Visiblity help!

[Alaskan]

I have IR and lots off it, all together about 1000 watts of it between my different lasers, but it still scares me.

 

[CurtisOliver]

IR is scary. It is so easy to underestimate it simply because you can't see just how bright and powerful it is.
You sure do have lots of IR and a lot of power Alaskan!

 

[Alaskan]

It is quite a lot for average power, pulse power, now that's a different story, millions

 

[CurtisOliver]

I don't think we should go there with the pulse power.
You could probably achieve this if you combined all your IR's together.

 

[Alaskan]

Now that takes a few magnitudes more average or pulse power than I have.

 

[CurtisOliver]

Lol, yes but if you keep collecting like you do, then I wouldn't put it past you.

 

[Radim]

It is really hard to say as all of mentioned wavelengths are in that tiny tail of the luminosity function. Therefore I guess it is highly individual. But I can definitely see IR from TV remote and even from my 532 nm 800 mW when batts are low and it is below lasing treshold, even that is IR filtered. But it is extra dim. I noticed when I used some Ultrafires without protection - dangerous I strongly recommend not to do it. I do not use them anymore, only protected batts, which cut it off when 532 nm output is still lasing.

 

[Alaskan]

I understand now, I've heard of people who can see longer wavelengths, as well as others who can see shorter the average individual can't. I cannot see a hint of light from an IR remote, none.

 

[CurtisOliver]

It depends on the remote, some may use 780nm laser diodes meaning that they are more visible than the 808 and 850's. If it isn't 780, then it is most likely to be an 940/980. Longer wavelengths are unlikely to be visible to anyone, unless you are gifted with a longer range of perception.

 

[Radim]

Yes, depends on which one you use. Check this for more.
I think people in general can see UV, but cornea filters it, but if you have a cornea transplant, it is possible to see it. I've read that some people might even recognize polarized light or see more colors as they have some kind of mutation making them tetrachromats.

 

[Atomicrox]

850nm really is hitting the edge of what our eyes can see. And 7mW is not much. Have you got IR vision Atomicrox? :thinking:
Exactly how dull are we talking? 10W of 808 appears dimmer than around 1-2mW. 7mW of 850 would probably be like looking at 60-70nW (0.06-0.07 µW) of 650nm.

I'm surprised you see a dot from 7mw of 850nm, unless focused to a very tiny point, or was it?

IR isn't as hard to see as most luminosity curves show it to be, there are lots of posts here of people seeing different IR wavelengths. I can see 780, 808 and 850 just fine. They all look dull-red, 850nm being a different shade from 808nm. The 850nm definity looks much lower power than any red laser I have, but it's hard to estimate.

OTOH I can't see 980nm at all.

 

[Alaskan]

I can see 808nm if the power density is high enough; dull red. What I understand is happening is, since we do not have an IR color cone, if the red color cones of our eyes get excited enough by the IR energy we think we see that wavelength, as red, when it is really invisible and we aren't seeing any color at all from that wavelength, not really.

 

[Atomicrox]

By definition it's not invisible if you can see it. Our color perception cutoff is not as sharp as most think, it fades gradually. I remember seeing one account of an experiement where a test subject could see laser light above 1um when shined directly into his eye.

 

[steve001]

It is possible to se IR down to 1064nm.
https://www.osapublishing.org/josa/abstract.cfm?uri=josa-66-4-339#Abstract

There's this too.
Humans Can See Infrared Light, Scientists Say | Biology | Sci-News.com

 

[paul1598419]

I have never even heard of anyone who can see the IR from a remote transmitter. It is very low in power and not at all collimated. I have to use a card to see it myself. All of them are LED based and modulated digitally to be used by the remote receiver.

 

[Atomicrox]

I can see IR from many (but not all) remotes just fine. Not only remotes, but from those cameras that use IR LEDs as illumination as well. A few smartphone face-distance sensors are visible as well.