A theoretical analysis of acoustic microscopy of spherical cavities

In this paper a theoretical analysis of acoustic microscopy of spherical cavities in solids is presented. The incident field of the acoustic microscope is modeled as a converging acoustic beam of nonplanar wave front. This beam goes through reflection and transmission at the liquid-solid interface. The transmitted beam is scattered by the spherical cavity in solid. The scattered waves come back to the receiver after going through another transmission at the liquid-solid interface. Voltage curves generated by this signal for small as well as large cavities in different materials are analytically synthesized for both horizontal and vertical movements of the microscope lens. It is also shown in this paper how one can obtain the size and location of a cavity from the acoustic microscope generated voltage curves.