Re: [ATM] Luri-Houghton prescriptions.

["Richard F.L.R. Snashall" <rflrs@rcn.com>]

Ukyo Chen wrote:

> If the mirror has the same radius with the first corrector surface, 
> you still need to deal with 4 different radius. For 'Infinity', you 
> still need to make a plane, that is not easy.
>
Actually, it is a plane +/- the curvature tolerance; just like any
other surface.

> Either choose the best result, use 5 different radius;
> Or choose the most simple way, use equal radius.

Given the problems we've been having getting glass of sufficient
diameter and thickness, the best result may not be as good an option
any more.  Makeing the last surface flat is a compromise to overcome
our other problems.
_______________________________________________
ATM mailing list http://www.atmlist.net/