Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!tut.cis.ohio-state.edu!ucbvax!pasteur!cory.Berkeley.EDU!charless From: charless@cory.Berkeley.EDU (Charles R. Sullivan) Newsgroups: sci.electronics Subject: Re: Halogen news (Re: Do Halogen lamps need ballasts?) Message-ID: <10040@pasteur.Berkeley.EDU> Date: 6 Jan 91 21:42:23 GMT References: <16120020@col.hp.com> Sender: news@pasteur.Berkeley.EDU Reply-To: charless@cory.Berkeley.EDU Lines: 16 In article <16120020@col.hp.com> dunphy@col.hp.com (Dan Dunphy) writes: >>/ col:sci.electronics / schuster@cup.portal.com (Michael Alan Schuster) / 4:41 pm Nov 29, 1990 / >> >>What's the principle behind the "krypton" flashlight bulbs being sold >>now, and market as "70% brighter" than the standard type? >>---------- >I suspect they use a principle similar to halogen. I just >tried my first. They are a lot brighter. I don't know if Krypton bulbs use a halogen cycle too, but the idea of the krypton is that it is a heavier gas than the usual fill gas, and so retards the evaporation of tungsten more, and I think has lower thermal conductivity. You can take the benifits of this as longer life or higher efficiency, depending on what temperature you design the filament to operate at. Charlie Sullivan charless@cory.berkeley.edu