Abstract: A power control circuit for a projector for controlling a light source of the projector. The power control circuit includes: a detector for detecting an AC input voltage is a first value or a second value; a switch coupled to the detector, conducting or disconnecting of the switch being based on the detector detecting whether the AC input voltage is the first value or the second value, the switch further outputting a first control signal; and a laser driver coupled to the switch and the light source, in response the first control signal from the switch to change power consumption of the light source. When the AC input voltage is the first value, power consumption of the light source is a default value. When the AC input voltage is the second value, power consumption of the light source decreased from the default value.

Abstract: A self-adjusting power device for high efficiency electrical discharge machining and method thereof is disclosed. A high-voltage arc unit and a low-voltage discharge unit provide a high voltage arc pulse and a low voltage discharge pulse to an electrode respectively. The electrode machines a workpiece and feeds back a gap voltage to a discharge pulse generation unit. The discharge pulse generation unit determines whether the gap voltage is lower than a predetermined voltage or not. If yes, a discharge channel between the electrode and the workpiece is conducted, and the discharge pulse generation unit shuts down the high-voltage arc unit and the low-voltage discharge unit is still operating at ON time and shuts down at OFF time. If no, looping the determination of the discharge pulse generation unit. Therefore, discharge machining energy is accurately controlled and high efficient power saving is achieved.

Abstract: In a lighting apparatus containing a high pressure discharge lamp, an alternating current supplied to the discharge lamp at the time of steady lighting of the frequency (basic frequency) selected from a range between 60 and 1000 Hz and a low frequency having a frequency selected from a range between 5 and 200 Hz lower than the basic frequency is generated alternately. The frequency of the low frequency wave is changed in response to the change of the lighting voltage of the discharge lamp. The supply period of the basic frequency is increased and decreased little by little by every predetermined time.

Abstract: There is provided a coil component capable of minimizing mutual interference while disposing a plurality of coil parts in a single component. According to an embodiment of the present invention, the coil component includes: a bobbin part including two body parts disposed in parallel, the two body parts having coils wound therearound; and a core including two inner legs inserted into the body parts and two outer legs disposed outwardly of the body parts, the inner legs and the outer legs having the same cross sectional area.

Abstract: An adaptive sliding-frequency triggering ignition method for electronic ballast of high pressure gas discharge lamp includes the steps of: measuring an accurate value of free oscillation frequency of the ballast load loop by using a single-chip before sliding-frequency triggering ignition, implementing safe and reliable sliding-frequency triggering ignition after calculating the initial frequency and ending frequency of sliding-frequency triggering ignition according to the accurate value. The method can safely and reliably finish sliding-frequency triggering ignition course, thus improving the parameters such as the quality, life of the high pressure gas discharge lamp electronic ballast.

Abstract: In examples of the embodiment, a surge-proof interface circuit (100) comprises a rectifier circuit (20) which is configured to produce a rectified rectifier output voltage at the rectifier output terminals (20c, 20d), in accordance with a rectifier input voltage at the rectifier input terminals (20a, 20b), and a Darlington circuit (30) which comprises at least two transistors (Q3, Q4). Said Darlington circuit (30) comprises a current path (35) which can be controlled on the output side in accordance with a control signal (62) and said current path (35) which can be controlled on the output side is coupled between the rectifier output connections (20c, 20d).

Abstract: A light emitting diode (LED) driver circuit is provided. The LED driver circuit includes an LED the LED; a power unit which provides a current to the LED through an inductor; a dimming switch which is connected to the LED and bypasses the current provided to the LED; an input unit which receives brightness information of the LED; a logic unit which calculates reference currents for each driving mode according to the received brightness information; a current control unit which controls the power unit to provide the current based on the driving mode and the calculated reference currents to the inductor; and a switch control unit which switches the dimming switch on if the driving mode of the LED driver circuit is switched to the dimming mode.

Abstract: An electric protection mechanism for a light controller includes an overload protection device. The overload protection device includes a lamplight controller, a power controller, and a load detector. A current sensor is provided between the power controller and a light. An overload detector is provided to detect the state of the electric current anytime. Once abnormal current is outputted to the light, the power controller immediately shuts its output and informs the lamplight controller of the abnormal current. The lamplight controller will reset its process, such as to shut down the power source or to press the button so as to return to normal. Thus, the lamplight controller, a light adjuster or a remote controller can be protected. The present invention provides an overload protection function, and it is safe to use the present invention.

Abstract: Various embodiments provide a fuse for a light emitting diode fluorescent lamp retrofit lamp, the fuse including a first electrical fuse connecting element for the electrical connection to an electric socket connecting element of a socket of the light emitting diode fluorescent lamp retrofit lamp; and a second electrical fuse connecting element for the electrical connection to a driver of the light emitting diode fluorescent lamp retrofit lamp; wherein the first fuse connecting element is designed as a connecting pin which is provided and equipped for a rigid connection to the socket connecting element.

Abstract: A switching power circuit includes a first switching element having one end connected to a positive electrode of a first capacitor, a second switching element having one end connected to a negative electrode of the first capacitor, an inductive element having one end connected to the other ends of the first and the second switching element, a semiconductor switching element connected in parallel to the current limiting resistor, and a second capacitor connected to a control electrode of the semiconductor switching element. The second capacitor is charged by using a voltage induced to the inductive element when the first or the second switching element is off.

Abstract: A light emitting diode (LED) driver circuit controls switching of an output transistor. The LED driver circuit monitors inductor current flowing through an output inductor that is coupled to one or more LEDs. In response to detecting that the inductor current has reached a peak value, the LED driver circuit switches OFF the output transistor. The LED driver circuit switches ON the output transistor in response to detecting zero crossing of the inductor current. The LED driver circuit may detect zero crossing of the inductor current from a gate voltage of the output transistor by detecting for a negative spike.

Abstract: A high-voltage pulse generator based on a spiral pulse generator, wherein the spiral pulse generator is implemented as an LTCC component and is wound from at least two ceramic and at least two metal-containing layers, and the high-voltage pulse generator can be introduced into a cylindrical volume V=d2*?*3*d whose length is three times as long as the diameter of the volume, and the volume of the high-voltage pulse generator is greater than one-third of the cylindrical volume. Also disclosed is a high-pressure discharge lamp having a tubular outer piston, wherein the outer piston of the high-pressure discharge lamp has an aforesaid high-voltage pulse generator.

Abstract: A representative apparatus embodiment provides for controlling current supplied to solid state lighting, such as light emitting diodes. A representative apparatus comprises a memory adapted to store a plurality of current parameters, and a control circuit adapted to modulate an energizing cycle time period for providing a substantially constant DC average current to the solid state lighting in response to a selected current parameter from the plurality of current parameters. In a representative embodiment, the control circuit modulates a current provided to the solid state lighting in response to a predetermined minimum current level (IMIN) parameter and a predetermined peak current level (IP) parameter, such that the DC average current level (IO) is substantially proportional to one-half of a sum of a predetermined peak current level (IP) and a predetermined minimum current level IMIN ( I O ? I P + I MI ? ? N 2 ) .

Abstract: An illumination system detects a peak value of a voltage of a transformer supplying an LED module by analyzing the current value of the voltage and an on-time of the voltage. Based on the detected peak value, a property of the illumination system is adjusted.

Abstract: A lighting device which lights the discharge lamp, includes: a converting circuit which converts the direct current into an alternating current; a pulse generating circuit which generates a high voltage pulse; and a trigger circuit which causes the pulse generating circuit to generate the high voltage pulse, wherein the pulse generating circuit includes a primary winding and a secondary winding and generates the high voltage pulse by increasing a current input to the secondary winding based on a current input to the primary winding, and the trigger circuit includes a high pass filter; a first capacitor which stores and discharges charges input via the high pass filter; and a third switching element which outputs an output current from a second capacitor connected in parallel to the converting circuit to the primary winding if an output voltage from the first capacitor exceeds a threshold.

Abstract: An ignition transformer for a discharge lamp is provided having a transformer core whose material and dimensions are selected in such a manner that the Curie temperature of the material after the ignition which is achieved by means of the ignition transformer can be achieved by a voltage drop across a secondary winding of the ignition transformer.

Abstract: A light emitting diode (LED) driver circuit is provided. The LED driver circuit includes an LED the LED; a power unit which provides a current to the LED through an inductor; a dimming switch which is connected to the LED and bypasses the current provided to the LED; an input unit which receives brightness information of the LED; a logic unit which calculates reference currents for each driving mode according to the received brightness information; a current control unit which controls the power unit to provide the current based on the driving mode and the calculated reference currents to the inductor; and a switch control unit which switches the dimming switch on if the driving mode of the LED driver circuit is switched to the dimming mode.

Abstract: A driving circuit for driving a light-emitting diode (LED) light source includes a buck-boost converter and a controller. The buck-boost converter receives an input voltage and an input current and powers the LED light source, and comprises a switch controlled by a driving signal. The controller receives a first signal indicating a current through the LED light source, and generates the driving signal based on the first signal to control the switch and to adjust the current through the LED light source. The buck-boost converter further comprises a current sensor which provides a second signal indicating an instant current flowing through the buck-boost converter, wherein the first signal is derived from the second signal, and wherein a reference ground of the controller is different from a ground of the driving circuit.

Abstract: An LED module (10) for operating at least one LED (18) comprising an input (E1, E2) adapted for coupling to a DC voltage source (UE); an output (A1, A2) adapted for coupling to the at least one LED (18); a filter device (14); and a DC-DC converter (16); wherein the filter device (14) and the DC-DC converter (16) are coupled in series between the input (E1, E2) and the output (A1, A2), and wherein the output (DCA1, DCA2) of the DC-DC converter (16) is coupled to the output (A1, A2) of the LED module (10); wherein the LED module further comprises an electronic switch (Q1), which is configured to couple the DC-DC converter (16) to the input (E1, E2) of the LED module (10) and to decouple it therefrom.

Abstract: An exemplary apparatus embodiment provides for controlling current supplied to solid state lighting, such as light emitting diodes. An exemplary apparatus comprises a memory adapted to store a plurality of current parameters; and a control circuit adapted to modulate an energizing cycle time period for providing a substantially constant DC average current to the solid state lighting in response to a selected current parameter of the plurality of current parameters. In an exemplary embodiment, the control circuit modulates a current provided to the solid state lighting in response to a predetermined minimum current level (IMIN) parameter and a predetermined peak current level (IP) parameter, such that the DC average current level (IO) is substantially proportional to one-half of a sum of a predetermined peak current level (“IP”) and a predetermined minimum current level I M ? ( I O ? I P + I MIN 2 ) .

Abstract: An exemplary power regulator apparatus provides power for illumination of a display object, such as a merchandise package or container, which has a light emitting apparatus comprising a secondary inductor and an illumination source. A support structure, such as a point of purchase display, typically contains or supports one or more power regulators and display objects. The power regulator comprises a controller and a primary inductor, and the controller is adapted to provide a voltage or current to the primary inductor to generate a primary inductor voltage. The controller may also comprise a plurality of switches and a memory adapted to store values for switching frequency or switch on-time durations or pulse widths. The illumination source emits visible light when the power regulator is in an on state and when the secondary inductor is within a predetermined distance of the primary inductor.

Abstract: An LED lamp protecting circuit includes an LED lamp, a constant current source and a buffer circuit. The constant current source includes positive and negative input terminals, positive and negative output terminals and a switch. The buffer circuit is connected between the negative output terminal and the LED lamp. The buffer circuit includes a charging capacitor, a first NPN transistor and a second PNP transistor. An emitting electrode of the second transistor is connected to the LED lamp. A collecting electrode of the second transistor is connected to the negative output terminal. The charging capacitor is connected between the emitting electrode of the second transistor and a ground. A collecting electrode and an emitting electrode of the first transistor are respectively electrically connected to a base electrode of the second transistor and the ground.

Abstract: A spiral pulse generator is used to start the high-pressure discharge lamp, and is accommodated directly in the outer bulb of the lamp. The spiral pulse generator uses a material with a matched ? and ?.

Abstract: A starting circuit of a starting device for a high-pressure discharge lamp including an auxiliary light source has a diode placed in a forward direction in one of a pair of output lines which connect a main lighting circuit for generating AC voltage to the high-pressure discharge lamp and the auxiliary light source; a capacitor having one end connected to a cathode side of the diode; a boosting transformer including a primary winding, and a secondary winding having one end connected to an anode side of the diode or to the other output line and also having the other end connected to the other end of the capacitor; a high-frequency voltage generation circuit for continuously generating high-frequency voltage in combination with the primary winding; and a short-circuit switch for maintaining a short-circuit condition at both ends of the diode after the high-pressure discharge lamp is started.

Abstract: A constant current source mirror tank dimmable ballast operates multiple high impedance lamps in a stable and balanced manner. The dimmable ballast has an inverter connected to two third-order resonant circuits. These third-order resonant circuits dominate the transfer function of the ballast circuits. Consequently, changes in the impedance of the lamp do not affect the current output to the lamps.

Abstract: The invention relates to a switching arrangement for an ignition device of a discharge lamp (1), comprised of a spark gap formed by three or more electrodes (11) and connected in series with the primary winding (8) of a superimposed transformer (3) and a surge capacitor (9). The invention proposes a cylindrically shaped configuration for the electrodes (11), with the cylinder axes (12) being arranged side by side and in parallel to each other, i.e. in such a manner that a multiple-stage spark gap in air is formed vertically to the cylinder axes (12). Furthermore, the invention relates to an ignition device for a high-pressure discharge lamp.

Abstract: A method and apparatus for aiding ignition in a discharge lamp is provided. In one embodiment, a method comprises: applying a voltage across a pair of electrodes of a discharge lamp and capacitively coupling the discharge lamp. The capacitive coupling of the discharge lamp induces a current in the lamp to lower an ignition voltage of the discharge lamp. In another embodiment, a circuit for aiding ignition in a discharge lamp comprising a first electrode and a second electrode is also provided. The circuit comprises a lamp drive circuit comprises a voltage source coupled to a first terminal and a current controller coupled to a second terminal. The first and second terminals are configured to couple to a corresponding one of the first electrode and the second electrode of the discharge lamp. The voltage source is configured to provide a voltage signal at the first terminal and the current controller is configured to control a current received via the second terminal.

Abstract: A lamp ignition circuit provides a high voltage electrical pulse to ignite a gas discharge lamp. A non-linear filter element within a charge circuit regulates the voltage of the ignition pulse such that the ignition pulse remains within a prescribed voltage range over a wide variety of conduit lengths between the lamp and the lamp ignition circuit. This allows for the ballast and lamp ignition circuit to be mounted either close to the lamp or far from the lamp without modifying the ignition circuitry.

Abstract: The invention is a device for operating a high-pressure gas discharge lamp, which is provided with a starting auxiliary electrode, with a current of alternating polarity. The device has a series resonance circuit with a resonance inductive resistor, through which flows the lamp current when the lamp is in operation, and a starting device for subjecting the starting auxiliary electrode to the starting voltage required for starting the gas discharge in the high-pressure gas discharge lamp. There is also a capacitive component, which is connected in series to the resonance inductive resistor and is dimensioned in such a manner that the capacitive component effects, after the gas discharge in the high-pressure gas discharge lamp has been started, at least a partial compensation for the inductance of the resonance inductive resistor, through which the lamp current flows.

Abstract: A lamp assembly includes a housing that selectively receives a removable, plug-in high intensity discharge (HID) lamp. A transformer and electrical circuit are received in the housing for providing an instant start, hot re-strike ignition of the lamp at less than 25 kilovolts. A circuit for an instant start, hot re-strike of an HID lamp supplies an ignition voltage to the HID lamp that includes pulses having an amplitude of less than 25 kilovolts and a frequency ranging from approximately 20 hertz to approximately 500 hertz. Preferably, the frequency is greater than 100 hertz, more preferably the frequency is approximately 150 hertz. The amplitude of pulses are preferably less than approximately 15 kilovolts, and more preferably approximately 8-10 kilovolts. The pulse width is approximately 200 nanoseconds and the peaks of the pulses are periodic with a period of approximately 2 milliseconds.

Abstract: An object of the invention is to provide a high-pressure discharge lamp lighting device capable of executing dimming up to a lower luminous flux level than the dimming lower limit obtained by performing constant-current control in related arts. A high-pressure discharge lamp lighting device of the invention includes power conversion unit for supplying AC power to a high-pressure discharge lamp as a load with a DC power supply as an input power supply for performing all lighting or dimming lighting. In an area where the voltage across the high-pressure discharge lamp grows as dimming deepens, the output characteristic of the power conversion unit is a characteristic for increasing the output current of the power conversion unit in response to an increase in the output voltage of the power conversion unit.

Abstract: An apparatus for radiating an object with UV-radiation, the apparatus comprises a series arrangement of an incandescent lamp (LA1) and a gas discharge UV lamp (L2) which generates at least UV light. The series arrangement is arranged for receiving current (IP) from an AC power source (PS). A filament of the incandescent lamp (LA1) forms a ballast for the gas discharge UV lamp (LA2). A HF generator (OSC) generates a generator current (IOSC) through the gas discharge UV lamp (LA2), at least when an AC-voltage (VM) generated by the AC power source (PS) is lower than an ignition voltage of the gas discharge UV lamp (LA2), to keep the gas discharge UV lamp (LA2) ionized.

Abstract: A spiral pulse generator is used to start a high-pressure discharge lamp and is accommodated directly in the external bulb of the lamp. The spiral pulse generator comprises two parts which are manufactured jointly as an LTCC component.

Abstract: A discharge lamp lighting circuit 1 includes a direct current-alternating current converting circuit 3, a starting circuit 4, controlling means 15 for controlling power, switching elements 5H, 5L driven by the controlling means 15 and a series LC resonance circuit (7p, 8, 9). A frequency modulating circuit is provided for restraining acoustic resonance by modulating a frequency of driving the switching element. When a basic frequency related to the drive frequency is equal to or higher than 1 MHz, a modulation width is set to be equal to or higher than 20 kHz.

Abstract: A circuit for the generation of ignition pulses for a lamp has: an ignition pulse transformer, a device for the generation of ignition pulses (ignition pulse generator) at a primary winding of the ignition pulse transformer, which are transformed in the secondary winding of the ignition pulse transformer, a voltage detector for the detection of the voltage value of the transformed ignition pulses, and a voltage regulator for regulating the voltage value of the transformed ignition pulses to a predetermined reference value. The ignition pulse generator has, in a series circuit, a pulse capacitor and a switch, parallel to the secondary winding of the ignition pulse transformer and the lamp, wherein the regulator for the voltage value of the transformed ignition pulses sets at the pulse capacitor the voltage applied at an ignition time point. The voltage at the pulse capacitor can be set by means of selection of the switch-on and/or switch-off time points of the switch.

Abstract: A magnetic ballast fault isolation system and method, with a fault isolation system including a magnetic ballast 22 having a current input 24, the magnetic ballast 22 having an operational current rating and an inrush current rating; and a fast acting fuse 26 operably connected in series with the current input 24, the fast acting fuse 26 having a continuous current rating and an overload current rating. The amperage of the fast acting fuse 26 is selected for the larger of the continuous current rating for a predetermined current factor times the operational current rating and the overload current rating for the inrush current rating.

Abstract: Even if a DC output voltage of a step-down chopper circuit (3) is lowered from a value in a non-lighted state or a no-load state due to a discharge occurring between conductors (105a) in a cable (104), the turn on detection circuit (26a) can discriminates between lighted and non-lighted states without erroneously determining such a discharge as a discharge in a discharge lamp (4). This allows an operation of the timer (29) to be continued, so that high-voltage pulses are intermittently applied to prevent continuous discharge between the conductors (105) and abnormal heat generation in the cable (104). Further, even if a discharge occurs in an outer tube of the discharge lamp (4), the turn on detection circuit (26a) never erroneously discriminates this discharge as the lighted state. Thus, the lighting device of the present invention can suppress abnormal heat generations in the components and a socket (102).

Abstract: There is provided a high-intensity discharge lamp lighting apparatus to be loaded with a plurality of types of high-intensity discharge lamps and connected with any one of the lamps to be lighted, and the apparatus comprises a power conversion circuit for converting power supplied from a DC power source to supply the power to a high-intensity discharge lamp and a lighting control circuit for controlling the supply power of the power conversion circuit, wherein the type of the connected high-pressure discharge lamp is determined based upon a change rate of an electric characteristic of the high-intensity discharge lamp during a specific period, and the connected high-intensity discharge lamp is lighted with a desired electric characteristic selected based upon the determination result, thereby enabling discrimination of types of rated power of the plurality of types of lamps by the same detection method and the same control method irrespective of states in starting of the lamps, and by enabling the discriminat

Abstract: A lighting assembly, a driver circuit, and a method of operating a discharge lamp are described. A discharge lamp (10) comprises a discharge vessel (14) with at least two electrodes (16) arranged at a distance d for generating an arc between the electrode (16). Driver electronics (32) operate the lamp (10) with electrical power. In order to reduce electrode burn-back, the driver electronics operate the lamp according to a switch-off sequence, which includes a power ramp interval (24) where the lamp (10) is operated with increasing electrical power over time, and subsequently the lamp (10) is switched-off.

Abstract: A discharge-lamp lighting apparatus includes a control circuit that determines electric power supplied to a high-pressure discharge lamp after the high-pressure discharge lamp is started by an igniter. The electric power is determined in accordance with a voltage corresponding to a lamp voltage detected by a voltage detection circuit and a drive current detected by a current detection circuit. When the determined electric power is less than predetermined electric power, the control circuit causes a down chopper to control the drive current such that an amount of increase in the electric power per unit time becomes equal to or less than a predetermined value.

Abstract: A DC-DC converter reduces a surge voltage developed across a switching element (30) in making the voltage conversion with the use of a transformer (20) inherently having considerable leakage. A snubber circuit is included to absorb the surge energy and transferring it to a load, or output end of the converter, reducing the surge voltage across the switching element (30). A snubber capacitor (51) is provided to absorb the surge energy developed by the transformer (20) when the switching element (30) is off. Thus absorbed energy is collected in a storage capacitor (53) through a reactor (54) while the switching element (30) is on and off, and is then transferred from the storage capacitor (53) to the load, i.e., the output side of the converter, leaving only a minimum voltage being applied across the switching element (30).

Abstract: To provide a lighting circuit of a projector that can be driven by both the commercial alternating-current power supply and a battery and is convenient for portable use.

Abstract: A lamp ballast for operating a high intensity discharge lamp includes an electronic ballast circuit to supply an operating voltage to the discharge lamp, and an igniter circuit to supply starting pulses to the discharge lamp in a cold state and to supply hot restrike pulses to the discharge lamp when the discharge lamp is in a hot state following turn-off. The hot restrike pulses are sufficient to maintain ionization in the discharge lamp but do not cause the discharge lamp to generate substantial light output.

Abstract: The present discharge lamp lighting device is capable of rapid modulation in which a lamp current is rapidly reduced and rapidly restored. The current control circuit is provided to perform specific current control such that the brightness of a lamp is reduced by a predetermined percentage without being affected by a variation or change in lamp voltage over time, thereby reducing a lamp current.

Abstract: Systems and methods are disclosed that facilitate sensing a pulse in a ballast circuit for a lamp when the lamp is in an end-of-life (EOL) stage or when the lamp is experiencing an arcing conduction condition, such as may occur when a contact between the lamp and its holder is compromised. Upon sensing the pulse, a microcontroller may distinguish between EOL and arcing conditions based on detected pulse width(s), and may initiate an appropriate response. For instance, if the pulse is due to an arcing event, the microcontroller may interrupt lamp operation for a brief period before restarting the lamp to mitigate the arcing condition. If the pulse is caused by an EOL condition, the microcontroller may place the lamp in a preheat or restarting mode to hasten lamp failure. In either case, responses to the sensed pulse mitigate the occurrence of dangerously high lamp temperatures that may damage lamp sockets.

Abstract: The instant invention relates to an HID ballast and lamp tester, which provides visual indication of failure of either the ballast or lamp by continuously monitoring the status of the HID lighting system. The HID ballast and lamp tester detects and utilizes the voltage difference between the open circuit voltage and the operating voltage of the ballast to trigger visual indication of the open circuit voltage output of the ballast when the HID lamp has failed. The tester circuit comprises the ballast source, a full wave bridge rectifier and filter capacitor circuit, a voltage divider network circuit, a trigger circuit of a diac bi-directional silicon switch and a light emitting diode.

Abstract: A stabilizer circuit for a high-voltage discharge lamp is provided. The stabilizer comprises an electromagnetic interference (EMI) filter; a rectifying unit; a power factor correction (PFC) circuit; a buck converter; a commutator; an igniter; a high-voltage discharge lamp; a current detector; a voltage detector; an igniter voltage controller for receiving the voltage output from the igniter and controlling the voltage when abnormality in the high-voltage discharge lamp occurs.

Abstract: A device for operating a discharge lamp of the alternating current operating type has a high pressure discharge lamp with a silica glass discharge vessel in which a pair of opposed electrodes are located and on which a trigger electrode is located, a feed device which supplies an alternating discharge current to the high pressure discharge lamp, the feed device having a starter circuit, an inverter circuit with at least two switching devices; a coil which is located downstream of the inverter circuit and is series-connected to the discharge lamp; and a control element which produces on/off driving in alternation with a dead time, and in which the inductance of the coil is at most 210 ?H.

Abstract: In an operating method for a lighting system and a lighting system in which a readiness command is provided, in response to such readiness command a ballast drives a discharge lamp in such a way that it heats the electrodes further if the discharge lamp is not burning, so that a controller can use a switch-on command to reignite the discharge lamp without delay by means of a preheating time.

Abstract: A lighting device for an ac-lighting type ultra-high pressure mercury lamp includes: a stepdown chopper for converting dc voltage that is supplied from the outside to voltage of a prescribed level; a full-bridge switch circuit for generating either dc or ac voltage from the output voltage of the stepdown chopper and supplying the generated voltage to the ultra-high pressure mercury lamp; and a control circuit for controlling the full-bridge switch circuit such that, when extinguishing the lamp, a dc voltage is supplied over a prescribed time interval with a prescribed electrode of the ultra-high pressure mercury lamp as the anode.