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US 6,674,240 B1Granted
Gas discharge lamp comprising an oxide emitter electrode
AssigneeKoninklijke Philips Electronics N.V.
InventorsGeorg Gärtner, Wilem Jacobus Van Den Hoek
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AssigneeKoninklijke Philips Electronics N.V.
InventorsGeorg Gärtner, Wilem Jacobus Van Den Hoek
Estimating the term…
A gas discharge lamp, in particular a low-pressure gas discharge lamp, comprising an electrode including a carrier of an electrode metal and a first electrode coating of an electron-emitting material, which material comprises a metal powder preparation of a powder of a reducing metal selected from the group formed by aluminum, silicon, titanium, zirconium, hafnium, tantalum, molybdenum, tungsten and the alloys thereof, which metal powder preparation is provided with a powder coating containing a noble metal selected from the group formed by rhenium, cobalt, nickel, ruthenium, palladium, rhodium, iridium and platinum, and the alloys thereof, and said material comprising at least one alkaline earth metal oxide selected from the group formed by calcium oxide, strontium oxide and barium oxide, is characterized by a uniform emission current and a long service life.
A gas discharge lamp comprising an electrode including a carrier of an electrode metal and a first electrode coating of an electron-emitting material, which material comprises a metal powder preparation of a powder of a reducing metal of a tungsten-iridium alloy, which metal powder preparation is provided with a powder coating of iridium, said material comprising at least one alkaline earth metal oxide selected form the group consisting of calcium oxide, strontium oxide and barium oxide.
A gas discharge lamp comprising an electrode including a carrier of an electrode metal and a first electrode coating of an electron-emitting material, which material comprises a metal powder preparation of a powder of a reducing metal selected from the group consisting of aluminum, silicon, titanium, zirconium, hafnium, tantalum, molybdenum, tungsten and the alloys thereof, which metal powder preparation is provided with a powder coating containing a noble metal selected from the group consisting of rhenium, cobalt, nickel, ruthenium, palladium, rhodium, iridium and platinum, and the alloys thereof and wherein said reducing metal further comprises zirconium oxide, and said material comprising at least one alkaline earth metal oxide selected from the group consisting of calcium oxide, strontium oxide and barium oxide.
Dependencies are inferred from the claim text.