Basic R, T setup

glass slab.fsp (277.0 KB)
First setup with FDTD - a slab of glass, transmission and reflection (next I will texture the glass surface, hence 3D simulation). If I am interpreting the results correctly, the reflection (Power_avg = -3.3e-28) is greater than the transmission (Power_avg = 1.9e-35). Where is/are my error(s)? Thanks.

Daer @paul

You don’t have enough mesh cells along the z-direction (light propagation) and therefore light behavior is not captured properly. This is because your FDTD simulation region is around 90um along x and y direction and only 1.7um along z.

To solve the problem, either reduce the material cross section size and FDTD simulation region, or use an override mesh along the z-direction. You can do this by un-checking override x,y mesh from General tab and checking only override z mesh.