
Originally Posted by
luciday
Yes, it is technically possible to do this. A few years ago, I bought a defective fiber laser engraver and repaired it this way. The two essential tools you need are a fiber cleaver and a fusion splicer. The cleaver ensures a clean, perpendicular cut of the optical fiber, while the fusion splicer fuses the two halves together. The cleaver is relatively inexpensive, costing a few tens of dollars on AE. However, new fusion splicers start at around 1,000 USD. The high price is due to its complexity: the device uses microscope cameras to align the two fiber halves precisely in the x and y directions, then fuses them with a spark while also carefully pressing them together. I ended up buying an old second-hand splicer on a well-known auction site and repaired it. Such used units typically cost one to a few hundred USD, depending on their condition, but as with any second-hand purchase, luck plays a role. Especially for a pulsed fiber laser, the quality of the splice must be excellent. Otherwise, the laser can damage itself due to back reflection. Rotational alignment may be needed for polarization maintaining fibers. Alternatively, you could look for someone in the fiber-optic network installation field who has a fusion splicer, it will save you a lot of trouble and money for probably just a one time job. Because of the risk of back reflection, I would not recommend turning on the laser with anything other than an isolator spliced to the end of the output fiber. With a bare end, there is a high chance the laser will be damaged at another internal splice by the backreflection. These internal splices are much harder to repair and may require special materials, such as glue with a specific refractive index. I hope this gives you a general idea of what’s involved, if you have any more specific questions, feel free to ask.