Diffraction Patterns

Application ID: 117


This example resembles the well-known double-slit interference experiment often demonstrated in schools with water waves or sound. The model mimics the plane-wave excitation with two thin waveguides leading to slits in a screen and computes the diffraction pattern on the opposite side of the screen.

The diffraction pattern is clearly visible. The main effect of discretization is that the numerical wavelength differs from the wavelength lambda and thus results in a systematic shift in the angles. It is possible to correct for this effect by adjusting the value of k in the Helmholtz equation to the element size. Such practices are important when you wish to faithfully model interference effects of monochromatic waves.

This model example illustrates applications of this type that would nominally be built using the following products:

COMSOL Multiphysics®