Numerical Simulation of Diffraction Patterns with Different Illumination Laser Wavelength

In this study, a computer simulation program generating Fresnel diffraction patterns from the apertures by using the different illumination wavelength sources has been studied. Changing the aperture-screen distance and the illumination wavelength provides a clear transition of diffraction patterns from the Fresnel to the Fraunhofer region. The diffraction patterns obtained by the Fresnel integral method have been compared with those simulated by the Fraunhofer calculation. There is a good agreement between the results. Certain conditions have been investigated that Fresnel diffraction patterns approach the Fraunhofer diffraction patterns. The simulations have been performed using a personal computer with Matlab software.