Abstract: The lighting circuit comprises an AC input connectable to receive an AC input voltage, a switched LED array comprising a plurality of LEDs reconfigurable into a plurality of configurations and having an input for receiving a LED driving voltage, a switched capacitor array having an input for receiving a charging voltage and an output selectively connectable to the input of the switched LED array and comprising a plurality of capacitors and switches connected to selectively couple the capacitors across the input or output, a first switched rectifier connected between the AC input and the switched LED array, a second switched rectifier connected between the AC input and the switched capacitor array, and, a control system configured to monitor the AC input voltage and control the switched LED array, the switched capacitor array and the first and second switched rectifiers based on the AC input voltage and a desired light output.

Abstract: Intensive microwave radiation in particular of great band width and energy over a relatively long period of time in the form of long pulse packets with a high pulse repetition frequency and a very high frequency spectrum can be achieved if microwave irradiation is effected during the discharge of a capacitive high-voltage generator (35) by way of the antenna (26) into a series of successive capacitors (13) to be connected in parallel. They are preferably constructed in the form of a concentric stack, connected to the antenna (26), of which the outer electrodes (16) which are at a reference potential are in the form of a continuous tube within which annular electrodes (15) are disposed on a carrier (20) in axially spaced relationship with each other in such a way that at the same time they act as the electrodes of arc switches (39) for successively switching on subsequent capacitors (13).

Abstract: The invention relates to a high-pressure discharge lamp of the ceramic metal halide type of the Philips MasterColor series having a molybdenum coil wrapped around the discharge vessel and at least a portion of the electrode feed through means, and having power ranges of about 150 W to about 1000 W. Such lamps are provided with a discharge vessel which encloses a discharge space. The discharge vessel has a ceramic wall and is closed by a ceramic plug. An electrode which is located inside the discharge space is connected to an electric conductor by way of a leadthrough element. The leadthrough element projects through the ceramic plug with a close fit and is connected thereto in a gastight manner by way of a sealing ceramic. The leadthrough element has a first part which is formed by a cermet at the area of the gastight connection.

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: An improvement to the current-carrying components of a lamp includes two filaments connected to two different electrodes and one common electrode, and a switch for directing current through the secondary filament upon the failure of the primary filament. Normally, the current flows through the primary filament. The switch in one embodiment is a wire that does not conduct when the primary filament is operational but conducts on the failure of the primary filament to shunt the current to the secondary filament. The wire is an oxide metal wrapped around two of the three electrodes inside the glass envelop of the lamp. When the primary filament fails, the open circuit voltage breaks across the oxide layer to weld the wire to the electrodes and bypass the primary filament.

Abstract: In a glow discharge starter, a layer of lanthanum is present on one of the conductors and the gas filling is a Penning mixture. The glow discharge starter does not contain radioactive material. The delay time between the application of a voltage between the conductors and establishing a glow discharge remains short during the whole life of the glow discharge starter, even when the starter was kept in a room with a low light level for a prolonged time.

Abstract: The circuit for firing and supplying a discharge lamp, includes:a load circuit (10), with at least one discharge lamp (L) and a voltage supply for supplying a discharge lamp,a subportion of the circuit is in parallel with the lamp (L). This subportion includes at least one arrangement of capacitors (17, 21) and an inductive impedance which can be varied in a controllable manner in order to modify the value of the total impedance in parallel with the lamp.

Abstract: A high-pressure discharge lamp includes a discharge vessel which is enclosed with intervening space by an outer bulb. The lamp is provided with a starter circuit constructed as a starter unit comprising a bimetal switch and glow switch starter. The bimetal switch has a bimetal element which is fastened with a fastening point to a conductor, and rests in the cold state against a break contact point of a break contact. The fastening point and the break contact point form part of an insulating rigid body.

Abstract: A glowbottle starter switch for igniting gaseous discharge lamps in alternating current circuits. The glowbottle including a hermetically sealed glass envelope (7) containing a fill of an ionizable gas and having at least two lead wires (2,3) disposed therein and extending to the exterior of the envelope (7) and a bimetal switch (4) disposed on at least one of the lead wires (3). The switch (4) is arranged to move within a gap to contact the other of the lead wires (2). An electroluminescent light emitter including an electroluminescent phosphor (6 in FIG. 1) is disposed in optically-contiguous relationship with the glowbottle. The electroluminescent light emitter is arranged to be energized to emit light by electric fields produced by alternating voltage between the lead wires (2,3).

Abstract: A high pressure discharge lamp having a thick film resistor comprising a plurality of resistive elements. A first resistive element is included in a starting circuit for the lamp and a second resistive element is in series with the arc tube during lamp operation for flicker elimination. The integral thick film resistor facilitates mounting and connection of the resistor elements within the lamp envelope. Favorably, the resistor substrate has a surface emissivity of greater than about 0.5, and preferably greater than about 0.9, to provide sufficient radiation cooling within an evacuated outer lamp envelope to prevent resistor failure while keeping the size of the resistor small enough for use as a component in an HID lamp. Additionally, a suitable coating of low vapor pressure thickness covers the solder connecting the metallic resistor terminals to the substrate to prevent evaporation of the solder and its deposition on the inner surface of the outer lamp envelope.

Abstract: A lamp assembly includes a tubular incandescent lamp located between the four tube sections of a double twin tube compact fluorescent lamp such that heat is transferred from the incandescent lamp to the fluorescent lamp when the incandescent lamp is energized. A power source provides power to the incandescent lamp and to the fluorescent lamp through a thermal switch. The thermal switch is in thermal contact with the incandescent lamp and the fluorescent lamp. When the lamp assembly is turned on, the switch applies power to the incandescent lamp initially. When the switch is heated by the incandescent lamp to a predetermined temperature, the switch deenergizes the incandescent lamp and applies power to the fluorescent lamp.

Abstract: An arc discharge lamp having an arc tube mounted within a lamp envelope includes a thermal switch for controlling application of electrical energy to a starting electrode. The thermal switch is mounted between the arc tube and the lamp base with its longitudinal axis generally parallel to the central axis of the lamp envelope. The thermal switch is spaced from the central axis of the lamp envelope by a support rod and extends into an annular space between the lamp stem and the wall of the lamp envelope. As a result, the maximum temperature of the thermal switch during lamp operation does not exceed about 400.degree. C.

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 high pressure lamp assembly having an improved structure for supporting the discharge tube while providing an opening bi-metallic switch for electrically disconnecting the auxiliary electrode. Metallic frames are disposed at the upper and lower ends of the discharge lamp to provide at least partial support to the discharge tube. A non-conductive bridge assembly is connected between the lead through of the auxiliary electrode and a conductive rod extending from the stem. The non-conductive bridge provides at least partial mechanical support to the discharge tube. Connected across the non-conductive bridge is the starting resistor and bi-metallic switch element. When the bi-metallic element is unheated, it provides electrical connection through the starting resistor to the auxiliary electrode. When heated by the heat from the discharge tube, the bi-metallic switch moves out of engagement with the ceramic bridge and thus breaks the electrical connection to the auxiliary electrode.

Abstract: A glow discharge lamp includes a sealed lamp envelope containing a noble gas and mercury, a cathode and an anode disposed in the lamp envelope and an incandescent filament for emitting visible light for illumination immediately upon application of power and for emitting little or no visible light after a glow discharge is formed between the cathode and the anode. The filament, the cathode and the anode are electrically connected in series. The lamp envelope typically includes a phosphor coating for emission of visible light upon absorption of ultraviolet radiation from the glow discharge. An optional switch can be used for disconnecting the filament during steady state operation of the glow discharge lamp.

Abstract: An electric discharge lamp is disclosed utilizing an improved thermally responsive switch for operation of an auxiliary starting electrode. The improved switch has a more compact structural configuration which further accommodates temperature excursions beyond the design closure temperature without exceeding elastic limits of the metals employed in the switch construction. A metal halide lamp of relatively compact construction which employs the improved switch is also disclosed.

Abstract: A high-pressure sodium vapor discharge lamp having a discharge vessel in which main electrodes are arranged and an ignition system which comprises an electric conductor surrounding the discharge vessel over at least a part of its circumference, which conductor is electrically connected to a main electrode at least in the inoperative state of the lamp. The electric conductor is a clamping member clamping around the discharge vessel. A fixed, arcuate positioning of the electric conductor is thus obtained.

Abstract: An HPS sodium vapor discharge lamp having a starting aid consisting essentially of a metallic band disposed circumscribing one end of the lamp discharge vessel, and means for applying a voltage to the metallic bond for inducing ionization throughout the volume of the discharge vessel to facilitate lamp starting. The metallic band may define a heat shield for inhibiting thermal radiation from one end of the discharge vessel.

Abstract: In parallel connecting a starter to a luminous tube, the starter being formed by a coiled nonfusible metal wire which is wound to or laid along the outer wall of the luminous tube and a nonlinear capacitor which is in series connected to the nonfusible metal wire. As a result of this, the discharge lamp can be assuredly and stably lit with a small size ballast. Furthermore, pass of large current through the starter can be prevented even if the luminous tube is leaked. Furthermore, if the vacuum outer bulb is leaked or broken, the circuit of the starter can be opened by melting the nonfusible metal wire.

Abstract: A high pressure metal vapor discharge lamp comprises a light-emitting tube in which a pair of electrodes is enclosed, a starting element including a normally closed-type thermal switch and a resistive member, the starting element generating a pulse by closing and opening switch operations, a connecting element for electrically connecting the starting element to the electrodes, the pulse being applied to the electrodes through the connecting element, and a member including an insulating body provided in vicinity of the thermal switch for causing a conductive portion to be formed on the body, the conductive portion being sufficient to bypass a current supplied to the starting element by repetitions of the switch operations, thereby lowering the pulse voltage.

Abstract: A metal vapor discharge lamp has a burner for sealing xenon gas, mercury and a light-emitting additive in a translucent ceramic tube, a starting device of a thermal switch type which has a series circuit of a thermal switch and a coil filament and which is connected in parallel with the burner, and an outer envelope for sealing the burner and the starting device therein. In the lamp, the following inequalities must be satisfied:13.3.ltoreq.P.multidot.(B/A).ltoreq.6650.05.ltoreq.d.ltoreq.0.122,200.ltoreq.T.ltoreq.2,800where A is the volume (cm.sup.3) of the outer envelope, B is the volume (cm.sup.3) of the burner, P is a gas pressure (Pa) at room temperature of xenon sealed in the burner, d is a diameter (mm) of the coil filament, and T is a temperature (K) of the coil filament during operation.

Abstract: A high vacuum sodium vapor lamp whose discharge tube is surrounded by a heating coil connected in series with a switch opening to interrupt the heating after the lapse of a heating period sufficient to allow breakdown of the tube, is also provided with overvoltage protection and especially an element located in the lamp base, for limiting the autoinductive voltage poles to a level sufficient for breakdown of the tube but insufficient to allow breakdown between the terminals of the lamp.

Abstract: A starter circuit for metal halide discharge lamps in which a pair of spiral line generators are coupled between the source of lamp operating power and the electrodes of the high intensity discharge lamp. The spiral line generators are connected across the electrodes, in accordance with the invention, in a manner such that the high voltage short duration pulses from the spiral line generators are substantially additive across the discharge lamp electrodes, thus, in effect, substantially doubling the breakdown voltage available across the discharge lamp electrodes.

Abstract: A lamp having a ceramic molding between a cap and a lamp envelope, the current supply conductors passing through the molding between the cap and the envelope. The conductors pass through separate ducts in the molding, one of the conductors includes a fuse accommodated entirely within the duct, and that duct is sealed at an end adjacent the lamp cap by a coherent mass of material such as a base cement. Flashover from a fuse arc to either the other conductor or the lamp cap is prevented.

Abstract: In a high pressure discharge lamp device provided with an inductive stabilizer and a starting circuit consisting of a serial circuit of a resistor and a bimetal switch, a pulse waveform conversion circuit is arranged therein to reduce the pulse peak of the starting voltage and also broaden the pulse width of the starting voltage. The pulse waveform conversion circuit comprises a serial circuit of a resistor and a switching element, such as micro-gap element, which operates at a voltage lower than the starting voltage of the discharge lamp but higher than the secondary load-free voltage of the stabilizer.

Abstract: A lighting system having a high pressure gas discharge light source and an incandescent light source within a common sealed and evacuated bulb. A ballast unit fitted externally to the neck of the bulb includes in series with the incandescent light source an interrupter element and control circuitry therefor, and a choke coil in series with the gas discharge light source.The control circuitry represents an equivalence logic with two variables, wherein the output terminal of an equivalence circuit is connected to the control input of the interrupter element while its input terminal is connected to a voltage divider system connected across the gas discharge light source. The output terminal is energized only if either both or neither of the input terminals of the equivalence circuit are energized. The interrupter element is closed when the output terminal of the equivalence circuit is energized.

Abstract: The invention relates to a high-pressure sodium vapor discharge lamp comprising a discharge vessel and a glow starter. The glow starter in the inoperative condition of the lamp is electrically connected parallel to the discharge vessel. In the operative condition the glow starter is switched off electrically by means of a bimetal switch. According to the invention the contact point of the bimetal switch which is connected to the glow starter is situated on the wall of the discharge vessel. Herewith a reliable and simply realizable positioning of the contact point is obtained.

Abstract: In a metal vapor discharge lamp for operating it by high voltage generated in the actuation of a heat sensitive switch means in an outer bulb, a relatively low pressure of a sealed gas or mercury is sealed in the outer bulb to operate the heat sensitive switch means in the gas atmosphere to control the surge voltage to a desired degree whereby the discharge lamp is operated without failure and the insulation breakdown of a ballast and an operation circuit is prevented.

Abstract: An electrical conductor device is connected between an anode voltage supply terminal on the funnel and an electron gun assembly in the neck in parallel with a conductive inner graphite film for electrical connection of the terminal and the assembly. The conductive inner graphite film has a high-resistance portion and a low-resistance portion, and the electrical conductor device has a smaller resistance than that of the high-resistance portion. Upon spot knocking, high voltage is selectively supplied to the electron gun assembly through the electrical conductor device and in operation, through the conductive inner graphite film.

Abstract: An improved high pressure sodium vapor lamp is described having resistance heater means contained within a tubular light-transmitting ceramic envelope that further contains a reservoir of sodium-mercury amalgam in excess of the quantity vaporized during lamp operation and which are supplied by electric current other than the lamp current responsive to a rise in the lamp operating voltage to reduce the quantity of amalgam being vaporized during lamp operation to help maintain said lamp operation at a relatively constant voltage. In a preferred embodiment, said resistance heater means comprises a refractory metal coil wound around the tungsten shank at one thermionic electrode and electrically insulated therefrom, with said thermionic electrode including a tubular metal inlead serving as the amalgam reservoir, and with the electric current being supplied at a lower value to said refractory metal coil than being supplied to said thermionic electrode.

Abstract: An improved high pressure sodium vapor lamp is described having resistance heater means contained within a tubular light-transmitting ceramic envelope that further contains a reservoir of sodium-mercury amalgam in excess of the quantity vaporized during lamp operation in order to increase the quantity of amalgam being vaporized during lamp operation and thereby help maintain the desired lamp color temperature. In a preferred embodiment, said resistance heater means comprises a refractory metal coil wound around the tungsten shank of one thermionic electrode and electrically insulated therefrom with said thermionic electrode including a tubular metal inlead serving as the amalgam reservoir.

Abstract: An improved high pressure sodium vapor lamp is described having resistance heater means contained within a tubular light-transmitting ceramic envelope that further contains a reservoir of sodium-mercury amalgam in excess of the quantity vaporized during lamp operation in order to heat the ceramic envelope before lamp starting and thereby reduce the starting voltage requirements. In the preferred embodiment, said resistance heater means comprises a refractory metal coil wound around the tungsten shank of one thermionic electrode and electrically insulated therefrom and which is supplied with lower current than is subsequently applied to said electrodes for the lamp operation.

Abstract: A high-pressure discharge lamp has a starting circuit consisting of a bimetallic switch and a resistor, which is connected in parallel with the arc tube, and is turned on via a mercury lamp ballast. The current which flows into the starting circuit is limited by the current that flows into the arc tube and by the output of the ballast. Therefore, the extinguishing voltage phenomenon that hitherto had developed immediately after the lamp was turned on no longer takes place.

Abstract: A high pressure metal vapor discharge lamp comprising a discharge tube disposed in an outer jacket; said discharge tube having electrodes and containing a filling comprising a starting rare gas composed primarily of xenon at a pressure from 40 to 200 Torr; means for starting said discharge tube comprising a glow starter comprising a pair of contacts spaced apart not more than 2.5 mm from each other, and containing a gas composed primarily of argon at a pressure of at least 7 Torr; the pressure in said glow starter (P.sub.g) being related to the pressure in the discharge tube (P.sub.i), according to the expression ##EQU1## and a starting electric conductor adapted to contact the discharge tube on starting thereof and to separate from the discharge tube after starting.

Abstract: Apparatus for starting and operating a discharge lamp includes a starter device having a normally-closed (N/C) switch including a pair of contacts each connected to a bimetal with the bimetals having opposite flexure deviations. Circuitry is provided for coupling one bimetal to a ballast and also to a discharge lamp whereby short-circuit current flows through both bimetals to open the switch and initiate conductivity of a discharge lamp and through one bimetal to maintain the switch operational and continue lamp conductivity.

Abstract: A high intensity discharge lamp having a hermetically sealed envelope with support wires therethrough has an arc tube therein with support wires whereby a starter device having first and second contacts of a normally-closed switch has a first bimetal coupling the first contact to one support wire and a second bimetal coupling a second contact to another support wire with the bimetals positioned to flex in opposite directions and enhance the operation of the contacts and of the high intensity discharge lamp.

Abstract: An electric arc lamp in combination with an electronically controlled incandescent filament to provide auxiliary illumination during warm-up and hot restart of the arc lamp, the filament control circuit being responsive to the arc lamp voltage and current and operative in three modes, full off, full on, and switching on and off the latter so as to allow capacitive and inductive coupling of energy into the arc lamp for the purpose of starting it and bringing it into the arc mode of operation.

Abstract: The invention relates to a glow-discharge starter (10) having a bimetallic electrode (11) and a rare gas.According to the invention the glow-discharge starter also comprises a reversible getter (13) which, when the temperature increases, gives off a gas and, when the temperature decreases, absorbs the gas and the value of the gas pressure also determines the electric conductivity of the glow-discharge starter.A glow-discharge starter is thereby obtained in which undesired breakdown of the glow-discharge starter can be prevented by controlling the gettering temperature.

Abstract: A circuit for starting and operating a low wattage high intensity discharge lamp from a source of AC line voltage. The circuit includes a glow starter device having a first terminal connected to a first bimetal, a second terminal connected to a second bimetal, and third terminal connected to a rigid conductive member, the bimetals being electrically connected together at one end which makes a normally closed contact with the rigid member in the quiescent state of the device. A choke coil and a capacitor are series connected in that order between one of the AC input terminals and the second terminal of the starter device, and a second AC input terminal is connected to the third terminal of the starter. The first and third terminals of the starter device are connected across the discharge lamp terminals.

Abstract: A low wattage high intensity discharge lamp having a quartz arc tube and a glow starter disposed within a bulbous glass envelope containing an inert gas, such as argon, at subatmospheric pressure. The starter within the envelope comprises a first bimetal connected to one of the arc tube lead-in wires, a second bimetal connected to one end of a conductive support wire sealed through the bulbous envelope, and a fixed first contact attached to another conductive support wire sealed through the bulbous envelope and also connected to the other lead-in wire of the arc tube. The bimetals are electrically connected together at one end which makes a normally closed contact with the fixed contact in the quiescent state of the starter.

Abstract: A high pressure metal vapor discharge lamp according to the present invention comprises the following first and second starting aid circuits mounted within an outer envelope. The first starting aid circuit includes a starting aid and a first thermal switch, and the second starting aid circuit includes a resistive element and a second thermal switch. These two thermal switches are arranged so that at the time of re-starting after a certain period of stopping, the first thermal switch is reset earlier than the second thermal switch. In this high pressure metal vapor discharge lamp having this specific structure, the starting characteristic is improved, and a high voltage pulse generated by the second starting aid circuit and a ballast is assuredly absorbed by an arc tube and occurrence of dielectric breakdown in the respective elements can be completely prevented.

Abstract: A glow bottle starter having three lead-in wires and containing two bimetals connected together at one end and a rigid tungsten rod. The bimetals make normally closed contact with the tungsten rod in the quiescent state of the starter, and upon electrical current flow through one or both of the bimetals to cause elevation to a predetermined temperature, the bimetals are operative to separate from the tungsten rod. In a circuit including the glow-bottle starter for starting a discharge lamp, one of the bimetals and the rigid tungsten rod are connected across the output of a ballast circuit, and the tungsten rod and other bimetal are connected across the lamp.

Abstract: The invention relates to a discharge lamp which has a discharge vessel provided with an external auxiliary electrode. The lamp also has a bimetal which in the inoperative condition of the lamp causes the external auxiliary electrode to bear against the discharge vessel. According to the invention the auxiliary electrode is connected to an end of only one bimetallic strip and in the operating condition of the lamp the auxiliary electrode is remote for the greater part from the discharge vessel due to the action of the bimetal. Combined with an operating condition of the lamp in which no hindrance is experienced from the auxiliary electrode.

Abstract: A high pressure sodium lamp, which includes a discharge tube enclosing xenon at pressures in excess of 300 torr, is reliably started by the combination of an igniter, a conductor wrapped around the discharge tube, and a switching circuit. The igniter provides periodic pulses of 2500 to 4000 volts with a duration of at least one microsecond. The switching circuit provides a high voltage pulse having an amplitude about equal to the amplitude of the periodic pulses and a duration much greater than the duration of the periodic pulses. The conductor intensifies the electric field within the discharge tube. A conventional lamp ballast provides ac power during starting and normal operation.

Abstract: Method and apparatus for starting high intensity discharge lamps utilizing a spiral line pulse generator to generate high voltage, short duration starting pulses. The spiral line pulse generator includes two conductors and two insulators, each in the form of an elongated sheet, in an alternating arrangement which is rolled together in a spiral configuration having a plurality of turns. A high voltage, short duration pulse is provided upon closure of a low inductance switch coupled between the conductors. The pulse is coupled to the discharge lamp by an elongated conductor located in close proximity to the discharge tube. The spiral line pulse generator can be included within the outer jacket of the light source.

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 high pressure sodium vapor discharge lamp,characterized in thatits discharge tube contains xenon gas at a high pressure of e.g. over 150 torr, at least one of discharge electrodes has a projection conductor which is disposed extending therefrom towards an inside surface of a side wall of a tube envelope of the discharge tube in a manner that outer end of the projection conductor is disposed in proximity to a side wall of said tube envelope with a predetermined gap in-between anda starting aid conductor is disposed lengthwise on the outside surface of the side wall, and connected to the other electrode.

Abstract: Disclosed is an arc discharge lamp starting device which comprises a starting aid circuit connected in parallel to an arc tube and disposed within an outer envelope. This starting aid circuit comprises a thermal switch, a heater and a resistor. This thermal switch includes contact rods having a high melting point and a small work function and a bimetal plate.In this arc discharge lamp starting device, since the time of duration of the chattering phenomenon caused between the contact rods is very long, the arc discharge lamp can be started assuredly by this starting device.

Abstract: An HID lamp has a very positive acting and simple resilient safety switch positioned proximate the inner surface of the bulb portion of the protective outer envelope and in contact therewith which maintains the switch in a closed position. When the envelope is shattered, the closed switch will open to break the electrical path to the arc tube, thereby rendering the lamp inoperative.

Abstract: A mechanical safety switch for high intensity discharge lamps designed to open and remove the current from the arc tube to extinguish the discharge when the lamp envelope is broken in which a leaf spring switch arrangement is used comprising two leaf spring members which are in contact along a substantial portion of their lengths to thereby reduce the current carrying requirement per unit area of the leaf springs.