Mechanically Reconfigurable GRIN Lens Concept for Focusing and Beamforming Applications

TL;DR

This paper introduces a mechanically reconfigurable GRIN lens using corrugated layers with Chebyshev polynomial profiles, enabling adjustable focusing and beamforming by shifting layers, validated through geometrical optics and simulations.

Contribution

It proposes a novel mechanically adjustable GRIN lens design with a Chebyshev polynomial-based index profile for dynamic focusing and beamforming applications.

Findings

Focal point position is controllable by shifting lens layers.

Geometrical optics results align with numerical simulations, with some discrepancies.

Scalability for infrared wavelengths is discussed.

Abstract

This study presents a prospective concept of a mechanically reconfigurable Gradient Index (GRIN) lens for focusing and beamforming applications. The lens is formed by corrugated layers, each realizing a refractive index profile expressed in a basis of Chebyshev polynomials. The focal point position is controlled by shifting the GRIN lens layers. A geometrical optics-based approach is implemented for the three scenarios of focusing at varying focal distance. The geometrical optics results are validated by numerical simulations, with some discrepancies observed due to modeling approximations and structural granularity. We also discuss scalability of the proposed concept for operation at infrared wavelengths.