Low-pressure mercury vapor discharge lamp with improved auxiliary amalgam

• Main Authors: VAN DEN BOGERT WILLEM JOHANNES, OOMS PIETER CORNELIS, STEL HINDRIK HERMANNUS, DE PUTTER CORNELIS, VAN HAASTRECHT JOHANNES THEODORUS JACOBUS, WITS JEROEN JAN, VAN DEN BRAKEL RONALD ARJAN
• Format: Patent
• Language: English
• Published: 16.03.2004
• Edition: 7
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS; ELECTRICITY

A low-pressure mercury vapor discharge lamp is provided with a discharge vessel (10). The discharge vessel comprises tubular end portions (11; 11'), which each have a longitudinal axis (12; 12'). The discharge vessel (10) encloses a discharge space (18) containing a filling of mercury and an inert gas in a gastight manner. Electrodes (20; 20') are arranged in the discharge space (18). An auxiliary amalgam is provided on a carrier (25; 25') in the proximity of the electrodes (20; 20'). According to the invention, a part of the carrier (25; 25') is arranged in a plane transverse to the longitudinal axis (12; 12'). Preferably, a stem (21; 21') in the tubular end portion (11; 11') carries, apart from the electrode (20; 20'), a support in the form of a wire (23; 23') or an extended exhaust tube, which support carries the carrier (25; 25'). In an alternative embodiment, the carrier is clamped directly onto the stem. Preferably, the carrier (25; 25') is electrically insulated with respect to the electrode. Preferably, a distance d between the carrier (25; 25') and the electrode (20; 20') lies in the range 1<=d<=3 mm. According to the invention, the discharge lamp has a relatively short run-up time.