| 摘要 |
<p>A method of thermally poling a silica based waveguide (12) comprises exposing a region of the waveguide (12) to an electric field (for example, via capillary electrodes (22, 24) inserted into holes in the waveguide); directing a laser beam (18) into the region exposed to the electric field to effect localised heating of the region via direct absorption; and scanning the laser beam (18) over the region at a rate selected to avoid heating of the region above the glass transition temperature. Reversing the electric field while scanning the laser beam (18) allows the formation of periodic poled gratings. The waveguide (12) can comprise an optical fibre.</p> |
