Re: [ATM] How fast is 150mm f/3.3 lensless Schmidt?

["Bob May" <rmay@nethere.com>]

Ya look at the application and you'll find that it really didn't
matter how bad the optics were for such things.  All they had to
do was focus the spot on the tube which probably hjad a spot size
of about 0.005" and transfer that to the screen with about a
magnification of 4or 5 to do a decent job.  Not exactly
diffraction limited optics there!
Remember that the Schmidt corrector is a neat way to convert a
sphereical mirror into a parabolic mirror effectively.  The
display tube probably also was curved to match the focal points
needed for a proper focus to all parts of the flat scree in
addition.
Bob May

rmay at nethere.com
http: slash /nav.to slash bobmay
http: slash /bobmay dot astronomy.net


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