Analysis of Bessel beams through theoretical, numerical and experimental methods

With the development of technology, the use of lasers has become widespread in many areas. Lasers with many fields of study are especially used in scientific studies and industry. In addition to biomedical imaging, in non-linear optics, in micro-processing, beam shaping is often seen in many other areas. In recent years, many studies have been done on shaping the laser beam. Gauss, Airy, Bessel and Bessel-Vortex beams are the most prominent of these special beams. Among them, Bessel beams are very popular with their diffraction-free and self-repairing properties. By witnessing breakthrough developments, the optics has gained a different dimension with the discovery of Bessel and Bessel-Vortex beams. These beams remain focused for longer distances and prevented the Gaussian beam from being able to move through the diffraction. They can be obtained using different optical methods. However, using Axicon is more preferred in terms of convenience in experiments and energy efficiency. In this thesis, Bessel and Bessel-Vortex beams are experimentally obtained and characterized. Moreover, experimental results are then compared with mathematical calculations. The experiments are conducted with both the coherent sources and in-coherent sources. For this purpose, different sources with different wavelengths are studied with lasers and LEDs. When we look at the literature, it is seen that the studies are mostly with coherent sources. Therefore, this thesis will contribute to the literature and expand the application areas in which in-coherent sources are used. KEYWORDS: Beam shaping, Gauss beam, Axicon, Bessel beam, Bessel-vortex beam