The Diffraction Order Port is a subfeature to the Periodic Port. It is used to capture a give diffraction order associated with the parent port condition.

In 2D models enter the Diffraction order m (an integer value). In 3D models enter the Diffraction order m (an integer value) and the Diffraction order n (an integer value).

The diffraction orders are both positive and negative. Typically, start adding the diffraction orders as pairs of positive and negative pairs of the same order. In the Periodic Port it is described how to evaluate how many are necessary.