Propagation characteristics of Bessel beam using phase type CGH

Abstract

Bessel beams are a special class of diffraction-free solutions of the wave equation which are of practical interest, for example, in precision alignment, laser machining and laser surgery. Therefore efficient methods for the transformation of a Gaussian laser beam into a Bessel beam are needed. We design and fabricate computer generated holograms(CGH) to generate this Bessel beam. Designed CGH is recorded onto the photopolymer which is used as a volume hologram material making CGHOE(computer generated holographic optical element). The principle of the CGH and the propagation characteristics of the Bessel beam are explained. The binary mask designed for generating Bessel beam is copied on photopolymer by the contact copy method. The axial intensity is measured for the beam propagation distances. The propagation property and the intensity profile of the Bessel beam are analyzed.