EP0477922A1 - Appareil pour le fonctionnement d'une lampe à décharge - Google Patents

Appareil pour le fonctionnement d'une lampe à décharge Download PDF

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Publication number
EP0477922A1
EP0477922A1 EP91116369A EP91116369A EP0477922A1 EP 0477922 A1 EP0477922 A1 EP 0477922A1 EP 91116369 A EP91116369 A EP 91116369A EP 91116369 A EP91116369 A EP 91116369A EP 0477922 A1 EP0477922 A1 EP 0477922A1
Authority
EP
European Patent Office
Prior art keywords
power supply
discharge lamp
temperature
lamp current
lamp
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP91116369A
Other languages
German (de)
English (en)
Inventor
Mitsutoshi Kimura
Akio Ishizuka
Katsuaki Nakano
Yoshinobu Onodera
Yoshinori Satou
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toshiba Lighting and Technology Corp
Original Assignee
Toshiba Lighting and Technology Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Toshiba Lighting and Technology Corp filed Critical Toshiba Lighting and Technology Corp
Publication of EP0477922A1 publication Critical patent/EP0477922A1/fr
Withdrawn legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B41/00—Circuit arrangements or apparatus for igniting or operating discharge lamps
    • H05B41/14—Circuit arrangements
    • H05B41/36—Controlling
    • H05B41/38—Controlling the intensity of light
    • H05B41/39—Controlling the intensity of light continuously
    • H05B41/392—Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor
    • H05B41/3921—Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor with possibility of light intensity variations
    • H05B41/3927—Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor with possibility of light intensity variations by pulse width modulation
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B41/00—Circuit arrangements or apparatus for igniting or operating discharge lamps
    • H05B41/14—Circuit arrangements
    • H05B41/36—Controlling
    • H05B41/38—Controlling the intensity of light
    • H05B41/39—Controlling the intensity of light continuously
    • H05B41/392—Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B41/00—Circuit arrangements or apparatus for igniting or operating discharge lamps
    • H05B41/14—Circuit arrangements
    • H05B41/24—Circuit arrangements in which the lamp is fed by high frequency ac, or with separate oscillator frequency
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B41/00—Circuit arrangements or apparatus for igniting or operating discharge lamps
    • H05B41/14—Circuit arrangements
    • H05B41/36—Controlling

Definitions

  • the present invention relates to an apparatus for operating a discharge lamp, particularly to an apparatus for operating a discharge-lamp capable of changing the lower limit of the lamp current at a low temperature.
  • a conventional apparatus for operating a discharge lamp for example, a back light for use in an electronic device, such as a computer, which can change the lamp current whether either a battery or a commercially available AC power supply is used.
  • the AC power supply for example, the luminance of the discharge lamp is set high regardless of power consumption in the electronic device.
  • the luminance of the discharge lamp drops to a lower level to save the power, thus ensuring a longer use of the discharge lamp with the battery.
  • an apparatus for operating a discharge lamp which comprises a discharge lamp; power supply means, connected to the discharge lamp, capable of setting a value of a lamp current of the discharge lamp in at least two levels; a DC power supply section, connected to the power supply means, for supplying a predetermined voltage; temperature detecting means, connected to the power supply means, for detecting a temperature of the discharge lamp or the ambient temperature thereof; and control means for performing control to allow the lamp current set by the power supply means to increase when the temperature detected by the temperature detecting means is equal to or below a given temperature, and the value of the lamp current is set equal to or below a predetermined value by the power supply means.
  • an apparatus for operating a discharge lamp which comprises a discharge lamp; power supply means, connected to the discharge lamp, capable of setting a value of a lamp current of the discharge lamp in at least two levels; a DC power supply section, connected to the power supply means, for supplying DC voltages corresponding to the at least two levels; temperature detecting means, connected to the power supply means, for detecting a temperature of the discharge lamp or the ambient temperature thereof; and control means for performing control to allow the lamp current set by the power supply means to increase when the temperature detected by the temperature detecting means is equal to or below a given temperature, and the value of the lamp current is set equal to or below a predetermined value by the power supply means.
  • Fig. 1 illustrate the circuit structure a lighting apparatus for a discharge lamp according to this embodiment of the present invention.
  • a capacitor C1 and an electrolytic capacitor C2 are connected in parallel as filters via a DC power supply 12 and a fuse F1.
  • a variable stable power supply 10 and an inverter circuit 20 are connected in series to the electrolytic capacitor C2.
  • a temperature detector 30 as temperature detecting means is connected to the variable stable power supply 10.
  • a discharge lamp 40 is connected to the inverter circuit 20.
  • an inductor L1 (used for accumulating power), a diode D1 having the polarity shown in Fig. 1 and used for preventing a reverse current flow, and the emitter of an ON/OFF transistor Q1 are connected in the named order to the fuse F1.
  • a bias resistor R1 is connected between the base and emitter of the transistor Q1 whose base is connected via a resistor R2 to an ON/OFF terminal.
  • a series circuit including a resistor R3 and a diode D2 is connected in parallel to the inductor L1.
  • the emitter of the transistor Q2 is connected to a point where the fuse F1 is connected to the inductor L1.
  • a bias resistor R4 is connected between the emitter and base of the transistor Q2 whose base is connected to the ON/OFF terminal via resistors R5 and R6.
  • the transistor Q2 has its collector connected to a GND terminal via a Zener diode ZD1, resistors R7 and R8 and a diode D3.
  • a field-effect transistor Q3 Connected to a connecting point between the inductor L1 and the diode D1 is the drain of a field-effect transistor Q3 which changes a duty ratio to vary the output of the variable stable power supply 10.
  • the source of the transistor Q3 is connected to the GND terminal.
  • a resistor R9 is connected between the source and drain of the transistor Q3.
  • a capacitor C3 is connected between the cathode of the diode D1 and the GND terminal.
  • a series circuit which has a resistor R10, a variable resistor R11 and a semi-fixed resistor R9, and a smoothing electrolytic capacitor C4 are connected in parallel between the collector of the transistor Q1 and the GND terminal.
  • the variable resistor R11 serves as a volume to change the dimming of the discharge lamp 40.
  • IC1 is, for example, a TL494 IC chip produced by Texas Instrument Corp.
  • the IC chip IC1 has its terminal 1 connected to the GND terminal via a capacitor C5.
  • a resistor R13 and a capacitor C6 are connected in parallel to each other between terminals 2 and 3 of the IC chip IC1.
  • a connecting point between the resistors R7 and R8 is connected to a terminal 4 of the IC chip IC1.
  • the IC chip IC1 also has terminals 5 and 6 connected to the GND terminal respectively via a capacitor C7 and a resistor R14. Terminals 7, 13 and 16 of the IC chip IC1 are directly connected to the GND terminal.
  • the IC chip IC1 has terminals 8 and 11 connected to the collector of the transistor Q2 via a parallel circuit including a resistor R15 and a capacitor C8, and has a terminal 12 directly connected to the collector of the transistor Q2.
  • Terminals 14 and 15 of the IC chip IC1 are connected to the emitter of a transistor Q4 for selecting an input in accordance with switching between the commercially available AC power supply and the battery, for example.
  • a bias resistor R16 is connected between the emitter and base of the transistor Q4, with an input selecting terminal connected to that base.
  • a resistor R18 is connected to the collector of the transistor Q4, while a parallel circuit having an electrolytic capacitor C9 and a resistor R19 is connected via the resistor R18 between the collector and the emitter of the transistor Q4.
  • a point where the resistor R18, the electrolytic capacitor C9 and the resistor R19 are connected is connected via a resistor R20 to a parallel circuit having a resistor R13 and a capacitor C6, and also connected to the GND terminal via a resistor R21.
  • the capacitor C9 and resistors R19 and R21 form a time constant circuit. Even if the time constant circuit is in a dimming state, it supplies a high power to the discharge lamp 40 at the start thereof, thereby enabling the lamp to start discharging and light up in a reliable manner. Capacitor C9 of the time constant circuit prevents a rapid decrease in the brightness of the lamp 40 in the case where transistor Q4 is changed from ON to OFF by a signal supplied from the input selecting terminal.
  • the temperature detector 30 has a transistor Q5.
  • the transistor Q5 has a collector connected via a resistor R22 to the collector of the transistor Q4, an emitter connected to the emitter of the transistor Q4, and a base connected via a resistor R23 to the GND terminal.
  • a thermistor Th1 Connected between the emitter and base of the transistor Q5 is a thermistor Th1 which is attached to, for example, the wall of the tube of the discharge lamp 40.
  • the inverter circuit 20 is connected between one end of the electrolytic capacitor C4 as the positive terminal of the variable stable power supply 10, and the other end as the negative terminal thereof.
  • An intermediate tap T1at of a primary winding T1a of a first transformer T1 is connected via an inductor L2 in the inverter circuit 20 to the positive terminal of the variable stable power supply 10.
  • a resonance capacitor C10 is connected to the primary winding T1a in parallel.
  • the primary winding T1a has one end connected via the collector and emitter of a transistor Q6 to the negative terminal of the variable stable power supply 10.
  • the other end of the primary winding T1a is connected via the collector and emitter of a transistor Q7 to the negative terminal of the variable stable power supply 10.
  • a second transformer T2 has its primary winding T2a connected in parallel to the primary winding T1a of the transformer T1 and the capacitor C10.
  • the second transformer T2 has a control winding T2c connected to the bases of the transistors Q6 and Q7.
  • the first transformer T1 and the second transformer T2 have the secondary winding T1b and second winding T2b connected in series via capacitors C11 and C12 to the discharge lamp 40, or, for example, a cold-cathode tube for a back light used in an office automation device.
  • the secondary winding T1b of the first transformer T1 and the secondary winding T2b of the second transformer T2 are commonly grounded and are connected to the negative terminal of the variable stable power supply 10.
  • the output of the variable stable power supply 10 becomes constant by changing the resistance of the variable resistor R11 through feedback control.
  • the input signal from the input selecting terminal becomes a high level, rendering the transistor Q4 off.
  • the width of a PWM modulated pulse output from the terminals 9 and 10 of the IC chip IC becomes relatively small.
  • the ON duration of the field-effect transistor Q3 decreases.
  • the output of the variable stable power supply 10 decreases so that the brightness of the discharge lamp 40 is about 30% of that in the case where the AC power is used.
  • the resistance of the thermistor Th1 is raised to render the transistor Q5 on.
  • the width of a PWM modulated pulse output from the terminals 9 and 10 becomes a little larger, and the ON duration of the field-effect transistor Q3 is also increased slightly.
  • the output of the variable stable power supply 10 is increased so that the brightness of the discharge lamp 40 becomes 45% of that in the case where the AC power is used, thus preventing the lighting failure of the discharge lamp 40.
  • the proper voltage is selected within the range of 11 V to 15 V as indicated by B1 or B2 in Fig. 2, for example, by changing the resistance of the variable resistor R11. If the temperature is below 15°C, the voltage increases. In other words, when the temperature is below 15°C, the voltage is held at about 15 V, no matter where in the range of 11 V to 15 V the set voltage is.
  • R19a (broken lines) and R19b (real line) in Fig. 2 indicate changes in output of the power supply (input of the inverter circuit) when different discharge lamps with different resistors R19 are used.
  • the output characteristic curves indicated by R19a and R19b show the operational limit of the discharge lamp 40 driven by the battery when the resistor R19 is used.
  • the DC current from the variable stable power supply 10 is supplied via the inductor L2 for a constant current and either transistor Q1 or Q2 is rendered on, so that the inverter circuit 20 is activated.
  • the transistors Q6 and Q7 are alternately turned on.
  • the current flows in a closed circuit from the variable stable power supply 10, to the inductor L2, to the half of the primary winding T1a of the first transformer T1, to the transistor Q6, and then back to the variable stable power supply 10.
  • the capacitor C10 resonates with the primary winding T1a, and hence a high frequency voltage having a substantial sine waveform is created in the secondary winding T1b.
  • a voltage similar to this sine wave voltage is created in the secondary winding T2a of the second transformer T2, parallel connected to the primary winding T1a.
  • the voltages of the secondary winding T1b of the first transformer T1 and the secondary winding T2b of the second transformer T2 are added to each other, and the resultant voltage is applied to the discharge lamp 40.
  • the resonance voltage is inverted, and the transistor Q6 is turned off.
  • the transistor Q7 When the transistor Q7 is turned on, the current flows in a closed circuit from the variable stable power supply 10, to the inductor L2, to the half of the primary winding T1a of the first transformer T1, to the second transformer T2, and then back to the variable stable power supply 10.
  • the capacitor C10 resonates with the primary winding T1a, and hence a high frequency voltage having a substantial sine waveform is created in the secondary winding T1b.
  • a voltage similar to this sine wave voltage is created in the secondary winding T2a of the second transformer T2, parallel connected to the primary winding T1a.
  • a voltage is induced, in the opposite direction to that in the previous case, in the secondary winding T2b of the second transformer T2.
  • the voltages of the secondary winding T1b of the first transformer T1 and the secondary winding T2b of the second transformer T2 are added to each other, and the resultant voltage is applied to the discharge lamp 40.
  • the output of the discharge lamp 40 is reduced to save the power with the battery in use, the output of the discharge lamp 40 rises when the temperature drops to a predetermined degree or lower. Lighting failure can be prevented.
  • the output of the discharge lamp 40 when the battery is used, can be determined in consideration of only lighting failure of the discharge lamp 40 at the normal temperature. The output of the discharge lamp 40 can therefore be suppressed very low to save the power sufficiently. Since the output of the discharge lamp 40 does not increase at a low temperature when the AC power is used, the discharge lamp 40 is not influenced by the low temperature.
  • the voltage of the discharge lamp 40 is acquired by superimposing the voltages induced in the secondary windings T1b and T2b of the first and second transformers T1 and T2, respectively.
  • the voltages to be induced in secondary windings T1b and T2b can be low, thus permitting the first and second transformers T1 and T2 to be designed compact.
  • the thermistor Th1 in the temperature detector 30 may be attached not only to the tube wall of the discharge lamp 40, but also to the radiating plate of the transistor, capacitor, coil or the like.
  • Fig. 3 illustrates the circuit structure of a lighting apparatus for a discharge lamp according to another embodiment of the present invention.
  • a DC power supply 14, which provides a DC voltage acquired by rectifying commercially available AC power and a battery 16 are connected in parallel to each other via power switches SW1 and SW2 between the Vcc terminal and the GND terminal.
  • An input selecting switch SW3 interposed between the input switching terminal and ground line is associated with the switches SW1 and SW2.
  • the other structure in this circuit is the same as that of the circuit shown in Fig. 1, so that their otherwise redundant description will be omitted.
  • the input selecting switch SW3 When the switch SW1 is off, and the switch SW2 is on, the input selecting switch SW3 is off.
  • the battery 16 is therefore connected between the Vcc terminal and the GND terminal. Since the input selecting switch SW3 is off this time, the transistor Q4 is rendered off.
  • the operation associated with this event is the same as that in the first embodiment, so that its description will be omitted.
  • the type of the power supply to be connected is selected by switching the input selecting switch SW3.
  • the output of the discharge lamp 40 is raised when the temperature drops to a predetermined value or lower, thus preventing lighting failure.

Landscapes

  • Circuit Arrangements For Discharge Lamps (AREA)
  • Discharge-Lamp Control Circuits And Pulse- Feed Circuits (AREA)
EP91116369A 1990-09-25 1991-09-25 Appareil pour le fonctionnement d'une lampe à décharge Withdrawn EP0477922A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP25454290A JP3196206B2 (ja) 1990-09-25 1990-09-25 放電ランプ点灯装置
JP254542/90 1990-09-25

Publications (1)

Publication Number Publication Date
EP0477922A1 true EP0477922A1 (fr) 1992-04-01

Family

ID=17266492

Family Applications (1)

Application Number Title Priority Date Filing Date
EP91116369A Withdrawn EP0477922A1 (fr) 1990-09-25 1991-09-25 Appareil pour le fonctionnement d'une lampe à décharge

Country Status (3)

Country Link
EP (1) EP0477922A1 (fr)
JP (1) JP3196206B2 (fr)
KR (1) KR940004786B1 (fr)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2707054A1 (en) * 1993-06-21 1994-12-30 Valeo Vision DC converter for supplying an electric load, especially a fluorescent tube
EP0804052A2 (fr) * 1996-04-24 1997-10-29 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Circuit de commande pour une lampe à décharge
US5705897A (en) * 1994-07-12 1998-01-06 Mitsubishi Denki Kabushiki Kaisha Apparatus for lighting alternating current discharge lamp
DE19733939A1 (de) * 1997-08-06 1999-02-11 Mannesmann Vdo Ag Schaltungsanordnung zum dimmbaren Betrieb einer Leuchtstofflampe
US5907222A (en) * 1993-11-03 1999-05-25 Litton Systems, Inc. High efficiency backlighting system for rear illumination of electronic display devices
GB2314430B (en) * 1996-06-19 2000-11-29 Kijima Co Ltd Inverter provided with output regulating mechanism
US6351080B1 (en) 1997-04-24 2002-02-26 Mannesmann Vdo Ag Circuitry for dimming a fluorescent lamp
DE10058551A1 (de) * 2000-11-24 2002-06-06 Bosch Gmbh Robert Vorrichtung mit einer Gasentladungslampe
DE10101275A1 (de) * 2001-01-12 2002-07-25 Vogt Electronic Ag Vorschaltgerät für Kaltkathoden-Fluoreszenzlampen
WO2004082339A1 (fr) * 2003-03-14 2004-09-23 Samsung Electronics Co., Ltd. Dispositif et methode de commande de source lumineuse pour affichage
DE4326415B4 (de) * 1993-08-06 2006-04-13 Siemens Ag Verfahren zur Ansteuerung einer Leuchtstofflampe und Anordnung zur Durchführung des Verfahrens

Families Citing this family (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0944168A (ja) * 1995-08-03 1997-02-14 Taisei Denki Kogyo:Kk 複数階建築物における床衝撃音消音装置
DE19535663A1 (de) * 1995-09-26 1997-03-27 Bosch Gmbh Robert Verfahren und Anordnung zur Leistungssteuerung einer Hochdruck-Gasentladungslampe
US5914613A (en) 1996-08-08 1999-06-22 Cascade Microtech, Inc. Membrane probing system with local contact scrub
US6256882B1 (en) 1998-07-14 2001-07-10 Cascade Microtech, Inc. Membrane probing system
US6914423B2 (en) 2000-09-05 2005-07-05 Cascade Microtech, Inc. Probe station
US6965226B2 (en) 2000-09-05 2005-11-15 Cascade Microtech, Inc. Chuck for holding a device under test
DE20114544U1 (de) 2000-12-04 2002-02-21 Cascade Microtech Inc Wafersonde
DE10319950A1 (de) * 2003-05-02 2004-11-18 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Betriebsgerät und Verfahren zum Betreiben von Gasentladungslampen
US7057404B2 (en) 2003-05-23 2006-06-06 Sharp Laboratories Of America, Inc. Shielded probe for testing a device under test
US7250626B2 (en) 2003-10-22 2007-07-31 Cascade Microtech, Inc. Probe testing structure
US7187188B2 (en) 2003-12-24 2007-03-06 Cascade Microtech, Inc. Chuck with integrated wafer support
DE202004021093U1 (de) 2003-12-24 2006-09-28 Cascade Microtech, Inc., Beaverton Aktiver Halbleiterscheibenmessfühler
US7420381B2 (en) 2004-09-13 2008-09-02 Cascade Microtech, Inc. Double sided probing structures
US7656172B2 (en) 2005-01-31 2010-02-02 Cascade Microtech, Inc. System for testing semiconductors
US7535247B2 (en) 2005-01-31 2009-05-19 Cascade Microtech, Inc. Interface for testing semiconductors
US7764072B2 (en) 2006-06-12 2010-07-27 Cascade Microtech, Inc. Differential signal probing system
US7723999B2 (en) 2006-06-12 2010-05-25 Cascade Microtech, Inc. Calibration structures for differential signal probing
US7403028B2 (en) 2006-06-12 2008-07-22 Cascade Microtech, Inc. Test structure and probe for differential signals
US7876114B2 (en) 2007-08-08 2011-01-25 Cascade Microtech, Inc. Differential waveguide probe
US7888957B2 (en) 2008-10-06 2011-02-15 Cascade Microtech, Inc. Probing apparatus with impedance optimized interface
WO2010059247A2 (fr) 2008-11-21 2010-05-27 Cascade Microtech, Inc. Coupon amovible pour appareil de sondage
US8319503B2 (en) 2008-11-24 2012-11-27 Cascade Microtech, Inc. Test apparatus for measuring a characteristic of a device under test

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2090082A (en) * 1980-12-19 1982-06-30 Gen Electric Fluorescent light unit with dual light levels
EP0164774A1 (fr) * 1984-05-14 1985-12-18 Philips Patentverwaltung GmbH Dispositif de circuit pour régler la tension de l'arc dans des lampes à décharge à haute pression
EP0349707A1 (fr) * 1988-07-06 1990-01-10 Wide-Lite International Corporation Circuit de ballast biniveau pour le fonctionnement de lampes de décharge à haute intensité

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2090082A (en) * 1980-12-19 1982-06-30 Gen Electric Fluorescent light unit with dual light levels
EP0164774A1 (fr) * 1984-05-14 1985-12-18 Philips Patentverwaltung GmbH Dispositif de circuit pour régler la tension de l'arc dans des lampes à décharge à haute pression
EP0349707A1 (fr) * 1988-07-06 1990-01-10 Wide-Lite International Corporation Circuit de ballast biniveau pour le fonctionnement de lampes de décharge à haute intensité

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2707054A1 (en) * 1993-06-21 1994-12-30 Valeo Vision DC converter for supplying an electric load, especially a fluorescent tube
DE4326415B4 (de) * 1993-08-06 2006-04-13 Siemens Ag Verfahren zur Ansteuerung einer Leuchtstofflampe und Anordnung zur Durchführung des Verfahrens
US5907222A (en) * 1993-11-03 1999-05-25 Litton Systems, Inc. High efficiency backlighting system for rear illumination of electronic display devices
US5705897A (en) * 1994-07-12 1998-01-06 Mitsubishi Denki Kabushiki Kaisha Apparatus for lighting alternating current discharge lamp
EP0804052A2 (fr) * 1996-04-24 1997-10-29 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Circuit de commande pour une lampe à décharge
EP0804052A3 (fr) * 1996-04-24 1999-04-07 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Circuit de commande pour une lampe à décharge
GB2314430B (en) * 1996-06-19 2000-11-29 Kijima Co Ltd Inverter provided with output regulating mechanism
US6351080B1 (en) 1997-04-24 2002-02-26 Mannesmann Vdo Ag Circuitry for dimming a fluorescent lamp
DE19733939A1 (de) * 1997-08-06 1999-02-11 Mannesmann Vdo Ag Schaltungsanordnung zum dimmbaren Betrieb einer Leuchtstofflampe
DE10058551A1 (de) * 2000-11-24 2002-06-06 Bosch Gmbh Robert Vorrichtung mit einer Gasentladungslampe
DE10101275A1 (de) * 2001-01-12 2002-07-25 Vogt Electronic Ag Vorschaltgerät für Kaltkathoden-Fluoreszenzlampen
DE10101275C2 (de) * 2001-01-12 2003-04-17 Vogt Electronic Ag Vorschaltgerät für Kaltkathoden-Fluoreszenzlampen
WO2004082339A1 (fr) * 2003-03-14 2004-09-23 Samsung Electronics Co., Ltd. Dispositif et methode de commande de source lumineuse pour affichage
US7446489B2 (en) 2003-03-14 2008-11-04 Samsung Electronics Co., Ltd. Apparatus and method of driving light source for display device

Also Published As

Publication number Publication date
KR920007495A (ko) 1992-04-28
JPH04133298A (ja) 1992-05-07
JP3196206B2 (ja) 2001-08-06
KR940004786B1 (ko) 1994-05-28

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