Parabasal thin-element approximation approach for the analysis of microstructured interfaces and freeform surfaces

Area of Science:

• Optics and Photonics
• Computational Electromagnetics

Background:

• The thin-element approximation (TEA) is efficient for analyzing microstructured interfaces like diffractive optical elements.
• Classical TEA is limited to paraxial illumination, restricting its application range.
• Microstructured interfaces are crucial in advanced optical systems.

Purpose of the Study:

• To extend the thin-element approximation (TEA) to include parabasal illumination.
• To develop a new algorithm, the parabasal TEA approach, for analyzing microstructured interfaces under non-paraxial conditions.
• To validate the extended algorithm against rigorous calculations.

Main Methods:

• Development of an extended algorithm incorporating parabasal illumination characteristics.
• Comparison of results from the parabasal TEA approach with rigorous electromagnetic calculations.
• Discussion of the parabasal TEA approach within a broader framework for freeform optics modeling.

Main Results:

• The parabasal TEA approach demonstrates validity for analyzing microstructured interfaces under parabasal illumination.
• The extended algorithm successfully handles light with low divergence and arbitrary propagation directions.
• The study validates the accuracy of the new method through rigorous comparison.

Conclusions:

• The parabasal TEA approach significantly broadens the applicability of TEA methods.
• This advancement enables more accurate modeling of light propagation through complex optical surfaces.
• The method is a valuable tool for designing and analyzing diffractive optics and scattering surfaces.