I'm thinking of a project which requires powering a device with an optical fiber, but I don't know how to compute the maximum amount of power it can supply at the end.

These are the parameters I know:
- The diameter of the fiber
- The materials used in the fiber and its properties.
- The length of the fiber

  • \$\begingroup\$ How will you convert the light power to electrical power? \$\endgroup\$ – Andy aka Apr 7 '16 at 16:42
  • \$\begingroup\$ You also need to know the details of the endpoints. How much power can you transmit? What is the efficiency of the receiving end? And so on. I suspect the answer will be "not much". \$\endgroup\$ – uint128_t Apr 7 '16 at 16:50
  • \$\begingroup\$ @uint128_t, if you're free to choose the type of fiber, I'm sure it's at least a few watts. Converting that back to electrical power, though, could be fussy. \$\endgroup\$ – The Photon Apr 7 '16 at 16:54
  • \$\begingroup\$ Carlos, typically the point of failure is at the input and output facets, so the length of the fiber is likely not relevant. It's more important to know how smoothly you can polish the facets and how clean you can keep them (so the design of such a system would mostly be done by knowledge of past experience, not by calculations). \$\endgroup\$ – The Photon Apr 7 '16 at 16:59
  • \$\begingroup\$ @ThePhoton Yup, fair point. It appears that this is already a thing, but the article doesn't give any numbers. \$\endgroup\$ – uint128_t Apr 7 '16 at 17:13

You have not provided nearly enough information, but let's start anyways.

First, what wavelength? Second, how do you propose to couple the light to fiber? A fiber with a 1 mm core diameter is a pretty big fiber, but a 1 mm spot on the end of the fiber is a pretty small spot.

With that said, Thorlabs will happily sell you a 2-meter patch cord which will handle about 50 watts. And here's a company which makes cables which handle kilowatts. Laser cutters normally use fiber optic cables to transfer IR from the laser to the moving cutter head, so 10's of kilowatts should be available. That is not to say cheap, just available.


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