Subdiffraction focusing with a long focal length using a terahertz-wave super-oscillatory lens.
Opt Lett
; 46(19): 4912-4915, 2021 Oct 01.
Article
em En
| MEDLINE
| ID: mdl-34598232
ABSTRACT
This Letter describes a super-oscillatory lens (SOL), with concentric ring-type metallic slits photolithographically fabricated on a glass substrate, that can function at subterahertz frequencies. The SOL has been investigated both experimentally and theoretically and demonstrates a spatial resolution of 1.5 mm (0.5λ), which is 0.45 times the diffraction limit, with a focal length of 75 mm (25λ) at 100 GHz (λ=3mm). Furthermore, the depth of focus of the lens was measured to be 47 mm, which is 10.8 times larger than that of a conventional lens. This type of SOL, with subdiffraction focusing, is thus highly effective for use in industrial inspections with millimeter and terahertz waves.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Opt Lett
Ano de publicação:
2021
Tipo de documento:
Article