Wave-optical modeling beyond the thin-element-approximation.

Area of Science:

• Optics and Photonics
• Computational Physics
• Micro-optics

Background:

• Designing micro-optical elements with high index contrasts and large numerical apertures requires advanced simulation techniques.
• Existing beam-propagation methods often fall short in accuracy and speed for these complex optical systems.
• Simulations beyond the thin-element approximation are crucial for realistic analysis.

Purpose of the Study:

• To introduce and evaluate a modified wave-propagation method for micro-optical element simulations.
• To compare its performance against existing beam-propagation methods in terms of accuracy, sampling density, and computational speed.
• To demonstrate its utility in realistic wave-optical simulations beyond the thin-element approximation.

Main Methods:

• Development of a modified wave-propagation method formulation.
• Comparative analysis of the modified wave-propagation method and various beam-propagation methods.
• Assessment of accuracy, sampling density requirements, and computational performance.
• Application of the method to in-line holographic measurements of strongly diffracting objects.

Main Results:

• The modified wave-propagation method is significantly faster and more accurate than beam-propagation methods for micro-optical components.
• It achieves higher accuracy even at lower sampling densities.
• Enables realistic wave-optical simulations beyond the thin-element approximation.

Conclusions:

• The modified wave-propagation method provides a superior approach for simulating micro-optical elements.
• It overcomes limitations of existing methods, enabling more efficient and accurate optical design.
• Successful application in holographic measurements validates its practical utility for retrieving geometric parameters with high accuracy.