| 摘要 |
A fiber optical coupler comprises a bundle of optical fibers configured to couple light from a multiplicity of input light sources to an output port, each of the fibers comprising a multimode fiber having a core region and a cladding region surrounding the core region. The bundle has first and second axial sections arranged in tandem and adiabatically coupled to one another via a transition zone that includes an optical interface. Within the first section, the ratio of the cross-sectional core area of each of at least some of the fibers to the total cross-sectional area of each of those fibers is given by R1, and within the second section, the ratio of the cross-sectional core area of each of at least some of the fibers to the total cross-sectional area of each of those fibers is given by R2>R1, where R2 is substantially constant along the axial length of the second section. In one embodiment, the second section is tapered from a larger diameter at the optical interface to a smaller diameter at the output port. Methods of making such optical couplers are also described. |
