CA2244166A1 - Inductive tuners for microwave driven discharge lamps - Google Patents
Inductive tuners for microwave driven discharge lamps Download PDFInfo
- Publication number
- CA2244166A1 CA2244166A1 CA002244166A CA2244166A CA2244166A1 CA 2244166 A1 CA2244166 A1 CA 2244166A1 CA 002244166 A CA002244166 A CA 002244166A CA 2244166 A CA2244166 A CA 2244166A CA 2244166 A1 CA2244166 A1 CA 2244166A1
- Authority
- CA
- Canada
- Prior art keywords
- waveguide
- lamp
- power
- disposed
- cavity
- 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.)
- Abandoned
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J65/00—Lamps without any electrode inside the vessel; Lamps with at least one main electrode outside the vessel
- H01J65/04—Lamps in which a gas filling is excited to luminesce by an external electromagnetic field or by external corpuscular radiation, e.g. for indicating plasma display panels
- H01J65/042—Lamps in which a gas filling is excited to luminesce by an external electromagnetic field or by external corpuscular radiation, e.g. for indicating plasma display panels by an external electromagnetic field
- H01J65/044—Lamps in which a gas filling is excited to luminesce by an external electromagnetic field or by external corpuscular radiation, e.g. for indicating plasma display panels by an external electromagnetic field the field being produced by a separate microwave unit
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J61/00—Gas-discharge or vapour-discharge lamps
- H01J61/02—Details
- H01J61/56—One or more circuit elements structurally associated with the lamp
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- Discharge Lamps And Accessories Thereof (AREA)
- Constitution Of High-Frequency Heating (AREA)
- Circuit Arrangements For Discharge Lamps (AREA)
Abstract
An RF powered electrodeless lamp (9) utilizing an inductive tuner (14) in the waveguide (6) which couples the RF power (2) to the lamp cavity (10, 12), for reducing reflected RF power and causing the lamp (9) to operate efficiently.
Description
W O 97/27611 PCTrUS97/01106 I~W ~llV~ ERS FOR MICRoWAVE DRrVEN DISCHARGE
I~AMPS
BACK~OUND OF THE lNV~ ON
a. Field of the Invention This invention refers to the field of radio-frequency driven arc lamps in which the structure includes a closed waveguide, and particularly to those lamps which utilize a magnetron as the source of power.
b. Description of the Prior Art These lamps employ an ionizable medium enclosed in a sealed transparent envelope which produces visible light or ultraviolet light when excited by an intense microwave field. The lamp envelope or bulb is enclosed in a metal container or cavity which confines the microwaves while providing for the escape of the light, usually by means of a metal screen. Microwaves are admitted into the cavity through an aperture which connects to the adjoining waveguide, the other end of which couples to the magnetron.
Rf power from the magnetron travels through the waveguide to the cavity and excites the discharge lamp. Any power that is not absorbed by the lamp reflects back to the magnetron. The aperture defining the end of the cavity may be used to define a resonance in the cavity which intensifies the fields at the bulb to provide increased power absorption, thus reducing the reflected power.
W O 97/27611 PCT~US97/01106 A magnetron is a self-excited oscillator with a direct connection between its resonator and the output load. Any reflection from the load has a strong effect on the performance, changing the operating frequency, the power output and the operating stability. strong reflections at a particular phase known as the "sink" reduce the stored energy in the magnetron's resonator, causing instability and fre~uency jumping.
The lamp itself places several different requirements on its power source. Before ionization, gases in the bulb do not absorb microwave power. The electric field intensity within the bulb must be built up to a high level to achieve breakdown. Once ionization occurs, the bulb must heat to evaporate any condensed fill materials. The impedance of the bulb is much lower than the non-ionized case, and changes as the bulb heats, bringing the condensates into the discharge. And finally the long term operating condition is reached in which light output efficiency is the dominant concern.
These impedance changes result in a variety of reflected values at the magnetron. The designer can adjust the aperture of the cavity, the length of the waveguide and may add a variety of tuning elements into the waveguide. The goal is to keep the high reflection before ionization away from the sink, to avoid frequency-jumping during the warm-up cycle and to provide a good match with stable characteristics during long-term operation.
W O 971276]Ll PCT~US97/01106 Other considerations may also enter into the design. The product needs to be economical, compact in size, durable, and reproducible. Cost prevents the use of isolators. Compact size holds the waveguide to a minimum length.
While many types of irises and posts are well-known in microwave design, the tuning element frequently used in microwave arc lamps is the capacitive screw or a fixed height knob of the same siz 2. This has the adLvantage of attaching to only one wall and is more easily installed than a post which must contact two opposite walls. When a waveguide length (between the magnetron antenna and the coupling slot) greater than half a guide-wavelength is available, this capacitive tuner may be used to match a moderate mismatch or any phase. The tuner has two effects. The reflection coefficient is added to the reflection coefficient of the load beyond it. Secondly, the effective length of the waveguide is increased by a small amount.
8UMMA~Y OF THE lNv~.~lON
In the course of making a new lamp design, the cavity and the coupling iris were established. The waveguide length and magnetron position were also established. However, the impedance match was not optimum and the waveguide length (referred to in the preceding paragraph) was less than half a wavelength. Attempts to add a W O 97/27611 PCTrUS97101106 capacitive tuner showed that it was unsuitable, the best location being directly above the magnetron antenna.
An inductive tuner was placed on the side wall of the waveguide between the magnetron and the cavity aperture. A metal protrusion at the side of a waveguide acts like an inductive iris, raising the cutoff frequency of the waveguide at its location.
Thus, the tuner provides a reflection coefficient with an inductive phase and shortens the effective length of the waveguide a small amount. The lamp design operates efficiently with this tuner. The inductive tuner may be a single block, semi-cylinder, or hemisphere or combination thereof attached to one side wall, or two such objects may face each other on opposite walls. These shapes are appropriate where the tuners are to be installed in a waveguide lS after it is built, as for example, by screws, soldering or welding.
The tuner may also be molded into the waveguide wall.
Depending upon the method of construction it may be advantageous to form the tuner to join to the upper and/or lower broad wall of the waveguide as a thick iris.
Figure 1 is a schematic representation of a microwave lamp.
Figure 2 illustrates an inductive tuner in the form of a single block.
CA 02244l66 l998-07-24 W O 97t27611 PCT~US97/01106 Figure 3 illustrates an inductive tuner in the form of two blocks which face each other on opposite waveguide walls.
Figure 4 illustrates an inductive tuner in the form of a semi-cy}inder contacting the broad walls of a waveguide.
Figure 5 illustrates an inductive tuner in the form of a semi-cylinder which does not contact the broad walls of a waveguide.
Re~erring to Figure 1, a microwave lamp is shown. Magnetron 2 has antenna 4 which protrudes into closed waveguide 6. At the other end of the waveguide, coupling slot 8 is located, which couples microwave power into the resonant cavity defined by bottom 10 and screen 12 in which bulb 9 is located. In accordance with the invention, inductive tuner 14 is attached to a side wall of the waveguide .
It is noted that the waveguide has broad walls and narrow walls (side walls). Since the magnetic field is high at the side walls, a metal protrusion placed there will act as an inductive tuner.
In any given lamp, the location of the tuner as well as its size and shape are determined by experimentation, with the aid of a network analyzer. As known to those skilled in the art, the network analyzer is first calibrated with the aid of a sliding short. The impedance i5 then observed with the lamp in the CA 02244l66 l998-07-24 W O 97/27611 PCTrUS97/01106 starting and running conditions without a tuner. If significant reflection is present when the lamp is at operating temperature a tuner of trial size and shape is used and its position changed to determine the position of optimum operation. If significant reflection is still present, the size and/or shape of the tuner is varied, and various positions again tried.
In the embodiment of Figure 1, rectangular waveguide 6 is 1.7'l high, 2.84" wide, and 4.8" long on the inside. The distance from the middle of the tuner to the slot end of the waveguide is about 1 ~/8", and the tuner is about 5/8" wide, 1 1/4" long, and has a thickness of about .35". The coupling slot 8 is 2 3/8" long and .53" wide. The microwave cavity is 2.g3" in diameter and 6.2"
tall. The bulb 9 is 35 mm inside diameter and contains a fill of sulfur and rare gas such as argon.
Both the waveguide and the tuner may be made of aluminum. It is preferable to ma~e the waveguide and the tuner of the same material to minimize corrosion.
A motor rotates both the shaft 20 to which bulb 9 is attached and blower wheel 22 which provides air for cooling the magnetron.
Figure 2 is a cut-away detail of waveguide 6 of Figure 1, and shows the inductive tuner in the form of metal block 14.
W O 97/27611 PCT~US97/01106 Figure 3 shows an alternative embodiment wherein two such blocks 14'a and 14 'k face each other on opposite waveguide walls.
Figure 4 shows a further alternative embodiment which utilizes a protrusion in the form of semicylinder 14'1 which contacts the top S and bottom broa~ walls 30 and 32 of the waveguide.
Figure 5 shows still a further embodiment which utilizes semi-cylinder 14''' which does not contact the broad walls of the waveguide.
While the invention has been disclosed employing illustrative embodiments, it is to be understood that variations will occur to those skilled in the art. For example the tuners may have different shapes than illustrated, or cylindrical posts may be used. The scope of the invention is defined by the following claims.
.
I~AMPS
BACK~OUND OF THE lNV~ ON
a. Field of the Invention This invention refers to the field of radio-frequency driven arc lamps in which the structure includes a closed waveguide, and particularly to those lamps which utilize a magnetron as the source of power.
b. Description of the Prior Art These lamps employ an ionizable medium enclosed in a sealed transparent envelope which produces visible light or ultraviolet light when excited by an intense microwave field. The lamp envelope or bulb is enclosed in a metal container or cavity which confines the microwaves while providing for the escape of the light, usually by means of a metal screen. Microwaves are admitted into the cavity through an aperture which connects to the adjoining waveguide, the other end of which couples to the magnetron.
Rf power from the magnetron travels through the waveguide to the cavity and excites the discharge lamp. Any power that is not absorbed by the lamp reflects back to the magnetron. The aperture defining the end of the cavity may be used to define a resonance in the cavity which intensifies the fields at the bulb to provide increased power absorption, thus reducing the reflected power.
W O 97/27611 PCT~US97/01106 A magnetron is a self-excited oscillator with a direct connection between its resonator and the output load. Any reflection from the load has a strong effect on the performance, changing the operating frequency, the power output and the operating stability. strong reflections at a particular phase known as the "sink" reduce the stored energy in the magnetron's resonator, causing instability and fre~uency jumping.
The lamp itself places several different requirements on its power source. Before ionization, gases in the bulb do not absorb microwave power. The electric field intensity within the bulb must be built up to a high level to achieve breakdown. Once ionization occurs, the bulb must heat to evaporate any condensed fill materials. The impedance of the bulb is much lower than the non-ionized case, and changes as the bulb heats, bringing the condensates into the discharge. And finally the long term operating condition is reached in which light output efficiency is the dominant concern.
These impedance changes result in a variety of reflected values at the magnetron. The designer can adjust the aperture of the cavity, the length of the waveguide and may add a variety of tuning elements into the waveguide. The goal is to keep the high reflection before ionization away from the sink, to avoid frequency-jumping during the warm-up cycle and to provide a good match with stable characteristics during long-term operation.
W O 971276]Ll PCT~US97/01106 Other considerations may also enter into the design. The product needs to be economical, compact in size, durable, and reproducible. Cost prevents the use of isolators. Compact size holds the waveguide to a minimum length.
While many types of irises and posts are well-known in microwave design, the tuning element frequently used in microwave arc lamps is the capacitive screw or a fixed height knob of the same siz 2. This has the adLvantage of attaching to only one wall and is more easily installed than a post which must contact two opposite walls. When a waveguide length (between the magnetron antenna and the coupling slot) greater than half a guide-wavelength is available, this capacitive tuner may be used to match a moderate mismatch or any phase. The tuner has two effects. The reflection coefficient is added to the reflection coefficient of the load beyond it. Secondly, the effective length of the waveguide is increased by a small amount.
8UMMA~Y OF THE lNv~.~lON
In the course of making a new lamp design, the cavity and the coupling iris were established. The waveguide length and magnetron position were also established. However, the impedance match was not optimum and the waveguide length (referred to in the preceding paragraph) was less than half a wavelength. Attempts to add a W O 97/27611 PCTrUS97101106 capacitive tuner showed that it was unsuitable, the best location being directly above the magnetron antenna.
An inductive tuner was placed on the side wall of the waveguide between the magnetron and the cavity aperture. A metal protrusion at the side of a waveguide acts like an inductive iris, raising the cutoff frequency of the waveguide at its location.
Thus, the tuner provides a reflection coefficient with an inductive phase and shortens the effective length of the waveguide a small amount. The lamp design operates efficiently with this tuner. The inductive tuner may be a single block, semi-cylinder, or hemisphere or combination thereof attached to one side wall, or two such objects may face each other on opposite walls. These shapes are appropriate where the tuners are to be installed in a waveguide lS after it is built, as for example, by screws, soldering or welding.
The tuner may also be molded into the waveguide wall.
Depending upon the method of construction it may be advantageous to form the tuner to join to the upper and/or lower broad wall of the waveguide as a thick iris.
Figure 1 is a schematic representation of a microwave lamp.
Figure 2 illustrates an inductive tuner in the form of a single block.
CA 02244l66 l998-07-24 W O 97t27611 PCT~US97/01106 Figure 3 illustrates an inductive tuner in the form of two blocks which face each other on opposite waveguide walls.
Figure 4 illustrates an inductive tuner in the form of a semi-cy}inder contacting the broad walls of a waveguide.
Figure 5 illustrates an inductive tuner in the form of a semi-cylinder which does not contact the broad walls of a waveguide.
Re~erring to Figure 1, a microwave lamp is shown. Magnetron 2 has antenna 4 which protrudes into closed waveguide 6. At the other end of the waveguide, coupling slot 8 is located, which couples microwave power into the resonant cavity defined by bottom 10 and screen 12 in which bulb 9 is located. In accordance with the invention, inductive tuner 14 is attached to a side wall of the waveguide .
It is noted that the waveguide has broad walls and narrow walls (side walls). Since the magnetic field is high at the side walls, a metal protrusion placed there will act as an inductive tuner.
In any given lamp, the location of the tuner as well as its size and shape are determined by experimentation, with the aid of a network analyzer. As known to those skilled in the art, the network analyzer is first calibrated with the aid of a sliding short. The impedance i5 then observed with the lamp in the CA 02244l66 l998-07-24 W O 97/27611 PCTrUS97/01106 starting and running conditions without a tuner. If significant reflection is present when the lamp is at operating temperature a tuner of trial size and shape is used and its position changed to determine the position of optimum operation. If significant reflection is still present, the size and/or shape of the tuner is varied, and various positions again tried.
In the embodiment of Figure 1, rectangular waveguide 6 is 1.7'l high, 2.84" wide, and 4.8" long on the inside. The distance from the middle of the tuner to the slot end of the waveguide is about 1 ~/8", and the tuner is about 5/8" wide, 1 1/4" long, and has a thickness of about .35". The coupling slot 8 is 2 3/8" long and .53" wide. The microwave cavity is 2.g3" in diameter and 6.2"
tall. The bulb 9 is 35 mm inside diameter and contains a fill of sulfur and rare gas such as argon.
Both the waveguide and the tuner may be made of aluminum. It is preferable to ma~e the waveguide and the tuner of the same material to minimize corrosion.
A motor rotates both the shaft 20 to which bulb 9 is attached and blower wheel 22 which provides air for cooling the magnetron.
Figure 2 is a cut-away detail of waveguide 6 of Figure 1, and shows the inductive tuner in the form of metal block 14.
W O 97/27611 PCT~US97/01106 Figure 3 shows an alternative embodiment wherein two such blocks 14'a and 14 'k face each other on opposite waveguide walls.
Figure 4 shows a further alternative embodiment which utilizes a protrusion in the form of semicylinder 14'1 which contacts the top S and bottom broa~ walls 30 and 32 of the waveguide.
Figure 5 shows still a further embodiment which utilizes semi-cylinder 14''' which does not contact the broad walls of the waveguide.
While the invention has been disclosed employing illustrative embodiments, it is to be understood that variations will occur to those skilled in the art. For example the tuners may have different shapes than illustrated, or cylindrical posts may be used. The scope of the invention is defined by the following claims.
.
Claims (12)
1) An RF powered electrodeless lamp comprising, means for generating RF power, a bulb containing a discharge forming medium disposed in a cavity, a waveguide for coupling said RF power to said cavity, said waveguide having a coupling slot, and an inductive tuner disposed in said waveguide.
2) The lamp of claim 1 wherein said inductive tuner comprises at least one metal protrusion disposed on a waveguide wall.
3) The lamp of claim 2 wherein said waveguide has narrow walls and broad walls, wherein said metal protrusion is disposed on a narrow wall.
4) The lamp of claim 3 wherein said at least one metal protrusion comprises a metal block.
5) The lamp of claim 4 wherein said metal block is rectangular.
6) The lamp of claim 5 wherein said at least one metal block comprises two rectangular metal blocks disposed on opposite waveguide walls.
7) The lamp of claim 4 wherein said at least one metal block comprises a semi-cylindrical metal block.
8) The lamp of claim 7 wherein said metal block contacts said broad walls at its extreme ends.
9) The lamp of claim 7 wherein said metal block at its extreme ends does not contact said broad walls.
10) The lamp of claim 2 wherein said means for generating RF power is a magnetron having an antenna and wherein the waveguide length from the antenna to said coupling slot is less than half a wavelength.
11) An RF powered electrodeless lamp comprising means for generating RF power, a bulb containing a discharge forming medium disposed in a cavity, a waveguide for coupling said RF power to said cavity, and inductive tuning means disposed in said waveguide for minimizing power which is reflected back to said means for generating RF power.
12) The lamp of claim 11 wherein said waveguide has a coupling slot.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US1067196P | 1996-01-26 | 1996-01-26 | |
US60/010,671 | 1996-01-26 |
Publications (1)
Publication Number | Publication Date |
---|---|
CA2244166A1 true CA2244166A1 (en) | 1997-07-31 |
Family
ID=21746850
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA002244166A Abandoned CA2244166A1 (en) | 1996-01-26 | 1997-01-24 | Inductive tuners for microwave driven discharge lamps |
Country Status (12)
Country | Link |
---|---|
US (1) | US5977712A (en) |
EP (1) | EP1016124A4 (en) |
JP (1) | JP2000504144A (en) |
KR (1) | KR19990081919A (en) |
CN (1) | CN1055783C (en) |
AU (1) | AU1837297A (en) |
CA (1) | CA2244166A1 (en) |
HU (1) | HUP9901854A3 (en) |
IL (1) | IL125295A0 (en) |
TW (1) | TW388909B (en) |
WO (1) | WO1997027611A1 (en) |
ZA (1) | ZA97606B (en) |
Families Citing this family (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3174296B2 (en) * | 1998-07-15 | 2001-06-11 | 松下電子工業株式会社 | Microwave electrodeless discharge lamp device |
JP3580205B2 (en) * | 2000-01-18 | 2004-10-20 | ウシオ電機株式会社 | Electromagnetic energy excitation point light source lamp device |
EP1279187B1 (en) * | 2000-04-26 | 2004-07-14 | Cornell Research Foundation, Inc. | Lamp utilizing fiber for enhanced starting field |
US6922021B2 (en) * | 2000-07-31 | 2005-07-26 | Luxim Corporation | Microwave energized plasma lamp with solid dielectric waveguide |
KR100442374B1 (en) * | 2001-07-20 | 2004-07-30 | 엘지전자 주식회사 | Microwave lighting system |
KR20030026806A (en) * | 2001-09-28 | 2003-04-03 | 주식회사 엘지이아이 | Apparatus and method for intercepting leakage of microwave |
US6577074B1 (en) * | 2001-12-28 | 2003-06-10 | Fusion Uv Systems, Inc. | Lighting system |
KR100464057B1 (en) * | 2003-03-11 | 2005-01-03 | 엘지전자 주식회사 | Plasma lighting system |
WO2005015607A1 (en) * | 2003-08-08 | 2005-02-17 | Expantech Co., Ltd. | Plasma lamp and manufacturing method thereof |
KR100608882B1 (en) * | 2004-06-30 | 2006-08-08 | 엘지전자 주식회사 | Waveguide system of electrodeless lighting device |
KR100668259B1 (en) * | 2004-11-09 | 2007-01-12 | 전제일 | Electrodeless Cascade Multiple Fluorescent Lighting Device Using Microwave |
KR101943321B1 (en) * | 2012-11-12 | 2019-01-29 | 엘지전자 주식회사 | Lighting apparatus |
CN103165401B (en) * | 2013-02-06 | 2015-11-04 | 湖北源光电器科技有限公司 | A kind of electrodeless Metal halogen lamp of microwave plasma of miniaturization |
CN109553155A (en) * | 2018-12-07 | 2019-04-02 | 四川麦克优威环保科技有限责任公司 | Electrodeless ultraviolet sterilization device for sewage treatment plant |
Family Cites Families (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3911318A (en) * | 1972-03-29 | 1975-10-07 | Fusion Systems Corp | Method and apparatus for generating electromagnetic radiation |
US3993927A (en) * | 1975-04-21 | 1976-11-23 | Gte Laboratories Incorporated | Electrodeless light source |
US4002944A (en) * | 1975-04-21 | 1977-01-11 | Gte Laboratories Incorporated | Internal match starter for termination fixture lamps |
US4042850A (en) * | 1976-03-17 | 1977-08-16 | Fusion Systems Corporation | Microwave generated radiation apparatus |
US4083016A (en) * | 1976-12-27 | 1978-04-04 | Varian Associates, Inc. | Coupled-cavity microwave oscillator |
JPH0610972B2 (en) * | 1985-09-09 | 1994-02-09 | 新日本無線株式会社 | Microwave discharge device |
US4737738A (en) * | 1987-05-11 | 1988-04-12 | Agence Spatiale Europeenne | Extended interaction device tuned by movable delay line structure |
US4975625A (en) * | 1988-06-24 | 1990-12-04 | Fusion Systems Corporation | Electrodeless lamp which couples to small bulb |
US4990829A (en) * | 1989-04-21 | 1991-02-05 | Potomac Photonics, Inc. | High frequency discharge apparatus with hollow waveguide input section |
US5404076A (en) * | 1990-10-25 | 1995-04-04 | Fusion Systems Corporation | Lamp including sulfur |
US5448135A (en) * | 1993-10-28 | 1995-09-05 | Fusion Lighting, Inc. | Apparatus for coupling electromagnetic radiation from a waveguide to an electrodeless lamp |
US5525865A (en) * | 1994-02-25 | 1996-06-11 | Fusion Lighting, Inc. | Compact microwave source for exciting electrodeless lamps |
-
1997
- 1997-01-23 US US08/787,175 patent/US5977712A/en not_active Expired - Lifetime
- 1997-01-24 EP EP97903942A patent/EP1016124A4/en not_active Withdrawn
- 1997-01-24 KR KR1019980705632A patent/KR19990081919A/en not_active Application Discontinuation
- 1997-01-24 ZA ZA9700606A patent/ZA97606B/en unknown
- 1997-01-24 IL IL12529597A patent/IL125295A0/en unknown
- 1997-01-24 AU AU18372/97A patent/AU1837297A/en not_active Abandoned
- 1997-01-24 CN CN97191848A patent/CN1055783C/en not_active Expired - Fee Related
- 1997-01-24 HU HU9901854A patent/HUP9901854A3/en unknown
- 1997-01-24 CA CA002244166A patent/CA2244166A1/en not_active Abandoned
- 1997-01-24 WO PCT/US1997/001106 patent/WO1997027611A1/en not_active Application Discontinuation
- 1997-01-24 TW TW086100787A patent/TW388909B/en not_active IP Right Cessation
- 1997-01-24 JP JP9527008A patent/JP2000504144A/en active Pending
Also Published As
Publication number | Publication date |
---|---|
CN1055783C (en) | 2000-08-23 |
HUP9901854A3 (en) | 2002-04-29 |
WO1997027611A1 (en) | 1997-07-31 |
HUP9901854A2 (en) | 1999-09-28 |
EP1016124A1 (en) | 2000-07-05 |
AU1837297A (en) | 1997-08-20 |
CN1209904A (en) | 1999-03-03 |
JP2000504144A (en) | 2000-04-04 |
EP1016124A4 (en) | 2000-07-05 |
KR19990081919A (en) | 1999-11-15 |
ZA97606B (en) | 1997-09-16 |
IL125295A0 (en) | 1999-03-12 |
US5977712A (en) | 1999-11-02 |
TW388909B (en) | 2000-05-01 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
EEER | Examination request | ||
FZDE | Discontinued |