LONG PERIOD FIBER BRAGG GRATINGS WRITTEN WITH ALTERNATE SIDE IR LASER ILLUMINATION

摘要

A method of optical fiber manufacture involves the writing of a grating on the fiber (24) using a laser. A first laser beam (48) is directed on a first locality of the fiber having a circumference. A second laser beam (52) is then directed on a second locality circumferentially displaced from the first locality. The first laser beam may be the second laser beam. In this way, a grating is formed on the fiber. The fiber may have a core and a cladding layer. The fiber may also comprise two gratings to form an interferometer.