Stereo microphone

Patent metadata

Field	Value
Publication number	US-2016286307-A1
Application number	US-201615014121-A
Country	US
Kind code	A1
Filing date	Feb 3, 2016
Priority date	Mar 26, 2015
Publication date	Sep 29, 2016
Grant date	—

Abstract

A stereo microphone includes an omnidirectional microphone unit, a bidirectional side-channel microphone unit arranged to be perpendicular to a direction of a sound collecting axis outside the omnidirectional microphone unit, a right-channel microphone unit arranged to form a predetermined angle with respect to the side-channel microphone unit on a plane including the sound collecting axis outside the omnidirectional microphone unit, and a left-channel microphone unit arranged to forma predetermined angle with respect to the side-channel microphone unit and the right-channel microphone unit on the plane including the sound collecting axis outside the omnidirectional microphone unit.

First claim

What is claimed is:

1 . A stereo microphone comprising:
an omnidirectional microphone unit; a bidirectional side-channel microphone unit arranged to be perpendicular to a direction of a sound collecting axis outside the omnidirectional microphone unit; a bidirectional right-channel microphone unit arranged to forma predetermined angle with respect to the side-channel microphone unit on a plane including the sound collecting axis outside the omnidirectional microphone unit; and a bidirectional left-channel microphone unit arranged to form a predetermined angle with respect to the side-channel microphone unit and the right-channel microphone unit on the plane including the sound collecting axis outside the omnidirectional microphone unit.

2 . The stereo microphone according to claim 1 , wherein
the predetermined angle of the bidirectional right-channel microphone unit with respect to the side-channel microphone unit, and the predetermined angle of the bidirectional left-channel microphone unit with respect to the side-channel microphone unit and the right-channel microphone unit are 120°, a directional axis of the right-channel microphone unit is arranged to form 60° with respect to a directional axis of the side-channel microphone unit on the plane including the sound collecting axis, a directional axis of the left-channel microphone unit is arranged to form 60° with respect to the directional axis of the right-channel microphone unit on the plane including the sound collecting axis, and the directional axis of the left-channel microphone unit is arranged to form 60° with respect to the directional axis of the side-channel microphone unit on the plane including the sound collecting axis.

3 . The stereo microphone according to claim 2 , wherein
a figure formed of lines that connect intersection points where two of the directional axes of the right-channel microphone unit, the left-channel microphone unit, and the side-channel microphone unit intersect with each other, respectively, is an equilateral triangle, and the omnidirectional microphone unit is arranged in a center of the equilateral triangle.

4 . The stereo microphone according to claim 1 , wherein
an output of a right channel is obtained by adding an output of the omnidirectional microphone unit and an output of the right-channel microphone unit, an output of a left channel is obtained by adding the output of the omnidirectional microphone unit and an output of the left-channel microphone unit, and an output of a mid channel is obtained by adding the output of the right channel and the output of the left channel.

5 . The stereo microphone according to claim 4 , wherein
the output of the right channel and the output of the left channel configure a stereo sound collecting method that is an XY method.

6 . The stereo microphone according to claim 4 , wherein
the output of the mid channel and an output of the side-channel microphone unit configure a stereo sound collecting method that is an MS method.

7 . The stereo microphone according to claim 1 , wherein
output levels of the omnidirectional microphone unit, an output level of the right-channel microphone unit, and an output level of the left-channel microphone unit are adjusted to adjusted outputs and the adjusted outputs are added.

8 . The stereo microphone according to claim 1 , wherein the side-channel microphone unit, the right-channel microphone unit, and the left-channel microphone unit are arranged with an equal angle on the plane including the sound collecting axis.

9 . The stereo microphone according to claim 1 , wherein
an output of a right rear channel is obtained by subtracting the output of the left-channel microphone unit from the output of the omnidirectional microphone unit, and an output of a left rear channel is obtained by subtracting the output of the right-channel microphone unit from the output of the omnidirectional microphone unit.

10 . The stereo microphone according to claim 9 , wherein
an output of a right front channel is obtained by adding an output of the omnidirectional microphone unit and an output of the right-channel microphone unit, an output of a left front channel is obtained by adding the output of the omnidirectional microphone unit and an output of the left-channel microphone unit.

11 . The stereo microphone according to claim 1 , wherein
the side-channel microphone unit, the right-channel microphone unit, and the left-channel microphone unit are ribbon microphone units, and acoustic terminals of the omnidirectional microphone unit are arranged to be positioned near middles in a longitudinal direction of diaphragms of the ribbon microphone units.

Assignees

• Akino Hiroshi
• Audio Technica Kk

Inventors

• Akino Hiroshi

Classifications

• H04R5/027

  Spatial or constructional arrangements of microphones, e.g. in dummy heads · CPC title

• H04R9/08

  Microphones · CPC title

• H04R1/406 Primary

  microphones · CPC title

• H04R3/005

  for combining the signals of two or more microphones (specially adapted for hearing aids H04R25/407) · CPC title