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Can humans see 940nm IR ?

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Hi, are humans suppose to see 940nm IR ? I recently brought 10 IR 940nm off ebay, and when i turn them on they all seem to be very bright dark red, like cherry red. Are we suppose to see IR ? seems kinda weird
 





We can see low wavelengths of IR in high power densities.

As we go past the visible spectrum the perceived brightness just gets lower and lower until it can't be seen anymore, regardless of the power.
 
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LEDs have poor spectral purity and emit a ton of unlisted wavelengths. Chances are you aren't seeing the 940nm but something <850nm that is a spurious emission. You would need an IR pass filter to determine if you are actually seeing the IR.
 
Sigurthr said:
LEDs have poor spectral purity and emit a ton of unlisted wavelengths. Chances are you aren't seeing the 940nm but something <850nm that is a spurious emission. You would need an IR pass filter to determine if you are actually seeing the IR.
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I used camera and IR filter, it didnt show any light from LED, so it means I am seeing IR ?
 
I've played with a few 940nm IR LEDs, and they are nearly impossible to see. Sounds like they might have sent you 850nm by mistake.
 
Cyparagon said:
I've played with a few 940nm IR LEDs, and they are nearly impossible to see. Sounds like they might have sent you 850nm by mistake.
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As I can guess these is no way of finding out, right ? Ill show LEDS to other people to see if they can se the light too ! THanks for info !
 
You can find out with an optical spectrometer, but they're not cheap.
 
ARG said:
You can find out with an optical spectrometer, but they're not cheap.
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HAha, i think ill pass ! I asked my grandpa he could see red clearly so yeah those are not 940nm.... Thanks for help ! 1 rep for you !
 
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