Re: ATM ? Test for Strain in Coated Mirror

["Jan and Rod Shea" <jnrshea@comcast.net>]

Very sorry for all the multiple posts, including the one in html. I thought
I was having a problem with my email address and the server, apparently not.
My apologies.

Rod


----- Original Message ----- 
From: "Jan and Rod Shea" <jnrshea@comcast.net>
To: <atm@shore.net>
Sent: Friday, October 24, 2003 7:53 PM
Subject: ATM ? Test for Strain in Coated Mirror


>
> Hello All,
>
> Does anyone out there know a way to test for strain or annealing problems
in
> a coated mirror?  Can you shine polarized light at the back of the mirror
> and look at the reflection off the back of the coating through a
polarizing
> filter?  Would this double pass through the glass change what I would see?
> I am also having a little bit of trouble rigging a 1.25" polarizer onto a
> flashlight and getting a beam wide, bright, and even enough for this 24"
> mirror.  Seems like I could get a large polarized screen, or try a
> reflection from a large, flat, second surface mirror once the sun comes
out,
> but has anyone else come up with a simpler way?
>
> Thanks,
>
> Rod
>
>
>
>