Abstract: A lighting system waveform shaping circuit (WSC) includes a line voltage input, a line voltage output connectable to an input voltage port of a control unit, a neutral line input connectable to a neutral line of a voltage power source, and the WSC including an impedance matching network (IMN) configured to alter an input impedance of the lighting control circuit. In one embodiment, the IMN can include a resistor in series with the line voltage input, and an actively-controlled bypass switch in parallel with the resistor. In another embodiment, the IMN can include respective ferrite chokes surrounding the input and the output voltage lines, a capacitor between the line voltage input and the neutral line input, a capacitor between the neutral line input and a protected earth ground, and a resistor in series between the neutral line input and the lighting control unit neutral line input port.

Abstract: In at least one embodiment, an electronic system and method includes a controller to control a switching power converter in at least two different modes of operation depending on whether the controller detects a dimmer or not and/or whether a load requests more power than either of the two operational modes can provide. In at least one embodiment, the controller detects whether a dimmer is phase cutting an input voltage to a switching power converter. The controller operates the switching power converter in a first mode if the dimmer is detected, and the controller operates the switching power converter in a second mode if the dimmer is not detected. The controller also transitions between operating the switching power converter in the first mode and the second mode if a status of detection of the dimmer changes.

Abstract: A circuit to power an electron source includes a filament transformer comprising a primary side and a secondary side, a high-voltage transformer coupled to the filament transformer and the electron source, and an alternating current (AC) current limiter coupled in series with the primary side or the secondary side of the filament transformer. The AC current limiter includes a diode bridge and a current-limiting device in the diode bridge.

Abstract: A cathodoluminescent lighting system has a light emitting device having an envelope with a transparent face, a cathode for emitting electrons, an anode with a phosphor layer and a conductor layer. The phosphor layer emits light through the transparent face of the envelope. The system also has a power supply for providing at least five thousand volts of power to the light emitting device, and the electrons transiting from cathode to anode are essentially unfocused. Additional embodiments responsive to triac-type dimmers with intensity and color-changes in response to dimmer control. A power-factor-corrected embodiment is also disclosed.

Abstract: A cathodoluminescent lighting system has a light emitting device having an envelope with a transparent face, a cathode for emitting electrons, an anode with a phosphor layer and a conductor layer. The phosphor layer emits light through the transparent face of the envelope. The system also has a power supply for providing at least five thousand volts of power to the light emitting device, and the electrons transiting from cathode to anode are essentially unfocused. Additional embodiments responsive to triac-type dimmers with intensity and color-changes in response to dimmer control. A power-factor-corrected embodiment is also disclosed.

Abstract: A cathodoluminescent lighting system has a light emitting device having an envelope with a transparent face, a cathode for emitting electrons, an anode with a phosphor layer and a conductor layer. The phosphor layer emits light through the transparent face of the envelope. The system also has a power supply for providing at least five thousand volts of power to the light emitting device, and the electrons transiting from cathode to anode are essentially unfocused. Additional embodiments responsive to triac-type dimmers with intensity and color-changes in response to dimmer control. A power-factor-corrected embodiment is also disclosed.

Abstract: The method according to the present invention relates to controlling a gas discharge lamp during a pre-heating period of said lamp, wherein a first terminal of a control circuit is connected with a first electrode of the lamp and a second terminal of a control circuit is connected with a second electrode of the lamp, and wherein means are provided, suitable for connecting the first terminal and the second terminal with each other, thus providing a conducting path, and suitable for disconnecting the first terminal and the second terminal. Furthermore the method comprises the use of a chargeable and dischargeable power buffer, for powering control circuitry for operating the switching means.

Abstract: A cathodolumineseent lighting system has a light emitting device having an envelope with a transparent face, a cathode for emitting electrons, an anode with a phosphor layer and a conductor layer. The phosphor layer emits light through the transparent face of the envelope. The system also has a power supply for providing at least five thousand volts of power to the light emitting device, and the electrons transiting from cathode to anode are essentially unfocused. Additional embodiments responsive to triac-type dimmers with intensity and color-changes in response to dimmer control. A power-factor-corrected embodiment is also disclosed.

Abstract: A lamp driving device includes a switch circuit for supplying a signal; a transformer which boosts a voltage of the signal from the switch circuit and supplies the boosted voltage to at least one lamp; a safety circuit which compares a threshold value with at least one of the boosted voltage and a current through the lamp, and intercepts at least one of the boosted voltage and the current through the lamp in accordance with the comparison result; and a warming part for warming the lamp in an early stage with a voltage less than or equal to the threshold value.

Abstract: A germicidal UV reactor for use in fluid purifiers is provided, in which the UV reactor comprises an UV lamp with an UV transparent primary envelope and also an UV transparent secondary envelope around the primary envelope. The outer surface of the secondary envelope is in contact with a flowing fluid to be purified. There is an isolating space between the outer surface of the primary envelope and the inner surface of the secondary envelope. At least one of the outer surface of the primary envelope and the inner surface of the secondary envelope is provided with electrical means for heating and thus enhancing UV emitting efficiency of the UV lamp.

Abstract: A reliable and efficient circuit for lighting a discharge lamp is described. An inverter accepts a direct current supply voltage and outputs an alternating current lamp voltage to drive the discharge lamp at a relatively high frequency. In one embodiment, the inverter includes semiconductor switches in a full-bridge configuration, a transformer feedback circuit to control the semiconductor switches, and a series L-C resonant circuit. In one embodiment, the inverter includes semiconductor switches in a half-bridge configuration, a transformer feedback circuit to control the semiconductor switches, and a series L-C resonant circuit. The inverter can drive multiple discharge lamps in a parallel configuration. A bypass circuit can also be coupled across a cathode of the discharge lamp to extend the life of the discharge lamp. The bypass circuit activates when a lamp cathode wears out.

Abstract: A phase random access memory including a plurality of access transistors, each access transistor including a drain region, and a phase-changeable film shared by the plurality of access transistors. The phase-changeable film is connected to a bitline through a first electrode and connected to each respective drain region through at least one of a plurality of second electrodes.

Abstract: A UV lamp unit is provided and comprises a lamp in the form of a mercury low pressure amalgam lamp that is provided with at least one amalgam deposit. A cladding tube surrounds the lamp in such a way that an air gap is provided between the lamp and the cladding tube. An element is provided in one axial direction of the lamp, in the region of the at least one amalgam deposit, for influencing the temperature of the amalgam.

Abstract: An Analog-to-Digital (A/D) converter includes signal paths that are responsive to an analog input signal, to generate a multi-bit digital signal. A respective signal path includes a comparator. A synchronizing circuit is responsive to a clock signal and outputs of the comparators, to generate a respective delayed clock signal that is applied to a respective comparator. A respective signal path also includes a respective decoder that is responsive to a respective comparator and to the clock signal.

Abstract: In a phase-change nonvolatile storage device using a phase-change material as storage cells, which is improved to overcome a basic problem involved in conventional devices of this type and reliably, easily operable as a storage device, the pre-record state of a storage cell is read before recording information in the storage cell, and a write pulse optimum for transition is selected and applied. If the storage cell need not change in phase, the write pulse need not be applied. Alternatively, the pulse is adjusted in waveform of the trailing edge, depending on whether the storage cell should be changed to the amorphous state or the crystal state, to control the crystallization hold time.

Abstract: An electronic starter for fluorescent lamp has a preheating circuit for controlling the preheating of the fluorescent tube and a power switch and locking circuit for cutting off the current to the preheating circuit. The power switch and locking circuit makes use of the voltage level on the power input to determine the status of the fluorescent tube. A high voltage on the power input represents that the fluorescent tube has failed to turn on in the ignition operation, whereby the power switch and locking circuit thereupon cuts off the current to the preheat circuit, thereby eliminating flickering of the fluorescent tube and so preventing irritation to the eyes, and extending the service life of the lamp.

Abstract: Provided is a lighting circuit (10, 100, 160) which includes a line voltage source 12 used to supply a full wave signal 72 to circuit 10. A ballast 14 is connected to the line voltage source 12, and a lamp 16. Further included in the circuit (10, 100, 160) is an electronic starter (18, 102, 159) which is connected across the lamp 16. Electronic starter (18, 102, 159) includes a pulse generating circuit ((60, 62, 64) (108, 110, 112, 152, 154)), a switch (30, 120) which is connected to provide a cathode current pulse 74 to first and second cathodes (22, 26) of the lamp 16, generated by the pulse generating circuit. The pulse generating circuit and switch operate in such a manner that the pulse generating circuit limits the duration of the cathode current pulse 74 which is delivered to cathodes 22 and 26. A feedback or pulse timeout circuit (116, 118, 120, 121, 128, 130) may also be used to sense a current delivered to cathodes 122, 126 by cathode current pulse 74.

Abstract: Method for detecting the rectification effect in at least one gas discharge lamp (10) and electronic ballast for operating at least one gas discharge lamp, which recognises the appearance of the rectification effect in the gas discharge lamp (10). In order to be able to detect the appearance of the rectification effect in the gas discharge lamp (10) simply and with high sensitivity there is monitored the current (i.sub.1) flowing via a primary winding (7A), connected parallel to the gas discharge lamp (10), of a heating transformer (7A-C) or a parameter (i.sub.2, u.sub.3) dependent upon this current (i.sub.1) , and in the event that a predetermined limit value is overshot the presence of the rectification effect in the gas discharge lamp (10) is determined.

Abstract: A compact fluorescent lamp system includes a housing. An external base connector is mounted in the housing. The external base connector receives electrical power from an external source. A ballast unit is secured within the housing and electrically connected to the external base connector. The ballast unit controls the electrical power received from the external source. The compact fluorescent lamp system also includes a lamp unit. The lamp unit includes an amalgam ball pellet within the lamp unit, first and second lamp electrodes extending into the lamp unit, and a gas which breaks-down, permitting an electrical current to pass through the lamp unit. An inside wall of the lamp unit is coated with a material which fluoresces when the gas within the sealed lamp unit ionizes. The lamp unit also includes an extended wire connection having a first end electrically connected to one of the first and second lamp electrodes and a second end located near another point on the lamp unit.

Abstract: A method and apparatus for signaling promotional operation of a gaming device using existing fluorescent illumination lamps. An illumination lamp on a gaming device is operated continuously during normal operation, then flashed to signal promotional operation. Alternatively, an illumination lamp can be dimmed during normal operation, then operated at full brightness during promotional operation. To achieve flashing and dimming operation, a conventional starter is removed from a socket in a fluorescent lamp fixture and replaced with a controllable starter that fits into the same socket. The starter has a pair of wire leads for receiving a control signal for flashing or dimming the lamp. The controllable starter includes a starter circuit having a switch connected between two power terminals of the starter. When the switch closes responsive to the control signal, it shorts circuits the lamp, thereby extinguishing the arc and allowing preheat current to flow in the heating filaments of the lamp.

Abstract: An amplifying-gate thyristor having an increased integrated circuit includes a main thyristor and an amplifying thyristor. The amplifying thyristor is of the gate turnoff-type. The main thyristor and the amplifying thyristor are such that the amplifying thyristor remains in the conductive state while the main thyristor is conductive. A control circuit turns off the amplifying thyristor when the current through the main thyristor is approximately its hold current.

Abstract: A fluorescent lamp flashing circuit is comprised of a fluorescent lamp to which an alternating supply voltage source is connected through a series connected loading reactance device which provides current limiting. The heaters of the fluorescent lamp are independently fed. A switching device disconnects and reconnects the alternating supply voltage at a predetermined frequency rate which is determined by a control circuit which controls a switching device. When the switching device is closed, the fluorescent lamp is bypassed through a full wave rectifier bridge and the reactance device is connected in parallel with the supply voltage source and with a bleeding resistance to load the bridge and to form a resonant circuit to maintain the loading reactance device constant and permitting an energy exchange between the supply voltage source and the loading reactance device in a resonant mode thereby maintaining a sine wave form and minimizing loss.

Abstract: A method and apparatus for signaling promotional operation of a gaming device using existing fluorescent illumination lamps. An illumination lamp on a gaming device is operated continuously during normal operation, then flashed to signal promotional operation. Alternatively, an illumination lamp can be dimmed during normal operation, then operated at full brightness during promotional operation. To achieve flashing and dimming operation, a conventional starter is removed from a socket in a fluorescent lamp fixture and replaced with a controllable starter that fits into the same socket. The starter has a pair of wire leads for receiving a control signal for flashing or dimming the lamp. The controllable starter includes a starter circuit having a switch connected between two power terminals of the starter. When the switch closes responsive to the control signal, it shorts circuits the lamp, thereby extinguishing the arc and allowing preheat current to flow in the heating filaments of the lamp.

Abstract: A starter unit for a fluorescent tube includes in parallel across two terminals, first and second main thyristors head-to-tail connected and a zener protection diode. The gate of the first thyristor is connected to one of the terminals through a resistor and to the other terminal through the series connection of an auxiliary thyristor with a zener diode (Z). The gate of the auxiliary thyristor is connected to a control terminal of the integrated circuit. The cathode of the auxiliary thyristor is connected with a supply terminal of the integrated circuit and to a storing capacitor. The gate of the second thyristor is connected to a control terminal of the integrated circuit.

Abstract: The cathodes of a fluorescent lamp are preheating and the medium between the cathodes is ignited into a plasma by heating the cathodes for a predetermined warm-up time period by conducting current from a supply power source through the cathodes for a conductive time interval, and applying a relatively high voltage starting pulse to the cathodes at the end of the conductive time interval or alternatively suppressing the high voltage starting pulse during the predetermined warm-up time period. Suppressing the high voltage starting pulse during the warm-up time period, thereby preventing erosion the thermionic coating of the cathodes due to positive ion bombardment. A controllable semiconductor switch is connected to the cathodes to control the current flow through them. The high voltage starting pulse is derived from commutating the semiconductor switch into a nonconductive state when the applied current level drops to the characteristic holding current value of the switch.

Abstract: A circuit for use in providing high voltage power to a neon bulb positioned on the vehicle utilizing the vehicle DC battery as the power source. The circuit includes an invertor, a transformer, and a rectifier. The invertor receives low voltage DC from the vehicle battery, converts the low voltage DC to a low voltage AC drive voltage, and delivers the AC drive voltage to the transformer primary for conversion to a high voltage AC at the transformer secondary. The rectifier receives the high voltage AC from the transformer secondary, converts the high voltage AC to high voltage DC, and delivers the high voltage DC to the neon bulb. Since the power delivered to the neon tube is DC there is less need to shield the tube with respect to electro magnetic emissions and parasitic losses in the wire runs between the battery and the neon tube are significantly reduced.

Abstract: An electronic starter for a fluorescent lamp comprises a power switch, controlled at its gate by a gate-control circuit and an auxiliary supply circuit that gives the necessary logic supply voltage to the gate-control circuit on a terminal of a capacitor. The gate-control circuit comprises a comparator with two voltage references to measure a duration of preheating of the lamp, the input of this comparator receiving the logic voltage given by the capacitor, the output of the comparator being used to command the closing or the opening of the switch. In one improvement, there is provided a preheating current measurement circuit to detect the optimum current for lighting up the lamp once the necessary preheating time has elapsed.

Abstract: A circuit for protecting fluorescent lamps connected to high frequency electronic ballasts has a detecting bridge connected to the fluorescent lamps, an output of the detecting bridge varying linearly with the highest voltage across the fluorescent lamps, a number of shunt capacitors equal to the number of fluorescent lamps, each shunt capacitor being connected between the detecting bridge and a corresponding fluorescent lamp, a timer connected to the detecting bridge output, a trigger connected to an output of the timer, the trigger being responsive to an over-voltage condition of a fluorescent lamp operating at failure mode, and a controllable switch connected across the fluorescent lamps, the controllable switch being controlled by an output of the trigger. The controllable switch, when closed, couples the shunt capacitors across the terminals of a corresponding fluorescent lamp and shuts down the fluorescent lamp which is operating at failure mode or at the end of its operating life.

Abstract: A new fluorescent device including an electronic fluorescent starter, a phase leading capacitor, a ballast, a bridge rectifier, a fluorescent lamp, a brightness compensation circuit, and a control circuit, the electronic fluorescent starter consisting of a master switch circuit, an ignition circuit and a time control circuit, wherein the electronic fluorescent starter matches with the ballast to turn on the fluorescent lamp; the control circuit turns the electronic fluorescent starter to the open circuit state when the fluorescent lamp is turned on; the brightness compensation circuit improves the intensity of light from the fluorescent lamp.

Abstract: An improved fluorescent light ballast circuit extends the on/off life of a florescent lamp within a lighting circuit having a pair of series connected fluorescent lamps. The ballast circuit includes a DC pulse generation circuit, filtering and voltage regulation circuitry, a step-up voltage transformer, and a current altering circuit which alters the current within selected filaments within the lamps. The current altering circuit includes a diode and a coil winding which connect across a filament within one of the fluorescent lamps. The net effect of the current altering circuit is to increase the voltage supplied across the lamp connected to the current altering circuit so that the voltage levels across both lamps are balanced.

Abstract: For preserving and, thus, for extending the useful life of a picture tube of a picture tube screen device having a waiting state function. The filament current of the picture tube in the waiting state of the picture tube screen device is reduced by at least a slight percentage of an original filament current. Also, the picture tube is supplied with another video signal, in addition to an original video signal, that generates a beam current in the picture tube having a white image level that is at least a slight percentage of an original white image level generated by the original video signal.

Abstract: The present invention relates to a gas discharge lamp lighting system in which a voltage source is provided for supplying an a.c. voltage across the lamp electrodes and, further, a source of stored d.c. voltage which is gated to the electrodes in synchronism with and additive to the a.c. voltage, in order to provide a resultant voltage across the electrodes of a magnitude sufficient to light the lamp.

Abstract: In a circuit for operating a fluorescent lamp with controllable luminance, with the fluorescent lamp comprising a discharge path and heater coils, the discharge path is connected through a transformer to a controllable alternating current source. The current through the heater coils is preferably controllable in such fashion that the sum of the current through the discharge path and through the heater coils remains essentially constant.

Abstract: A ballast circuit for a fluorescent lamp including a magnetic choke electrically connected between the lamp and a power supply and an electronic starter circuit electrically coupled across said lamp, which ballast circuit is configured to provide a power factor of at least 90%. To this end, for certain lamps a power factor correcting capacitance is electrically connected across the power supply. For other lamps, a power factor correcting resistance is coupled between the ballasting capacitance and inductor so that the inductor and ballasting capacitance close to resonance.

Abstract: A fluorescent lamp system including a ballast with primary and secondary windings and a switch for each of the plurality of electrodes of the lamp system. Each switch is operable in response to the voltage across its associated lamp after its associated lamp turns on to interrupt the connection of an associated electrode to its associated heater winding, and wherein at least two of the plurality of switches conduct current which flows through a semiconductor conducting device before the lamps turn on.

Abstract: A fluorescent lamp system including a ballast with primary and secondary windings and a switch for each electrode of the lamp system. Each switch is operable in response to the voltage across its associated lamp after its associated lamp turns on to interrupt the connection of an associated electrode to its associated heater winding and wherein at least one of said heater windings is a portion of the secondary winding.

Abstract: A fluorescent lamp system including a switch for each electrode of the lamp system wherein each switch is operable in response to the voltage across its associated lamp after its associated lamp turns on to interrupt the connection of an associated electrode to its associated heater winding.

Abstract: An electric circuit for glow discharge lamp which regulates lamp output according to changing environmental conditions includes a power lamp circuit electrically connected between an anode lead-in wire and a cathode to create a lamp voltage, a filament power circuit electrically connected to a pair of cathode lamp filament lead-in wires to create a filament voltage whereby said lamp voltage decreases with an increasing filament voltage due to lamp characteristics, and a sensing and control circuit for adjusting the filament voltage in accordance with changing environmental conditions for maintaining lamp voltage at a predetermined constant value.

Abstract: A filament switch for a rapid start fluorescent lamp disconnects or reduces through phase modulation the heating current to a plurality of lamp filaments to save power. The switch uses a trigger in series with a voltage sensitive element and an impedance element, the switch being responsive to the difference between a lamp starting voltage and a lamp sustaining voltage for determining when and for how long the filaments are heated.

Abstract: A lighting device for a hot cathode fluorescent lamp used for a back light of a liquid crystal display or the like attempts to prolong the life of a lamp in a lighting device for a low consumption wattage fluorescent lamp. More specifically, the hot cathode fluorescent lamp is started while being pre-heated, and even after starting, a pre-heat current keeps flowing. The pre-heat current value after starting is set to be smaller than that at the time of starting for the purpose of optimizing the hot spot temperature. With employment of the configuration as described above, the lifetime of the hot cathode fluorescent lamp when used as a back light can extend to 10,000 hours or more.

Abstract: A circuit suitable for the instantaneous starting, continuation, and interruption of current through one or more gasfilled discharge tubes, in particular fluorescent lamps, is described. The circuit and lamp heaters are energized before instantaneous control can occur. One preferred silicon controlled rectifier (SCR) is used with a bridge rectifier. The SCR has the dual role of causing the capacitor to discharge through the pulse transformer, the secondary pulse voltage of which thereby causes the arc to strike immediately upon application of gate current, and then maintianing the lamp current as long as a supply of SCR gate current is provided. A second preferred control device, a TRIAC, is used without a bridge rectifier and again has a dual role of pulse-starting and maintaining current. This type of device is more conveniently arranged to provide for a dimming function as well. Applications include "flashing" advertising signs, general illumination, and signals.

Abstract: A charging method within a glass tube using a direct current of low voltage is provided in order to obtain a small fluorescent lamp with a light emission of high luminance. Two distinct discharges are achieved through use of one negative electrode. The filament-like negative electrode is arranged at a short spaced relation to a positive electrode at one end of the glass tube and upon application of the direct current voltage becomes the preliminary discharge. A second positive electrode is positioned at the opposite end of the glass tube and has a greater-spaced relation to the negative electrode resulting in the second discharge.

Abstract: An electronic starter for fluorescent lamps is disclosed. A Triac having a trigger electrode and having an anode and a cathode connectable to first and second filaments, respectively, of a fluorescent lamp is provided. A thermistor, a resistor, and a capacitor are connected in series across the anode and the cathode of the Triac, and a voltage responsive element, such as a bipolar Zener diode, is connected between the trigger electrode of the Triac and the junction between the resistor and the capacitor. This starter replaces conventional glow starters for fluorescent lamps, without requiring a special ballast.

Abstract: A negative glow fluorescent lamp includes a light-transmissive envelope enclosing a fill material which emits ultraviolet radiation upon excitation, a phosphor coating on an inner surface of the envelope, the phosphor coating emitting visible light upon absorption of ultraviolet radiation, a cathode located within the envelope for emitting electrons, first and second cathode leads extending through the envelope, an anode located in the envelope and spaced from the cathode for collecting electrons and first and second diodes coupled between opposite ends of the anode and the first and second cathode leads, respectively. The glow lamp can include one or more insulating discharge barriers which surround the cathode and block electron bombardment of the cathode during positive half cycles of the AC voltage. The discharge barriers are preferably as large in area as is practical and can be coated with an ultraviolet-reflecting material or with a phosphor layer.

Abstract: A discharge lamp apparatus is capable of securely detecting the decrease of emission in the terminal stage of the life of a discharge lamp by connecting a voltage detecting circuit to the discharge lamp, and a discharge lamp apparatus for securely starting, operating and dimming the discharge lamp, and is also capable of protecting the lamp in the event of abnormality; the apparatus includes two timer circuits, a reset circuit, a dimmer circuit, an abnormality detecting circuit, and a stopping circuit.

Abstract: A circuit for starting and operating fluorescent lamps from an a-c low frequency power source includes a reactive ballast means connected to ballast the lamps and having a non-linear characteristic for producing a plurality of harmonics of the power source frequency, and a capacitor and a cathode heating transformer connected in series and connected to receive power from said ballast means and resonant in a frequency range encompassing a plurality of said harmonics. This resonant voltage is applied across the lamps to aid the starting of their discharge and thereafter the lamps operate at the a-c power source frequency. The aforesaid resonance frequency range preferably is broad enough to encompass several harmonics of the power source frequency, for example the third through the ninth harmonics (180 to 540 Hz for a source frequency of 80 Hz). Preferably a switch is connected in series with the capacitor and cathode heating transformer for opening the cathode heating circuit when the lamps are operating.

Abstract: A rapid start fluorescent system which has its starting capacitance connected to a tap on the secondary of the ballast transformer which tap is located at a predetermined number of turns of the secondary.

Abstract: A starter circuit for a discharge lamp includes a current control circuit which initially has a low impedance so as to produce an initial cathode heating current for the lamp. The current control circuit is switched into a high impedance condition by means of a control voltage applied to its gate thereby causing a high voltage striking pulse to be applied across the lamp. A field effect transistor is effective to modify the control voltage to the gate such that the starting circuit is effective to produce a succession of starting pulses across the lamp during each half cycle of a rectified AC supply.

Abstract: A negative glow fluorescent lamp includes a light-transmissive envelope enclosing a fill material which emits ultraviolet radiation upon excitation, a phosphor coating on an inner surface of the envelope, the phosphor coating emitting visible light upon absorption of ultraviolet radiation, a cathode located within the envelope for emitting electrons, first and second cathode leads extending through the envelope, an anode located in the envelope and spaced from the cathode for collecting electrons and first and second diodes coupled between opposite ends of the anode and the first and second cathode leads, respectively. The glow lamp can include one or more insulating discharge barriers which surround the cathode and block electron bombardment of the cathode during positive half cycles of the AC voltage. The discharge barriers are preferably as large in area as is practical and can be coated with an ultraviolet-reflecting material or with a phosphor layer.

Abstract: A high frequency power circuit for energizing at least one gas discharge lamp with two filaments. The circuit is adapted to be supplied with power from a DC voltage source, and comprises semiconductor switching elements and control means for the semiconductor switching elements. The circuit also comprises a high frequency transformer having at least one primary winding which, in operation, is supplied with an AC voltage signal by the semiconductor switching elements. The transformer has at least one secondary main winding and secondary auxiliary windings. The secondary auxiliary windings, in operation, energize the filaments of the at least one gas discharge lamp. The control means are adapted to disconnect, in a stand-by mode, by at least one controllable switching means. The connection between the at least one secondary main winding and the at least one gas discharge lamp.