Patent ID: 6148129
Filing Date: 2000-11-14
Classification: G02B

Abstract:
A fiber optic coupler of first and second optic fibers, each optic fiber having a core and a cladding, said coupler comprising:a length of said first and second optic fibers, said first optic fiber along said length having a different propagation constant than that of said second optic fiber, said length having two ends, said first and second optic fibers twisted together at each end and substantially parallel to each other between said two ends;a portion of said length of said first and second optic fibers fused between said first and second ends, said fused portion disposed between and separated from said first and second twists;whereby an input light signal to said coupler is split into output light signals in a predetermined coupled power ratio on said first and second optic fibers, said power ratio relatively insensitive for a predetermined range of wavelengths of said input light signal.