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:
Aug. 16, 1983
Filed:
Jan. 23, 1981
Makoto Yamamoto, Yokohama, JP;
Naotaka Miyaji, Yokohama, JP;
Yukinobu Ishigaki, Yokohama, JP;
Kaoru Totsuka, Yokohama, JP;
Victor Company of Japan, Limited, Yokohama, JP;
Abstract
Three microphone units of first order sound pressure gradient unidirectional type are disposed in a casing having front and rear portions at both sides in such a manner that the center axes of the microphone units are aligned on the same axis. Two among the three microphone units are arranged to face the front portion of the casing, and remaining one microphone unit is arranged to face the rear portion of the casing. The output signals of the three microphone units are combined at a variable ratio so that the directivity of the microphone system can widely vary from nondirectivity via first order sound pressure gradient unidirectivity to second order sound pressure gradient unidirectivity. The output signals of two microphone units used for obtaining second order sound pressure gradient unidirectivity may be respectively applied to high pass filters before being combined, and the combined signal is fed to an equalizer. If an equalizer having modified frequency characteristic is employed, such high pass filters may be omitted.