Material that fluoresces under IR?

I work with a lot of fiber-based communications, ie: Gigabit fiber, SAN, etc. Right now my method of finding the fiber connected to the transmit side of the connector is to kind of look askance at it & hope that I can see the slightly glowing fiber before I burn my retina out with the laser.

It’s not smart.

Is there some plastic-like material that I can get that I can just shine my fiber pair onto/through that might make it easy & safe to identify the hot side?


Do you have a digital camera? A lot of them can see IR. If you do have one, look at the LCD screen (assuming non-SLR) and point a remote at it. If you can see a white dot on the remote when you push a button, you camera can see IR (or rather it doesn’t filter it out). If you have an SLR, you’ll have to take a picture of the remote while pusing a button and then look at the results.

the problem with trying make something fluoresce in the visible is that you have to put a photon with [i[more* energy in it than the visible photon that will be emitted. Infrared (IR) photons have less energy than visible photons, so you can’t simply have one produce a visible photon.
There are IR fluorescing cards that can be used with IR lasers and other high-power IR sources. The trick here is that ambient room light provides visible photon energy that kicks the system into a metastable state that high-energy Ir photons then knock them down from Here’s one example:

Another dodge is to use an IR viewer, like the Find-R-Scope viewer, available from Edmund Optics and elsewhere. These are microchannel plates that have a phosphor screen in the back that you view through a lens. It’s much like a minature TV system, using S-1 photocathode material that’s sensitive out to about 1.2 microns. They also make ones sensitive further into the IR. These are pricey.
Finally, a low-tech and low-cost method is to use liquid crystal sheets (also sold by Edmunds) to make Ir beams visible by the heat they produce when absorbed.

The way we usually ring out fiber links around here is to remove the transmitter and shine a flashlight into the fiber, then look for the light at the other end. It’s a bit safer for your remaining eye. It does require 2 people with walkie talkies, or some creative use of duct tape to hold the flashlight in place and a lot of walking.