Richard J Kinch wrote:
Christopher Tidy writes:


but I just thought I'd ask here in case anyone can
think of a source for a small piece of semi-silvered glass or plastic.


Inexpensive if you can find what you need:

http://www.surplusshed.com
http://www.anchoroptics.com/

Has what you need and charges accordingly:

http://www.edmundoptics.com/
http://www.mellesgriot.com/
http://www.thorlabs.com/
http://www.newport.com/

Thanks for those links. I took the reflector frame out of the microscope
today and measured it. Looks like the piece of glass needs to be 1" in
diameter and 1/64" thick, though a thinner piece could possibly be used.

According to some articles I've found online, certain metallurgical
microscopes use a plain glass sheet which works by total internal
reflection rather than a semi-silvered mirror. If that's the case with
my microscope, it would make the glass much easier to find. I might even
be able to use a circular glass cover slip.

Then there's the problem of fitting the spring clip over such a thin
piece of glass without breaking it. I figure I should order several
pieces of glass!

Best wishes,

Chris