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:
Jan. 13, 2004
Filed:
Nov. 23, 1998
Applicant:
Inventor:
Koji Manabe, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04B 3/00 ; H03G 5/00 ; H04R 2/500 ;
U.S. Cl.
CPC ...
H04B 3/00 ; H03G 5/00 ; H04R 2/500 ;
Abstract
The ultra-directional speaker of the present invention comprises: an audio generator for generating an audio signal; an ultrasonic generator for generating an ultrasonic signal; a frequency modulator for frequency modulating the ultrasonic signal with the audio signal to produce a frequency modulated ultrasonic signal; and an electro-acoustic transducer for transducing the frequency modulated ultrasonic signal into acoustic waves.