Abstract: The present invention provides an arc path formed in a lamp body. In accordance with one or more embodiments of the present invention, the lamp body has a plurality of closely spaced, parallel vanes which form an arc path. In one embodiment, the lamp body comprises a bottom and top plate, and a front and back sealing member. The bottom plate may be a flat plate which can be made of quartz or other suitable material. The plate has a plurality of vanes machined into it out to its edges. Alternatively, the vanes may be separate and sealed onto the bottom plate. The top plate is sealed to the bottom plate. The front and back sealing members are sealed to the plates to complete the seal of the lamp body. In another embodiment, the bottom plate is a solid block of quartz or other suitable glass material, which can have the vane pattern machined onto it stopping short of the edges. The solid block is then sealed at the top and outside edges by the top plate, without the need for front and back sealing members.

Abstract: The invention relates to alumino earth-alkali silicate glasses for molybdenum glass fusions in the form of light bulbs, as the outer shell for lamps, in particular for lamps with regenerative halogen cycles at bulb temperatures of from over 550° C. up to 700° C. Surprisingly and contrary to the current expectation it was found that alumino earth-alkali silicate glasses with a water content of 0.025 to 0.042 wt. % meet the requirements for halogen lamp glass and do not display any disadvantages due to the presence of the above impurity for the halogen cycle process at bulb temperatures of between 550 and 700° C. In glasses with a water content of from 0.025 to 0.042 wt. % the water present does not act as an impurity in the sense that it does not disturb the equilibrium between formation and decomposition of tungsten halides. A blackening of the inner surface of the bulb does not occur, or not a greater degree when compared with bulb glasses with a considerably lower water content.

Abstract: A high intensity discharge lamp (10) has an outer envelope (12) having a cup-shaped top (14), a hollow center section (16) and a bottom (18) all aligned along a longitudinal axis (20), the bottom (18) including a flare (22) having a pinch seal (24) with in-leads (26, 28) sealed therein. A mount structure (30) is positioned within the envelope, the mount structure including a frame (32) comprising a spaced-apart pair of side frames (34, 36) extending substantially the length of the envelope (12) and parallel to the longitudinal axis. The side frames (34,36) have middle portions (35,37) carrying an arc tube (38) and a surrounding shield (40), and the side frames further have an upper portion that frictionally engages the inside surface of the cup-shaped top (14), the upper portion comprising two ends (42, 44) extending in a direction normal to the longitudinal axis and having a space (50) therebetween.

Abstract: A structure of fully enveloped miniature lamp bulb for lamp strings suitable for mass production and having any of varied appearances is disclosed. The lamp bulb has two electrode pins with a predetermined distance therebetween and being connected in the glass body thereof to a light emitting tungsten filament, parts of the electrode pins are extended out of the bottom of the glass body for connecting to a conductor pair. A transparent cover having any of various kinds of modeling which are made separately with dies is provided with an assembling hole of a size mating with that of the lamp bulb and extending inwardly for a suitable depth from an end thereof; the miniature lamp bulb connected with the conductors is placed in the assembling hole by assistance of a positioning block, the connecting area is sealed with adhesive agent to complete assembling of the structure.

Abstract: A coating start point is altered to avoid flowing of a sealing resin to an EL element when the sealing resin is pressed and flattened on adhesion of a device substrate and a sealing substrate with the sealing resin interposed therebetween. In a manufacturing method of a display device of the invention which is formed by adhering the device substrate and the sealing substrate with the sealing resin interposed therebetween, when the sealing resin is coated along edges of the device substrate and the sealing substrate, the coating is started on a corner of the substrates as a coating start point and a coating end point is on the same corner as for the coating start point.

Abstract: Flat Light is a light bulb triangular in shape with a flat top, and its brother has a reflecting cover on the bottom to send out more light through the side and top.

Abstract: A circular fluorescent lamp comprises a light-transmitting circular tube, filled with a discharge gas including mercury and a rare gas, having an outer diameter between about 14 mm and 18 mm. A phosphor layer is coated on the inner surface of the light-transmitting circular tube. A stem seals each end of the light-transmitting circular tube air-tightly, and holds a pair of conductive wires. One of the ends of each pair are connected to a filament, and the other of the ends extend outwardly from the circular tube. A lamp base is arranged between the ends of the light-transmitting circular tube so as to rotate slightly around the center axis of the circular tube and includes conductive pins, which are connected to the conductive wires. An insulator, arranged between at least one pair of the conductive wires, limits the movement of the conductive wires. The circular fluorescent lamp may be used for a lighting fixture.

Abstract: A method and apparatus for preventing the formation of leachable mercury in mercury arc vapor discharge lamps which comprises coating at least one of the metallic components of the mercury arc vapor discharge lamps with at least one noble metal coating.

Abstract: A safety switch for a lamp having an outer envelope with a light source capsule mounted therein. The lamp has a base for connection to an electrical circuit via a mating socket and has in-leads appropriately connected to the base and to the light source capsule whereby electrical power can be supplied to the light source. A fuse is operatively mounted to one of the in-leads in the base. The safety switch is mounted in the outer envelope and tensioned thereagainst whereby breakage of the outer envelope causes the safety switch to release and electrically contact the in-leads causing a short circuit and opening the fuse, thereby removing power from the capsule.

Abstract: A pen light bulb which is self aligning in conventional pen light flashlights is disclosed. Applicable pen light flashlights rely upon pressure bearing retention of the bulb therein. A focusing lens protective element of the pen light bulb has various features which provide for a more stable seating surface thereon to contact the housing of the pen light flashlight. These features provide for the axis of projection of the beam of light from the bulb to match, or nearly match, a central axis of the pen light flashlight. A wider and larger spring contact surface on a circular base of the housing of the pen light bulb provides for a truer application of pressure by a spring to the pen light bulb to assist in proper alignment within conventional pen light flashlights.

Abstract: This invention provides a TIR (total internal reflecting) lens to capture and redirect light from multiple light sources, such as neon or fluorescent lamps, to generate a light of uniform brightness across the lens face.

Abstract: A light transmitting container is used to house a cold cathode fluorescent lamp (CCFL) to reduce heat loss and to increase the luminous efficiency of the lamp. An electrical connector configuration is connected to an electrode of the lamp and adapted to be electrically and mechanically connected to a conventional electrical socket. A driver circuit in the container converts 50 or 60 Hz power to the high frequency power suitable for operating the CCFL. At least one of the electrodes of the CCFL is outside of the container to facilitate heat dissipation. A CCFL having an elongated tube portion and enlarged portions for housing larger electrodes is proposed to enhance the longevity and brightness of the CCFL. Larger electrodes are used to generate more electrons in the CCFL, thereby generating more light. Larger electrodes also reduces the temperature of the tube material of the CCFL to enhance the lifetime of the device.

Abstract: A fluorescent lamp includes an end cap 4 and a fluorescent tube 1 that has electrode seals 22 and 23 at its ends. The end cap 4 is made of synthetic resin and is attached to the fluorescent tube 1 by silicon resin 31. The end cap 4 includes round cavities 26 and 27 for holding the electrode seals 22 and 23 and thermal protection element holders 20 and 21 for holding thermal protection elements 16 and 17 adjacent to the electrode seals 22 and 23. Pillars 28 are provided between the thermal protection element holders 20 and 21 and the round cavities 26 and 27 to support the thermal protection elements 16 and 17. Through holes 29 are provided between the round cavities 26 and 27 and pillars 28.

Abstract: A high wattage self-ballasted fluorescent lamp includes a fluorescent tube including a pair of electrodes inside, an electronic ballast circuit portion, an outer bulb, a resin case and a lamp base. (i) The outer bulb has an outer diameter of 60 mm to 70 mm, an outer diameter of a bottom portion of 50 mm to 58 mm, and a total length of 73 mm to 85 mm. (ii) The resin case has an outer diameter of 50 mm to 58 mm. (iii) The total length of the self-ballasted fluorescent lamp is not more than 148 mm. The fluorescent tube has a distance between the electrodes of 450 mm to 540 mm and an inner diameter of 8.0 mm to 10.0 mm, and is operated at a lamp current of not more than 220 mA. Thus, the self-ballasted fluorescent lamp can be compact so that the light fixture application ratio can be improved. Moreover, the self-ballasted fluorescent lamp has a lifetime as long as 6000 hours and a lamp efficiency as high as 66 lm, and the power consumption can be reduced.

Abstract: A monochromic, multi-color and full-color cold cathode fluorescent display (CFD), comprises of some shaped white or multi-color or red, green blue color cold cathode fluorescent lamps (CCFL), reflector, base plate, temperature control means, luminance and contrast enhancement face plate, shades and its driving electronics. CFD is a large screen display device which has high luminance, high efficiency, long lifetime, high contrast and excellent color. CFD can be used for both outdoor and indoor applications even at direct sunlight, to display a character, or graphic and video image.

Abstract: A monochromic, multi-color and full-color cold cathode fluorescent display (CFD), comprises of some shaped white or multi-color or red, green blue color cold cathode fluorescent lamps (CCFL), reflector, base plate, temperature control means, luminance and contrast enhancement face plate, shades and its driving electronics. CFD is a large screen display device which has high luminance, high efficiency, long lifetime, high contrast and excellent color. CFD can be used for both outdoor and indoor applications even at direct sunlight, to display a character, or graphic and video image.

Abstract: An electrodeless high intensity discharge lamp with a lamp fill material including gallium iodide has been found to be more efficient in generating light in general, and more efficient in generating blue light. The very small size of the lamp, in combination with the high intensity in a relatively narrow blue spectral range make the lamp particularly useful in supplying blue light to a fiber optic. The relative efficiency of the lamp increases its value. In combination, the lamp provides a useful, efficient source of blue light as an input source for optical fiber, and other systems for medical and other processes using blue light as a process element.

Abstract: Lamp base contact plate for connecting a current lead-in wire of an electric lamp to a contact part of a lampholder, which contact plate being a pressed metal part of the lamp base and having a through bore for the lamp lead-in wire, is fixed firmly on an electrically insulating insert closing the end of a shell of the lamp base. The through bore for the lamp lead-in wire is formed as a first perforated bore (12) with torn skirt (20) protruding from the plane (L) of the contact plate (10) in a direction away from the insulator insert (30), and the contact plate (10), in addition to this first perforated bore (12), also includes at least two further perforated bores (14, 16, 18), each having a torn skirt (22, 24, 26) protruding from the plane (L) of the contact plate (10) in a direction opposite to the direction of the torn skirt (20) of the first perforated bore (12), towards the insulator insert (30).

Abstract: A mounting assembly for a reflector lamp. The mounting assembly comprises a 0.050" diameter stainless steel rod that has been formed into a three-turn spiral. The spiral surrounds the inner jacket mount assembly of the reflector lamp, and fits into the neck region of the reflector. The lower leg of the spiral either takes the place of, or augments a "dummy" lead presently used in the inner jacket press, so that one or both fit into the reflector eyelet opening in the neck of the reflector. The opposite end of the spiral piece extends upwardly, and is connected to the upper lead of the Model No. PAR30L inner jacket mount assembly of the Model No. MPD70 lamp.

Abstract: The invention relates to a glass composition for electric lamps which glass composition comprises SiO.sub.2, Al.sub.2 O.sub.3, Na.sub.2 O, K.sub.2 O, Li.sub.2 O, B.sub.2 O.sub.3, BaO and SrO and optionally CaO, MgO, ZnO, P.sub.2 O.sub.5, Sb.sub.2 O.sub.3, TiO.sub.2, MnO.sub.2, Fe.sub.2 O.sub.3 and/or CeO.sub.2. The composition according to the invention has a B.sub.2 O.sub.3 content of 1 to 2.8 mass %, a SrO content of 2.1 to 4.5 mass %, a BaO content of 3 to 6 mass % and of the components being present optionally, the amount of CaO is maximum 1 mass %, that of MgO is maximum 2.4 mass % and that of ZnO is maximum 3 mass %, on the condition that the total amount of SrO and B.sub.2 O.sub.3 is at least 3.6 mass %, the total amount of CaO and MgO is maximum 2.4 mass % and the total amount of MgO and ZnO is maximum 4.5 mass %.

Abstract: A monochromic, multi-color and full-color cold cathode fluorescent display (CFD), comprises of: some shaped white or multi-color or red, green, blue three primary color cold cathode fluorescent lamps (CCFL), reflector, base plate, temperature control mean, luminance and contrast enhancement face plate, shades, and its driving electronics. CFD is a large screen display device which has high luminance, high efficiency, long lifetime, high contrast and excellent color. CFD can be used for applications both of outdoor and indoor even at direct sunlight, to display character, graphic and video image.

Abstract: A fluorescent lamp unit includes a fluorescent lamp having a bulb constituting one discharge path, said bulb including three U-shaped tube portions, a lighting circuit operatively connected to the fluorescent lamp for lighting the fluorescent lamp, and a cover part having a cap at one end thereof and having a globe at other end thereof for containing the lighting circuit and the fluorescent lamp. Each of the three U-shaped tube portions has a pair of straight tube portions provided straight in a direction along to a basic center axis of the fluorescent lamp unit and has a bent portion being bent so as to be convexly curved toward the globe side opposite to the cap side thereby to form substantially U-shape and linking the glove side ends of the pair of straight tube portions. The straight tube portions are arranged equidistantly on a circumference of a certain radius from the basic center axis.

Abstract: The lamp according to the invention has a metal holder part 2 with a rece in which the pinch seal 10 of the lamp bulb 1 is clampingly fixed with the aid of a plurality of support tabs 21a, 21b, 22a, 22b, 23a, 23b. In order to reduce the danger of damage to the pinch seal 10 when the lamp is being mounted on its base, the pinch seal 10 is tapered is graduated fashion toward the base, and all the support tabs 21a, 21b, 22a, 22b, 23a, 23b that act upon the pinch seal 10 are oriented toward the broad sides of the pinch seal 10, which is substantially rectangular in cross section, while the narrow sides of the pinch seal 10 are located in the holder part 2 without touching it. The narrow sides of the pinch seal (10) are retained in the holder (2) spaced from the holder. Guide ribs (50a, 50b) are formed on the pinch seal (10) positioned off-center, and laterally relatively staggered.

Abstract: A coaxial flashlamp for optical pumping of a tunable dye laser. The flashlamp includes electrodes preferably made from a tungsten-based alloy for reduced metallic vapor deposition within the flashlamp. Positioned around the outer tube is a packed powder material having a diffuse reflectivity of the order of at least about 98%. The outer surface of the outer tube is placed under an inwardly-directed pressure provided by a pressurized cooling liquid that serves both to cool the flashlamp and simultaneously to offset internally generated pressure within the flashlamp caused by the pressure wave resulting from the movement of the ionization front through the gas within the annular gas chamber defined between the inner and outer tubes.

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: Noise is reduced in an X-ray tube by inserting a non-glass insert between sections of the glass vacuum tube. The non-glass insert has an impedance which is significantly different than the impedance of the glass tube sections. This impedance mismatch inhibits vibration energy from passing from one glass section to the other. In addition to having a different impedance than the glass sections, the non-glass insert can be made of a heavier material, thus presenting sufficient mass to dissipate vibration energy. The non-glass insert is connected to the glass sections by a pair of connecting members, each of which has a coefficient of thermal expansion closely matching that of the glass sections. Each connecting member has a ring with an annular flange extending perpendicularly therefrom. The ring of each connecting member is attached a respective one of the glass sections and each flange is attached to the insert.

Abstract: An orifice plate for a glass ribbon machine has an orifice provided with a side wall having a continuously variable angle. When used for making envelopes for incandescent lamps, the plate provides stronger bulbs.

Abstract: A shatter-resistant electric lamp includes a base; contacts for connecting the lamp to a source of electrical energy; a filament or light source electrically connected to the contacts for converting electrical energy to light; a shatterable encasement, connectable to the base, for translucently encasing the filament; and a polymer coating deposited on a first portion of the encasement so that a second portion of the encasement remains uncoated. The preferred polymer coating is poly(phenylene sulfide).

Abstract: A Christmas tree light consisting of a bulb with two leads extending from its lower end, a hollow seat, and a separation wedge. The hollow seat has an upper seat portion and a lower seat portion. A slot runs lengthwise along the lower end of the lower seat portion for receiving and frictionally engaging with the separation wedge.

Abstract: A metal vapor discharge lamp has a luminous tube constituted by a translucent ceramic tube member, end caps hermetically fixed to both ends of the translucent ceramic tube member, and electric supporting tubes hermetically inserted into respective end caps. One of the electrode supporting tubes serves also as an exhaust tube for evacuation and also as a reservoir for a metal charged in the luminous tube. The outer end extremity of this electrode supporting tube is hermetically sealed through fusion by application of heat. This hermetic seal is formed by fusing the end of the electrode supporting tube by application of heat thereto, while keeping a heat-shielding/absorbing plate held in close contact with the electrode supporting tube.

Abstract: A high intensity discharge lamp having a pair of discharge devices with one of them initially operative. The discharge devices are laterally adjacent with the higher temperature end of the operative discharge device proximate the lower temperature end of the inoperative discharge device for heating it during lamp operation. This facilitates starting of the inoperative discharge device after a momentary power interruption.

Abstract: A rough service incandescent lamp having a flexible arbor comprised of a stainless steel member that joins a glass stem press to a filament mounting structure is disclosed. The stainless member is selected to have a coefficient of expansion that both matches the coefficient of expansion of the glass stem press and of a glass cane member of the filament mounting structure. The stainless steel member allows for simplification of the fabrication process related to forming the rough service incandescent lamp while also improving the shock capability of such a lamp.

Abstract: A snap-in light bulb having a bulb through which light may be transmitted, a base connected to the bulb, and at least one arm resiliently connected to the base. The arm has a conductor element disposed for contact with a conductive light bulb socket and a plurality of spaced lobes that engage the socket threads. A system including a pole for light bulb insertion is also described.

Abstract: An arc discharge lamp resistant to surface path arcing may be formed by press sealing a dielectric barrier between the electrode roots. By properly manipulating the press seal, a barrier of the dielectric envelope material may be positioned between the electrode roots. The barrier lengthens the discharge path between the electrode roots, and thereby resists surface arc discharge. The lamp seal is then protected from surface discharge heating, and light generation properly occurs between the electrode tips.

Abstract: An improved lamp base having an eyelet with prongs and a base and apertures between the prongs and the base into which part of the glass insulator hardens to interlock the insulator with the eyelet.

Abstract: An RF laser structure (10) is disclosed which includes an elongated laser excitation cavity (27) and an electrode structure (20) for suppressing extraneous RF discharges outside of the laser cavity. The electrode structure includes an electrode (41) adjacent the elongated laser cavity (27) and extending along the laser cavity; a conductive structure (43, 45) adjacent and conductively coupled to the electrodes (41) for shielding the electrode and for providing smooth conductive surfaces; and a dielectric filler (47) encapsulating the electrode and the conductive structure, and for controlling the electric field generated by the electrode structure so that extraneous discharges are suppressed. Also disclosed is a method for making a laser electrode structure which includes the steps of forming an electrode adjacent the elongated laser cavity, and encapsulating the electrodes with a dielectric potting material.

Abstract: The disclosed process includes making a slip or slurry by mixing alumina powder, water, a deflocculant and a magnesium compound, casting the slip or slurry by drain casting and thereafter firing or sintering same. A coagulant is used as the deflocculant.A tube for a lamp, which is a unitary body of translucent alumina ceramic, has a large-diameter portion located at a central portion of the tube and two small-diameter portions located at both end portions of the tube. The tube is produced by drain casting. The tube has substantially the same wall thickness over its whole length. The inner surface of the tube is more smooth than its outer surface.

Abstract: In an incandescent lamp unit, a base assembly of a rectangular section and which holds the pinched portion of the bulb comprises a first and second bases. The first base has formed therein a first opening in which said pinched portion can be introduced and first lug members extending from the edges of the first opening and which abut the upper portion of the pinched portion to limit the latter from moving longitudinally and laterally. On the other hand, the second base is so made as to be attached to the first base and has formed therein a second opening in which the pinched portion can be introduced, and it is also provided with second lug members extending obliquely and downwardly from the second opening and which abut the lower portion of the pinched portion to limit the latter from moving in the vertical plane.

Abstract: In certain electric lamps, the lamp cap has a rectangular metal sleeve (10), which is fixed around the pinch (3) of the lamp vessel (1). The sleeve (10) also surrounds an insulator body (12), which immovably encloses a contact member (13). The contact member (13) is secured to a current supply conductor (4) of the lamp. In the lamp according to the invention, the insulator body (12) is immovably held in the sleeve (10) by depressions (16) in the corners (14) of said sleeve, which engage a respective recess in the insulator body (12).

Abstract: A vacuum chamber for containing a charged particle beam in a rapidly changing magnetic environment comprises a ceramic pipe with conducting strips oriented along the longitudinal axis of the pipe and with circumferential conducting bands oriented perpendicular to the longitudinal axis but joined with a single longitudinal electrical connection. When both strips and bands are on the outside of the ceramic pipe, insulated from each other, a high-resistance conductive layer, such as nickel can be coated on the inside of the pipe.

Abstract: A flat type cathode ray tube is disclosed which includes a flat envelope formed of a flat panel and a dish-shaped funnel, a first deflection system composed of a back electrode and a phosphor screen which are both located within the envelope in opposing relation with each other, a neck portion coupled to the envelope, the neck portion extending in the surface direction of the flat envelope having therein an electron gun, and a second deflection system formed of electro-static deflection plates which are so located within the envelope that they oppose each other across the path of the electron beam emitted from the electron gun to the first deflection system with respect to a thickness direction of the flat envelope. In this case, a projecting portion is provided from the peripheral portion of the funnel for molding material.

Abstract: A solder glass comprised of about 65 weight percent Sb.sub.2 O.sub.3 ; about 30 weight percent B.sub.2 O.sub.3 and about 5 weight percent V.sub.2 O.sub.5. The glass is black and extremely visible when employed as a molten seal in electrical devices such as tungsten-halogen lamps.

Abstract: A solder glass comprising, by weight, about 65% Sb.sub.2 O.sub.3 ; about 30% B.sub.2 O.sub.3 ; and about 5% PbO. The glass is molten at about 350.degree. C. and can be employed as a molten seal in electrical devices such as tungsten-halogen lamps.

Abstract: A solder glass comprising, by weight, about 65% Sb.sub.2 O.sub.3 ; about 30% B.sub.2 O.sub.3 ; and about 5% Bi.sub.2 O.sub.3. The glass is molten at about 350.degree. C. and can be employed as a molten seal in electrical devices such as tungsten-halogen lamps.

Abstract: An incandescent illuminating device having an antifragility coating covering at least a substantial portion of the glass envelope, the antifragility coating comprising a mixture of a relatively clear, resilient heat-stable polymer capable of adhering to glass and a plurality of light-transmitting, impact-absorbing particles, which are preferably small, hollow, heat-stable, frangible microspheres. The particles, preferably hollow microspheres, constitute from about 20% to about 60% by volume of the cured antifragility coating and are essentially colorless, have a high degree of light transmissivity, and have a low density and a diameter less than about the thickness of the antifragility coating. The particles act as a sacrificial material to absorb an impact giving the coating antifragility properties.

Abstract: The invention relates to automobile sealed-beam headlamps in which a reflector and lens assembly are hermetically sealed by an epoxy resin. A pressure relief hole in the reflector eliminates the problem of excessive expansion and contraction of the atmosphere within the lamp such as would prevent forming a hermetic seal between the reflector and lens during the epoxy resin curing cycle. A deformable metal pellet forms a hermetic seal in the pressure relief hole. An epoxy resin is applied over the deformable metal seal and cured to produce a final permanent seal.

Abstract: A seal into a fused silica envelope comprises a refractory metal wire extending through an aperture in a fused silica neck leading into the envelope. A bead of glass having a coefficient of expansion intermediate those of the refractory metal and of the fused silica is formed around and wets the wire inlead. A hermetic seal is achieved by causing fused silica from the neck to shrink around the bead and be wetted by it, forming an annular sealing zone spaced out from the wire inlead. The wire may be of tungsten in which case the electrode and inlead may be of one piece without a joint.

Abstract: A vacuum-tight assembly such as a discharge tube for a metal vapor arc lamp is formed from a transparent or translucent ceramic composition sealed with a member formed from a vanadium-zirconium alloy or vanadium utilizing a brazing alloy. The vanadium or vanadium alloy and the brazing alloy have thermal coefficients of expansion closely matching that of the ceramic composition.

Abstract: A lamp changing module for totally enclosing a lamp when the module is withdrawn from a support such as an illuminator cabinet, and permitting exposure of the lamp when properly installed and connected to the support. A potentially explosive lamp is thereby contained within the module when it is removed so that even if it explodes it will not harm nearby personnel. It also protects personnel from burn hazards associated with lamp changing.

Abstract: An electric heating element for igniting gas fuel comprises a hermetically sealed envelope made of at least 99% pure alumina and filled with a non-oxidizing gas such as hydrogen or one of the inert gases. A self-supporting coiled coil of tungsten or other refractory metal conductor dimensioned to carry a linear power loading of at least one hundred watts per inch is disposed in the envelope with coiling of the coiled coil pressing the peripheral surfaces of the coiled conductor into thermal and mechanical contact with the interior wall of the envelope. Terminals are provided for supplying current to the conductor at said power loading to heat the exterior of the envelope wall to a temperature above 900.degree. centigrade.