From: "Richard F.L.R. Snashall" 
To:  atm{at}shore.net
Reply-To: "Richard F.L.R. Snashall" 




Mel Bartels wrote:
> I was asked in a private email the derivation of the deformed shape where:
>
> 1. glass considered thin meniscus of constant thickness (ex. 12 inch
> diameter, 1/4 inch thick)
>
> 2. glass supported at extreme edge (supported inward better???)
>
> 3. glass facing upward towards zenith
>
> What is the resulting shape?
>

Boy... that sounds like a familiar question (but drop the mirror part);-)

        Rick S.

> Years ago Tom Lum and I derived this - and I cannot remember for certainty
> if the shape is parabolic or spherical.
>
> Can anyone take a stab or point to articles?
>
> TIA Mel Bartels
>
>
>
>

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