Formation of Ultrasonic Signals in Layered Objects with Abrupt Changes in Acoustic Impedance

The formation of ultrasonic responses in the images of layered objects with significant differences in acoustic impedance is considered. It is shown that it may be difficult to interpret ultrasound images due to oscillations of the received signal in such structures. The theoretical model for a signal formation was proposed that takes into account the focus displacement relative to the sample surface; the model was experimentally validated.