| 摘要 |
In some embodiments, apparatus and systems, as well as method and articles, may operate to launch acoustic waves along a first acoustic path length from an acoustic transducer toward an axis of rotation, to impinge on a first front surface of a target substantially fixed with respect to the axis, and to receive a reflection of the acoustic waves from the first front surface at the acoustic transducer. After rotating the acoustic transducer about the axis along a substantially circular path, additional activities may include launching acoustic waves along a second acoustic path length, different from the first acoustic path length, from the acoustic transducer toward the axis to impinge on a second front surface of the target, and receiving a reflection of the acoustic waves from the second front surface at the acoustic transducer. Additional apparatus, systems, and methods are disclosed. |
