Koninklijke Philips Corporation N.v.

Adrianus Johannes Hendricus Petrus Van Der Pol

Ingrid Jozef Maria Snijkers-Hendrickx

Peter Arend Seinen

Leonie Maria Geerdinck

Simon Krijnen

Ronald Arjan Van Den Brakel

Roland Blasig

Engelbertus Cornelius Petrus Maria Vossen

Petrus Jacobus Maria Dohmen

Johannes Cornelis Antonius Van Ham

Low-pressure mercury vapor discharge lamp has an at least partly substantially cylindrical discharge vessel () with a length Ldv and with an internal diameter Din. The discharge vessel () encloses, in a gastight manner, a discharge space () provided with a inert gas mixture and with mercury. The discharge vessel () comprises discharge means (electrodes) for maintaining a discharge in the discharge space (). According to the invention, the ratio of the weight of mercury mHg in the discharge vessel () to the product of the internal diameterDin and the length of the discharge vessel Ldv is given by the relation: wherein C (0.01 (g/mm2. Preferably, 0.0005 (C(0.005(g/mm2. Preferably, the discharge vessel () contains less than 0.1 mg mercury. The discharge lamp according to the invention operates under unsaturated mercury conditions.

Low-pressure mercury vapor discharge lamp

Cd-free multicomponent glass to be used in particular as core glass ( ) in glass fibers for optical twisters and tapers, the glass being of the lanthanide flint type and comprising the following main constituents (in mol %):

Multicomponent glass, glass fiber, twister and taper

A low-pressure mercury-vapor discharge lamp is provided with a discharge vessel and a first and a second end portion ( ). The discharge vessel encloses a discharge space provided with a filling of mercury and an inert gas in a gastight manner. Each end portion ( ) supports an electrode ( ) arranged in the discharge space. An electrode shield ( ) encompasses the electrodes ( ) and, according to the invention, carries an electric current during operation, and is at a temperature &gE;250&deg; C., preferably &gE;450&deg; C., during nominal operation of the discharge lamp. Preferably, a first current supply conductor ( ) electrically contacts a first current divider ( ), which is electrically connected to a second current divider ( &prime;) via a shell-shaped body ( ). Said second current divider ( &prime;) electrically contacts the electrode ( ), which is connected to the second current supply conductor ( &prime;), the electrode shield ( ) is made from stainless steel, in particular a chromium nickel steel. Preferably, the heat dissipation of the electrode shield ( ) during nominal operation ranges between 0.1 and 10 Watts. Preferably, the electrode shield ( ) is made from a ceramic material or carbon. The discharge lamp exhibits a comparatively low mercury consumption.

Low-pressure mercury-vapor discharge lamp having electrode shield carrying direct electric current

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Eindhoven, Netherlands

Adrianus Johannes Hendricus Petrus Van Der Pol