CN105323679A - Microphone device - Google Patents
Microphone device Download PDFInfo
- Publication number
- CN105323679A CN105323679A CN201510381935.3A CN201510381935A CN105323679A CN 105323679 A CN105323679 A CN 105323679A CN 201510381935 A CN201510381935 A CN 201510381935A CN 105323679 A CN105323679 A CN 105323679A
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- Prior art keywords
- microphone
- output
- noise
- microphone apparatus
- control part
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Abstract
The invention relates to a microphone device which is capable of outputting sound signals with less noise under a noise generating environment. The microphone device comprises a first uni-directional microphone (10), a second uni-directional microphone (20), wherein the directional axis of the second microphone (20) is virtually identical with the directional axis of the first microphone (10), and the second microphone (20) and the first microphone (10) are arranged in a front and back sequence along the axis; a noise detection part (30) which is used for detecting noise contained in output signals of the first microphone (10); and a control part (40) which is used for controlling the output of the first microphone (10) and the second microphone (20) based on the detection result of the noise detection part (30).
Description
Technical field
The present invention relates to microphone apparatus.
Background technology
The known compound microphone apparatus being equipped with multiple microphone in 1 microphone case.Compound microphone apparatus is built-in with 2 microphones mostly in 1 microphone case.In compound microphone apparatus, the compound microphone apparatus being built-in with 2 microphones in 1 microphone case is also referred to as dual microphone.
Compound microphone apparatus can both output sound signal from any one multiple microphone.Therefore, even if 1 microphone in multiple microphone cannot use because of fault etc., also the output signal from other microphone can be switched to and use compound microphone apparatus.
In the compound microphone apparatus that the places such as dais use, mostly use the electret condenser microphone of single directivity.Even if electret condenser microphone is when closing on setting by multiple microphone, also can prevent utter long and high-pitched sounds (howling) etc.In addition, electret condenser microphone there is no need for the power supply generating polarizing voltage.
In the compound microphone apparatus of the structure by multiple microphone broad ways arrangement, although the tonequality of multiple microphone is difficult to produce difference, the profile of shell correspondingly can increase with the quantity of carried microphone.
Being arranged in the compound microphone apparatus of the structure of row by multiple single directivity microphone on the sensing axle of compound microphone apparatus, the profile of shell can be reduced.
But single directivity capacitance microphone easily produces by the wind-induced noise of air conditioner etc. (wind noise), gas explosion noise (popnoise) of being caused by the air-flow of the plosive etc. of talker etc., the noise that caused by air-flow.
Carried in the compound microphone apparatus of row along the length direction pointed on axle by single directivity microphone, the microphone being equipped on front (near talker) easily picks up the sound of talker, therefore used as main microphone.But the microphone being equipped on front also easily picks up to the above-mentioned noise caused by air-flow.
Thus, in existing compound microphone apparatus, if the microphone pickup in front is to noise, then cannot the few voice signal of output noise.
In addition, disclose following technology, switch output two kinds of signals, namely the output signal of a microphone in 2 non-directive microphones is exported, or export and the inversion signal of another microphone and the signal (for example, referring to patent documentation 1) that obtains are added to the output signal of a microphone.
In the technology disclosed in patent documentation 1, when the noise of surrounding is low, the inversion signal of another microphone is added to the output signal of a microphone and exports the strong signal of directive property.In addition, in the technology disclosed in patent documentation 1, when the noise height of surrounding, only export the output signal of a microphone.
In the technology disclosed in patent documentation 1, when producing high noise near a microphone, easily pickup is to this noise.Therefore, even if the technology disclosed in patent documentation 1, also cannot the few voice signal of output noise.
Prior art document
Patent documentation
Patent documentation 1: Japanese Unexamined Patent Publication 9-149490 publication
Summary of the invention
The object of the present invention is to provide a kind of microphone apparatus, even if under being in the environment creating noise, also can the few voice signal of output noise.
The invention is characterized in have: the 1st microphone of single directivity; 2nd microphone of single directivity, its sensing axle pointing to axle and the 1st microphone is essentially same direction, and the 2nd microphone and the 1st microphone configure along front and back in the axial direction; Noise measuring portion, it detects noise contained in the output signal of the 1st microphone; And control part, its testing result based on noise measuring portion and control the output of the 1st microphone and the 2nd microphone.
Invention effect
According to the present invention, even if under being in the environment creating noise, also can the few voice signal of output noise.
Accompanying drawing explanation
Fig. 1 is the partial sectional view of the execution mode representing microphone apparatus involved in the present invention.
Fig. 2 is the amplification view of the microphone case of the microphone apparatus of Fig. 1.
Fig. 3 is the curve chart of the directional property of the 1st microphone of the microphone apparatus representing Fig. 1.
Fig. 4 is the curve chart of the directional property of the 2nd microphone of the microphone apparatus representing Fig. 1.
Fig. 5 is the curve chart of the directional frequency characteristic of the 1st microphone of the microphone apparatus representing Fig. 1.
Fig. 6 is the curve chart of the directional frequency characteristic of the 2nd microphone of the microphone apparatus representing Fig. 1.
Fig. 7 is the circuit diagram of the microphone apparatus of Fig. 1.
Fig. 8 is the circuit diagram of other execution mode representing microphone apparatus involved in the present invention.
The explanation of Reference numeral
1 microphone apparatus
2 microphone cases
3 support columns
4 flexible pipes
5 base portion frameworks
6 openings
7 openings
8 tail pipes
9 lids
10 the 1st microphones
11 collection lines
12 circuit substrates
20 the 2nd microphones
21 collection lines
22 circuit substrates
30 low pass filters
40 switch drivers
50 volume drivers
100 microphone apparatus
SW1 switch
SW2 switch
VR digital volume controller
Embodiment
● microphone apparatus (1) ●
Hereinafter, with reference to the accompanying drawings of the execution mode of microphone apparatus involved in the present invention.
Fig. 1 is the partial sectional view of the execution mode representing microphone apparatus involved in the present invention.As the microphone apparatus involved by present embodiment, illustrated for the dual microphone of gooseneck type in Fig. 1.As shown in the drawing, microphone apparatus 1 has the microphone case 2 of storage the 1st microphone 10, the 2nd microphone 20 etc.
In addition, microphone apparatus 1 has: support column 3, and it supports microphone case 2; Flexible pipe 4, it supports support column 3; And base portion framework 5, it has not shown out connector etc. and supporting flexible pipe 4.
Fig. 2 is the amplification view of microphone case 2 part of microphone apparatus 1.As shown in the drawing, microphone case 2 is the cylindrical shape possessing peristome at two ends.Microphone case 2 has internal diameter and the length that can receive the 1st microphone 10 and the 2nd microphone 20 in inside.
Microphone case 2 has the opening 6 for collecting from the sound of outside in the inner peripheral portion corresponding with the collection line 11 of the 1st microphone 10.Microphone case 2 has the opening 7 for collecting from the sound of outside in the inner peripheral portion corresponding with the collection line 21 of the 2nd microphone 20.
At the openend of support column 3 side of microphone case 2, in the mode closing this openend, tail pipe (tailpiece) 8 is installed.In addition, is the openend of opposition side (front) at microphone case 2 with the side being provided with tail pipe 8, is provided with the lid 9 covering this openend.Lid 9 is provided with the opening of the sound for collecting the front from microphone apparatus 1.
1st microphone 10 is with the position making collection line 11 mode be positioned at as described above near opening 6 be accommodated in the forward end of microphone case 2.In addition, the 2nd microphone 20 is with the position by tail pipe 8 making collection line 21 mode be positioned at as described above near opening 7 be accommodated in microphone case 2.1st microphone 10 and the 2nd microphone 20 configure along front and back on the length direction of microphone case 2.
1st microphone 10 and the 2nd microphone 20 are electret condenser microphones of single directivity.As long as the sensing axle of the 1st microphone 10 and the 2nd microphone 20 is essentially same direction, such as, points to axle and can be positioned at coaxially.1st microphone 10 and the 2nd microphone 20 are all with the direction of the direction of the lid 9 of microphone case 2 for sensing axle.That is, microphone apparatus 1 take the direction of the lid 9 of microphone case 2 (front extreme direction) as the direction pointing to axle.
In addition, in microphone apparatus involved in the present invention, sensing axle is essentially unidirectional microphone and can be more than 3.
In microphone apparatus 1, the 1st microphone 10 is configured at the position of the forward end of microphone case 2.In microphone apparatus 1, be provided with the lid 9 with opening in the front of microphone case 2.
Fig. 3 is the curve chart of the directional property of the 1st microphone 10 representing microphone apparatus 1.In addition, Fig. 4 is the curve chart of the directional property of the 2nd microphone 20 representing microphone apparatus 1.According to Fig. 3 and Fig. 4, compared with the 2nd microphone 20 be accommodated in by the position of tail pipe 8, be arranged at the stronger towards the directional property of extreme direction before microphone apparatus 1 of the 1st microphone 10 of the position of the forward end of microphone case 2.
That is, in microphone apparatus 1, the 1st microphone 10 to the 2 microphone 20 more easily obtains the sound being positioned at the talker of front extreme direction.
Fig. 5 is the curve chart of the directional frequency characteristic of the 1st microphone 10 representing microphone apparatus 1.In addition, Fig. 6 is the curve chart of the directional frequency characteristic of the 2nd microphone 20 representing microphone apparatus 1.According to Fig. 5 and Fig. 6, the output level by 0 shown in heavy line degree of the 1st microphone 10 and the 2nd microphone 20 does not almost change, and on the other hand, the output level of 90 degree, 180 degree, 120 degree declines to some extent.
The circuit substrate 12 of the electric loop of formation the 1st microphone 10 is accommodated with in the 1st microphone 10.In addition, the circuit substrate 22 of the electric loop of formation the 2nd microphone 20 is accommodated with at the 2nd microphone 20.
Fig. 7 is the circuit diagram of the microphone apparatus 1 of Fig. 1.As shown in the drawing, in microphone apparatus 1, be provided with low pass filter (lowpassfilter) 30, the voice signal (low range voice signal) of the regulation range in the voice signal that this low pass filter 30 only makes the 1st microphone 10 obtain passes through.
Low pass filter 30 plays a role as the noise measuring portion detecting the acoustic constituents suitable with contained noise in the output signal of the 1st microphone 10.Herein, as mentioned above, because the 1st microphone 10 is in the position near talker, so easily pick up the noise element caused by air-flow to wind noise, gas explosion noise etc.Therefore, low pass filter 30 plays a role as noise measuring transducer.
Switch driver (SWD) 40 is provided with, the low range voice signal that namely this switch driver 40 detects based on the testing result of low pass filter 30 and diverter switch SW1 in microphone apparatus 1.
Switch driver 40 compares the low range sound signal level passed through from low pass filter 30 and prespecified pick-off signal level.Herein, prespecified pick-off signal level is the critical level (threshold value) of the noise element (frequency of such as about 100Hz) that the wind noise, gas explosion noise etc. obtained from the 1st microphone 10 is caused by air-flow, and it is stored in the not shown storage part of switch driver 40.
For the comparative result of the level of pick-off signal and the level of low range voice signal, switch driver 40 judge the microphone of output sound signal to switch in the 1st microphone 10 and the 2nd microphone 20 which.
In addition, microphone apparatus 1 is provided with interrupteur SW 1, this interrupteur SW 1 based on the level of pick-off signal and the level of low range voice signal comparative result and switch from the output of the 1st microphone 10 and the output from the 2nd microphone 20.
Interrupteur SW 1 is equivalent to control part, and it switches from the output signal of the 1st microphone 10 and the output signal from the 2nd microphone 20, only exports the signal from some microphones.
Such as the digital switch that can carry out switch motion of electronic type is used for interrupteur SW 1.Utilize interrupteur SW 1, the output switching to the 1st microphone 10 and the 2nd microphone 20 based on switch driver 40 can be carried out.
Further, microphone apparatus 1 is provided with interrupteur SW 2, this interrupteur SW 2 is for switching the output of the 1st microphone 10 and the output of the 2nd microphone 20 in a manual manner for user.Interrupteur SW 2, for when some in the 1st microphone 10 and the 2nd microphone 20 cannot use because of fault, selects the situation etc. of normally carrying out a microphone of action.
In microphone apparatus 1, detect the result of noise based on low pass filter 30 according to the low range voice signal detected, switched the output of the 1st microphone 10 and the 2nd microphone 20 by interrupteur SW 1.
Therefore, according to microphone apparatus 1, when noise is little, the voice signal of the 1st microphone 10 that can be near from the mouth of distance talker exports the sound of acoustical sound.In addition, according to microphone apparatus 1, when noise is large, the voice signal from the mouth of distance spokesman the 2nd microphone 20 far away can be used to carry out the few sound of output noise.
Especially, microphone apparatus involved according to the present embodiment, even if when producing the noise etc. that wind noise, gas explosion noise etc. cause because of air-flow, also can the few sound of output noise.
● microphone apparatus (2) ●
Next, for other execution mode of microphone apparatus involved in the present invention, the difference with the execution mode illustrated before this is only described.
Fig. 8 is the circuit diagram of other execution mode representing microphone apparatus involved in the present invention.As shown in the drawing, the microphone apparatus 100 involved by present embodiment possesses digital volume controller (comprising the electronic sound volume controller of the semiconductor) VR controlled by volume driver 50.Digital volume controller VR is the parts of the interrupteur SW 2 replacing the microphone apparatus 1 illustrated before this, and this point is different from the microphone apparatus 1 illustrated before this.
From only by the 1st microphone 10 exports till only being exported by the 2nd microphone 20 during, digital volume controller VR can make the steps ground of the ratio of the output of the 1st microphone 10 and the 2nd microphone 20 or non-ly to change stepsly.Namely, digital volume controller VR possesses the function that the output that makes the 1st microphone 10 export the 1st microphone 10 and the 2nd microphone 20 is carried out as follows: only make the 1st microphone 10 export, or make the output of the 1st microphone 10 and the 2nd microphone 20 mix and export, or the 2nd microphone 20 is only made to export.
As mentioned above, digital volume controller VR is controlled by volume driver 50.The output signal of microphone apparatus 100 exports from the terminal being equivalent to variable lead-out terminal of digital volume controller VR.
The parts of the switch driver 40 that volume driver 50 illustrates before being replacement.Volume driver 50 and the low range sound signal level correspondingly control figure volume controller VR exported from low pass filter 30.
Therefore, microphone apparatus 100 can control the ratio of the output of the 1st microphone 10 and the 2nd microphone 20 based on the level of the low range voice signal from the 1st microphone 10.
Microphone apparatus 100 is different from the microphone apparatus 1 illustrated before this, the output of the output of the 1st microphone 10 and the 2nd microphone 20 can be mixed with the ratio corresponding to the value of digital volume controller VR and exports the voice signal of microphone apparatus 100.
● the effect of execution mode ●
As described above, microphone apparatus involved according to the present embodiment, can obtain following effect.
In the microphone apparatus involved by present embodiment, from the voice signal of the 1st microphone, detect noise and control the output of the 1st microphone and the 2nd microphone.Therefore, microphone apparatus involved according to the present embodiment, even if under being in the environment creating noise, also can the few voice signal of output noise.
In addition, microphone apparatus involved according to the present embodiment, even if when producing the noise etc. that wind noise, gas explosion noise etc. are caused by air-flow, also can the few voice signal of output noise.
In addition, microphone apparatus involved according to the present embodiment, can according to the presence or absence of noise, size, and the ratio (mixing ratio of voice signal) of the output of the 1st microphone 10 and the 2nd microphone 20 is adjusted to the few state of noise.
Claims (8)
1. a microphone apparatus, has:
1st microphone of single directivity;
2nd microphone of single directivity, its sensing axle pointing to axle and described 1st microphone is essentially same direction, and the 2nd microphone and described 1st microphone configure along front and back in the axial direction;
Noise measuring portion, it detects noise contained in the output signal of described 1st microphone; And
Control part, its testing result based on described noise measuring portion and control the output of described 1st microphone and described 2nd microphone.
2. microphone apparatus according to claim 1, wherein,
Described control part only exports the output of described 1st microphone, or the output of the output of described 1st microphone and described 2nd microphone mixing is exported.
3. microphone apparatus according to claim 1, wherein,
Described control part only exports any one in the output of described 1st microphone and the output of described 2nd microphone.
4. microphone apparatus according to claim 1, wherein,
Described control part controls the ratio of the output of described 1st microphone and described 2nd microphone based on described testing result.
5. microphone apparatus according to claim 1, wherein,
The noise caused by air-flow contained in the output signal of described 1st microphone is detected in described noise measuring portion.
6. microphone apparatus according to claim 1, wherein,
Described noise measuring portion comprises low pass filter.
7. microphone apparatus according to claim 1, wherein,
Described microphone apparatus has shell, and this shell receives described 1st microphone and described 2nd microphone therein,
Described shell possesses peristome sound being incorporated into described 1st microphone and described 2nd microphone.
8. microphone apparatus according to claim 1, wherein,
The directional property towards front extreme direction of described 1st microphone is stronger than the directional property towards front extreme direction of described 2nd microphone.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2014152506A JP6421313B2 (en) | 2014-07-28 | 2014-07-28 | Microphone device |
| JP2014-152506 | 2014-07-28 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN105323679A true CN105323679A (en) | 2016-02-10 |
Family
ID=55250123
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510381935.3A Pending CN105323679A (en) | 2014-07-28 | 2015-07-02 | Microphone device |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP6421313B2 (en) |
| CN (1) | CN105323679A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2017136580A1 (en) * | 2016-02-04 | 2017-08-10 | Magic Leap, Inc. | Technique for directing audio in augmented reality system |
| US10725729B2 (en) | 2017-02-28 | 2020-07-28 | Magic Leap, Inc. | Virtual and real object recording in mixed reality device |
| US11445305B2 (en) | 2016-02-04 | 2022-09-13 | Magic Leap, Inc. | Technique for directing audio in augmented reality system |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2016181752A1 (en) * | 2015-05-12 | 2016-11-17 | 日本電気株式会社 | Signal processing device, signal processing method, and signal processing program |
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| JPH0338993U (en) * | 1989-08-24 | 1991-04-15 | ||
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| JPH03139097A (en) * | 1989-10-25 | 1991-06-13 | Hitachi Ltd | Sound collecting system for microphone |
| CN1174485A (en) * | 1997-07-25 | 1998-02-25 | 程滋颐 | Low-distortion and low-noise microphone |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| WO2017136580A1 (en) * | 2016-02-04 | 2017-08-10 | Magic Leap, Inc. | Technique for directing audio in augmented reality system |
| CN108604439A (en) * | 2016-02-04 | 2018-09-28 | 奇跃公司 | The technology of directional audio in augmented reality system |
| US10536783B2 (en) | 2016-02-04 | 2020-01-14 | Magic Leap, Inc. | Technique for directing audio in augmented reality system |
| CN108604439B (en) * | 2016-02-04 | 2021-12-28 | 奇跃公司 | Techniques to direct audio in augmented reality systems |
| US11445305B2 (en) | 2016-02-04 | 2022-09-13 | Magic Leap, Inc. | Technique for directing audio in augmented reality system |
| US11812222B2 (en) | 2016-02-04 | 2023-11-07 | Magic Leap, Inc. | Technique for directing audio in augmented reality system |
| US10725729B2 (en) | 2017-02-28 | 2020-07-28 | Magic Leap, Inc. | Virtual and real object recording in mixed reality device |
| US11194543B2 (en) | 2017-02-28 | 2021-12-07 | Magic Leap, Inc. | Virtual and real object recording in mixed reality device |
| US11669298B2 (en) | 2017-02-28 | 2023-06-06 | Magic Leap, Inc. | Virtual and real object recording in mixed reality device |
Also Published As
| Publication number | Publication date |
|---|---|
| JP6421313B2 (en) | 2018-11-14 |
| JP2016032139A (en) | 2016-03-07 |
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Application publication date: 20160210 |
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