The reflected light is recorded in the near field slightly above the surface directly from the FDTD simulation. A beam propagating downward at an angle reflects off the surface and bump. Videos from these courses are also directly available from Scripting - List of videos. In Lumerical FDTD, you can indeed use scripting to create a complex geometry like a distributed Bragg reflector (DBR). The example below shows how the far field projection can be used to see the angular distribution of reflected light from a small surface feature. You can also take the introductory Scripting courses in the AIC to learn more. Script commands can be entered directly into the script prompt, be run from a saved script file (.lsf), or used within some simulation objects. Script commands such as '?' and '+' are at the end (see Misc). Lumerical's scripting language allows you to automate tasks and analysis such as manipulating simulation objects, launching simulations and analyzing results.
