Snapshot time t = 140 μs for the radiation pattern of a point force (directed along x₂) generating a Ricker pulse with central frequency 250 kHz and spectral bandwidth 10 kHz, which is located at 12.5 cm from the top and 25 cm from the left and the right edge of a field of 50 cm by 50 cm, applied to three cases. (a) Applied to the “Lens 1”, (b) applied to the “Lens 3”, (c) applied to the “Lens 2”; morphing result (d) between (a) and (b); (e) is (c) transformed in a grayscale image; (f) is (d) transformed in a grayscale image and (g) is the absolute value of the difference between (e) and (f).