented with a coil that is positioned to direct at least a portion of its magnetic field through a passage of the SWS.

Abstract: Improved material and method for reflecting light in a photoinduction chamber is provided. The material comprises one or more layers of expanded polytetrafluoroethylene (ePTFE) membrane. Employing an ePTFE membrane as a reflective surfaces is demonstrated as providing excellent diffuse reflective properties, especially in the ultraviolet and visible ranges of light. Additionally, the material of the present invention has many other properties that make it particularly desirable for use in various photoinduction chamber applications, including inertness, flexibility, ease in shaping and installation, etc.

Abstract: An excimer lamp utilizing a high pressure fill. The fill includes a halogen at an operating pressure of greater than about 350 torr or the combination of a halogen and a rare gas at a total operating pressure of greater than about 2.5 atmospheres.

Abstract: Microwave amplifiers are disclosed having a hollow helix slow-wave structure coupled directly to input and output waveguides. This helix-waveguide coupling structure couples the TEM mode of the helix to the TE10 mode of the rectangular waveguides and also defines ports communicating with the helix interior. Heating of the helix during high-power operation can be removed by cooling liquid pumped through the helix via these ports. The helix is surrounded by a cylindrical housing containing a low-pressure ionizable gas which forms a plasma channel that focuses the electron beam without the need for surrounding magnetic structures. A plasma cathode electron gun is arranged to inject an electron beam through the helix. Backflowing ions from the housing are harmlessly absorbed into the face of the plasma cathode. The microwave amplifier is converted to a backward wave oscillator by coupling a load to one of the waveguides.

Abstract: A system for extracting a high power beam from a vacuum in which a beam is generated into atmosphere, which system is formed of: (a) a thin foil window of a material having good heat dissipation properties positioned adjacent the vacuum to permit the beam to pass therethrough; and (b) an air dynamic window between the foil window and the atmosphere. The foil window and air dynamic window are designed such that most of the pressure ratio drop from vacuum to atmosphere is across the foil window and most of the pressure drop in psi is across the air dynamic window.

Abstract: A device for charging PFLs (Pulse Forming Lines) on a time scale of a few nanoseconds. The device includes a source transmission line (STL) connected through a switch to a pulse forming transmission line. The source line is initially charged while the PFL is uncharged, and the switch is open. The impedance of the STL is larger than the impedance of the PFL. The impedance of the STL is also tapered in order to effect an energy transfer efficiency approaching 100% from the STL to the PFL. In operation when the switch is closed, energy flows from the source line to the PFL. As the energy and voltage build on the PFL, an output switch closes and delivers the energy of the PFL to the output transmission line section. The impedance of the output transmission line section is matched to the PFL impedance so that all of the energy in the PFL flows into the output section in the form of a pulse.

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: The Atmospheric Energy Projection System (AEPS) is a means to project electrical/thermal energy using microwave radiation at the resonant frequency of oxygen. The radiation excites a column through the ambient atmosphere to a temperature such that air within the column is converted from an insulator to a conducting channel or focused medium. An electrical current is subsequently applied to the channel to transmit an electric charge a predetermined distance. Rapid release of pulses of 60 GHz microwave radiation at a field strength below that for breakdown for the waveguide feeding the antenna or at the antenna aperture creates a channel without premature plasma generation. Once the channel is energized sufficiently, an electric charge is released into the channel and flows down it from the source to whatever solid the channel intersects. If no solid intrudes the charge diffuses harmlessly at the end of the heated channel as the channel cools back to the ambient temperature.

Abstract: A fluorescent lamp for use in special applications includes an electrodeless envelope of glass or other light transmissive material carrying fluorescent material within the envelope. An RF energy source and coupler are embedded in epoxy as an integral power unit, thereby isolating the power unit from the hazardous environment. The power unit and the envelope are shaped in complementary form such that the coupler and envelope are in energy-transfer relation to excite the lamp, but the envelope may be removed from the power unit to re-lamp the fixture.

Abstract: Apparatus for efficiently exciting an electrodeless lamp to produce visible light. A source of microwave energy is coupled to a cylindrical cavity which encloses an electrodeless lamp. The cylindrical cavity includes a sidewall and end wall which is made from a metallic mesh which passes light produced from the electrodeless lamp. The electric field intensity within the cylindrical cavity is increased in the region above the lamp center. The increased electric field intensity produces a more uniform temperature across the bulb service, increasing the rate of plasma heating of gas molecules in the lamp.

Abstract: A fluid-cooled dielectric window for a microwave plasma system which uses microwave absorbing fluids is described. The window includes a dielectric window and a cooling member in contact with an outer surface of the window which defines a channel and a medium adjacent to the channel. The channel transports a microwave absorbing cooling fluid over the outer surface of the window. The medium allows an electric field to enter through the window and sustain a plasma in a chamber while the fluid is flowing through the channel.

Abstract: An electrodeless high intensity discharge lamp includes an electrodeless lamp capsule, first and second electric field applicators positioned so that the lamp capsule is between the electric field applicators, and a planar transmission line. The planar transmission line couples high frequency power from an input to the first and second electric field applicators and has a gap with in which the lamp capsule is positioned. A field symmetrizing conductor, preferably a thin wire, is located in an open side of the gap and is electrically connected to the ground plane of the planar transmission line. The field symmetrizing conductor is positioned such that the electric field in the lamp capsule is substantially symmetrical with respect to the lamp axis and is substantially colinear with the lamp axis.

Abstract: An input transformer for a coaxial transmission line is provided which allows continuously variable amplitude and phase of an RF signal conducted on the transmission line. The transformer comprises a housing having a longitudinal axis. A center conductor of the coaxial line extends along the axis through the housing. A first sleeve is axially movable within the housing, and has contact points on an outer surface thereof to provide electrical conductivity between the first sleeve and the housing. The ability of the first sleeve to move axially enables variability in the location of the transformer along the transmission line. The first sleeve has an inner wall that is eccentric relative to the longitudinal axis of the center conductor. A second sleeve having a cylindrical outer wall is disposed within the first sleeve. The second sleeve is rotationally movable within the first sleeve, and has contact points on the outer wall to provide electrical conductivity between the first sleeve and second sleeve.

Abstract: A microwave oven has a cooking chamber and a microwave generator for supplying microwaves to the cooking chamber. The microwave generator is in the form of a klystron which produces a plurality of electron beams for amplifying microwaves.

Abstract: A simple and effective technique for reducing an external magnet flux emitted from a driven inductor surrounded by an ionizable gaseous medium. This technique includes surrounding the inductor with at least one shielding conductive loop, terminating the shielding loop in a capacitive termination to resonate, and maintaining a resonant frequency of the capacitive termination in series with an inductance of the shielding loop below the predetermined driving frequency of the inductor.

Abstract: Multiple radio frequency (RF) outlet ports are provided along the side of a slow wave tube to establish a distributed RF output in response to the transmission of an e.sup.- beam through the tube. The tube has a periodically rippled inner surface, and the outlet ports are spaced along the tube by substantially integral numbers of ripple periods. When implemented as a backward wave oscillator, RF power is extracted during a single pass through the tube; a travelling wave tube amplifier implementation is also possible. The separation of the RF extraction from the absorption of the e.sup.- beam at the end of the tube eliminates RF reflections and permits water cooling of the e.sup.- beam absorber. The RF extraction ports are also preferably configured as built-in mode converters from a TM.sub.01 cylindrical tube mode to a TE.sub.10 rectangular extraction mode, with four symmetrically arranged rectangular extraction waveguides at each extraction location combining their energies into a single TE.sub.10 output.

Abstract: Apparatus for exciting electrodeless lamps. A magnetron for generating electromagnetic energy in the microwave region includes an extension for its antenna terminal. The extension extends the length of the antenna to control the phase of loading on the magnetron. A circular ground flange and perforated screen enclose the electrodeless lamp, permitting microwave energy to excite the gas within the lamp, while confining the energy to the space bounded by the perforated screen and cylindrical ground flange. The extension for the antenna has a length which maintains the reflection coefficient phase to a level which does not adversely disturb the magnetron operating frequency.

Abstract: Plasma wave tubes are disclosed having waveguide injection systems configured for injection of an RF signal to prebunch the electron beam of the tube and thereby control the frequency of an RF output signal. Preferred embodiments of the injection system include a plurality of rectangular waveguides arranged radially about a cylindrical waveguide member and joined to it for communication with its interior. Plasma wave tubes (140) are also disclosed that utilize the injection system as a collector (44C) to couple an RF output signal from the tube.

Abstract: An excimer lamp utilizing a high pressure fill. The fill includes a halogen at an operating pressure of greater than about 350 torr or the combination of a halogen and a rare gas at a total operating pressure of greater than about 2.5 atmospheres.

Abstract: A plasma asher which obviates microwave leakage and attendant problems by providing a microwave trap proximate the opening through which the plasma tube exits the microwave cavity.

Abstract: An electrodeless high intensity discharge lamp includes a lamp capsule containing a fill material for emitting radiation upon excitation by high frequency electromagnetic energy, a plurality of applicators spaced around a lamp capsule for nonresonant coupling of high frequency energy to the lamp capsule, a high frequency source for supplying high frequency power, and a power splitter and phase shifter for coupling high frequency power from the source to the applicators such that an electric field applied to the lamp capsule rotates at the frequency of the source. The applied high frequency energy is distributed over the lamp capsule so that the tendency for lamp envelope hot spots is reduced. Preferably, four helical couplers are spaced at 90.degree. intervals around the lamp capsule. The high frequency power applied to adjacent applicators is shifted in phase by 90.degree..

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: A method of generating high-power microwaves from a compact source is disclosed by which a transmission line cavity resonator is charged to a high voltage and an electrical switch in the resonator is closed very quickly to produce subnanosecond current risetime and a resultant high-power microwave pulse. Structure to accomplish the method is also disclosed.

Abstract: An extended interaction output circuit is provided for interacting with a modulated electron beam and for outputting RF electromagnetic energy. The circuit comprises a plurality of linearly disposed cavities having an axially extending beam tunnel to permit the traveling therethrough of the modulated electron beam as well as to couple electromagnetic energy between the successive cavities. Each of the cavities is separated by an annular disk having a hole providing the axial beam tunnel. The hole diameters increase in steps so that the impedance of the successive cavities decreases along the axial extent of the circuit. The diameter of the successive cavities is also increased as the associated width is decreased to maintain the same mid-band resonant frequency. The linearly disposed cavities act as an RF filter having successively tapered impedances to reduce reflections of the electromagnetic energy propagating through the circuit.

Abstract: A leaky wall filter for use in an EIK comprises a plurality of guidelets intersecting perpendicularly with a wall of an output waveguide of the EIK. The guidelets would propagate 2.pi. mode oscillation frequencies from the EIK out of the output waveguide. A load matched to the 2.pi. mode disposed at the end of the guidelets provides termination for the 2.pi. mode oscillation frequencies and prevents the initiation of oscillation. The load comprises a plenum disposed at an end of the guidelets opposite to the output waveguide, a window having a first surface within the plenum, and a water load provided at a second surface of the window. The 2.pi. mode oscillation frequencies propagating through the guidelets are impedance matched by the window and coupled into the water load for termination. Since a portion of the operating frequency power also leaks through the guidelets into the plenum due to insertion loss, this combined RF power also couples into the water load and is converted into thermal energy.

Abstract: A capacitive stub for adjusting an impedance level of an output gap of a klystron is provided. The klystron includes an iris coupling RF power from the klystron to an output waveguide. The capacitive stub extends from an inner surface of the output waveguide into a position generally adjacent at least a portion of the iris. The stub is capable of adjustment from external to the output waveguide to vary the position of the stub relative to the iris, and in so doing, change the capacitance of the iris. By changing the iris capacitance, the impedance of the output gap can be altered.

Abstract: An illumination unit of the invention comprises an electrodeless low-pressure discharge-lamp (10) and a high-frequency power supply (50). The lamp (10) is provided with a gastight closed discharge vessel (20) with an ionizable fill (21). The lamp (10) further is provided with a coil (30) with turns (31,32) of a primary and a secondary winding (33,34). The power supply unit 50 is provided with input terminals (51a,51b) and is further provided with a first output terminal (52a), electrically neutral with respect to mass, that is connected to a first end (36a) of the primary winding (33) and with a further output terminal (52b) that is connected to a second end (36b) of the primary winding (33).

Abstract: Apparatus for coupling electromagnetic energy to electrodeless lamps. A waveguide having one end connected to a source of electromagnetic radiation was closed at the second opposite end. A coupling device at the second end couples microwave energy from the waveguide to an electrodeless lamp. The coupling device includes a coaxial transmission line having a center conductor extending through one of the walls of the waveguide adjacent the second end. An alcove partition within the waveguide contacts the extending conductor and forms an alcove in the waveguide. The alcove portion provides for an impedance matching structure between the transmission line and waveguide. The electrodeless lamp which is positioned above the free end of the coaxial transmission line is excited with the coupled microwave energy.

Abstract: A device for charging PFLs (Pulse Forming Lines) on a time scale of a few nanoseconds. The device includes a source transmission line (STL) connected through a switch to a pulse forming transmission line. The source line is initially charged while the PFL is uncharged, and the switch is open. The impedance of the STL is larger than the impedance of the PFL. In operation when the switch is closed, energy flows from the source line to the PFL. As the energy and voltage build on the PFL, an output switch closes and delivers the energy of the PFL to the output transmission line section. The impedance of the output transmission line section is matched to the PFL impedance so that all of the energy in the PFL flows into the output section in the form of a pulse.

Abstract: A push-pull Class E amplifier is used to provide an efficient transfer of power to the induction coil in an electrodeless discharge lamp and to minimize the amount of radio frequency interference emitted by the lamp into the surrounding environment.

Abstract: A body of dense plasma is established within a short drift tube of a klysn amplifier between input and output resonator cavities thereof to support current modulation of microwave energy by interaction with an electron beam propagated through the drift tube. The plasma is confined to a column radially spaced from the electron beam for two-stream interaction enabling enhancement of current modulation under simultaneous high-power and high frequency operation.

Abstract: A fluorescent lighting system that includes a gas containment vessel having an internal phosphor coating and containing an ionizable gas, field concentrator electrodes supported inside or outside the gas containment vessel, and an RF power source coupled directly or capacitively to the field concentrator electrodes.

Abstract: An electrodeless discharge lamp includes a single type auxiliary electrode for preliminary discharging, disposed on or adjacent to outer peripheral wall of lamp tube at a position for being electrostatically coupled to interior space of the tube, and supplied with a power from a second high frequency power source other than a first high frequency power source supplying a high frequency power to a main induction coil on the tube, whereby the lamp is made to attain an excellent startability without requiring any large size high frequency power source.

Abstract: A microwave powered discharge device which utilizes a TM.sub.NMO cavity. A conductive body is positioned at a null in a discharge device which utilizes a TM.sub.210 cavity to reduce direct coupling from the microwave coupling means, e.g., slot of the cavity. A plurality of TM.sub.110 cavities are ganged together, and a single discharge tube extends through all of the cavities.