الفهرس 
Chapter 1: IntroductionOnly 14 pages are availabe for public view
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Abstract
Free space optics have been considered the topic of the day and have a large variety of applications which free space separates the source from destinations such as External Cavity Tunable Laser (ECTL). In ECTL, laser source emits a Gaussian beam that propagates in plane with substrate until reaching the external reflector. The efficiency of these applications depends on the amount of light that is coupled back to the laser, called coupling efficiency. Increasing coupling efficiency depends on using assembled lens’s or any optical part in the path between laser front facet and external reflector, which result in increasing the cost and integration effort. Micro electro mechanical system MEMS mirrors are very promising candidates for ECTL sources and optical switches. MEMS aids in the design and the fabrication of optical switches. It introduces scalable optical switches. When using the Deep Reactive Ion Etching (DRIE) technology, micromirrors can be monolithically integrated with their actuators on a single Si die. We propose here a new configuration of external cavity tunable laser based on micromirrors that called dual ECTL. The usage of cylindrical and spherical mirror affects on the amount of light that coupled back to laser and that decreases the alignment requirement in the laser assembly as compared to other configurations based on flat mirror. The fabrication of cylindrical mirrors is simple with respect to the spherical mirrors. So it can be used in batch fabrication. Tuning can be achieved by using MEMS technology. The system consists of a laser cavity and a two filter cavities for wavelength selection. The formation of mirrors microstructures was made into the substrate volume. So we report also the micromachining method that is used for fabricating the curved and spherical mirror. Anisotropic etching and DRIE are especially useful for the batch fabrication of large optical mechanical devices. The characteristics of the laser’s spectral response versus laser facet reflectance variations are described via simulations. The diffraction of light in ECTL formed by the laser front facet and the external reflector is taken into account. Here we report all considerations about the model, including the fabrication steps and simulation analysis.