Acoustics: Sound Fields, Transducers and Vibration, 2nd Edition

13.12. The Babinet–Bouwkamp principle

Kirchhoff theory

In its original form, Babinet's principle [34] simply states that the diffraction pattern resulting from the transmission of a plane wave through an aperture in an infinite screen is equivalent to that produced by the scattering of the same incident wave by the complementary disk. In the Kirchhoff theory of diffraction [35], it is assumed that the screen and complementary disk are either both rigid or both resilient, in which case the field scattered by an aperture in a rigid screen or complementary rigid disk can be represented by radiation from a rigid piston in an infinite baffle. Similarly, the field scattered by an aperture in a resilient screen or complementary resilient disk ...