In this book, the optical properties of chalcogenide photonic crystals were discussed using PWEM, TMM approaches. The studied is further extended to analysis the fundamental approaches to study the transmission, reflection and band structure. The defect structure has been discussed in 1-D and 2-D PC structures to study the effect of various parameters on optical transmission. Then, the various potential application of photonic crystal discussed as optical cavity, optical waveguides, optical filters, optical band, optical splitter, directional coupler, demultiplexer and so on. At last, the...