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FrozenGate by Avery

Mitsubishi 635nm diode divergence at 350 feet

Ash

Ash

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Here is a video I just shot of my 365mW mitsubishi 635nm from a distance of 350 feet.
The "dot" is more than 24 inches across at this distance. :p

The other lasers are a 1.1W 445nm, a 180mW 660nm, and a 65mW "cute" green. :D
 





Good dot comparison. The good old red laser has the best divergence.
 
We're still working on it. There are several options that work, but they're probably too complex to put in a handheld.
 
"Tamed" is in the eye of the beholder I think.. For the units I'm building for my projectors I'm using the method cyparagon wrote about here awhile ago, using a single coated right-angle prism. The losses are a bit high, but I've been able to see about 200mW after the aperture per diode running CW at 450mA. 200mW of low-divergence 635nm for ~$120 total ain't too bad.. While this won't work in a handheld due to fact that the beam is offset when passed through a prism, in my own opinion I don't think it's necessary to do much better in a handheld than a normal lens assembly.. In my experience it's next to impossible to tell the divergence from the operators perspective and not very easy to tell from an observer's perspective. To me these diodes seem pretty damn good for multimode reds, and I've been told by a few people that the OptNext multimode diodes currently available from o-like have slightly better beams than these Mitsubishi diodes. I have not confirmed that firsthand yet, but I have one coming to me currently, should be here in a week or so.
 
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I lold at the difference :P Still thanks for sharing. Gives an idea of how better a 445nm "dot" is.
 
Silvershot said:
I lold at the difference :P Still thanks for sharing. Gives an idea of how better a 445nm "dot" is.
Click to expand...

Lol.. and many people were sooooo worried about those 445nm beams and their crappy divergence.. I've been doing shows for over a year now using projectors with uncorrected 445nm diodes (ie no prisms, cylindrical lenses, etc... just Aixiz glass) and not once as anyone come up to me to tell me that the spot is a line instead of a dot, or that the beam is too "wide".. The only person who notices that stuff is me.. and maybe an audience member or two if they're into lasers.
 
ElektroFreak said:
Lol.. and many people were sooooo worried about those 445nm beams and their crappy divergence.. I've been doing shows for over a year now using projectors with uncorrected 445nm diodes (ie no prisms, cylindrical lenses, etc... just Aixiz glass) and not once as anyone come up to me to tell me that the spot is a line instead of a dot, or that the beam is too "wide".. The only person who notices that stuff is me.. and maybe an audience member or two if they're into lasers.
Click to expand...

I agree with you. 445's are a cheat. For their price we couldn't ask for more.
 
Wow, the red isn't as bad as I thought it would be at all. Gotta get me one of these come xmas time. :)
 
To be fair they are worse than the 445s, I wouldn't want to inadvertently foster that idea, but for a handheld laser that you're going to shine into the sky or across a room i don't think it's necessary to get into corrective optics. I'm never one to say that there's something wrong with the pursuit of perfection, in fact those who want to experiment with optics to obtain the very best beam possible are to be commended IMO, but I don't feel bad about having a little handheld that has a bit of a wider flatter beam than normal.. still looks like a laser to me and everyone I show it to..
 
The same kind of silly-good divergence can be had from the single-mode 635nm optnext diodes too.. but they do cost a good bit more. Probably worth it actually, but I wonder if they're as robust as these multimodes are.
 
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Ok, so this is weird as it came to me in a dream (lol) so it's probably not going to work.

What about a convex lens, but with a lip around the edge?
 
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