Abstract: To increase heat dissipation from a plasma display panel, a heat sinking unit 2 bonded to a curved back surface 11 of a panel unit includes a large number of fin blocks 21 arranged spaced apart from each other by a prescribed distance and a flexible thin-wall portion 22, and a joining section 221, which consists of fin anchoring portions 212 and thin-wall portions 22, is capable of being bent between the fin blocks 21, thus allowing the heat sinking unit 2 to conform to the curvature of the panel unit back surface 11. When using a heat sinking unit not structured to conform to the curvature of the panel unit back surface 11, a high-orientation graphite film as a heat equalizing layer is interposed between the panel unit back surface and the heat sinking unit.

Abstract: A sulfur, selenium, and/or tellurium based lamp for providing visible light. The lamp is operated in a regime for providing high efficacy wherein the ratio of the volume to surface area of the bulb is greater than 0.45 cm, the concentration of the sulfur, selenium, or tellurium is less than 1.75 mg/cc, and the power density is between about 100 watts/cc and 5 watts/cc.

Abstract: A lighting unit includes a discharge vessel having a wall provided with a first luminescent layer, a gas fill consisting essentially of neon at a pressure less than 30 mbar, and a means for providing a constant DC current for exciting the fill in the discharge vessel to emit UV light for exciting the luminescent layer. DC operation offers substantially higher luminous flux over AC operation. The lighting unit may further include a housing having a reflective surface, a second luminescent layer, and a filter incorporated within the discharge vessel.

Abstract: A liquid crystal display is provided using a flat panel of microlamps being formed from gas discharge display structures and made by the method of making the same utilizing integrated circuit fabrication techniques. The flat panel of microlamps is formed into an array for providing light to individual pixels, or a small number of pixels, in a liquid crystal display. Such microlamp lighting can increase the illumination of LCDs.

Abstract: A light source device in which the radiated light from the dielectric barrier discharge lamp can always be stabilized even if the discharge vessel of the dielectric barrier discharge lamp is large or the load on the tube wall within the discharge vessel is small. This is achieved according to the invention by the provision of a light source device having a discharge lamp which has a generally cylindrical, coaxial double-tube arrangement of an outer tube and an inner tube, in which there is an outer electrode on the outer tube, in which there is an inner electrode on the inner tube, and in which a discharge space between the inner and outer tubes is filled with a discharge gas for formation of excimer molecules by a dielectric barrier discharge, and of a power source for operating this discharge lamp in accordance with the relationship: Vs/Vp.ltoreq.0.5 where Vs is the starting voltage and Vp is the voltage applied to the discharge lamp during steady-state luminous operation.

Abstract: The electric discharge lamp has a discharge vessel (2), which is mounted in an outer bulb (1). A glass sleeve (10) is surrounding the discharge vessel. A coiled wire (11) is used as an envelope (11) to a glass sleeve. The wire is in an electrically floating manner fixed around the sleeve (10), e.g. by clamping fit. The construction of the lamp is simple an effective to protect the outer bulb (1) from being damaged by an explosion of the lamp vessel (2) and to prevent sodium, if present, to disappear from the discharge vessel as a result of photoemission.

Abstract: A sodium containing lamp constructed to include of a fused quartz or fused silica arc chamber wherein the fused quartz and/or fused silica contains less than about 0.05 parts per million sodium. The arc chamber of the invention demonstrates a resistance to sodium diffusion resulting in a longer lived lamp with excellent color maintenance.

Abstract: The invention relates to a high-pressure discharge lamp with an outer bulb urrounding the discharge vessel, and to a process for producing a high-pressure discharge lamp. The outer bulb (1) comprises a glass that has a low viscosity and in particular a lower softening temperature than the quartz glass of the discharge vessel (2), and is melted directly onto the ends (5a, 5b) of the discharge vessel (2), which is sealed on both ends. As the glass for the outer bulb, a quartz glass doped with viscosity-lowering additives, in particular alkaline-earth metal borates, is used, while the discharge vessel comprises undoped quartz glass. In addition, the quartz glass of the outer bulb is preferably doped with rare earth metal additives that absorb UV radiation.

Abstract: A metal halide arc discharge lamp rated for not more than 150 watts and 100 volts and which can be operated in either a horizontal or vertical position without a significant change in color temperature or lumen output has an ellipsoidal arc chamber mounted within a nitrogen-containing outer envelope. The arc chamber contains a pair of electrodes, mercury and sodium and scandium iodides and is coated at each end with a heat reflective coating. The chamber aspect ratio, electrode insertion length, metal halide density, coating length and wall loading are defined within narrow ranges.

Abstract: An electrodeless, low pressure gas discharge lamp includes a vitreous envelope containing a discharge medium and being shaped with an external chamber for receiving an electrical excitation circuit. The excitation circuit is effective for exciting the discharge medium to emit light with electromagnetic fields that are generated by the excitation circuit. A circuit is included for supplying electrical power from power mains to the excitation circuit. A transparent, electrically conductive coating is provided atop the vitreous envelope and is electrically connected substantially directly to one of the power mains at any given time. A transparent, electrically insulative coating is disposed atop the electrically conductive coating, and comprises a contiguous, inorganic glass layer. The insulative coating preferably has a minimum coating thickness of at least about 3.1 microns.

Abstract: An optically transparent polycrystalline alumina sintered body consists essentially of alumina, magnesia, yttria and zirconia. The magnesia is present in an amount of about 0.020 wgt. percent, the yttria is present in an amount of about 0.035 wgt. percent, and the zirconia is present in an amount of about 0.018 wgt. percent. An arc tube for a high pressure sodium lamp made from this composition has greatly increased resistance to sodium loss and concomitant outer jacket darkening, whereby the effective amount of lumen output is increased.

Abstract: A compact fluorescent lamp is provided in a coiled or helical configuration in order to maximize the length of discharge tubing for a given height. A non-uniform coating of phosphor is provided on the interior surface of the discharge envelope to inhibit light otherwise directed inwardly into the lamp toward a longitudinal axis of the helical configuration and redirect the light outwardly through an outer circumferential portion having a thinner phosphor coating. This results in increased light output for an given lamp geometry and lamp power.

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: A low breakdown voltage gas discharge device includes an envelope filled with an appropriately selected working substance. Two main electrodes are sealed in a vacuum-tight manner inside the envelope, and are separated by a predetermined distance. A supplemental electrode extends between the main electrodes along the direction of the electrical discharge, and has its geometrical and electrical parameters satisfy the following equation:S=I.sub.d /C,where S is the surface area of the supplemental electrode and depends on the distance between the main electrodes, I.sub.d is the current flowing in the supplemental electrode during normal glow discharge, and C is a constant characterizing the current I.sub.d, the composition of the supplemental electrode, and the type and pressure of the working substance. The supplemental electrode is connected to an AC or DC power source via a switch, so that the supplemental electrode always acts as a preparatory glow discharge cathode.

Abstract: An emission device which operates a cadmium lamp with a light intensity sufficient for used in industrial applications is achieved by an emission device having a cadmium lamp with a fluorescent tube within which a cathode and an anode are space a small distance apart and a buffer gas for easier initiation of luminous operation and metallic cadmium in an amount per unit volume of the fluorescent tube of 1.times.10.sup.-4 g/cm.sup.3 to 3.times.10.sup.-3 g/cm.sup.3 are encapsulated, and a power source device for supplying an electrical input between the cathode and the anode in an electrical input range from 0.5 kW to 5.0 kW with the condition:6.03+2.79 W.ltoreq.r.ltoreq.40being satisfied, where the electrical input of the power source device into the cadmium lamp in steady-state luminous operation is W (kW) and the maximum inside radius of the fluorescent tube is r (mm).

Abstract: A lighting and/or indicating apparatus for a motor vehicle, of the type comprising an external light transmitting element and a base arranged behind the latter, typically consists of a lighting and indicating cluster. The light transmitting element comprises an outer panel, the base comprises an inner wall, and the two walls together constitute a thin gas-tight envelope and define at least one closed cavity. This cavity, or each cavity, contains two electrodes and a suitable gas under low pressure, the apparatus having means for applying voltage for starting and maintaining a luminescent gas discharge in the cavity, so that the envelope itself constitutes at least one light of the gas discharge type. The appearance and light output are improved, and the light beams emitted are highly homogeneous.

Abstract: A low pressure gas discharge lamp has a low profile which includes at least one glass plate with a tube envelope channel having a cover plate covering the evacuation tube which is substantially flush with the plate.

Abstract: A microlamp structure and method of making the same is set forth having light collection and light directing features. The microlamp structure is of a luminescent gas discharge type. The light collection structures may include types of reflectors while the light directing structures may include lens features. These features may be included singly or in combination and may be provided on the exterior of the microlamp structure or on the interior of the microlamp at a light forming cavity.

Abstract: A metal halide arc discharge lamp comprising: an arc tube containing an arc generating and sustaining medium and having first and second electrodes sealed at opposite ends thereof; an outer envelope surrounding said arc tube and having first and second terminals for electrical connection thereto; an electrical connector coupling said first electrode to said first terminal; an electrical connector coupling said second electrode to said second terminal; a heat reflecting coating on at least one end of said arc tube; a starting aid operatively associated with said arc tube; and a light transmissive shroud positioned about said arc tube on at least two sides thereof; said arc tube having a given wall thickness of about 0.5 mm and said shroud having a thickness greater than said given thickness, the ratio of said shroud wall thickness to said arc tube wall thickness being about 2.

Abstract: A hydrogen discharge lamp has a glass lamp enclosure formed with a radiation-emitting window and receiving a body of a zirconium-cobalt alloy forming in part a hydride which constitutes a reservoir for hydrogen or deuterium and enabling controlled liberation of the hydrogen or deuterium from the reservoir. The zirconium-cobalt alloy simultaneously forms a getter for elements interfering with spectral purity of a hydrogen discharge emission from the lamp. An electrical discharge is effected in the hydrogen or deuterium liberated in the enclosure to cause the emission of light through the window.

Abstract: A metal halide lamp includes a luminous tube which is sealed and filled with predetermined rare gases and metal halide, a pair of electrodes provided in the inner portion near both ends of the luminous tube, an outer tube which encloses the luminous tube, and a pair of socket connectors electrically connected with the electrodes, wherein the luminous tube cross-section forms an uneven pattern and is pleated along outer and inner surfaces of the luminous tube. The atmospheric pressure in the luminous tube is stabilized to prevent the bending of the arc. Accordingly, the lifetime of the luminous tube is prolonged and high vapor density is obtained, thereby improving luminous efficiency and color rendering by far.

Abstract: A high pressure discharge lamp having an arc tube for operation in a generally horizontal position. The arc tube has a generally cylindrical body with end chambers of continuously reducing cross-section in which respective discharge electrodes are arranged. Press seals sealing the end of the arc tube in a gas tight-manner are offset from the axis of the cylindrical body in a direction normal to the press seals and away from the tip-off. The lower circumferential portion of the cylindrical body is smoothly curving and free of flats and the lower portions of the end chambers are smoothly curving and free of crevices.

Abstract: A nearly pure neon is described along with a method of operating the lamp. A phosphor is coated on the lamp wall. By properly stimulating the neon, ultraviolet light may be emitted, that can stimulate the phosphor to a first light emission. The lamp may then be operated to produce a visible light emission that is the result of neon emission or of intermediate combinations of the neon and phosphor emissions. A single neon lamp may then produce in one instance, an amber color, or in other instance, a red color without the cold environment problems typical of a mercury based lamp. The output efficiency is enhanced when the lamp is formed as an aperture lamp. The narrow source is also useful as a source in reflector and lens systems. High pressure neon lamps offer a small source size, direct color with no filtering, good tolerance of impact and jarring, moderate cost, and increased vehicle styling potential.

Abstract: An incandescent lamp includes a base, a first stiff lead-in wire and a second stiff lead-in wire, a connector, a filament and a non-opaque tubular envelope. The base is formed out of a non-conductive material. The first and second stiff lead-in wires, respectively, extend from the base. The connector is electrically coupled to the first and second stiff lead-in wires and mechanically coupled to the base. The filament has a first end and a second end which are electrically coupled to the first and second lead-in wires, respectively. The filament is formed out of a conductive wire in the shape which provides a radiation area which is similar to the illumination area of the bundle of optical fibers so that the radiation fills the illumination area within the geometric boundaries imposed. The non-opaque tubular envelope has an open end and a closed end and is mechanically coupled to the base at the open end. The base press-seals the non-opaque tubular envelope to form an enclosed chamber.

Abstract: Electrodeless, low pressure, fluorescent discharge lamp of high aspect ratio, with a substantially flat spiral rf coil adjacent a back face (and insulated therefrom), that emits light through a front surface or selected portions under control of internal reflective and phosphor coatings placement to afford minimum resonance trapping, high efficiency and uniform illumination of high specific intensity over a selected area of the front wall.

Abstract: Multiple concentric, triangular cross-sectioned fluorescent lamp tubes, located substantially in the same plane with respect to each other, are utilized in appropriate assemblies for: 1) a direct screw-in replacement for reflective incandescent lamps and; 2) recessed ceiling fixtures that are typically hardwired. The inherent triangular geometries of the concentric, substantially same plane lamps create mutually benefiting reflecting surfaces to maximize the net light output. The triangular geometry enables light from two sides of the fluorescent tubing to be efficiently cast if desired (or muted by absorbent housing wall if desired). The remaining side, or base, of each triangular tube produces light that is redirected by opposing, intersecting, coaxial, conical reflectors arranged to direct the light through the unobstructed center of the concentric tubing arrangement. A transparent collimating structure adjacent to the triangular tub bases is used to enhance control of the light emanating from the base.

Abstract: A planar fluorescent and electroluminescent lamp having two pairs of electrodes. Planar electrodes on an outer surface of the lamp create a plasma arc by capacitive coupling. The planar electrodes also cause embedded phosphor to emit light on the electroluminescent phenomena. In one embodiment, a second chamber is on top of the first chamber and light passes from a primary chamber through the second chamber, and is emitted by the lamp.

Abstract: To provide a sealed through arrangement for electrical leads through a ceramic end plug, suitable for discharge lamps of between about 50 to 250 W power rating, the lead-through (9) is made of a material having a thermal coefficient of expansion which is substantially less than that of a ceramic sealing plug (10), for example of tungsten, molybdenum or rhenium, but so small that the individual, actual expansion of the ceramic material will not cause separation from the metal, and/or a glass melt, ceramic melt or sintar connection therewith. The electrical connection is formed by at least two, and preferably more than two, thin wires or pins (23) having a diameter, each, of up to only about 0.25 mm, and preferably less. Each of the wires, then, will carry currents in the tenths ampere ranges, sufficient for operation of the lamp, and passed through melt-sealed capillary openings in the ceramic sealing plug (10).

Abstract: Disclosed is an electrodeless, low pressure gas discharge lamp. The lamp includes a vitreous envelope containing a metal vapor and an inert gas. The envelope is shaped with an external chamber for receiving an electrical excitation circuit. The excitation circuit is effective for exciting the metal vapor to emit light with electromagnetic fields that are passed through the vitreous envelope from outside, to inside, the envelope. A circuit supplies electrical power from power mains to the excitation circuit. A transparent, electrically conductive coating is disposed on the inner surface of the vitreous envelope for suppressing electromagnetic interference on the power mains. An electrically conductive coating is disposed on the outer surface of the vitreous envelope; it is capacitively coupled to the inner conductive coating, via a wall of the vitreous envelope, and is maintained at a suitable potential for suppressing electromagnetic interference on the power mains.

Abstract: An electric lamp has a lamp vessel (2) mounted in an outer bulb (1). A glass containment sleeve (10) surrounds the lamp vessel and is fused to a tipped off exhaust tube (5). A coiled wire (11) surrounds the sleeve 10 and provides further containment. The wire may be fixed to the sleeve (10) by clamping fit. The construction of the lamp is simple and effective to protect the outer bulb (1) from being damaged by an explosion of the lamp vessel (2).

Abstract: The electric discharge lamp has a discharge vessel, which is mounted in an outer bulb. A containment shield surrounds the discharge vessel and includes a glass sleeve and a helically coiled wire about the sleeve. Electrically isolated clamping leads extending from the seals axially secure the glass sleeve about the discharge vessel so that it is electrically isolated. The wire is fixed around the sleeve in an electrically floating manner, e.g. by clamping fit and/or by bent end portions secured over the ends of the glass sleeve. The construction of the lamp is simple and effective to protect the outer bulb from being damaged by an explosion of the lamp vessel and to prevent accelerated sodium depletion from the discharge vessel.

Abstract: A low pressure discharge lamp having a tubular discharge vessel (1). At each of its end portions (2, 3) the vessel (1) is fused to a respective metal tube (5) having an uncovered outer surface outside the vessel. A sealed glass tube (6) is fused to the metal tubes (5). Ignition aids (18, 28, 40) may also be present. The simple construction of the lamp permits manufacture and high lamp quality, even at long lengths and/or small diameters of the discharge vessel. The lamp may have an ionizable filling of rare gas or may also contain mercury. A fluorescent powder may also be present in the discharge vessel. The lamp (72) and a luminaire (70, 71) mounting the lamp may be used for display or signalling purposes.

Abstract: An electrodeless high intensity discharge (HID) lamp arc tube having a stabilized condensate location. The arc tube contains a predetermined location or distortion on the inside surface of the arc tube. The distortion may be a protrusion on the inside surface of the arc tube formed during the arc tube forming process. In operation of the lamp, the non gaseous dose remains condensed substantially in the cold spot region formed by said protrusion so that the arc tube walls remain clear for maximal light output, and the arc tube remains stable and efficacious to substantially higher power than is the case for arc tubes without the distortion.

Abstract: To optimize operating conditions with respect to overall size of a high-psure discharge lamp having a metal halide fill, the wall thickness (d) in millimeters is selected in accordance with a theoretical optimum relationship of d=1.5+0.1.times..cuberoot.P, in which P is the power rating of the lamp, in watts. The optimal theoretical thickness should not vary by more than .DELTA.d=.+-.0.2.times..sup.d, in millimeters, from the theoretical optimal value, with lower power ratings permitting a thinner wall thickness than higher power ratings. Optimizing the wall thickness improves the color rendition index and the light distribution of the emitted light, as well as decreasing the devitrification of the quartz glass of the discharge vessel.

Abstract: A planar fluorescent and electroluminescent lamp having two pairs of electrodes. Planar electrodes on an outer surface of the lamp create a plasma arc by capacitive coupling. The planar electrodes also cause embedded phosphor to emit light on the electroluminescent phenomena. In one embodiment, a second chamber is on top of the first chamber and light passes from a primary chamber through the second chamber, and is emitted by the lamp.

Abstract: A source of IR-radiation, having an enclosure defining between its walls a sealed-off, electrode-less chamber, the walls having at least one portion transparent to IR-radiation, and the chamber containing a gas mixture of at least one, molecular, IR-active gas, of at least one buffer gas and of at least one noble gas. A method for producing a source of IR-radiation is also described and claimed.

Abstract: In a UV high-power radiator, a plurality of dielectric tubes (6) having internal electrodes (7) are disposed in the interior of a quartz housing having rectangular cross section. The interior of the housing is filled with a filling gas which emits UV radiation under discharge conditions. The electrical supply is provided in such a way that the discharges (17) develop between adjacent dielectric tubes (6). A notable feature of this construction is its compactness, economical nature and service friendliness.

Abstract: A source of red light includes a double-bore capillary tube having a pair of ends and a convoluted shape. A pair of electrodes is located at one end of the capillary tube and disposed within respective bores. An ionizable medium is enclosed within the capillary tube and includes neon at a pressure from about 300 to 600 torr. When energized, the ionizable medium generates an arc discharge between the electrodes consisting primarily of radiation in the range of from 590 to 670 nanometers. An outer jacket of vitreous material may surround the capillary tube and contain an inert gas (e.g., nitrogen) at a predetermined pressure.

Abstract: The invention provides a ceramic electric-discharge lamp having a pinch-sealer which is set to an end of an outer envelope and covered by a base having a pair of base pins projecting themselves into the base. The outer envelope is in vacuum, in which an arc tube composed of a square U-shaped tube is installed. Apertures of both ends of the square U-shaped illuminant are closed by ceramic discs each containing an electrode. Linear illuminant is formed in such regions where the radius of curvature of the square U-shaped arc tube greatly varies, in other words, between the curved portions.

Abstract: The high-power radiator includes a discharge space (12) bounded by a metal electrode (8), cooled on one side, and a dielectric (9) and filled with a noble gas or gas mixture, both the dielectric (9) and also the other electrode situated on the surface of the dielectric facing away from the discharge space (12) being transparent for the radiation generated by quiet electric discharges. In this manner, a large-area UV radiator with high efficiency is created which can be operated at high electrical power densities of up to 50 kW/m.sup.2 of active electrode surface.

Abstract: A noble-gas flashlamp having a self-replenishing mercury-pool cathode. The lamp includes a lamp envelope which is transparent to UV radiation and which forms a linearly extending discharge chamber for holding a noble gas discharge material. At the cathode end of the discharge chamber the envelope forms a cavity or bubble communicating with the discharge chamber. The cathode of the lamp is formed by a cathode electrode and a pool of liquid mercury in the cavity. The electrode is both electrically and thermally conducting, and the pool of liquid mercury covers the electrode and is in heat exchange relation with the electrode in the cavity. For enhanced heat transfer the cathode electrode extends beyond the lamp envelope so that it may be brought into direct contact with the lamp coolant material. The anode comprises an electrically and thermally conducting anode electrode at said anode end of the discharge chamber.

Abstract: A miniature, low-wattage fluorescent lamp includes a double-bore inner capillary tube having a pair of ends and a convoluted shape. The inner capillary tube is comprised of a vitreous material (e.g., quartz) which is capable of transmitting ultraviolet radiation. A pair of electrodes (e.g., mercury pool) is located at one end of the inner capillary tube and disposed within respective bores. An ionizable medium is enclosed within the inner capillary tube and includes an inert starting gas and a quantity of mercury. When energized, the ionizable medium generates an arc discharge between the electrodes consisting of ultraviolet radiation. A phosphor coating responsive to the ultraviolet radiation is disposed on an outer surface of the inner capillary tube and remote from the arc discharge. An outer jacket of vitreous material surrounds the inner capillary tube and contains an inert gas at a predetermined pressure.

Abstract: A gas discharge display apparatus in the form of an electroluminescent gas filled panel adapted for quickly and inexpensively making a durable and robust luminous sign using image patterns transferred to the panel by painting, silkscreening, stencilling, lithography, or the like. The apparatus generally includes a pair of substantially parallel spaced apart rigid plates, or sheets, enclosing an electroluminescent gas, and having variously located and kinds of conductive elements, such as surface coatings, used as electrodes for energizing the enclosed electroluminescent gas.

Abstract: A high pressure sodium discharge lamp having an arc tube mounted within a lamp envelope and having a resistor connected electrically in series with the arc tube. An insulative body is provided between the arc tube feed-through closest to the stem and a rigid conductor for axially supporting the arc tube and electrically insulating the feed-through from the rigid conductor. The series flicker-elimination resistor is mounted adjacent the lamp stem and electrically shunts the insulative body. An integral thick film resistor which includes the series resistor and a starting resistor for a starting circuit has optimized terminal placement for simplifying mount construction.

Abstract: A fluorescent lamp of a hot cathode type which is operated with a lamp current of 50 mA or less comprises an outer tube as an envelop, a gas filled in the envelop and a pair of electrodes disposed at both ends of the outer tube in an opposing fashion, at least one of the electrodes being operated in a hot cathode mode. With the fluorescent lamp of the type described, a following relationship is established, p.d.gtoreq.13, where d represents an inner diameter (cm) of the envelop and p represents an inner pressure (Torr) of the gas filled in the envelop. When the relationship V.sub.k .ltoreq.15, where V.sub.k represents a cathode fall voltage, is further satisfied, the life time of the fluorescent lamp can be elongated.

Abstract: The invention relates to a high-pressure sodium discharge lamp which under nominal operating conditions radiates white light with a maximum color rendering index R.sub.a of more than 80. Since the wall load is above 80 W/cm.sup.2 under nominal operating conditions, a color temperature T.sub.c of at least 2800.degree. K. can be achieved with a luminous efficacy of more than 40 lm/W.

Abstract: The high pressure discharge lamp has containment structure in the outer envelope which encloses the discharge vessel. The containment structure consists of a glass cylindrical sleeve closed at its ends by a metal plate. The plates, the cylindrical sleeve and the discharge vessel are combined as a subassembly. The metal plates are provided with tongues bearing on the glass cylindrical sleeve and the outer envelope. The lamp has a flexible conductor which extends from the current lead-through conductor remote from the stem to the lamp stem and bears on the outer envelope. The containment structure prevents failure of the outer lamp envelope in the event of explosive failure of the discharge vessel.

Abstract: A high pressure sodium discharge reflector lamp having a blown glass outer envelope. The outer envelope contains a rare gas having a fill pressure slightly less than one atmosphere and a pressure at lamp operating temperature of approximately one atmosphere for implosion protection.

Abstract: A low pressure mercury vapor discharge lamp having a double-tube type discharge vessel consisting of a closed outer glass bulb and an inner glass tube coaxially disposed within the outer bulb. An electrode is disposed in the inner glass tube, while a ring-shaped electrode structure is disposed in the outer envelope outside the inner glass tube. The electrode structure completely surrounds the inner glass tube and includes a pair of lead-in wires and a pair of semicircular electrode sections. Preferably, an inert gas having a pressure within the range of from about 4.0 to 6.0 torr and a quantity of mercury are contained within the lamp. The lamp of the present invention provides a fully diffused discharge without requiring an expensive transistor switching circuit or a permanent magnet to rotate the discharge about the inner tube.

Abstract: To protect the quartz of a quartz glass bulb (2) from attack by alkaline earth oxides emitted from electrodes (6) of the lamp, and prevent deterioration of the quartz in use of the lamp with respect to transmission of ultraviolet (UV) radiation, particularly in the short wave length range of 200 nm to 250 nm, boron silicate glass or glass-like aluminum oxide, or a mixture of boron silicate glass and glass-like aluminum oxide is interposed between the quartz bulb (2) and the electrodes. Boron oxide can be applied to the interior of the quartz bulb, and fired thereon to form, for example, a boron silicate glass layer (4) or diffuse into the quartz glass to form a diffusion layer (4') by suitable selection of firing temperatures. Alternatively, an aperture support element (35, 45) can retain a disk of boron silicate glass or glass-like aluminum oxide positioned between the electrodes and the quartz glass bulb.