The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 12, 2002
Filed:
Jul. 13, 2000
Axelle Baroni, Rueil Malmaison, FR;
Claude Beauducel, Henonville, FR;
Georges Constantinou, La Vareene Saint Hilaire, FR;
Institut Francais du Petrole, Rueil-Malmaison Cedex, FR;
Abstract
Very low distortion hydrophone comprising at least one pair of sensitive elements ( and ) of piezoelectric type (for example and not limitatively), associated with at least one of the opposite flexible faces of a housing ( ) formed by assembling cups ( and ) with rigid edges. The opposite faces of one of the discs, ( ), are provided with electrodes over the total surface thereof. On the other hand, at least one of electrodes ( and ) associated with the opposite faces of second disc ( ) only covers one or more portions (an annular strip for example) of each of these faces in an external zone of each cup ( ) more subjected to nonlinear stresses. Electrodes ( and ) of the two sensitive discs ( and ) are interconnected so as to make the difference between the electric signals generated by the two discs in response to the pressures applied, with the effect, experimentally verified, that the distortion resulting from this layout, notably due to a second harmonic ( ), is practically suppressed. The hydrophone can be used for geophysics, detection or locating, etc.