CN108495246A - A kind of point sound source sound-producing device and vocal technique - Google Patents
A kind of point sound source sound-producing device and vocal technique Download PDFInfo
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- CN108495246A CN108495246A CN201810402573.5A CN201810402573A CN108495246A CN 108495246 A CN108495246 A CN 108495246A CN 201810402573 A CN201810402573 A CN 201810402573A CN 108495246 A CN108495246 A CN 108495246A
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- laser
- sound source
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- point sound
- pulse laser
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R23/00—Transducers other than those covered by groups H04R9/00 - H04R21/00
- H04R23/008—Transducers other than those covered by groups H04R9/00 - H04R21/00 using optical signals for detecting or generating sound
Abstract
The invention discloses a kind of point sound source sound-producing device and vocal techniques, including laser generator, set on the pulse laser head of the laser emitting mouth of laser generator, laser focusing lens in the light path of the pulse laser projected positioned at pulse laser head, the hot spot of air can be punctured by being formed by focusing pulse laser, the light intensity of hot spot is more than the Intensity threshold of plasma production, the plasma small explosion with rapid expanding characteristic is generated while air is breakdown, the plasma of expansion generates a pressure pulse with short and high peak value, the frequency of the pressure pulse can be more than 100kHz, near breakdown point, the pressure pulse is as non-linear supersonic speed shock motion, the spread speed of shock wave is determined by the energy discharged when breakdown air；For the pulsed laser energy of mJ energy ranges, which decays to rapidly sound wave, and to obtain the point sound source for having enough acoustic pressures, having space omnidirectional, which is repeatable.
Description
Technical field
The present invention relates to a kind of point sound source sound-producing device and vocal techniques.
Background technology
It is usually uncommon when measuring with acoustical testings such as the point sound source of microphone array positioning the reverberation time for carrying out reverberation chamber
It hopes and obtains ideal sound system impulse response.But ideal sound system impulse response is only when sound source and receiving sensor have
It could be realized when having dotted and functional response.For receiving sensor, has dotted functional response and be characterized in being easier
It realizes, but point sound source truly is but difficult to obtain.
In practical applications, point sound source usually by the size of ignoring sound source and assumes that sound source has enough omnidirectionals
Come approximate.But in fact, most of signal sources and not having enough omnidirectionals, therefore the impulse response of system will produce
Inaccurate estimation.For example, spherical loudspeaker or point sound source loud speaker（As patent CN201710336415,
CN201520459044, CN200920133673 etc.）It is typically considered dotted, but they are with directive property in high band
, and also there is sizable size.Although the electric spark very little being frequently used in testing, their not reproducible spies
It levies while there are Directed radiation modes.There is presently no a kind of space non-directives really can be used for acoustic measurement and calibration
And physical size is minimum be approximately spatial point point sound source vocal technique and sound-producing device.
Invention content
The first purpose of the invention is to provide a kind of point sound source sound-producing device, it can obtain that there is enough acoustic pressures, have
Space omnidirectional, repeatable point sound source.
In order to achieve the above objectives, the technical solution adopted by the present invention is：
A kind of point sound source sound-producing device, including laser generator, set on the laser generator laser emitting mouth pulse swash
Shaven head, the laser focusing lens in the light path for the pulse laser that the pulse laser head projects, the laser focusing lens,
For focusing the pulse laser to generate the hot spot for puncturing air, the light intensity of the hot spot is more than plasma production
Intensity threshold, point sound source are located at the hot spot.
Preferably, the point sound source sound-producing device further includes the laser line reflection in the light path of the pulse laser
Mirror, the laser line speculum, is adjusted for the light path to the pulse laser.
Preferably, the wavelength 1064/532nm of the pulse laser, pulse width 4-8ns, pulsed laser energy 300-
1000mJ/ times, repetition rate 20-100Hz.
Preferably, the focal length 70-120mm of the laser focusing lens.
Preferably, the beam radius 5-10mm of the pulse laser, laser beam divergent angle 4mrad, the hot spot are straight
Diameter is less than 2500nm.
Second object of the present invention is to provide a kind of point sound source vocal technique, can obtain having enough acoustic pressures, have
Space omnidirectional, repeatable point sound source.
In order to achieve the above objectives, the technical solution adopted by the present invention is：
A kind of point sound source vocal technique, by laser that laser generator is sent out by obtaining pulse laser after pulse laser head；It will
The pulse laser is more than plasma by obtaining to puncture the hot spot of air, the light intensity of the hot spot after laser focusing lens
The Intensity threshold of body production, generates point sound source at hot spot.
Preferably, the light path of the pulse laser is adjusted in setting laser line speculum.
Preferably, the parameter wavelength 1064/532nm of the pulse laser, pulse width 4-8ns, pulsed laser energy
300-1000mJ/ times, repetition rate 20-100Hz.
Preferably, the focal length 70-120mm of the laser focusing lens.
Preferably, the beam diameter 5-10mm of the pulse laser, laser beam divergent angle 4mrad, the hot spot are straight
Diameter is less than 2500nm.
Due to the application of the above technical scheme, the present invention has following advantages compared with prior art：A kind of point of the present invention
Sound source sound-producing device and vocal technique, form the hot spot that can puncture air by focusing pulse laser, and the light intensity of hot spot is more than
The Intensity threshold of plasma production, generates the plasma small explosion with rapid expanding characteristic while air is breakdown,
The plasma of expansion generates a pressure pulse with short and high peak value, and the frequency of the pressure pulse can be more than
100kHz, near breakdown point, the pressure pulse is as non-linear supersonic speed shock motion, and the spread speed of shock wave is by hitting
The energy discharged when air is worn to determine；For the pulsed laser energy of mJ energy ranges, which decays to rapidly sound wave, with
The point sound source that there is enough acoustic pressures, have space omnidirectional is obtained, which is repeatable.
Description of the drawings
Attached drawing 1 is the structural schematic diagram of apparatus of the present invention；
Attached drawing 2 is to use spherical loudspeaker sound source respectively indoors（Upper figure）With laser breakdown air sound source of the present invention（Figure below）
When, use the collected acoustical signal of microphone.
Wherein：1, laser generator；2, pulse laser head；3, laser line speculum；4, laser focusing lens；5, point sound
Source.
Specific implementation mode
The technical solution of the present invention will be further described below with reference to the accompanying drawings.
It is shown in Figure 1, a kind of above-mentioned point sound source sound-producing device, including laser generator 1, set on laser generator 1
The pulse laser head 2 of laser emitting mouth.In the present embodiment, which can be Nd.YAG yag crystals
Laser；The pulse laser head 2 is for obtaining pulse laser, the wavelength 1064nm of the pulse laser, pulse width 6ns, laser
Pulse energy 420mJ/ times, repetition rate 20Hz.
The point sound source sound-producing device further includes the laser line being located in the light path for the pulse laser that pulse laser head 2 projects
Speculum 3, pulse laser after reflection light path on laser focusing lens 4.The laser line speculum 3 is for bearing
High intensity laser beam light beam, with reflected impulse laser, by adjusting the angle of laser line speculum 3 with the light path to pulse laser
It is adjusted, realizes the spatial deflection of pulsed laser beam；The laser focusing lens 4 are used for for focusing pulse laser with generating
Puncture the hot spot of air.The light intensity of the hot spot is more than the Intensity threshold of plasma production, and point sound source 5 is located at the hot spot.It is logical
The position for moving pulse laser head 2 and laser focusing lens 4 is crossed, the position of scanning laser spark in space can be adjusted, i.e.,
Adjust the position of point sound source 5 in space.
Laser breakdown air sound source is considered the source of a massless, and itself does not generate sound reflecting, this meaning
The source of the point sound source 5 influences minimum.However, focusing the optical device needed for laser beam（Laser focusing lens 4）There may be
Sound reflecting, this can be minimized by using the laser focusing lens 4 with longer focal length, in the present embodiment, described to swash
The focal length 75mm of light condenser lens 4.Or can by before focusing expanded light beam increase focal length, to reduce focal spot size,
In the present embodiment, the beam diameter 6mm of the pulse laser, laser beam divergent angle 4mrad, spot diameter are less than
2500nm.The broadband of laser breakdown air sound source and point-shaped character provide the high time for the phase delay in adjustment Wave beam forming
Resolution ratio, this is particularly suitable for the smaller high-frequency domain of wavelength and temporal resolution.
Laser breakdown air sound source can be positioned arbitrarily, such as in small space（Such as in a tiny pipeline）Or
At object edge.
The parameter of pulse laser（Wavelength, pulse duration, pulse energy and focal length）And the impurity in air can shadow
Air breakdown process is rung, to influence the stability of acoustic characteristic and spark source.Since laser breakdown air point source of sound is half
It generates in the air so that physical constraint is not present in the space configuration of point sound source 5.It can be formed using a few set point sound source sound-producing devices
Laser breakdown air acoustic source array, the array can be adjusted by the focus of mobile pulse laser focusing, and array has can be with
The arbitrary size and shape of customization, to meet different testing requirements.
Laser breakdown air sound source is a kind of explosion point sound source 5, and the duration of pressure pulse is short, is carrying out indoor sound source
It when analysis, even if the distance of other sound reflectors is short, approaches in time, the sound reflecting of these reflectors can also obviously divide
From.Dotted line in Fig. 2 is to use spherical loudspeaker sound source indoors respectively（Upper figure）With laser breakdown air sound source（Figure below）
When, use the collected acoustical signal of microphone.Wherein, ordinate is normalization amplitude, and abscissa is the time, and a indicates direct sound wave,
B indicates that ceiling reflection, c indicate that floor reflection, d indicate laser reflection.
After carrying out deconvolution operation to measuring signal, the solid line in Fig. 2 is obtained as a result, can be more clearly by deconvolution
Obtain pulse acoustic response.
When comparing the test results of two kinds of sound sources and can be seen that using laser breakdown air sound source, in addition to direct sound wave,
The reflection occurred at indoor ceiling and floor separates in which can be apparent from.But using spherical loudspeaker pulse sound source
When, the sound reflecting occurred at ceiling indoors and floor mixes in the response of microphone, even with warp
Product method can not be also clearly separated.
When using laser breakdown air sound source, the sound reflecting signal of laser can be collected by microphone, while
Demonstrate the massless of laser breakdown air sound source.When using spherical loudspeaker, due to the sound shadow of spherical loudspeaker generation
The sound reflecting of laser is blocked, therefore it is to be not present to acquire the signal in the response of microphone.Prove laser breakdown air-borne sound
Source has the characteristic close to ideal point source, therefore can accurately measure the impulse response of sound system.
Above-mentioned a kind of point sound source vocal technique, by laser that laser generator 1 is sent out by obtaining arteries and veins after pulse laser head 2
Impulse light；Again by pulse laser by obtaining to puncture the hot spot of air after laser focusing lens 4, the light intensity of hot spot is more than etc.
The Intensity threshold of gas ions production, generates point sound source 5 at hot spot.The pulsed laser energy that pulse laser is arranged is more than 400mJ/
Secondary, peak power reaches 60 megawatts or more so that air is breakdown while generating has the plasma of rapid expanding characteristic small
The plasma of explosion, expansion generates a pressure pulse with short and high peak value, and frequency is more than 100kHz.In air
Near breakdown point, pressure pulse is discharged as non-linear supersonic speed shock motion when the spread speed of shock wave is by puncturing
Energy determines.For the pulsed laser energy of mJ energy ranges, shock wave decays to rapidly sound wave, therefore at breakdown point（I.e.
At hot spot）Generate point sound source 5.The point sound source 5 scale indoors（1 meter of ＞）When interior progress acoustical testing, the increase of initial velocity
It is undetectable.
The light path of pulse laser can also be adjusted by the way that laser line speculum 3 is arranged, realize pulsed laser light
The spatial deflection of beam.
Nonlinear propagation effects additionally can be minimized by the amplitude of pressure pulse caused by reduction.Amplitude is
Accumulate the function of energy, as long as beyond the intensity threshold for generating breakdown air.It can be by changing laser pulse energy
Amount, pulse duration and focus on light beam size adjust the energy.
The above embodiments merely illustrate the technical concept and features of the present invention, and its object is to allow person skilled in the art
Scholar can understand present disclosure and be implemented, and it is not intended to limit the scope of the present invention, all according to the present invention
Equivalent change or modification made by Spirit Essence should all cover within the scope of the present invention.
Claims (10)
1. a kind of point sound source sound-producing device, it is characterised in that：Go out including laser generator, set on the laser of the laser generator
The pulse laser head of loophole, the laser focusing lens in the light path for the pulse laser that the pulse laser head projects, it is described
Laser focusing lens, for focusing the pulse laser to generate the hot spot for puncturing air, the light intensity of the hot spot is more than
The Intensity threshold of plasma production, point sound source are located at the hot spot.
2. a kind of point sound source sound-producing device according to claim 1, it is characterised in that：The point sound source sound-producing device also wraps
Include the laser line speculum in the light path of the pulse laser, the laser line speculum, for the pulse
The light path of laser is adjusted.
3. a kind of point sound source sound-producing device according to claim 1, it is characterised in that：The wavelength of the pulse laser is
1064/532nm, pulse width 4-8ns, pulsed laser energy 300-1000mJ/ times, repetition rate 20-100Hz.
4. a kind of point sound source sound-producing device according to claim 1, it is characterised in that：The focal length of the laser focusing lens
For 70-120mm.
5. a kind of point sound source sound-producing device according to claim 1, it is characterised in that：The beam radius of the pulse laser
For 5-10mm, laser beam divergent angle 4mrad, the spot diameter is less than 2500nm.
6. a kind of point sound source vocal technique, it is characterised in that：The laser that laser generator is sent out after pulse laser head by obtaining
To pulse laser；By the pulse laser by obtaining to puncture the hot spot of air after laser focusing lens, the hot spot
Light intensity is more than the Intensity threshold of plasma production, and point sound source is generated at hot spot.
7. a kind of point sound source vocal technique according to claim 6, it is characterised in that：Laser line speculum is set to institute
The light path for stating pulse laser is adjusted.
8. a kind of point sound source vocal technique according to claim 6, it is characterised in that：The wavelength of the pulse laser is
1064/532nm, pulse width 4-8ns, pulsed laser energy 300-1000mJ/ times, repetition rate 20-100Hz.
9. a kind of point sound source vocal technique according to claim 6, it is characterised in that：The focal length of the laser focusing lens
For 70-120mm.
10. a kind of point sound source vocal technique according to claim 6, it is characterised in that：The light beam of the pulse laser half
Diameter is 5-10mm, and laser beam divergent angle 4mrad, the spot diameter is less than 2500nm.
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| CN201810402573.5A CN108495246A (en) | 2018-04-28 | 2018-04-28 | A kind of point sound source sound-producing device and vocal technique |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810402573.5A CN108495246A (en) | 2018-04-28 | 2018-04-28 | A kind of point sound source sound-producing device and vocal technique |
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| CN201810402573.5A Pending CN108495246A (en) | 2018-04-28 | 2018-04-28 | A kind of point sound source sound-producing device and vocal technique |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110058246A (en) * | 2019-05-10 | 2019-07-26 | 苏州静声泰科技有限公司 | A kind of Miniaturized low-frequency underwater acoustic transducer |
| DE102021200293A1 (en) | 2021-01-14 | 2022-07-14 | Karlsruher Institut für Technologie | Device and method for reproducing at least one acoustic signal |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100053725A1 (en) * | 2006-11-09 | 2010-03-04 | Leica Microsystems Cms Gmbh | Acousto-optical component |
| CN104406942A (en) * | 2014-11-17 | 2015-03-11 | 浙江大学 | Multi-mode laser-induced breakdown spectroscopy device |
| CN104852772A (en) * | 2015-04-29 | 2015-08-19 | 桂林电子科技大学 | Laser frequency hopping underwater acoustic-induced digital communication system and laser frequency hopping underwater acoustic-induced digital communication method |
-
2018
- 2018-04-28 CN CN201810402573.5A patent/CN108495246A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100053725A1 (en) * | 2006-11-09 | 2010-03-04 | Leica Microsystems Cms Gmbh | Acousto-optical component |
| CN104406942A (en) * | 2014-11-17 | 2015-03-11 | 浙江大学 | Multi-mode laser-induced breakdown spectroscopy device |
| CN104852772A (en) * | 2015-04-29 | 2015-08-19 | 桂林电子科技大学 | Laser frequency hopping underwater acoustic-induced digital communication system and laser frequency hopping underwater acoustic-induced digital communication method |
Non-Patent Citations (4)
| Title |
|---|
| MICHERLI: "光声效应", 《百度文库》 * |
| Л.M.ЛЯМШEВ等: "激光声源", 《声学技术》 * |
| 冯绍松: "激光发声及其发声的机理", 《声学技术》 * |
| 宋正方: "强激光引起的空气击穿", 《激光技术》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110058246A (en) * | 2019-05-10 | 2019-07-26 | 苏州静声泰科技有限公司 | A kind of Miniaturized low-frequency underwater acoustic transducer |
| DE102021200293A1 (en) | 2021-01-14 | 2022-07-14 | Karlsruher Institut für Technologie | Device and method for reproducing at least one acoustic signal |
| WO2022152789A1 (en) | 2021-01-14 | 2022-07-21 | Karlsruher Institut für Technologie | Device and method for reproducing at least one acoustic signal |
| DE102021200293B4 (en) | 2021-01-14 | 2022-08-11 | Karlsruher Institut für Technologie | Device and method for reproducing at least one acoustic signal |
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Application publication date: 20180904 |
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