Fig. 5: Numerical simulations and experimental illustrations of the unidirectional focusing lens (UFL).
From: Unidirectional focusing for broadband Lamb guided wave based on mode conversion
a Phase profile of the designed UFL, with the solid line representing the theoretical result from the generalized Snell’s law and the symbols indicating that of the unidirectionally-transmitted elastic meta-atoms (UTEM). b Experimental setup for measuring out-of-plane displacements. Inset: The designed UFL consists of asymmetric groove (AG) and symmetric grooves (SGs), and the UFL has a length L = 73 mm and width W = 64 mm. The simulated distributions of the displacement fields w (left panels) and the amplitudes ∣w∣ (right panels) of the UFL in c forward- and d backward-incident cases at 328.5 kHz. The dashed-line boxes mark the measurement areas. The insets show the measured displacement field distributions. e Comparison of simulated (lines) and measured (hollow symbols) displacement field profiles along the white dashed lines I and II in (c) and (d).
