Learning Forum

[kielyo]

I've been following the online tutorial for the development of a grating coupler using inverse design: Inverse Design of Grating Coupler (2D) – Ansys Optics I've been through editing everything to suit my design but when it comes to the last step of exporting to GDS, it doesn't seem to work. The GDS created gives the error pictures. I retried using the unchanged example and get the same issue with Klayout. I've tried importing the GDS back through Lumerical, and tried a different GDS software, no luck on either.  Any idea's what's going wrong?  Thanks. 

[anna.wirth-singh]

Hello,

This may due to a known compatibility issue with particular versions of KLayout; which version are you using? There is a known issue with KLayout 0.27, and reverting to KLayout version 0.26 or earlier may resolve the issue. We are working on a new method of exporting GDS files, and I will check with the team about the status of this effort and reply back with an update. I will also check the files in this specific example to see if there is a workaround.

More details about our GDS export is available here: GDSII Export Automation – Ansys Optics

Best,

Anna

[kielyo]

Hi Anna, I tried the older version of klayout and success! Thanks for your help. 

[anna.wirth-singh]

Hi, I am glad the older version of Klayout worked! FYI, the link I shared about GDS export contains an updated script that should work with newer versions of Klayout in most cases. However, the grating coupler example is a particular case that has some known issues and we are working to resolve it. For now, I recommend using the older version of Klayout for your case.