High-pressure discharge lamp having a ceramic discharge vessel

US8018156B2 · kind B2 · utility

Assignee

• OSRAM GmbH · DE

Inventors

• Wolfram Graser · Munich, DE
• Dieter Trypke · Falkensee, DE

Key dates

• Filing date: Feb 14, 2007
• Grant date: Sep 13, 2011
• Expiry date: Feb 13, 2028

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01J61/36
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

High-pressure discharge lamp having a ceramic discharge vessel, in which two electrodes and a light-emitting filling are contained, wherein capillaries are positioned at the ends of the discharge vessel, in which capillaries leadthroughs are sealed off, which leadthroughs are each connected to an electrode (15) consisting of tungsten. The electrode (15) is in the form of a pin and integrally comprises two parts (25, 26) having different diameters, wherein the first part (25) having a given diameter D1 forms the electrode tip, the second part (26) having a diameter D2 is positioned in the capillary, and the diameter D2 of the second part makes up at least 108% of the diameter D1 of the first part. The total length L of the electrode (15) is split between the first part (25) with a partial length L1 and the second part (26) with a partial length L2 such that L2 makes up approximately 30 to 70% of the total length L, wherein the beginning of the maximum diameter D2 coincides with the beginning of the capillary or deviates therefrom by a maximum of 10% of the length L.