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ArcticMyst Security by Avery

1W 808nm for night vision

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Seal team 6? Really? C:cool::cool:L
Seals using 808nm... They can't afford better? Hell any laser at all during an massively important mission like team 6's could compromise them.
 
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Aug 19, 2011
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I don't know if I'm being an idiot, but... is the way that 317 is wired wrong? I thought it was different. Unless this isn't a DDL driver.
 

Fiddy

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been a while since Ive played with the 1W IR diodes.

decided to make some additions to the custom driver i built.

Added a heatsink for the LM317T
Added some capacitors:

808nmNegativeRegulatorDriver-1.png



I also bought 2x of these drivers: 1 Pcs 808nm 1W Laser Diode Driver | eBay

They claim up to 1.2A output, with one with the pot wound up it maxed at 380mA lol
The test load i used was 3 diodes in series with the 1 ohm resistor.

I ended up using 2 of those drivers in parallel and it was making ~500mW on the LPM

1WIR.jpg



The beam is pretty nice under NV power wise you can see it quite well, the beam profile is similar to the 1W 445nm's but invisible to the human eye, even at 500mW.

I could see it hit a ridge which is about 2km's away.
 

honeyx

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Fiddy, you can use this driver you were using previously for this diode. All you need is to solder a secound sink resistor in parallel to the existing one and heatsinking the transistor. This way i was able to feed such a diode with 1.2-1.4A by using one Li-Ion battery.

Oh I noticed the other driver is the same, just a different layout and a bigger D882 transistor. So you can modify it the same way to get more current. Heatsinking this transistor should be even easier due to a larger surface.

Btw. It´s still a linear driver simmilar to a LM317 but using an OpAmp and a sink resistor. So you can measure the current between the battery and the driver while turning the pot.
 
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honeyx

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You mean the resistor? I think they are 0.3 Ohm each, so two of them will be 0.15 Ohm.
 
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Fiddy: This is why I don't like test loads. They just confuse people more and then they use them incorrectly. At that current, your test load will drop 4V - not a realistic approximation for an IR laser diode. Use a Li-ion like they suggest, and drop it down to one diode or just put your ammeter on the output.

Also, the polarity on your lm317 circuit is backwards, and the voltage is nowhere near enough.
 

honeyx

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Fiddy: This is why I don't like test loads. They just confuse people more and then they use them incorrectly. At that current, your test load will drop 4V - not a realistic approximation for an IR laser diode. Use a Li-ion like they suggest, and drop it down to one diode or just put your ammeter on the output.

Also, the polarity on your lm317 circuit is backwards, and the voltage is nowhere near enough.

Exactly. That´s why I prefer to use OpAmp based sink drivers for them. They have a lower voltage drop, are designed for case positive diodes though you can use them with case nagative diodes too, can be feeded by just one Li-Ion battery and seem to be more stable than the LM317 drivers. At least for me a lot of LPC815´s died by using a LM317 driver but not with an OpAmp based one. You can also simply modifiy them to run up to 1.4A and measure the current between the driver and the battery so no testload is needed.
 
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Hi fiddy
I'm interested in filming at night, I use a Sony camcorder with nightshoot.
Me and some friends have been using IR lasers. The problem we have is the IR light is not clean, it looks like your looking thro a chain link fence.
We have seen someone using IR led illuminators, And the light is clean and is a lot better for filming.
I'm interested in replacing a 1watt led from a torch with a 1watt IR led. I've never done any thing like this before. I'm aware of the dangers of IR and would wear eye protection while building the IR led into the torch.
Is it a matter of just taking out one led and replacing it. Size for size.
Any guidance from your self and forum members appreciated.
Or can I buy a 1watt IR led 808nm - 850nm hand held torch.
Cheers Kevin
 

Fiddy

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hey man,

it depends on the current rating of the Diode(s).

The forward voltage for a IR LED is around 1.5-2V, which is less than your normal T6/Q5 leds which is 3.3 - 4V, so it will be fine.

If the LED torch's driver current is equal to or less than the maximum current for the IR diode then it will work.

If you get one that fits even better!

Fiddy.
 
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Great video Fiddy! Thanks for posting it. I must have forgot to comment when I first saw this thread. :p
What do you use to drive your IR laser diodes? I know people use flashlight CC linear drivers for 445nm but it feels risky to me since I don't know how resilient my IR diodes are. Heruuscience diodes but tested by RHD 990mW@1.25A 825nm & 740mW@1.18A >825nm.
 
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Fiddy

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THanks mannnn!
Im using a custom built negative regulated LM317T Constant current at 1.25A :)
 
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Hi fiddy
What you reckon to this, I've decided to buy a complete unit.

Spiderfire X03-IR 3W Infrared LED Flashlight Surefire | eBay

I've ordered this and I'll test it out with my Sony nightshot camera. I'll let you know how it performs. I've ordered a 1watt IR led, so when my 1watt led Torch arrives I'll have a play and see if I can swop the LEDs to make a 1watt IR led illuminator for night vision.

I'm looking for a lens so I can also tighten the beam for long distance. I was thinking of fitting the lens onto a tube that fits over the torch head. That can slide back n forth for beam adjustment. Did you sort out a lens.
Cheers craggrat
 
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Dec 24, 2011
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Hi stathmarxis
Thanks for the link. I've emailed them for more details.
What is the beam size at 30meters and 100meters. And is the light clean. On your 3watt Izlid.
I'm enquiring about the 1watt Ciris, only need light out too 200 -300meters.
Cheers craggrat
 




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