Application ID: 46571
This model simulates a 16-level, first-order, focusing Fresnel lens with 50 µm diameter and 150 µm focal length. In one simulation, the Electromagnetic Waves, Frequency Domain interface computes the electric field in the Fresnel lens and the surrounding air domain extended to the focal plane. In the second simulation, the electric field at the exit plane right above the Fresnel lens is propagated to the focal plane using the Fresnel approximation. Finally, the simulation is performed using the Electromagnetic Waves, Beam Envelopes interface. The electric fields at the focal plane calculated by the three methods are compared. The results are in very good agreement.
Additionally, this model demonstrates the short simulation time for the Electromagnetic Waves, Beam Envelopes interface, as it can perform the simulation with a coarser mesh.
The model also demonstrates how to build and run a model method. The model method automatically rebuilds the complex geometry when a design parameter has changed.
These model files relate to the blog post: How to Implement the Fourier Transformation from Computed Solutions
This application example illustrates applications of this type that would nominally be built using the following products:
however, additional products may be required to completely define and model it. Furthermore, this example may also be defined and modeled using components from the following product combinations:
The combination of COMSOL® products required to model your application depends on several factors and may include boundary conditions, material properties, physics interfaces, and part libraries. Particular functionality may be common to several products. To determine the right combination of products for your modeling needs, review the Specification Chart and make use of a free evaluation license. The COMSOL Sales and Support teams are available for answering any questions you may have regarding this.