How to measure spot size for CMOS sensor?

- August 26, 2021 at 12:30 am
  
  Luxima_Andrew
  Subscriber
  
  Hello,
  I am very new to Lumerical FDTD and optical simulations so please excuse any errors and mistakes. I am trying to measure the spot size for a plane wave source passing through microlens and metal stack for a CMOS image sensor model I imported via a GDSII file. Currently following along with the CMOS image sensor example files on Lumerical University, however I am having trouble getting the necessary data to measure the spot size on the surface of the silicon. So far I am able to measure and visualize the electric field (please see attached). Also attached is the object tree and the various monitors I have recording. Any help would greatly appreciated.
  E_field.png
- August 31, 2021 at 1:03 am
  
  Kyle
  Ansys Employee
  
  Ansys staff aren't permitted to download files from the ALF, so I can't view the images you attached to your post. Could you please paste them directly into your post?
  What additional data do you need to calculate the spot size? I would think that all you would need to do is measure the E field at the surface of the silicon with a monitor, as you have already done. You could then normalize and plot the E field, and manually determine the spot size by finding where the field reaches the FWHM or 1/e^2 value.