A Rho-cee Hydrophone
Abstract
Traditional piezoelectric materials have much higher impedances than water, and so most hydrophones are hard compared to the surrounding water medium. This "hardness" is the cause of internal and external reflections which manifest themselves as resonance and diffraction factor effects, respectively. Even nonvoided polyvinylidene fluoride (PVDF), a piezoelectic polymer, has a characteristic acoustic impedance (pc) about 2.5 times that of water. With the advent of voided PVDF, however, it is possible to match water's impedance as closely as desired. Through the use of pc window material and pc PVDF, we have constructed a pc hydrophone whose response is essentially free of resonance and diffraction factor effects.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 21, 1985
- Accession Number
- ADA630519
Entities
People
- James M. Powers
- John C. Mcgrath
- Mark B. Moffett
Organizations
- Naval Underwater Systems Center