The possibility of applying an ordinary quasi-geometrical technique for Fraunhofer diffraction calculations on absolutely absorbing three-dimensional (3-D) bodies of constant thickness is investigated. It is shown that such an application can lead to results that are inadequate for finding the physical diffraction pattern of 3-D bodies. A modified version of the technique is suggested that, to a greater degree, takes into account secondary diffraction and thus permits a more exact presentation of characteristic features of the light diffracted by 3-D bodies. Some examples of this approach applied to the light-diffraction analysis of simple 3-D bodies are given. It is shown experimentally and with calculations that this approach permits description of the diffraction effects of 3-D bodies of the class mentioned in rather simple form and with good accuracy.
© 1981 Optical Society of America
Yu. V. Chugui, V. P. Koronkevitch, B. E. Krivenkov, and S. V. Mikhlyaev, "Quasi-geometrical method for Fraunhofer diffraction calculations for three-dimensional bodies," J. Opt. Soc. Am. 71, 483-489 (1981)