학술논문
Design Formulas for Flat Gradient Index Lenses With Planar or Spherical Output Wavefront
Document Type
Periodical
Author
Source
IEEE Transactions on Antennas and Propagation IEEE Trans. Antennas Propagat. Antennas and Propagation, IEEE Transactions on. 72(3):2555-2563 Mar, 2024
Subject
Language
ISSN
0018-926X
1558-2221
1558-2221
Abstract
A semi-analytical method is presented for the design of gradient index (GRIN) flat lenses. Closed-form expressions are derived to define the refractive index distribution of the lens, for several cases: collimating lenses with on-axis feed, collimating lenses with off-axis feed, lenses converting spherical wavefronts with different wavenumbers, lenses changing the focal number of a quasi-optical system, and Fresnel zone lenses. The design equations are validated by ray-tracing simulations in inhomogeneous media, implemented by numerical solution of the Eikonal equation.