Dispersion Flattened & Endlessly Single Mode Photonic Crystal Fiber

A photonic crystal fiber with periodic refractive-index distributions is investigated for optical communication purpose. The 2D photonic crystal fiber is designed by a simple modelling method which does not require heavy computation like finite element method (FEM) or finite difference time domain method (FDTD). Since the value of d /pitch is small to realize the flattened dispersion more than 20 rings of air holes are required in the cladding region to significantly reduce the confinement loss. We designed the photonic crystal fiber having flattened chromatic dispersion over a wide wavelength range from 900 nm to 1800 nm by taking d1 d2 and pitch into consideration.