Browsing by Sujet Photonic crystals (PCs ) are periodic dielectric structures , on the scale of the wavelength, and high index contrast . In such an environment , the propagation of light exhibits properties, the photon can be banned some energy bands called photonic bandgap If we introduce defects in the photonic crystal, new states enabled appear in the photonic band gap , as in the doping impurities of a semiconductor. The light can be con fi ned according to several dimensions to the default and the dimensionality of the photonic crystal . The manufacture of three-dimensional photonic crystals is still poorly controlled. Therefore, we have limited ourselves in this work to the study of one-dimensional photonic crystals The objective is to study and simulate integrated dimensional structures with and without default. The light propagation in these structures will be theoretically developed then simulated using the transfer matrix method. The comprehensive study on the impact of opto- geometrical parameters on the transmission spectrum and reflection in such structures will allow us to see their various applications in the field of optical telecommunications around the wavelength of 1550 nm.