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how to make glass prism? Answered

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orksecurityBest Answer (author)2011-02-04

Obtain/cast a clear block of glass, preferably of high refractive index, preferably already molded into a suitable shape. Polish/grind//cut to shape if not already suitably shaped. Grind/polish surfaces to optical quality.

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steveastrouk (author)orksecurity2011-02-04

Ever tried it, for real ?

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Kiteman (author)steveastrouk2011-02-05

(I think he was being sarcastic)

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orksecurity (author)Kiteman2011-02-05

Not entirely sarcastic -- just pointing out that doing it right is a nontrivial project, and it's cheaper and easier to buy unless you are have special needs or are particularly attached to doing it yourself.

Actually, you can make a _small_ prism by grinding/polishing a suitable bevel into the edge of a sheet of glass. My bathroom mirror has some decorative triangular grooves ground into it, and when the light hits them right they do disperse colors.

Acrylic/plexy is, of course, easier to work than glass. I don't think you can fire-polish plastic, though.

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brin1956 (author)2015-11-05

I remember seeing a local man who ground down tv tubes into prisms. Been looking for anything like it so I can get more details.

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steveastrouk (author)2011-02-04

A real one, or a toy ? A toy one I'd make in plexiglass.

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orksecurity (author)steveastrouk2011-02-04

Or as three sheets of glass glued together, stoppered at one end, and filled with water. (Or... Hm. What's the refractive index of lamp oil? Lower or higher?)

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Kiteman (author)orksecurity2011-02-06

You can buy clear resins as well - "fake water" etc.

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orksecurity (author)Kiteman2011-02-07

Good point. I remember casting some biological specimens in plastic, back when I was a kid. (The resin used for the purpose actually penetrated the tissues and made internal details visible; impressive.) Something like that which is very transparent, polished appropriately, seems entirely reasonable -- assuming that it is a dispersive medium (which it probably is).

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steveastrouk (author)orksecurity2011-02-04

That's another classic method, for toys.

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rickharris (author)2011-02-05

I have hand ground and polished small prisms, it's very hard to get the angles spot on!!!

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rickharris (author)rickharris2011-02-05

In acrylic. A triangular container and water works.

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