Ultra-Narrowband Optical Comb Filter Using Sampled Fibre Bragg Gratings

Abstract

The optical comb filters have shown tremendous application in the field of optical signal processing, wavelength division multiplexing, multi-wavelength laser, microwave photonics, etc. The sampled fibre Bragg grating is an essential device for generation of comb spectrum. In this chapter, a detailed theory on design of comb filter based on sampled-chirped fibre Bragg grating has been provided. The multiple phase shift technique and spectral Talbot effect have been explained and demonstrated for achieving narrowband comb spectrum. A special design of ultra-narrowband comb filter using Gaussian-sampled chirped fibre Bragg grating has been shown.