High pressure discharge lamp with vessel having a UV radiation absorbing portion of quartz glass
AssigneeU.S. Philips Corporation
InventorsCharles C. E. Meulemans, Gerardus H. A. M. van der Steen, Jan van Werkhoven
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Abstract
High-pressure discharge lamp according to the invention have a quartz glass lamp vessel (1) which consists locally of UV-absorbing quartz glass (shaded region 2). During operation of the lamps the normally colder wall parts of the lamp vessel in this region thus assume a higher temperature, as a result of which the efficiency of the lamp is increased while said regions (2) nevertheless remain transparent to visible radiation.
Claims5
A high-pressure discharge lamp having a tubular, vacuum-tight sealed quartz glass lamp vessel, a pair of electrodes disposed in said vessel, current supply conductors extending through the wall of said vessel to said pair of electrodes, said lamp vessel having an ionizable gas filling and means to locally increase the temperature of one or more regions of the lamp vessel during operation, said lamp vessel having at least one region which consists solely of ultraviolet radiation-absorbing quartz glass, which is transparent to visible radiation, the remainder of said vessel being composed of a different quartz material which is ultraviolet radiation transmitting.
Dependencies are inferred from the claim text.