Thoriated Lenses

[Ronald Morgan <rgmorgan@lanl.gov>]

Hi Folks,
I've noticed that most of the better camera lenses I've seen lately are
loaded with thorium.  Can anyone tell me why?  It occurs to me that the
thorium would increase the density and (surely?) the refractive index, but
I don't know enough about optics to know why that would be an advantage.
The only thing else that I could think of is that the thorium might boost
the temperatures in the casting process...again, why might that be an
advantage?
Thanks,
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       Ron Morgan <rgmorgan@lanl.gov>
       Operational Health Physics (ESH-1)
       Los Alamos National Laboratory
       MS E-503, Los Alamos New Mexico, 87545 (USA)
       Phone (505) 665-7843
       Fax   (505) 667-1009
       Voice pager 104-1787

	 mailto:rgmorgan@lanl.gov

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