Abstract: A method and apparatus for efficiently driving a load coupled to a ballast is described. A switching element coupled between a pair of ballast terminals converts a low frequency drive signal to a high frequency drive signal which is provided to the load.

Abstract: A capacitor network includes a plurality of capacitors in series. Each capacitor has a preselected capacitance and breakdown voltage. The sum of the breakdown voltages of all the capacitors is at least equal to a desired voltage value. The capacitances of the capacitors are chosen to provide a desired capacitance value when connected in series. At least one capacitor has a break-down voltage equal to greater than fifty percent of the desired voltage value and a capacitance approximately equal to the desired capacitance value.

Abstract: An improved ballast circuit for use with a compact fluorescent lamp includes an EMI filter, a rectifier and voltage amplification stage, an active resonant circuit and power factor correction stage which is connected in parallel to a lamp load. The ballast circuit includes a feedback capacitor which provides a feedback path for a portion of the high frequency current to the rectifier and voltage amplification stage. The feedback capacitor of the improved ballast circuit reduces the non-linear characteristics of the diode, thus providing almost a linear load on the input power supply and therefore achieving an improved power factor, on the order of 0.95 or greater. The improved ballast circuit may also include a dimming stage which works with the active resonant circuit to vary the amount of power that is supplied to the lamp load. The dimming stage does not require the addition of parasitic active stages and thus provides a lamp with high electrical efficiency.

Abstract: An electrodeless fluorescent reflector lamp includes a housing arrangement having a threaded screw base for receiving line power and a lamp envelope mounted on the housing arrangement. A ballast circuit is disposed within the housing arrangement and is effective for converting line power into an RF signal which excites a fill contained within the lamp envelope to a discharge state thereby resulting in the production of visible light. The lamp envelope is constructed having an upper curved face portion and a lower tapered portion which extends partly within the housing. A reflective coating is applied to the lower tapered portion of the lamp envelope. A phosphor coating distribution is applied to the interior surface of the lamp envelope in a manner so as to maximize the light output from the reflector lamp.

Abstract: Halogen bulb without additional safety device for high-volt/intermediate-t operation with a bulb pinched on one side produces an inherent safety effect by producing a current lead segment that is pinched from an uncoiled wire with a diameter of 130 .mu.m at most and the distance between the two current leads is suitably selected.

Abstract: A compact fluorescent lamp adapter for compact fluorescent lamp includes a ballast case which has a lower plate having a compact fluorescent lamp socket and an upper plate having an incandescent lamp base, the upper plate being coupled to the lower plate. The compact fluorescent lamp socket formed in the lower plate has a plug retaining portion for receiving a compact fluorescent lamp plug, a PCB having a plug through hole for accommodating a plug retaining portion of the compact fluorescent lamp socket, and having a fluorescent lamp ballast circuit. The compact fluorescent lamp socket comprises at least two terminals having ring contact portion to be contacted fluorescent lamp plug pin and elastic contact portion to be contacted with contact pad formed on the PCB, and a terminal settling plate for settling said terminals onto pin through holes respectively formed in said lower plate.

Abstract: An apparatus for generating negative ions includes two casings which are coupled each other and respectively have an outer thread on one end thereof, a lid which is fastened to the coupled casings, an electrode rod disposed within the coupled casings, an electrode plate disposed within the coupled casings, a circuit board which is disposed within the combined casings and connected to the electrode rod and the electrode plate and having at least one high voltage discharging plate, a high voltage generator which is connected to the circuit board and the high voltage discharging plate, and a plurality of ventilation slots which are respectively defined in the casings and the lid, such that the apparatus can be easily assembled, installed and utilized as an independent unit.

Abstract: A discharge lamp lighting device in which the effects of heat generated by a discharge lamp on a noise filter circuit are reduced and a sufficient installation space for the noise filter circuit is provided. The discharge lamp lighting device includes a starter circuit which generates a start signal for a discharge lamp and applies the start signal to the discharge lamp, and a noise filter circuit which is interposed between the starter circuit and discharge lamp. The noise filter circuit is disposed in a mounting member for mounting the starter circuit, or otherwise the noise filter circuit can disposed in a mounting member for mounting therein a transformer which is included in the starter circuit and is used to generate a start signal for the discharge lamp.

Abstract: A housing having a cavity is in sealing engagement with a glass jewel which also contains a cavity; these two cavities cooperate to form a closed chamber. A frame supporting terminal plates is mounted within the chamber. The frame also mounts a circuit board which in turn mounts a plurality of LEDs. An encapsulating material fills all of the spaces within the chamber.

Abstract: The circuit for firing and supplying a discharge lamp, includes:a load circuit (10), with at least one discharge lamp (L) and a voltage supply for supplying a discharge lamp,a subportion of the circuit is in parallel with the lamp (L). This subportion includes at least one arrangement of capacitors (17, 21) and an inductive impedance which can be varied in a controllable manner in order to modify the value of the total impedance in parallel with the lamp.

Abstract: A design for a field emission device comprising a cold cathode emitter, a control gate and a focus gate, is discussed. The focus gate is connected to the emitter voltage source and a ballast resistor is inserted between this connection point and the emitter. This ensures that the focus gate will always be more negative than the emitter, this difference in potential increasing with increasing emitter current. This leads to a linear current-voltage characteristic for the device and also makes for a tighter electron beam than that provided by designs of the prior art. A physical realization of the design is described along with a cost effective method for manufacturing said physical realization.

Abstract: A variable power lamp control adapter is provided having a novel, different, and a lower cost construction method than that used in prior art lamp control devices. The circuit construction is achieved by utilization of the Surface Mount Technology disciplines of Polymer Thick Film and Chip on Board technologies. The adapter circuitry is constructed and held on a uniquely dissimilar type of substrate than that used in prior art, and assembled into housings that contain unique interengaging mating parts for a more rapid assembly process than the assembly processes used in prior art construction. In the present invention an overall improvement in the organization, arrangement of all componets, housings and assembly is achieved for a reliable power control operation.

Abstract: The invention relates to a single-ended discharge lamp with circuitry in its housing base. The discharge lamp includes a discharge tube and a housing. The discharge tube is provided with electrodes containing a fill and sealed in a gas-tight manner. The housing base contains circuitry mounted on a circuit board and providing for the operation of the discharge tube. The housing base is built from two parts, a base and a cap, fixed to each other. The housing base is formed in a way suitable for mechanical and electrical connection to a lamp socket on one part, and for mechanically fixing the discharge tube and connecting the output terminals of the circuitry to the electrode inleads of the discharge tube on the other part. The circuit board is inserted between supports formed in the inside of and protruding from one part of the housing base. One feature of the invention is that longitudinal ribs are formed on the support and protrude from the support.

Abstract: A spark ignition system and spark plug for utilization in an internal combustion engine combusting an ultra lean fuel/air mixture has capacitors and rectifiers built within the spark plug and the system is constructed to be compact and capable of delivering a controlled spark that has the physical properties of providing a very fast, high power pulse or train of pulses greater than conventional spark plugs.

Abstract: A fluorescent lamp includes a lamp tube having first and second ends and containing fill materials for causing light generation when provided with electrical power. The lamp further includes first and second power-transferring means at the first and second ends of the lamp tube, respectively, for providing the fill materials in the lamp tube with electrical power. Also included is a thermal heat shield separating the first power-transferring means from ballast circuitry which supplies power to the first power-transferring means and which has a lifetime that becomes substantially less as its operating temperature increases. The thermal heat shield is constructed so that it reflects back to the first power-transferring means and any adjacent portion of the lamp tube sufficient radiant energy to reduce the operating temperature of the ballast circuitry by more than about one degree Celsius compared with the absence of the heat shield.

Abstract: A plug has a two-part housing accommodating a printed board with an electrical screening element for preventing propagation of electrical disturbing radiation during the operation of a gas discharge lamp. A mass of a durable elastic material such as silicon is applied on a part of the periphery of at least one screening element between the screening element and the adjoining housing part. The inner space of the housing is filled with a casting mass of an electrically insulating material in which also an elastic mass is enclosed. The elastic mass uncouples the screening element from the housing and from the casting mass, so that a thermal expansion of the screening element is possible and also vibrations of the plug are not rigidly transmitted to the screening element.

Abstract: A display fluorescent lamp comprises; a dielectric cylindrical container having a large-diameter portion in which rare gas is sealed and a small-diameter portion which is almost coaxially connected with the large-diameter portion at one end of the large-diameter portion, the outside diameter thereof being smaller than that of the large-diameter portion; a light emitting portion which is formed at the other end of the large-diameter portion and has permeability; an internal electrode which is inserted into the cylindrical container from the other end of the small-diameter portion which is not connected with the large-diameter portion; a fluorescent substance layer formed on the inside face excluding that in which the light emitting portion is formed, of the large-diameter portion of the cylindrical container; and an external electrode formed on the outside face of the large-diameter portion excluding a portion in which the light emitting portion of the cylindrical container is formed, the length in the axial d

Abstract: Fluorescent type lamps are arranged to have high frequency power derived from standard, commercial A.C. sources either directly or from power levels distributed from a master ballast. When the master ballast is employed, it functions as an interface between the primary power source and a distribution network to one or more modules so as to relieve the modules of operations such as initial power form conversions, filtering and power factor correcting which require large components. The module or modules driven by the master ballast output are contained within the lamp envelope or attached as an extension of the lamp envelope. The module is formed of elements mounted as a miniaturized unit configured to fit within the lamp envelope or to attach to the end of the envelope. The module includes oscillator components mounted on an elongated board so as to form an assembly with a cross-section compatible with the perimeter of the envelope itself.

Abstract: A module including a starter assembly and a fluorescent tube assembly is provided to allow the use of fluorescent lighting in a standard incandescent light bulb socket. The starter assembly is coupled to the tube assembly using a coupling system that includes a support plug which protrudes from the starter assembly and is inserted into a receptacle provided in the tube assembly.

Abstract: A compact fluorescent lamp unit has a phosphor coated bulb of which first and second sealed end portions. A pair of filaments is disposed in the bulb. The filament contains an emitter for enhancing thermionic emission of electrons therefrom and is caused to be cut off by the self-generated heat when the emitter is substantially dissipated. The lamp device has an inverter circuit containing a resonant capacitor disposed between each one end of the filament coils to pass a resonant current through the capacitor during the operation of the lamp. The filament coil is substantially composed of a tungsten wire having a diameter corresponding to 8 MG though 12 MG and is normally operated with a lamp current ranging from 250 mA to 350 mA. The filament coil has a cold resistance ranging from 2 .OMEGA. to 4 .OMEGA. and an output voltage of the inverter circuit exhibits more than 260 volts when the fluorescent lamp is substituted by a resistor having 5 .OMEGA..

Abstract: A lamp cathode-to-ballast interconnect is provided in combination with a lamp having elongated cathodes and ballast circuitry for supplying power to the cathodes. The lamp cathode-to-ballast interconnect comprises a plurality of conductive clips connected to the ballast circuitry. Each clip has a generally flat portion connected at a first end to ballast circuitry and has a pinching groove formed through the flat portion and extending to a cathode-receiving opening at a second end. The interconnect further comprises a loom for holding the lamp cathodes. The loom comprises, for each cathode, a pair of cathode-receiving support grooves separated by a space in which a second end of an associated conductive clip is to be received. Walls of each of the pair of cathode-receiving support grooves grip therein-received portions of the cathode with sufficient force to enable a gas-tight contact to be made with its associated conductive clip when the cathode is received within the pinching groove of the clip.

Abstract: This invention relates to a single-ended discharge lamp having an electric circuitry placed in its base member, which discharge lamp comprises a discharge tube filled with additive and gas, is sealed in a gas-tight manner and is provided with electrodes. A base member is provided for the mounting of the discharge tube and for incorporating the electric circuitry mounted on a printed circuit board therein. The base member has a screw base mounted thereon both for mechanical and electrical connection to a socket. Furthermore, the terminals of the circuitry are fixed and are electrically connected with the electrode lead wires by means of mechanical connector arrangement where the mechanical connector component is one contiguous metal part.

Abstract: A shell form ballast has rounded corners for positioning inside a ballast housing for use with a fluorescent light bulb adapter. The ballast has rounded outer corners to meet both long-term life and power requirements, and spatial design constraints of a fluorescent lamp adapter assembly for use in an incandescent lighting fixture, and particularly for use in a recessed incandescent lighting fixture. The rounded outer corners of the ballast provide the ability for the shell form ballast to fit into a hollow housing for use in the recessed lighting fixture while simultaneously providing the shell form ballast a snug fit in the hollow housing, thereby minimizing gap growth.

Abstract: A lighting system having a gas discharge lamp and a stabilization ballast further includes a low loss device to reduce the current through the ballast and lamp, thereby reducing system wattage for energy savings. For a lead-type ballast, the current reducing device is a capacitive device in parallel with the discharge lamp. For a lag-type ballast, the device is an inductive device in parallel with the lamp. The device may be in a housing connected between the lamp ballast and the lamp, or may be included within the outer envelope of the discharge lamp. This enables an existing system to be easily retrofit without disturbing the existing ballast.

Abstract: A compact dimmable fluorescent lamp includes a dimming control ballast within a base which installs directly on an existing incandescent or other lighting fixture. The lamp mounts a fluorescent illumination element and includes an accessible dimmer control member connected to the dimming control ballast.In the preferred embodiment, a rotatable lamp globe both covers the fluorescent lamp and is coupled to the control element. The globe thus provides the dual functions of decoratively covering the fluorescent lamp tubes and serving as the dimmer control by rotating the globe to vary the amount of power that is supplied to the lamp. In other embodiments, a rotatable external annular ring extends substantially around the circumference of the lamp base and is connected to the dimming ballast control to serve as the dimmer control.

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: An anode for flat display screens, of the type including at least one set of phosphor strips disposed over corresponding conductive strips and at least one interconnection conductor for the phosphor strips. Each conductive strip of each set is connected through a resistor to the associated interconnection conductor.

Abstract: A ballast device for a compact fluorescent lamp, comprises a ballast case including upper case 10-1, a lower case, and PCBs. The upper case has a incandescent lamp base 19 and the lower case has a socket substrate 11 having a compact fluorescent lamp socket. A bottom portion of the upper case is assembled with said lower case having a socket substrate 11. The PCBs includes a first PCB 15 where electronic circuit components 15-2 are mounted on, having a first receiving portion for allowing for the fluorescent lamp socket to be inserted in, and a second PCB 16 where a electronic circuit components 16-2 are mounted, and the mounted components 16-2 having long height are located in center area of the second PCB 16 to be located inside the bulb base 19.

Abstract: A power supply is plugged into an ordinary household electrical outlet and conditionally provides a high frequency current at a power receptacle operative to receive the power plug of an ordinary table lamp; which table lamp has a special fluorescent lamp screwed into its lamp socket. Provided the special fluorescent lamp is indeed screwed into the lamp socket, and provided the lamp's switch is in its ON position, the power supply does in fact supply high frequency current from its power receptacle; which high frequency current powers the special fluorescent lamp at a nominal power level, thereby to provide for high-efficacy luminous output. A storage battery contained within the power supply is kept fully charged by current derived from the power line voltage normally present at the electrical outlet and functions such as to cause high frequency current to be supplied from the output receptacle even if the power line voltage were to be disrupted.

Abstract: A fluorescent lighting system is disclosed which provides for selective lighting of several fluorescent lamps of differing power ratings so as to provide several stages of fluorescent illumination. The ballast transformers of the fluorescent lighting system are supported in at least one ballast transformer support case which is maintained in a spaced apart relationship to at least one fluorescent lamp support case.

Abstract: A ballast device for a compact fluorescent lamp with: a ballast case including an outer case (17) and a socket substrate (11), the outer case having an incandescent lamp base (19) at its top portion, the substrate having a compact fluorescent lamp socket and a bottom portion of the outer case being assembled with the socket substrate; a first printed circuit board (PCB) (15) on which electronic circuit components (15-2) are mounted and having a first receiving cavity (15-1) for allowing the fluorescent lamp socket to be inserted therein; and a second PCB (16) on which other electronic circuit components are mounted, with the latter mounted components, that have a relatively high height, being situated in a center area of the second PCB, thus located within the bulb base.

Abstract: A high power strobe lamp has a multi-pin base, an elongated gas-filled tube having a loop formed therein, an anode in one end of the tube and a cathode in the other end of the tube, and the ends of the gas-filled tube being mounted in the base and connected to the pins. A heat dissipating member extends through the loop and a conductive wire, having opposite ends connected to the pins, is spirally wrapped around the tube ends adjacent to the base and extends through the heat dissipating member.

Abstract: A DC type gas-discharge display panel comprises a plurality of discharge cells; discharge current limiting means provided for each of the discharge cells, for limiting a discharge current of each of said discharge cells; and a filling gas filled into each of said discharge cells, and having an inert gas mixture. A partial pressure ratio of said inert gas mixture to total pressure of said filling gas is at least 0.95. The above-described inert gas mixture is selected from the group consisting of (1) a first gas mixture consisting of a He gas and a Xe gas, (2) a second gas mixture consisting of a He gas, a Xe gas, and a Kr gas, (3) a third gas mixture consisting of a Ne gas and a Xe gas, and (4) a fourth gas mixture consisting of a Ne gas, a Xe gas and a Kr gas.

Abstract: A compact fluorescent lamp having a lamp envelope with a plurality of lamp ends disposed within a housing or base configuration, utilizes an enhanced adhesive material for securing the lamp envelope to the housing or base that is reflective. The adhesive material has a reflective material added thereto that allows for the light typically absorbed or otherwise lost in the housing, to be reflected back out thereby improving the luminous efficiency of such lamp. The adhesive material is also effective for blocking UV radiation from entering the area in which electronic components of the ballast circuit may be disposed.

Abstract: A compact folded fluorescent lamp and a small incandescent lamp are both mounted on an ordinary Edison-type screw-base capable of being screwed into an ordinary lamp socket at which ordinary AC power line voltage is controllably provided. An inverter-type ballast is integrally combined with the base and is operable to power the fluorescent lamp whenever the base is indeed screwed into the lamp socket. The incandescent lamp is powered from the AC power line voltage by way of an SCR whose conduction angle is controlled such as to cause the total light provided from the combination fluorescent-incandescent lamp to remain substantially constant from the very first moment that AC power line voltage is provided at the lamp socket. Thus, when the AC power line voltage is initially provided, the light provided from the incandescent lamp will be at its maximum while the light provided from the fluorescent lamp will be at its minimum.

Abstract: Fluorescent type lamps are arranged to have high frequency power derived from standard, commercial A.C. sources either directly or from power levels distributed from a master ballast. When the master ballast is employed, it functions as an interface between the primary power source and a distribution network to one or more modules so as to relieve the modules of operations such as initial power form conversions, filtering and power factors correcting which require large components. The module or modules driven by the master ballast output are contained within the lamp envelope or attached as an extension of the lamp envelope. The module is formed of elements mounted as a miniaturized unit configured to fit within the lamp envelope or to attach to the end of the envelope. The module includes oscillator components mounted on an envelope board so as to form an assembly with a cross-section compatible with the perimeter of the envelope itself.

Abstract: The present invention provides a base socket that fits into incandescent fixtures and allows one or many "stick" type compact fluorescent lamps to be inserted. The fixture allows the user to insert as many CFL's as desired without changing or rearranging, in any way, the ballast. The ballast circuitry is designed for series or parallel electrical connections of the CFL's. When in series each socket has a bypassing microswitch that provides for electrical circuit continuity.

Abstract: An energy storage circuit employing an energy storage network and a field emission device charge transport switch is provided. Utilization of various configurations of FEDs in the energy storage circuit provides for performance enhancement of addressing of display devices including liquid crystal displays, electroluminescent displays, and cathodoluminescent displays employing FED electron sources.

Abstract: An outboard ballast which allows a compact fluorescent light bulb and its associated ballast to be positioned within a standard table lamp having a standard-size harp. The ballast is divided into separate sections so that the sections and their housing can extend into an area beyond the harp and below the socket of the lamp fixture. A three-way switch circuit is provided to be adaptable with common table lamp fixtures. The configuration of the present invention provides security features.

Abstract: A device and method for establishing and maintaining a gas discharge extending essentially through the entire space between electrodes which face each other. The gas discharge is obtained by providing on at least one of the surfaces of the electrodes facing each other a thin dielectric coating, and applying a suitable current, in the range of from about 50 KHz to about 2 MHz. A high frequency excitation voltage is used, and the thin dielectric coating acts as a capacitor.

Abstract: The invention relates to a high-pressure discharge lamp (2) provided with a discharge vessel (3) and an outer envelope (30) which encloses a space (6). The lamp is provided with an igniter circuit (10) which comprises a voltage-dependent capacitor (8) and a fuse (7). According to the invention, the voltage-dependent capacitor and the fuse (7) are integrated so as to form a single component (18).

Abstract: A fluorescent light source includes a fluorescent lamp having first and second electrodes at or near the ends thereof for capacitive coupling of RF electrical energy to a low pressure discharge within the fluorescent lamp and an RF source having a first output lead electrically coupled to the first electrode and a second output lead electrically coupled to the second electrode. The electrodes include circuitry for inducing an RF magnetic field within the fluorescent lamp in the region of the electrodes. The RF magnetic field improves the performance of the capacitively coupled RF light source by creating an auxiliary inductive RF discharge near the capacitive coupling electrodes. The inductive discharge locally increases the plasma density and the electrode sheath capacitance and provides a reduction in RF voltage across the capacitively coupled fluorescent lamp.

Abstract: An ignitor (118) comprises a body portion (120) connected with an electrical supply cable (122) and an electrode portion (124) removably mounted within the body portion (120). The body portion (120) includes a capacitor defined by an outer, electrically conductive shell (126) of the body portion, and an inner, tubular capacitor plate (134). The inner, tubular capacitor plate (134) is held within the body portion (120) by means of a connector assembly (132) which is held in place by a dielectric potting compound (136).

Abstract: An electrical power supply unit for the supply of low power loads is provided with a capacitor constructed in the form of a flat piece, having a large cross-section and a small height perpendicular to the plane of the large cross-section. This provides a particularly compact construction, in particular when the capacitor and a transformer or choke coil arrangement are accommodated in a common housing, which also enables a correspondingly compact illuminating lamp to be realized.

Abstract: The present invention offers improvement of performance and efficiency of a compact fluorescent lamp by means of a series tuned LRC ballasting circuit. The resonant voltage rise in the circuit is utilized to increase the cyclic crest voltage necessary for lamp ionization. After ionization occurs, lamp current and power are clamped and regulated by the lower Q factor of the tuned circuit. The LRC circuit provides a square wave of voltage across the lamp with considerable reduction in noise and RF ringing. Since it is a tuned circuit, it operates at approximately unity power factor, at lower temperature, and with a net equivalent impedance that provides for maximum illumination, lamp life and efficiency.

Abstract: A single-ended low pressure discharge lamp having an Edison base includes at least one U-shaped fluorescent tube having electrode leads which are connected to a ballast arrangement disposed in a housing base. The housing base has an upper part on which the fluorescent tubes are mounted, a connecting part on which a threaded base is mounted and a supporting part formed between the upper part and the connecting part. Lead-in wires are connected from the ballast arrangement to the threaded base in a manner to facilitate automated assembly of the lamp. A first lead in wire connects to the central portion of the threaded base whereas a second lead-in wire connects to the sleeve portion after first passing through a guided opening formed in the housing base between the supporting part and the connecting part.

Abstract: A press sealed lamp with an internally pressed fuse is disclosed. The filament structure is conveniently formed so the fuse links across a looped section of the initial filament structure. The loop structure provides strength to the fused filament structure prior to sealing. After the lamp is sealed, a portion of the exposed loop is trimmed, thereby limiting the electrical connection to the path through the fuse.

Abstract: A device for reducing the consumption of energy in a fluorescent tube without varying the luminosity of the tube, comprising a partially reflective curved screen having an internal diameter equal to the external diameter of the tube, and a voltage limiter connected to the terminals of the fluorescent tube.

Abstract: An electronic ballast is connected with the AC power line voltage of an ordinary electric utility power line and powers a fluorescent lamp with a substantially sinusoidal current of frequency substantially higher than that or the AC power line voltage. Within the electronic ballast is a half-bridge inverter, whose output voltage exhibits a substantially trapezoidal waveshape. The inverter is powered from a substantially constant DC voltage whose absolute magnitude if substantially higher than the absolute peak magnitude of the AC power line voltage.

Abstract: The invention relates to a high-pressure discharge lamp provided with a discharge vessel which is enclosed with intervening space by an outer bulb fitted with a lamp cap. The lamp is provided with an ignition circuit in which a fuse is included, which is placed in an oxidizing atmosphere.