Abstract: An inductively coupled fluorescent discharge lamp includes a light transmissive envelope having a re-entrant cavity that has an outer surface inside the envelope, and an excitation coil inside the re-entrant cavity, and a spring clip that is attached to the outer surface of the re-entrant cavity by spring action of the spring clip on the outer surface, where the spring clip includes an amalgam. The spring clip may include a layer of the amalgam plated on a surface of the clip, or an amalgam-bearing flag attached to the clip.

Abstract: An arc tube includes: a tube spherical portion containing a pair of electrodes each of which has a shaft portion and a coil winding portion formed by winding coil around the shaft portion; and a pair of seal portions extending from both sides of the tube spherical portion. The coil winding portion of at least one of the electrodes has a coil portion formed by winding the coil at least once around the shaft portion in the longitudinal direction of the shaft portion, a tip disposed on the tip side of the coil portion, and a base disposed on the base side of the coil portion. The coil of the base positioned on the surface side of the electrode is melt-treated. The coil forming the base is not melted to be combined with the shaft portion.

Abstract: An electrodeless self-ballasted fluorescent lamp includes: a luminous bulb 1 having a cavity portion 15; an induction coil 3 inserted in the cavity portion 15; a ballast 4 electrically connected to the induction coil 3; and a base 7, wherein the luminous bulb 1, the ballast 4 and the base 7 are configured as one unit. The luminous bulb 1 includes an approximately spherical outer tube 12 and an inner tube 11. At least the surface of the upper hemisphere of the outer tube 12 is coated with a silicone rubber 10 having the property of transmitting light.

Abstract: A short-arc ultra-high pressure mercury lamp in which the change in the shape of the electrodes can be suppressed and a stable arc discharge can always be produced is achieved in an arrangement in which, in the silica glass arc tube, there is a pair of opposed electrodes with a distance between them of at most 2 mm and the tube is filled with at least 0.15 mg/mm3 of mercury, a rare gas, and a halogen in the range from 1×10?6 ?mole/mm3 to 1×10?2 ?mole/mm3, by at least one of the electrodes having a melt part formed toward the electrode tip by winding the electrode rod with a coil and by melting the part of the coil oriented towards the electrode tip at least in the area of its surface. A part of the coil located away from the electrode tip is unmelted and the base point side area of the coil facing away from the electrode tip is rounded and does not have sharp edges.

Abstract: A coiled filament has a light emitter with a reduced volume as best possible to serve in downsizing a light bulb and elevate an illumination with high efficiency in an illuminated field. A flat coiled filament wound into flatness is arranged in the form of a helix or ring, locating the longer axis of the flatness in parallel with the central axis of the coiled filament or to cross the central axis at an appropriate angle. Alternatively, it is arranged in coincident with the radial axis of the coiled filament or at an appropriate angle. Alternatively, the flat coiled filament is U-shaped and a pair of such U-shaped flat coiled filaments are mated with each other through their open ends, while the inner surfaces of their closed ends are kept in non-contact with each other. Alternatively, the flat coiled filament is formed circular.

Abstract: A low-pressure mercury vapor discharge lamp (1) comprising a discharge vessel (2) having two end portions (3), wherein an electrode carrier (9) is arranged in an end portion (3) and carries an electrode (10) for generating and maintaining a discharge in said discharge vessel (2), wherein said electrode carrier (9) is at least partly made of a bimetal or a memory metal, and wherein said electrode carrier (9) is formed such that the distance between said electrode (10) and the far end of said end portion (3) increases if the temperature of said electrode carrier (9) increases.

Abstract: An electrodeless fluorescent lamp employs a glass envelope made from a single linear tube or bulb and a reentry cavity disposed on the envelope axis and sealed to the envelope. The envelope is filled with inert gas and mercury vapor. Phosphor and protective coatings are disposed on the inner surfaces of the envelope and the cavity. An induction coil of A few turns made from silver coated copper wire is wrapped around the envelope in its axial direction. The inductively-coupled axially uniform plasma is generated inside the envelope. The discharge electric field and current form a closed-loop path inside the envelope along its walls. The introduction of the reentry cavity decreases the lamp wall loading without loosing lamp power efficiency and efficacy. The lamp is operated at frequencies from 50 kHz to 200 MHz and RF power from 5 W to 2000 W without the use of ferrite inside of the reentry cavity.

Abstract: A high pressure discharge lamp has a pair of electrodes in a discharge tube. Each electrode includes a coil and an electrode rod with a tip, the coil being set around the electrode rod near the tip. The tip of the electrode rod and an adjacent portion of the coil are fused together during the initial discharge. To be more specific, the coil covers the electrode rod near the tip, with the tip of the electrode rod being left uncovered and a length of the tip being &Dgr;L that satisfies an inequality 1/50*R3≦&Dgr;L≦1/5*R3 where R3 is an outer diameter of the coil adjacent to the tip. Alternatively, the electrode can be first formed before being set in the discharge tube, by integrally melting the tip of the electrode rod and the adjacent portion of the coil using, for example, a plasma or laser.

Abstract: A high pressure discharge lamp in which the total length of the discharge tube can be shortened without changing the discharge length of the electrodes by the ends of a fused silica glass discharge tube having hermetically sealed portions being bent essentially at right angles relative to a discharge part of the discharge tube so that it has an essentially overall angled shape and by there being electrodes with bent end parts within the discharge tube, the electrodes further having base points that are wound with coils of emissive material, and with these coils projecting partially into the discharge space with the remaining parts of the coils being located within the hermetically sealed portions.

Abstract: An electrode for electrical lamps comprises a core pin with a pushed-on helical member. A boss (9) projecting beyond the diameter of the core pin (7) is laterally constructed on the core pin at a spacing from the tip, the helical member (8) being arranged with at least one turn behind the boss.

Abstract: The electric incandescent lamp has a lamp vessel (1) in which a filament (3) is disposed substantially concentric with the longitudinal axis (2) of the lamp vessel (1). Current conductors (4) extend from the lamp vessel (1), an internal conductor (10) part of which is substantially concentrically with the axis (2) and has an end portion (11) having unround cross-sections (12). An end portion (6) of the filament (3) is wound onto the unround cross-sections (12) of a respective internal conductor (10) to constitute clamping windings (5). The lamp is of a simple construction to obtain reliably a concentrically mounted filament.

Abstract: A high performance miniature projection lamp which includes a glass envelope having a pair of opposite neck portions each with a coaxial central opening having a reduced section and an hermetically sealed central chamber having a volume of about 130 mm.sup.3 which contains a fill. The fill includes an argon pressure at room temperature at a range of about 0.5 atmospheres to about 2.0 atmospheres and mercury in an amount in the range of about 5 mg to about 15 mg, and a mixture of metal halide material in an amount from about 50 up to 1000 micrograms. A pair of axially aligned electrodes are positioned at opposite neck portions and separated form each other by a predetermined distance. The electrodes each have a shank portion which each having a coil wrapped around its end.

Abstract: An incandescent halogen lamp is operated under convection-free conditions. In this way, light yields of about 15 to 20 lm/W with service lives of about 2000 hours can be attained. The important parameters are the bulb dimensions, luminous element dimensions, and fill gas properties.

Abstract: The high pressure discharge lamp has electrodes which each have a wrapping of tungsten wire near the tip of the electrode rod. The electrode rod has unround cross-sections, formed by indentations and bulges. The tungsten wire, wrapped around the electrode rod, is in substantially circumferential contact with the unround cross-sections, thereby keeping the wire fixed to the rod.

Abstract: The high pressure discharge lamp has refractory electrodes each having a top and a winding of refractory metal wire, which has turns and is, in an area thereof remote from the top, secured to the electrode. The turns of the winding are made to have torsion. Thereby an accurately defined position with respect to the top of the electrode is obtained. The direction of the torsion is opposite to the direction of the turns, which causes neighbouring turns to press one against the other.

Abstract: To reduce flicker in low-power, high-pressure discharge lamps, the electrs, in the region in which they face each other, have wrap windings, of about 2 to 4 turns wrapped thereabout and the terminal end of the electrode has an essentially spherical end head element (19, 19', 39) melted thereon, which essentially spherical head element may be a segment of a sphere, ellipsoid-shaped or similarly formed. The electrode shaft, the wrap winding and the sphere preferably are all made of undoped tungsten, although the electrode shaft may be of a lower melting metal, such as rhenium.

Abstract: A cathode for a discharge lamp includes a longitudinally extending central core of a high temperature, electrically conductive metal; and a coil of high temperature, electrically conductive metal wound thereabout, said coil being fastened to said core at least in part by mechanical interference. The mechanical interference can be achieved by keyways formed in the core surface. During winding, at least some of the turns of the coil enter the keyways providing a good, mechanical engagement of the coil with the core. The keyways can be formed by heating the core and compressing or forging areas with tools or the keyways can be formed by grinding or by any other suitable means.

Abstract: A discharge tube having a pair of opposite electrode assemblies disposed in a discharge space defined by a peripheral wall and charged with gas, and an a.c. source connected at one end to one of the pair of electrode assemblies and at the other end to the other of the electrode assemblies, each of said opposite electrode assemblies comprising a sintered metallic electrode for emitting electrons and a filament electrode disposed closely adjacent to the sintered metallic electrode, for emitting thermoelectrons, and the sintered metallic electrode and the filament electrode being electrically connected in parallel by means of the associated lead wires.

Abstract: In a mercury vapor arc discharge tube having a pair of electrodes, an emissive material disposed on the electrodes consists essentially of a single phase compound of Ba.sub.x Sr.sub.1-x Y.sub.2 O.sub.4 where x is from about 0.25 to about 0.95.

Abstract: A discharge tube includes a pair of electrode devices mounted within a discharge tube body in an opposed relation to each other, each of the pair of electrode devices including an arc discharge electrode and a glow discharge electrode. An electron-radiating substance vaporized and emitted in a scattered manner from the arc discharge electrode is captured by the glow discharge electrode. The arc discharge electrode is composed of a sintered body containing the electron-radiating substance therein.

Abstract: A single-sealed metal-vapor discharge lamp forms a press sealed portion on one end to seal in a discharge space starting noble gas, light emission metal, and mercury. The discharge lamp has a pair of electrodes with bent portions whose tip ends are bent opposite to each other in the discharge space; a pair of inner metallic foil conductors, to each one end of which the proximal ends of the electrodes are joined; and an arc tube enclosing a pair of internal lead wires, each one end of which is joined to the other end of the inner metallic foil conductors. The electrodes which are arranged approximately parallel in the arc tube. A bend angle .theta. of the bent portions arc is 60.degree..ltoreq..theta..ltoreq.120.degree., and the curvature radius R of the periphery of the bent portions is approximately R.gtoreq.1.2d (where, d is wire diameter of the electrode rod).

Abstract: An emissive material for use in a vapor discharge device including reacted Ba.sub.x Sr.sub.1-x Y.sub.2 O.sub.4 wherein X satisfies the following: 1>X.gtoreq.0. A vapor discharge device is provided having an arc tube which includes electrodes therein coated with such emissive material.

Abstract: A single side-sealed metal vapor discharge lamp is disclosed which includes a discharge tube having a sealed section at one end and a discharge region defining envelope at the other end, a pair of metal foils sealed at the sealed section and a pair of electrodes, the discharge region of the discharge tube containing a rare gas for starting and a filled gas containing mercury and light emitting metal. The electrodes are each comprised of a rod connected to the metal foil and a coil of at least one turn mounted on the forward end portion of a bent end portion of the rod, the coils being oppositely spaced apart by a predetermined distance in the discharge region. The coil is formed of a higher melting point material than a surface material of the forward end portion of the bent portion of the rod. With the length from the bent portion to the forward end of the rod indicated by L1, the length of the coil by L2 and the wire diameter of the coil by d, the following inequalities are satisfied: L1.ltoreq.3d and d/2.

Abstract: The high-pressure gas discharge lamp according to the invention has electrodes which comprise an electrode rod 24 and a helical winding 26 near its tip 25 projecting into the lamp vessel, both of mainly tungsten. The winding 26 has a first layer of turns 27 helically wound around the rod 24 and locally having a turn of high pitch 29. The winding 26 has around the first layer 27 an outer layer of turns 28, at least two of the outer layer turns interlock with the turn of the high pitch 29 of the first layer 27 at contact areas 30. The turns engage with clamping fit the rod 24 diametrically opposite thereto. As a result, the winding 26 is fixed on the rod 24. If the first layer 27 is integral with the outer layer 28, the winding 26 can be sufficiently fixed with one turn of outer layer 28 interlocking with the high pitched turn 29.

Abstract: The high-pressure discharge lamp has electrodes which comprise a tungsten rod (24) which projects inside the lamp vessel and around whose end (25) projecting inside the lamp vessel a tungsten wire portion (26) is helically wound. The ends (30, 31) of the helically wound wire portion (26) are located within the sheath (29) of this wire portion (26) and the end faces (32, 33) are rupture surfaces devoid of burrs.

Abstract: The high-pressure gas discharge lamp according to the invention has electrodes comprising a rod of mainly tungsten and a helical winding of mainly tungsten near the tip of the rod. The winding has a first layer of turns, which is integral with a second layer of turns. The turns of the second layer are wound with torsion in the wire and surround turns of the first layer which are also wound with torsion. The direction of the torsion in a turn is equal to the direction in which the turn extends around the rod. As a result, the turns with torsion surround with tight fit their substrate and the winding is securely fixed ot the electrode rod.

Abstract: An electrode having a self-supporting cylindrical open coil of tungsten or molybdenum wire having a lead wire of tungsten or molybdenum passed coaxially through the coil and connected thereto. The turns of the coil engage each other. The central lead wire has a smaller diameter than the coil wire, this thin portion extending to a location just before the outermost turn of the coil.

Abstract: The high-pressure gas discharge lamp according to the invention has at least one electrode comprising an electrode rod and a helical winding near its tip projecting into the lamp vessel, both mainly of tungsten. The winding has a first layer of turns directly around the rod with locally a turn of high pitch P. The winding has around the first layer another layer of turns which is wound in opposite direction and has a turn of high pitch gripping around the turn of high pitch of the first layer forming therewith contact areas located diametrically opposite to each other. Between the contact areas high pitched turn of the outer layer engages the rod with a clamping fit. An additional turn of the second layer wound in the same direction as the first layer is disposed over the high pitched turns of the second layer in the region where the high pitched turn of the second layer engages the electrode rod. The winding has the same diameter over its entire length and is fixed firmly to the electrode rod.

Abstract: A high-pressure metal vapor arc lamp, lit by direct current power supply, which includes an arc tube in which an anode and a cathode are arranged opposite to one another. The cathode includes a cathode shaft and a coil element wound around the cathode shaft. A diameter of a wire of the coil element is fixed within specific values in connection with a diameter of the cathode shaft, a pitch of the coil is fixed in connection with a diameter of the wire of the coil and I.sub.L (discharge current)/d.sub.0.sup.2 (external diameter of the coil) is determined within specific values, whereby an arc spot can be easily moved to the top portion of the cathode even if the arc spot is generated at the base portion of the cathode.

Abstract: Sintering aids are disclosed which improve the sintering of emission materials in high pressure discharge lamps. The sintering aid is Nb.sub.2 O.sub.5 or Ta.sub.2 O.sub.5 or a mixture thereof along with an alkaline earth oxide with is mixed in the amount of 2 to 15 weight percent sintering aid with 98 to 85 weight percent electron emissive material.

Abstract: A high-pressure sodium vapor discharge lamp contains an electron-emitting material consisting of alkaline earth metals bound to oxygen and tungsten bound to oxygen. It has been found that such lamps of less than 400 W which have either a high Hg/Na ratio or use neon/argon as a starter gas fail prematurely when the alkaline earth metals and tungsten in the electron-emitting material are present in stoichiometric quantities.The free ends of electrodes of lamps according to the invention are wound with tungsten wire. Electron-emitting material comprising carium, strontium and calcium bound to oxygen and tungsten bound to oxygen is disposed in the cavities formed between the tungsten wire turns. The molar ration of the total barium, strontium and calcium bound to oxygen to the tungsten bound to oxygen is between 8 and 50.

Abstract: A high pressure discharge lamp comprising a discharge vessel in which an electrode comprising a resistive element is present, said resistive element consisting of two parallel arranged branches having substantially the same electrical resistance. With such an electrode construction it is achieved that the starting point of the discharge on the electrode is stabilized.