Could I build a giant magnifying glass? (And maybe incorporate it into a steam engine?)
The sun has a lot of power, and I want to harness that energy, and try out a few things, including the interesting prospect of using it to power a steam engine. (Heat up something, run water over it, and run the steam through a turbine).
Several methods have come to mind, including: acrylic, freezing some water in specially-shaped bowls, and sandwiching water (which has a slightly higher refractive index than ice) between two parabolic pieces of plastic. I'm personally concentrating on the last one, as it would be more permanent than the ice.
Just thought this up: freezing a lens, and then coating it with something immediately so that it will stay once it melts. What do we have that is clear, dries quickly, and readily available?
Does anybody else have experience with this?
UPDATE: Some relevant links...
An ideal result.
Parabolic mirrors are another possibility, but I'm still more interested in a lens.
Where a lot of this sprang from.
Indices of refraction. Is it Indices or Indexes?