Sensitivity

Figure 4 (right) Comparisons of optical fibre hydrophone output (top) with that of a 0.075mm PVDF needle hydrophone (bottom) in response to a ‘shocked’ 1MHz toneburst. Insets show expanded timescale. Table 1 below shows comparison of detection sensitivities of PVDF hydrophones with optical fibre hydrophone [4].

Table 1 Noise-equivalent-pressures (NEP) of optical fibre, PVDF membrane and needle hydrophones (no signal averaging used).