# Multifocal Lens 1

This example is a polarization-independent metalens that focuses light onto two different spots on the xy-plane:

<figure><img src="/files/vXAh4SpcNzr9HMkPAwbh" alt="" width="375"><figcaption><p>Multifocal metalens 1. Lens size is 20 µm and red dots represent focal spots.</p></figcaption></figure>

## Simulation Results

Since the unit cells (shape: circle) are symmetric, the results of Pol 1 and Pol 2 are identical.

<figure><img src="/files/nsfPRiowfCLF4EAYwfYo" alt=""><figcaption><p>Simulation results in SMD PRO.</p></figcaption></figure>

## BUILD Parameters

Below figure shows the BUILD parameters used for this example. To build your own lens, you can use any symmetric unit cells that will be polarization-independent for your polarizations. The key is Phase Error Max. If the value is too small, you may not be able to build the multifocal lens as the condition is too tight for both polarizations (Pol 1 and Pol 2). If too big, then the lens may have a poor performance.

<figure><img src="/files/YsXzLJvxA5hsEiwUVujA" alt=""><figcaption><p>Build parameters and unit cell details in SMD PRO.</p></figcaption></figure>

## GDS

<figure><img src="/files/0vjTLzfcI19LJxpzvUqy" alt="" width="563"><figcaption></figcaption></figure>


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