Patent Treuhand Gesellschaft Fur Elektrische Gluhlampen Mbh

Patent-Treuhand-Gesellschaft F. Elektrische Gluehlampen Mbh

Patent-Treuhand-Gesellschaft F&uuml;r Elektrische Gl&uuml;hlampen Mbh

Dieter Meiss

Manfred Deisenhofer

Ekkehard Messner

Martin Zachau

Klaus Höhn

Matthias Schiplage

The invention relates to a fluorescent lamp for the illumination of plants, having a tubular discharge vessel, two electrodes which are fused in a gastight manner into the ends of the discharge vessel, a fill comprising at least a noble gas and mercury, and a phosphor coating on the inner wall of the vessel, the phosphor coating at least including a europium-doped barium magnesium aluminate phosphor of the BaMgAlO:Eu type and a cerium- and terbium-doped gadolinium zinc magnesium pentaborate phosphor of the Gd(Zn,Mg)BO:Ce,Mn type, and, to generate light with as high a light yield as possible and with a color temperature of between 4000 and 5500 K, the phosphor coating additionally includes an antimony- and manganese-doped calcium halophosphate phosphor of the Ca(PO)(F,Cl):Sb,Mn type. This novel phosphor coating allows the light yield to be increased by 10% if the proportion by weight of the individual phosphors is optimized.

Phosphor coating composition for a mercury low-pressure discharge lamp for illuminating plants

For improved ageing stability, an inorganic UV stabilizer, especially cerium aluminate, is added to the polymer so that the UV stability is improved.

Opto-electronic semiconductor component

A method for recycling thoriated tungsten objects such as thoriated tungsten scrap resulting from the fabrication of electrodes for lamps. The thoriated tungsten objects are oxidized, homogenized by mixing and chemically reduced under a hydrogen gas atmosphere to form thoriated tungsten. This method eliminates the need to separate the tungsten from its dopants. The thoriated tungsten obtained as the end product is returned to the production process and is preferably used as a raw material for the production of welding electrodes or thoriated tungsten discharge lamp electrodes.

Method for recycling objects consisting of thoriated tungsten

To inhibit, or at least sharply attenuate, fluorescence of a quartz-glass velope (10) surrounding a light source (11), such as a halogen incandescent lamp, a high-pressure discharge lamp, or the like, when the quartz glass is subjected to ultraviolet (UV) radiation from the light source, and has been doped with a UV radiation absorbing material, typically a cerium, or cerium-titanium doping, the quartz-glass envelope is additionally doped with barium and boron. The barium/boron in the doping is, preferably, present in quantities of between about 0.008 and 1.25%, by weight, with reference to the undoped quartz glass. Barium metaborate can be used, optionally together with praseodymium to attenuate the fluorescence. Preferably, barium and boron form a combined doping substance with cerium, in form of a cerium aluminate and metaborate, added to the starting material for the quartz glass, and before the quartz glass is fused from quartz sand or pulverized quartz crystal.

Fluorescence-suppressed quartz glass, and electric lamp with this quartz

To inhibit, or at least sharply attenuate, fluorescence of a quartz-glass velope (10) surrounding a light source (11), such as a halogen incandescent lamp, a high-pressure discharge lamp, or the like, when the quartz glass is subjected to ultraviolet (UV) radiation from the light source, and has been doped with a UV radiation absorbing material, typically a cerium, or cerium-titanium doping, the quartz-glass envelope is additionally doped with praseodymium or a praseodymium compound, such as praseodymium oxide or praseodymium aluminate. The pure praseodymium in the doping is, preferably, present in quantities of between about 0.008 and 1.25%, by weight, with reference to the undoped quartz glass. Barium metaborate can also be used, preferably together with praseodymium to attenuate the fluorescence. Preferably, the praseodymium is used as a combined doping with cerium, in form of a cerium-praseodymium aluminate, added to the starting material for the quartz glass, and before the quartz glass is fused from quartz sand or pulverized quartz crystal.

Growing community of inventors

Augsburg, Germany

Dieter Meiss