Devika Padmakumar Nair
Ansys Employee



In the geometry tab, make sure the monitor is centered and set the x span and y span to match the span of the simulation region.

Please see the video to understand more about mode sources:

Optical Sources – Mode Source – Introduction & Applications – Ansys Optics

Optical Sources – Mode Source – Setup & Tips – Ansys Optics


Monitors – Introduction and Common Settings – Ansys Optics

Monitors – Frequency-Domain Field – Results & Applications – Ansys Optics

Monitors – Frequency-Domain Field – Setup & Tips – Ansys Optics

And yes, the monitors should be larger than the waveguide to capture the entire light distribution around the waveguide boundary.

I would also recommend the following course : Ansys Lumerical FDTD – ANSYS Innovation Courses

Thnak you