P3D Re: Viewer Light Bulb Question

[fj834@xxxxxxxxxxxxxxxxxxxxx (Dr. George A. Themelis)]

>is there any reason not to use a Xenon bulb (UV exposure maybe?).

I am not an expert, but I think that the gas mixture ("Halogen" vs.
"Xenon" vs. Nitrogen?) has very little to do with UV emission.  The
"glass" envelope does.  Halogen bulbs run at higher temperatures and
have quartz glass which is almost transparent to UV, hence the higher
UV emission from halogen bulbs.  I am not sure if the 2.5V halogen 
bulbs used in viewers actually have quartz glass.

>I've noticed a lot of Halogen usage and have found that there are a lot 
>of Xenon bulbs available for low voltage applications.

Actually, there is only one halogen 2.5V bulb with a screw E6 base, used
in these viewers.  I believe a Xenon bulb would be as good.  Not having
to worry about the base gives you more choices of light bulbs.

George Themelis


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