CN106954163A - A kind of high sensitivity microphone based on quartz-crystal resonator - Google Patents
A kind of high sensitivity microphone based on quartz-crystal resonator Download PDFInfo
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- CN106954163A CN106954163A CN201710237129.8A CN201710237129A CN106954163A CN 106954163 A CN106954163 A CN 106954163A CN 201710237129 A CN201710237129 A CN 201710237129A CN 106954163 A CN106954163 A CN 106954163A
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- 239000013078 crystal Substances 0.000 title claims abstract description 65
- 230000035945 sensitivity Effects 0.000 title claims abstract description 18
- 239000010453 quartz Substances 0.000 claims abstract description 32
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 32
- 230000000694 effects Effects 0.000 claims abstract description 10
- 238000006243 chemical reaction Methods 0.000 claims abstract description 4
- 239000004020 conductor Substances 0.000 claims description 7
- 230000000638 stimulation Effects 0.000 claims description 7
- 230000005611 electricity Effects 0.000 claims description 4
- 238000012545 processing Methods 0.000 claims description 4
- 239000000463 material Substances 0.000 claims description 3
- 230000005284 excitation Effects 0.000 claims description 2
- 230000010358 mechanical oscillation Effects 0.000 claims description 2
- 238000005086 pumping Methods 0.000 claims description 2
- 230000003014 reinforcing effect Effects 0.000 claims description 2
- 230000005540 biological transmission Effects 0.000 abstract description 3
- 230000001133 acceleration Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 230000005236 sound signal Effects 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R17/00—Piezoelectric transducers; Electrostrictive transducers
- H04R17/02—Microphones
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R2217/00—Details of magnetostrictive, piezoelectric, or electrostrictive transducers covered by H04R15/00 or H04R17/00 but not provided for in any of their subgroups
- H04R2217/01—Non-planar magnetostrictive, piezoelectric or electrostrictive benders
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- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
Abstract
The invention discloses a kind of high sensitivity microphone based on quartz-crystal resonator, power-frequency the effect of its foundation quartz-crystal resonator, i.e. when the effect of the oscillator stress (or strain) of quartz-crystal resonator, the resonant frequency of resonator can with the change of power linear change.The present invention core for vibrating diaphragm by sound wave pressure when, vibration can be produced with the size of pressure and the difference of frequency, the vibration is converted into stress on quartz crystal by mechanical structure, so that quartz-crystal resonator produces frequency deviation, so as to complete acoustic-electric conversion, the vibration parameters of diaphragm are can obtain by measuring frequency deviation, the information of acoustic wave of transmission can be further drawn.The characteristics of microphone of the present invention has big sensitivity height, frequency response range, small volume.
Description
Technical field
The invention belongs to microphone field, and in particular to a kind of high sensitivity microphone based on quartz-crystal resonator.
Background technology
In electroacoustic field, traditional microphone is electret capcitor microphone, and its cardinal principle is by foil electret
Electric capacity is formed between vibrating diaphragm or backplane, external sound signal is converted into electric signal.The letter of electret capcitor microphone structure
It is single, it is easy to industrialized production, therefore price is low.But have a larger back cavity in the structure of electret capcitor microphone, so
Thickness is larger, it is impossible to meet the demand of consumer electronics product slimming.In recent years, new silicon microphone, i.e. micro-electro-mechanical systems
(MEMS) microphone of uniting has greater advantage in terms of performance and volume compared to traditional microphones, but MEMS piezoelectricity is transaudient at present
The sensitivity of device is relatively low, hinders its application development.
Quartz-crystal resonator is widely used in the fields such as FREQUENCY CONTROL and communication with its high q-factor, high frequency stability.
In actual applications, the resonant frequency of quartz resonator depends not only on the physical dimension of resonator, while also by such as warm
The influence of the environmental factor such as degree, humidity, power, acceleration and vibration, magnetic field, electric field and radiation.The change of these environmental factors
The change of quartz resonator resonant frequency will be caused to some extent.In these factors, power, acceleration and vibration etc. are to quartz
The influence of resonator resonant frequency is all worked by power-frequency effect.Power-frequency effect be exactly when quartz resonator by
During the effect of applied external force, acceleration and vibration, electrode deformation or the stress caused by other factorses, resonant frequency is produced inclined
The phenomenon of shifting.
The content of the invention
It is an object of the invention to overcome the deficiencies of the prior art and provide a kind of based on the highly sensitive of quartz-crystal resonator
Microphone is spent, using power-frequency characteristic of quartz-crystal resonator, sound wave is carried in the vibration information produced on vibrating diaphragm
Stress is converted on quartz-crystal resonator so that quartz-crystal resonator produces frequency deviation, turned so as to complete acoustic-electric
Change, the vibration parameters of diaphragm are can obtain by measuring frequency deviation, can further draw the information of acoustic wave of transmission.
The purpose of the present invention is achieved through the following technical solutions：It is a kind of based on the highly sensitive of quartz-crystal resonator
Spend microphone, including vibrating diaphragm, mechanical structure, quartz-crystal resonator, vibratory stimulation circuit, data acquisition and procession electricity
Road；
The vibrating diaphragm by sound wave pressure when, can with pressure size and frequency difference and produce vibration；
The mechanical structure is used to the vibration that produces vibrating diaphragm and is converted to power F being loaded into shaking for quartz-crystal resonator
On sub (sensing element) so that quartz-crystal resonator produces frequency deviation, so as to complete acoustic-electric conversion；
During the effect of the oscillator stress (or strain) of the quartz-crystal resonator, its resonant frequency f0Understand the change with power
And linear change；
The vibratory stimulation circuit be multivibrator circuit, can after the power-up output frequency be f square wave；In access
After quartz-crystal resonator, it exports the natural resonance frequency f that square wave frequency is quartz-crystal resonator0；
The frequency collection includes frequency collection circuit and signal processor with data processing circuit, by measuring frequency deviation
Obtain the vibration parameters of vibrating diaphragm；Analyze the relation that sound wave and vibrating diaphragm produce vibration, you can draw sound wave amplitude and
The information such as frequency.
Further, the quartz-crystal resonator is by quartz wafer (i.e. oscillator), electrode and the part group of contact conductor three
Into；Electric excitation signal is added on quartz wafer by contact conductor and electrode, it is produced mechanical oscillation, while can from electrode
To get corresponding electric signal；When the frequency and the intrinsic frequency f of quartz wafer of pumping signal0When consistent, quartz wafer will
Produce resonance.
Further, the quartz material type selecting of making quartz wafer, which should consider, obtains as far as possible big force sensitivity, frequency
Rate working range and optimal frequency-temperature characterisitic, shape and reinforcing direction are cut according to concrete application selection is corresponding.
Further, the mechanical structure includes shell, fixed connection apparatus and external electrode；Mechanical structure is shaped as rectangular
Vibrating diaphragm is fixed in body, two relative sides；Vibrating diaphragm is connected with quartz-crystal resonator by fixed connection apparatus, and
And quartz-crystal resonator is fixedly connected device and is fixedly supported upon in mechanical structure；By the contact conductor of quartz-crystal resonator
Weld together with external electrode and draw shell.
The beneficial effects of the invention are as follows：Power-frequency effect of the microphone of the present invention according to quartz-crystal resonator, that is, work as stone
During the effect of the oscillator stress (or strain) of English crystal resonator, the resonant frequency of resonator can linearly become with the change of power
Change.The present invention core for vibrating diaphragm by sound wave pressure when, can with pressure size and frequency difference and produce
Vibration, stress is converted on quartz crystal by the vibration by mechanical structure so that quartz-crystal resonator produces frequency
Partially, so as to complete acoustic-electric conversion, the vibration parameters of diaphragm is can obtain by measuring frequency deviation, the sound wave of transmission can be further drawn
Information.The characteristics of microphone of the present invention has big sensitivity height, frequency response range, small volume.
Brief description of the drawings
Fig. 1 is the high sensitivity microphone construction schematic diagram based on quartz-crystal resonator；
Fig. 2 is mechanical structure and quartz-crystal resonator connection diagram, and (a) is top view, and (b) is left view, and (c) is
Front view；
Fig. 3 is vibratory stimulation circuit diagram；
In figure, 1- quartz crystals, 2- electrodes, 3- contact conductors, 4- shells, 5- fixed connection apparatus, 6- external electrodes, 7- shakes
Dynamic diaphragm.
Embodiment
Embodiment 1
To make the object, technical solutions and advantages of the present invention clearer, below in conjunction with attached in the embodiment of the present invention
Figure, the technical scheme in the embodiment of the present invention is clearly and completely described.Obviously, the embodiment is the present invention one
Divide embodiment, rather than whole embodiments.Based on embodiments of the invention, those of ordinary skill in the art are not making wound
The other embodiment that the property made is obtained on the premise of working, belongs to protection scope of the present invention.
The present invention provides a kind of high sensitivity microphone based on quartz-crystal resonator.As shown in figure 1, the microphone bag
Include vibrating diaphragm, mechanical structure, quartz-crystal resonator, vibratory stimulation circuit, frequency collection and data processing circuit.
As shown in Fig. 2 the sensitivity in order to improve total system, the material type selecting of quartz crystal 1 should consider acquisition
Big force sensitivity, frequency operating range and optimal frequency-temperature characterisitic as far as possible.In all cut types of quartz crystal,
Only AT cut types(xyl) -30 ° of cut types and BT cut typesWith zero temperature coefficient point, i.e., at certain
On individual temperature value, resonator is zero to the first derivative of temperature, near this temperature value, and frequency variation with temperature is smaller.
And in above-mentioned three kinds of cut types, AT cut types have maximum force sensitivity.Therefore, the quartz crystal 1 that the present embodiment is selected is AT
Cut type.
As shown in Fig. 2 the quartz-crystal resonator vibration mode is thickness shearing mode, its resonant frequency can be represented
For：
In formula (1), tx：The thickness of quartz crystal, n：Overtone order, ρ：Crystalline density, c*：Coefficient of elasticity.
For the quartz-crystal resonator of specific cut type, formula (1) can also be written as：
In formula (2), N0For frequency constant.For AT cut types, N0=1661Hzm.
As shown in Fig. 2 when the quartz crystal 1 is acted on by the radial load F of thickness direction, its resonant frequency will be by original
F0It is changed into f0+ △ f, △ f and F are linear, and this linear relationship is always maintained to F being large enough to produce resonator
Raw mechanical damage.
As shown in Fig. 2 the mechanical structure includes shell 4, fixed connection apparatus 5 and external electrode 6.Mechanical structure is shaped as
Cuboid, its left and right sides fix vibrating diaphragm 7, and remaining is shell 4 sideways.Vibrating diaphragm 7 leads to quartz-crystal resonator
Fixed connection apparatus 5 is crossed to connect, and quartz-crystal resonator is fixedly connected device 5 and is fixedly supported upon in mechanical structure.Will
The contact conductor 3 of quartz-crystal resonator welds together with external electrode 6 and draws shell 4.
As shown in figure 1, the vibrating diaphragm 7 by sound wave pressure when, can with the size and the difference of frequency of pressure
And produce vibration.The vibration is acted on quartz-crystal resonator by the converting to force F of fixed connection apparatus 5, and it is in power-frequency
Resonant frequency will produce change under the influence of characteristic, by f0It is changed into f0+ △ f, △ f and F are linear.
As shown in figure 3, the vibratory stimulation circuit includes phase inverter G, feedback resistance RFAnd coupled capacitor C.Pass through choosing
Take appropriate feedback resistance RFValue, so that it may so that phase inverter G quiescent point is located at the break over region of voltage-transfer characteristic.The electricity
Road is self-maintained circuit, because not stable working condition, multivibrator is also referred to as astable circuit.Specifically,
If multivibrator is in 0 state at the beginning, then it will be transferred to 1 state automatically after 0 state stays for some time, 1
State will be transferred to 0 state automatically again after staying for some time, and so go round and begin again, and export square wave.
As shown in figure 3, quartz crystal has superior frequency-selecting performance.Quartz crystal is introduced into common multivibrator with regard to energy
Constitute the quartz crystal multivibrator with upper frequency stability.Common multivibrator is a kind of square-wave generator,
The square wave that output frequency is f after upper electricity.Theoretical according to Fourier analysis, frequency can resolve into infinite many for f square wave
Individual component sine waves, the frequencies of component sine waves for nf (n=1,2,3 ... ..), if the series resonance frequency of quartz crystal
For f0, then only frequency is f0Component sine waves can by quartz crystal formation positive feedback, and other component sine waves without
Method passes through quartz crystal.Frequency is f0Component sine waves be inverted device and be converted into frequency for f0Square wave.When quartz crystal is humorous
Shake device resonant frequency become turn to f0' when, the square wave frequency of oscillating circuit output, which can also become, turns to f0’。
As shown in figure 1, frequency collection and data processing circuit, including single-chip microcomputer and its peripheral circuit.Frequency measurement is by list
Counter inside piece machine is completed, and count value just can obtain frequency measurement after digital filtering and normalizing computing.According to
Frequency measurement can obtain the vibration parameters of vibrating diaphragm, and analysis magnitudes of acoustic waves and frequency produce the pass of vibration with vibrating diaphragm
System, can from which further follow that the amplitude and frequency information of sound wave, reach transaudient effect.
The content not being described in detail in description of the invention belongs to prior art known to professional and technical personnel in the field.
Claims (4)
1. a kind of high sensitivity microphone based on quartz-crystal resonator, it is characterised in that：Including vibrating diaphragm, machinery knot
Structure, quartz-crystal resonator, vibratory stimulation circuit, data acquisition and procession circuit；
The vibrating diaphragm by sound wave pressure when, can with pressure size and frequency difference and produce vibration；
The vibration that the mechanical structure is used to produce vibrating diaphragm is converted to the oscillator that power F is loaded into quartz-crystal resonator
On (sensing element) so that quartz-crystal resonator produces frequency deviation, so as to complete acoustic-electric conversion；
During the effect of the oscillator stress (or strain) of the quartz-crystal resonator, its resonant frequency f0Meeting line with the change of power
Property change；
The vibratory stimulation circuit be multivibrator circuit, can after the power-up output frequency be f square wave；In access quartz
After crystal resonator, it exports the natural resonance frequency f that square wave frequency is quartz-crystal resonator0；
The frequency collection includes frequency collection circuit and signal processor with data processing circuit, is obtained by measuring frequency deviation
The vibration parameters of vibrating diaphragm；Analyze the relation that sound wave produces vibration with vibrating diaphragm, you can draw the amplitude and frequency of sound wave
Etc. information.
2. a kind of high sensitivity microphone based on quartz-crystal resonator according to claim 1, it is characterised in that：Institute
Quartz-crystal resonator is stated to be made up of quartz wafer (i.e. oscillator), electrode and the part of contact conductor three；Electric excitation signal passes through electricity
Pole lead and electrode are added on quartz wafer, it is produced mechanical oscillation, while can get corresponding electric signal from electrode；
When the frequency and the intrinsic frequency f of quartz wafer of pumping signal0When consistent, quartz wafer will produce resonance.
3. a kind of high sensitivity microphone based on quartz-crystal resonator according to claim 2, it is characterised in that：System
Make the quartz material type selecting of quartz wafer and should consider to obtain big force sensitivity as far as possible, frequency operating range and optimal
Frequency-temperature characterisitic, shape and reinforcing direction are cut according to concrete application selection is corresponding.
4. a kind of high sensitivity microphone based on quartz-crystal resonator according to claim 1, it is characterised in that：Institute
Stating mechanical structure includes shell, fixed connection apparatus and external electrode；Mechanical structure is shaped as cuboid, and two relative sides are consolidated
Determine vibrating diaphragm；Vibrating diaphragm is connected with quartz-crystal resonator by fixed connection apparatus, and quartz-crystal resonator quilt
Fixed connection apparatus is fixedly supported upon in mechanical structure；The contact conductor of quartz-crystal resonator and external electrode are welded together
And draw shell.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201710237129.8A CN106954163A (en) | 2017-04-12 | 2017-04-12 | A kind of high sensitivity microphone based on quartz-crystal resonator |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201710237129.8A CN106954163A (en) | 2017-04-12 | 2017-04-12 | A kind of high sensitivity microphone based on quartz-crystal resonator |
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| CN106954163A true CN106954163A (en) | 2017-07-14 |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109490663A (en) * | 2018-10-26 | 2019-03-19 | 北京无线电计量测试研究所 | A kind of crystal resonator test macro and calibration method |
| CN114441426A (en) * | 2021-12-22 | 2022-05-06 | 中国兵器工业第五九研究所 | Environmental effect monitoring devices and system |
| CN115855300A (en) * | 2023-02-27 | 2023-03-28 | 常州奇军苑传感技术有限公司 | Horizontal length extension mould quartz temperature sensor |
| CN116773455A (en) * | 2023-08-18 | 2023-09-19 | 之江实验室 | Dual resonant sensor device and method |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109490663A (en) * | 2018-10-26 | 2019-03-19 | 北京无线电计量测试研究所 | A kind of crystal resonator test macro and calibration method |
| CN109490663B (en) * | 2018-10-26 | 2021-03-19 | 北京无线电计量测试研究所 | Crystal resonator test system and calibration method |
| CN114441426A (en) * | 2021-12-22 | 2022-05-06 | 中国兵器工业第五九研究所 | Environmental effect monitoring devices and system |
| CN115855300A (en) * | 2023-02-27 | 2023-03-28 | 常州奇军苑传感技术有限公司 | Horizontal length extension mould quartz temperature sensor |
| CN115855300B (en) * | 2023-02-27 | 2023-04-28 | 常州奇军苑传感技术有限公司 | Quartz temperature sensor of horizontal length expansion die |
| CN116773455A (en) * | 2023-08-18 | 2023-09-19 | 之江实验室 | Dual resonant sensor device and method |
| CN116773455B (en) * | 2023-08-18 | 2023-11-21 | 之江实验室 | Dual resonant sensor device and method |
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Application publication date: 20170714 |