EP0523782A2 - High-pressure sodium lamp - Google Patents
High-pressure sodium lamp Download PDFInfo
- Publication number
- EP0523782A2 EP0523782A2 EP92202047A EP92202047A EP0523782A2 EP 0523782 A2 EP0523782 A2 EP 0523782A2 EP 92202047 A EP92202047 A EP 92202047A EP 92202047 A EP92202047 A EP 92202047A EP 0523782 A2 EP0523782 A2 EP 0523782A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- winding
- lamp
- rod
- electrode
- pressure sodium
- 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.)
- Granted
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J61/00—Gas-discharge or vapour-discharge lamps
- H01J61/82—Lamps with high-pressure unconstricted discharge having a cold pressure > 400 Torr
- H01J61/825—High-pressure sodium lamps
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J61/00—Gas-discharge or vapour-discharge lamps
- H01J61/02—Details
- H01J61/04—Electrodes; Screens; Shields
- H01J61/06—Main electrodes
- H01J61/073—Main electrodes for high-pressure discharge lamps
- H01J61/0732—Main electrodes for high-pressure discharge lamps characterised by the construction of the electrode
Definitions
- the invention relates to a high-pressure sodium lamp which in the nominal operating condition radiates white light with a colour temperature higher than 2250 K, provided with a discharge vessel surrounding a discharge path and having a ceramic wall, in which vessel at least two electrodes are arranged, each electrode comprising a rod which has a diameter d, a length l, a tip, and is provided with a winding which is removed from the tip of the rod by a distance of at most 2d,the discharge path extending between said tips, while each electrode is connected to a current supply conductor which is passed in a gastight manner through the wall of the discharge vessel.
- Such a high-pressure sodium lamp is known from GB 2 083 692 A.
- ceramic wall is understood to mean in the present description and Claims a wall of a refractory material such as monocrystalline metal oxide, for example sapphire, polycrystalline metal oxide, for example densely sintered aluminium oxide or yttrium oxide, or crystalline non-oxidic material such as aluminium nitride.
- the filling of the discharge vessel may comprise, for example, mercury in addition to sodium and one or several rare gases.
- the winding consists, as does the rod of the electrode, of refractory material such as, for example, tungsten or, for example, an alloy of tungsten and rhenium.
- the area in the colour triangle within which the light of a high-pressure sodium lamp is called "white” is bounded by straight lines through points having coordinates (x, y): (0,400; 0,430), (0,510; 0,430), (0,485; 0,390) and (0,400; 0,360).
- the colour temperature may reach values of up to approximately 4000 K in that case.
- the known lamp consumes a power of 400 W during nominal operation.
- the electrode rods have a diameter of 1.2 mm and are provided with a double winding of wire with a diameter of 0.6 mm.
- the electrodes are free from alkaline earth metals.
- the electrodes are entirely devoid of emitter.
- the absence of emitter material has the advantage that chemical reactions with components of the filling are avoided and that the properties of the lamp during its life cannot change as a result of the gradual disappearance of emitter material from the electrode.
- the absence of emitter material in the electrode construction of the known lamp may result in a comparatively long ignition time and a wide spread in ignition times among lamps.
- ignition time is understood to mean the time required by the lamp for achieving a stable arc discharge via a glow discharge condition after the moment the ignition voltage is applied.
- a comparatively long ignition time is disadvantageous because the electrodes are highly loaded during lamp ignition, which in general adversely affects lamp life.
- a wide spread in ignition times has the disadvantage that the ambience is unevenly illuminated for some time after switching on of the lighting.
- the invention has for its object inter alia to provide a measure for avoiding the said disadvantages.
- a lamp of the hand mentioned in the opening paragraph is for this purpose characterized in that each of the windings is a single winding of wire having a diameter of at most d/3. Because of the absence of a second winding, the electrodes are easy to manufacture. The measure achieves a short ignition time, also in the absence of emitter material, as well as a small spread in the ignition times among lamps, especially for lamps whose discharge vessels contain Xe with a filling pressure of at least 20 kPa.
- the invention is particularly suitable for use in lamps with a power rating of up to 100 W.
- the winding preferably extends up to substantially the tip of the rod, the interspacing remaining between the tip and the winding being of the order of at most 100 ⁇ m.
- the result of the measure is found to be greatest when the winding is provided around the electrode rod with minimal pitch.
- the electrode of the lamp according to the invention has an effective thickness d e which is equal to the rod diameter d plus twice the thickness of the wire forming the winding. In the case of a greater interspacing, it is found that the discharge no longer strikes the winding in the nominal operating condition.
- the winding is preferably removed from the location where the current supply conductor is passed through the discharge vessel wall by at least 1 mm. It is prevented by this that the winding absorbs amalgam between the turns as a result of capillary action.
- the winding extends over the full length of the rod. This renders it possible to manufacture the electrode in a simple manner in that it is sawn off as a segment from a rod with wire coiled around it which is comparatively long compared with the electrode. The operation of providing the winding for each individual electrode is avoided in this way.
- I is the lamp current in A in the nominal operating condition and d e is the effective thickness of the electrode in mm.
- Fig. 1 shows a high-pressure sodium lamp which in the nominal operating condition radiates white light with a colour temperature of at least 2250 K.
- the lamp is provided with a discharge vessel 1 with a wall 2 of densely sintered aluminium oxide as the ceramic material, enclosing a discharge path.
- Two electrodes 10a, 10b are arranged in the discharge vessel 1.
- the electrodes 10a, 10b are each connected to a current supply conductor 20a, 20b which is passed in a gastight manner through the wall 2 of the discharge vessel 1.
- the discharge vessel 1 is provided with a filling consisting of 10 mg of an amalgam of sodium and mercury with a weight ratio of 15/40 and xenon with a filling pressure of 53 kPa.
- the discharge vessel 1 is accommodated in an outer bulb 30 which is provided with a lamp cap 40.
- the outer bulb 30 may be filled with an inert gas, for example with nitrogen.
- Fig. 2 shows an embodiment of an electrode 10a of the lamp of Fig. 1.
- the other electrode 10b has a similar construction.
- the electrode 10a is fixed on a niobium lead-through element which serves as the current supply conductor 20a.
- the current supply conductor is passed through the wall 2 of the discharge vessel 1 in a gastight manner via a seal 5a of melting ceramic through a tube 4a sintered into an end 3a of the discharge vessel 1.
- the tube 4a, the seal 5a of melting ceramic and the discharge vessel are depicted in longitudinal section here.
- the electrode 10a has a rod 11a with a diameter d and a length l (see Fig. 2), which has a tip 12a and is provided with a winding 13a.
- the rod 11a of the electrode 10a is provided with a single winding 13a of wire with a diameter of at most d/3.
- the winding 13a is removed from the tip 12a of the rod 11a by at most 2d.
- the length l of the rod is 7.2 mm and its thickness d is 500 ⁇ m.
- the winding is removed from the tip 12a by less than 0.1 mm ad extends from there alongside the rod 11a over a distance of 4 mm.
- the winding accordingly is approximately 3 mm removed from the location where the current supply conductor is passed through the wall of the discharge vessel.
- the spacing between the tips of the electrodes 10a, 10b is 9.6 mm.
- the winding 13a is made of tungsten wire of 100 ⁇ m thickness and has the smallest possible pitch, i.e. 100 ⁇ m.
- the effective thickness of the electrode is 700 ⁇ m as a result.
- the lamp current is 2.5 A during nominal operation.
- the ratio I/d e 3/2 therefore, is 4.27 and lies within the limits 2 and 5 recommended for this ratio.
- Fig. 3 which shows a second embodiment of an electrode of the lamp of Fig. 1
- parts corresponding to parts of Fig. 2 have reference numerals which are 100 higher.
- the winding 113a extends over the entire length of the rod 111a, and the current supply conductor 120a extends 1 mm into the discharge vessel. The winding, accordingly, is 1 mm removed from the location where the current supply conductor is passed through the wall of the discharge vessel.
- the ignition behaviour of lamps according to the invention was investigated.
- the supply circuit of the lamps consisted of a ballast with an electronic starter and an electronic control unit.
- the supply circuit yielded a rated maximum effective voltage of 108 V and, during ignition, pulses with a duration of 410 ns and an amplitude of approximately 3 kV.
- Out of 80 tested lamps according to the invention all had ignited within one minute.
- Lamps according to the invention were subjected to an endurance test. At the start and after 100, 500 and 1000 hours photometric characteristics such as luminous flux and colour temperature, and electrical characteristics such as lamp voltage and power, were measured. Average values of the test results are given in Table 1 for lamps provided with electrodes according to the first embodiment of the invention (A) and for lamps provided with electrodes according to the second embodiment (B).
- Table 1 is the time in hours (h)
- V la is the lamp voltage in V
- P la is the power consumed by the lamp in W
- ⁇ is the luminous flux in 1m
- ⁇ is the luminous efficacy in 1m/W
- T c is the colour temperature in K.
- the lamp according to the second embodiment has a comparatively high luminous efficacy compared with the lamp according to the first embodiment.
- Table 1 lamp t (h) V la (V) P la (W) ⁇ (1m) ⁇ (1m/W) T c (K) A 0 44.6 111.2 7013 63.1 2607 100 50.2 105.0 5416 51.7 2665 500 50.5 104.9 4892 46.7 2624 1000 50.4 103.6 4687 45.3 2596 B 0 43.5 112.3 7285 64.7 2586 100 49.0 106.5 5678 53.4 2645 500 49.4 106.0 5135 48.4 2591 1000 50.3 103.7 4703 45.4 2588
Landscapes
- Discharge Lamps And Accessories Thereof (AREA)
- Vessels And Coating Films For Discharge Lamps (AREA)
- Discharge Lamp (AREA)
Abstract
Description
- The invention relates to a high-pressure sodium lamp which in the nominal operating condition radiates white light with a colour temperature higher than 2250 K, provided with a discharge vessel surrounding a discharge path and having a ceramic wall, in which vessel at least two electrodes are arranged, each electrode comprising a rod which has a diameter d, a length l, a tip, and is provided with a winding which is removed from the tip of the rod by a distance of at most 2d,the discharge path extending between said tips, while each electrode is connected to a current supply conductor which is passed in a gastight manner through the wall of the discharge vessel.
- Such a high-pressure sodium lamp is known from
GB 2 083 692 A. The term "ceramic wall" is understood to mean in the present description and Claims a wall of a refractory material such as monocrystalline metal oxide, for example sapphire, polycrystalline metal oxide, for example densely sintered aluminium oxide or yttrium oxide, or crystalline non-oxidic material such as aluminium nitride. The filling of the discharge vessel may comprise, for example, mercury in addition to sodium and one or several rare gases. - The winding consists, as does the rod of the electrode, of refractory material such as, for example, tungsten or, for example, an alloy of tungsten and rhenium.
- The area in the colour triangle within which the light of a high-pressure sodium lamp is called "white" is bounded by straight lines through points having coordinates (x, y): (0,400; 0,430), (0,510; 0,430), (0,485; 0,390) and (0,400; 0,360). The colour temperature may reach values of up to approximately 4000 K in that case.
- The known lamp consumes a power of 400 W during nominal operation. The electrode rods have a diameter of 1.2 mm and are provided with a double winding of wire with a diameter of 0.6 mm. The electrodes are free from alkaline earth metals. Preferably, the electrodes are entirely devoid of emitter. The absence of emitter material has the advantage that chemical reactions with components of the filling are avoided and that the properties of the lamp during its life cannot change as a result of the gradual disappearance of emitter material from the electrode. The absence of emitter material in the electrode construction of the known lamp may result in a comparatively long ignition time and a wide spread in ignition times among lamps. The term "ignition time" is understood to mean the time required by the lamp for achieving a stable arc discharge via a glow discharge condition after the moment the ignition voltage is applied. A comparatively long ignition time is disadvantageous because the electrodes are highly loaded during lamp ignition, which in general adversely affects lamp life. In an ambience in which several lamps are arranged, a wide spread in ignition times has the disadvantage that the ambience is unevenly illuminated for some time after switching on of the lighting.
- The invention has for its object inter alia to provide a measure for avoiding the said disadvantages.
- According to the invention, a lamp of the hand mentioned in the opening paragraph is for this purpose characterized in that each of the windings is a single winding of wire having a diameter of at most d/3. Because of the absence of a second winding, the electrodes are easy to manufacture. The measure achieves a short ignition time, also in the absence of emitter material, as well as a small spread in the ignition times among lamps, especially for lamps whose discharge vessels contain Xe with a filling pressure of at least 20 kPa.
- There is evidence to suggest that the favourable effects of the measure according to the invention are caused by the fact that the winding around the rod has a favourable influence on the heat balance of the electrode both during lamp ignition and during nominal operation. It is suspected that the favourable ignition behaviour of the lamp according to the invention is realized in that the comparatively thin wire conducts only little heat in its longitudinal direction and thus quickly assumes a temperature required for nominal lamp operation upon being struck by the glow discharge arc, as a result of which the transition from the glow discharge to the arc discharge takes place. The heat transfer from the winding to the rod is still small at comparatively low temperatures because the substantially cylindrical wire is in contact with the rod over a comparatively small surface area. During nominal operation, on the other hand, when the rod and the winding assume temperatures of the order of 2400 to 2700 K, there is a good thermal coupling between the rod and the winding as a result of radiation.
- The invention is particularly suitable for use in lamps with a power rating of up to 100 W.
- In the lamp according to the invention, the winding preferably extends up to substantially the tip of the rod, the interspacing remaining between the tip and the winding being of the order of at most 100 µm.
- The result of the measure is found to be greatest when the winding is provided around the electrode rod with minimal pitch.
- Since the single winding of the comparatively thin wire is removed from the rod tip by at most 2d, it is found that the discharge still strikes the winding during nominal operation. The electrode of the lamp according to the invention has an effective thickness de which is equal to the rod diameter d plus twice the thickness of the wire forming the winding. In the case of a greater interspacing, it is found that the discharge no longer strikes the winding in the nominal operating condition.
- The winding is preferably removed from the location where the current supply conductor is passed through the discharge vessel wall by at least 1 mm. It is prevented by this that the winding absorbs amalgam between the turns as a result of capillary action.
- In an embodiment which is advantageous on account of a favourable manufacturing technology, the winding extends over the full length of the rod. This renders it possible to manufacture the electrode in a simple manner in that it is sawn off as a segment from a rod with wire coiled around it which is comparatively long compared with the electrode. The operation of providing the winding for each individual electrode is avoided in this way.
- A ratio I/de 3/2 above 2 and below 5 is clearly preferable for the effective thickness of the electrodes. In this expression, I is the lamp current in A in the nominal operating condition and de is the effective thickness of the electrode in mm.
- This and other aspects of the high-pressure sodium lamp according to the invention will be explained in more detail with reference to the drawing in which:
- Fig. 1 is an elevation of an embodiment of a high-pressure sodium lamp according to the invention,
- Fig. 2 shows an end of the discharge vessel of the lamp of Fig. 1 provided with an electrode according to a first embodiment, partly in elevation and partly in longitudinal section, and
- Fig. 3 shows an end of the discharge vessel of the lamp of Fig. 1 provided with an electrode according to a second embodiment, partly in elevation and partly in longitudinal section.
- It is noted that the lamp and the components are not drawn true to scale in the drawing.
- Fig. 1 shows a high-pressure sodium lamp which in the nominal operating condition radiates white light with a colour temperature of at least 2250 K. The lamp is provided with a
discharge vessel 1 with awall 2 of densely sintered aluminium oxide as the ceramic material, enclosing a discharge path. Twoelectrodes discharge vessel 1. Theelectrodes current supply conductor wall 2 of thedischarge vessel 1. Thedischarge vessel 1 is provided with a filling consisting of 10 mg of an amalgam of sodium and mercury with a weight ratio of 15/40 and xenon with a filling pressure of 53 kPa. Thedischarge vessel 1 is accommodated in anouter bulb 30 which is provided with alamp cap 40. Theouter bulb 30 may be filled with an inert gas, for example with nitrogen. - Fig. 2 shows an embodiment of an
electrode 10a of the lamp of Fig. 1. Theother electrode 10b has a similar construction. Theelectrode 10a is fixed on a niobium lead-through element which serves as thecurrent supply conductor 20a. The current supply conductor is passed through thewall 2 of thedischarge vessel 1 in a gastight manner via aseal 5a of melting ceramic through atube 4a sintered into an end 3a of thedischarge vessel 1. Thetube 4a, theseal 5a of melting ceramic and the discharge vessel are depicted in longitudinal section here. Theelectrode 10a has a rod 11a with a diameter d and a length l (see Fig. 2), which has a tip 12a and is provided with a winding 13a. The rod 11a of theelectrode 10a is provided with a single winding 13a of wire with a diameter of at most d/3. The winding 13a is removed from the tip 12a of the rod 11a by at most 2d. In a practical embodiment, the length l of the rod is 7.2 mm and its thickness d is 500 µm. In this practical embodiment, the winding is removed from the tip 12a by less than 0.1 mm ad extends from there alongside the rod 11a over a distance of 4 mm. The winding accordingly is approximately 3 mm removed from the location where the current supply conductor is passed through the wall of the discharge vessel. The spacing between the tips of theelectrodes - The lamp current is 2.5 A during nominal operation. The ratio I/de 3/2, therefore, is 4.27 and lies within the
limits 2 and 5 recommended for this ratio. - In Fig. 3, which shows a second embodiment of an electrode of the lamp of Fig. 1, parts corresponding to parts of Fig. 2 have reference numerals which are 100 higher. In this embodiment of the lamp, the winding 113a extends over the entire length of the
rod 111a, and thecurrent supply conductor 120a extends 1 mm into the discharge vessel. The winding, accordingly, is 1 mm removed from the location where the current supply conductor is passed through the wall of the discharge vessel. - The ignition behaviour of lamps according to the invention was investigated. The supply circuit of the lamps consisted of a ballast with an electronic starter and an electronic control unit. The supply circuit yielded a rated maximum effective voltage of 108 V and, during ignition, pulses with a duration of 410 ns and an amplitude of approximately 3 kV. Out of 80 tested lamps according to the invention, all had ignited within one minute. The average ignition time and the standard deviation of the ignition times of these lamps, of which 95% even had an ignition time shorter than 5 seconds, were 7.8 s and 12.0 s, respectively.
- Lamps according to the invention were subjected to an endurance test. At the start and after 100, 500 and 1000 hours photometric characteristics such as luminous flux and colour temperature, and electrical characteristics such as lamp voltage and power, were measured. Average values of the test results are given in Table 1 for lamps provided with electrodes according to the first embodiment of the invention (A) and for lamps provided with electrodes according to the second embodiment (B). In the Table, t is the time in hours (h), Vla is the lamp voltage in V, Pla is the power consumed by the lamp in W, φ is the luminous flux in 1m, η is the luminous efficacy in 1m/W, and Tc is the colour temperature in K. Up to approximately 500 hours of operation, the lamp according to the second embodiment has a comparatively high luminous efficacy compared with the lamp according to the first embodiment.
Table 1 lamp t (h) Vla (V) Pla (W) φ (1m) η (1m/W) Tc (K) A 0 44.6 111.2 7013 63.1 2607 100 50.2 105.0 5416 51.7 2665 500 50.5 104.9 4892 46.7 2624 1000 50.4 103.6 4687 45.3 2596 B 0 43.5 112.3 7285 64.7 2586 100 49.0 106.5 5678 53.4 2645 500 49.4 106.0 5135 48.4 2591 1000 50.3 103.7 4703 45.4 2588
Claims (4)
- A high-pressure sodium lamp which in the nominal operating condition radiates white light with a colour temperature higher than 2250 K, provided with a discharge vessel surrounding a discharge path and having a ceramic wall, in which vessel at least two electrodes are arranged, each electrode comprising a rod which has a diameter d, a length l, a tip, and is provided with a winding which is removed from the tip of the rod by a distance of at most 2d, the discharge path extending between said tips, while each electrode is connected to a current supply conductor which is passed in a gastight manner through the wall of the discharge vessel,
characterized in that each of the windings is a single winding of wire having a diameter of at most d/3. - A high-pressure sodium lamp as claimed in Claim 1, characterized in that the winding extends at least up to the tip.
- A high-pressure sodium lamp as claimed in Claim 1 or 2, characterized in that the winding is at least 1 mm removed from the location where the current supply conductor is passed through the wall of the discharge vessel.
- A high-pressure sodium lamp as claimed in Claim 1, 2 or 3, characterized in that the winding extends over the entire rod.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP91201820 | 1991-07-12 | ||
EP91201820 | 1991-07-12 |
Publications (3)
Publication Number | Publication Date |
---|---|
EP0523782A2 true EP0523782A2 (en) | 1993-01-20 |
EP0523782A3 EP0523782A3 (en) | 1993-02-10 |
EP0523782B1 EP0523782B1 (en) | 1995-10-04 |
Family
ID=8207774
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19920202047 Expired - Lifetime EP0523782B1 (en) | 1991-07-12 | 1992-07-07 | High-pressure sodium lamp |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP0523782B1 (en) |
JP (1) | JPH05190146A (en) |
DE (1) | DE69205228T2 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0639853B1 (en) * | 1993-08-16 | 1998-06-10 | Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH | High-pressure discharge lamp with ceramic discharge vessel |
EP1394838A2 (en) | 2002-08-30 | 2004-03-03 | Matsushita Electric Industrial Co., Ltd. | Metal vapor discharge lamp and lighting apparatus capable of stable maintenance of characteristics |
CN100576421C (en) * | 2002-08-30 | 2009-12-30 | 松下电器产业株式会社 | The metal vapour lamp and the lighting apparatus that can keep stability characteristic (quality) |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2497496A (en) * | 1943-01-15 | 1950-02-14 | Gen Electric | Electrode structure for electric discharge devices or lamps |
GB1024182A (en) * | 1963-01-30 | 1966-03-30 | Gen Electric Co Ltd | Improvements in or relating to high pressure electric discharge lamps |
GB2083692A (en) * | 1980-09-05 | 1982-03-24 | Philips Nv | High-pressure sodium vapour discharge lamp |
-
1992
- 1992-07-07 EP EP19920202047 patent/EP0523782B1/en not_active Expired - Lifetime
- 1992-07-07 DE DE1992605228 patent/DE69205228T2/en not_active Expired - Fee Related
- 1992-07-13 JP JP18528392A patent/JPH05190146A/en active Pending
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2497496A (en) * | 1943-01-15 | 1950-02-14 | Gen Electric | Electrode structure for electric discharge devices or lamps |
GB1024182A (en) * | 1963-01-30 | 1966-03-30 | Gen Electric Co Ltd | Improvements in or relating to high pressure electric discharge lamps |
GB2083692A (en) * | 1980-09-05 | 1982-03-24 | Philips Nv | High-pressure sodium vapour discharge lamp |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0639853B1 (en) * | 1993-08-16 | 1998-06-10 | Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH | High-pressure discharge lamp with ceramic discharge vessel |
EP1394838A2 (en) | 2002-08-30 | 2004-03-03 | Matsushita Electric Industrial Co., Ltd. | Metal vapor discharge lamp and lighting apparatus capable of stable maintenance of characteristics |
EP1394838A3 (en) * | 2002-08-30 | 2009-01-07 | Panasonic Corporation | Metal vapor discharge lamp and lighting apparatus capable of stable maintenance of characteristics |
CN100576421C (en) * | 2002-08-30 | 2009-12-30 | 松下电器产业株式会社 | The metal vapour lamp and the lighting apparatus that can keep stability characteristic (quality) |
Also Published As
Publication number | Publication date |
---|---|
DE69205228T2 (en) | 1996-05-02 |
JPH05190146A (en) | 1993-07-30 |
EP0523782B1 (en) | 1995-10-04 |
DE69205228D1 (en) | 1995-11-09 |
EP0523782A3 (en) | 1993-02-10 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CA1107344A (en) | Hid sodium lamp which incorporates a high pressure of xenon and a trigger starting electrode | |
US6031332A (en) | Metal halide lamp having specific filling | |
KR19990044549A (en) | High-pressure discharge lamp | |
US7423380B2 (en) | Metal halide lamp that has desired color characteristic and is prevented from non-lighting due to leakage of arc tube attributable to crack occurring at thin tube, and lighting apparatus adopting the metal halide lamp | |
JPWO2006088128A1 (en) | Ceramic metal halide lamp with rated lamp power of 450W or more | |
CN1151540C (en) | Metal halide lamp | |
US4864191A (en) | Rhenium-containing electrode for a high-pressure sodium discharge lamp | |
JP3701222B2 (en) | High pressure discharge lamp and high pressure discharge lamp system using the same | |
US3851207A (en) | Stabilized high intensity sodium vapor lamp | |
US5698948A (en) | Metal halide lamp with ceramic discharge vessel and magnesium in the fill to improve lumen maintenance | |
EP0607633B1 (en) | Electrodeless low-pressure discharge lamp | |
CA1194073A (en) | Intimate contact starting aid for arc lamps | |
JP2947958B2 (en) | High pressure discharge lamp | |
EP0523782B1 (en) | High-pressure sodium lamp | |
US7423379B2 (en) | High-pressure gas discharge lamp having tubular electrodes | |
US4910433A (en) | Emitterless SDN electrode | |
EP0244909A1 (en) | High-pressure sodium vapour discharge lamp | |
EP0812467B1 (en) | Low-pressure discharge lamp | |
US3634718A (en) | High-pressure gaseous discharge lamp including a starting electrode | |
JP4111570B2 (en) | High pressure discharge lamp and lighting device | |
EP0126503A1 (en) | High-pressure discharge lamp | |
US4924146A (en) | Unsaturated high-pressure sodium lamp | |
US6639361B2 (en) | Metal halide lamp | |
CA2089251C (en) | Flicker-suppressed, low-power, high-pressure discharge lamp | |
EP0159741A1 (en) | High-pressure sodium vapour discharge lamp |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
PUAL | Search report despatched |
Free format text: ORIGINAL CODE: 0009013 |
|
AK | Designated contracting states |
Kind code of ref document: A2 Designated state(s): BE DE FR GB IT NL |
|
AK | Designated contracting states |
Kind code of ref document: A3 Designated state(s): BE DE FR GB IT NL |
|
17P | Request for examination filed |
Effective date: 19930719 |
|
17Q | First examination report despatched |
Effective date: 19941010 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): BE DE FR GB IT NL |
|
REF | Corresponds to: |
Ref document number: 69205228 Country of ref document: DE Date of ref document: 19951109 |
|
ITF | It: translation for a ep patent filed |
Owner name: ING. C. GREGORJ S.P.A. |
|
ET | Fr: translation filed | ||
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: BE Effective date: 19960731 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
BERE | Be: lapsed |
Owner name: PHILIPS ELECTRONICS N.V. Effective date: 19960731 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Effective date: 19970201 |
|
NLV4 | Nl: lapsed or anulled due to non-payment of the annual fee |
Effective date: 19970201 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: CD |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 19990723 Year of fee payment: 8 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 19990727 Year of fee payment: 8 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 19990826 Year of fee payment: 8 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20000707 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 20000707 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20010330 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20010501 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED. Effective date: 20050707 |