Investigation of parameters of the Bessel beam formed by an axicon

Optical tweezers use a special class of light beams – the so-called Bessel beams. The field amplitude of these beams is described by the Bessel function of the first kind of a zero order. The traditional method of forming zero-order Bessel beams involves the use of a classical optical element – a conical axicon lens. We designed and assembled an experimental test bench to study the parameters of the Bessel beam formed by the axicon. In the course of experimental studies, it was confirmed that Bessel beam is a diffraction-free beam. In addition, an influence of a divergence of the Gaussian beam at the axicon input on the parameters of the Bessel beam was investigated. The transformation of such a beam by an optical system was considered. It is shown that when the Bessel beam is transformed by an optical system, the principle of similarity of optical fields in the optical conjugate planes is fulfilled. The results of modeling the formation of the Bessel beam by the axicon obtained in this work are consistent with the experimental studies.