Long Bragg diffraction grating manufacturing method in monomode optical fibre

摘要

The method is applied to a fibre (1) which initially is moved together with a beamsplitting phase mask (6) in relation to a laser beam (7) and a mirror arrangement (5). A first grating (4) of defined length is formed in a part of the fibre, which is then moved longitudinally until an interference fringe pattern overlaps the grating to a defined extent. A sensor (8) with a power distribution indicator (10) detects the intensity of radiation transmitted transversely within the overlap. The relative phasing of the grating and fringes is finely adjusted until a particular longitudinal distribution of intensity is indicated.