Numerical and experimental analysis of a metamaterial-based acoustic superlens

For many years, the engineering limitations in a single loudspeaker have offered no solution to the problem of delivering sound only to parts of an audience. Precise control on how sound is delivered to an audience has required multiple loudspeakers, either through their distribution or through DSP. The recent uptake of acoustic metamaterials, however, seem to offer different solutions. Using devices based on acoustic metamaterials, for instance, brings to acoustics design principles that come directly from optics, at a reasonable manufacturing cost. In this work, we design, numerically simulate, and characterise an acoustic converging superlens: a 3D-printed device capable of focusing an incoming plane wave at a distance less than one wavelength. We show how a loudspeaker at a fixed distance from the lens results in an “image” of the source at a distance prescribed by the thin-lens equation. Finally, we propose possible applications of such an acoustic superlens to future audio experiences.