Design concept verification for a transcranial acoustic lens with instantaneous adaptability

Abstract

A lens constructed by optimally arranging point-like scatterers on a lattice was proposed according to the Fresnel lens concept and showed superior performance focusing an incident plane wave on a focal point and suppressing the sound field except in the vicinity of the focal point. In the present study, we investigated the transcranial focusing performance of the scatterer-array lens which is a kind of Fresnel acoustic lens. The arrangement of the scatterers was optimized by minimizing an objective function so that the sound field vanishes within the skull except at the focal point(s) and becomes higher at the focal point(s) than in the surrounding area. It was confirmed that the lens focused the incident plane wave with sufficient intensity and contrast with the surroundings, even transcranially.