METHOD FOR THERMAL TREATMENT OF OPTICAL FIBER GRATING

摘要

PURPOSE: A method for thermal treatment of an optical fiber grating is provided to prevent a damage of a re-coating material of an optical fiber by using a partial heating method. CONSTITUTION: A multitude of optical fiber grating(G) is formed along a longitudinal direction of an optical fiber(F). The optical fiber gratings(G) are formed by using ultraviolet rays. In the process for forming the optical fiber gratings(G), an optical fiber grating formation region of the optical fiber(F) is uncovered. The optical fiber gratings(G) are formed periodically on the uncovered region of the optical fiber(F) by using a phase mask and the ultraviolet rays. A re-coating portion is formed by coating a resin material on the optical fiber gratings(G). A coating portion(C) for covering a cladding portion is formed on the optical fiber(F) without the optical fiber gratings(G). The optical fiber formation portion(G) is heated by a heater(20) using a partial heating method.