Reply To: Far-field planar mode projection

[Guilin Sun]

 

In the settings https://optics.ansys.com/hc/en-us/articles/360034917353-FDE-solver-analysis-Modal-Analysis-Tab  it did not mention what method it is used for plannar projection. It might be the regular farfield projection with scaling distance, which is not accurate for small distance. Consideting its fast calculation, it might not use farfieldexact, which requires raw data in the uniform material: https://optics.ansys.com/hc/en-us/articles/360034914713-Far-field-projections-in-FDTD-overview

So there is a price to pay when you try to simplify the calculation.  The correct method is to use FDTD:

https://optics.ansys.com/hc/en-us/articles/360034914833-Adjusting-the-projection-distance-in-far-field-projections