These effects can be modelled using the Huygens–Fresnel principle Huygens postulated that every point on a wavefront acts as a source of spherical secondary wavelets and the sum of these secondary wavelets determines the form of the proceeding wave at any subsequent time, while Fresnel developed an equation using the Huygens wavelets together with the principle of superposition of waves, which models these diffraction effects quite well. When a beam of light is partly blocked by an obstacle, some of the light is scattered around the object, light and dark bands are often seen at the edge of the shadow – this effect is known as diffraction. Redish, Using computers in teaching physics, Physics Today, Vol.42, No.1, pp.34–41, January 1989.Example of far field (Fraunhofer) diffraction for a few aperture shapes. Jorge Frances, Manuel Perez-Molina, Sergio Bleda, Elena Fernandez, Cristian Neipp, and Augusto Belendez, Educational software for interference and optical diffraction analysis in Fresnel and Fraunhofer regions based on MATLAB GUIs and the FDTD method, IEEE Transactions on Education, Vol.55, No.1, pp.118–125, February 2012. Oran Brigham, The Fast Fourier Transform and Its Applications, Avantek Inc., Prentice-Hall, 1988. Joel Franklin, Computational Methods for Physics, Cambridge University Press, 2016.Į. DeVries, A First Course in Computational Physics, Jones Bartlett Learning, 2011. Tao Pang, An Introduction to Computational Physics, Cambridge University Press, 2006. Sharma, Optics Principles and Applications, Academic Press Elsevier, 2006. Goodman, Introduction to Fourier Optics, McGraw-Hill, 1996. Pragati Ashdhir, Jyoti Arya, Chaudhary Eksha Rani, and Anshika, Exploring the fundamentals of fast Fourier transform technique and its elementary applications in physics, European Journal of Physics, Vol.42, No.6, p.065805, Sep 2021. Scilab Enterprises et al., Scilab: Free and Open Source Software for Numerical Computation, Scilab Enterprises, Orsay, France, 3, 2012. Marsh, Diffraction patterns of simple apertures, Journal of the Optical Society of America, Vol.64, No.6, 798, June 1974. II, Optica Acta: International Journal of Optics, Vol.20, No.7, pp.549–563, July 1973. Komrska, Fraunhofer diffraction at apertures in the form of regular polygons. ![]() P B Sunil Kumar and G S Ranganath, Geometrical theory of diffraction, Pramana, Vol.37, No.6, pp.457–488, December 1991. The target group are undergraduate students of physics and engineering sciences. A computational approach has far greater flexibility and scope in exploring different aspects of a given problem compared to a corresponding analytical treatment of the same. The article aims to highlight the importance and ease of using computational methods in problem-solving. The results presented in this article 1 agree fairly well with theoretical predictions and with those reported in the literature. Some apertures with geometrical shapes, such as triangles, trapeziums, hexagons and pentagons, have been analysed in the past. The basic apertures like single slits, double slits, multiple slits, rectangular and circular are generally treated in theory as a part of any wave optics undergraduate course. Subsequently, the discrete Fourier transform technique is used to generate Fraunhofer diffraction patterns due to the simulated planar apertures. The computational technique of discrete convolution is used to simulate planar diffracting apertures of varied geometry. It is one of the basic principles of Fourier Optics that the field distribution in far-field or Fraunhofer diffraction pattern due to a planar diffracting aperture is proportional to the Fourier transform (FT) of field distribution in the aperture plane.
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