This book presents a study of optical filtering characteristics of 1D all dielectric and dielectric-metallic (metallodielectric) photonic crystals. The results of this study are useful for designing optical band pass filters in different regions of the electromagnetic spectrum by using 1D periodic photonic crystal structures. A detailed analysis of effects of various structural parameters on output spectra of filter is presented here. By knowing the effects of these parameters, one can control these parameters to utilize these photonic crystal structures for optical filtering in a desired and optimum way.