Greg Baethge
Ansys Employee

Apologies for this, the content of this post got damaged for some reason. You can't model unpolarized light in FDTD directly. To simulate an unpolarized beam, you need 2 separate simulations, with 2 orthogonal polarizations (typically we use a polarization angle of 0 and 90°). Then you can average incoherently the results.

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