Set of Reflecting Plates

The pair of acrylic plates makes possible a number of interesting spectral investigations with ultrasound. Due to the low plate thicknesses, the echogram shows multiple reflections. The spectral analysis of individual reflections shows an increasing shifting of the spectrum towards lower frequencies as a result of the frequency-dependent attenuation. The plate thickness is included as a periodic modulation in the spectrum of all reflections. When the plates lie on top of each other, a diffuse echogram is obtained, the spectrum of which also includes diffuse modulations. The individual plate thicknesses can only be determined by a cepstrum analysis. The set includes an acrylic delay line.