Learning Forum

[amora]

Hello,

Can I simulate a design with a source that has a light inclination angle of 20 with angular spread from 18 to 30 please?

[Guilin Sun]

If you can reconstruct the E fields (and H fields if possible), you can use script to import it. Please refer this example: Using an equation to define the spatial field profile of a source in FDTD
You can also use pupil function: Defining a beam using a pupil function this method may be better for you since you know the angular quantities. If the spread is not the same in two orthogonal directions, it is possible to use to different NA values.
Please try and see if it works for you.

[amora]

thanks for your reply. I didn't get the answer and I still need your help to solve this problem. I tried to follow the second link ''Defining a beam using a pupil function'' but I couldn't. Also, our source is a plane wave, not a gaussian source. Another point, the source in the ''pupil_function_beam.fsp'' file is still has one angle. Is it possible to clarify more please?

[Guilin Sun]

I am not sure what do you mean "I didn't get the answer". Do you have the field data E and H? if you have, please follow the 1st link in the previous reply.
If you know the spread angles 18 and 30 deg in the two directions, please follow the 2nd reply. Please read the instruction and test the example files. If you have specific question regarding to the example, please write a new post.

Then you said:" but I couldn't. Also, our source is a plane wave, not a gaussian source."
Could you justify that your plane wave has spreading angle?
I would suggest that you consult your supervisor about this. Maybe you are designing something new but I have no such knowledge about plane wave with spreading angles.
Many customers are innovators and have some breakthrough theories. One of such is the modified Snell's law by Harvard team. Such modification leads to hot research in meta surfaces.

[amora]

Thank you for your reply.

In my problem. I have different plane waves. Each plane wave has a different incident angle (sorry if I didn't clarify that from the beginning). Is it possible to simulate something like that using Lumerical please? I haven't seen this kind of problems (I might be wrong), that's why I am asking about it's possibility, thanks.

[Guilin Sun]

for plane wave, simulation cannot have more than one incidence angle, as the Bloch BCs work only for one given angle.
What you can do is to simulate different plane incidence at a time, and then combine the result coherent.
However, you will need to think over their initial phases and locations, as they may induce different interference. We do not have such examples so please do some tests and think over how to get the final results you want. DFT Monitors can record E and H.

[amora]

Thank you for your reply

[amora]

Thanks for your answer