WO2008129481A2 - Lampe à décharge gazeuse basse pression - Google Patents

Lampe à décharge gazeuse basse pression Download PDF

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Publication number
WO2008129481A2
WO2008129481A2 PCT/IB2008/051485 IB2008051485W WO2008129481A2 WO 2008129481 A2 WO2008129481 A2 WO 2008129481A2 IB 2008051485 W IB2008051485 W IB 2008051485W WO 2008129481 A2 WO2008129481 A2 WO 2008129481A2
Authority
WO
WIPO (PCT)
Prior art keywords
electrode
discharge lamp
electrical energy
filling
conducting surface
Prior art date
Application number
PCT/IB2008/051485
Other languages
English (en)
Other versions
WO2008129481A3 (fr
Inventor
Renatus W. C. Van Der Veeken
Original Assignee
Koninklijke Philips Electronics N.V.
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 Koninklijke Philips Electronics N.V. filed Critical Koninklijke Philips Electronics N.V.
Publication of WO2008129481A2 publication Critical patent/WO2008129481A2/fr
Publication of WO2008129481A3 publication Critical patent/WO2008129481A3/fr

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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
    • H01J65/046—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 using capacitive means around the vessel
    • 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
    • H05B41/2806—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 and specially adapted for lamps without electrodes in the vessel, e.g. surface discharge lamps, electrodeless discharge lamps
    • 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 invention relates to a low-pressure gas discharge lamp.
  • UV ultra-violet
  • IR infra-red
  • Hot cathode fluorescent lamps are well known for use in backlight display devices, such as liquid crystal displays (LCD), and for other general applications.
  • a high frequency voltage with a frequency ranging from between 20 kHz to 100 kHz for instance is supplied to a discharge space within a discharge vessel or tube of the
  • HCFL forming a discharge resulting in the generation of electromagnetic radiation as a result of which a display device can be illuminated.
  • a HCFL requires that its hot cathode is kept at an increased temperature permanently, even when the HFCL is temporarily turned off, in order to secure instantaneous correct functioning of the lamp after switching it on again.
  • the need to continuously power the HCFL is unfavorable from an energy preservation point of view.
  • cold cathode fluorescent lamps (CCFL) or alternatively external electrode fluorescent lamps (EEFL). do not require continuous powering during a temporary standby state of the lamp, as a result of which an LCD can be illuminated relatively economically.
  • An EEFL usually comprises a discharge vessel of a suitable glass material, which vessel is provided at its ends with conductive coatings.
  • the conductive coatings function as capacitive electrodes, between which a discharge extends, during lamp operation, along the axial distance between both ends.
  • the EEFL achieves an energy saving relative to the HCFL by applying duty-cycle dimming to its alternating supply, and thus no extra heating is required compared to HCFL.
  • the object is achieved by providing a light-transmitting discharge vessel comprising a filling, the filling being configured to emit a discharge of light when excited; a supply of electrical energy; a first and a second electrode, disposed outside the discharge vessel, the electrodes being configured for supplying the electrical energy to the filling to excite the filling between the electrodes, the first electrode comprising a plurality of electrical supply channels; and a current controller, configured to control the portion of the electrical energy supplied by each channel to the filling.
  • the low-pressure discharge lamp may be configured to supply the electrical energy to the filling by capacitive coupling.
  • each electrical supply channel comprises a conducting surface enclosing a section of the discharge vessel, the conducting surface being disposed such that the electrical energy is transferable by capacitive coupling to the filling.
  • a capacitively coupled electrode in which the length of the edges of the conducting surface are increased by: the edges of the conducting surface comprising undulations or serrations, and/or the conducting surface comprising perforations.
  • the sheath resistance Rsh of each channel is distributed along the edge of the external conducting surface. Therefore Rsh may be reduced by increasing the length of this edge.
  • the length of the edge may be increased by adding undulations or serrations. Perforation of the conducting surface will also increase the effective edge length.
  • the section of the discharge vessel is cylindrical; the conducting surface covers a perimeter of the section; and the conducting surface has a trapezoidal cross- section.
  • the ring may be made with a trapezoidal cross-section, which increases the edge length compared to a ring with a rectangular cross-section.
  • "cylindrical” in this context means any 3- dimensional shape suitable as a discharge vessel. In particular, the term embraces shapes that do not have a circular transverse cross-section.
  • the current controller comprises a plurality of impedances connected electrically in the plurality of electrical supply channels such that each channel has its current controlled by at least one impedance.
  • Impedances per channel provide a direct method of controlling the current per channel, and allow a degree of independence in setting the current.
  • the plurality of impedances are connected electrically in the plurality of electrical supply channels such that a first and a second channel have their current controlled by a common impedance. In some applications, it may be advantageous to allow an increase of the degree of dependence between channel currents. Such a configuration also allows use to be made of impedances integrated into the electrode.
  • each impedance is a capacitor; each capacitor comprises a first and a second conducting surface separated by an insulating surface; each first conducting surface is disposed adjacent to the discharge vessel to transfer the electrical energy of the channel to the filling; and each second conducting surface is connected electrically to the electrical energy supply.
  • the use of capacitors as impedances is advantageous because they are relatively simple to construct, using two conducting surfaces sandwiching an insulator, and the dimensions and properties may be varied to achieve the desired impedance.
  • the second electrode comprises a further plurality of electrical supply channels; and the current controller is further configured to control the portion of the electrical energy supplied by each of the second plurality of channels to the filling. This allows the end losses at more than one location to be improved by the invention.
  • Figure 1 shows a cross-sectional view through the longitudinal axis of a discharge lamp according to the invention
  • Figure 2A shows a longitudinal cross-sectional view and Figure 2B shows a transverse cross-sectional view of a discharge lamp according to the invention
  • Figure 3A shows a longitudinal cross-sectional view and Figure 3B shows a transverse cross-sectional view of a discharge lamp according to the invention
  • Figure 4 shows a longitudinal cross-sectional view of a discharge lamp according to the invention
  • Figure 5 shows a schematic electrical circuit diagram of the electrical connections to a discharge lamp according to the invention
  • Figure 6 shows a schematic electrical circuit diagram of the electrical connections to a discharge lamp according to the invention
  • Figure 7 shows a schematic electrical circuit diagram of the electrical connections to a discharge lamp according to the invention
  • Figure 8 shows cross-sectional views of discharge lamp electrode rings according to the invention
  • FIGS 9A, 9B and 9C depict cross-sectional views of discharge lamp electrode rings according to the invention.
  • FIGS 1OA, 1OB and 1OC depict cross-sectional views of discharge lamp electrode rings according to the invention
  • FIG. 11 depicts cross-sectional views of discharge lamp electrode rings according to the invention.
  • Figure 12 depicts cross-sectional views of discharge lamp electrode rings according to the invention.
  • FIG. 1 shows very schematically a cross-sectional view of an embodiment of a discharge lamp 10.
  • the gas discharge lamp 10 comprises a light transmitting discharge vessel 20 which encloses a discharge space 50 in a gas-tight manner.
  • the discharge vessel 20 comprises a gas filling 60.
  • the gas discharge lamp 10 further comprises a first electrode 30 and a second electrode 40, connected via electrical connections 5 to a supply of alternating electrical energy 80.
  • the electrodes 30, 40 capacitively couple energy into the filling 60 to excite it, and to cause and maintain a discharge in the filling 60 between the two electrodes 30, 40.
  • the electrodes 30, 40 are conducting surfaces usually attached to the outer wall of the discharge vessel 20.
  • the discharge vessel 20 is cylindrical, and the capacitive electrodes 30, 40 are conducting plates attached to the end of the discharge vessel 20.
  • a discharge is initiated. This discharge is generally located between the two electrodes 30, 40 and is indicated in Figure 1 as the discharge space 50.
  • Figure 3 A very schematically shows a longitudinal cross-sectional view of an embodiment of a discharge lamp 14.
  • Figure 3B shows a transverse cross-sectional view through the electrode 34 and the discharge vessel 24.
  • the gas discharge lamp 14 according to the invention comprises a light transmitting discharge vessel 24 which encloses a discharge space 54 in a gas-tight manner.
  • the discharge vessel 24 comprises a gas filling 60.
  • the gas discharge lamp 14 further comprises a first electrode 34 and a second electrode of similar type (not shown), disposed in suitable recesses in the wall of the discharge vessel 24, and connected via electrical connections 5 to a supply of alternating electrical energy (not shown).
  • the electrode 34 is a conductive ring which covers a section of the discharge tube 24. To ensure efficient capacitive coupling of electrical energy into the filling 60, the outer conducting surface of the ring electrode 34 contacts and closely follows the outer wall of the discharge vessel 24 within the recess.
  • the gas discharge lamp 10,17 according to the invention is configured for low-pressure discharge, a molecular gas discharge takes place which emits radiation comprising the characteristic lines of the filling.
  • light generation in a low-pressure gas discharge lamp is based on the principle that charge carriers, particularly electrons but also ions, are accelerated by an electric field applied between the electrodes 30,40 in the discharge vessel 20. Collisions of these accelerated electrons and ions with the gas atoms or molecules in the gas filling in the discharge vessel cause these gas atoms or molecules to be dissociated, excited or ionized. When the atoms or molecules of the gas filling return to the ground state, a more or less substantial part of the excitation energy is converted to radiation.
  • the emission spectrum of the low-pressure gas discharge lamp 10, 17 is determined by the gas filling 60, together with, for example, the pressure and temperature inside the discharge vessel 20,27.
  • the filling typically comprises an inert gas, for example, helium, neon, argon, krypton and/or xenon, and different metal compounds such as metal atoms and molecules which all contribute to the emission spectrum of the low-pressure gas discharge lamp 10, 17 according to the invention.
  • FIG. 2A very schematically shows a longitudinal cross-sectional view of an embodiment of a discharge lamp 12.
  • Figure 2B shows a transverse cross-sectional view through the electrode 32 and the discharge vessel 20.
  • the gas discharge lamp 12 comprises a light transmitting discharge vessel 20 which encloses a discharge space 52 in a gas-tight manner.
  • the discharge vessel 20 is substantially circular in transverse cross-section, and comprises a gas filling 60.
  • the gas discharge lamp 12 further comprises a first electrode 32 and a second electrode of similar type (not shown), connected via electrical connections 5 to a supply of alternating electrical energy (not shown).
  • the electrode 32 is a conductive ring, also substantially circular in cross-section, which covers a section of the outer wall of the discharge vessel 20. To ensure efficient capacitive coupling of electrical energy into the filling 60, the inner conducting surface of the ring contacts and closely follows the outer wall of the discharge vessel 20.
  • FIG 4 very schematically shows a longitudinal cross-sectional view of a discharge lamp 13 according to the invention.
  • the gas discharge lamp 13 comprises a light transmitting discharge vessel 20 which encloses a discharge space 56 in a gas-tight manner.
  • the discharge vessel 20 is substantially circular in transverse cross-section.
  • the gas discharge lamp 13 further comprises a first electrode 32 and a second electrode 42, connected via electrical connections 5 to a supply of alternating electrical energy 80.
  • the second electrode 42 is of the type depicted in Figures 2A and 2B.
  • the first electrode 32 comprises four conductive rings 32a,32b,32c,32d which are also substantially circular in cross-section, covering a section of the outer wall of the discharge vessel 20.
  • Each electrode ring 32a,2b,32c,32d is connected via an electrical connection 5a,5b,5c,5d and via an impedance 70a,70b,70c,70d to the electrical energy supply 80, to form four parallel channels for the current supplied to the filling 60.
  • the current through each channel may be adjusted by varying the impedance 70a,70b,70c,70d electrically connected in that channel - however, it will be apparent to the skilled person that the parallel nature of the connections means that varying one impedance 70a,70b,70c,70d may imply an adjustment of the current in more than one channel.
  • the impedances 70a,70b,70c,70d are comprised in the electrical connections 5a,5b,5c,5d of the electrode rings 32a,32b,32c,32d. However, it will be apparent to the skilled person that the impedances may also be comprised in the electrical energy power supply 80.
  • the impedances 70a,70b,70c,70d may be discrete components; they may be integrated into the electrical wiring and the connections 5a,5b,5c,5d or a combination thereof.
  • the total current of the electrical energy supplied I is divided into several smaller electrical currents.
  • the current supplied by each channel Ic flows through its own sheath, but the sheath resistance for each channel remains the same, namely R SH -
  • the total end losses for an electrode with four channels is therefore
  • the reduction achieved may be lower due to the more complex coupling of the electrical energy into the filling through the plurality of channels. Additionally it has been observed that Rsh increases with decreasing current I, although it is believed that at very low currents, Rsh may be independent of I - for the example given above, the improvement may then approach said factor of 4 at these low currents. It is also believed that the filling and the conditions inside the discharge vessel 20 may also influence Rsh. However, for general lighting purposes, even a reduction in power loss approaching 10% is considered substantial and advantageous.
  • the invention is based upon the insight that differences between the channels may result in an uneven current distribution over the plurality of electrode channels. These differences may be due to factors such as the construction of the electrodes; the electrical connections; the properties of the filling 60 inside the discharge vessel 20,27 during operation; and the position where the energy is coupled into the filling 60 by the electrode in relation to the discharge. The differences may result in a difference in impedance and/or sheath resistance Rsh, which causes the uneven current distribution. It is believed that these differences cause the arc of discharge inside the discharge vessel to only attach to a small part of the total electrode surface, resulting in an increase in end losses. By controlling the portion of the electrical energy supplied by each channel to the filling, imbalances in the arc attachment may be corrected, resulting in the attachment of the discharge arc to a larger part of the total electrode surface, and thus also to reduced power losses.
  • FIG. 5 shows a schematic electrical circuit diagram of the electrical connections in the channels depicted in Figure 4. Note that the electrical connections to the second electrode 42 are not shown.
  • Each electrode ring 32a,32b,32c,32d is connected to the electrical energy supply 80, and each connection comprises an impedance 70a,70b,70c,70d.
  • the distribution of the electrical supply current to the electrode 32 - that is the portion of the total current that flows through each channel - may be adjusted by varying the impedance 70a,70b,70c,70d, however, it will be apparent to the skilled person that the parallel nature of the connections means that varying one impedance 70a,70b,70c,70d may imply an adjustment of the current in more than one channel.
  • the impedances may be resistors, capacitors, inductors or any combination of these components.
  • these impedances should be lossless to reduce the power loss due to the impedances 70a,70b,70c,70d. It may be advantageous to make the current through a particular channel more directly dependent on the current flowing through another channel.
  • Figure 6 depicts a schematic electrical circuit diagram in which the impedances are configured to do this. The electrical connections to the second electrode 42 are not shown.
  • the impedances comprised in each channel may be summarized as: - the channel of electrode ring 32a comprises a single impedance 70a the channel of electrode ring 32b comprises a single impedance 70b the channel of electrode ring 32c comprises the impedances 70c and 70b the channel of electrode ring 32d comprises the impedances 7Od, 70c and 70b.
  • the channels of electrode rings 32c and 32d have two common impedances, namely 70b and 70c, and the channels of electrode rings 32b and 32c have a common impedance, namely 70b.
  • the invention provides a very flexible solution to provide the most optimum current distribution during lamp operation. It may also be advantageous to configure the current controller to vary the current distribution through the channels depending upon the mode of operation. For example, it may be desired to reduce the luminous output of the discharge lamp (dimming) by varying the duty cycle. The current controller may do this by switching between different impedance networks, or by employing appropriate common impedances or some combination of these. This provides considerable flexibility to control the end losses in different modes of operation.
  • Electrode ring 32e is an electrode ring of the type depicted in Figure 2A, but comprises an impedance connected between the electrode ring 32e and the electrical connection 5e.
  • the impedance is a capacitor comprised of an insulator 132 sandwiched between a conducting region of the electrode ring 32e and a conducting region of the electrical connection 5e.
  • the value of the capacitance is determined by the areas of the conducting regions, the permittivity of the insulating material 132 and the distance between the conducting regions.
  • the channel of electrode ring 32e thus comprises a capacitor in its electrical connection to the electrical discharge supply.
  • Electrode rings 32f,32g are of a similar type to electrode ring 32e.
  • a capacitor is formed between the channel of electrode ring 32f and the channel of ring 32g, by sandwiching an insulating ring 131 between conducting electrode ring 32f and conducting electrode ring 32g. In this way, the current portions through the channels of electrode rings 32f and 32g have a common impedance.
  • the degree to which the currents are dependent on each other is dependent upon the value of the capacitance, and the way in which the electrode rings 32f and 32g are connected by their electrical connections 5f, 5g to the electrical energy supply 80. It may be advantageous to connect only one of the electrode rings 32f, 32g to the electrical power supply, thus creating a total dependence of one channel current on another. This flexibility is available in any situation where an impedance is formed between two electrodes.
  • Electrode rings 32h,32i are of a similar type to electrode ring 32e.
  • a capacitor is formed between the channel of electrode ring 32h and the channel of ring 32i, by sandwiching an insulator 134 between a conducting area of the electrode ring 32h and a conducting area of electrode ring 32i.
  • the current portions through the channels of electrode rings 32h and 32i have a common impedance.
  • the first electrode 32 comprises three channels, each comprising an electrode ring 32a,32b,32c and an impedance 70a,70b,70c.
  • the second electrode 42 comprises three channels, each comprising an electrode ring 42a,42b,42c and an impedance 90a,90b,90c.
  • the configurations of the invention described in relation to the first electrode 32 may also be applied to the second electrode 42.
  • the reduction in end losses achieved by the invention may be applied to both ends.
  • the schematic representation of Figure 7 depicts an identical layout of impedances and connections, in practice the impedances and connections may need to be implemented differently to achieve a substantially identical current distribution.
  • the inner wall of the discharge vessel 20, 27 may be provided with different phosphors, such as red and blue, at different positions.
  • the degree of asymmetry by controlling the current distributions, the color of the lamp may be changed.
  • FIGS 9A and 9B depict a further example of an electrode comprising a plurality of channels.
  • the electrode 36 comprises conductive electrode rings 36a,36b,36c and insulating rings 136b, 136c disposed between the electrode rings 36a, 36b and 36b,36c respectively.
  • Each electrode ring 36a, 36b,36c is provided with a direct electrical connection 5a, 5b, 5c, for connection to the electrical energy supply 80, although it is not required that all connections are used.
  • the current portion through the channels of electrode rings 36a and 36b has a common impedance formed by the insulating ring 136b
  • the current portion through the channels of electrode rings 36b and 36c has a common impedance formed by the insulating ring 136c.
  • Each electrode ring 36a,36b,36c is constructed to have two regions with different diameters and an intermediate region, such that the electrode regions may interlock and partially overlap.
  • FIGS 1OA and 1OB depict a further example of an electrode comprising a plurality of channels.
  • the electrode 38 comprises conductive electrode rings 38a,38b,38c and a contiguous insulating ring 138 covering the electrode rings 38a,38b,38c.
  • the electrode 38 further comprises an electrical connection 6 which comprises a conductive ring covering the insulating ring 138.
  • the electrical connection 6 is connected to the electrical energy supply 80.
  • capacitors are formed between the electrode rings 38a,38b,38c and the conducting ring of the electrical connection 6.
  • the value of the capacitors is influenced in particular by the area of the outer conducting surface of each electrode ring 38a,38b,38c.
  • capacitors may be modified to form other impedance types.
  • resistors will be formed.
  • more than one type of impedance may be formed at the same location.
  • a working system may comprise one or more combinations of the impedance types described. It will be apparent to the skilled person that the invention may also be employed to control the current distribution to any discharge lamp, and that it is not limited to lamps employing capacitive coupling to couple the electrical energy into the filling 60. It is therefore within the skill of those in the art to modify the described embodiment to employ a different coupling method. It will be apparent to the skilled person that the embodiments described using electrode rings may be modified to use electrodes such as those depicted in Figures IA and 3A.
  • a conducting surface must be present at the outer wall of the discharge vessel 20. Although described as such, it is not essential that the invention be implemented with channels providing a symmetrical conducting surface to the discharge vessel 20.
  • the ability to control the current supplied through each channel means that electrodes of any shape may be employed. This allows different light effects to be generated at the electrode regions.
  • the electrode conducting surfaces 35a,35b,35c,35d,35e depicted in Figure 12 may be useful.
  • Each surface is provided with an electrical connection to the discharge supply, either directly as depicted via the electrical connections 5a,5b,5c,5d,5e, or via an indirect capacitive connection as depicted in Figures 1OA and 1OB, or via some combination of connections.
  • FIG. 10 depicts modified electrode rings 233, 234, 235, 237 which are similar in type to the electrode rings 32a, 32b, 32c, 32d in Figure 5.
  • Electrode ring 233 has an edge comprising undulations, electrode ring 234 has an edge comprising serrations, and electrode ring 235 comprises perforations; all these measures increase the length of the edge presented to the outer wall of the discharge vessel, compared to the electrode rings of Figure 5.
  • the length of the edge may be increased by making external conducting surfaces that are not cylindrically symmetric, but slanted, as is depicted for electrode ring 237.
  • the inner conducting surface of the ring fully remains in contact with the outer wall of the discharge vessel.
  • the longitudinal axis of the ring 237 therefore lies at a non-perpendicular angle to the longitudinal axis of the discharge vessel 20, while the ring still makes contact over the whole perimeter with the outer wall of the discharge vessel 20.
  • the cross-section of the ring has a trapezoidal shape instead of a rectangular one.
  • Figure 9C depicts a slanted version 37a of the ring 36a depicted in Figure 9B.
  • Figure 1OC depicts a slanted version 39b, 39c of the rings 38b,38c depicted in Figure 1OB.
  • the longitudinal axis of the ring would lie at a non-perpendicular angle to the longitudinal axis of the discharge vessel 20 while the outer conducting surface of the ring would still make contact over the whole perimeter with the outer wall of the discharge vessel 20.
  • the cross-section of the ring would have a trapezoidal shape instead of a rectangular one.
  • a low-pressure discharge lamp is provided with an electrode comprising a plurality of said channels, and a current controller for controlling the current distribution through these channels.
  • Current control may be provided by using a suitable network of impedances in the electrical connections to the electrode. This permits a high degree of control over how the electrical energy is coupled into the gas filling, enabling the end losses to be reduced. Additionally, the current controller may also be used to create a wide range of light distributions emitted by the discharge lamp.

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Circuit Arrangements For Discharge Lamps (AREA)

Abstract

En résumé, l'invention concerne une lampe à décharge basse pression qui comporte une électrode comprenant plusieurs canaux et un régulateur de courant pour réguler la distribution de courant à travers ces canaux. La régulation de courant peut être assurée à l'aide d'un réseau approprié d'impédances dans les connexions électriques de l'électrode. Ceci permet un degré élevé de régulation de la manière dont l'énergie électrique est couplée dans le remplissage de gaz, permettant aux pertes d'extrémité d'être réduites. De plus, le régulateur de courant peut également être utilisé pour créer une large plage de distributions de lumière émise par la lampe à décharge.
PCT/IB2008/051485 2007-04-24 2008-04-17 Lampe à décharge gazeuse basse pression WO2008129481A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP07106820.9 2007-04-24
EP07106820 2007-04-24

Publications (2)

Publication Number Publication Date
WO2008129481A2 true WO2008129481A2 (fr) 2008-10-30
WO2008129481A3 WO2008129481A3 (fr) 2009-01-29

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102009059705A1 (de) * 2009-12-18 2011-06-22 Sick Maihak GmbH, 79183 Gasentladungslampe

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5146140A (en) * 1991-06-18 1992-09-08 Gte Products Corporation Method and apparatus to reduce Hg loss in rf capacitively coupled gas discharges
EP0593312A2 (fr) * 1992-10-16 1994-04-20 Flowil International Lighting (Holding) B.V. Source de lumière fluorescente
EP0766286A1 (fr) * 1991-05-31 1997-04-02 Mitsubishi Denki Kabushiki Kaisha Lampe à décharge et procédé de réalisation
US6858988B1 (en) * 2001-10-31 2005-02-22 Old Dominion University Research Foundation Electrodeless excimer UV lamp

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0766286A1 (fr) * 1991-05-31 1997-04-02 Mitsubishi Denki Kabushiki Kaisha Lampe à décharge et procédé de réalisation
US5146140A (en) * 1991-06-18 1992-09-08 Gte Products Corporation Method and apparatus to reduce Hg loss in rf capacitively coupled gas discharges
EP0593312A2 (fr) * 1992-10-16 1994-04-20 Flowil International Lighting (Holding) B.V. Source de lumière fluorescente
US6858988B1 (en) * 2001-10-31 2005-02-22 Old Dominion University Research Foundation Electrodeless excimer UV lamp

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102009059705A1 (de) * 2009-12-18 2011-06-22 Sick Maihak GmbH, 79183 Gasentladungslampe
US8482201B2 (en) 2009-12-18 2013-07-09 Sick Ag Gas discharge lamp

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Publication number Publication date
WO2008129481A3 (fr) 2009-01-29

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