Modeling Light Diffraction Using the Finite Element COMSOL

J.D. Bamonte
U.S. Naval Academy, Annapolis, MD, USA
Published in 2010

COMSOL is finite element modeling software capable of solving partial differential equations. This capability allows for the modeling of boundary value problems, which is necessary to the study of light and the properties of light propagation. For this study, we are modeling Fraunhofer diffraction of light using a solution of the Helmholtz equation with boundary values appropriate for electromagnetic radiation. The Fraunhofer diffraction pattern is an effect of light propagation that occurs in the far-field. Opposite of Fresnel diffraction, the Fraunhofer pattern is fixed in position and holds a constant shape despite any changes in distance from source to the viewing plane. This boundary value problem serves as the starting point to our study of thermal blooming on a Gaussian beam in COMSOL.