From what I understand, ultrasound beams are generated from hundreds of piezo crystals that constructively interfere with one another. When the beam is reflected, it returns to the crystals and the crystal directly above the reflection (the crystal that obtains mechanical vibrations) records the data and assumes the reflection point is right underneath the crystal. Data is then interpreted based on the time it takes for the wave to travel back and forth to the crystal. Please help me understand this phenomenon better. I want to know how these images are created.