CD's as parabolic mirrors?

From: John Tinker <>
Date: Mon Dec 11 21:24:58 2000

Chuck McManis wrote:

> >But why would it appear concave from the label side, and convex from the
> >data side?
> Come on folks, think about this! CD's are slightly parabolic to the label
> side because the darn CD cases take moch more force to get the CD *out*
> than they do to put the CD *in*. So when you grab a CD by its edges and
> pull to get it out, it is flexed into a parabola toward the label. Many
> people push on the center area when replacing CDs in the case and thus
> never counter out this original flexing.
> --Chuck

It is also true of CD's that have never been used, though granted, my sample
is small. I'm wondering if it is possibly an effect of the metalization
process. Isn't the metalization vapor deposited?
Received on Mon Dec 11 2000 - 21:24:58 GMT

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