Fresnel diffraction from N-apertures: Computer simulation by iterative Fresnel integrals method

The iterative Fresnel integrals method (IFIM) has been applied for the simulation and generation of the complete near-field Fresnel diffraction images created by N-apertures for the first time. The simulation can be performed in any PC using a MATLAB program developed by the authors. Necessary formalism was derived for the general N-slit problem, and a simulation algorithm was devised for this application. An interesting combination of interference effects with Fresnel diffraction was observed in the simulated images. Transition to the expected Fraunhofer diffraction pattern from Fresnel diffraction for N-apertures is also observed in the simulations under the appropriate conditions. Principal maxima of the expected Fraunhofer diffraction were observed at their expected positions, as well as the expected minima and the secondary maxima. The program can serve as a useful tool to study the complex phenomenon of Fresnel diffraction from N-apertures, and in addition, to study the near-field Fresnel diffraction from amplitude diffraction gratings.