MODE SELECTIVE COUPLER, METHOD FOR COUPLING OPTIC FIBER BY USING THE SAME AND COMMUNICATION MEANS COMPRISING A PLURALITY OF MODE SELECTIVE COUPLERS

摘要

The present invention relates to a mode selective coupler, a method for coupling an optic fiber by using the same, and a communication unit comprising a plurality of mode selective couplers. The mode selective coupler comprises: a first optical fiber of which a portion has a different reflective index; a second optical fiber; and a coupler including a first body having a groove which accommodates the portion of the first optical fiber having the different effective reflective index and a second body having a groove which accommodates a portion of the second optical fiber, wherein the portion of the first optical fiber having the different effective reflective index has the substantially same effective reflective index as the second optical fiber in a constant optical propagation mode, and at least one of the portion of the first optical fiber and the portion of the second optical fiber, which are accommodated in the coupler, has a cladding of which a portion is removed.