A flexible fabrication technique of long-period fiber gratings using a tilted amplitude mask

Abstract

A method to control resonant wavelengths of a long-period fiber grating is proposed. An amplitude mask is tilted relative to a fiber, and the fiber is irradiated through the mask. Using a mask with a grating period of 460 /spl mu/m and a KrF excimer laser, a tuning range of 329 nm was obtained for a resonant cladding mode by tilting up to 45/spl deg/. It has been possible to fabricate a long-period fiber grating having resonance at any wavelength in the range 1.2-1.6 /spl mu/m using only an amplitude mask.