Green to IR

[tatman]

took out the crystals from my 20mw newwish and now it's a real cool invisible laser...ya just need nite vision 2 play w/ it.

 

[timelord]

Have you tried to burn anything with it? Or pop a balloon?

 

[Hemlock_Mike]

That outputs 808 nM now. It will show a very faint deep red output because it's at the very bottom end of your vision.
Be very careful with it or you could have night for vision. Wear eye protection.

Mike

 

[Justin]

You don't actually need real "night vision"... Almost any electronic imaging device will be able to view 808nm. I have used everything from a digital video camera to my $60 camera phone to visualize 808nm and 1064nm laser light. But still, eye protection is a good idea. That 20mW greenie of yours is probably now producing several hundred mW of unfocused IR light. Be careful!

 

[tatman]

i have tried popping/burning w/ it to no avail. hey Justin, love my Aries! several HUNDRED mw of UN-focused IR? really? it looks to be a pretty tight dot out to at least 100 yards or so. several hundred mw should burn SOMETHING! what am i missing? is there another way to focus the IR energy? i focused it by viewing w/ nite-vision and made small adjustments to the original optics, got a nice tight dot. is there more? you are right about very faint deep red...i REALLY want to burn/pop w/ it now that ya told me this stuff! i'm gonna go muddle around w/it right now and see what i can see. thank you all for your intrest and advice...i'll check back later to see what you all say and will keep you posted on my progress. also i am able to view this safely w/ a survielience camera i have that's low light capable.

 

[SenKat]

Colliminating IR is a very tricky business ! IR comes out of the diodes like a floodlight - unless they have a GRIN lense installed (I forget exactly what the GRIN stands for - but it reduces the divergence from like 25 DEGREES to 2 or 3 degrees). I think you would REALLY have to focus up close with that diode in order to get any kind of "power" from it...be careful - don't want any bad eyes !!!

 

[pseudonomen137]

SenKat - Just FYI, GRIN lenses are used to reduce the divergence in one direction/axis only normally (the fast axis is often reduced from 20-40 degrees down to 2-3 like you said), and so the other axis usually still diverges a good bit.

 

[SenKat]

Thanks for catching that, Psuedo ! I forgot about the fast axis only part ! LOL

 

[Hemlock_Mike]

My testing IR diodes from DVD's indicates that you need a lens system similar to a red. Short FL and up real close. I've used red holders and lens assemblies with good results. You can feel it and it will blister your wrist !! Hard to see that dim beam but enough to focus.
That far away lens from a greenie won't do crap because most of the beam has diverted into the chamber.

Mike

 

[Ragnarok]

GRIN = GRadient INdex

The refractive index of a GRIN lens changes as you move from the center of the lens to the edge.

Because a diode typically has "fast" and "slow" divergence axes, a properly sized GRIN lens can automatically correct both simultaneously.

 

[SenKat]

Thanks, Ragnarok ! I appreciate the sparking of synapses ! I wracked my brain for a bit over the acronym - and could NOT recall for the life of me ! (whew) Rapidly approaching 40 next month, and the brain is already truning to mush !

 

[timelord]

Thanks, Ragnarok !  I appreciate the sparking of synapses !  I wracked my brain for a bit over the acronym - and could NOT recall for the life of me ! (whew)  Rapidly approaching 40 next month, and the brain is already truning to mush !

And they say life begins at 40 ;D ;D

 

[SenKat]

[quote author=SenKat link=1172771502/0#10 date=1173277763]Thanks, Ragnarok !  I appreciate the sparking of synapses !  I wracked my brain for a bit over the acronym - and could NOT recall for the life of me ! (whew)  Rapidly approaching 40 next month, and the brain is already truning to mush !

And they say life begins at 40  ;D ;D[/quote]

I guess that would explain why my brain appears to be so underdeveloped lately ! ROFL !!

 

[tatman]

Re: Green to IR/ mush

dang it! i'm 52...no wonder i have so much trouble- i'm workin w/ damn mush! i did get the formerly green-now IR pointer to sting the crap outta the darker Tattooed parts of my lily white skin...and real quick too, still gonna try optics from a deceased red pointer. trippy thing to share: the other night i ROASTED a little BLACK spider...and was blown away when the 100mw ARIES had absolutely no effect on another spider- he was a white guy.he just kept at his little spider stuff like he never heard about lasers. wild!

 

[Proctor]

Re: Green to IR/ mush

dang it! i'm 52...no wonder i have so much trouble- i'm workin w/ damn mush! i did get the formerly green-now IR pointer to sting the crap outta the darker Tattooed parts of my lily white skin...and real quick too, still gonna try optics from a deceased red pointer. trippy thing to share: the other night i ROASTED a little BLACK spider...and was blown away when the 100mw ARIES had absolutely no effect on another spider- he was a white guy.he just kept at his little spider stuff like he never heard about lasers. wild!

Doesn't IR absorb white and lighter colors as when a bottle of coke viewed through and IR webcam is clear like water?

 

[Justin]

Tatman, glad you're enjoying the Aries! That white spider may have survived, but you may be surprised when you notice a spider walking by with 4 pairs of dark glasses and a little white cane....

Also, the absorbtion spectrum is different for every material, but since 808nm is so close to visible red you will find that dark coloured things on the green-blue end of the spectrum will work best. Try a dark navy coloured balloon or something. If your green pointer is anything like ours, it uses a 500mW IR pump diode, so be careful when you're aiming that IR laser around, it could be quite powerful. You can focus it using standard optics like a magnifying glass or something, just watch the reflections.