Schlieren Visualization of Anisotropic Dual Slanted Plate Mesoscale Lens Action for Ultrasound

Acoustic and photonic hooks have inspired study of new subwavelength structures to be used as lenses for ultrasound. A new V-shaped plate lens structure exhibits anisotropic focusing behavior in 2D finite element method simulations. The near field is shown in both orientations of the structure, and a frequency sweep was performed to study the response of the lens. Such a lens was built from evenly spaced 200
$\boldsymbol{\mu}\mathbf{m}$
thick brass plates, and the near field was visualized with the schlieren method. The results are compared with the simulation, and anisotropic behavior is confirmed.