Based On The Fdtd One-dimensional Photonic Crystal Membrane System Design

Photonic crystal has become popular research in recent years. It has huge application value and broad application foreground. This paper mainly studied one-dimensional photo -nic crystal, which is composed of two or more kinds of medium that array periodically in one direction. Analysing the characteristic of one-dimensional photonic crystal's band gap by FDTD and designing one-dimensional photonic crystal's reflection membrane which has a band gap from 8 to 14 microns are the main research of this article.This paper analyzed the reason for the photonic forbidden band existing in periodic structure and elaborated the basic principle of FDTD. The program was developed to caculate the band gap of one-dimensional photonic crystal and some parameters with the photonic crystal structure related were determined. Based on the program, the characteris -tic of the one-dimensional photonic crystal structure was studied systematically. This paper analyzed the periodicity and the ratio of medium's refractive index how to influence the photonic crystal's band gap. The ways of increasing the width of photonic band gap were analyzed. Finally, the one-dimensional photonic crystal structure which has a band gap from 8 to 14 microns is designed by piling up several stacks of refractive membrane making up one-dimensional photonic crystal. Further more, simulation to the structure under the circumstance of a big incidence angle has done. The result indicates the structure has high reflectivity during wide wave band.