From: "Jerald F. Wright" 
To: Tom Krajci 
CC: atm{at}shore.net
Reply-To: "Jerald F. Wright" 




Tom Krajci wrote:

>
> As your optics get faster, the wire test has more strong points in its
> favor.  Also, compared to the Gavoila/caustic test...the wire test only
> needs to measure longitudinal motion...so you can use the same traveling
> stage as you do for the Foucalt test, instead of making a more complex
> two-axis stage for caustic testing.
>

    For someone making their first mirror  some of the well designed but
easy to make testers will be fine.  But after the first one, for someone
who will be making more than a few mirrors it would be wise for them to
take the time to build a super fine tester.  Part of doing this would be to
go ahead and put the more complex two axis movement on it even if you don't
think you need it. It is nice to have a tester that you can easily attach
whatever you want for whatever test you desire. If nothing else slits,
wires, knives, and gratings stay parallel with lateral motion. Its worth
the trouble.

Jerry

--- BBBS/NT v4.00 MP