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:
May. 30, 2000
Filed:
Apr. 30, 1997
Applicant:
Inventor:
Owen Jones, Ipswich, GB;
Assignee:
Noise Cancellation Technologies, Inc., Linthicum, MD (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
A61F / ;
U.S. Cl.
CPC ...
381 716 ; 330262 ; 381120 ;
Abstract
An active headset providing for reduction of external noise over a given frequency range by means of a microphone which generates an external noise representative signal processed and fed to a loudspeaker to produce an external noise cancellation signal spectrum, wherein a bridge amplifier circuit is interposed between the microphone and the loudspeaker and the gain of the bridge amplifier for peak amplitude of the noise cancellation signal is user adjustable without substantially reducing the breadth of the given frequency range over which noise reduction is effective.