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How deep can YOU see?

awlego

awlego

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How far into the IR spectrum can you see? Or how deep into the UV spectrum? I haven't had any chance to test if I can see anything below 405nm, but I have some IR LED's and I can even see a faint red glow with 100mW of 940nm light :)

Just wondering what the range of other members' vision is I previously thought "normal" was 400-700nm, maybe 400-800nm, but seeing 940nm seems pretty far into the IR range to me.
 





The red glow you see is not the 940nm light itself. Diode lasers are not known for their particularly narrow bandwidths in their emission.
 
Lowest I've seen is 355nm (very dark violet halo around the dot), highest is probably 900nm (dark red) or so, random diodes from testing Heruur batches and the 355nm was a q-switched dpss unit that I later sold on ebay.
 
It is said that people who have had their lens removed (for cataracts) can see into UV, but I don't have a pure or filtered source to test it with.
 
I can pretty easily see the IR coming from my tv remote in dimmer light conditions. I don't have a UV source to check the other side of the spectrum with though.
 
I tried a TV remote and i could just barely see the red light
 
I advise NOT to look into the remote or any other IR-source. It may be incoherent light, but it can still do damage! Might as well jam a white LED key-chain light in your eye...
 
FireMyLaser said:
I advise NOT to look into the remote or any other IR-source. It may be incoherent light, but it can still do damage! Might as well jam a white LED key-chain light in your eye...
Click to expand...

When I was like 12 I replaced the IR led with a 5mm red led and it was pulsed at a very low duty cycle and was not very bright at all. It was only a few mAs.

But I agree, it's not a very good idea to point it in your eye, even though it's unlikely to be very powerful and cause damage.

-Tony
 
Xplorer877 said:
When I was like 12 I replaced the IR led with a 5mm red led and it was pulsed at a very low duty cycle and was not very bright at all. It was only a few mAs.

But I agree, it's not a very good idea to point it in your eye, even though it's unlikely to be very powerful and cause damage.

-Tony
Click to expand...
Red LEDs require higher voltage than IR LEDs, just like laser diodes. It may not have gotten enough voltage to come on fully.
 
Nah, I can see the glow from a 5watt 980nm led. (no i will never sell it.)

Also, 50kV x-rays. No, I never looked into an x-ray tube. When I had to get a CT scan I asked doctor to turn off the lights and he said what the hell, sure. I let my eyes dark adapt for 5 minutes, and when the scan was preformed, I saw a deep blue light seeming to come from inside the eye.
 
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I can see Gamma rays, when I watched Spock reach into that radioactive source that killed him. Don't remember which movie that was though. Gamma rays are bright green. J/K
 
Uranium said:
When I had to get a CT scan I asked doctor to turn off the lights and he said what the hell, sure. I let my eyes dark adapt for 5 minutes, and when the scan was preformed, I saw a deep blue light seeming to come from inside the eye.
Click to expand...

I'll bet that was pretty cool, and a bit freaky
 
Last night I did an experiment, thinking of this thread. I have the o-Like 980nm 65mW laser, and, while I can see the 808nm version just fine, I never had been able to see the 980.

I let my eyes dark adapt for about an hour, and set up some white surfaces in my closet. Well, i'll be damned - I saw it.

And it didn't look red. It looked almost *gray-green*, and more visible in my peripheral vision than in the center. So I think I actually did see 980@65mW. I was expecting a dull red but that's not what it was at all - as if the cones weren't doing it, but the rods were.

But I definitely saw it - even if I changed the focus of the head, I could see it being defocused and focused.

Very strange, and I don't think it was broad emission either, since 808 definitely appears as a dull red to me, it must have been above that.

Uranium - That story is pretty cool, do you think the blue glow was ionization?
 
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