Fractal lenses based on Cantor binary sequences for ultrasound focusing applications

Sergio Pérez-López; José Miguel Fuster; Pilar Candelas; Constanza Rubio

doi:10.1016/j.ultras.2019.105967

Fractal lenses based on Cantor binary sequences for ultrasound focusing applications

Ultrasonics. 2019 Nov:99:105967. doi: 10.1016/j.ultras.2019.105967. Epub 2019 Jul 23.

Authors

Sergio Pérez-López¹, José Miguel Fuster², Pilar Candelas³, Constanza Rubio³

Affiliations

¹ Centro de Tecnologías Físicas, Universitat Politècnica de València, 46022, Spain. Electronic address: serpelo1@teleco.upv.es.
² Departamento de Comunicaciones, Universitat Politècnica de València, 46022, Spain.
³ Centro de Tecnologías Físicas, Universitat Politècnica de València, 46022, Spain.

PMID: 31374429
DOI: 10.1016/j.ultras.2019.105967

Abstract

In this work, we demonstrate the application of Cantor fractal lenses in acoustics. The Cantor Zone Plate (CZP), previously introduced in optics, is designed from a conventional Fresnel Zone Plate (FZP) using a binary sequence governed by the distribution of a generalized Cantor set. The CZP maintains its main focus at the same focal distance than its associated FZP, providing a softer multi-foci focusing profile which is very useful in certain ultrasound therapeutic applications. Experimental measurements are in good agreement with the theoretical model, demonstrating that CZPs are suitable for the ultrasound field.

Keywords: Cantor set; Fractal; Ultrasound focusing; Zone plate.