http://www.lasergenetics.eu/en/product/nd-5
Looks an entertaining project to do to me.
Any idea how to make one?
Was thinking to get (if it gets past customs):
And start improvising with lenses...
Looks like it could almost work without any work if that the defocused second beam image is anything to go by.
with a R2 LED and a big aspheric lens of at least 60mm diameter. I have one like this, I made from a foodcan. Currently there is a R5 there inside. That's also nice. The R2 made a very narrow beam, which goes about 250 meters far. The beam of the R5 is bigger, but it goes as far as the R2.
Actually it is a laser beam i'm trying to defocus a bit. They claim 400m for a laser thats supposedly around 20mW range. With a 200mW one one can wonder. For safety purposes i migh try a lower powered one perhaps. I do not want to fry my eyes trying.
about the brightnes of a defocussed 20mW laser vs a well driven R2 LED. It depends, if your project just targets messing around a bit with lasers or if you actually have intention to actually use it for hunting for example.
Messing with lasers mostly. This thing has pretty much zero spill if done correctly contrary to most led setups.