Ansys Learning Forum › Forums › Discuss Simulation › Photonics – Korean › Plane Wave Source 위치 이동 불가능한 버그 › Reply To: Plane Wave Source 위치 이동 불가능한 버그
For plane wave source, in order to prevent from accidently smaller source size than the simulation region (device period in most cases), the software automatically adjusts the plane wave spans to be larger than simulation region. When there is no FDTD added, I believe it has an internal default size, such as adding a certain length to the spans.
In summary, one should avoid to modify the plane wave spans. In a few cases if you really want to use limited plane wave size, please use "diffraction plane wave". Please note that in such case the source will have strong diffraction as the wavefront is limited in size. In theory, the wavefront of the plane wave should not be blocked by any means. Only the periodic-type boundary conditions can allow this, eg, mimic the plane wave as uninterrupted.