Lots of people build mirror-based solar ovens. I'd like to build one with transparent plastic.
The lens is simply a water-balloon supported by rigid 'ribs' made out of sturdier plastic to give it shape. When water is pumped into it, it assumes a lenticular shape and allows you to focus light wherever you wish.
Perhaps a portable, mostly plastic solar salt-water-distiller could be built using this.-- cowtamer, Nov 20 2008 (?) Water Filled Jugs causing Fires http://www.dflt.org...ness/water-jugs.htm [cowtamer, Nov 20 2008] Halfbakery: Fly eye water lens Fly_20eye_20water_20lensThe idea is for something else, but the first annotation mentions water-filled plastic lenses. [jutta, Nov 20 2008] //Perhaps a portable, mostly plastic solar salt-water distiller could be built using this //
Finally feasible or not, I just love the attempts to apply simple but powerfull ideas like these to real life problems.
Ideas like these thrill me much more than Minority report like screens.-- kamathln, Nov 20 2008 I love it, but a quick Google of "solar water lens" brings you to an article that says this is VERY baked or solar cooked in this case. Maybe I will bun if you can come up with an original detailed design, but the basics are baked.-- MisterQED, Nov 20 2008 //it assumes a lenticular shape and allows you to focus light wherever you wish//
It's where you wish as long as it's underneath your water balloon somewhere, depending on the position of the sun. And forget about the ribs. What you need is a cross-section that varies in such a way that the weight of the water deforms it to give the proper shape. Otherwise, you won't have much of a focus. If you make it out of rigid plastic, then you don't have to worry about deformation, but that's been done.-- ldischler, Nov 20 2008 Excellent idea, except that water absorbs IR wavelengths really well.-- hippo, Nov 20 2008 random, halfbakery