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ArcticMyst Security by Avery
Can humans see 940nm IR ?
- Thread starter Shobos
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ARG
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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.
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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Sigurthr
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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.
I used camera and IR filter, it didnt show any light from LED, so it means I am seeing IR ?
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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.
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 !
ARG
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You can find out with an optical spectrometer, but they're not cheap.
