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by dekhn 2668 days ago
BTW, this reminds me of an easy way to make a GRIN lens: http://www.laurawaller.com/opticsfun/sugarGRINlens.htm
1 comments
aidenn0 2668 days ago
That's neat; a friend of mine made a GRIN lens by letting gelatin set in a cup on a turntable; the density increased with the radius so it acted as a concave lens despite being disc shaped.
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