IR filters and IR LEDs

wykeite

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I'd like to know if anyone has experience of either of these. Critically do either show any visable light? Are there any good sources for quality non visable IR filters/leds?
 

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I'd like to know if anyone has experience of either of these. Critically do either show any visable light? Are there any good sources for quality non visable IR filters/leds?

A quality one will filter out all visible light only leaving IR to pass though. Unless you dropped a couple of grand for some NVGs you won't have much use though.

The sources depend on what kind of light you use.
 

Light Sabre

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You're gonna have to go with IR LED's, you can't see any visable light tho. Regular white LED's don't put out any red light much less IR, so a IR filter might just block all light output. Not sure if the warm white LED's put out any red or IR. You would have to check manufacturers datasheets to see what their spectrum is. White LED's are really super bright blue led's with a phospher coating on top of the LED to convert the blue light to other visible wavelengths. So the LED's spectrum is usually towards the blue end of the spectrum. That's why there are so many green, blue, purple tints to white LED's. The website LED Museum has spectrum analyzer graphs of some of the white LED flashlights.

WWW.LEDMUSEUM.ORG * THE LED MUSEUM - Reviews of LEDs & LED Flashlights - Gallium Indium Nitride UV, violet, purple, blue, aqu...

One thing that you can do, is get a IR flashlight with multiple LED's and replace one of IR LED's with one thats visible. You would have to find a visable LED that has the same Vf as the IR LED's. I have no idea what the Vf of a IR LED is.

Here's a good example that's similar to your situation. I have a few mini-mags. I had a red filter (used with a white LED) and a red LED drop in for them. The red LED dropin was at least 2 or 3 times brighter to my eyes than the flashlight with the red filter.
 
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Inliner

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I had an Osram Goldren Dragon 940nm IR led put into a mag host. If it was very dark out, you could see a faint redish dot if you looked directly at the LED. It was not bright enough to put any visible light on the ground though. The throw was incredible on that light compared to a Surefire IR filter in front of the P60 bulb.
 

Chrontius

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Just to mix things up some, Surefire filters are probably less visible than some other filters (cheapies for Airsoft). Also, longer-wavelength LEDs are less visible than shorter-wavelength IR.
 

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cuz that's the name of the thread title...?:whistle:

Because that was the what the question in the OP was. He wanted to know which source IR LEDs or IR filters produced no visible light.

So he asked if IR LEDs or IR Filters produced less visible light?

You can't put an IR filter on an LED because IR filters filter out everything but the IR.

Non IR LEDs don't produce enough IR radiation for a filter to work.

Therefore, you have to have an incandescent to use an IR filter. Therefore to break his question down in a logical and realistic fashion, what he is asking is:

Do IR LEDS or IR filters on an Incandescent produce any visible light?

It depends on the quality of the product you buy.

I can only speak for SureFire IR filters on a SureFire weapon light and did not see any visible light.

I can say that I know plenty of tactical teams using SureFire IR filters in conjunction with NVGs. The sheer number of them in use should speak for itself.

Never seen an IR LED so someone else will have to comment. I've seen members with a SureFire M1 and they should be able to tell you. I think it was Defabricator.
 
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Marduke

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So he asked if IR LEDs or IR Filters produced less visible light?

You can't put an IR filter on an LED because IR filters filter out everything but the IR.

Non IR LEDs don't produce enough IR radiation for a filter to work.

Therefore, you have to have an incandescent to use an IR filter. Therefore to break his question down in a logical and realistic fashion, what he is asking is:

Do IR LEDS or IR filters on an Incandescent produce any visible light?

It depends on the quality of the product you buy.

I can only speak for SureFire IR filters on a SureFire weapon light and did not see any visible light.

I can say that I know plenty of tactical teams using SureFire IR filters in conjunction with NVGs. The sheer number of them in use should speak for itself.

Never seen an IR LED so someone else will have to comment. I've seen members with a SureFire M1 and they should be able to tell you. I think it was Defabricator.

Or you could use a cheaper IR LED, and filter out the shorter visible wavelengths to make it completely invisible to the naked eye, and you would STILL be more efficient than filtering an incan source.
 

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Or you could use a cheaper IR LED, and filter out the shorter visible wavelengths to make it completely invisible to the naked eye, and you would STILL be more efficient than filtering an incan source.

As far as batteries go. As far as other thing maybe not so much.

It really depends on the application.
 

wykeite

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Thanks all for your replies. I'm sorry to have caused friction.

I think I'll try an IR filter and an IR LED not together of course It's a small layout compared to a SF filter and may meet my means.
 

Solscud007

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I dont have experience with a SF IR filter but I do have the DARPA DEF3C aka PKEF C. The Turbo Kroma with white, blue, and IR leds.

The DARPA DEF3C has a very dim visible wavelength. I also have the Jakks Pacific toy NVGs. The goggles have IR LEDs to help illuminate what you are looking at in absolute darkness. those IR leds have a very visible wavelength. normally you dotn notice it, but if you are playing airsoft and lurking in the shadows, your opponent can see the dim red IR LEDS enough to locate where you are and shoot you. I covered up the IR LEDS on the goggles and use the SF DARPA which has a lower visible wavelength.

In case you need clarification, the IR LEDS have a very dim reddish glow to them but do not show actual light spill onto objects.
 
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