Re: can someone help me with this fresnel lens?
[snip]...
| but the focal point appears diffused... Since this is a lens, is
there any
| way I can add an additional fresnel (or even glass) lens at the
focal point
| to decrease it even further so I get higher melting points?
In short - not really. The fresnel lens creates a beam that is by
design diffuse. While it creates a diffuse beam, this beam can
approach parallel, thus could be configured to serve as an excellent
condenser lens (for another focussing lens). But, as you have stated
that you're intending to use the sun, you already have a diffuse
nearly-parallel beam... :)
Sorry
Al
.
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(sci.optics) |
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