WO2005051051A2 - Method and apparatus for controlling visual enhancement of lighting devices - Google Patents
Method and apparatus for controlling visual enhancement of lighting devices Download PDFInfo
- Publication number
- WO2005051051A2 WO2005051051A2 PCT/US2004/037504 US2004037504W WO2005051051A2 WO 2005051051 A2 WO2005051051 A2 WO 2005051051A2 US 2004037504 W US2004037504 W US 2004037504W WO 2005051051 A2 WO2005051051 A2 WO 2005051051A2
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- luminent
- current
- control signal
- current control
- individual
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims abstract description 23
- 230000000007 visual effect Effects 0.000 title abstract description 36
- 238000005286 illumination Methods 0.000 claims abstract description 19
- 239000003990 capacitor Substances 0.000 claims description 11
- 238000012545 processing Methods 0.000 claims description 5
- 230000003287 optical effect Effects 0.000 claims description 4
- 230000004044 response Effects 0.000 claims description 2
- 238000001914 filtration Methods 0.000 claims 2
- 239000004973 liquid crystal related substance Substances 0.000 abstract description 5
- 238000003491 array Methods 0.000 description 4
- 238000013461 design Methods 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000004880 explosion Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
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
- H05B41/26—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc
- H05B41/28—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters
- H05B41/282—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters with semiconductor devices
-
- 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
- H05B41/26—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc
-
- 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
- H05B41/245—Circuit arrangements in which the lamp is fed by high frequency ac, or with separate oscillator frequency for a plurality of lamps
-
- 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
- H05B41/26—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc
- H05B41/28—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters
- H05B41/282—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters with semiconductor devices
- H05B41/2821—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters with semiconductor devices by means of a single-switch converter or a parallel push-pull converter in the final stage
- H05B41/2822—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters with semiconductor devices by means of a single-switch converter or a parallel push-pull converter in the final stage using specially adapted components in the load circuit, e.g. feed-back transformers, piezoelectric transformers; using specially adapted load circuit configurations
-
- 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
-
- 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
- H05B41/3922—Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor with possibility of light intensity variations and measurement of the incident light
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
Definitions
- the presently disclosed embodiments relate generally to the control of light emitting devices such as Cold Cathode Fluorescent Lamps and Light Emitting Diodes. More specifically, the disclosed embodiments relate to controlling the backlighting of Liquid Crystal Displays.
- CCFLs Cold Cathode Fluorescent Lamps
- LCDs Liquid Crystal Displays
- the CCFL has quickly been adopted for use as the backlight in notebook computers, and various portable electronic devices because it provides superior illumination and cost efficiency. These applications generally require uniformity of display brightness and illumination intensity.
- liquid crystal material separated from a CCFL backlighting device by a diffuser layer, polarizes the light for each display pixel.
- a high voltage DC/AC inverter is required to drive the CCFL because this lamp uses a high Alternating Current (AC) operating voltage.
- AC Alternating Current
- Intensity of illumination is determined by the operating current applied to the CCFL by an inverter.
- each lamp must be driven by its own costly inverter, or one shared inverter sets the operating current of all the lamps to a current determined by a preset amount of total current for all the lamps.
- each lamp varies in brightness and intensity due to age, replacement and inherent manufacturing variations. Applying the same reference current to each lamp, without adjusting for individual lamp variations, creates a different intensity of illumination for each lamp. Varying illumination intensities cause visible undiffused lines to be displayed.
- Conventional single inverter circuits cannot individually sense and adjust the operating current for each lamp in order to equalize the illumination intensity across multiple lamp array display panels.
- Conventional types of backlights for LCD devices are not fully satisfactory in illumination intensity uniformity.
- Embodiments disclosed herein address the above-stated needs by providing a method and apparatus for a visual enhancement control module having a single CCFL inverter capable of preserving individual current settings in multiple lamp arrays.
- the visual enhancement control module uses a switching circuit comprising a rectifier bridge, a transistor switch and a microcontroller interface serially coupled to a CCFL circuit. Alternatively a switched capacitor circuit is serially coupled to a CCFL circuit.
- a microprocessor executes servo control system software for sensing current and illumination intensity feedback information used to drive a current control circuit. The system software monitors the current and voltage across the lamps and determines the capacitance required to obtain a specific amount of current in each lamp.
- a visual enhancement control module comprising a single inverter drives a multiple lamp array while retaining precise control of current, and hence intensity of illumination, in each lamp.
- a method of current control for multiple luminent devices is disclosed. The method senses individual output information for each luminent device of a multiple device array and processes the output information to produce individual current control signals for each device that is used for adjusting an operating current applied to each device through a single inverter in accord with the current control signals.
- an apparatus for current control of multiple luminent devices includes sensors for sensing individual output information for each luminent device of a multiple device array, a microcontroller for processing the output information to produce individual current control signals for each device, and a current equalization circuit and server control system software for adjusting an operating current applied to each device through a single inverter in accordance with the current control signals.
- FIG. 1 shows a conventional inverter circuit for driving a single CCFL
- FIG. 2 illustrates conventional variations in characteristic current with respect to voltage for multiple CCFLs driven by conventional individual inverters
- FIG. 3 illustrates conventional variations in characteristic current with respect to voltage for multiple CCFLs driven by a conventional shared inverter
- FIG. 4 illustrates a visual enhancement closed loop control system for multiple CCFLs in accordance with one embodiment of the present invention
- FIG. 5 illustrates a visual enhancement control system for multiple CCFLs in accordance with another embodiment of the present invention
- FIG. 6 shows a visual enhancement control module in accordance with one embodiment of the present invention.
- FIG. 7 shows a visual enhancement control module in accordance with another embodiment of the present invention.
- the disclosed embodiments provide a method and apparatus for visual enhancement of liquid crystal displays.
- a microprocessor or embedded microcontroller associated with visual enhancement circuit modules allows a single inverter to control the intensity of illumination for an array of multiple CCFLs.
- the microcontroller continuously senses the operating currents of every lamp and adjusts for variations in illumination of individual lamps by parallel switching of capacitance that ensures an equal current is applied to each lamp.
- the microcontroller produces the appropriate control signals and executes a digital servo control algorithm to modify the currents for carrying out the luminance adjustments.
- FIG. 1 illustrates a conventional CCFL control circuit 100 requiring an inverter 120 for each lamp 104 in an LCD backlight array.
- Fluorescent lamps 104 exhibit significant manufacturing variations.
- Lamps 104 are driven from an inverter control circuit 120, which contains a primary side circuit 106, and a secondary side circuit 108.
- the primary side circuit 106 manages high currents and low voltages and connects to the primary side of a transformer 110.
- the secondary side circuit 108 connects to the secondary of the transformer 112, a ballast capacitor 114, the fluorescent lamp 104, a current sensor 116 and a potentiometer 118 to adjust the lamp current.
- FIG. 2 variations in characteristic current with respect to voltage 200 for multiple CCFLs driven by the conventional control circuit illustrated in FIG. 1 are graphically shown.
- Each lamp requires a strike voltage (201, 202) to ionize the contained gas of the lamp and achieve a luminous output. After the lamp strikes, each lamp will exhibit a different voltage-current relationship as shown by their operating voltage slopes (203, 204).
- FIG. 3 shows conventional variations in characteristic current with respect to voltage when two CCFLs are driven from the same inverter. Each slope (305, 306) is different after its strike voltage has been attained. If a target lamp current equals a Nominal Operating Current of IOP 301, and the Nominal Sustaining Voltage equals VSUS 302, the voltage applied to lamp 1 must be reduced by a delta of V1 to obtain a voltage across lamp 1 of VSUS minus the delta of V1 303. Likewise, the voltage applied to Lamp 2 voltage must be reduced by a delta of V2 to obtain a voltage across lamp 2 of VSUS minus the delta of V2 304. The voltage reductions across the lamps will result in the same Nominal Operating Current of IOP for both lamps, which will produce a uniform intensity of illumination.
- FIG. 4 is a block diagram illustrating a novel visual enhancement closed loop control system 400 for backlighting an array of N CCFLs 401 in accordance with one embodiment of the present invention.
- a microcontroller 402 executes, from non-volatile memory, one or more software modules comprising program instructions that generate current control signals 402 for input to a Field Programmable Gate Array (FPGA) 406.
- a software module may reside in the microcontroller, RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.
- the FPGA 406 distributes the current control signals 402 to visual enhancement control modules 408 associated with individual CCFLs 401 as specified by the microcontroller 402.
- the visual enhancement control modules 408 (detailed in FIG.
- a servo control algorithm software module executed by the microcontroller 402 continuously utilizes the multiplexed feedback information provided by the current sensors 410 to adjust visual enhancement control module 408 settings. These setting adjustments maintain desired individual lamp currents by continuously compensating for current variations caused by age, replacement, inherent manufacturing variations and changes in temperature.
- Software modules executed by the microcontroller 402 concurrently control and adjust the operation of an inverter 414 that controls the secondary voltage output of the inverter 414 (See FIG. 1 , element 112).
- the secondary voltage output of the inverter is applied to the CCFLs 401.
- any combination of microcontrollers 402, inverters 414, memory, FPGAs 406, multiplexers 412, current sensors 410 and control modules 408 may be integrated on a Printed Circuit (PC) board or in an Application Specific Integrated Circuit (ASIC).
- the microcontroller 402, FPGA 406 and Multiplexer 412 may be integrated with the inverter assembly 414.
- the microcontroller 402, FPGA 406 functionally and the multiplexer 412 may also be integrated in the same, or another, single Integrated Circuit (IC).
- one or more visual enhancement control modules 408 may be integrated in a single IC, which may also comprise current sensors 410 or light sensors (See FIG. 5, element 510) .
- FIG. 5 illustrates a visual enhancement control system for multiple CCFLs in accordance with another embodiment of the present invention.
- the alternative visual enhancement control system 500 embodied in FIG. 5 utilizes one or more light sensors 510 rather than current sensors (See FIG. 4, element 410) to provide feedback information to the microcontroller 502.
- a servo control algorithm software module executed by the microcontroller 502 continuously utilizes multiplexed feedback information provided by the light sensors 510 to adjust the visual enhancement control module settings. These setting adjustments maintain desired individual levels of luminance by continuously compensating for variations caused by age, replacement, inherent manufacturing variations and changes in temperature.
- visual enhancement control modules 508 set the current in the CCFLs 501.
- the amount of current applied to each CCFL 501 through its associated visual enhancement control module 508 is determined by control signals from logic block 506.
- Logic block 506 performs the equivalent functionality of a FPGA (See FIG 4., element 404.)
- the logic block 506, the microcontroller 502 and the analog multiplexer 512 may be components of a single integrated digital controller circuit.
- Feedback to the visual enhancement closed loop control system 500 is provided by one or more light sensors 510.
- the light sensors 510 detect the amount of light output by the CCFLs 501.
- the light sensors 510 produce light output feedback signals for input to an analog multiplexer 512.
- the analog multiplexer 512 routes the light sensor feedback signals to an analog to digital (A/D) converter, which may be embedded in the microcontroller 502.
- a closed loop servo control algorithm software module executed by the microcontroller 502 continuously maintains a predetermined luminance set point for each CCFL 501. As CCFLs 501 age, output precision is advantageously improved by determining luminance output levels with light sensors 510.
- a visual enhancement control system may also operate to produce visual effects in backlit luminent devices.
- the visual enhancement control system may be used to increase or decrease luminosity in selected portions of a display. For example, three dimensional effects can be created for video material comprising an explosion by increasing the light output level of portions of the display where the explosion occurs. Similarly, visual effects can be created for material enhanced by shadows such as scenes of a dark alleyway. Visual effects can be created by the disclosed control system using software modules that vary the amount of light output from a backlighting device in specific areas of a display.
- FIG. 6 details the visual enhancement control modules illustrated in the system block diagrams of FIG.
- the visual enhancement control module 600 adjusts the current applied to an individual CCFL according to control signals externally generated by a microcontroller (not shown).
- Inputs 1 602 and 2 604 receive a current control signal routed from a microcontroller by a system controller FPGA or Logic Block (not shown).
- the control signal may comprise a Direct Current (DC) voltage, or a Pulse Width Modulated (PWM) signal.
- the value of the control signal determines the amount of current through each CCFL in a multiple lamp array.
- the control signals are applied to U1 606, an optical or photovoltaic device for converting the control signal to an isolated control voltage.
- Resistors R2 612 and R3 614 set a specified current in U1 606 proportional to the applied control signal.
- An optical isolator transfers the control signal to a secondary side of U1 610.
- U1 is a photovoltaic inverter
- light produced by output LEDs 626 in U1 will be converted to a voltage by the secondary side of U1 610.
- Capacitor C1 618 filters the output of U1 to produce an isolated control signal compatible with transistor Q1 622.
- Resistor R1 620 sets the impedance at the base of Q1 622 to a value that enables stable operation of Q1 622.
- Transistor Q1 622 may operate in a switch mode or in a linear mode as required by the CCFL current response.
- a current control bridge comprised of diodes D1-D4 624 routes both polarities of Alternating Current (AC) through Q1 622 to drive the CCFL.
- AC Alternating Current
- FIG. 7 details the visual enhancement control modules illustrated in the system block diagrams of FIG. 4 and FIG 5. in accordance with another embodiment of the present invention.
- the visual enhancement control module 700 comprises a current control circuit 704 for CCFL1 701 and a current control circuit 705 for CCFL 2 702.
- the control circuits (704,705) are comprised of a plurality of parallel capacitors 708 coupled by switches 710.
- a microprocessor 706 controls inverter 703. Other values of capacitors 708 may be used to vary the current control effect.
- the disclosed visual enhancement control system using the disclosed visual control enhancement modules provides a CCFL control circuit that is highly optimized in cost and performance. All CCFLs in an array can be made to exhibit equal (or a specified) luminance and current while driven by the same inverter. [1046]
- One skilled in the art will understand that the ordering of steps and components illustrated in the figures above is not limiting. The methods and components are readily amended by omission or re-ordering of the steps and components illustrated without departing from the scope of the disclosed embodiments.
- DSP digital signal processor
- ASIC application specific integrated circuit
- FPGA field programmable gate array
- a general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine.
- a processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.
- the steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two.
- a software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD- ROM, or any other form of storage medium known in the art.
- An exemplary storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium.
- the storage medium may be integral to the processor.
- the processor and the storage medium may reside in an ASIC.
- the processor and the storage medium may reside as discrete components.
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Circuit Arrangements For Discharge Lamps (AREA)
- Circuit Arrangement For Electric Light Sources In General (AREA)
- Control Of Indicators Other Than Cathode Ray Tubes (AREA)
- Discharge-Lamp Control Circuits And Pulse- Feed Circuits (AREA)
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2006539807A JP2007511062A (en) | 2003-11-06 | 2004-11-08 | Method and apparatus for visual enhancement control of light emitting devices |
KR1020067010485A KR100888782B1 (en) | 2003-11-06 | 2004-11-08 | Method and apparatus for controlling visual enhancement of luminent devices |
EP04819080A EP1683397A2 (en) | 2003-11-06 | 2004-11-08 | Method and apparatus for controlling visual enhancement of lighting devices |
US11/400,491 US20060181228A1 (en) | 2004-02-06 | 2006-04-07 | Device for controlling drive current for an electroluminescent device array with amplitude shift modulation |
US11/693,240 US20070222400A1 (en) | 2003-11-06 | 2007-03-29 | Method and apparatus for equalizing current in a fluorescent lamp array |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US51849003P | 2003-11-06 | 2003-11-06 | |
US60/518,490 | 2003-11-06 | ||
PCT/US2004/003400 WO2004072733A2 (en) | 2003-02-06 | 2004-02-06 | Digital control system for lcd backlights |
USPCT/US2004/003400 | 2004-02-06 |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/400,491 Continuation US20060181228A1 (en) | 2003-11-06 | 2006-04-07 | Device for controlling drive current for an electroluminescent device array with amplitude shift modulation |
Publications (2)
Publication Number | Publication Date |
---|---|
WO2005051051A2 true WO2005051051A2 (en) | 2005-06-02 |
WO2005051051A3 WO2005051051A3 (en) | 2005-09-15 |
Family
ID=34619324
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2004/037504 WO2005051051A2 (en) | 2003-11-06 | 2004-11-08 | Method and apparatus for controlling visual enhancement of lighting devices |
Country Status (5)
Country | Link |
---|---|
EP (1) | EP1683397A2 (en) |
JP (1) | JP2007511062A (en) |
KR (1) | KR100888782B1 (en) |
CN (1) | CN1899000A (en) |
WO (1) | WO2005051051A2 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2006011101A1 (en) * | 2004-07-21 | 2006-02-02 | Koninklijke Philips Electronics N.V. | Uniform back-lighting device and display device therewith |
JP2007250230A (en) * | 2006-03-14 | 2007-09-27 | Sumida Corporation | Cold-cathode tube driving device |
CN100414383C (en) * | 2005-08-16 | 2008-08-27 | 明基电通股份有限公司 | Apparatus for lighting up multiple luminous tubes |
US8836235B2 (en) | 2010-06-25 | 2014-09-16 | Planet System Co., Ltd. | Apparatus for automatically controlling the illumination of LED lighting |
US11567551B2 (en) | 2020-07-28 | 2023-01-31 | Rohde & Schwarz Gmbh & Co. Kg | Adaptive power supply |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100779348B1 (en) * | 2007-08-10 | 2007-11-23 | 여운남 | Apparatus and method for controlling dimming |
KR101053349B1 (en) * | 2009-02-24 | 2011-08-01 | 삼성전기주식회사 | Power supply for driving lamps with current balancing |
MX2014004566A (en) * | 2011-10-18 | 2014-07-09 | Raqualia Pharma Inc | Medicinal composition. |
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EP1077444A2 (en) * | 1999-08-11 | 2001-02-21 | Agilent Technologies Inc | System and method for on-chip calibration of illumination sources for an integrated circuit display |
US20020097004A1 (en) * | 2001-01-19 | 2002-07-25 | Yi-Chao Chiang | Power supply system for multiple loads and driving system for multiple lamps |
US20040004450A1 (en) * | 2002-06-26 | 2004-01-08 | Darfon Electronics Corp. | Multiple-lamp backlight inverter |
WO2004026006A2 (en) * | 2002-08-28 | 2004-03-25 | Harman/Becker Automotive Systems Gmbh | Control system for light tubes |
US20040068511A1 (en) * | 2000-11-28 | 2004-04-08 | Jorge Sanchez Olea | Software enabled control for systems with luminent devices |
WO2004072733A2 (en) * | 2003-02-06 | 2004-08-26 | Ceyx Technologies, Inc. | Digital control system for lcd backlights |
US20040207340A1 (en) * | 2003-04-11 | 2004-10-21 | Benq Corporation | Device and method for adjusting currents of lamp tubes |
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KR100840933B1 (en) * | 2002-01-31 | 2008-06-24 | 삼성전자주식회사 | Apparatus for driving lamp and liquid crystal display with the same |
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2004
- 2004-11-08 KR KR1020067010485A patent/KR100888782B1/en active IP Right Grant
- 2004-11-08 CN CNA2004800380378A patent/CN1899000A/en active Pending
- 2004-11-08 JP JP2006539807A patent/JP2007511062A/en active Pending
- 2004-11-08 EP EP04819080A patent/EP1683397A2/en not_active Withdrawn
- 2004-11-08 WO PCT/US2004/037504 patent/WO2005051051A2/en active Application Filing
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EP1077444A2 (en) * | 1999-08-11 | 2001-02-21 | Agilent Technologies Inc | System and method for on-chip calibration of illumination sources for an integrated circuit display |
US20040068511A1 (en) * | 2000-11-28 | 2004-04-08 | Jorge Sanchez Olea | Software enabled control for systems with luminent devices |
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Title |
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Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2006011101A1 (en) * | 2004-07-21 | 2006-02-02 | Koninklijke Philips Electronics N.V. | Uniform back-lighting device and display device therewith |
CN100414383C (en) * | 2005-08-16 | 2008-08-27 | 明基电通股份有限公司 | Apparatus for lighting up multiple luminous tubes |
JP2007250230A (en) * | 2006-03-14 | 2007-09-27 | Sumida Corporation | Cold-cathode tube driving device |
US8836235B2 (en) | 2010-06-25 | 2014-09-16 | Planet System Co., Ltd. | Apparatus for automatically controlling the illumination of LED lighting |
US11567551B2 (en) | 2020-07-28 | 2023-01-31 | Rohde & Schwarz Gmbh & Co. Kg | Adaptive power supply |
Also Published As
Publication number | Publication date |
---|---|
KR100888782B1 (en) | 2009-03-16 |
KR20060086447A (en) | 2006-07-31 |
WO2005051051A3 (en) | 2005-09-15 |
EP1683397A2 (en) | 2006-07-26 |
CN1899000A (en) | 2007-01-17 |
JP2007511062A (en) | 2007-04-26 |
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