Title:
マイクロホンユニット
Document Type and Number:
Japanese Patent JP5293275
Kind Code:
B2
Abstract:
A microphone unit comprises first and second microphones and a delay element. When sound is input to the first and second microphones, the delay element delays an output signal of the first microphone so as to detect the sound by a difference signal between the output signal of the first microphone and an output signal of the second microphone. The delay element delays the output signal of the first microphone so as to satisfy relation 0.76 ¤ D/r ¤2.0 where D is amount of delay for the output signal of the first microphone while r is distance between the first and second microphones. The relation D/r ¤2.0 can reduce far-field noise, while the relation 0.76 ¤ D/r can increase the detection sensitivity to sound emitted from a null point.
Inventors:
Ryusuke Horibe
Takano Rikuo
Fumi Tanaka
Takeshi Inoda
Takano Rikuo
Fumi Tanaka
Takeshi Inoda
Application Number:
JP2009049921A
Publication Date:
September 18, 2013
Filing Date:
March 03, 2009
Export Citation:
Assignee:
Funai Electric Co., Ltd.
International Classes:
H04R3/00; H04R1/40
Domestic Patent References:
| JP2003032779A | ||||
| JP57007285U | ||||
| JP7135694A | ||||
| JP2007300513A | ||||
| JP2009005071A |
Foreign References:
| WO2008062850A1 |
Attorney, Agent or Firm:
Yasuo Itaya
Katsumi Taguchi
Shinichi Mizuta
Katsumi Taguchi
Shinichi Mizuta
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