Hi Guilin,

Thank you for your reply. I would like to use the expansion monitors to try the angled monitor. I feel it is a little bit challenging for me. In order to describe my question more visually, I have attached an example. 

According to the LumOpt tutorial page (, the basic setup for the output waveguide is horizontal.

In this case, I want to set up the output waveguides with a certain angle so that they can split as early as possible. When I have angled output waveguides, the regular frequency & power monitors cannot work as an input source in the adjoint simulation with a minimum simulation time. Therefore, the frequency & power monitor might not work without a rotation for this inverse design. 

I have attached the files through a Dropbox link and hope you could check them if possible.


Thanks again for your time.