Abstract: In a high intensity metal halide discharge lamp utilizing thorium in conjunction with a transport cycle for electrode activation, a getter, preferably cadmium or zinc is added to the lamp fill for the purpose of reducing the concentration of free iodine during operation. By so doing, deposition of thorium on the electrode tip during operation is assured and performance and maintenance are improved. The quantity of getter may include a portion supplied as a corrective measure to scavenge excess iodine released during manufacture, and another portion providing a long-term buffering capacity for capturing iodine released during the lamp's life by reaction of the dose, particularly ScI.sub.3 and ThI.sub.4, with the SiO.sub.2 of the lamp envelope.

Abstract: Improved seating or mounting pads are provided in a plastic reflector for a parabolic aluminized reflector (PAR) lamp and, in particular, hollow mounting pads are located at each corner of a rectangular shaped plastic reflector member to avoid deformation of the parabolic cavity when the reflector member is formed. In a preferred embodiment, the reflector member is of a unitary molded construction which further includes a sealing rim and with said mounting pads comprising semi-circular hollow boss elements which are located on the rear surface of said sealing rim and project backwardly therefrom to terminate on the parabolic cavity surface.

Abstract: An improved plastic reflector member for a parabolic aluminized reflector (PAR) lamp is disclosed and, in particular, use of said improved plastic reflector member for an all plastic PAR lamp or a PAR lamp which uses said improved reflector member. Said improved plastic reflector member utilizes a variable thickness wall member to form the parabolic shaped cavity wherein the wall thickness is sufficiently greater in the apex region of said parabolic cavity than in the adjoining wall region to avoid mechanical and heat distortion.

Abstract: Static inverter comprises a transformer and transistor for intermittent asymmetric energization of the transformer. The transformer includes three feedback windings which in response to saturation of a branch of the transformer core but before full core saturation discontinue regenerative feedback and then apply degenerative feedback. A fourth feedback winding in the transformer assures commutation and re-triggering of the transistor.

Abstract: Starting and operating circuit for gaseous discharge lamps has device for quickly re-starting extinguished lamps while still hot. Circuit comprises a source of alternating current, an inductive regulator ballast having its input connected to the alternating current source, and a gaseous discharge lamp connected to the output of the ballast, a sine wave oscillator circuit having its input connected to the current supply and having its output connected to a transformer connected in series between the ballast and the lamp for stepping up and applying voltage to a lamp, the oscillator circuit comprising a transistor switch and an oscillator transformer connected to the step-up transformer for producing a high voltage, high frequency sine wave for starting and re-starting the discharge lamp. The operation of the oscillator circuit is improved by a turn-off circuit comprising series-connected diode and inductor connected to the transistor and the oscillator transformer.

Abstract: Luminaire has refractor with a hinged door to provide access to the enclosed lamp for re-lamping operations. A prismatic optical device is provided on the luminaire to indicate when the door is fully closed on the refractor.

Abstract: A photoflash lamp array comprising a housing elongated vertically and containing elongated flash lamps lying horizontally and stacked vertically, the flash lamps having lead-in wires extending from ends thereof near the sides of the housing and connected to a circuit board located behind the lamps. A conductive sheet-like shield is positioned between the circuit board in the rear of the housing and is contoured to have side portions extending forwardly in between lamp ends and the sides of the housing. The front surface of the shield is both electrically conductive and reflects light with electrically insulated flash indicator material being positioned on said front surface but not extending to the side portions thereof. By increasing the light reflective surface of said shield member in this manner there is increased light output obtained from said lamp array.

Abstract: This invention relates to polymer sealed beam headlamp units having trim rim reference planes integrally molded therewith. The headlamp includes a polymer envelope having a reference plane integrally molded with the reflector portion of the envelope which projects radially outward and forward therefrom for providing a precise reference plane forward of the lamp face.

Abstract: A high intensity discharge lamp comprises a two-electrode arc tube and an external starting probe supported from a base and preferably sealed within an outer envelope to which the base is attached. The base contains an electronic pulsing circuit comprising a capacitor connected in a charging circuit across the base terminals, a pulse transformer having its primary connected in series with a voltage sensitive switch across the capacitor, and a step-up secondary connected to the probe. After starting, the voltage across the capacitor drops below the breakdown level of the switch and pulsing stops.

Abstract: A U-shaped discharge lamp, such as a fluorescent lamp, is provided with a starting strip in the form of a pair of conductors respectively extending partially along the legs of the lamp, and an electrical connection is made between the conductors at one end thereof. This electrical connection can consist of or be combined with a support strap. An additional starting strip component can be provided on the U-bend portion of the lamp.

Abstract: A circuit for starting and ballasting a compact high-intensity arc discharge lamp. A filament connected in series with the arc lamp provides illumination during arc start-up and functions as a ballast during normal arc operation. An oscillatory starting circuit includes a transformer and a frequency-controlling ringing circuit, and applies starting voltage to the arc lamp until an operating arc is established. The circuit includes capacitor means for isolating the starting transformer from the operating path of the arc lamp, and further includes a voltage-doubling starting circuit and also a "keep-alive" feature which prevents the arc from extinguishing during power fluctuations.

Abstract: A compact lamp unit and associated socket for use in a projection system such as a slide projector, microfilm viewer, and so forth. The lamp unit includes a reflector molded from a plastic material and an electric lamp secured within the reflector. In order to decrease the axial dimension of the reflector and to avoid the use of pin connectors, electrical contacts for the lamp are pressed into recesses formed in the outer surface of the reflector. The reflector includes an opening at its apex through which electrical leads from the lamp extend outwardly of the reflector. The electrical leads are secured to the contacts by being forced into the recesses along with the contacts. This construction technique is fast and simple.The lamp unit also includes a handle to enable a heated lamp unit to be replaced by the user and a guide means to enable the lamp unit to be oriented quickly and accurately upon insertion into the socket.

Abstract: A compact lamp unit and associated socket for use in a projection system such as a slide projector, microfilm viewer, and so forth. The lamp unit includes a reflector molded from a plastic material and an electric lamp secured within the reflector. In order to decrease the axial dimension of the reflector and to avoid the use of pin connectors, electrical contacts for the lamp are pressed into recesses formed in the outer surface of the reflector. The reflector includes an opening at its apex through which electrical leads from the lamp extend outwardly of the reflector. The electrical leads are secured to the contacts by being forced into the recesses along with the contacts. This construction technique is fast and simple.The lamp unit also includes a handle to enable a heated lamp unit to be replaced by the user and a guide means to enable the lamp unit to be oriented quickly and accurately upon insertion into the socket.

Abstract: This invention relates to polymer sealed beam headlamp units having rims integral therewith, and more particularly to a unitary coupling assembly for securing these headlamp units to vehicles. The assembly includes an integrally rimmed headlamp having a plurality of couplers secured thereto. The couplers are integrally molded with the rim or attached thereto. The couplers have curved mating surfaces, centered about point for pivotal movement, which engage the surfaces of complementary couplers secured to a vehicle. The couplers are lockingly secured to each other and form a coupling for attaching the lamp to a vehicle. In a preferred embodiment the assembly employs adjustable couplers for the adjustable and/or preaimed attachment of a headlamp to a vehicle.

Abstract: This invention relates to sealed beam headlamp units and more particularly to a unitary coupling assembly for securing these headlamp units to vehicles. The assembly includes a headlamp having a plurality of couplers secured to the exterior surface thereof. The couplers have curved mating surfaces, centered about point for pivotal movement, which engage the surfaces of complementary couplers secured to a vehicle. The couplers are lockingly secured to each other and form a coupling for attaching the lamp to a vehicle. In a preferred embodiment the assembly employs adjustable couplers for the adjustable and/or preaimed attachment of a headlamp to a vehicle.

Abstract: Various rare earth phosphor admixtures are described utilizing thulium-activated oxyhalides of lanthanum and/or gadolinium to provide improved performance in x-ray image converter devices. These phosphor admixtures are used in radiographic screens in combination with either blue sensitive or green sensitive photographic film.

Abstract: A circular fluorescent lamp unit having a compact central hub containing a ballast reactor and provided with a screw base. A replaceable circular lamp assembly is positioned around and attached to the hub.

Abstract: An integrally connected fluorescent lamp and ballast unit having an elongated ballast of wire wound around and along an elongated magnetizable core and extending alongside an elongated lamp bulb. The elongated lamp and ballast can be straight, or can be curved. The ballast provides a combined resistive and inductive ballasting impedance for the lamp.

Abstract: Rare earth oxyhalide phosphors activated with terbium and/or thulium ion are described exhibiting improved brightness which are particularly useful in x-ray image converter devices by reason of producing less light scattering and absorption as a result of superior crystalline characteristics. A multilayer x-ray screen construction utilizing said phosphor material is also described utilizing said phosphor material which exhibits improved image sharpness and a reduced crossover problem. An improved process for producing said phosphor material is further disclosed wherein the selected oxyhalide is recrystallized in a molten alkali metal halide flux to produce the superior crystalline characteristics.

Abstract: This invention relates to multiple coiled incandescent filaments and more particularly to a single strand filament wire, coreless, triple-coil filament for an incandescent lamp having mandrel ratios in either or both its second or third coiling less than 1.0.