Method of modifying an optical waveguide and waveguide so modified

摘要

A method of structurally modifying a silica monomode optical fibre (4) by launching optical power into the fibre (4) from a Nd:YAG laser operating at 1.064um and raising the temperature of a portion of the fibre (4) by bringing a metal film (12) into contact with a polished half-coupler block (6) to absorb energy from the laser (2). A structural modification of the fibre is initiated which propagates towards the laser (2) sustained by the optical power. It provides a means of decommissioning an optical fibre. The modified optical fibre (4) has regular periodic damage sites which can be used to form a diffraction grating. The method may also be used as an optical power limiter to protect optical networks from too high optical power inputs.