Any fiber laser experts here?

Thank you very much! Already purchased a cheap Chinese cleaver and lapping film set, I do have a 60$ Chinese pair of laser goggles ("Eagle Pair") but I'm not sure I trust them ...

Marco Reps

Any IR is bad for your eyes (causes cataracts) Get some GOOD protection. AvE has done some really good vids on protection - he comes from the metal shop angle but IR and UV is a problem for welders. <a href="https://www.youtube.com/watch?v=FDG9Mb2O3Ec" rel="nofollow noopener" target="_blank">https://www.youtube.com/watch?v=FDG9Mb2O3Ec</a>

In answer to your questions... Yes, modules like these are typically made up of a stripe array of laser diodes in a row similar to what you see on the other end of the fiber but inside the can. One laser diode per fiber. They are typically replaced when they start losing power and emitters start dying. In the case of this module, the unit was most likely replaced due to the ends of the fibers being burnt from use and probably still has some life left in it. If the fibers are high quality, which I'm sure they are, they can be cleaved and polished and will last for a period of time but not very long at full power since the polish won't be as good as original and AR coating will be missing. You could cleave and polish a bundle of the fibers and place it in front of a collimator lens for a round and somewhat focused beam. Most importantly, these laser diodes are very hazardous to your eyes because of the near visible IR wavelength. Your eyes cannot detect the perceived brightness however this wavelength will make it right to your retina and you won't know you have been injured until it's too late. Even scattered radiation is bad at these wavelengths. It will look like a faint red glow to the naked eye. You can check if it is emitting with a cheap camera that will pick up IR LED's. You should reach lasing threshold at 8 - 12 amps with a 2.5V limit. I would highly suggest some OD5 goggles rated for 700 - 1300nm if you want to experiment further.

I've agreed to make 2 constant current drivers for equivalent modules for the guy who sent it. Good deal or bad? :)

Marco Reps

Put it in a sealed box with the fibre outputs pointing at some white paper, maybe with a piece of metal behind. Power it up for a short burst, then check if any marks on the paper. I think you'll find it is only partly working. I don't know what you paid, but the state of the fibre tips is not a good sign. And please be very careful with invisible lasers, but I think you know that.

Kean

I am a little bit scared tho, 30W invisible laser is something else than the bright blue Chinese 1W ones :|

Marco Reps

Wow! Looks very promising.

Volodymyr Babchuk