2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/226779Fourier transform is applied to annular beams of simplified flat two-level geometry: bright outer ring with a darker core. The pattern of focal beam profile (i.e. far field) is calculated and characterized with respect of its intensity structure. Specific behavior is observed for extreme annularity values.7 pages, 8 figuresOpticstext