Group-delay-tailored chirped fiber Bragg gratings using a tapered elastic plate

A new method to induce a strain gradient on a fiber Bragg grating is described. The method can be used to generate arbitrary strain distributions along the fiber. The objective of the method was to apply strain to a fiber grating that is attached on an appropriately tapered elastic plate. Using this method, linearly/nonlinearly chirped fiber gratings were prepared. Various group delay slopes were obtained depending on the plate shape and the applied strain. In addition, the repeatability could be maintained by adopting a feedback control method for the strain adjustment.