Hi,

I was reading the tutorial page https://support.zemax.com/hc/en-us/articles/1500005578722-Simulating-diffraction-efficiency-of-surface-relief-grating-using-the-RCWA-method.

It mentioned that, for the user defined grating (srg_user_defined_RCWA.dll), we can have multiple sections within one layer. I tried to write multiple sections in a .txt file but the RCWA module will only show one section. For example, if there are three bars with widths a,b,c within one period for one layer, separated by gap g, as shown in the figure below. How should I write the .txt file. 

Thanks.