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Double-layer geodesic and gradient-index lenses.

ABSTRACT: A double-layer lens consists of a first gradient-index/geodesic profile in an upper waveguide, partially surrounded by a mirror that reflects the wave into a lower guide where there is a second profile. Here, we derive a new family of rotational-symmetric inhomogeneous index profiles and equivalent geodesic lens shapes by solving an inverse problem of pre-specified focal points. We find an equivalence where single-layer lenses have a different functionality as double-layer lenses with the same profiles. As an example, we propose, manufacture, and experimentally validate a practical implementation of a geodesic double-layer lens that is engineered for a low-profile antenna with a compact footprint in the millimeter wave band. Its unique double-layer configuration allows for two-dimensional beam scanning using the same footprint as an extension of the presented design. These lenses may find applications in future wireless communication systems and sensing instruments in microwave, sub-terahertz, and optical domains.

SUBMITTER: Chen Q

PROVIDER: S-EPMC9054803 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Double-layer geodesic and gradient-index lenses.

Chen Qiao Q Horsley Simon A R SAR Fonseca Nelson J G NJG Tyc Tomáš T Quevedo-Teruel Oscar O

Nature communications 20220429 1

A double-layer lens consists of a first gradient-index/geodesic profile in an upper waveguide, partially surrounded by a mirror that reflects the wave into a lower guide where there is a second profile. Here, we derive a new family of rotational-symmetric inhomogeneous index profiles and equivalent geodesic lens shapes by solving an inverse problem of pre-specified focal points. We find an equivalence where single-layer lenses have a different functionality as double-layer lenses with the same p ...[more]

PMID: 35487907

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