How to change the size a Plane Wave Source

- March 5, 2024 at 7:28 pm
  
  Chuan Zhong
  Subscriber
  
  Dear Staff Member at Ansys Lumerical FDTD,
  Can anyone help to change the size of a Plane Wave Source, I found it width of the source is always 2 times of my simulation domain. Just wonder if this number is set by default? How can I make a Plane Wave Source is smaller than a simulation size, thank you.
  Best wishes
  Chuan
- March 6, 2024 at 5:40 pm
  
  Amrita Pati
  Ansys Employee
  
  Hi Chuan,
  The "Bloch/periodic" type of plane wave is used to represent a pure plane wave, as a result the solver has been designed to extend it through the entire simulation span.
  If you want to use a plane-wave of finite-size, you can use the "Diffracting" Type plane wave. The diffracting type plane wave is equivalent to plane waves passing through a rectangular aperture with the same size as the source span. It can also be used with PML boundaries but it will diffract.
  Regards,
  Amrita
- March 6, 2024 at 7:05 pm
  
  Chuan Zhong
  Subscriber
  
  Hi Amrita,
  It helps, thank you so much.
  Best wishes
  Chuan