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Re: [ATM] Reverse engineering a lens.

To: "Thomas Janstrom" <atm@atmlist.net>
Subject: Re: [ATM] Reverse engineering a lens.
From: Richard <cnc@cncservo.co.uk>
Date: Sun, 11 Sep 2005 15:16:36 +0100
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Reply-To: Richard <cnc@cncservo.co.uk>
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Hi Thomas,

Sunday, September 11, 2005, 12:50:33 PM, you wrote:

TJ> Lens One.

Agree with Richard, as a symmetric biconvex, the edge thickness
would have to be 0.445mm to make sense.

R1      R2       te
558.67  -558.67  0.445
522.69  -600.00  0.445
429.37  -800.00  0.438
338.90  -1600.0  0.413

The only way I can make the edge and centre thickness tie in
with the focal length is with glass type similar to N-SF56 and
R1=-R2=853mm


TJ> Lens Two.

+Edge thickness would have to be negative! (or centre thickness
more than 8.8mm) or the glass has an index well above 2.0.

-- 

Best regards,
  Richard in the UK

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References:
- Re: [ATM] Reverse engineering a lens.
  - From: "Thomas Janstrom" <tomjan@ozemail.com.au>

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