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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.
Feb 5, 2011. 8:30 PMorksecurity
says:
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.
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.
A real one, or a toy ? A toy one I'd make in plexiglass.
Feb 4, 2011. 1:38 PMorksecurity
says:
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?)
Feb 7, 2011. 11:58 AMorksecurity
says:
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).
I have hand ground and polished small prisms, it's very hard to get the angles spot on!!!
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