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:
Nov. 24, 1987
Filed:
Nov. 12, 1985
Robert J Martin, Orlando, FL (US);
Claude Sims, Orlando, FL (US);
Sparton Corporation, Jackson, MI (US);
Abstract
An acoustic transducer, especially adapted for hydrophones, is disclosed. The transducer comprises a piezoelectric ceramic disk with a main or signal electrode, a common electrode and a feedback electrode; negative feedback is provided around an associated amplifier and the transducer. The transducer is useful in either a sonic receiver or a sonic transmitter. Various ceramic disk configurations are disclosed and several electrode configurations are disclosed. The negative feedback minimizes the undesired effects of the high Q characteristic of the piezoelectric ceramic transducer. The transducer exhibits improved frequency response characteristics including increased bandwidth and reduced resonance effects, fixed or linear phase shift over a broad range and improved transient response. Also, the effect of normal manufacturing variations upon sensitivity, frequency and phase response is minimized.