Ultrasound: physics and knobology

Nature of Sound Waves

• How far the sound waves can travel depend on
  • how strong the signal is
  • the medium that the waves have to travel though; underwater is greater medium compared to brick wall.

Wave Properties

• Penetration
• Attenuation
• Reflection

Penetration

• Ultrasound waves, depending on amount of energy, will pass through a medium to a certain depth.

Attenuation

• As ultrasound waves travel through medium they continually losing energy to medium that they pass.

Reflection

• The rest of waves' energy after travelling through medium is reflected back toward their source.
• Equals to "echo" of submarine sonar.
• Enable image generation on ultrasound machine.