Defining Desired Metalens Functionality

VirtualLab Fusion 2026.1 (Build 2.8) offers two options for defining a radially symmetric wavefront phase profile:

• Even Order Radial Polynomials – Define spherical, aspherical, or freeform phase profiles using polynomial coefficients (r², r⁴, ...). Coefficients can also be imported automatically from a Zemax OpticStudio Binary 2 surface.
• User Defined Formula – Define the phase profile using a mathematical expression in C# via VirtualLab Fusion's snippet technology.

This tutorial explains this first step in detail. The suggested workflow:

1. Configure an optical setup with a light source, the metalens component, and a detector
2. Define the wavefront phase profile using one of the two methods
3. Verify the optical function using ray tracing

Both methods support parameter optimization – you can automatically adjust coefficients to meet your design goals before continuing with the generation of the surrogate model.

At the end you find two examples with downloadable files that use the User Defined Formula.

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