Diffraction Of A Plane Monochromatic Wave At The Circular Aperture And Circular Disk

In the framework of the scalar theory of diffraction of normally incident plane monochromatic wave, the intensity distribution of the diffraction field along the axis of an annular hole was found. As particular cases, the diffraction at an opaque circular disk of radius R ب λ (λ is the wavelength) and at a circular aperture in an opaque screen was considered. Accounting for the vector nature of the field of electromagnetic waves led to more correct results, including at large angles of diffraction, i.e. at sufficiently small distances from the screen (smaller and of order R), where the scalar theory, as it is known, not applicable.