Ultrasound Reflection

• Big surface: The surface must be big compared to the ultrasound wavelength when reflection happens.
• Impedance mismatch: The acoustic impedance on both side of the surface must be different.
• Wavefront pattern: The reflected wave from a spherical wave emitted from a point has the same shape as that emitted from its mirrored counterpart.
• Dependence on angle: For plane wave, the reflected wave has the same angle to the surface as that of incident wave.
• A one-dimension example
  
• Wave reflected by a plane surface
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• wave reflected by a tilt plane surfac
  
• Plane wave reflected by a plane surface
  
• Plane wave reflected by a tilt plane surface