From: "Richrad" 
To: 
Reply-To: "Richrad" 


Generally, how do you measure the index of refraction of glass?

I think you can do it with a microscope that has a calibrated vertical motion.

You need a small flat sample of glass with polished parallel surfaces.   Put
a piece of paper under the glass, and focus on it.   Then put the glass on
the paper, and focus again.   The shift in focus and the thickness of the
glass tell you the index of refraction.   Do this with light of various
colors, and you might be able to measure the dispersion.

As usual, the details are left as an exercise for the student.

Another method might be to make a small lens whose surface curves are very
accurately known.  Measure the focal length at different wavelengths, and
do the math.

To identify the glass, you might try to measure its physical properties,
such as density, thermal expansion coefficient, etc.  This works best when
there are only a few possibilities.

. . . Richard

----- Original Message -----
From: "Thomas Janstrom" 
To: "atm" 
Sent: Tuesday, January 14, 2003 4:12 AM Subject: ATM Corning optical glass


>
> I have just come into a lump og corning optical glass, I want to find out
> some of the numbers for it.
>
> This is the info I do have on the glass.
>
> Glass type: 523-586
> Tank: 137 FA Cord:C (this last bit is a guess as the writing is faded)
> Date: 12/29/60
> Hour: 0000
>
> How would I go about converting this info to some thing usable to the
> designing a system that uses this glass?
>
> TIA.
>
> Clear skies, Thomas
> http://www.tjanstrom.com
> "Don't make me set the laser printer to stun"
>
>
>

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