Bridging Statistical Scattering and Aberration Theory: Ray Deflection Function -- II: Numerical Validation
Netzer Moriya
TL;DR
The paper addresses modeling surface roughness in optical systems by introducing the Ray Deflection Function (RDF), which links statistical scattering (Harvey-Shack) to deterministic aberration analysis through a phase-function representation. It validates the RDF numerically for a parabolic mirror by comparing three models: an ideal baseline, HS-based statistical perturbations, and an RDF-based aberration-term approach, showing near-focal-plane distributions are statistically equivalent. The Aberration Term method demonstrates close agreement with HS in focal-volume characteristics, supporting the claim that roughness can be represented as equivalent deterministic shape changes without sacrificing statistical fidelity. This framework enables tighter integration of surface-roughness effects into conventional optical design workflows, offering computational advantages for large systems and practical relevance to astronomical optics, lithography, and high-power laser applications.
Abstract
This paper presents a comprehensive experimental validation of a recently developed Ray Deflection Function (RDF) approach, which offers a new framework for modeling surface roughness effects in optical systems. Through detailed geometrical ray tracing simulations, we demonstrate that the RDF methodology successfully bridges two traditionally separate domains: statistical scattering models and deterministic aberration analysis. We implement and compare the two approaches for modeling a parabolic mirror with surface imperfections with three cases: (1) an ideal parabolic mirror baseline, (2) the conventional Harvey-Shack (HS) statistical scattering theory applied to ray perturbations, and (3) the newly proposed aberration term method based on the RDF theory. Our results confirm the statistical equivalence between the HS approach and the RDF-based aberration term method, with both producing close near-focal-plane distributions and focal volume characteristics. By establishing this equivalence, we validate that surface roughness effects can be accurately represented as deterministic aberration terms while maintaining fidelity to established statistical scattering models.
