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How to calculate lens radii by degree?

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#1 d_w

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Posted 20 January 2013 - 04:41 PM

I have read in one article strange description of the lens:

Thikness: 5mm
Diameter: 75mm
Radius: -389°; 125°


This is not misprint, in other source were written "Radius: -389 degree; 125 degree"

How to calculate lens radii by degree?

I tried to measure radii in Solidworks by drawing (first lens in doublet), it samething about -340mm and 60mm.

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#2 Mike I. Jones

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Posted 20 January 2013 - 10:29 PM

It doesn't follow any prescription convention, or even make sense. Can you post a link to the article? It looks like either a typo, or a mistake in character translation from one document format to another.
Mike

#3 Thomas Karpf

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Posted 22 January 2013 - 12:31 PM

Based on the shape of those curves, that is probably 389mm and 125mm.


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