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. 01, 1983
Filed:
Jan. 16, 1981
Richard F Cahill, El Toro, CA (US);
Eric Udd, Huntington Beach, CA (US);
McDonnell Douglas Corporation, Long Beach, MD (US);
Abstract
A light source is operated near its threshhold and its output is split and sent in opposite direction about a fiber optic coil which is exposed to acoustic energy. The recombined light out of the coil is modulated at acoustic frequency. The modulated light can be fed back to the light source which responds to the modulation with large amplitude variations which are sent to a detector for conversion into an electrical signal representative of the acoustic energy. Alternatively, the light beam may be directed from the fiber coil to the detector directly. The sensors can include components for rejecting noise at frequencies not of interest and a plurality of similar sensors can be formed in an array to obtain directional information or increased sensitivity.