Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
  • H01J61/00—Gas-discharge or vapour-discharge lamps
  • H01J61/02—Details
  • H01J61/12—Selection of substances for gas fillings; Specified operating pressure or temperature
  • H01J61/18—Selection of substances for gas fillings; Specified operating pressure or temperature having a metallic vapour as the principal constituent
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
  • H01J61/00—Gas-discharge or vapour-discharge lamps
  • H01J61/02—Details
  • H01J61/12—Selection of substances for gas fillings; Specified operating pressure or temperature
  • H01J61/18—Selection of substances for gas fillings; Specified operating pressure or temperature having a metallic vapour as the principal constituent
  • H01J61/22—Selection of substances for gas fillings; Specified operating pressure or temperature having a metallic vapour as the principal constituent vapour of an alkali metal

Definitions

• the metal halogenides introduced into high-pressure mercury-vapor lamps are generally iodides and the metal halogenide which is added in the present invention is cesium iodide, cesium having a low ionization 1.
• Field of the Invention 5 energy.
• the present invention relates to improvements in high-pressure mercury-vapor electric discharge lamps and, more particularly, to lamps of this type which contain, in addition to mercury, alkali metal halogenides. DESCRIPEFERRED 2.
• Table 1 shows three examples A, B and rays, as in the case of metals such as thallium, sodium C of fillings for high-pressure mercury-vapor lamps and indium, or by very numerous rays spread over the having a power of 400 watts obtained with an inner entire spectrum as in the case of rare-earth elements or tube having a diameter of 18 mm and a spacing betransition metals such as scandium, hafnium, thorium. tween electrodes of 50 mm.
• the left- The lamp is generally formed of an outer glass envelope side column shows the possible pressure and weight and an inner high pressure discharge tube of vitreous limits in torrs (millimeters of mercury) and in millimaterial Such as q grams, respectively, of the filling materials and the The metals are usually introduced into the lamp in 20 right-side column the values used in an embodiment.
• the form of halogenides more p r icul rly, in the The left hand column lists the various materials in the form of iodides which are highly volatile halogenides. compositions.
• One of the most used iodides is sodium iodide which, I he exam leA relates to addition of yttrium and cedue to its low vapor pressure at the lamp operation sium iodide with mercury iodide in a high-pressure temperature, is gaseous within the discharge region of mercury-vapor lamp already containing iodides of sothe inner tube and liquid about the tube walls. Due to dium (having a characteristic yellow color), of thallium a diffusion phenomenon through the tube walls, the So- (having a green color) and of indium (having a blue dium iodide is decomposed and the sodium leaves the color).
• the example B relates to addition of yttrium and cethe tube, which restrains the electric discharge phei m iodide with mercury iodide in a high-pressure nomenon causing an increased voltage across electrode mercury-vapor lamp already containing sodium Iodid terminals after a few hundreds of Operation h r and scandium, which have a very close color spectrum. renders lighting difficult.
• One of the solutions adopted to slow the sodium diftri m is replaced by thorium and magnesium. fusion is in locating the inner tube within an area of an Yttrium may also be replaced by hafnium, aluminum outer envelope filled with a neutral gas such as nitroand rare earth metals within limits from 0.1 mg to 5 mg. gen, at adequate pressure. Thus lamps are obtained in Although the addition of only one metal is sufficient which the electrode terminal voltage increases less rapit is clear that addition of several metals of the above y with timementioned list may also be convenient.
• an object of the present invention to D E R E E Materials Range x. ange x. provide an improved hlghpressure mercury vapor Argon mm 40mm 20 low 40 mm 20 electric discharge lamp containing an alkali-metal halo- Sodium iodide 25 100 mg 50 40 w 80 mg gcnidc, by including additional materials to maintain 6O Thqlliuflfl iqdide 2 I05 s 3 thc o eratin v )lt' s b't' t' ll t t 'th t' lndmm md'de mg 03 p g u 5 y cons an wl Cesium iodide 0.5 to 10 mg 5 0.5 to 10 mg 5 In such lamps the alkali-metal halogenides, in particmercury iodide 5 to l0 mg g 5 to 20 mg lg ercury l8 l8 ular, may be sodiumha
• Table 2 shows two examples of fillings for highpressure mercury-vapor lamps designed to provide a power of 1,000 watts, the burner diameter being 22
• Table 3 shows two examples of fillings for highpressure mercury-vapor lamps designed for providing a power of 2,000 watts, the burner diameter being 30 mm and the spacing between electrodes of 145 mm.
• the high-pressure mercuryvapor lamps manufactured according to the present invention have an operating voltage which is increased by less than two volts per thousand operation hours, which constitutes a substantial improvement with respect to prior art lamps of which the operation voltage was increasing by eight to fifteen volts per thousand operation hours.
• a high-pressure mercury-vapor lamp filling comprising a mixture of materials including mercury, sodium iodide, argon, mercury iodide, cesium iodide, yttrium and a further material selected from the group consisting of thallium iodide, indium iodide, scandium, thorium and magnesium.
• the lamp of claim 1 including an additional further material selected from the group consisting of thallium iodide, indium iodide, scandium, thorium and magnesium.

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• Discharge Lamp (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=9060615

Family Applications (1)

Country Status (6)

Cited By (9)

Families Citing this family (5)

Citations (5)

• 1970
  • 1970-08-27 FR FR7031287A patent/FR2102866A5/fr not_active Expired
• 1971
  • 1971-08-04 DE DE19712139078 patent/DE2139078A1/de not_active Withdrawn
  • 1971-08-20 GB GB3915171A patent/GB1327343A/en not_active Expired
  • 1971-08-24 US US00174535A patent/US3740605A/en not_active Expired - Lifetime
  • 1971-08-25 NL NL7111659A patent/NL7111659A/xx not_active Application Discontinuation
  • 1971-08-27 BE BE771836A patent/BE771836A/xx unknown

Patent Citations (5)

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