Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!uunet!microsoft!gordonl
From: gordonl@microsoft.UUCP (Gordon LETWIN)
Newsgroups: sci.electronics
Subject: Re: Halogen news
Summary: IR reflective coating
Message-ID: <60080@microsoft.UUCP>
Date: 27 Dec 90 19:00:22 GMT
References: <4676@mcgp1.UUCP> <3035@naucse.cse.nau.edu> <1348@inews.intel.com> <39089@nigel.ee.udel.edu>
Organization: Microsoft Corp., Redmond WA
Lines: 13


Some folks have posted that they'd wondered why halogen bulbs weren't
coated with IR reflectors to improve efficiency before now.  The problem
was finding a coating which could take the heat (and of course which was
also transparent to visable light).  Natually, the technique only works
on bulbs with the proper shape, but most halogen bulbs are cylinderical.
The article that I saw showed a guy holding the bulb itself - a bit larger
than a peanut - in one hand, and an ordinary looking PAR reflector "bulb"
in the other.  Presumably the halogen bulb mounts inside the PAR thing 
(those cone-shaped bulbs you see in outdoor fixtures) for this application.
The blurb didn't say.

	gordon letwin