Fig. 3: Illustration of collimation behavior of the ML.

Collimation-like spatial sound field of ML at 576 kHz (a) and lateral beam width of the emitting transducer compared to the lens in a gelatin tissue phantom (b). The tissue phantom does not cause beam divergence and the beam remains collected along the optical axis. Whereas FWHM of the beam varies by 36% for the transducer, it only varies 4.5% for the length of the beam for the ML (c).