PVDF hydrophones

PVDF hydrophones

We offer measurement services with PVDF hydrophones. The sensors use the piezoelectric effect for the pressure/voltage conversion. The polymer Polyvinylidenfluorid (PVDF) becomes piezoelectric when it is mechanically stretched and exposed to a strong electric field. A small piece of piezoelectric PVDF foil is attached and electrically contacted to the tip of the hydrophone. This is the pressure sensitive element of the measuring instrument.
PVDF hydrophones can be used for measurements in the low pressure region up to maximum 10 bar.
Our PVDF hydrophones are calibrated with a calibration sound source in a water basin. The acoustic field of the sound source is controlled by the Fiber Optic Probe Hydrophone FOPH 2000.

PVDF hydrophones

Measurement services with two different types of PVDF hydrophones are possible:

Type s	Diameter of the pressure sensitive area: 1 mm (Higher spatial resolution, lower sensitivity)
Type l	Diameter of the pressure sensitive area: 3 mm (Lower spatial resolution, higher sensitivity)

For the measurement of sound signals with very low pressure amplitude the PVDF hydrophones can be operated with a hydrophone amplifier (amplification: 40 dB or 60 dB).

Summary of the technical data

Hydrophone Type	s	l
Spatial Resolution	1 mm	3 mm
Risetime	typ. 150 ns	typ. 150 ns
Bandwidth	typ. 1 kHz to 3 MHz	typ. 1 kHz to 3 MHz
Single pulse pressure resolution	typ. +/- 5 kPa	typ. +/- 0.7 kPa
Sensitivity	typ. 20 mV/MPa	typ. 150 mV/MPa
Accuracy	+/- 15 %	+/- 15 %
Temperature range	10 °C to 35 °C	10 °C to 35 °C