Means of Coupling Light Into Optical Fibers and Methods of Manufacturing a Coupler

A pump optical coupler comprising:

• an output optical fiber for propagating optical energy;
• a pump optical fiber for propagating optical energy;
• a coupling structure for facilitating the coupling of optical energy between the pump fiber and the output optical fiber, the coupling structure comprising a tube having a taper and a wide end and a narrow end;
• a feed-through optical fiber for propagating optical energy and feeding the optical energy through the coupling structure;
• wherein the pump optical fiber is connected to the wide end of the tube;
• wherein at least the narrow end of the tube is collapsed around the feed-through optical fiber;
• and
• wherein at a location along a first length of the feed-through optical fiber, about which the tube is not collapsed, the feed-through optical fiber comprises a first outer diameter and wherein at another location along another length of the feed-through optical fiber, about which the tube is collapsed, the feed-through optical fiber has a second outer diameter that is less than the first outer diameter.

A pump optical coupler comprising:

• a pump optical fiber for propagating optical energy;
• an output optical fiber for propagating optical energy;
• a coupling structure for facilitating the coupling of optical energy between the pump optical fiber and the output optical fiber, the coupling structure comprising a tube having a taper and a wide end and a narrow end;
• a feed-through optical fiber for propagating optical energy and feeding the optical energy through the coupling structure, the feed-through optical fiber having a core and a primary cladding disposed about the core;
• wherein the pump optical fiber is connected to the wide end of the tube;
• and
• wherein at least the narrow end of the tube is collapsed around said feed-through optical fiber, with the limitation that the diameter of the feed-through optical fiber is less than the diameter of an inner hole of said narrow end and through which said feed-through optical fiber is passed prior to collapse of the narrow end about the feed-through optical fiber, and wherein this limitation is not applied to the whole length of the feed-through optical fiber.

A method for manufacturing a pump optical coupler, comprising:

• providing an output optical fiber for propagating optical energy;
• providing a pump optical fiber for propagating optical energy;
• providing a hollow coupling structure for facilitating the coupling of optical energy between the pump optical fiber and the output optical fiber;
• providing a feed-through optical fiber for propagating optical energy and feeding the optical energy through the coupling structure;
• reducing the diameter of a first length of the feed-through optical fiber;
• refraining from reducing the diameter of a second length of the feed-through optical fiber;
• tapering the hollow coupling structure, the tapered coupling structure having a wide end and a narrow end;
• connecting the pump optical fiber to the wide end of the coupling structure;
• and
• collapsing at least the narrow end of the coupling structure onto the feed-through optical fiber at locations along the first length thereof.