|Publication number||US3654506 A|
|Publication date||Apr 4, 1972|
|Filing date||Jul 27, 1970|
|Priority date||Aug 8, 1969|
|Also published as||DE1940539A1, DE1940539B2, DE1940539C3|
|Publication number||US 3654506 A, US 3654506A, US-A-3654506, US3654506 A, US3654506A|
|Inventors||Dobrusskin Alexander, Kuhl Bernard|
|Original Assignee||Patra Patent Treuhand|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (5), Referenced by (36), Classifications (8)|
|External Links: USPTO, USPTO Assignment, Espacenet|
United States Patent Kiihl et al.
Dobrusskin, Tauikirchen, both of Germany latent-Treuhand-Gesellschaft, fur elektrische Glul'ilampen mbll, Munich, Germany  Filed: July 27,1970
 Appl.No.: 58,292
 Foreign Application Priority Data Aug. 8, 1969 Germany ..P 19 40 539.1
 US. Cl ..313/184, 313/225, 313/229  Int. Cl. ..H01j 61/12  Field of Search ..313/229,184, 225
[451 Apr. 4, 1972 Primary Examiner-Roy Lake Assistant Examiner-Palmer C. Demeo Attorney-Flynn and F rishauf 7] ABSTRACT High pressure mercury vapor discharge lamp without outer jacket and with a wall loading of between and 100 W/cm preferably -60 W/cm and a medium arc length corresponding to a load per cm of arc length of between and 1000 W/cm, preferably -850 W/cm. Additives of thallium halide and halides of rare-earth metals, preferably of thulium and holmium, in a ratio of weight of halogen to metal between 2 and 10. Color temperature is 6,000 K, index of color rendition 92.
6 Claims, 1 Drawing Figure Patented A ril 4, 1972 3,654,506
Dr. Bernhard KUhl Alexander Dobrusskin WVEHIOP;
W W BY ATTORNE I HIGH PRESSURE MERCURY VAPOR DISCHARGE LAMP WIT I'I METAL HALIDE ADDITIVE The invention relates to a high pressure mercury vapor discharge lamp with metal halide additive, the discharge vessel being preferably of ellipsoidal shape, and made of heat-resisting, light-transmissive material. I
Two different types of high pressure discharge lamps with metal halide filling are generally known:
1. The type of lamp which is chiefly used for general lighting purposes such as, for instance, street lighting (see for example, German Patent specification No. 1,184,008) is a development of the high pressure mercury vapor discharge lamps. It comprises a tubular discharge vessel of quartz glass with one leadin wire each sealed or pinch-sealed into each end. The spacing of the electrodes is approximately 50 mm. The wall loading of such lamps is about 10 W/cm. The vessel is filled, besides mercury and a starting gas, mostly with the halides, preferably the iodides, of sodium and thallium; rare-earth metals like dysprosium, holmium, erbium or thulium (see US. Pat. No. 3,536,947; US. Pat. No. 3,452,238) are used. The discharge vessel, the so-called arc tube, is enclosed in a single-ended outer envelope, which is exhausted or filled with gas in order to reduce heat losses. The lamps have a luminous efficiency of over 50 lm/W, and mostly below 801m/W; and a life of several 1,000 hours.
2. The lamps of the other type are used for projection purposes and in signaling and they are, with regard to their field of application, a further development of the high pressure xenon discharge lamps used for these purposes. They provide high luminance and have, therefore, short arcs. The lamps are operated with extremely high wall loading of far more than 100 W/cm for instance with 400 to 1,000 W/cm The wall thickness of the discharge vessel is from 3 to 5 mm; the spacing of the electrodes is in most cases less than mm. The lamps are so-called one-component lamps and contain, besides a basic gas as the filling excitable to luminance, the halides, for instance, of indium or gallium or aluminum; in addition, mercury is often used as a buffer gas but not as an element to be excited. An outer envelope is not necessary with these lamps (see U.S. Pat. No. 3,259,777, Dutch published Patent application 67 10 944). A projection lamp which contains scandium halide as the excitable element (see German Patent 1,177,248) is also known. The luminous efficiency of these one-component lamps is more than 90 lm/W, the useful life is several 100 hours.
It an object of the invention to provide a lamp which represents a further development of lamps of the first-mentioned type, and which at the same time, shows characteristics of the second type, for instance, with regard to luminous efficiency. Another object is the optimum dimensioning of such a lamp.
SUBJECT MATTER OF THE INVENTION:
The lamp is a high pressure mercury vapor discharge lamp with metal halide additive; it has a single wall, preferably ellipsoidal discharge vessel of heat-resisting, light-transmissive material. According to the invention, the lamp has a wall loading of between 10 and 100 W/cm, preferably 20-60 W/cm with a load per cm of arc length between 100 and 1,000 W/cm, preferably from 150 to 850 W/cm; and the additive is composed of halides of rare-earth metals, preferably of thulium and/or holmium, and/or halide of thallium, and wherein the ratio of weight of halogen to metal is between 2 and 10. No outer envelope is used.
The invention will be described by way of example with reference to the accompanying drawing wherein the single figure is a schematic longitudinal view of the lamp.
The luminous efiiciency of lamps increases with the specific loading in Watt per centimeter of arc length. With the same power input and a reduction of the electrode spacing an increase in luminous efficiency is then to be expected. Surprisingly, however, the luminous efficiency obtainable with lamps of medium electrode spacing, according to the invention, is much greater than could be expected from theoretical considerations and amounts to to 130 lm/W depending on the respective power input of the lamp, without, however, approaching the wall loading of the second type of lamp. A greater power input with lamp dimensions maintained constant implies, however, that the wall loading of the lamp rises and hence lamp life decreases. Unexpectedly, however, it has been found that compared with the above described shortare lampsa halogen cycle starts already with low wall loadings of the lamps according to the invention. This is in contrast to the known high pressure mercury vapor discharge lamps with metal halide additives in which the halogen cycle is hardly still effective. The invention shows that by choosing the specific load per cm of arc length and wall loading, it is possible to obtain a maximum of luminous efficiency far beyond that which would be expected from a mere change of dimensions. In order to obtain the halogen cycle an excess of halogen must be present in the lamp; yet, this excess must be chosen so low that the luminous efficiency is not impaired. From the high wall loading, it is obvious that the heat-accumulating outer envelope has to be omitted. This facilitates at the same time lamp manufacture and renders it less expensive. Besides, providing the lamp with bases at both ends allows the application of higher starting voltage and enables restarting of the lamp when still hot.
As an addition to mercury, halogen compounds, preferably the iodides of thulium or holmium in a quantity of from 0.25 to 11 mg/cm, preferably from 0.5 to 4 mg/cm when filled into the discharge vessel are advantageous. An excess of iodine of up to 50 percent of the quantity of iodine equivalent to the rare-earth metals is necessary to ensure the halogencycle process and thus long lamp life. When using a thulium iodide additive, a high color rendition index of about 92 is obtained with a color temperature of 6,000 K which renders the lamp particularly suitable for color television and color photography.
The discharge tube 1 is of quartz glass which contains only little hydrogen and can be coated inside with a protective layer 2, preferably of boron oxide. The maximum inner diameter of the discharge vessel is 15 mm, the volume 2.3 cm Each end of the discharge vessel is provided with a rod-shaped nonactivated tungsten electrode 3, 4, having a diameter of 0.9 mm. Electrode spacing is 12 mm. The ends of the discharge vessel are provided with a reflecting coating 5. The bases 6 and 7 are connected to a voltage source; operating voltage is approximately 80 V, current approximately 7.5 amps.
The filling of the discharge vessel 1 consists of a basic gas as starting aid, for instance, argon at a pressure of 50 torr; and 1.5 mg of thulium, 4 mg of mercury and 7 mg of HgJ the ratio of weight of iodine to thulium being 2.3. The mercury iodide reacts in the discharge vessel with thulium according to the formula The structural datas and the fill quantities are applicable to a lamp of 500 W power input. The luminous flux is 45 klm, the luminous efficiency 901m/W, the color temperature 6,000 K, the chromaticity coordinates x/y 0.32/0.32, the color rendition index 92. Lamps having a power input of 600 W, had a luminous efficiency of lm/W. Lamps having a power input of 5 kW had a luminous efficiency of lm/W.
1. High pressure mercury vapor discharge lamp comprising a single, unenclosed envelope of heat-resisting light-transmissive material forming a discharge vessel;
a fill of rare gas forming a starting gas in said vessel;
said vessel, when the lamp is operating, having a wall loading of between 10 and 100 W/cm and a loading per cm of arc length of between 100 and 1,000 W/cm;
the discharge vessel further containing from 0.25 to 11 mg/cm of a halide of the rare-earth metals,
from 0 to 0.2 mg/cm of thallium halide,
from 2 to 10 mg/cm of mercury,
the load per cm of 5 earth metal comprises a halide of thulium or holmium.
5. Lamp according to claim 1 wherein the additive is thallium iodide.
6. Lamp according to claim I, wherein the lamp envelope is ellipsoidal in shape.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US3234421 *||Jan 23, 1961||Feb 8, 1966||Gen Electric||Metallic halide electric discharge lamps|
|US3259777 *||May 9, 1961||Jul 5, 1966||Gen Electric||Metal halide vapor discharge lamp with near molten tip electrodes|
|US3334261 *||Oct 24, 1965||Aug 1, 1967||Sylvania Electric Prod||High pressure discharge device having a fill including iodine mercury and at least one rare earth metal|
|US3452238 *||Dec 5, 1966||Jun 24, 1969||Westinghouse Electric Corp||Metal vapor discharge lamp|
|US3536947 *||Mar 20, 1968||Oct 27, 1970||Tokyo Shibaura Electric Co||High pressure discharge lamps|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US3771009 *||Dec 27, 1971||Nov 6, 1973||Gte Laboratories Inc||Electrode discharge device with electrode-activating fill|
|US4020377 *||Apr 8, 1976||Apr 26, 1977||Patent-Treuhand-Gesellschaft Fur Elektrische Gluhlampen Mbh||High pressure mercury vapor discharge lamp|
|US4134039 *||Apr 6, 1977||Jan 9, 1979||Egyesult Izzolampa Es Villamossagi Reszvenytarsasag||High-pressure gas discharge light source|
|US4161672 *||Jun 5, 1978||Jul 17, 1979||General Electric Company||High pressure metal vapor discharge lamps of improved efficacy|
|US4298813 *||Oct 23, 1978||Nov 3, 1981||General Electric Company||High intensity discharge lamps with uniform color|
|US4647814 *||Jul 15, 1985||Mar 3, 1987||Patent-Treuhand Gesellschaft Fur Elektrische Gluhlampen Mbh||High-power, high-pressure metal halide discharge lamp with improved spectral light distribution|
|US4686419 *||Feb 13, 1986||Aug 11, 1987||Patent Treuhand Gesellschaft Fur Elektrische Gluhlampen Mbh||Compact high-pressure discharge lamp with a fill including cadmium and lithium halide|
|US4801846 *||Oct 23, 1987||Jan 31, 1989||Gte Laboratories Incorporated||Rare earth halide light source with enhanced red emission|
|US5138227 *||Mar 28, 1990||Aug 11, 1992||Patent Treuhand Gesellschaft Fur Elektrische Gluhlampen M.B.H.||High-pressure discharge lamp, particularly double-ended high-power, high-wall loading discharge lamp, and method of making the same|
|US5144201 *||Feb 23, 1990||Sep 1, 1992||Welch Allyn, Inc.||Low watt metal halide lamp|
|US5220244 *||Nov 27, 1991||Jun 15, 1993||Iwasaki Electric Co. Ltd.||Metal halide discharge lamp|
|US5264760 *||Jul 18, 1991||Nov 23, 1993||Patent-Treuhand-Gesellschaft Fur Elektrische Gluehlampen Mbh||High-pressure metal halide discharge lamp with a fill containing nickel halide|
|US5416383 *||May 11, 1994||May 16, 1995||Patent-Treuhand Gesellschaft Fuer Elektrische Gleuhlampen Mbh||High-pressure discharge lamp and low-noise lamp operating system|
|US5708328 *||Jun 3, 1992||Jan 13, 1998||General Electric Company||Universal burn metal halide lamp|
|US5965984 *||Oct 18, 1996||Oct 12, 1999||Matsushita Electric Industrial Co., Ltd.||Indium halide and rare earth metal halide lamp|
|US6005356 *||Oct 20, 1997||Dec 21, 1999||Matsushita Electric Industrial Co., Ltd.||Operating method and operating apparatus for a high pressure discharge lamp|
|US6107742 *||Apr 1, 1998||Aug 22, 2000||Matsushita Electronics Corporation||Metal halide lamp|
|US6225754||Apr 19, 1999||May 1, 2001||Matsushita Electric Industrial Co., Ltd.||Operating method and operating apparatus for a high pressure discharge lamp|
|US6545413 *||Oct 9, 1998||Apr 8, 2003||Matsushita Electric Industrial Co., Ltd.||Metal halide lamp|
|US7486026 *||Nov 9, 2006||Feb 3, 2009||General Electric Company||Discharge lamp with high color temperature|
|US7973482||Apr 14, 2005||Jul 5, 2011||OSRAM Gesellschaft mit beschraenkler Haftung||High-pressure discharge lamp with halogens|
|US8449343 *||Jan 13, 2010||May 28, 2013||Seiko Epson Corporation||Discharge lamp having a heat resistant film and method for producing same|
|US9171712||Jul 5, 2014||Oct 27, 2015||National Institute Of Standards And Technology||Lamp having a secondary halide that improves luminous efficiency|
|US20070200504 *||Apr 14, 2005||Aug 30, 2007||Patent-Treuhand-Gesellschaft Fur Elektrische Gluhl||High-Pressure Discharge Lamp|
|US20080111489 *||Nov 9, 2006||May 15, 2008||Johnston Colin W||Discharge lamp with high color temperature|
|US20100213840 *||Jan 13, 2010||Aug 26, 2010||Seiko Epson Corporation||Discharge lamp and method for producing same, light source device, and projector|
|CN1106671C *||Jan 11, 1997||Apr 23, 2003||奥斯兰姆施尔凡尼亚公司||金属卤化物灯|
|DE3110465A1 *||Mar 18, 1981||Jan 28, 1982||Ilc Technology Inc||Hoch-intensitaets-lampe mit vorgefertigten elektrodenbauteilen|
|EP0128550A1 *||Jun 8, 1984||Dec 19, 1984||GTE Products Corporation||single-ended metal halide discharge lamp with minimal color separation and method of fabrication|
|EP0134426A1 *||Jun 8, 1984||Mar 20, 1985||GTE Products Corporation||Single-ended metal halide discharge lamp with minimal colour separation|
|EP0169510A2 *||Jul 19, 1985||Jan 29, 1986||Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH||Metal halide high-pressure discharge lamp|
|EP0391283A2 *||Mar 30, 1990||Oct 10, 1990||Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH||Double-based high-pressure discharge lamp|
|EP0400980A2 *||May 30, 1990||Dec 5, 1990||Iwasaki Electric Co., Ltd.||Metal halide lamp|
|EP0784334A1 *||Dec 18, 1996||Jul 16, 1997||Osram Sylvania Inc.||Metal halide lamp|
|WO2005101455A2 *||Apr 14, 2005||Oct 27, 2005||Patent-Treuhand- Gesellschaft Für Elektrische Glühlampen Mbh||High-pressure discharge lamp|
|WO2005101455A3 *||Apr 14, 2005||Aug 24, 2006||Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh||High-pressure discharge lamp|
|International Classification||H01J61/82, H01J61/00, H01J61/12|
|Cooperative Classification||H01J61/125, H01J61/827|
|European Classification||H01J61/12B, H01J61/82C|