IR fluorescence

[Dr_Evil]

This has been something on my mind lately. We all know that UV up until around 450nm can cause things to "glow." I know IR isn't really "visible" although some can see IR that is near the red area on the spectrum. What would happen if you were to shine 808nm onto something that is 10600nm though? Would it cause a similar reaction? Any thoughts as to why or why not? What about if something around 365nm was shined onto something around 10600nm? Do you think it would fluoresce at something in the visible spectrum?

 

[Sigurthr]

While you're talking about something that exists, you have a flawed statement in there that is causing problems:

"something that is 10600nm"

Things aren't a wavelength. Things can emit or absorb a particular wavelength, but they never emit or absorb only one wavelength.

Now, things can absorb a shorter wavelength and emit a longer one, this is true fluorescence. The longer wavelength emitted can indeed be in the IR region, it can also be in the UV region, and even the xray region (called XRF). You can even have a quasi-fluorescence where a material absorbs light and then emits a shorter wavelength when struck with a longer wavelength, this is how the IR visualization cards work. This isn't true fluorescence though and is actually a type of phosphorescence. You also have Raman scattering, which is very similar to fluorescence.

 

[The Lightning Stalker]

Ooh, ouch, okay.

I'm not sure if this is what you are thinking,
but here it is.

808nm hits an Nd:YAG crystal, Nd in said
crystal then fluoresces at 1064nm. Both IR
wavelengths we cannot see very well

Then there is what is known as anti-stokes
fluorescence. This is where 2 or more
photons interact to produce a single photon
of shorter wavelength. 1500nm hits
phosphor card, said phosphor card then
fluoresces at 550nm.