Abstract: A discharge tube arrangement comprises an excitation device and a discharge tube made of a light-transmissive dielectric material and containing a fill. The excitation device is suitable, when energized with radio frequency (r.f.) power, for exciting surface waves in the discharge tube. The excitation device includes a launcher and a plurality of electrical components associated with the supply of r.f. power to the launcher and constituting at least one of an impedance matching network and a part at least of means to generate r.f. power. This plurality of electrical components is positioned in the launcher between its inner and outer tubes.

Abstract: A discharge tube arrangement includes a discharge tube containing a fill and means for generating a discharge in the fill from a source of radio frequency (r.f.) power. An electrically conductive structure surrounds the discharge tube. The electrically conductive structure is formed of a plurality of waveguides which extend outwardly from the discharge tube. One or more waveguides has a cross-sectional area that increases with separation from the discharge tube. Each waveguide is dimensioned to support the propagation of electromagnetic radiation above a cut-off frequency.

Abstract: A discharge tube arrangement for use as a light source includes a discharge tube made of a light-transmissive dielectric material and containing a fill. An excitation device for exciting surface waves in the discharge tube comprises an r.f. power generator and a launcher. The launcher is formed as an inner tube, an outer tube coaxial with the inner tube and first and second end walls, at least one of the first and second end walls having an aperture for receiving the discharge tube. A launcher gap extends axially from a first end of the inner tube and there is also a further gap. The outer tube and the first and second end walls form an unbroken electrically conductive path to provide an r.f. screening structure around the inner tube.

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 starting circuit for an electrodeless high intensity discharge lamp comprises a high efficiency power supply for providing a radio frequency signal to a starting probe disposed proximate the arc tube of the lamp. The power supply may comprise either a Class-D or Class-E power amplifier having an output resonant circuit tuned to a substantially higher frequency than the operating frequency of the signal provided to the excitation coil by the lamp ballast to ensure minimal interaction between the starting circuit and the ballast. The output resonant circuit includes an inductance coupled in series with a capacitance that preferably comprises the capacitance between the excitation coil and the starting probe. After initiating the arc discharge, the starting circuit is deactivated.

Abstract: A protective coating of suitable composition and thickness is applied to the inner surface of the arc tube of a high-intensity, metal halide discharge lamp in order to avoid a substantial loss of the metallic component of the metal halide fill and hence a substantial buildup of free halogen, thereby extending the useful life of the lamp. A preferred lamp structure includes a fused silica arc tube with a silicon coating. The silicon coating is preferably applied to the arc tube using a chemical vapor deposition process.

Abstract: Arc lamp output stability is improved by use of negative feedback which stabilizes arc position and intensity. Position and intensity of an image of the arc are sensed by optical sensors to control electromagnets which shift arc position so as to decrease wander and to control lamp current to decrease arc intensity variation.

Abstract: A starting circuit for an electrodeless HID lamp provides a two-stage resonant starting signal to a gas probe starter of the type comprising a starting chamber which contains a relatively low-pressure gas and is attached to the outer wall of the arc tube. The starting circuit comprises a resonant LC circuit of variable impedance including the series combination of a variable inductance and the parasitic capacitance between the gas probe starter and the excitation coil. In operation, the resonant circuit is tuned to a predetermined value so that, upon application of an RF signal to the excitation coil, resonant operation of the starting circuit results in the application of a sufficiently high starting voltage to the starting chamber to ignite a low-current glow discharge therein. Once the glow discharge is ignited, the starting circuit is retuned to ensure that a sufficiently high starting voltage is capacitively coupled to the arc tube to ionize the arc tube fill and initiate an arc discharge therein.

Abstract: A ballast for an electrodeless high intensity discharge lamp comprises a Class-D power amplifier including an integrated tuning capacitor network and heat sink. A series blocking/tuning capacitor and a parallel tuning capacitor are integrated by sharing a common capacitor plate. The metal plates of the parallel tuning capacitor also comprise heat sink planes to remove excess heat from the excitation coil of the lamp. Heat sink fins are affixed to the plates of the parallel capacitor. Efficiency is maximized by matching the impedance of the ballast load network.

Abstract: A diode pulser is described which comprises a diode and an inductor connected in series, the impedance of the diode being controllable to suddenly increase the impedance to produce a high voltage pulse across the diode. The diode can include a pair of spaced electrodes (12, 14 in FIG. 2) forming a gap between them across which electrons move when a voltage is applied. To increase the impedance, a magnetic field (38) is suddenly applied parallel to the electrode surfaces, to bend the electron paths so as to require a much higher voltage to move the electrons across the gap, the inductor (26) creating such voltage to maintain the current flow for a brief time. The diode pulser is useful as a rapid-acting switch, and as a source of high energy electrons that are useful to generate X-rays, microwaves, and for other purposes.

Abstract: A starting aid for an electrodeless high intensity discharge (HID) lamp comprises a spiral starting electrode which, at least during lamp starting, conforms to the shape of the arc tube so as to provide a relatively high capacitive starting current upon receipt of a radio frequency starting signal, resulting in a rapid transition from a glow discharge to a high intensity solenoidal discharge. At least one turn of the spiral starting electrode is preferably in contact with the portion of the arc tube nearest the arc discharge to be formed and is oriented so as to provide a capacitive starting current that flows in substantially the same location as the arc discharge to further ease lamp starting. In one embodiment, the spiral starting aid comprises first and second coil portions. The first coil portion conforms to the shape of the arc tube and has at least one turn disposed nearest the portion of the arc tube where the arc discharge is to be formed.

Abstract: An excitation coil for a high intensity discharge lamp has an optimized configuration for maximizing efficiency and minimizing output light blockage. The coil includes a conductive surface having a shape which corresponds to rotating a bilaterally symmetrical trapezoid about a coil center line in the same plane as the trapezoid without intersecting the center line. The conductive surface is disposed on a conductive core for efficient heat removal from the coil, resulting in reduced coil losses. In one embodiment, the coil cross section is increased by adding a rectangular portion to the trapezoidal portion, thereby extending the coil outwardly from the coil center line so as to remove heat from the coil more quickly without affecting light output from the lamp.

Abstract: An integrated light source for use in a large scale video display. The light source includes a cylindrical housing containing at least one electrodeless fluorescent lamp and a circuit for starting and operating the lamp. The circuit includes a radio-frequency generator whose output is capacitively coupled to the electrodeless lamp by means of a pair of coupling members mounted adjacent the exterior surface of the lamp's envelope. A strong electric field produced between the coupling members is sufficient to cause breakdown and excitation of the electrodeless lamp fill material. In a preferred embodiment, a circuit coupled to the input of the radio-frequency generator controls operation of the lamp in response to a low voltage control signal. The integrated light source of the present invention overcomes problems in the prior art of premature lamp life due to failures of the electrode or the glass to metal seal.

Abstract: A plasma switch employs a cold cathode which yields secondary electrons to sustain a plasma within the switch. The cathode is provided with a series of perturbations which increase the effective cathode surface area exposed to the plasma and increase the average effective path lengths of secondary electrons emitted from the cathode and the probability of such electrons having ionizing collisions with gas molecules within the switch. The interior cathode surface is provided with a coating formed from chromium or a chromium mixture. Chromium combines a high rate of secondary electron emission with low sputtering and other advantageous properties for plasma switch operation. Various types of chromium-plated perturbations are described.

Abstract: A video display for use in conveying information as, for example, in a sports stadium. The video display includes a plurality of electrodeless lamps mounted in a metallic housing which is defined by a back wall and a front wall. The front wall is provided with a plurality of holes formed therein and is spaced from the back wall by means of side walls. An electrodeless lamp is located within each of the holes in the front wall and is surrounded by a cylindrical wall formed in the front wall. One end of each lamp is in proximity to a conductive plate which is formed to provide an equipotential surface to the lamps. Radio-frequency (RF) energy of from 10 to 100 megahertz is coupled from an external RF power supply to the housing. A strong electric field produced between the portion of the conductive plate in proximity to one end of a lamp and the cylindrical surface surrounding the lamp is sufficient to cause breakdown and excitation of the electrodeless lamp fill material.

Abstract: An illuminated aerial marker for a high voltage transmission line using a spherical colored opaque capacitor with gas filled lamps electrically connected, exterior to the capacitor with one electrode of the lamps connected to the high voltage source and the other to the conductive area of the capacitor or capacitors. The lamps are spaced and sized to provide illumination with nighttime conspicuity of at least 4,000 feet when the lamps are activated.

Abstract: An electrodeless lamp system and method for providing light output having a controlled spectral distribution. A lamp having a fill which is not fully vaporized at the lamp operating temperature and which emits in a characteristic region of the spectrum is used. A function generator generates a function signal, and the magnitude of the lamp output in the characteristic region or the ratio of such magnitude and a magnitude in a different characteristic region is compared with the function signal. The difference signal is used to control the amount of cooling gas which is incident on the lamp bulb to control the spectral distribution of the radiation which is emitted by the lamp.

Abstract: An electrodeless lamp which couples strong microwave fields to a very small bulb of diameter about 1/2' or smaller. The lamp is operated in a mode which is independent of the height of the cavity and which provides electric field lines parallel to such height. The height of the cavity is substantially reduced as compared with prior lamps to provide strong coupling of the electric field to the bulb.

Abstract: Improved efficacy and color rendition are achieved in a high intensity discharge, solenoidal electric field (HID-SEF) lamp by using a novel combination of fill ingredients, including lanthanum halide, sodium halide, cerium halide, and xenon or krypton as a buffer gas. The preferred lamp structure is that of a short cylinder having rounded edges in order to achieve isothermal lamp operation and further efficacy improvement.

Abstract: Electrodeless low-pressure discharge lamp having a lamp vessel which is sealed in a gas-tight manner and which is filled with a metal vapor and a rare gas and which has a core of a magnetic material. During operation of the lamp an electric field is generated in the lamp vessel by means of a winding surrounding the core and a high-frequency supply unit connected thereto. A transparent electrically conducting layer is present on the inside of the lamp vessel, and is connected to an electric conductor located outside the lamp vessel by means of a lead-through member incorporated in the wall of the lamp vessel. The lead-through member is electrically connected to a contact strip of conducting material extending on at least the greater part of the circumference on the inside of the lamp vessel and is electrically connected substantially throughout its length to the transparent conducting layer.

Abstract: A two-phase fluid is injected into a volume upstream of the spark gap flow channel of a spark switch. The injected two-phase flow can be separated, causing the liquid component of the two-phase fluid to form a layer adjacent the wall of the flow channel and a predominately gas phase region near the spark switch electrodes. This distribution of liquid and gas phases can be achieved by tangential injection of the two-phase fluid. The resulting two-phase flow absorbs the thermal and radiant energy produced by the spark in the spark channel, as well as the energy of the shock wave systems produced by the spark in the spark channel, thereby reducing the temperature that the wall of the spark gap would attain without such two-phase fluid flow injection. Vaporization of the liquid due to this energy absorption generates a substantial gas flow which increases the purge flow and recovery rate of the spark gap switch.

Abstract: An electric-arc device has two aligned electrodes separated by an arc gap. The position of an electric arc in the arc gap is stabilized by using at least two coils, each made as a rectangular loop and bent around a cylindric surface. The coils are mounted around the electrodes such that their arcuate sides form two respective circumferences whose centers lie on a line parallel to the axis of the electrodes. The length of the straight side of each coil is no less than the length of the arc gap. The coils are connected to a power supply such that currents flowing along the adjacent straight sides of the neighboring coils are oppositely directed. These opposing currents induce a magnetic field into the arc gap which controls the location of the electric arc.

Abstract: The electrodeless low-pressure discharge lamp comprises a discharge vessel (1) having an inwardly extending protuberance (2) and an evacuated outer bulb (5) having a protuberance (6) projecting into the protuberance (2). A soft magnetic body (3) is arranged in the protuberance (6). It is a heat-resistant envelope (22) and is surrounded by an electrical coil (4) outside the envelope (22).

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 spark gap chamber to promote mixing and/or translation of hot residue gases into the surrounding gases in an unpurged spark gap chamber. The shock (and expansion) waves are reflected from walls and other structures within the spark gap chamber to cause the hot residue gases formed by a spark between the electrodes in the spark channel to mix with the unheated gases found elsewhere in the spark gap chamber. The spark gap chamber walls can be symmetric and shaped to cause the reflected shock wave to converge simultaneously on the spark channel or to focus on different portions of the spark channel at different appropriate times. Alternatively, the spark gap chamber walls can be asymmetric with respect to the spark channel and can force the hot residue gases away from the spark channel.

Abstract: Ignition of high intensity discharge (HID) lamps can be enhanced by the application of ultrahigh frequency (UHF) electric fields at modest power levels. The implementation of UHF power assisted starting offers considerable advantage over known prior art lower frequency power starting methods. Solid state circuits and coupled means can be utilized as described therein.

Abstract: An electrodeless lamp which couples to a small bulb and obtains a relatively high light output therefrom. A cavity which comprises a compound resonant structure including vestibule and reflector portions is provided. The combination of vestibule and reflector results in a condition of resonance throughout the cavity, whereby strong fields are coupled to the small bulb and a reflector is provided for directing and enhancing light output.

Abstract: Disclosed is an apparatus for stabilizing the light output of a high pressure discharge lamp comprising a coil generating a magnetic field acting upon the arc of the high pressure discharge lamp, an arc position detector detecting deviation of the position of the arc, and a magnetic field control circuit controlling the coil in response to the deviation detection output signal of the the arc position detector thereby setting right the position of the arc of the high pressure discharge lamp.

Abstract: An illuminated aerial marker for a high voltage transmission line using a spherical colored opaque capacitor with neon lamps in series or series/parallel or parallel, exterior to the capacitor with one electrode of the lamps connected to the high voltage source and the other to the conductive area of the capacitor or capacitors.

Abstract: A discharge reaction apparatus utilizing dynamic magnetic field for subjecting the surface of an object to a depositing or an etching process is disclosed. The apparatus comprises a member for generating dynamic magnetic field along the surface of an electrode and a member for limiting or forbidding the circulating motion of electron around the electrode.

Abstract: An excitation coil, for stimulating a high-intensity-discharge plasma in an electrodeless discharge lamp, has at least one turn of a conductor arranged generally upon the surface of a toroid with a rhomboid or V-shaped cross-section, which is substantially symmetrical about a plane passing through the maxima of the toroid. The major radius of the coil is such that the lamp is insertable into the coil so that the coil induces a co-planar toroid plasma discharge arc in the lamp, when the coil is connected to a radio frequency (RF) power source.

Abstract: An opening switch for very high power electrical pulses uses a slow magnetic field to confine a plasma across a gap between two electrodes. The plasma conducts the electric pulse across the gap while the switch is closed. A magnetic field generated by the pulse repels the slow magnetic field from the negative electrode to push the plasma from the electrode, opening the switch. A plurality of radial vanes may be used to enhance the slow magnetic field.

Abstract: A large volume magnetoplasma is created by (a) establishing a plasma in an electrically isolated, tubular cavity formed by a cylinder (10) containing a source of ions and electrons at low pressure, into which rf energy is coupled by an antenna (32) alongside the cavity; and (b) allowing the plasma to extend into an adjoining auxiliary region (20) which is connected to the cavity (10). Preferably the operating conditions in the cavity (10) are such that the production of atomic species in the plasma is enhanced. The enhancement occurs when the operating conditions satisfy the relationships ##EQU1## where W is the power in watts applied to the antenna (32), D is the diameter of the plasma cavity (10) in cm, p is the pressure in the cavity (10) (and in the auxiliary region (20)) expressed in millitorr, f is the frequency of the rf power in MHz, L is the length of the antenna (32) in cm and B is the magnetic field in the cavity (10), established by a coil (13) which surrounds the cavity, expressed in gauss.

Abstract: Improved efficacy and color rendition at white color temperatures is achieved in an electrodeless metal halide arc discharge lamp with a novel combination of arc tube fill materials, including sodium halide, cerium halide, and xenon. A preferred lamp structural configuration imparts further efficacy improvement at higher lamp operating temperatures and isothermal lamp operation.

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: A plasma jet ignitor apparatus for generating plasma from a plasma medium such as hydrogen and for discharging the plasma as a jet into the combustion chamber of an internal combustion engine. The apparatus has a plug which has an electrode from which a high energy spark is generated. The spark causes hydrogen which is introduced into the plasma generation cavity by a fuel line to become plasma. The plasma generation cavity is defined by magnetic field generation means. The cavity has an inlet opening adjacent the plasma generation location and an outlet orifice. The plasma is ejected as a plasma jet from the cavity from the orifice. The magnetic field generation means is disposed as a magnetic field coil wound about the cavity. The magnetic field is charged by the discharge of a capacitor at the time of the formation of the plasma in the cavity. The magnetic field accelerates the plasma out of the cavity through the orifice so that the plasma exits as a high velocity jet and achieves effective penetration.

Abstract: The invention relates to an apparatus usable for ionizing a gas comprising a cathode serving as a hot or cold cathode and to a process for using this apparatus. The apparatus includes a facing cathode and anode, the gas to be ionized successively traversing the cathode and the anode. The apparatus is characterized in that the cathode is formed by a first and second cylindrical half-electrode in face-to-face relation, the gas to be ionized passing between the half-electrode and a conductive filament connected by a first end to the first half-electrode and by a second end to the second half-electrode and located between the half-electrodes. The invention applied to all apparatuses used for ionizing a gas, such as electric arcs, unoplasmatrons and duoplasmatrons.

Abstract: A microwave powered electrodeless light source in which a relatively high power level is coupled to the bulb. This is accomplished by arranging for a plurality of energy modes which are substantially de-coupled from each other to be present in the microwave cavity.

Abstract: A DC-AC converter for igniting and supplying a low-pressure discharge lamp, e.g. an electrodeless low-pressure gas discharge lamp. The converter has two input terminals (9, 10) for connection to a d.c. voltage source. The input terminals are connected to a series arrangement controlled semiconductor switching element (12), a first coil (14) and a parallel circuit having the discharge lamp 15 in one of its branches. The control electrode and a main electrode of the controlled semiconductor switching element are connected together by means of a secondary winding (21) of a transformer (17) having a primary winding (16) that forms a part of the parallel circuit. The converter includes a starter circuit comprising a resistor (28) connected between a main electrode and the control electrode of the semiconductor switching element and a capacitor (29) coupled between the control electrode and one end of the secondary winding (21) of the transformer.

Abstract: A triggerable opening switch for a very high voltage and current pulse includes a transmission line extending from a source to a load and having an intermediate switch section including a plasma for conducting electrons between transmission line conductors and a magnetic field for breaking the plasma conduction path and magnetically insulating the electrons when it is desired to open the switch.

Abstract: A shutter (36) is provided for controlling a beam, or current, of charged particles in a device such as a thyratron (10). The substrate (38) defines an aperture (60) with a gap (32) which is placeable within the current. Coils (48) are formed on the substrate (38) adjacent the aperture (60) to produce a magnetic field for trapping the charged particles in or about aperture (60). The proximity of the coils (48) to the aperture (60) enables an effective magnetic field to be generated by coils (48) having a low inductance suitable for high frequency control. The substantially monolithic structure including the substrate (38) and coils (48) enables the entire shutter assembly (36) to be effectively located with respect to the particle beam.

Abstract: An applied-B field extraction ion diode has uniform insulation over an anode surface for increased efficiency. When the uniform insulation is accomplished with anode coils, and a charge-exchange foil is properly placed, the ions may be focused at a point on the z axis.

Abstract: A projector lamp comprising a single ended metal halide discharge lamp in a generally spherical reflector has been found to exhibit turbulence when running. The resulting fluctuation of light especially when used in conjunction with the reflector to concentrate the light for studio or theatre applications provides an apparent movement which is extremely disturbing to the eye. It has been found the turbulent movement of gas around the electrodes in the lamp envelope can be regularised by the application of a magnetic field to the envelope. The turbulence is sensitive to conditions within the discharge arc tube and the strength and position of the magnetic field has to be variable to cater for this. The magnetic field is conveniently applied by an electro-magnet using lamp current.

Abstract: A re-entrant, low-pressure, electrodeless lamp apparatus includes two identical re-entrant center conductors driven in quadrature, resulting in a matched lamp input impedance in both the off and on states nearly independent of incident microwave power.

Abstract: An electrodeless low-pressure discharge lamp having a lamp vessel (1), a core (3) of magnetic material, a first winding (7) arranged to surround the core and connected to a high-frequency supply unit (4), one of the lead-in wires of this winding being electrically connected to a lead-in wire of a second winding (11) with a free end (12), while during operation of the lamp the potential drop between the ends of the second winding is substantially equal to the potential drop between the ends of the first winding and the potential drops in the two windings vary in opposite senses. Interference currents at the supply mains to which the lamp is connected are then strongly suppressed.

Abstract: An electrodeless metal vapor discharge lamp comprising a lamp vessel (1) which is sealed in a vacuum-tight manner and is further filled with a rare gas, which lamp is provided with a core (4) of magnetic material, in which a high-frequency magnetic field can be induced by means of an electric supply unit (7) and a winding (5) arranged to surround the core, an electric field being produced in the lamp vessel (1), the surface area of a cross-section orthogonal to the axis of the winding lying between 20 mm.sup.2 and 60 mm.sup.2, the lamp vessel (1) containing as rare gas krypton and/or argon at a pressure of at most 100 Pa, and the axial length of the winding lying between 8 and 15 mm.

Abstract: An electrodeless lighting system (10) is provided for converting electromagnetic energy whose spectrum is within the ultraviolet bandwidth into energy within the visible bandwidth of the electromagnetic spectrum through excitation of fluorescent composition coatings (20). The lighting system (10) provides for an excitation mechanism (12) which generates an enclosed magnetic field, an induced electrical field, and a radiating electrical field, where the induced electrical field is substantially parallel and in the same direction as the magnetic field. Both the magnetic and induced electrical fields are applied at substantially the same frequency for accelerating and directing electrons for collision with gas composition atoms contained within a closed contour gas housing (14) and in particular within a gas housing chamber (16). An electrostatic shield (26) substantially encompasses the excitation mechanism (12) is provided for containing the radiating electrical field within the lighting system (10).

Abstract: In a microwave discharge light source apparatus for effecting discharge of an electrodeless discharge lamp held in a cavity which causes resonance by microwaves, the wall surface of the cavity resonator is constituted by a mesh and wires constituting the mesh, are electrically connected at each crossing point without resistance of contact. Effective discharging of the lamp is attainable and the cavity has a mechanically strengthened structure.

Abstract: An electrodeless low-pressure discharge lamp comprising a lamp vessel (1) sealed in a vacuum-tight manner and filled at least with a metal vapor and a rare gas, the lamp being provided also with a cylindrical core (2) of magnetic material, such as ferrite, a winding (4) arranged to surround the core (2) and an electrical supply unit connected thereto for producing during operation of the lamp an electrical field in the lamp vessel (1). The supply unit is located in a thin-walled metal housing (8) provided in a wall portion (9) of synthetic material, which is partly of conical shape and is provided at its end with an Edison lamp cap (10), and the core (2) accommodates a rod-shaped or tubular body (11) of thermally conducting material connected to the housing (8). In order to improve the ignition properties of the lamp, an electrical insulator (12) is provided between the end of the body (11) and the wall of the housing (8).

Abstract: An electrodeless low-pressure gas discharge lamp includes a glass lamp vessel (1) which is provided with a sealing member (6) connected to the wall of the lamp vessel by means of a suitable sealing material, and which has on its inner wall a conductive layer (7), at least part of which is transparent, that extends beyond the connection to the sealing member (6), the member being slightly recessed into the lamp vessel. The inner conductive layer can thus be connected in a simple manner to an electrical conductor, which during operation of the lamp is connected, for example, to one of the supply wires of the mains.