This module explains the difference between conventional and harmonic imaging fields, processing techniques and the impact harmonic processing has on image artifacts.

This illustration is an example of a typical acoustic field. The highest energy is concentrated in the center of the beam, and as a result, the harmonic energy is located in the center of the beam. The wave has to travel some distance to become distorted enough to generate harmonics. It is for this reason there is little harmonic energy in the near field. Higher amplitude sound produces more harmonics.