Method for making an evanescent field coupler

摘要

A method for preparing optical fibers for an evanescent field coupler by forming a groove along a top surface of a substrate block, wherein the groove is formed shallower than the diameter of a stripped fiber. An optical fiber is positioned in the groove, wherein a center portion of the optical fiber is stripped of its coating. The optical fiber is glued in the groove, then polished to remove a portion of its cladding to form a coupling region, while not polishing the top surface of the substrate block. An optical signal is applied to an end of the optical fiber while loss of the optical signal is measured at the coupling region. Polishing and monitoring are repeated until a desired loss value is reached. The coupler can be added to an operating optical communication system.