Abstract: An electron tube includes at least one metal film formed on a base, at least one linear member provided above the base, and at least one additional member for connecting said at least one linear member to said at least one metal film. The at least one linear member is connected to the at least one metal film by welding the at least one additional member to the at least one metal film.

Abstract: A fluorescent luminous tube includes a vacuumed envelope having two base members, an anode and a cathode installed inside the vacuumed envelope, a first and a second metal layer formed on one of the two base members, a wire shaped member mounted inside the vacuumed envelope, and a first and a second spacer, made of a metal, for supporting the wire shaped member at a predetermined height. One end portion of the wire shaped member is wound around the first spacer to be supported at the predetermined height and is interposed between the first spacer and the first metal layer to be fixed thereto. Further, the other end portion of the wire shaped member is supported at the predetermined height by the second spacer and is fixed to the second metal.

Abstract: An improved support is provided for locating a lamp filament axially within a lamp sleeve. The illustrated support is a spiral coil that includes a small diameter center portion that makes contact with the filament. On either side of the filament-contacting portion, the coil opens up to larger diameters for contacting the inner wall of the quartz sleeve within which the filament is housed. The support thus appears H-shaped when viewed from the side. A lamp filament is also provided with expansion compensation sections at either end of a central section. The filament wire in the compensation sections is wound into coils having a greater diameter and also a greater spacing between windings, as compared to coil in the central section. The expansion compensation sections are preferably capable of compressing and thereby absorbing thermal expansion of the filament during operation, without shorting the filament across adjacent windings.

Abstract: An incandescent halogen lamp used in connection with a vehicle headlamp system in which stray light attributable to reflection off of internal lamp components is reduced while the structural integrity of the lamp is maintained. The halogen lamp includes two filaments, several lead wires, and a support bridge all sealed within a glass envelope. Each filament is connected at its outermost end to a flattened end portion of a lead wire which extends along the length of the filament from near the support bridge to the upper end of the filament. The flattened outer ends of the lead wires have a narrow profile that is in alignment with the direction of illumination of light from their respective filaments. This arrangement reduces the surface area that could otherwise interfere with light emitted by the filaments, and thereby reduces the overall stray light produced by the lamp. The flattened outer ends can have a roughened surface to further help reduce the amount of light reflected off the lead wires.

Abstract: A light source composed of a planar, or substantially level, flat or curved, rigid or flexible, matrix of microfilaments integrated on a single substrate and capable of emitting light by incandescence when supplied by an electric current.

Abstract: The object of the invention is to provide an electric lamp with a coiled-coil filament, which is made more compact. An electric lamp 1 comprises a bulb 3 and a coiled-coil filament 2 accommodated in the bulb 3. According to the present invention, the coiled-coil filament 2 consists of a core filament 2′ and an additional filament 2″ which is wound around the core filament 2′ and of which the diameter is smaller than the diameter of the core filament 2′.

Abstract: A filament for generating electrons for an electron beam emitter where the filament has a cross section and a length. The cross section of the filament is varied along the length for producing a desired electron generation profile.

Abstract: The lamp of the invention has three lead rods (6, 7, 8) and two filament structure bodies (13). Each of the two filament structure bodies has three filaments (13a, 13b, 13c). All the filaments (13a, 13b, 13c) are arranged around the outside of the three lead rods (6, 7, 8). Since light from each of the filaments (13a, 13b, 13c) reaches outside of the lamp (1) without the light travel being hindered by the three rods (6, 7, 8), the light from the filaments (13a, 13b, 13c) is uniformly radiated.

Abstract: An improvement to the usable lifetime of a lamp includes the use of a primary filament, a backup filament, and a means to switch portions of the backup filament into the current flow path after a portion of the primary filament open circuits. Using bypass shunts, which do not become electrically conductive until a portion of the primary filament open circuits, an open circuited portion of the primary filament can be electrically replaced with an associated backup filament portion to keep the lamp lit. The shunts in one embodiment are made of oxidized wire and are wrapped around the primary and backup filaments, in a spaced-apart relation, forming filament pairs consisting of a primary filament segment and its associated backup filament segment. In another embodiment, support brackets are used to not only support the primary and backup filaments, but are also used to provide the bypass shunt function as well.

Abstract: A low input power consumption, compact thermal field emitter is suitable for use in electron beam systems, particularly those systems that use an array of electron beams or a miniature electron beam system. The thermal field emitter design reduces heat loss by reducing heat transfer to the base. To achieve reduced loses the design incorporates the use of high electrical resistivity, low thermal conductivity materials for construction of the filament posts and the filaments. Such materials further reduce heat loss and reduce input current requirements. In one embodiment, the base includes counterbores that reduce the heat conduction path between the filament posts and the base, and moves the contact area further from the filament.

Abstract: A light source is provided by a photonic crystal having an enhanced photonic density-of-states over a band of frequencies and wherein at least one of the dielectric materials of the photonic crystal has a complex dielectric constant, thereby producing enhanced light emission at the band of frequencies when the photonic crystal is heated. The dielectric material can be a metal, such as tungsten. The spectral properties of the light source can be easily tuned by modification of the photonic crystal structure and materials. The photonic crystal light source can be heated electrically or other heating means. The light source can further include additional photonic crystals that exhibit enhanced light emission at a different band of frequencies to provide for color mixing. The photonic crystal light source may have applications in optical telecommunications, information displays, energy conversion, sensors, and other optical applications.

Abstract: A carbon nanotube is contacted with a reactive substance which is a metal or a semiconductor. The reactive substance is heated to diffuse atoms of the reactive substance into the carbon nanotube so that the carbon nanotube is partially transformed or converted into carbide as a reaction product. Thus, a heterojunction of the reaction product and the carbon nanotube is formed. For example, the carbon nanotube (2) is contacted with a silicon substrate (1). The silicon substrate (1) is heated to cause solid-solid diffusion of Si. As a result, SiC (3) is formed as the heterojunction. At least a part of a filament material of a carbon nanotube is irradiated with electromagnetic wave to deform the filament material.

Abstract: A fluorescent lamp (10) with improved life is formed by winding a coil (30) using first, and second mandrels (45, 46), and optionally a third mandrel (70). The coil is wound around the second mandrel to provide a coil density of at least 95%. The coil is able to carry an amount of emitter material of about 0.6-1.6 mg/cm of coil. This has been found to lead to substantially increased lamp life, on both instant and rapid start circuits.

Abstract: The invention relates to a light bulb comprising a base BA to which a filament FIL is connected, which filament is intended to emit a luminous radiation and has turns arranged in spiraling fashion around an axis of revolution AX. According to the invention, the light bulb in addition comprises a plurality of hooks H1, H2, and H3, each being in contact with one of the turns of the filament, and being connected to the base BA by means of a support SUP. The invention enables to keep the filament FIL securely in position, which reduces the risk that several turns of said filament will come into contact with the support SUP, thus creating a destructive short-circuit.

Abstract: In a display device including a cathode filament containing a coiled portion and a linear portion thereof and a power feeding member, an end of the coiled portion is fixed to either a substrate made of an insulating material or an insulated support, the power feeding member being installed to contact with the linear portion of the cathode filament.

Abstract: An incandescent lamp comprising a glass bulb (3) of tubular shape in which a filament (4) is axially arranged. The end is hermetically sealed by means of a pinch (5) applied around a metal foil (1) to which an outer current lead (7) and an inner current lead (6) electrically connected to the filament are fixed. A second, intermediate flat foil (2) is connected directly to the end (9) of the filament, between the latter and the inner current lead (6), and the bulb is elbowed at the level of said second flat foil (2).

Abstract: When a number of conventional LED lamps are arranged on a wiring board and are placed in an electric bulb, it is not possible to use a printed wiring board larger than an internal diameter of a base mounting part of the electric bulb, so that a quantity of obtained light is limited. Further, light can be emitted only from a wiring printed surface, which serves as an arrangement surface of LED lamps, of the printed wiring board, so that the range of emitted light is limited. An LED chain body 2 formed by connecting a plurality of LED lamps 3 via flexible members 4 is inserted into a hollow body 1a constituting an electric bulb main body 1.

Abstract: The filament structure comprises a filament with a coiled portion and an uncoiled portion. A tube is disposed on a free end of the uncoiled portion. The tube has two ends and a passage with a central axis extending between the two ends. At least one of the ends comprises an extension which projects positively above a medium plane of the end of the tube. This medium plane is perpendicular to the central axis of the tube. A method for positioning such a tube on the free end of a filament comprises the following steps. The free end of the filament is inserted in a slit between two parallel support surfaces so that the free end is projecting upward. The tube is placed on the free end of the filament so that the extension of the tube projects downward towards the support surfaces and the lower end of the tube abuts at least one of the support surfaces.

Abstract: A lamp has a base and a light-transmitting soft-glass lamp envelope sealed to the base to form a sealed lamp cavity which is filled with a non-oxidizing gas. Current supply leads are connected to the stem feedthroughs and extend into the lamp cavity. A halogen incandescent burner is located in the lamp cavity and has a light-transmitting hard-glass burner envelope which encloses a sealed burner cavity filled with an inert gas containing halogen. The burner envelope has presses at its ends. A tungsten filament coil in the burner has extended legs at its ends that extend out of the burner cavity into the lamp cavity through the burner presses and are connected to the current supply leads in the lamp cavity to act as fuses which open upon breach of the lamp envelope, thus preventing further burner operations.

Abstract: A filament for generating electrons for an electron beam emitter where the filament has a cross section and a length. The cross section of the filament is varied along the length for producing a desired electron generation profile.

Abstract: A tungsten-rhenium filament for an operation temperature between 2900 and 3200° K is disclosed. The filament comprises an aluminum-potassium-silicon (AKS) additive. The filament has a grain microstructure comprising substantially exclusively elongated interlocking grains with a Grain Aspect Ratio (GAR) not less than 12. The rhenium content of the filament is between 0.2-0.4% by weight. A method for manufacturing a rhenium-tungsten filament is also disclosed. The method comprises the following steps. An AKS doped tungsten-rhenium alloy powder is prepared with a rhenium content of 0.2-0.4% by weight. The alloy powder is pressed and presintered, and thereafter sintered with direct current. A rhenium-tungsten filament is formed, which has a metastable crystal structure. The filament is annealed below the recrystallisation temperature, and recrystallised above the crystallization temperature. There is also provided a halogen incandescent lamp with a glass envelope enclosing a tungsten-rhenium filament.

Abstract: In a high-power dual-filament incandescent lamp for use in a reflector having an optical axis, which incandescent lamp comprises two incandescent coils which are substantially parallel to one another, which in their correct operational positions are arranged substantially parallel to the optical axis of the reflector in a lamp bulb, and which can be operated alternately, the glass bulb is arranged such that it shows a horizontal and vertical displacement relative to the optical axis of the reflector when in the correct operational position.

Abstract: The present invention provides a short arc type mercury discharge lamp that, at lamp startup time, quickly shifts glow discharge to arc discharge, and quickly shifts the arc discharge position from the coil to the electrode tip, making it possible to maintain a stable discharge state, in the short arc type mercury discharge lamp 1, a coil 5 has been arranged on the side surface of an electrode 4, and 0.15 mg/mm3 or more of mercury has been sealed inside a discharge vessel, wherein the side part 51 of the coil 5 close to the tip side of the electrode is constructed so as to be fixed to the side surface of the electrode 4, and, at least, the part 52 of the coil 5 following the side part 52 is distanced from the side surface of the electrode.

Abstract: A photonically engineered incandescence is disclosed. The emitter materials and photonic crystal structure can be chosen to modify or suppress thermal radiation above a cutoff wavelength, causing the emitter to selectively emit in the visible and near-infrared portions of the spectrum. An efficient incandescent lamp is enabled thereby. A method for fabricating a three-dimensional photonic crystal of a structural material, suitable for the incandescent emitter, is also disclosed.

Abstract: An electric bulb structure includes a housing, a base post extended into an inside of the housing from one end of the housing, a shade mounted on an opening of the housing, a first conductive wire and a second conductive wire each extended into the inside of the housing from an outside of the housing and each extended through the base post, a first filament having a first end connected to the first conductive wire, a second filament having a first end connected to the second conductive wire, and a third conductive wire having a first end connected to a second end of the first filament, and a second end connected to a second end of the second filament.

Abstract: In order to provide an incandescent lamp in which an unlit state of the lamp caused by a hang-out of the coil as well as a short lifetime thereof are prevented using a simple construction and its lifetime in practical application is long, a coil (21)-like filament (20) is held in a bulb (11) by upholding parts (30, 30′) with an axis of the coil (21) being oriented in a vertical direction, and a coil pitch of the coil (21) at the upper part thereof is made narrow as compared with that of the lower part of the filament (20). Or the filament (20) of the incandescent lamp (10) is constituted by the coil (21) of a conical shape or that of a frustum of a circular cone, and the filament is arranged within the bulb (11) in such a way that it may be held by upholding parts (30, 30′) with an axis of the coil (21) of the filament (20) being oriented in a vertical direction and the one end of the oil (21) having a smaller diameter being positioned upward.

Abstract: A tungsten-rhenium filament is disclosed. The filament has a re-crystallization temperature above 2000 ° C., and it comprises an aluminum-potassium-silicon (AKS) additive. The potassium content of the filament is between 80-110 ppm, and the rhenium content is between 0.05-0.19 % by weight. A method for manufacturing a rhenium-tungsten filament is also disclosed. The method comprises the following steps. An AKS doped tungsten-rhenium alloy powder is prepared with a rhenium content of 0.05-0.19 % by weight, and a potassium content between 80-110 ppm. The alloy powder is pressed and presintered, and thereafter sintered with direct current. A rhenium-tungsten filament is formed which has a metastable crystal structure. The filament is wound on a mandrel, and it is annealed on the mandrel below the re-crystallization temperature. The filament is finally re-crystallized above the re-crystallization temperature. A halogen incandescent lamp with an envelope enclosing a tungsten-rhenium filament is also provided.

Abstract: The object of the invention is to provide an electric lamp with a coiled-coil filament, which is made more compact. An electric lamp 1 comprises a bulb 3 and a coiled-coil filament 2 accommodated in the bulb 3. According to the present invention, the coiled-coil filament2 consists of a core filament 2′ and an additional filament 2″ which is wound around the core filament 2′ and of which the diameter is smaller than the diameter of the core filament 2′.

Abstract: An infrared lamp with a closed-off enveloping tube which encloses an emission source joined with contacts for a power supply in the form of a carbon ribbon which, extending in a direction of a long axis of the enveloping tube, determines an irradiation length of the infrared lamp in the sense of a higher irradiation output. The carbon ribbon has a length which is larger than the irradiation length by a factor of at least 1.5. With a procedure for heating a material to be processed using the infrared lamp, which makes possible short processing times in connection with a simultaneous high degree of energy efficiency, the infrared lamp may be operated such that its maximum emission lies within a wavelength range from 1.8 &mgr;m to 2.9 &mgr;m, and such that its power output comes to at least 15 Watts per cm3 of the volume enclosed by the enveloping tube over the irradiation length.

Abstract: A fluorescent lamp lighting apparatus includes a fluorescent light emitting tube; and an electronic lighting circuit for applying an electric current to the fluorescent light emitting tube. The electronic lighting circuit includes a pair of electrode filaments provided in the fluorescent light emitting tube, a pair of capacitors each connected in series to a respective one of the pair of electrode filaments and connected parallel to the fluorescent light emitting tube, and an inductor connected in series to one of the pair of electrode filaments.

Abstract: A robust coiled filament electrode for a fluorescent lamp used in high vibration environments. A cylindrical mandrel is placed within coils in each end of a coiled filament electrode. The mandrel and the coiled filament electrode are held by a mounting post. The mounting post is bent over and crimped, holding the mandrel and coiled filament electrode. The mandrel extends inward between the two mounting posts, providing support for the coiled filament electrodes. The coiled filament electrode may be made by method or process of chemically dissolving selected portions of a mandrel. Lamp life is extended, as well as the variance between lamp life is substantially reduced. The present invention is particularly applicable to applications in avionics.

Abstract: A tungsten-rhenium filament for an operation temperature between 2900 and 3200° K is disclosed. The filament comprises an aluminum-potassium-silicon (AKS) additive. The filament has a grain microstructure comprising substantially exclusively elongated interlocking grains with a Grain Aspect Ratio (GAR) not less than 12. The rhenium content of the filament is between 0,2-0,4% by weight. A method for manufacturing a rhenium-tungsten filament is also disclosed. The method comprises the following steps. An AKS doped tungsten-rhenium alloy powder is prepared with a rhenium content of 0,2-0,4% by weight. The alloy powder is pressed and presintered, and thereafter sintered with direct current. A rhenium-tungsten filament is formed, which has a metastable crystal structure. The filament is annealed below the recrystallisation temperature, and recrystallised above the recrystallisation temperature. There is also provided a halogen incandescent lamp with a glass envelope enclosing a tungsten-rhenium filament.

Abstract: A vacuum fluorescent display includes first and second substrates spaced apart from each other with a predetermined distance. Each substrate has lateral sides in horizontal and vertical directions. A plurality of anode electrodes are arranged on the second substrate in a predetermined pattern. The anode electrodes are coated with phosphors. A plurality of filaments are mounted above the anode electrodes to emit thermal electrons for exciting the phosphors. A plurality of leads are arranged on one of the opposite lateral sides of the second substrate in one of the horizontal and vertical directions to apply voltages to the anode electrodes. Supports are arranged on both of the opposite sides of the second substrate in the direction of arrangement of the leads to support the filaments.

Abstract: A method and apparatus for more precisely centering lamp leads (32, 34) uses a support mechanism (50) for radially aligning the leads. The support mechanism is a helical member having first and second helical portions (52, 54). The first helical portion has a diameter slightly less than the inner diameter of the lamp envelope to maintain a filament (30) on axis. The second helical portion has an outside diameter less than the outside diameter of the first helical portion for securing the support mechanism to a mounting mechanism (60). Here, the mounting mechanism is preferably defined by first and second flattened portions (62, 64) integrally formed on the lead that axially positions the support mechanism in place.

Abstract: The present invention relates to a Christmas bulb structure, which is provided with a pair of conducting wire in the bulb and one filament and two or more fuses connecting with the two conducting wires in parallel. It increases the well rate of the assembled light string and prevents the bulb from broken caused of the filament being burned out. And also it lengthens the used period of the bulb and the light string.

Abstract: A traffic lamp has a helical coil filament arranged in a pattern with no angles or sharp bends and with each convolution of the coil substantially tangent to the focal plane of the lamp. The filament may be generally in the pattern of the lower case Greek letter Omega and is supported on seven support wires, so that the same filament length can be used for both 120-volt and 240-volt applications. In one embodiment, the lamp has two filaments arranged as arcs of a common circle lying substantially in the focal plane, each arc being supported on three support wires, the filaments being respectively connected in series with diodes so that the filaments respectively conduct on alternate half cycles of the AC source voltage.

Abstract: A cathode ray tube include phosphor screen and an electron gun. The electron gun includes an indirectly heated cathode structure and plural grid electrodes arranged in axially spaced relationship. The cathode structure includes a base metal having an electron emissive material coating and a heater for heating the base metal. The heater includes a major heating portion having a spirally wound heating wire and a pair of leg portions connected to opposite ends of the major heating portion. The major heating portion and an inner portion of each of the leg portions on a major-heating-portion side thereof are covered with an insulating coating, and the heater is welded to electrical conductors for applying a voltage thereto at an outer portion of each of the leg portions, the outer portion not being covered with the insulating coating.

Abstract: A filament comprises a generally thin metal component, such as a sheet, ribbon, or foil. The filament comprises at least one emitter, at least one current-condensing structure and a tab on each end of the at least one emitter. Each tab is connectable to a support system, comprising for example a lead and attachment post. When a current is passed through the filament, the current-condensing structure establishes current flow through the filament resulting in a desired temperature distribution across the emitter, for example a substantially uniform temperature distribution. A predictive tool for determining a geometry of a filament to provide a desired temperature distribution is set forth. The filament may be curved, and methods and systems for providing a curved filament are also provided. Attachment systems are further disclosed for attaching an emitter to a support structure.

Abstract: A cathode ray tube includes a phosphor screen and an electron gun. The electron gun includes an indirectly heated cathode structure and plural grid electrodes in axially spaced relationship. The cathode structure includes a cap-shaped base metal having an electron emissive material coating and a heater for heating the cap-shaped base metal. The heater includes a major heating portion having a spirally wound heating wire and leg portions, and each of the leg portions includes a first multilayer winding portion having heating wires wound spirally in plural layers and a second multilayer winding portion intermediate between the major heating portion and the first multilayer winding portion and having heating wires wound in plural layers.

Abstract: The invention relates to the fastening of incandescent coil filaments to current lead-in wires in electric lamps. One end (41) of the current lead-in wires is flattened and U-shaped. The U-shaped segment (41) of the current lead-in wire forms a gap-like seat (45) for a coiled incandescent coil-filament end (3a), the gap width of which is smaller than the outside diameter of the incandescent coil-filament end (3a).

Abstract: An airway obstruction luminaire has a luminaire base; a substantially cylindrical Fresnel lens having a lens axis; a halogen lamp having a lamp base, and a substantially linear filament; and a lamp bracket which positions the lamp such that a filament axis of the filament is coincident with the lens axis. The filament is energized by a power supply connected to a first filament end and second filament end, which are separated by an effective length l.sub.E of less than 1 inch. The filament is preferably formed as a helical coil. The lamp is designed to operate at a lamp rated voltage V.sub.L between about 12 and 30 volts. The power supply voltage V.sub.P is reduced if V.sub.P is greater than V.sub.L. The second filament end is supported by a second end support structure configured to reduce shadowing. The lens is preferably an acrylic plastic lens fabricated by injection molding.

Abstract: The electric incandescent lamp has a tubular quartz glass lamp vessel (1) in which a filament (10) having adjoining turns is axially disposed. The filament (10) is kept centered in the lamp vessel (1) by supports (15) which are connected to the filament (10) intermediate its ends (12) and which bear against the lamp vessel (1). The turns (11) of the filament (10) are formed as polygons, and the adjacent angles of adjoining turns are angularly displaced relative to one another about the axis (2) of the lamp vessel (1).

Abstract: An electric discharge wire-holding structure for a wet-type electric dust collector is disclosed. The holding structure is capable of increasing the service life of electric discharge wires by preventing the presence of a minute clearance at the end of the electric discharge wire which is fastened on the electrode bar, thereby providing a continuous path for a flowing current and preventing electric wear due to a potential difference. The holding structure includes a hook provided at the fastened end of an electric discharge wire, and which is fastened on a planar set seat formed on an electrode bar by a set screw.

Abstract: An infrared thermal lamp, which has a filament mounted to the lower end of a support rod downwardly extending from a stem of a base, is disclosed. The infrared thermal lamp includes an insulating plate having an anchoring slot at the center for receiving the lower end of the support rod in a semi-melted state. Thus, the insulating plate is fixedly mounted to the support rod, and the anchoring slot is opened at the top end and is closed at the bottom end and has an enlarged diameter at the bottom end, thereby improving productivity, saving labor, automating the mounting process of the insulating plate, and reducing production cost.

Abstract: An automotive lamp bulb is provided that is easy to assemble. A glass bulb has a tip with a short projection at its upper end. A common lead wire is secured in a neck portion of the glass bulb with the aid of a bead. The bead makes it possible to shorten the upper end of the glass bulb. The use of the bead also makes it easier to align the common lead wire with the neck portion. Because the bead is interposed therebetween, the common lead wire is allowed to slide in relation to the glass bulb, thus making it possible to use inexpensive hard glass. Consequently, an inexpensive and compact automotive lamp bulb can be easily manufactured.

Abstract: A magnetron includes a cylindrically shaped cathode having an electron emitting surface and a filamentary heater adapted to raise the temperature of the emitting surface sufficient to permit thermionic electron emission therefrom. The filamentary heater comprises a first filament support member having an axial shaft coaxially disposed within the support sleeve and is coupled at an end thereof to a portion of the support sleeve. The first filament support member has a plurality of first tines extending from an opposite end of the axial shaft. A second filament support member has an axial shaft coaxially disposed within the support sleeve along a common axis with the axial shaft of the first filament support member. The second filament support member has a plurality of second tines extending from an end of the axial shaft in substantial alignment with the first tines.

Abstract: Disclosed are a process for fixing a filament onto a support in an incandescent lamp in which the filament is prevented from being deformed when it is welded onto a support and also a filament supporting structure to be established by the process. The filament fixing process comprises wrapping a foil body around each supporting end portion of a filament; squeezing the wrapped foil body together at positions close to each end thereof to form a cylindrical portion and a fin-like portion protruding from the cylindrical portion; and welding the cylindrical portion onto a support (e.g. a support wire or a supporting piece of a shade) for the filament such that the fin-like portion of the foil body may be situated within the distance or range corresponding to the diameter of the cylindrical portion as measured from the surface of the support.

Abstract: A lamp which provides substantially uniform illumination over a predetermined area which includes a glass envelope having a lensed end and a curved filament contained within the envelope. The filament contains a plurality of coils which are disposed in a concave orientation with respect to the lensed end.

Abstract: The invention concerns an electrical incandescent lamp with a mount for hing a filament coil (4), whereby the coil is suspended by at least one hook-shaped holder (7) provided with a free end, in which filament coil (4) is suspended. Free end (7a) of hook-shaped holder (7) is bent in such a way that it (7a) constricts the suspension opening of hook-shaped holder (7). In this way, an unhooking of the coil is avoided when vibrations occur.

Abstract: A cathode structure comprises at an end portion (1) an electron-emitting material (4) and a heating element (5) of wire (7), said cathode structure having a plurality of primary helical turns (8). These primary turns are used to form a first series of secondary turns (9) which are wound in a first direction with a pitch and which extend towards the end portion (1), and to form a second series of secondary turns (10) which extend from the end portion (1) and which have the opposite direction of winding yet the same pitch. Near the end portion (1), the first and second series of turns (9, 10) are interconnected by an arc-shaped connecting portion (12) having primary turns (8). This arc-shaped connecting portion (12) has a span S.sub.a and a rise r.sub.a, the ratio r.sub.a /S.sub.a preferably ranging from 0.3 to 0.5.