WO2005008196A2 - Method and device for measuring color temperature - Google Patents
Method and device for measuring color temperature Download PDFInfo
- Publication number
- WO2005008196A2 WO2005008196A2 PCT/IB2004/051196 IB2004051196W WO2005008196A2 WO 2005008196 A2 WO2005008196 A2 WO 2005008196A2 IB 2004051196 W IB2004051196 W IB 2004051196W WO 2005008196 A2 WO2005008196 A2 WO 2005008196A2
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- sensor
- measuring
- color temperature
- sensor assembly
- signal
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims abstract description 16
- 230000003595 spectral effect Effects 0.000 claims abstract description 8
- 230000035945 sensitivity Effects 0.000 claims description 10
- 238000001228 spectrum Methods 0.000 claims description 4
- 230000001419 dependent effect Effects 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 7
- 230000006870 function Effects 0.000 description 6
- 238000007796 conventional method Methods 0.000 description 3
- 238000013461 design Methods 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000004590 computer program Methods 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 238000013095 identification testing Methods 0.000 description 1
- 229910001507 metal halide Inorganic materials 0.000 description 1
- 150000005309 metal halides Chemical class 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D3/00—Indicating or recording apparatus with provision for the special purposes referred to in the subgroups
- G01D3/02—Indicating or recording apparatus with provision for the special purposes referred to in the subgroups with provision for altering or correcting the law of variation
- G01D3/024—Indicating or recording apparatus with provision for the special purposes referred to in the subgroups with provision for altering or correcting the law of variation for range change; Arrangements for substituting one sensing member by another
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J1/00—Photometry, e.g. photographic exposure meter
- G01J1/10—Photometry, e.g. photographic exposure meter by comparison with reference light or electric value provisionally void
- G01J1/12—Photometry, e.g. photographic exposure meter by comparison with reference light or electric value provisionally void using wholly visual means
- G01J1/14—Photometry, e.g. photographic exposure meter by comparison with reference light or electric value provisionally void using wholly visual means using comparison with a surface of graded brightness
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J1/00—Photometry, e.g. photographic exposure meter
- G01J1/42—Photometry, e.g. photographic exposure meter using electric radiation detectors
- G01J1/4257—Photometry, e.g. photographic exposure meter using electric radiation detectors applied to monitoring the characteristics of a beam, e.g. laser beam, headlamp beam
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
- G01J5/60—Radiation pyrometry, e.g. infrared or optical thermometry using determination of colour temperature
Definitions
- the present invention relates in general to a method and device for measuring the color temperature of a light source.
- the present invention relates to a driver device for driving a light source having variable color temperature.
- a conventional method of measuring color temperature comprises the step of first measuring the color point, and then calculating the closest point on the black body line.
- a first disadvantage of such conventional method is the relative complexity of such calculation.
- a direct way of measuring the three coordinates x, y and z involves actually measuring the three corresponding intensities, which involves the use of three color sensors, each including a corresponding color filter and a light intensity detector. Such color sensors are relatively expensive.
- An example of a method and device according to this principle is disclosed in
- a main objective of the present invention is to provide a more economic way of measuring the color temperature of a light source.
- the present invention relates to a driver device for a gas discharge lamp, specifically a HID lamp, more specifically a metal halide lamp.
- Typical lamp drivers comprise a stage generating a substantially constant current, followed by a commutator for commutating the lamp current, i.e. regularly changing the direction of the current in the lamp.
- commutator operates at a duty cycle of 50%, i.e. in each current period, the duration of the current flow from one electrode to the other is equal to the duration of the current flow in the opposite direction.
- the present applicant has described a gas discharge lamp with variable color properties.
- the color temperature is varied over a wide temperature range; depending on the composition of the lamp filling, the temperature range may extend from about 2500 K to about 6000 K.
- the present invention relates to the aspect of transferring two measuring signals to a processing circuit. Normally, this requires three wires: one wire for each measuring signal, and a common ground wire. Each wire involves costs of wiring and associated connectors. Further, with each wire, assembly complexity and assembly time increase. It is a further objective of the present invention to reduce this problem.
- a method for measuring a color temperature, wherein the absolute intensity of one predefined blue spectral component B as well as the overall light intensity or luminance V are measured, and the quotient B/V is calculated.
- This method which is based on the insight that said quotient B/V appears to have an almost linear relationship to the color temperature, involves only one relatively expensive color sensor and one relatively inexpensive luminance sensor (i.e. a light intensity sensor).
- a further advantage of this method is the fact that the overall light intensity, which is typically an important parameter of interest, is also directly made available; in the conventional method, the overall light intensity must be determined indirectly, or, if it is to be determined directly, a further detector is required.
- a driver for a light source comprising a sensor assembly for generating a measuring signal indicating the color temperature, which measuring signal is fed back to a controller of the driver, which is designed to adapt its settings such as to keep the color temperature substantially constant.
- this sensor assembly comprises a blue sensor and a luminance sensor, allowing the controller to determine the ratio B/V.
- a sensor assembly comprising two sensor diodes is provided, each sensor diode being connected in series with a corresponding auxiliary diode in an opposite direction, these two series arrangements being connected anti-parallel to each other. When a supply voltage having a first polarity is applied to this assembly, a current is generated indicating the measuring signal of a first sensor diode. When the supply voltage has opposite polarity, the current indicates the measuring signal of the other sensor diode.
- Fig. 1 is a block diagram, schematically showing a driver device according to the present invention
- Fig. 2 is a graph schematically illustrating lamp current as a function of time
- Fig. 3 is a graph schematically illustrating color temperature as a function of duty cycle
- Fig. 4 is a block diagram schematically illustrating a preferred embodiment of some components of a lamp driver
- Fig. 5 is a graph schematically illustrating a relationship between B/V and color temperature
- Fig. 6 is a block diagram schematically illustrating a preferred embodiment of some components of a lamp driver.
- Fig. 1 is a block diagram schematically illustrating a preferred embodiment of a driver device or electronic ballast 10 according to the invention for driving a gas discharge lamp 2 in a lamp system 1 with variable color properties.
- the ballast 10 typically comprises: an input 11 for receiving AC mains; a rectifier 12 for rectifying the AC mains voltage to a rectified DC voltage; a DC/DC up-converter 13 for converting the rectified mains DC voltage to a higher DC voltage and for performing power factor correction; a down-converter 14 for converting said higher DC voltage to a lower DC voltage (lamp voltage) and a corresponding DC current (lamp current); and a commutator 15 for regularly changing the direction of this DC current within a very brief time (commutating periods).
- the ballast may have a different design.
- the down converter behaves as a current source.
- the commutator operates at a frequency in the order of about 50 - 400 Hz. Therefore, in principle, the lamp is operated at constant current magnitude, the lamp current regularly changing its direction within a very brief time (commutating periods), i.e. an electrode is operated as a cathode in a first part of each current period and is operated as anode during the remainder of each current period.
- Fig. 2 is a graph schematically illustrating the current II through the lamp 2 as a function of time.
- the lamp current II has constant magnitude but changing direction.
- an average current IAV may be defined as (t ⁇ -t 2 )l ⁇ /P.
- a driver is designed such that its output may be considered as constituting a current source with alternating current direction but constant current magnitude, having a duty cycle of 50%; in that case, the average current IAV is zero.
- HID lamps have a property that the color temperature Tc is variable as a function of the average current IAV > which can be varied by varying the duty cycle D, as explained more elaborately in PCT/IB03/01547, incorporated herein by reference.
- the driver 10 is capable of driving the lamp 2 with variable average lamp current IAV-
- the average current IAV differs from zero because the current intensity during the positive current period differs from the current intensity during the negative current period, in which case the current may have a duty cycle of 50%.
- the duty cycle differs from 50% and the current intensity remains constant at all times, i.e. the lamp current magnitude during the "positive" half of a current period (ti) is equal to the current magnitude during the "negative” half of the current period (t 2 ) (see Fig. 2)
- the driver 10 is designed to have an adaptable duty cycle.
- the relationship between the color temperature Tc and the duty cycle D is as depicted in Fig. 3, where the horizontal axis represents the duty cycle and the vertical axis represents the color temperature. The exact values of the color temperature depend on the precise composition of the lamp filling. It has been found that the relationship between D and Tc is not constant over the life time of the lamp.
- the driver 10 comprises a light sensor assembly 20, arranged in the proximity of the lamp 2, for receiving light from the lamp 2 and generating a sensor signal S(Tc) which contains information regarding the color temperature of the lamp light.
- the driver 10 further comprises a controller 50, which has a measuring input 51 and a first control output 52.
- the sensor assembly 20 is coupled to the measuring input 51 of the controller 50.
- the controller 50 is adapted for generating, at its first control output 52, a commutator control signal So for controlling the commutator 15, more particularly for controlling its duty cycle D, on the basis of the sensor signal S(Tc), such as to keep the sensor signal S(Tc) and hence the lamp color temperature constant.
- the lamp driver may be designed for one specific color temperature setting in association with one specific lamp type, but typically the lamp driver will allow a user to set a specific color temperature.
- the controller 50 has a first user input 54 for receiving a first user control signal Siji as a user-generated color setting signal.
- the driver 10 further comprises a control setting device 57, such as for instance a potentiometer, generating the first user control signal STJI which can be varied continuously within a predetermined range.
- the control setting device 57 can be user-controllable, but it can also be a suitably programmed controller.
- the controller 50 is also provided with a dimming facility, i.e. a facility for setting the intensity of the light generated by the lamp 2.
- the controller 50 has a second user input 55 and a second control output 53.
- the controller 50 receives a second user control signal S ⁇ 2 as a user- generated intensity setting signal.
- the driver 10 further comprises an intensity setting device 58, such as for instance a potentiometer, generating the second user control signal S 2 which can be varied continuously within a predetermined range.
- the intensity setting device 58 can be user-controllable, but it can also be a suitably programmed controller.
- the controller 50 At its second control output 53, the controller 50 generates an intensity control signal Si for the down- converter 14 to control the magnitude of the lamp current I ⁇ _.
- the controller 50 may be designed to generate its intensity control signal Si on the basis of the actual second user input signal S ⁇ j 2 only. Preferably, however, in a control mode, the controller keeps the light intensity constant on the basis of the measuring signal from the sensor assembly 20.
- blue light will be understood as light having a wavelength in the range of approximately 380 nm to approximately 480 nm.
- the blue sensor 22 is sensitive to substantially the entire blue range. It is noted that it is not necessary that the blue sensor 22 has equal sensitivity for all wavelengths within its sensitivity range; usually, a sensor has a peak sensitivity at one wavelength, and a decreasing sensitivity with increasing distance from this one wavelength, as will be clear to a person skilled in the art.
- the blue sensor 22 may have a narrow sensitivity range around any wavelength within the blue range.
- the blue sensor 22 has a peak sensitivity in the order of about 440 nm.
- the measuring input 51 of the controller 50 actually comprises two input terminals 51a and 51b, the first one for receiving the luminance signal Sy and the second for receiving the blue signal SB-
- the luminance signal Sy can be used in a simple straightforward way for controlling the light intensity.
- the controller 50 comprises a first comparator 60, having one input receiving the luminance signal Sy and having another input receiving a reference light intensity signal REF ⁇ .
- This reference light intensity signal may be the user input signal received at the user input 55, or a reference value stored in a memory 56.
- the comparator output signal is coupled to the second control output 53 of the controller 50.
- the controller 50 is provided with a commutating switch stage 90 having input terminals 91a and 91b and an output terminal 99.
- This stage 90 is shown as an external stage, having its output terminal 99 connected to an input terminal 51 of the controller 50, but the stage 90 and the controller 50 may be one integrated unit, as should be clear to a person skilled in the art.
- the switch stage 90 comprises three switches 82, 83, 84.
- Each switch (82) [83] ⁇ 84 ⁇ has a central switch terminal (82c) [83c] ⁇ 84c ⁇ , a first switch terminal (82a) [83a] ⁇ 84a ⁇ , and a second switch terminal (82b) [83b] ⁇ 84b ⁇ .
- the first sensor diode 21 generates a sensor current on the basis of the amount of light received by the first sensor diode 21, which current flows into the second measuring resistor R2, developing a voltage over this second resistor R2. This voltage is provided at output terminal 99 as output signal, reflecting the measuring signal from the first sensor diode 21. In the second operative state, the situation is opposite, and the voltage developed over the first measuring resistor Rl, reflecting the measuring signal from the second sensor diode 22, is provided as output signal at output terminal 99.
- the controller 50 controls the switch stage 90 to regularly switch from the first operative state to the second and vice versa.
- the controller 50 knows which signal is which, for instance because the controller 50 is adapted to control the lamp current intensity to control the overall light intensity, as illustrated in Fig. 4, the values of the measuring resistors Rl and R2 may be chosen such that Sy is always larger than SB, or vice versa, in which case the relative magnitudes of the first and second measuring signals give the controller 50 the required information regarding which signal is which.
- selecting the resistance values of the measuring resistors Rl and R2 requires, however, knowledge on the characteristics of the sensors. It is also possible that the controller 50 is designed for performing a sensor identification test.
- Such a test involves the step of deliberately changing the driver settings (briefly) such that the relative amount of blue light is increased (or decreased); for instance, the driver settings may be set to values of which it is known that the relative amount of blue light is maximal (or minimal).
- the controller 50 can determine which sensor is the blue sensor.
- the present invention is not limited to the exemplary embodiments discussed above, but that several variations and modifications are possible within the protective scope of the invention as defined in the appending claims.
- the present invention is not applicable only to gas discharge lamps, or HID lamps. In other types of light sources, it may also be possible to achieve a variation of the color temperature by varying a control parameter (e.g. TL lamps).
- a driver for controlling the light source on the basis of a measuring signal indicating B/V is also useful.
- the sensor assembly and two-wire connection as proposed by the present invention are also useful.
- the controller 50 may be provided with a look-up table or a formula, based on the results of a measurement like shown in Fig. 5, so that the controller 50 is capable of retrieving or calculating Tc once the ratio B/V is determined. Further, in stead of using blue light, it is possible to use light from a different wavelength range within the visible range.
- a red range is mentioned, i.e. the range from approximately 610 nm to approximately 760 nm.
- the sensors are photo diodes sensitive to light.
- the measuring principle involved in the sensor assembly is not limited to diodes: other types of light-sensitive devices may be used also, such as for instance light-dependent resistors (LDRs).
- LDRs light-dependent resistors
- the measuring principle involved in the sensor assembly is even not limited to measuring light: the design of the sensor assembly can be applied using any type of sensor, sensitive to a certain parameter such that at least one electrical characteristic, e.g.
- the sensor assembly comprises a series connection of a diode with such sensor: as a result, a measuring signal (current) is only generated when a voltage having the correct polarity is applied across this series connection; in the case of opposite polarity, the series diode will block any measuring signal from its associated sensor.
- the sensor assembly further comprises a second series connection of a second diode with a second sensor (which need not necessarily be of the same type as the first sensor: the parameters to be measured may be quite different). The second series connection is connected anti-parallel to the first series connection, as far as the directions of the diodes is concerned. Further, with reference to Fig.
- the switch stage 90 is explained in relation to positive supply voltage Vcc and ground. However, it is also possible to use a negative reference voltage. Also, the measuring resistance may be connected in series with the reference voltage instead of the ground terminal.
- block diagrams which illustrate functional blocks of the device according to the present invention. It is to be understood that one or more of these functional blocks may be implemented in hardware, where the function of such functional block is performed by individual hardware components, but it is also possible that one or more of these functional blocks are implemented in software, so that the function of such functional block is performed by one or more program lines of a computer program or a programmable device such as a microprocessor, microcontroller, digital signal processor, etc..
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Engineering & Computer Science (AREA)
- Technology Law (AREA)
- Optics & Photonics (AREA)
- Circuit Arrangement For Electric Light Sources In General (AREA)
- Radiation Pyrometers (AREA)
- Spectrometry And Color Measurement (AREA)
- Circuit Arrangements For Discharge Lamps (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/565,144 US20060202641A1 (en) | 2004-07-12 | 2004-07-12 | Method and device for measuring color temperature |
JP2006520948A JP2006528346A (en) | 2003-07-22 | 2004-07-12 | Method and apparatus for measuring color temperature |
EP04744555A EP1660850A2 (en) | 2003-07-22 | 2004-07-12 | Method and device for measuring color temperature |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP03102249.4 | 2003-07-22 | ||
EP03102249 | 2003-07-22 |
Publications (2)
Publication Number | Publication Date |
---|---|
WO2005008196A2 true WO2005008196A2 (en) | 2005-01-27 |
WO2005008196A3 WO2005008196A3 (en) | 2005-05-12 |
Family
ID=34072670
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/IB2004/051196 WO2005008196A2 (en) | 2003-07-22 | 2004-07-12 | Method and device for measuring color temperature |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP1660850A2 (en) |
JP (1) | JP2006528346A (en) |
CN (1) | CN1826513A (en) |
WO (1) | WO2005008196A2 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006339149A (en) * | 2005-05-31 | 2006-12-14 | Koninkl Philips Electronics Nv | Apparatus and method of high-speed charging for charging capacitor |
EP2112533A1 (en) * | 2008-04-23 | 2009-10-28 | Chromasens GmbH | LED line lighting |
US7678422B2 (en) | 2006-12-13 | 2010-03-16 | Air Products And Chemicals, Inc. | Cyclic chemical vapor deposition of metal-silicon containing films |
US8022631B2 (en) | 2008-11-03 | 2011-09-20 | General Electric Company | Color control of light sources employing phosphors |
WO2014108598A1 (en) * | 2013-01-11 | 2014-07-17 | Nokia Corporation | Sensor array with fixed output |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101674689B (en) * | 2008-09-11 | 2013-01-30 | 谢婉毓 | Color temperature controller of light-emitting diodes (LED) and color temperature controlling method thereof |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0405674A1 (en) | 1989-06-30 | 1991-01-02 | Koninklijke Philips Electronics N.V. | Switching arrangement |
DE4421919A1 (en) | 1994-06-24 | 1996-01-04 | Karl Gerhard | Colour temp. constancy checking appts. for light source e.g. commercial or laboratory fluorescent lamp |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4039824A (en) * | 1974-08-08 | 1977-08-02 | Minolta Camera Kabushiki Kaisha | Focus detecting photoelectric device |
US4222663A (en) * | 1977-08-01 | 1980-09-16 | United Technologies Corporation | Optical pyrometer and technique for temperature measurement |
US4758734A (en) * | 1984-03-13 | 1988-07-19 | Nec Corporation | High resolution image sensor array using amorphous photo-diodes |
DE4013422C2 (en) * | 1990-04-26 | 2000-02-03 | Roland Man Druckmasch | Illumination device for a three-area color measuring device |
US5302883A (en) * | 1992-10-23 | 1994-04-12 | Industrial Technology Research Institute | Automated apparatus and method for the reproduction of same color temperature luminous intensity standard light source |
JPH06351038A (en) * | 1993-06-10 | 1994-12-22 | Matsushita Electric Ind Co Ltd | Auto-white balance device |
US5581077A (en) * | 1994-07-05 | 1996-12-03 | Lucent Technologies Inc. | Optical receiver with a high impedance preamplifier |
-
2004
- 2004-07-12 JP JP2006520948A patent/JP2006528346A/en active Pending
- 2004-07-12 WO PCT/IB2004/051196 patent/WO2005008196A2/en active Application Filing
- 2004-07-12 EP EP04744555A patent/EP1660850A2/en not_active Withdrawn
- 2004-07-12 CN CNA2004800210343A patent/CN1826513A/en active Pending
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0405674A1 (en) | 1989-06-30 | 1991-01-02 | Koninklijke Philips Electronics N.V. | Switching arrangement |
DE4421919A1 (en) | 1994-06-24 | 1996-01-04 | Karl Gerhard | Colour temp. constancy checking appts. for light source e.g. commercial or laboratory fluorescent lamp |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006339149A (en) * | 2005-05-31 | 2006-12-14 | Koninkl Philips Electronics Nv | Apparatus and method of high-speed charging for charging capacitor |
US7678422B2 (en) | 2006-12-13 | 2010-03-16 | Air Products And Chemicals, Inc. | Cyclic chemical vapor deposition of metal-silicon containing films |
EP2112533A1 (en) * | 2008-04-23 | 2009-10-28 | Chromasens GmbH | LED line lighting |
US8022631B2 (en) | 2008-11-03 | 2011-09-20 | General Electric Company | Color control of light sources employing phosphors |
WO2014108598A1 (en) * | 2013-01-11 | 2014-07-17 | Nokia Corporation | Sensor array with fixed output |
US8823396B2 (en) | 2013-01-11 | 2014-09-02 | Nokia Corporation | Apparatus and associated methods |
CN104903732A (en) * | 2013-01-11 | 2015-09-09 | 诺基亚技术有限公司 | Sensor array with fixed output |
Also Published As
Publication number | Publication date |
---|---|
EP1660850A2 (en) | 2006-05-31 |
WO2005008196A3 (en) | 2005-05-12 |
CN1826513A (en) | 2006-08-30 |
JP2006528346A (en) | 2006-12-14 |
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