[ATM] ATM Digest, Vol 33, Issue 15

[Bob May]

Actually, you will have an offaxis part of the figure of
revolution.  Put it at the same distance from the center of the
telescope so that the 3 mirrors are placed at the correct
distance from the center of the original mirror and they will be
doing their part as a hyperbola.  Basically an expensive way to
do the job!
Yes, it is possible to phase the 3 mirrors and locate them well
enough that their Airy discs overlap but, as the MMT has shown,
this isn't a trivial task.
Bob May
bobmay at nethere.com
http: slash /nav.to slash bobmay
http: slash /bobmay dot astronomy.net
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