EP0670588A1 - Metallhalogenidlampe - Google Patents

Metallhalogenidlampe Download PDF

Info

Publication number
EP0670588A1
EP0670588A1 EP94301523A EP94301523A EP0670588A1 EP 0670588 A1 EP0670588 A1 EP 0670588A1 EP 94301523 A EP94301523 A EP 94301523A EP 94301523 A EP94301523 A EP 94301523A EP 0670588 A1 EP0670588 A1 EP 0670588A1
Authority
EP
European Patent Office
Prior art keywords
moles
halide lamp
metal
bromine
iodine
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
Application number
EP94301523A
Other languages
English (en)
French (fr)
Other versions
EP0670588B1 (de
Inventor
Kouji Kawai
Shigeki Ishihara
Naoki Masuda
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hamamatsu Photonics KK
Original Assignee
Hamamatsu Photonics KK
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to JP4256287A priority Critical patent/JPH06111769A/ja
Application filed by Hamamatsu Photonics KK filed Critical Hamamatsu Photonics KK
Priority to DE1994603190 priority patent/DE69403190T2/de
Priority to EP94301523A priority patent/EP0670588B1/de
Publication of EP0670588A1 publication Critical patent/EP0670588A1/de
Application granted granted Critical
Publication of EP0670588B1 publication Critical patent/EP0670588B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J61/00Gas-discharge or vapour-discharge lamps
    • H01J61/02Details
    • H01J61/12Selection of substances for gas fillings; Specified operating pressure or temperature
    • H01J61/18Selection of substances for gas fillings; Specified operating pressure or temperature having a metallic vapour as the principal constituent
    • H01J61/20Selection of substances for gas fillings; Specified operating pressure or temperature having a metallic vapour as the principal constituent mercury vapour

Definitions

  • the present invention generally relates to a metal halide lamp and, more particularly, to contents which are contained in a hermetically sealed tube of a metal halide lamp.
  • a metal halide lamp is a lamp in which a metal halide is added in a sealed tube, in which mercury vapor is contained at a high pressure, to improve the luminous efficacy and color rending properties, and is widely used for general illumination.
  • a conventional metal halide lamp is fabricated by charging, in a light-transmitting quartz tube, an inert gas, e.g., argon (Ar), at least one kind of halide (LnX2 or LnX3: where Ln is a rare earth metal, e.g., scandium (Sc), yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium
  • tungsten (W) as the base material of electrodes is liberated by sputtering during use, and free tungsten reacts with silicon dioxide (SiO2) as a constituent component of the sealed tube to deposit on the inner wall surface of the sealed tube, thereby blackening the tube wall within a short period of time. Blackening of the tube wall decreases the luminous efficacy and lumen maintenance factor. When the lumen maintenance factor decreases to about 70%, the metal halide lamp becomes inappropriate for practical use.
  • the present invention has been made in view of the above situation, and the object of the present invention is to provide a long-life metal halide lamp which can prevent blackening of the tube wall.
  • a metal halide lamp comprising a sealed tube, a pair of electrodes made of tungsten as a base material and arranged to oppose each other in the sealed tube, and contents of the sealed tube and including an inert gas, mercury, a rare earth metal, bromine, and iodine, wherein the total number of moles of bromine and iodine is in excess of the number of moles of the rare earth metal.
  • the total number of moles of bromine and iodine must be in excess of the total number of moles of the rare earth metals.
  • Excess here means that when bromine and iodine react with all the rare earth metals, bromine or iodine that does not react with the rare earth metals remains. Accordingly, even when tungsten is emitted from the electrodes during electric discharge, it can be captured by iodine or bromine.
  • Fig. 1 is a view of a metal halide lamp according to an embodiment of the present invention, and shows the principle of function of the present invention.
  • This metal halide lamp has a transparent quartz sealed tube and a pair of electrodes using tungsten as the base material. The respective electrodes are mounted on the sealed tube with hermetically passing through the wall surface of the sealed tube. The inner end portions of these electrodes are opposed to each other.
  • Argon (Ar), a rare earth metal (Ln), mercury (Hg), cesium (Cs), iodine (I), and bromine (Br) are contained in the sealed tube.
  • these contents are charged in the tube in the form of atoms or compounds. More specifically, bromides of the rare earth metal (LnBr2 and LnBr3), mercury iodide (HgI2), cesium iodide (CsI), argon gas, and mercury are charged in the tube during the manufacture.
  • the amounts of bromine and iodine are in excess of the amount of rare earth metals.
  • Fig. 1 when arc discharge is started between a pair of opposed electrodes 2 and 3 which are made of tungsten as the base material, mainly in a high-temperature (2,000°C or more) area near the electrodes 2 and 3, most of the contents are ionized. Tungsten of the electrodes 2 and 3 is also emitted from the electrodes 2 and 3 by sputtering and is ionized.
  • bromine or iodine are recombined with cesium, and bromine or iodine are also recombined with rare earth metal. Further, mercury and tungsten are set in the atomic state. The excesses of bromine and iodine which are not recombined with the rare earth metal and cesium are also set in the atomic state. Since bromine has a higher reactivity than iodine, bromine is combined with cesium and rare earth metal before iodine is combined therewith. Therefore, in this medium-temperature area, most of the halogens in the atomic state are iodine.
  • a medium-temperature a range of 1,000°C or more to less than 2,000°C
  • tungsten tends to be combined with iodine. Unlike bromine, even when iodine is combined with mercury, it is quickly separated from mercury. When the amounts of free tungsten and iodine are sufficient with respect to each other, all tungsten atoms are captured by halogens, mainly iodine. Therefore, tungsten will not react with silicon dioxide which is an element constituting the sealed tube. Thereafter, the materials produced in the low-temperature area are circulated in a cycle indicated by arrows due to heat convection.
  • Tungsten iodides WI2, WI3 and WI4
  • halides of rare earth metal LnX2 and LnX3
  • silicon dioxide the low-temperature area
  • these products do not highly react with silicon dioxide, a long period of time is required until the tube wall is blackened to such a degree that the sealed tube is inappropriate for practical use.
  • free tungsten can be captured mainly by iodine and set in the halogen cycle, so that the effect of suppressing blackening of the tube wall is much enhanced.
  • a preferable condition of "excess" described above is expressed by a relation of numbers of moles as follows: [M(Br) + M(I)]/M(Ln) > 3 where M(Br) is the number of moles of bromine atoms, M(I) is the number of moles of iodine atoms, and M(Ln) is the number of moles of rare earth metal atoms.
  • Fig. 2 is a view showing the principle of a case wherein bromine is not added at all and only an excess of iodine is charged in a sealed tube.
  • iodine is combined with the rare earth metal, cesium and tungsten.
  • the iodide of the rare earth metal is combined less than the bromide of the rare earth metal, substitution reaction of the rare earth metal with silicon dioxide of the sealed tube often occurs.
  • the rare earth metal tends to deposit on the inner wall surface of the sealed tube, thereby decreasing the service life when compared to a case wherein bromine is contained in the sealed tube.
  • M(Br)/M(Ln) ⁇ 1 The upper limit of the above value is preferably 3 from the results of various experiments. More specifically, 3 ⁇ M(Br)/M(Ln) ⁇ 1 Examples of the present invention will be described.
  • a rugby-ball like spherical quartz sealed tube having a major axis of 25 mm, a minor axis of 21 mm, an internal volume of 3.2 cc, and an interelectrode distance of 7 mm was used.
  • Argon gas was contained as an initiating inert gas, and the pressure in the sealed tube was set to 50 to 300 torr (6.65 to 39.9 kPa).
  • the electrodes were made of tungsten as the base material. Cesium was contained to prevent flickering of the lamp.
  • the present invention is not intended to be limited to the above-mentioned size or pressure, etc.
  • Table 1 indicates the compositions, electrical characteristics, optical characteristics, and the like of the contents (excluding argon) of Examples 1 to 9 according to the present invention.
  • two or more kinds of rare earth metals appropriately selected from dysprosium (Dy), holmium (Ho), thulium (Tm), neodymium (Nd) and erbium (Er); an alkali metal, i.e., cesium (Cs); iodine (I); bromine (Br); and mercury (Hg) were contained in the sealed tube to satisfy the relations (2) and (4).
  • the rare earth metals and the alkali metal were charged in the form of iodides or bromides in Examples 1 to 9.
  • the electrical characteristics indicate the initial value
  • the lumen maintenance factor of the optical characteristics is a proportion of the value of the luminous flux at a lapse of a predetermined period of time with respect to the initial value of the luminous flux at the central area on the screen when light was projected from the metal halide lamp of each example which is mounted in an overhead projector.
  • x represented a case wherein the lumen maintenance factor was less than 70% before the lapse of 48 hours since the start of light emission
  • represented a case wherein the lumen maintenance factor was 70% or more at the lapse of 48 hours but was less than 70% at the lapse of 500 hours
  • o represented a case wherein the lumen maintenance factor was between 70% or more and less than 80% at the lapse of 500 hours
  • o represented a case wherein the lumen maintenance factor was 80% or more at the lapse of 500 hours.
  • Example 1 As is understood from Table 1, it is apparent that in any of Examples 1 to 9, a high lumen maintenance factor was maintained over a long period of time, and blackening of the tube wall was prevented. Especially, in Example 1 wherein 10.75 x 10 ⁇ 6 mole of rare earth metals (dysprosium, holmium, and thulium), 0.51 x 10 ⁇ 6 mole of cesium, 32.76 x 10 ⁇ 6 mole of iodine, and 27.75 x 10 ⁇ 6 mole of bromine were contained in the sealed tube, the lumen maintenance factor was maintained at 90% over 1,000 hours and 85% after 1,630 hours, thereby obtaining an excellent result.
  • rare earth metals disprosium, holmium, and thulium
  • the preferable condition is as follows: 3 ⁇ M(Br)/M(Ln) ⁇ 2, and [M(Br) + M(I) - M(NA)]/M(Ln) > 4.5
  • the further preferable condition is as follows: 2.95 ⁇ M(Br)/M(Ln) ⁇ 2.2, and [M(Br) + M(I) - M(NA)]/M(Ln) > 4.6
  • the value of [M(Br) + M(I) - M(NA)]/M(Ln) may be more than 3.
  • Samples 1 to 4 of Table 2 exhibit the performance of each metal halide lamp in which the composition of the contents does not satisfy conditions (2) and (4).
  • Samples 2 and 3 show cases of conventional metal halide lamps wherein experiments were conducted without charging bromine.
  • Sample 4 shows a case of a metal halide lamp in which bromine was charged together with iodine. In Sample 4, however, the relationship between numbers of moles does not satisfy the above conditions. It is apparent that in these Samples 2 and 4 the lumen maintenance factors become less than 70% after 48 hours, so that blackening of the tube wall occurs in an early period.
  • Fig. 3 is a graph showing service life data of Example 1 of the present invention and that of Sample 2. The excellence of the present invention can be clearly recognized from Fig. 3.
  • a ceramic sealed tube mainly a light-transmitting alumina (Al2O3) tube
  • quartz (SiO2) sealed tube because the mechanism of blackening of the alumina tube and preventing it is substantially similar to the one for the quartz tube.
  • a sealed tube which is made of a synthetic transparent glass material comprising quartz or alumina doped with a metal oxide, e.g., ZrO2 or TiO2.
  • the sealed tube need not to be completely transparent but one, e.g., made of frosted glass, that can partly transmit light therethrough may be used instead.
  • the inert gas in the sealed tube is not limited to argon gas, but other gases, e.g., helium, neon, krypton, xenon, or radon gas, can be used.
EP94301523A 1992-09-25 1994-03-02 Metallhalogenidlampe Expired - Lifetime EP0670588B1 (de)

Priority Applications (3)

Application Number Priority Date Filing Date Title
JP4256287A JPH06111769A (ja) 1992-09-25 1992-09-25 メタルハライドランプ
DE1994603190 DE69403190T2 (de) 1994-03-02 1994-03-02 Metallhalogenidlampe
EP94301523A EP0670588B1 (de) 1992-09-25 1994-03-02 Metallhalogenidlampe

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP4256287A JPH06111769A (ja) 1992-09-25 1992-09-25 メタルハライドランプ
EP94301523A EP0670588B1 (de) 1992-09-25 1994-03-02 Metallhalogenidlampe

Publications (2)

Publication Number Publication Date
EP0670588A1 true EP0670588A1 (de) 1995-09-06
EP0670588B1 EP0670588B1 (de) 1997-05-14

Family

ID=26136968

Family Applications (1)

Application Number Title Priority Date Filing Date
EP94301523A Expired - Lifetime EP0670588B1 (de) 1992-09-25 1994-03-02 Metallhalogenidlampe

Country Status (2)

Country Link
EP (1) EP0670588B1 (de)
JP (1) JPH06111769A (de)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5866981A (en) * 1995-08-11 1999-02-02 Matsushita Electric Works, Ltd. Electrodeless discharge lamp with rare earth metal halides and halogen cycle promoting substance
CN1118855C (zh) * 1997-04-03 2003-08-20 松下电器产业株式会社 金属卤化物灯
WO2009075943A2 (en) * 2007-12-06 2009-06-18 General Electric Company Metal halide lamp with halogen-promoted wall cleaning cycle
WO2013096067A1 (en) * 2011-12-19 2013-06-27 General Electric Company High intensity discharge lamp with improved startability and performance

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5532338A (en) * 1978-08-29 1980-03-07 Mitsubishi Electric Corp Metal halide lamp
EP0169510A2 (de) * 1984-07-24 1986-01-29 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Metallhalogenid-Hochdruckentladungslampe
DE3512757A1 (de) * 1985-04-10 1986-10-23 Philips Patentverwaltung Gmbh, 2000 Hamburg Metallhalogenid-hochdruckgasentladungslampe
EP0477668A1 (de) * 1990-09-24 1992-04-01 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Metallhalogenid-Hochdruckentladungslampe

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5532338A (en) * 1978-08-29 1980-03-07 Mitsubishi Electric Corp Metal halide lamp
EP0169510A2 (de) * 1984-07-24 1986-01-29 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Metallhalogenid-Hochdruckentladungslampe
DE3512757A1 (de) * 1985-04-10 1986-10-23 Philips Patentverwaltung Gmbh, 2000 Hamburg Metallhalogenid-hochdruckgasentladungslampe
EP0477668A1 (de) * 1990-09-24 1992-04-01 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Metallhalogenid-Hochdruckentladungslampe

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 4, no. 63 (E - 010) 13 May 1980 (1980-05-13) *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5866981A (en) * 1995-08-11 1999-02-02 Matsushita Electric Works, Ltd. Electrodeless discharge lamp with rare earth metal halides and halogen cycle promoting substance
DE19632220B4 (de) * 1995-08-11 2005-07-28 Matsushita Electric Works, Ltd., Kadoma Elektrodenlose Entladungslampe
CN1118855C (zh) * 1997-04-03 2003-08-20 松下电器产业株式会社 金属卤化物灯
WO2009075943A2 (en) * 2007-12-06 2009-06-18 General Electric Company Metal halide lamp with halogen-promoted wall cleaning cycle
WO2009075943A3 (en) * 2007-12-06 2009-08-27 General Electric Company Metal halide lamp with halogen-promoted wall cleaning cycle
WO2013096067A1 (en) * 2011-12-19 2013-06-27 General Electric Company High intensity discharge lamp with improved startability and performance
US8482198B1 (en) 2011-12-19 2013-07-09 General Electric Company High intensity discharge lamp with improved startability and performance

Also Published As

Publication number Publication date
EP0670588B1 (de) 1997-05-14
JPH06111769A (ja) 1994-04-22

Similar Documents

Publication Publication Date Title
US5451838A (en) Metal halide lamp
US6731068B2 (en) Ceramic metal halide lamp
EP1830388B1 (de) Quecksilber-Hochdruckentladungslampe deren Schwärzung durch geringen Gehalt an Lithium, Natrium und Kalium verringert wird
EP2229687B1 (de) Metallhalidlampe mit einer quelle aus verfügbarem sauerstoff
US5013968A (en) Reprographic metal halide lamps having long life and maintenance
EP0271911A2 (de) Lichtquelle mit seltene Erden-Halogenen mit verbesserter Rotemittierung
US20090146571A1 (en) Metal halide lamp with halogen-promoted wall cleaning cycle
US6921730B2 (en) Glass composition, protective-layer composition, binder composition, and lamp
EP1174905A1 (de) Leuchtstofflampe, Hochleistungsentladungslampe und Glühlampe mit erhöhter Lichtausbeute
US3530327A (en) Metal halide discharge lamps with rare-earth metal oxide used as electrode emission material
EP0670588B1 (de) Metallhalogenidlampe
US8482198B1 (en) High intensity discharge lamp with improved startability and performance
JP2003521804A (ja) 低圧水銀蒸発放電ランプ及びコンパクトな蛍光ランプ
US4229673A (en) Mercury metal-halide lamp including neodymium iodide, cesium and sodium iodide
EP0389907B1 (de) Beleuchtungseinrichtung
US3867664A (en) Electric discharge devices
JP3981301B2 (ja) メタルハライドランプ
EP1134776A2 (de) Hochdruckquecksilberdampfentladungslampe mit verminderter Empfindlichkeit gegenüber den Änderungen von Betriebsparametern
EP0634780B1 (de) Metall-Halogen Entladungslampe, optischer Beleuchtungsapparat und Bildvorführungssystem
US7276853B2 (en) Low-pressure mercury vapor discharge lamp
US5973454A (en) Short arc type metal halide lamp with encapsulated rare earth metal halides to increase color reproducibility
US20060082313A1 (en) Metal halide lamp
JP3269381B2 (ja) メタルハライドランプ
HU196861B (en) Low colour-temperature high-pressure metal-halide lamp with good colour reproduction
JP3378361B2 (ja) メタルハライドランプ、照明光学装置および画像表示装置

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

17P Request for examination filed

Effective date: 19950426

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB IT SE

17Q First examination report despatched

Effective date: 19951120

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB IT SE

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 FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRE;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.SCRIBED TIME-LIMIT

Effective date: 19970514

ET Fr: translation filed
REF Corresponds to:

Ref document number: 69403190

Country of ref document: DE

Date of ref document: 19970619

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Effective date: 19970814

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
REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20050224

Year of fee payment: 12

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20050308

Year of fee payment: 12

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20060301

Year of fee payment: 13

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: 20061003

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20061130

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20070302

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: 20060331

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: 20070302