Learning Forum

[ehsanul.karim]

I have been following the example Large-Scale Metalens – Ray Propagation – Ansys Optics. However, I have been unable to find a method for calculating the efficiency of the metalens in Zemax. For example, I was able to replicate the focal length and FWHM of the article "Diffraction-limited high-efficiency extreme ultraviolet metalens at 13.5 nm wavelength based on nanohole array in molybdenum membrane" in Zemax, but could not calculate the efficiency, which is defined as the ratio of the optical power in the
focal spot area [circle of diameter 2 × FWHM spanning the center of the focal spot] to the incident optical power. I tried following the article How to model multi-mode fiber coupling – Knowledgebase but the calculated efficiency in Zemax is quite small compared to the original paper. I would appreciate any suggestions or references regarding how to perform these calculations.  

[Christophe Weisse]

Hello, thanks for your message.
For the Large Scale Metalens article, you need to generate .h5 files with a compatible version of Lumerical. Did you go through that process ?
This other article: Eye tracking optical system with a metalens – Ansys Optics has .h5 files packaged with the sample files, it might be easier to discuss this example as it is easier to have a common ground.
You can then use different options to assess the efficiency of the metalens surface, for instance with the Polarization -> Transmission analysis that will provide you the transmission for the total system, and for every surface.
To answer your question about the article, I'd most likely need to have more details about your process and details of the setup.
Opening a support ticket is then quite likely a better option. You'd need to use the Ansys Customer Support Space (ACSS)​ to do so.