To: atm{at}shore.net
From: Jim Burrows 
Reply-To: Jim Burrows 


At 16:29 2003-07-06 -0400, Scott Donaldson wrote:

>It might be the mirror with the "saw-tooth" figure....with
peaks and valleys
>of the teeth at the center of the zone.  Try more zones with alternating max
>over/under values?

Good suggestion!  Tried over/under with the 20 mm zone spacing and got .844
Strehl, slightly worse than the first try .857.  This is actually more
realistic, because the M-L "best-fit" (quotes intentional, not
the real optical best-fit) is the parabola with balanced transverse
aberrations, and over/under makes 200 mm f/6 the M-L "best-fit". 
To see if this would continue with more zones - nope, over/under with 10 mm
spacing gives .98 Strehl (the rapid back and forth makes the RMS smaller).

Hey, this is fun!  Tried over/under at Texereau's zones ... it gives .822. 
So if you figure to M-L tolerance, particularly with more zones, you're
working longer than necessary.  Another Wave-Optics lineman Strehl tackle
of the two Ray-Optics backs Misell and Lacroix .

         -- Jim Burrows
         -- mailto://burrjaw{at}earthlink.net
         -- http://home.earthlink.net/~burrjaw
         -- Seattle N47.4723 W122.3662 (WGS84)

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