تأثیر عملکرد همبستگی بر روی سوئیچ کانونی یک پرتو منسجم

It is known that the phenomenon of focal switch depends on the Fresnel number of the lens system, coherence, polarization and amplitude of the incident beam. In this paper, we investigate the influence of the correlation function of a partially coherent beam on focal switch. We study the intensity distribution of an elliptical multi-Gaussian correlated Schell-model (MGCSM) beam focused by a thin lens. It is found that focal switch occurs and we can effectively control focal switch by modulating the structure parameters of the correlation function. Our results provide a novel way for manipulating the focal switch of a partially coherent beam by engineering the structure of the correlation function.