Tuesday, March 12, 2013

OK, that's hot! - and I want one!


Via an article in the Daily Mail, we learn of the creative instincts of one Grant Thompson.  His YouTube channel has many videos of his various and sundry projects, but the one that caught the newspaper's imagination (and mine) is the way he used a four-foot Fresnel lens from an old rear-projection TV set.  As background information, he describes acquiring and extracting it in this video clip, and making a frame for it in this one.  Here's how he put it to use after those preliminary efforts.





I was going to say "Cool!", but that'd hardly be appropriate in this case, would it?  Now, where can I find one of those old rear-projection TV's?



Peter

5 comments:

Murphy's Law said...

I'm thinking that with a vehicle mount and a couple of mirrors for energy redirection, I could have something really handy for traffic wars. Might need a prism to refocus it at range, but there's some possibility there for sure. Maybe one or two of them above my driveway to create an energy barrier that gun-confiscaters and Jehovah's Witnesses can't pass through.

Anonymous said...

If you'd care to think a bit smaller, you can get different (smaller) sizes here:

http://www.scientificsonline.com/catalogsearch/result/?q=fresnel

Somewhere I still have one of the credit-card size lenses, and it will start a fire instantly on a sunny day. The 11" square one they offer is adequate for a solar cooker.

Goatroper

Wraith said...

Peter, check your local thrift store/Goodwill. I've seen a few Humungotrons at those places, and they're available at a bargain.

Toejam said...

Heck, this is nothing new.

Archimedes demonstrated the power of the sun focused by parabolic mirrors in 212 BC. (remember that Old NFO? I do.)

Heck, the radio hadn't even been invented then let alone television.

Billll said...

Murphy is right. A collimation lens to straighten out the converging rays and a couple of steering mirrors, and you'd be dropping squirrels off the telephone wires, pre-cooked, into your dogs mouth.
Great entertainment on an otherwise dull day. Try not to hit the wires.