Method of making an index grating in an optical fiber, and a quasi- distributed array of sensors formed in said fiber

摘要

An array of sensors quasi-distributed in an optical fiber (10), the sensors being delimited along the fiber by intermode coupling zones which are made by exposing the optical fiber (10) to a laser beam (16) through a mask (18) having periodic spatial transmission tuned to the difference between the propagation constants of the two modes to be coupled.