Re: Ultraviolet "Barlow" lens?

Thanks for the tip. I found the Opto Sigma UV achromats. The ones that have large enough aperture are $2000 each but the show stopper is that none have negative focal lengths. A further search for other manufactures hasn't produced useful results.

Bret Cannon wrote:
Opto Sigma has a line of UV achromats that you might look at. I don't know how they would do for you application, but they are CaF2/fused silica doublets as I recall.
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