How to bulid caculate FDTD mode for axially symmertric DOE?

I am a fresh user with FDTD. My job is to simulate DOE propeties with FDTD.
Now I have written some code in matlab refer to bor-fdtd.

but i have some puzzeled about how to introduce incident plane wave into the system and how to build the doe solid in the simulation space.

Is there anyone who can offer me similar matlab code?

thanks.

hi can you share a copy of your code in matlab? i doing the same thing. maybe we could help each other.