The pressure wave forms of Dornier HM-3 at 20 kV along the lithotripter axis at (a) z=−70 mm, (b) z=−45 mm, (c) z=−25 mm, (d) z=−9 mm, (e) z=9 mm, (f) z=25 mm, (g) z=45 mm, and (h) z=70 mm. Left column: Measured results by FOPH. Right column: simulated results of the equivalent reflector model (solid line) and the AC model (dash line). E: the edge wave.