Re: [ATM] Resilient retention between metal cell and optical glass?

["Arjan te Marvelde" <arjan.te.marvelde@hetnet.nl>]

> So far so good.  We'll see what happens when winter gets here.

If the glass CoE is like plate, you can make the cell out of Platinum: this 
has almost the same CoE and therefore you don't need a ring at all.

Otherwise, in general such problems are a tradeoff between how much force 
you want to excert, and how much movement you allow. Less force means a 
lower spring constant, which means less determined position.
To determine size and material of the O-ring you mention, you first need to 
ask yourself how much compressive force you allow.
Differential expansion between plate and aluminium is about 15um/m.K, so for 
example take 10" diameter and a temperature range of 40K (-20 .. +20), this 
would be 0.15mm (or 0.075 on each side). For pyrex it's worse.
The force on the glass would be calculated from the O-ring properties and 
the derived amount of compression. Then choose your PDE solver of choice to 
determine the amount of deformation of the glass, in axial direction.

   Arjan 

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