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:
Jul. 06, 1993
Filed:
Feb. 28, 1993
John C Baumhauer, Jr, Indianapolis, IN (US);
Jeffrey P McAteer, Fishers, IN (US);
Frederick A Rosebrock, Greenfield, IN (US);
Richard M Sachs, Middletown, NJ (US);
AT&T Bell Laboratories, Murray Hill, NJ (US);
Abstract
A directional microphone assembly is constructed from a first-order-gradient microphone element enclosed within a housing, molded from an acoustically-opaque, resilient material such as Ethylene-Propylene-Diene-Monomer. The microphone element includes a diaphragm which moves under the influence of sound pressures applied on its opposite surfaces to generate an electrical signal which is proportional to the differential sound pressure. The housing includes a first acoustically-transparent channel for communicating sound pressure from a first opening in the housing to one surface of the diaphragm, and a second acoustically-transparent channel for communicating sound pressure from a second opening in the housing to the other surface of the diaphragm. The housing supports the microphone element and forms a continuous seal around its perimeter so that sound pressure in one channel does not leak into the other. The distance between the openings is relatively large in order to improve the sensitivity and directivity of the microphone. Moreover, the directional microphone assembly is configured to be embedded within, or behind, an exterior surface of sound-input equipment with the openings of the housing located along the exterior surface. The resilient housing structure forms a seal with the sound-input equipment surface.