Abstract: The discharge lamp has a discharge tube filled with a fill gas and sealed in a gas-tight manner and a cap part made to be suitable for connection to a socket. This cap part has a housing made by a shell and a closing member fixed thereto, and electrical contact components. The shell has openings for receiving the end portions of the discharge tube legs into the housing and the shell is made to be suitable for supporting the discharge tube mechanically. The electrical contact components are embedded in the housing and connected in the inner space of the housing to the electrodes of the discharge lamp and protrude from the cap part. The cap part contains mechanical support component(s) for fixing the discharge lamp in the socket.

Abstract: A ballast circuit for a gas discharge lamp contained within a resonant load circuit has resistively heated cathodes. A d.c.-to-a.c. converter circuit supplyies a.c. current to the resonant load circuit. The converter circuit comprises first and second switches serially connected between a bus conductor at a d.c. voltage and a reference conductor, and has a common node through which the a.c. current flows. In an arrangement for controlling the converter switches, a comparator circuit compares a signal on a first input node with a periodic reference signal on a second input node, and produces a comparator output signal that changes state when a first one of the compared signals becomes greater than the second of the compared signals, and that further changes state when the second of the compared signals then becomes greater than the first of the compared signals. A circuit generates the periodic reference signal in response to the comparator output signal.

Abstract: An electrodeless fluorescent lamp having an emission suppression arrangement utilizing a capacitive filtering element formed by a first conductive layer disposed on a portion of the interior surface of the lamp envelope, a second conductive layer on a corresponding external portion of the lamp envelope and the glass material of the lamp envelope disposed therebetween, achieves significant emission reduction yet at the same time reduces eddy current losses otherwise occurring at the second conductive coating portion of the capacitive filtering element. A plurality of slots formed in the second conductive coating are effective so as to reduce the circular flow of eddy currents around the second conductive layer, such eddy currents as would otherwise adversely affect the Q of the circuit.

Abstract: Disclosed are optical couplers and optical coupling systems for coupling a source of non-coherent light to a light distribution harness, wherein the couplers are polygonal in cross section to increase light mixing. The couplers have inlet and outlet arms, and an intermediate bend region configured to achieve compactness and minimal light loss through the bend region. In one embodiment, the bend region is an integral part of the coupler, with the inlet arm having a different cross-sectional dimension from the outlet art in such manner that substantially all light directed from the inlet portion to the bend portion reaches the outlet arm portion, and light rays parallel to the inlet axis are reflected in the bend portion to be directed substantially parallel to the outlet axis. In a second embodiment, the bend region comprises a prism having a pair of parallel spaced surfaces, and inlet, outlet, and third surfaces that are non-parallel to the spaced surfaces.

Abstract: An electrodeless fluorescent lamp having a lamp envelope with an inner phosphor coating and containing a fill capable of sustaining a discharge when suitably excited by an electric field includes an electrically conductive coating on the exterior of the lamp envelope. The electrically conductive coating is also light transmissive and is effective for confining the electric field to within the lamp envelope.

Abstract: A ballast circuit for a gas discharge lamp comprises a resonant load circuit incorporating the gas discharge lamp and including a resonant inductance and a resonant capacitance. A d.c.-to-a.c. converter circuit induces an a.c. current in the resonant load circuit. The converter circuit comprises first and second switches serially connected between a bus conductor at a d.c. voltage and a reference conductor, and which are connected together at a common node through which the a.c. load current flows. The first and second switches each comprise a control node and a reference node, the voltage between such nodes determining the conduction state of the associated switch. The respective control nodes of the first and second switches are interconnected. The respective reference nodes of the first and second switches are connected together at the common node.

Abstract: A cap for securing a plurality of discharge tubes to a discharge lamp assembly includes a pair of ribs formed on a base plate of the cap. The ribs guide adhesive towards openings in the base plate through which the tubes extend. Adhesive is kept away from the base plate perimeter, which may include a rim, such that assembly of the cap with a housing does not upset the adhesive bond securing the discharge tubes to the cap. Similarly, an assembly method for the cap involves the step of forming a pair of ribs on the base plate of the cap.

Abstract: A low pressure discharge lamp, particularly a compact fluorescent lamp, achieves substantially the same base-down lumen output as base-up lumen output. The lamp does so in a bent and bridged configuration, preferably in the shape of a plurality of vertically oriented bent tubes horizontally bridged together, where at least one of the tubes has at least one extended leg that defines a cold chamber within or adjacent the base.

Abstract: The invention relates to a single-ended discharge lamp having a lamp envelope comprising at least two tube legs, and a housing portion designed for mechanical and electrical connection to a lamp socket, which housing portion consists of a tube supporting part, a connection part and a screw base, which parts are linked together. Holes are made in the tube supporting part into which holes the legs of the lamp envelope are placed and the ends of the legs of the lamp envelope being inside the housing portion are fixed with a bonding material applied to the outside lamp envelope portion of the tube supporting part which portion surrounds the lamp envelope.The essential feature of the invention is that the ends of the tube legs of the lamp envelope being inside the housing portion are fixed to the tube supporting part with a bonding material being also applied to the inside portion of the tube support part, which inside portion is bordered by the tube legs.

Abstract: A reflector lamp unit is provided having a light source which is capable of meeting the efficiency requirements mandated by law. The reflector lamp unit includes a pressed glass reflector member having a curved portion and a lower neck portion on which is secured a conventional threaded screw base. The light source can be a high efficiency light source such as a discharge light source of a tungsten-halogen light source contained within a pressurized lamp envelope. The light source is disposed within the curved portion of the reflector member at a position along the longitudinal axis and ahead of the optical focal point of the reflector. In this manner, a beam pattern is generated which is widely scattered and unfocused as compared to that beam pattern which would be produced from a light source disposed at the focal point. The reflective surface of the curved portion of the reflector member is lightly roughened thereby resulting in an increased diffusion characteristic of the beam pattern.

Abstract: A compact fluorescent lamp having improved warm-up characteristics is provided. The lamp includes a sealed glass envelope formed from U-shaped tubes each having a pair of substantially parallel leg sections closed at one end and a transversely extending bridging section joining the other end of the leg sections. Adjacent leg sections of adjacent tubes are joined by connecting conduits which complete a convoluted and elongate discharge path between a pair of electrodes. A main amalgam located within in a sealed stem at a closed end of an interior leg section for controlling mercury vapor pressure during a discharge period except for a starting period thereof. Auxiliary amalgams are attached to electrode support structures extending from the closed ends of the exterior leg sections for emitting mercury vapor during the starting period.

Abstract: A low pressure mercury vapor discharge lamp is provided, having a non-straight glass envelope and a plurality of rare earth phosphor layers coated inside the glass envelope. The lamp is made by coating a plurality of rare earth phosphor layers inside a straight glass tube. The tube is then formed into a non-straight configuration, each layer being sufficiently thin so that the phosphor coating does not flake off in sections where the tube is bent around a radius of curvature. A plurality of thin rare earth phosphor layers will not flake off in the bent section whereas a single thick rare earth phosphor layer will flake off. The invention is particularly useful in the manufacture of helical compact fluorescent lamps.

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: A reflector fluorescent lamp with a reflective layer between the light-transmissive envelope and the phosphor layer(s). The reflective layer has a coating weight of at least 5, more preferably 6-8, mg/cm.sup.2 and is a blend of gamma alumina and alpha alumina, preferably 7-80 weight percent gamma alumina and 20-93 weight percent alpha alumina, more preferably 30-40 weight percent gamma alumina and 60-70 weight percent alpha alumina. The reflective layer finds particular utility in an electrodeless fluorescent lamp.

Abstract: A ballast circuit for a gas discharge lamp of the type including resistively heated cathodes includes a resonant load circuit incorporating a gas discharge lamp and including first and second resonant impedances whose values determine the operating frequency of the resonant load circuit. Further included is a d.c.-to-a.c. converter circuit coupled to the resonant load circuit so as to induce an a.c. current in the resonant load circuit. The converter includes first and second switches serially connected between a bus conductor at a d.c. voltage and ground, and has a common node through which the a.c. load current flows. A feedback circuit provides a feedback signal indicating the level of current in the resonant load circuit.

Abstract: A metal halide arc discharge lamp includes a sealed outer envelope, an arc tube located within the envelope, a cylindrical shroud positioned around the arc tube, stops positioned at ends of the shroud to capture the shroud therebetween, conduction wires which both provide electrical energy to the arc tube and mechanically support the arc tube and the shroud, and a compression spring secured by an eyelet for removing tension loading from the arc tube.

Abstract: A ballast for a gas discharge lamp comprises a resonant load circuit including a gas discharge lamp, and a resonant inductance and a resonant capacitance whose values determine the operating frequency of the remnant load circuit. A d.c.-to-a.c. converter circuit is coupled to the remnant load circuit to provide a.c. current to the remnant load circuit. The converter comprises at least one switch. A high voltage IC drives the at least one switch at a frequency determined at least in part by impedance between a timing input and a ground. A circuit for supplying a d.c. voltage to the d.c.-to-a.c. converter includes (i) a supply path for d.c. current; (ii) first and second return paths for d.c. current; and (iii) an arrangement to selectively make the first return path operable alone, the second path operable alone, and the first and second paths operable together. First and second impedances are coupled between the timing input and the first and second return paths, respectively.

Abstract: A ballast circuit for a gas discharge lamp includes a resonant load circuit incorporating a gas discharge lamp and including first and second resonant impedances whose values determine the operating frequency of the resonant load circuit. Further included is a d.c.-to-a.c. converter circuit coupled to the resonant load circuit so as to induce an a.c. current in the resonant load circuit. The converter includes first and second switches serially connected between a bus conductor at a d.c. voltage and ground, and has a common node through which the a.c. load current flows. A feedback circuit provides a feedback signal indicating the level of current in the resonant load circuit.

Abstract: A ballast circuit for a gas discharge lamp comprises a resonant load circuit incorporating a gas discharge lamp and including first and second resonant impedances whose values determine the operating frequency of the resonant load circuit. A d.c.-to-a.c. converter circuit is coupled to the resonant load circuit to induce an a.c. current in the resonant load circuit. It comprises first and second switches serially connected between a bus conductor at a d.c. voltage and ground, with a common node through which the bidirectional load current flows. An arrangement allows a user to select a setpoint signal during lamp operation that determines the amount of light output by the lamp. A feedback arrangement regeneratively controls the first and second switches; it includes a circuit for sensing a.c. current in the resonant load circuit and producing an a.c. feedback signal in proportion to the a.c. current; a circuit for producing a d.c.

Abstract: The invention relates to a single-ended discharge lamp with circuitry in its housing base. The discharge lamp includes a discharge tube and a housing. The discharge tube is provided with electrodes containing a fill and sealed in a gas-tight manner. The housing base contains circuitry mounted on a circuit board and providing for the operation of the discharge tube. The housing base is built from two parts, a base and a cap, fixed to each other. The housing base is formed in a way suitable for mechanical and electrical connection to a lamp socket on one part, and for mechanically fixing the discharge tube and connecting the output terminals of the circuitry to the electrode inleads of the discharge tube on the other part. The circuit board is inserted between supports formed in the inside of and protruding from one part of the housing base. One feature of the invention is that longitudinal ribs are formed on the support and protrude from the support.