Fig. 5
From: Self-focusing high-frequency ultrasonic transducers for non-destructive testing applications
(a) Experimental pulse-echo waveform and normalized frequency spectrum; (b) Optical and C-mode image of resolution stainless steel board (d = 100 μm, 200 μm, 300 μm), respectively; (c) Amplitude of resolution board at the red dotted line in (b); (d) Fabricated tungsten wires phantom; (e) Lateral resolution obtained from B-mode imaging of tungsten wire phantom.
