information on 808nm single mode diodes? - (making an IR nightvision laser)

I'm thinking about buying a cheap arsoft/gun laser sight and replacing the parts to output IR. For some reason, IR lasers for guns are hundreds of dollars. I know that NV sights and goggles are particularly sensitive to 800nm-850nm light, so an 808nm diode should work great. Power doesn't have to be great, I'm thinking 30-100mW should be PLENTY. The only real equirement is single mode with <1mrad would be best.

What kind of options exist for IR single mode lasers with good divergence?
What kind of lens would give good IR transmission? Does it need AR caoting (red or IR coating)?
I assume I would have a low Vf - would a linear/buck driver be best?

CD diodes are 780nm IIRC, those would be out of the question?
Because there would tons of them from DVD harvests.
Next thing would be a pump diode from an 6$ ebay greenie.
Those are 808 IIRC, with somewhere between 200~400mw max output,
which you could tone down appropriately.

anselm said:

CD diodes are 780nm IIRC, those would be out of the question?
Because there would tons of them from DVD harvests.
Next thing would be a pump diode from an 6$ ebay greenie.
Those are 808 IIRC, with somewhere between 200~400mw max output,
which you could tone down appropriately.

Click to expand...

The beam profile of the 300mW 808nm pumps is not ideal for pointing purposes.
The 780nm diodes would be great. They are easy to find, cheap and available from 5mW-300mW single mode with a nice, round, gaussian profile.
Driving it with a Flex Drive should not be a problem.

yeah, but is 780nm ideal for nightvision sensitivity?
IIRC, NV is most sensitive 800-850nm. Perhaps 780nm would have enough excitation.

Can the naked eye detect <100mW of 780nm IR?
So there are no low-power TO18 diodes that have decent beam specs?

LazyBeam said:

Can the naked eye detect <100mW of 780nm IR?

Click to expand...

Yes, but only if it is dark and you know what to look for.

LazyBeam said:

yeah, but is 780nm ideal for nightvision sensitivity?
IIRC, NV is most sensitive 800-850nm. Perhaps 780nm would have enough excitation.

Click to expand...

800-850 is probably a number they use since LEDs are common in this range. According to google, 780 might work better

Hello from a Newb!

I've modded a few flashlights, no laser builds (yet!), and will be taking delivery of my first treating laser - 160mW x 2 modules - in two weeks (when not fighting crime by night, I'm a chiropractor by day).

Anyway...I don't like the high price for IR "flashlights" either, and want to build an IR light to help out my pathetic GenI monocular (well it's the only one I've got).

RE: best wavelength for NVD use... Here's a quote I pulled from a Patent Application dated 1991:
"Referring still to FIGS 3 and 4 laser 46 is a commercially obtained component of laser illuminator 24 The illustrated laser illuminator is supplied with either a 50 MW or a 100 MW laser diode operating at 830 nanometers eg a Sharp Model LT015 MFO ."
BTW, they claim IR LEDs are good for only 500 ft. and their IR Laser will enable 1/2 mile target visibility!

Patent can be found here: Target illuminators and systems ... - Google Patents

regards,

brad wolff

780nm shows up on my night vision equipment.

If your on-board led illuminator glows red if you look at it, then im quite sure you can see 780nm and 808nm but not 980nm through the NV device, high end NV equipment use 980nm because it doesn't glow when the illuminator is on.

Some of my NV videos with IR lasers.

I'm working on the same thing, and at this point I am working on a dual wave version, where I can switch between the IR and the Red diodes, the latter to assist aiming, since these will collumate into the same beam. I got the diode from a PHR-803T to work, but I think I burned that one out. There are other similar diodes out there, I have seen them, but I don't have enough info to find another one. 780nm is visable to the eye, but only for a few feet, at levels that don't overload my nv.