CA1263138A - High-pressure mercury vapour discharge lamp - Google Patents
High-pressure mercury vapour discharge lampInfo
- Publication number
- CA1263138A CA1263138A CA000518015A CA518015A CA1263138A CA 1263138 A CA1263138 A CA 1263138A CA 000518015 A CA000518015 A CA 000518015A CA 518015 A CA518015 A CA 518015A CA 1263138 A CA1263138 A CA 1263138A
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- CA
- Canada
- Prior art keywords
- halide
- lamp
- discharge vessel
- discharge
- value
- 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.)
- Expired
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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
- H01J61/827—Metal halide arc lamps
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J61/00—Gas-discharge or vapour-discharge lamps
- H01J61/02—Details
- H01J61/30—Vessels; Containers
Landscapes
- Discharge Lamp (AREA)
- Discharge Lamps And Accessories Thereof (AREA)
- Spectrometry And Color Measurement (AREA)
- Portable Outdoor Equipment (AREA)
- Ladders (AREA)
- Vessels And Coating Films For Discharge Lamps (AREA)
Abstract
ABSTRACT:
"High-pressure mercury vapour discharge lamp".
High-pressure mercury vapour discharge lamp having a discharge vessel of gas-tight radiation transmitting ceramic material, provided with a filling comprising a rare gas, mercury, sodium halide and thallium halide.
The wall load (power consumption divided by the surface area of the outer wall of the discharge vessel) has a value of at least 25 W/cm2. The ratio between the effecti-ve internal diameter ID of the discharge vessel and the spacing EA between two electrodes has a value in the range of 0.4 ? ID/EA ? 0.9.
Fig.
"High-pressure mercury vapour discharge lamp".
High-pressure mercury vapour discharge lamp having a discharge vessel of gas-tight radiation transmitting ceramic material, provided with a filling comprising a rare gas, mercury, sodium halide and thallium halide.
The wall load (power consumption divided by the surface area of the outer wall of the discharge vessel) has a value of at least 25 W/cm2. The ratio between the effecti-ve internal diameter ID of the discharge vessel and the spacing EA between two electrodes has a value in the range of 0.4 ? ID/EA ? 0.9.
Fig.
Description
~L2Z~;313l5 PEIN 11 485 l 17-2-1986 "High-pressure mercury vapour discharge lamp".
The invention relates to a high-pressure mercury vapour discharge lamp having a given power consumption during operation, provided with a discharge vessel having a wall of gas-tight, radiation transmitting ceramic material, said discharge vessel enveloping a discharge space and being provided with an ionizable filling com-prising a rare gas, mercury, sodium halide and thallium halide, an electrode being disposed within said discharge vessel in the proximity of each of two end wall parts, the electrode tips facing each other being locat~d at a mutual distance EA.
A lamp of this type is known, for example, from rJnited States Patent Specification 3,363,133 showing a discharge vessel of ceramic material, namely densely si:ntered polycrystalline aluminium oxide. In addition to mercury and a halogen, the known lamp comprises one or more metals such as thallium and furthermore i~ may comprise an alkali metal, for example, sodium.
The addition of metal haLides, in most cases ~20~ metal iodides, to the ionisable filling of a high-pressure ; ~mercury vapour d scharge lamp is a step that has been used for quite some time in lamps havin~ a quartz glass dischar-ge vesselO Its object is to obtain a higher density of metal~at~ms in the discharge space by utilizing the greater 25~ volatility of the metal halides~as compared wit~ th~t of ; the metals themselves, and hence a areater contribution of the metals to ~e radiation emitted by the lamp. This ~results in an improvement of the relative luminous flux and parti~ularly also the colour renditlon of the~lamp.
Alkali metals such as sodium and lithium are used in a halide form because these metals themselves are too aggressive relative to the quartz glass wall of the dischar-:~ , ~ ~ ge vessel.
: :
' :: : :: . :. . . ~ ,- : - : .
~L~fi~13~3 PHN 11 ~85 -2- 17-~2-19~6 In lamps conta:i.ning metal halc1e -the hali~e pressure is cletermined by the temperature of th~ coldest spot Tlcp wi-thin the discharge v~ssel. The maximum admlsslbLe value of T~cp is limi-ted by the material of the discharge vessel. In -the case oE quartz glass discharge vessels Tkp may not be more than approximately 800C. It has al-ready been recognlzed at an early stage that the use of materials for the wall of ~e discharge vessel which can be subjected to a hlgher thermal load may lead to higher hallde pressures. Unlted States Patent Specification 3,234,421 already states the possibility ~ using densely sintered aluminium oxide as a material for the discharge vesselO
A halide filling which is frequently used in quartz glass lamps consi~s of the halides of thallium and sodium to which mostly indium halide is added. Experiments have shown that as compared with the quartz glass lamps an im-provement is o~tained concerning the relative luminous flux and also to a very slight extent the colour rendition if such a filling is used in a ceramic lamp vessel as stated in the above-mentioned United States Patent Specification 3,363,133. Such a lamp has, however, some great drawbacks, so that its practical use is not very well possible. In the first place the colour rendition is still insufficient for many uses and furthermore these lamps have among themselves a strong spread in their colour point and a variation thereof during their lifetime.
Secondly it is found that the colour point of these lamps is greatly dependent on variations in the power consumption ~30 of the lamp. These variations are the result of malns volt-age variations that cannot be avoided in practice.
Vnited States Patent Specification 3,334,261 mentions lamp fillings comprising halides of;rare earth metals. It has been found that lamps having a satisfactory colour rendition are possible particularly with Dy, Ho, Er, Tm and/or La. A drawback of these lamps is that they have a high colour temperature (4000 K or higher). For practical uses a lower colour temperature is often very .
~i3~
much desired. IE the colour temperature in -these lamps is to be decrea~ed, the use of sod:lum hali.de ls generally required which must be used in comparative].y larcJc quanti-ties~ This resul-ts in a great decrease o~ the contribution of the rare earth metals to the radiation emitted by the lamp so that the colour rendition of the lamp is adversely affected.
It is an object of the invention to provide lamps with which hoth a high relative luminous flux and a satis-factory colour rendition are obtained in the low range ofcolour temperatures (approximate].y 2600-4000 K).
According to the invention a lamp of the type described in the opening paragraph is characterized in that the wall load, defined as the quotient of power consumption and outer surface area of the part of the wall of the discharge vesse]. located between the electrode tips, has a value of at least 25 W/cm2, in that the ratio between the effective internal di.ameter ID of the discharge vessel and EA has a value in the range of 0.4 ~ ID/EA C 0.9, ID heing defined as the square root of the quotient of the volume of the discharge space between the electrode tips and EA, and in that the ratio between the largest internal diameter ~if the discharge vessel and EA is at most equal to 1.1.
25 : : The invention is based on the recognition of the : fact that a satisfactory colour rendition~is possib].e when sodium halide is used in the filIing of a lamp if during ;~ : operation of the lamp there is a strong broadening and reversal of the emission of the sodium in the Na-D lines which:are located at 589.0 and 589.6 nm at ve.ry low : partial Na-pressures. By broadening and reversal the Na-D
lines~assume the shape of emission bands, the short-wave : band being shifted to shorter wavelengths:and the :
long-wave band being shifted to longer wavelengths as the emission is more reversed. A measure of the reversal is therefore the distance ~ ~ in nm between ~he maximum ~:~ values of the Na-emi.ssion bands. The long-wave emission ~ : band of the Na i9 shifted to the red part of the spectrum~
: '.
: - - : : . : - . :................................. ..
, , ...................... :.:. .: . .
.
~G~3 !3 PHN 11 ~85 -~- 17~-19~6 which is very favourable for the col.our rendition proper-ties. It has been found that a better colour rencli,tion, that is to say, a h.~gl1er val.ue oE -the average colour renderi,ng :Lnclex Ra8 ls obtai.ned as ~ ~ has a higher value.
The colour rendering inclex Eor deep red colours, ~9, which is often negative to deeply negative in di,scharge lamps may assume positive values in lamps according to the inventi,on if ~ ~ is relati.vely high. The value of ~A at which given colour rendition properties are obtained is still dependent on the lamp type and the lamp filling. Thus, in lamps having a low power consumption (for example, less than 100 W) lower values of ~ ~ may generally suffice to obtain the same colour rendition properties as in lamps having a higher power consumption, because a higher mercury pressure prevails in these low-power lamps so that an increasing Van der Waals broadening is an extra contri-bution, predominantly to the long~wave side of the Na-D
lines.
It has been found that two conditions are to be : 20 fulfilled for a strong broadening and reversal of the Na-D
: l.ines. In the first place a large contribution of Na-D
emission is required. This involves a high sodium halide pressure and hence a high temperature of the coldest spot : Tkp in the discharge vessel, for example, 300C or more.
This requirement for Tkp e~cludes the use of quartz glass for the discharge vessel. In a lamp according to the invention a gas-tight, radiation transmitting ceramic material is therefore used for the wall of the discharge vessel. A very suitable material is aluminium o~ide which is 3~ usable in a densely sintered polycrystalline form and a].so in a monocrystalline form (sapphire). Other possible materials are, for example, densely sintered yttrium oxide and yttrium aluminium garnet. The said high values of Tkp are attained in a lamp according to the invention by : ~ 35 dimensioning the discharge vessel for a given power consumption during operation in such a manner that the wall load has a value of at least 25 W/cm . The wall load is defined as the quotient of power consumption and surface :, ,: ,; , ,, ~' , ' , . :
,: , , , " ., , ~ . . : .
'' ~
.
3~
PHN 11 485 -5- 18-2~1986 area oE the discharge vessel, cons.Lder:Lng only ~.hat part of the outer surface area of the discharge vessel that is loca-ted between the electrode tips.
The second conditi.on which is to be fulfilled to obtain a sufficiently high ~ ~ is that the actual discharge arc in the discharge vessel is to ke surrounded with a sufficiently thick layer of Na-atoms in the fundamental state. I`his means that the discharge vesse]. must fulfil given geometrical requirements, notably a relatively wi.de discharge vessel is necessary. In a lamp according to the invention the ratio between the effective internal diameter ID of the discharge vessel and the electrode distance EA
has a value in the range of 0,.4 ~ ID/EA ~ O.9. ID is herein understood to mean the square root of the quotient of the volume of the discharge space between the electrode tips and EA. It has been found that also in ].amps having a discharge vessel deviating from the cylindrical shape a thick shell of Na-atoms in the fundamental stat.e is formed around the discharge arc such that a strong reversal of the Na-D lines i5 possible if the ahove-rnentioned condition of ID/EA is fulfilled. A lamp as shown in the United States Patent Specification 3,363,133 already referred t.o above ~has ah ID/EA value of approximate~y~.0~,25. It has : ~ been found that for ID/EA values of less than 0.4 a :
too small ~ ~ is obtained and therefore a too low Ra8 : value. ID/EA values of more than 0.9 are not used be-cause at such values Tkp easily assumes a too low value.
Experiments have also shown that a further condition is to be imposed as regards the largest internal. diameter 0i :
~: 30 for Iamps having a strongly curved wall surface o~ the : discharge vessel, far example, ellipsoidal, spherical or approximately spherical lamp vessels. In fact, the ratio between 0i and EA must be not more than 1.1 because~a too low Tkp is obtained: at higher values, even if the con-dition for ID/EA is satisfied. For cylindrical discharge : vessels ID is substantially equa:l to 0.89 0i so that the condition for 0i/EA is always satisfied if the con-dition for ID/EA lS satisfied.
,, : :
., , . ~ .
~;3~.3~
PE-IN l1 ~85 6- 17-2-19~6 In a preferred embodiment ,llof a lamp accordi.ng to the invention the distance between the electrode -tips and the adjacent end wall parts of the discharge vessel is not more ~han hal:E the largest internal diameter (~0i) In that case the required high value of the tempera-ture of the co].dest spot in the lamp can more easily be attained, generally also without extra steps for heat insu].ation of the lamp extremiti.es.
The lamps according to the invention have the advantage that for agiven filling they have only a little spread in the colour point of the emitted radiation and also a very sma].l variation of the colour point during their lifetime. A great advantage of these lamps is that they do not substantially show any colour variation when varying the supplied power within fairly ample limits. It has been found that the effects of variations in the power counteract each other, in a sense, as a result of the relatively high sodium pressure and the lamp geometry used, so that a colour point st.abilisation is obtained.
For the quantity of mercury which is used in the lamps according to the invention considera-tions apply that are analogous to the known metal halide-containing high-pressure mercury vapour discharge lamps. Generally the mercury quantity is mainly determined by t~e arc voltage desired in the lamp. The mercury quantity will fre~uen~ly : be relatively low for lamps having a high power (for ; ~ example at least 1 mg per cm3 o the discharge space at powers of the order of 2000 W) and will increase with a decreasing power (to, for example 100 mg per cm at powers of the order of 10 W~.
The filling of the lamps according to the in-vention comprises halides, preferably iodides, of sodium and of; thallium. The sodium halide is present in~excess, that is to say, unevaporated sodium halide is still ~ 35 present during operation of the lamp. In practical lamps the : sodium halide quantity is generally at least 10 /u mol per cm3 of the discharge space (for lamps having a higher : ~ power) and assumes larger values as the power decreases .
.: . ... . .
~G3~L3~3 PHN 11 ~85 -7- 17-2-1986 (for example, to 500 /umol per cm3 for the smallest lamps).
In the lamps the thallium halide contributes in the form of the predominantly green thallium radiation so that white or substantially white light can be obtained in combination with the sodium radiation. Lamps are preferred which are characterized in that the molar ratio between thallium halide and sodium halide is at least 0.05 and at most 0.25. The lamps according to this pEeferred embodiment emit light at a comparati.vely low colour tempera-ture, which is very much desirable for certain uses(for example, lighting for the living room and decorative lighting). The colour temperature is dependent on the Tl:Na ratio chosen and has values of approximately 2500 K
(colour point slightl~ below the line of the black radiators and h.aving a slightly yellow colour aspect) to approximately 3000 K (colour point slightly above the line of the klack radiators and having a slightly green colour aspect). Lamps having a colour pcint which is substantially on the line of the black radiat.ors have a colour temperature of approxi-mately 2700 K.
A further advantageous embodiment of a lamp accord-ing to the invention is characterized in that the discharge vessel further comprises at least one halide of a metal radiating substantially in the blue or purple part of the spectrumr which halide, compared with sodium halide, has a hi~h volatility ~nd i.n which the molar ratio between th~ halide and the halides of Na and Tl combined has a val.ue of up to 0.1 at a maximum. The use of blue or purple radiators provides the possibility of obtaining lamps hav-ing a higher colour temperature of the emitted radiation(higher than approximately 2700 K). To maintain sat.isfa tory colour rendition properties, it is required for the halide of the blue or purple radiator to be used in relatively small quantities because otherwise the sodium halide is too much diluted so that ~ ~ would be adversely affected.
Therefore volatile halides are chosen (saturated vapour pressure at 900C at least. a factor of 10 larger than that of sodium iodide) in which the molar ratio between these halides and the halide of Na and Tl combined is not - , `'' .,.~ ; ' ~3~3~
Pl-IN 11 ~85 -~- 17-2-1986 more than 0.1 and preferably of the order of 0.01. In this manner lamps can be obtained havlng a hicJh e~ficlency, a satisfactory colour rendition and a colour -temperature of up to approxima-tely 3200 K. Lamps of this type are preferred which comprise at least one halide of at least one of the elements In, Sn and Cd because the best results are achieved with these halides.
A further preferred embodiment of a lamp accord-ing to the invention is characterized in that the di~charge vessel also comprises at least one halide of at least one of the elements Sc, La and the lanthanides, in which the molar ratio between these halides and the halides of Na and Tl combined has a value of at least 0.02. The said elements Sc, La and the lanthanides have an emission consisting of many lines distributed over the entire spectrum with the centre generally being in the blue part of the spectrum so that these elements, if used only in a lamp, yield a colour point of the emitted radiation of 5000 K. Consequently, with the lamps of this embodiment as compared with the lamps comprising only Na and Tl higher colour temperatures can be attained whilst main-taining high luminous fluxes and very satisactary colour rendition properties. Values of the molar ratio be-tween the halides of Sc, La and/or lanthanide and the hali-des of Na and Tl combined are then chosen to be at least0.02 because then generally colour temperatures are attained of at least 3000 K. In fact, for colour tempera-tures of less than 3000 K the embodiments described herein-before with volatile, blue radiators are found to be more advantageous. In these lamps having a colour tempera-ture of 3000 K or more the use of at least one halide of at least of one of the elements Dy, Tm, Ho Er and La is preferred. With Dy lamps can be obtained having very high values of Ra8 and Rg and with colour temperatures of up to approximately 3600 K. The molar ratio between dysprosium halide and sodium and thallium halide is then preferably 0.03 or more. With one or more of the elements Tm, Ho, Er an~ La it is possible to make lamps having colour tempe-.. . . ~, .
~`
: .
6~3~;3~3 PHN 11 485 ~9~ 17-2-1986 rat~lres of up to approximately ~500 K, where -the molar ratlo between the halides of these lanthclnides and the sodium and -thallium halide is preferably chosen to be 0.04 or more.
Embodiments of lamps according to the ~vention will now be further described with reference to the accompanying drawing and a number of measurements.
The drawing shows in a cross-section a high-press-ure mercury vapour discharge lamp according to the invention, intended for a power consumption of 160 W.
In the drawing the reference numeral 1 denotes the discharge vessel of a lamp according to the invention hav-ing a nominal power of 160 W. The discharge vessel 1 has a cylindrical wall part 2 of densely sintered polycrystal-line alumini~lm o~ide having a total length of 19 mm, anexternal diameter of 8.45 mm and an internal diameter of 6 85 mm. End wall parts 3, 4 and 5, 6, likewise of densely sintered aluminium oxide are sintered in a gas-tight manner to the respective ends of the part 2. These end wall parts consist of discs 3 an~ 5 having a thickness of 2 mm and projecting tubes 4 and 6, respectively. The projecting portion of the tubes 4~ 6 has a length of 8 mm, an external diameter of 3 mm and an internal diameter of 2.05 mm. Tungsten pins 7 and 8 having a diameter of 0.2 mm are sealed in the tubes 4, 6, respectively, to-gether with aluminium oxide pack:ing pieces 17 and 18, ;~; respectively with the aid of~ a halide-resistant melting glass denoted by the reference numerals 9 and 10, respective-ly. The ends of the pins 7, 8 located inside the discharge vessel 1 constitute electrodes 11 and 12, respectively, ;~ with the tips 13 and 14 facing each other and are provided with tungsten electrode filaments 15 and 16, respectively (2 layers, 5 turns each o~ wire having a diameter of 0.3 mm).
The distance EA between the tips 13 and 14 is 10 mm. The effective internal diameter~ID of the discharge vessel 1 is 6.07 mm. The ratio ID/EA is therefore 0.6. (The largest internal diameter ~i is 6.85 mm and thus 0i/EA =
0.685). The dlstance between the electrode tips 13 and 14 ''~
. ~ ., .. .. . , - , . :
: ' . --" ~ '' . ' ' :
~Z~i3~3~s and the ell~ wall parts 3, ~ and 5, 6, respectively, is
The invention relates to a high-pressure mercury vapour discharge lamp having a given power consumption during operation, provided with a discharge vessel having a wall of gas-tight, radiation transmitting ceramic material, said discharge vessel enveloping a discharge space and being provided with an ionizable filling com-prising a rare gas, mercury, sodium halide and thallium halide, an electrode being disposed within said discharge vessel in the proximity of each of two end wall parts, the electrode tips facing each other being locat~d at a mutual distance EA.
A lamp of this type is known, for example, from rJnited States Patent Specification 3,363,133 showing a discharge vessel of ceramic material, namely densely si:ntered polycrystalline aluminium oxide. In addition to mercury and a halogen, the known lamp comprises one or more metals such as thallium and furthermore i~ may comprise an alkali metal, for example, sodium.
The addition of metal haLides, in most cases ~20~ metal iodides, to the ionisable filling of a high-pressure ; ~mercury vapour d scharge lamp is a step that has been used for quite some time in lamps havin~ a quartz glass dischar-ge vesselO Its object is to obtain a higher density of metal~at~ms in the discharge space by utilizing the greater 25~ volatility of the metal halides~as compared wit~ th~t of ; the metals themselves, and hence a areater contribution of the metals to ~e radiation emitted by the lamp. This ~results in an improvement of the relative luminous flux and parti~ularly also the colour renditlon of the~lamp.
Alkali metals such as sodium and lithium are used in a halide form because these metals themselves are too aggressive relative to the quartz glass wall of the dischar-:~ , ~ ~ ge vessel.
: :
' :: : :: . :. . . ~ ,- : - : .
~L~fi~13~3 PHN 11 ~85 -2- 17-~2-19~6 In lamps conta:i.ning metal halc1e -the hali~e pressure is cletermined by the temperature of th~ coldest spot Tlcp wi-thin the discharge v~ssel. The maximum admlsslbLe value of T~cp is limi-ted by the material of the discharge vessel. In -the case oE quartz glass discharge vessels Tkp may not be more than approximately 800C. It has al-ready been recognlzed at an early stage that the use of materials for the wall of ~e discharge vessel which can be subjected to a hlgher thermal load may lead to higher hallde pressures. Unlted States Patent Specification 3,234,421 already states the possibility ~ using densely sintered aluminium oxide as a material for the discharge vesselO
A halide filling which is frequently used in quartz glass lamps consi~s of the halides of thallium and sodium to which mostly indium halide is added. Experiments have shown that as compared with the quartz glass lamps an im-provement is o~tained concerning the relative luminous flux and also to a very slight extent the colour rendition if such a filling is used in a ceramic lamp vessel as stated in the above-mentioned United States Patent Specification 3,363,133. Such a lamp has, however, some great drawbacks, so that its practical use is not very well possible. In the first place the colour rendition is still insufficient for many uses and furthermore these lamps have among themselves a strong spread in their colour point and a variation thereof during their lifetime.
Secondly it is found that the colour point of these lamps is greatly dependent on variations in the power consumption ~30 of the lamp. These variations are the result of malns volt-age variations that cannot be avoided in practice.
Vnited States Patent Specification 3,334,261 mentions lamp fillings comprising halides of;rare earth metals. It has been found that lamps having a satisfactory colour rendition are possible particularly with Dy, Ho, Er, Tm and/or La. A drawback of these lamps is that they have a high colour temperature (4000 K or higher). For practical uses a lower colour temperature is often very .
~i3~
much desired. IE the colour temperature in -these lamps is to be decrea~ed, the use of sod:lum hali.de ls generally required which must be used in comparative].y larcJc quanti-ties~ This resul-ts in a great decrease o~ the contribution of the rare earth metals to the radiation emitted by the lamp so that the colour rendition of the lamp is adversely affected.
It is an object of the invention to provide lamps with which hoth a high relative luminous flux and a satis-factory colour rendition are obtained in the low range ofcolour temperatures (approximate].y 2600-4000 K).
According to the invention a lamp of the type described in the opening paragraph is characterized in that the wall load, defined as the quotient of power consumption and outer surface area of the part of the wall of the discharge vesse]. located between the electrode tips, has a value of at least 25 W/cm2, in that the ratio between the effective internal di.ameter ID of the discharge vessel and EA has a value in the range of 0.4 ~ ID/EA C 0.9, ID heing defined as the square root of the quotient of the volume of the discharge space between the electrode tips and EA, and in that the ratio between the largest internal diameter ~if the discharge vessel and EA is at most equal to 1.1.
25 : : The invention is based on the recognition of the : fact that a satisfactory colour rendition~is possib].e when sodium halide is used in the filIing of a lamp if during ;~ : operation of the lamp there is a strong broadening and reversal of the emission of the sodium in the Na-D lines which:are located at 589.0 and 589.6 nm at ve.ry low : partial Na-pressures. By broadening and reversal the Na-D
lines~assume the shape of emission bands, the short-wave : band being shifted to shorter wavelengths:and the :
long-wave band being shifted to longer wavelengths as the emission is more reversed. A measure of the reversal is therefore the distance ~ ~ in nm between ~he maximum ~:~ values of the Na-emi.ssion bands. The long-wave emission ~ : band of the Na i9 shifted to the red part of the spectrum~
: '.
: - - : : . : - . :................................. ..
, , ...................... :.:. .: . .
.
~G~3 !3 PHN 11 ~85 -~- 17~-19~6 which is very favourable for the col.our rendition proper-ties. It has been found that a better colour rencli,tion, that is to say, a h.~gl1er val.ue oE -the average colour renderi,ng :Lnclex Ra8 ls obtai.ned as ~ ~ has a higher value.
The colour rendering inclex Eor deep red colours, ~9, which is often negative to deeply negative in di,scharge lamps may assume positive values in lamps according to the inventi,on if ~ ~ is relati.vely high. The value of ~A at which given colour rendition properties are obtained is still dependent on the lamp type and the lamp filling. Thus, in lamps having a low power consumption (for example, less than 100 W) lower values of ~ ~ may generally suffice to obtain the same colour rendition properties as in lamps having a higher power consumption, because a higher mercury pressure prevails in these low-power lamps so that an increasing Van der Waals broadening is an extra contri-bution, predominantly to the long~wave side of the Na-D
lines.
It has been found that two conditions are to be : 20 fulfilled for a strong broadening and reversal of the Na-D
: l.ines. In the first place a large contribution of Na-D
emission is required. This involves a high sodium halide pressure and hence a high temperature of the coldest spot : Tkp in the discharge vessel, for example, 300C or more.
This requirement for Tkp e~cludes the use of quartz glass for the discharge vessel. In a lamp according to the invention a gas-tight, radiation transmitting ceramic material is therefore used for the wall of the discharge vessel. A very suitable material is aluminium o~ide which is 3~ usable in a densely sintered polycrystalline form and a].so in a monocrystalline form (sapphire). Other possible materials are, for example, densely sintered yttrium oxide and yttrium aluminium garnet. The said high values of Tkp are attained in a lamp according to the invention by : ~ 35 dimensioning the discharge vessel for a given power consumption during operation in such a manner that the wall load has a value of at least 25 W/cm . The wall load is defined as the quotient of power consumption and surface :, ,: ,; , ,, ~' , ' , . :
,: , , , " ., , ~ . . : .
'' ~
.
3~
PHN 11 485 -5- 18-2~1986 area oE the discharge vessel, cons.Lder:Lng only ~.hat part of the outer surface area of the discharge vessel that is loca-ted between the electrode tips.
The second conditi.on which is to be fulfilled to obtain a sufficiently high ~ ~ is that the actual discharge arc in the discharge vessel is to ke surrounded with a sufficiently thick layer of Na-atoms in the fundamental state. I`his means that the discharge vesse]. must fulfil given geometrical requirements, notably a relatively wi.de discharge vessel is necessary. In a lamp according to the invention the ratio between the effective internal diameter ID of the discharge vessel and the electrode distance EA
has a value in the range of 0,.4 ~ ID/EA ~ O.9. ID is herein understood to mean the square root of the quotient of the volume of the discharge space between the electrode tips and EA. It has been found that also in ].amps having a discharge vessel deviating from the cylindrical shape a thick shell of Na-atoms in the fundamental stat.e is formed around the discharge arc such that a strong reversal of the Na-D lines i5 possible if the ahove-rnentioned condition of ID/EA is fulfilled. A lamp as shown in the United States Patent Specification 3,363,133 already referred t.o above ~has ah ID/EA value of approximate~y~.0~,25. It has : ~ been found that for ID/EA values of less than 0.4 a :
too small ~ ~ is obtained and therefore a too low Ra8 : value. ID/EA values of more than 0.9 are not used be-cause at such values Tkp easily assumes a too low value.
Experiments have also shown that a further condition is to be imposed as regards the largest internal. diameter 0i :
~: 30 for Iamps having a strongly curved wall surface o~ the : discharge vessel, far example, ellipsoidal, spherical or approximately spherical lamp vessels. In fact, the ratio between 0i and EA must be not more than 1.1 because~a too low Tkp is obtained: at higher values, even if the con-dition for ID/EA is satisfied. For cylindrical discharge : vessels ID is substantially equa:l to 0.89 0i so that the condition for 0i/EA is always satisfied if the con-dition for ID/EA lS satisfied.
,, : :
., , . ~ .
~;3~.3~
PE-IN l1 ~85 6- 17-2-19~6 In a preferred embodiment ,llof a lamp accordi.ng to the invention the distance between the electrode -tips and the adjacent end wall parts of the discharge vessel is not more ~han hal:E the largest internal diameter (~0i) In that case the required high value of the tempera-ture of the co].dest spot in the lamp can more easily be attained, generally also without extra steps for heat insu].ation of the lamp extremiti.es.
The lamps according to the invention have the advantage that for agiven filling they have only a little spread in the colour point of the emitted radiation and also a very sma].l variation of the colour point during their lifetime. A great advantage of these lamps is that they do not substantially show any colour variation when varying the supplied power within fairly ample limits. It has been found that the effects of variations in the power counteract each other, in a sense, as a result of the relatively high sodium pressure and the lamp geometry used, so that a colour point st.abilisation is obtained.
For the quantity of mercury which is used in the lamps according to the invention considera-tions apply that are analogous to the known metal halide-containing high-pressure mercury vapour discharge lamps. Generally the mercury quantity is mainly determined by t~e arc voltage desired in the lamp. The mercury quantity will fre~uen~ly : be relatively low for lamps having a high power (for ; ~ example at least 1 mg per cm3 o the discharge space at powers of the order of 2000 W) and will increase with a decreasing power (to, for example 100 mg per cm at powers of the order of 10 W~.
The filling of the lamps according to the in-vention comprises halides, preferably iodides, of sodium and of; thallium. The sodium halide is present in~excess, that is to say, unevaporated sodium halide is still ~ 35 present during operation of the lamp. In practical lamps the : sodium halide quantity is generally at least 10 /u mol per cm3 of the discharge space (for lamps having a higher : ~ power) and assumes larger values as the power decreases .
.: . ... . .
~G3~L3~3 PHN 11 ~85 -7- 17-2-1986 (for example, to 500 /umol per cm3 for the smallest lamps).
In the lamps the thallium halide contributes in the form of the predominantly green thallium radiation so that white or substantially white light can be obtained in combination with the sodium radiation. Lamps are preferred which are characterized in that the molar ratio between thallium halide and sodium halide is at least 0.05 and at most 0.25. The lamps according to this pEeferred embodiment emit light at a comparati.vely low colour tempera-ture, which is very much desirable for certain uses(for example, lighting for the living room and decorative lighting). The colour temperature is dependent on the Tl:Na ratio chosen and has values of approximately 2500 K
(colour point slightl~ below the line of the black radiators and h.aving a slightly yellow colour aspect) to approximately 3000 K (colour point slightly above the line of the klack radiators and having a slightly green colour aspect). Lamps having a colour pcint which is substantially on the line of the black radiat.ors have a colour temperature of approxi-mately 2700 K.
A further advantageous embodiment of a lamp accord-ing to the invention is characterized in that the discharge vessel further comprises at least one halide of a metal radiating substantially in the blue or purple part of the spectrumr which halide, compared with sodium halide, has a hi~h volatility ~nd i.n which the molar ratio between th~ halide and the halides of Na and Tl combined has a val.ue of up to 0.1 at a maximum. The use of blue or purple radiators provides the possibility of obtaining lamps hav-ing a higher colour temperature of the emitted radiation(higher than approximately 2700 K). To maintain sat.isfa tory colour rendition properties, it is required for the halide of the blue or purple radiator to be used in relatively small quantities because otherwise the sodium halide is too much diluted so that ~ ~ would be adversely affected.
Therefore volatile halides are chosen (saturated vapour pressure at 900C at least. a factor of 10 larger than that of sodium iodide) in which the molar ratio between these halides and the halide of Na and Tl combined is not - , `'' .,.~ ; ' ~3~3~
Pl-IN 11 ~85 -~- 17-2-1986 more than 0.1 and preferably of the order of 0.01. In this manner lamps can be obtained havlng a hicJh e~ficlency, a satisfactory colour rendition and a colour -temperature of up to approxima-tely 3200 K. Lamps of this type are preferred which comprise at least one halide of at least one of the elements In, Sn and Cd because the best results are achieved with these halides.
A further preferred embodiment of a lamp accord-ing to the invention is characterized in that the di~charge vessel also comprises at least one halide of at least one of the elements Sc, La and the lanthanides, in which the molar ratio between these halides and the halides of Na and Tl combined has a value of at least 0.02. The said elements Sc, La and the lanthanides have an emission consisting of many lines distributed over the entire spectrum with the centre generally being in the blue part of the spectrum so that these elements, if used only in a lamp, yield a colour point of the emitted radiation of 5000 K. Consequently, with the lamps of this embodiment as compared with the lamps comprising only Na and Tl higher colour temperatures can be attained whilst main-taining high luminous fluxes and very satisactary colour rendition properties. Values of the molar ratio be-tween the halides of Sc, La and/or lanthanide and the hali-des of Na and Tl combined are then chosen to be at least0.02 because then generally colour temperatures are attained of at least 3000 K. In fact, for colour tempera-tures of less than 3000 K the embodiments described herein-before with volatile, blue radiators are found to be more advantageous. In these lamps having a colour tempera-ture of 3000 K or more the use of at least one halide of at least of one of the elements Dy, Tm, Ho Er and La is preferred. With Dy lamps can be obtained having very high values of Ra8 and Rg and with colour temperatures of up to approximately 3600 K. The molar ratio between dysprosium halide and sodium and thallium halide is then preferably 0.03 or more. With one or more of the elements Tm, Ho, Er an~ La it is possible to make lamps having colour tempe-.. . . ~, .
~`
: .
6~3~;3~3 PHN 11 485 ~9~ 17-2-1986 rat~lres of up to approximately ~500 K, where -the molar ratlo between the halides of these lanthclnides and the sodium and -thallium halide is preferably chosen to be 0.04 or more.
Embodiments of lamps according to the ~vention will now be further described with reference to the accompanying drawing and a number of measurements.
The drawing shows in a cross-section a high-press-ure mercury vapour discharge lamp according to the invention, intended for a power consumption of 160 W.
In the drawing the reference numeral 1 denotes the discharge vessel of a lamp according to the invention hav-ing a nominal power of 160 W. The discharge vessel 1 has a cylindrical wall part 2 of densely sintered polycrystal-line alumini~lm o~ide having a total length of 19 mm, anexternal diameter of 8.45 mm and an internal diameter of 6 85 mm. End wall parts 3, 4 and 5, 6, likewise of densely sintered aluminium oxide are sintered in a gas-tight manner to the respective ends of the part 2. These end wall parts consist of discs 3 an~ 5 having a thickness of 2 mm and projecting tubes 4 and 6, respectively. The projecting portion of the tubes 4~ 6 has a length of 8 mm, an external diameter of 3 mm and an internal diameter of 2.05 mm. Tungsten pins 7 and 8 having a diameter of 0.2 mm are sealed in the tubes 4, 6, respectively, to-gether with aluminium oxide pack:ing pieces 17 and 18, ;~; respectively with the aid of~ a halide-resistant melting glass denoted by the reference numerals 9 and 10, respective-ly. The ends of the pins 7, 8 located inside the discharge vessel 1 constitute electrodes 11 and 12, respectively, ;~ with the tips 13 and 14 facing each other and are provided with tungsten electrode filaments 15 and 16, respectively (2 layers, 5 turns each o~ wire having a diameter of 0.3 mm).
The distance EA between the tips 13 and 14 is 10 mm. The effective internal diameter~ID of the discharge vessel 1 is 6.07 mm. The ratio ID/EA is therefore 0.6. (The largest internal diameter ~i is 6.85 mm and thus 0i/EA =
0.685). The dlstance between the electrode tips 13 and 14 ''~
. ~ ., .. .. . , - , . :
: ' . --" ~ '' . ' ' :
~Z~i3~3~s and the ell~ wall parts 3, ~ and 5, 6, respectively, is
2.5 mm. The conten-ts of the vessel I are 0.55 cm3.
For a power oE 160 W the wall load~oE this lamp l~s 60 W/cm~.
The discharge space within the vessel 1 contains an ionisable filling comprising mercury, argon as an ignition gas and halides. The discharge vessel 1 of the lamp is generally built in an outer envelope (not shown in the drawing).
A ]amp having a construction as shown in the drawing was provided with 12 mg of mercury (approximately 21.8 mg Hg per cm3 contents of the discharge vesse]) and argon up to a pressure of 200 mbar. The lamp also con-tained 9.2 mg of a mixture of sodium iodide and thallium iodide, with the molar ratio between Na and Tl having a value of Na:Tl = 92.5:7.5. During operation of the lamp a relative luminous flux of 93 lm/W was measured at a power consumption of 160 W. The coordinates of the colour point of the emitted radiation were x = 0.465 and y = 0O403 and :
the colour temperature T had a value of 2565 K. For the -average colour rendering index RaB a value of 8~ was found and for the colour rendering index R9 a value of +20 was found. The distance between the maximum values of the Na emission bands, ~ ~ , was found to be 145 nm. Variation in the power consumption o~the lamp proved to have little influence on the colour point. At a power of 150 W x was 0.466 and y was 0-404 (Tc = 2560 K) and at a power of 175 W x was 0.464 and y was 0-403 (Tc = 2570 K).
EP~IPLES 2 to 10.
Nine lamps having the same construc~ion as the lamp of Example 1 were provided with an iodide mixture which in addition to the iodides-of Na and Tl also contain-ed an iodide of a blue radia~or (indium, lanthanum or a lanthanide). Likewise as the lamp of Example 1 these lamps were provided with 1~ mg of mercury, with the except-35 ion of Example 2 (10.1 mg Hg) and Example ~ (10 mg Hg).
The following Table states for each Example the total mass M of the iodide mixture, the blue radiator used and the molar ratio of the iodides. Furthermore the Table , :
. .
~2G3~38 PHN 11 485 -11- l7-2-l986 s-ta-tes for each lamp the results o:~ measurement.s at a power consump-tion of 150 W. The relative ].urninous :~lux ~ (ln/W), the colour point x,y, the colour temperature Tc (K), the colour renderin~ indices Ra8 and R9, and the distance ~ ~ (nm) were measured.
:~ 25 : : :
~ 30 ::
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PHN 11 4 85 -12- 17-2-1 9~S
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PHN 11 485 -13 '17-2-1986 A lamp having a construction as shown in the draw-ing, but intended for a power of 110 W was manufactured.
The lamp had an external diameter of 6.0 mr~l, a (laryest) internal diameter of 4.8 mm ~effective internal diameter ID = 4 . 25 mm~ and an electrode distance EA of 8 mrn. The ratio ID/EA was therefore 0. 53 . The end wall parts consisted of a disc having a thickness of 3 mm and a projecting tube having an external diameter of 3 mm ~length projecting portion 7 mm). The distance between the electrode tips and the respective end wall parts was 1. 5 mm. The contents of the discharge vessel were 0.20 cm3. At a power of 110 W
the wall load was 73 W/cm2. The lamp was provided with 5 mg of mercury (25 mg Hg per cm3) and argon up to a pressure f 200 mbarO Furthermore 4.9 grams of a mixture of sodium iodide and thallium iodide (molar ratio Na:Tl = 92.8:7.2) was added to the filling. A relative luminous flux ~ = 88 lm/W, chromaticity coordinates x = 0.444 and y = 0.414, colour temperature TC = 2970 K, Ra8 = 84, P~g = -19 and A ~ = 91 nm, were measured on the lamp.
EXAMPLES 12 and 13.
Two lamps having a construction analogous to that of the lamp shown in the drawing, but intended for a power consumption of 40 W were manufactured. The external diameter f these lamps was 4.4 mm, the llargest) internal diameter was 3.5 mm (ID = 3.1 mm) and the electrode distance EA was 3.5 mm. The value of ID/EA thus was 0.69. The end wall parts had a disc having a thickness of 3 mm and a projecting tube having an external diameter of 2 mm (le`ngth projecting portion 3 mm). The distance between electrode tip and end waIl part was 1.25 mm. The contents of the discharge vessel were 0.0S8 cm3. At a power of 40 W
the wall load was 82 W/cm2. The lamps were provided with argon up to a pressure of 800 tnbar, with mercury (Example 1 2 : 2.89 mg: Example 13: 3.63 mg), and with a mixture of iodides of Na, Tl and In. The lamp of Example 12 contained 2 . 4 mg of this mixture in the molar ratio Na:Tl:In =
84.95:14.50:0.54. The lamp of Example 13 contained .., : .
:
. ~, .
'. : :`:
~L2~3~
PHN 11 485 -14- 17-~2-1986 2.74 mg of -this m:Lxture in the molar ratio Na:Tl:In =
80.80:i8.67:0.52. The followlng measurements were made at a power consumption oE 40 W:
lExampl~ ample 13 ~-tlm~/w) r78.5 70 x 1Ø441 10.436 y '0.378 ~0.399 Tc (K) ~2715 !2965 a8 ,89 192 Rg .24 ¦47 ~ ~(nm) ,129 ¦141 : ~5 3n `` ~
;
For a power oE 160 W the wall load~oE this lamp l~s 60 W/cm~.
The discharge space within the vessel 1 contains an ionisable filling comprising mercury, argon as an ignition gas and halides. The discharge vessel 1 of the lamp is generally built in an outer envelope (not shown in the drawing).
A ]amp having a construction as shown in the drawing was provided with 12 mg of mercury (approximately 21.8 mg Hg per cm3 contents of the discharge vesse]) and argon up to a pressure of 200 mbar. The lamp also con-tained 9.2 mg of a mixture of sodium iodide and thallium iodide, with the molar ratio between Na and Tl having a value of Na:Tl = 92.5:7.5. During operation of the lamp a relative luminous flux of 93 lm/W was measured at a power consumption of 160 W. The coordinates of the colour point of the emitted radiation were x = 0.465 and y = 0O403 and :
the colour temperature T had a value of 2565 K. For the -average colour rendering index RaB a value of 8~ was found and for the colour rendering index R9 a value of +20 was found. The distance between the maximum values of the Na emission bands, ~ ~ , was found to be 145 nm. Variation in the power consumption o~the lamp proved to have little influence on the colour point. At a power of 150 W x was 0.466 and y was 0-404 (Tc = 2560 K) and at a power of 175 W x was 0.464 and y was 0-403 (Tc = 2570 K).
EP~IPLES 2 to 10.
Nine lamps having the same construc~ion as the lamp of Example 1 were provided with an iodide mixture which in addition to the iodides-of Na and Tl also contain-ed an iodide of a blue radia~or (indium, lanthanum or a lanthanide). Likewise as the lamp of Example 1 these lamps were provided with 1~ mg of mercury, with the except-35 ion of Example 2 (10.1 mg Hg) and Example ~ (10 mg Hg).
The following Table states for each Example the total mass M of the iodide mixture, the blue radiator used and the molar ratio of the iodides. Furthermore the Table , :
. .
~2G3~38 PHN 11 485 -11- l7-2-l986 s-ta-tes for each lamp the results o:~ measurement.s at a power consump-tion of 150 W. The relative ].urninous :~lux ~ (ln/W), the colour point x,y, the colour temperature Tc (K), the colour renderin~ indices Ra8 and R9, and the distance ~ ~ (nm) were measured.
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__ . ______ __ c~) c~ D ~ I~ O N
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PHN 11 485 -13 '17-2-1986 A lamp having a construction as shown in the draw-ing, but intended for a power of 110 W was manufactured.
The lamp had an external diameter of 6.0 mr~l, a (laryest) internal diameter of 4.8 mm ~effective internal diameter ID = 4 . 25 mm~ and an electrode distance EA of 8 mrn. The ratio ID/EA was therefore 0. 53 . The end wall parts consisted of a disc having a thickness of 3 mm and a projecting tube having an external diameter of 3 mm ~length projecting portion 7 mm). The distance between the electrode tips and the respective end wall parts was 1. 5 mm. The contents of the discharge vessel were 0.20 cm3. At a power of 110 W
the wall load was 73 W/cm2. The lamp was provided with 5 mg of mercury (25 mg Hg per cm3) and argon up to a pressure f 200 mbarO Furthermore 4.9 grams of a mixture of sodium iodide and thallium iodide (molar ratio Na:Tl = 92.8:7.2) was added to the filling. A relative luminous flux ~ = 88 lm/W, chromaticity coordinates x = 0.444 and y = 0.414, colour temperature TC = 2970 K, Ra8 = 84, P~g = -19 and A ~ = 91 nm, were measured on the lamp.
EXAMPLES 12 and 13.
Two lamps having a construction analogous to that of the lamp shown in the drawing, but intended for a power consumption of 40 W were manufactured. The external diameter f these lamps was 4.4 mm, the llargest) internal diameter was 3.5 mm (ID = 3.1 mm) and the electrode distance EA was 3.5 mm. The value of ID/EA thus was 0.69. The end wall parts had a disc having a thickness of 3 mm and a projecting tube having an external diameter of 2 mm (le`ngth projecting portion 3 mm). The distance between electrode tip and end waIl part was 1.25 mm. The contents of the discharge vessel were 0.0S8 cm3. At a power of 40 W
the wall load was 82 W/cm2. The lamps were provided with argon up to a pressure of 800 tnbar, with mercury (Example 1 2 : 2.89 mg: Example 13: 3.63 mg), and with a mixture of iodides of Na, Tl and In. The lamp of Example 12 contained 2 . 4 mg of this mixture in the molar ratio Na:Tl:In =
84.95:14.50:0.54. The lamp of Example 13 contained .., : .
:
. ~, .
'. : :`:
~L2~3~
PHN 11 485 -14- 17-~2-1986 2.74 mg of -this m:Lxture in the molar ratio Na:Tl:In =
80.80:i8.67:0.52. The followlng measurements were made at a power consumption oE 40 W:
lExampl~ ample 13 ~-tlm~/w) r78.5 70 x 1Ø441 10.436 y '0.378 ~0.399 Tc (K) ~2715 !2965 a8 ,89 192 Rg .24 ¦47 ~ ~(nm) ,129 ¦141 : ~5 3n `` ~
;
Claims (7)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A high-pressure mercury vapour discharge lamp having a given power consumption during operation, pro-vided with a discharge vessel having a wall of gas-tight, radiation transmitting ceramic material, said discharge vessel enveloping a discharge space and being provided with an ionisable filling comprising a rare gas, mercury, sodium halide and thallium halide, an electrode being disposed within said discharge vessel in the proximity of each of two end wall parts, the electrode tips facing each other being located at a mutual distance EA, charac-terized in that the wall load, defined as the quotient of power consumption and outer surface area of the part of the wall of the discharge vessel located between the elec-trode tips has a value of at least 25 W/cm2, in that the ratio between the effective internal diameter ID of the discharge vessel and EA has a value in the range of 0.4 ?ID/EA ? 0.9, ID being defined as the square root of the quotient of the volume of the discharge space between the electrode tips and EA, and in that the ratio between the largest internal diameter ?i of the discharge vessel and EA is at most equal to 1.1.
2. A lamp as claimed in Claim 1, characterized in that the distance between the electrode tips and the adjacent end wall parts of the discharge vessel is not more than ? ?i.
3. A lamp as claimed in Claim 1 or 2, characterized in that the molar ratio between the thallium halide and the sodium halide is at least 0.05 and at most 0.25.
4. A lamp as claimed in Claim 1, characterized in that the discharge vessel furthermore contains at least one halide of a metal radiating substantially in the blue or purple part of the spectrum, said halide, compared with sodium halide, having a high volatility and the molar ratio between said halide and the halides of Na and T1 combined having a value of not more than 0.1.
5. A lamp as claimed in Claim 4, characterized in that the discharge vessel contains at least one halide of at least one of the elements In, Sn and Cd.
6. A lamp as claimed in Claim 1, characterized in that the discharge vessel furthermore contains at least one halide of at least one of the elements Sc, La and the lanthanides, the molar ratio between said halides and the halides of Na and T1 combined having a value of at least 0.02.
7. A lamp as claimed in Claim 6, characterized in that the dsicharge vessel contains at least one halide of at least one of the elements Dy, Tm, Ho, Er and La.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL8502509 | 1985-09-13 | ||
| NL8502509A NL8502509A (en) | 1985-09-13 | 1985-09-13 | HIGH PRESSURE MERCURY DISCHARGE LAMP. |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1263138A true CA1263138A (en) | 1989-11-21 |
Family
ID=19846551
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000518015A Expired CA1263138A (en) | 1985-09-13 | 1986-09-11 | High-pressure mercury vapour discharge lamp |
Country Status (13)
| Country | Link |
|---|---|
| EP (1) | EP0215524B1 (en) |
| JP (1) | JPS6266556A (en) |
| CN (1) | CN1008030B (en) |
| AT (1) | ATE45056T1 (en) |
| AU (1) | AU6258586A (en) |
| BR (1) | BR8604319A (en) |
| CA (1) | CA1263138A (en) |
| DD (1) | DD249567A5 (en) |
| DE (1) | DE3664701D1 (en) |
| ES (1) | ES2005822A6 (en) |
| FI (1) | FI863659A (en) |
| HU (1) | HU194442B (en) |
| NL (1) | NL8502509A (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB8707670D0 (en) * | 1987-03-31 | 1987-05-07 | Emi Plc Thorn | Ceramic metal halide lamps |
| KR0167339B1 (en) * | 1989-02-07 | 1999-01-15 | 스루오 스토무 | Metal halide lamp |
| DE4013039A1 (en) * | 1990-04-24 | 1991-10-31 | Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh | HIGH PRESSURE DISCHARGE LAMP |
| EP0494310A4 (en) * | 1990-07-18 | 1992-11-19 | Toto Ltd. | Variable color lamp |
| DE4132530A1 (en) * | 1991-09-30 | 1993-04-01 | Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh | HIGH PRESSURE DISCHARGE LAMP WITH LOW POWER |
| CN1069148C (en) * | 1994-04-13 | 2001-08-01 | 皇家菲利浦电子有限公司 | High-pressure metal halide lamp |
| CA2164973A1 (en) * | 1994-04-13 | 1995-10-26 | Nancy Jean Caruso | Metal halide lamp |
| CA2226556A1 (en) * | 1996-05-09 | 1997-11-13 | Philips Electronics N.V. | High-pressure discharge lamp |
| TW343348B (en) * | 1996-12-04 | 1998-10-21 | Philips Electronics Nv | Metal halide lamp |
| CN100377286C (en) * | 1997-04-09 | 2008-03-26 | 皇家菲利浦电子有限公司 | Metal halide lamp |
| EP0910866B1 (en) | 1997-04-25 | 2004-06-23 | Koninklijke Philips Electronics N.V. | High-pressure discharge lamp |
| DE19727430A1 (en) * | 1997-06-27 | 1999-01-07 | Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh | Metal halide lamp with ceramic discharge tube |
| EP0931330B1 (en) * | 1997-07-23 | 2003-08-13 | Koninklijke Philips Electronics N.V. | Mercury free metal halide lamp |
| JP4316699B2 (en) | 1997-07-25 | 2009-08-19 | ハリソン東芝ライティング株式会社 | High pressure discharge lamp and lighting device |
| US6137229A (en) * | 1997-09-26 | 2000-10-24 | Matsushita Electronics Corporation | Metal halide lamp with specific dimension of the discharge tube |
| US6147453A (en) | 1997-12-02 | 2000-11-14 | U.S. Philips Corporation | Metal-halide lamp with lithium and cerium iodide |
| JP3318250B2 (en) | 1997-12-26 | 2002-08-26 | 松下電器産業株式会社 | Metal vapor discharge lamp |
| TW385479B (en) | 1998-04-08 | 2000-03-21 | Koninkl Philips Electronics Nv | Metal-halide lamp |
| CN1364307A (en) * | 1999-01-28 | 2002-08-14 | 皇家菲利浦电子有限公司 | Metal halide lamp |
| CN1171279C (en) * | 1999-04-29 | 2004-10-13 | 皇家菲利浦电子有限公司 | Metal halide lamp |
| CN1171283C (en) * | 1999-08-25 | 2004-10-13 | 皇家菲利浦电子有限公司 | Metal halide lamp |
| US6882109B2 (en) * | 2000-03-08 | 2005-04-19 | Japan Storage Battery Co., Ltd. | Electric discharge lamp |
| US6650056B2 (en) * | 2001-12-21 | 2003-11-18 | Koninklijke Philips Electronics N.V. | Stabilizing short-term color temperature in a ceramic high intensity discharge lamp |
| US7245081B2 (en) | 2003-03-03 | 2007-07-17 | Osram-Melco Toshiba Lighting Ltd. | High-intensity discharge lamp with particular metal halide gas filling and lighting device |
| WO2005029534A2 (en) * | 2003-09-22 | 2005-03-31 | Koninklijke Philips Electronics N.V. | Metal halide lamp |
| CN1906732A (en) * | 2003-10-10 | 2007-01-31 | 皇家飞利浦电子股份有限公司 | High pressure discharge lamp |
| EP1807861A2 (en) * | 2004-10-26 | 2007-07-18 | Koninklijke Philips Electronics N.V. | Metal halide lamp |
| GB2420220B (en) | 2004-11-10 | 2009-10-14 | Gen Electric | Ceramic metal halide lamps |
| US7279838B2 (en) | 2005-03-09 | 2007-10-09 | General Electric Company | Discharge tubes |
| US7211954B2 (en) | 2005-03-09 | 2007-05-01 | General Electric Company | Discharge tubes |
| EP1869694A2 (en) * | 2005-04-08 | 2007-12-26 | Koninklijke Philips Electronics N.V. | High-pressure discharge lamp |
| JP2006310185A (en) * | 2005-04-28 | 2006-11-09 | Osram Melco Toshiba Lighting Kk | Metal vapor discharge lamp |
| US7474057B2 (en) | 2005-11-29 | 2009-01-06 | General Electric Company | High mercury density ceramic metal halide lamp |
| EP2054920B1 (en) | 2006-08-18 | 2015-06-24 | Koninklijke Philips N.V. | Metal halide lamp |
| JP5069493B2 (en) * | 2006-11-02 | 2012-11-07 | ハリソン東芝ライティング株式会社 | UV discharge lamp |
| WO2008068666A2 (en) | 2006-12-01 | 2008-06-12 | Koninklijke Philips Electronics N.V. | Metal halide lamp |
| EP2140479A2 (en) | 2007-04-20 | 2010-01-06 | Koninklijke Philips Electronics N.V. | Metal halide lamp comprising a shaped ceramic discharge vessel |
| US8227991B2 (en) | 2007-04-20 | 2012-07-24 | Koninklijke Philips Electronics N.V. | Metal halide lamp comprising an ionisable salt filling |
| CN102113085A (en) | 2008-08-06 | 2011-06-29 | 皇家飞利浦电子股份有限公司 | Metal halide lamp |
| DE202010018034U1 (en) | 2009-09-10 | 2013-08-27 | Koninklijke Philips N.V. | High pressure discharge lamp |
| WO2011121492A2 (en) | 2010-04-02 | 2011-10-06 | Koninklijke Philips Electronics N.V. | Metal halide lamp |
| US9093257B2 (en) | 2011-05-06 | 2015-07-28 | Koninklijke Philips N.V. | Sealing compound and ceramic discharge vessel comprising such sealing compound |
| WO2015191031A1 (en) | 2014-06-09 | 2015-12-17 | Halliburton Energy Services, Inc. | Tungsten-halogen electromagnetic radiation optical systems source |
| GB201809481D0 (en) * | 2018-06-08 | 2018-07-25 | Ceravision Ltd | A plasma light source |
| GB201809479D0 (en) * | 2018-06-08 | 2018-07-25 | Ceravision Ltd | A plasma light source |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL7005294A (en) * | 1970-04-13 | 1971-10-15 | ||
| DE2114804B2 (en) * | 1971-03-26 | 1978-09-14 | Patent-Treuhand-Gesellschaft Fuer Elektrische Gluehlampen Mbh, 8000 Muenchen | Mercury vapor high pressure discharge lamp with the addition of rare earth halides |
| NL184550C (en) * | 1982-12-01 | 1989-08-16 | Philips Nv | GAS DISCHARGE LAMP. |
-
1985
- 1985-09-13 NL NL8502509A patent/NL8502509A/en not_active Application Discontinuation
-
1986
- 1986-09-10 ES ES8601743A patent/ES2005822A6/en not_active Expired
- 1986-09-10 EP EP86201561A patent/EP0215524B1/en not_active Expired
- 1986-09-10 DE DE8686201561T patent/DE3664701D1/en not_active Expired
- 1986-09-10 HU HU863906A patent/HU194442B/en unknown
- 1986-09-10 BR BR8604319A patent/BR8604319A/en unknown
- 1986-09-10 CN CN86106082A patent/CN1008030B/en not_active Expired
- 1986-09-10 JP JP61211791A patent/JPS6266556A/en active Pending
- 1986-09-10 AT AT86201561T patent/ATE45056T1/en not_active IP Right Cessation
- 1986-09-10 FI FI863659A patent/FI863659A/en not_active Application Discontinuation
- 1986-09-10 DD DD86294304A patent/DD249567A5/en not_active IP Right Cessation
- 1986-09-11 AU AU62585/86A patent/AU6258586A/en not_active Abandoned
- 1986-09-11 CA CA000518015A patent/CA1263138A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| FI863659A0 (en) | 1986-09-10 |
| CN1008030B (en) | 1990-05-16 |
| HU194442B (en) | 1988-01-28 |
| DD249567A5 (en) | 1987-09-09 |
| BR8604319A (en) | 1987-05-05 |
| ATE45056T1 (en) | 1989-08-15 |
| NL8502509A (en) | 1987-04-01 |
| FI863659A (en) | 1987-03-14 |
| HUT42203A (en) | 1987-06-29 |
| JPS6266556A (en) | 1987-03-26 |
| EP0215524B1 (en) | 1989-07-26 |
| DE3664701D1 (en) | 1989-08-31 |
| EP0215524A1 (en) | 1987-03-25 |
| AU6258586A (en) | 1987-03-19 |
| ES2005822A6 (en) | 1989-04-01 |
| CN86106082A (en) | 1987-06-03 |
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| Date | Code | Title | Description |
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| MKLA | Lapsed |