Spectral response of locally pressed fiber Bragg grating

A study of fiber Bragg gratings spectral shaping when a transverse force perturbs a small grating section is presented. We consider the spectral response as a function of the strain applied by a force and the affected length of the grating. The reflection characteristics are examined by a transfer matrix formulation. The prominent features observed in the spectral responses are qualitatively explained in order to gain physical insight into the nature of locally perturbed gratings. The results show that there is the potential for a new class of applications and novel devices for optical communications systems.