CN1620195A - Parametric loudspeaker with electro-acoustical disphragm transducer - Google Patents
Parametric loudspeaker with electro-acoustical disphragm transducer Download PDFInfo
- Publication number
- CN1620195A CN1620195A CN 200410087797 CN200410087797A CN1620195A CN 1620195 A CN1620195 A CN 1620195A CN 200410087797 CN200410087797 CN 200410087797 CN 200410087797 A CN200410087797 A CN 200410087797A CN 1620195 A CN1620195 A CN 1620195A
- Authority
- CN
- China
- Prior art keywords
- film
- barrier film
- emitter
- ultrasonic
- frequency
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000005291 magnetic effect Effects 0.000 claims abstract description 108
- 230000006835 compression Effects 0.000 claims abstract description 5
- 238000007906 compression Methods 0.000 claims abstract description 5
- 230000004888 barrier function Effects 0.000 claims description 122
- 238000000034 method Methods 0.000 claims description 56
- 238000002604 ultrasonography Methods 0.000 claims description 27
- 238000006073 displacement reaction Methods 0.000 claims description 22
- 230000033001 locomotion Effects 0.000 claims description 19
- 230000004044 response Effects 0.000 claims description 19
- 239000000203 mixture Substances 0.000 claims description 16
- 239000002033 PVDF binder Substances 0.000 claims description 14
- 229920002981 polyvinylidene fluoride Polymers 0.000 claims description 14
- 239000012528 membrane Substances 0.000 claims description 10
- 230000005855 radiation Effects 0.000 claims description 10
- 238000005452 bending Methods 0.000 claims description 9
- 230000003993 interaction Effects 0.000 claims description 9
- 230000005236 sound signal Effects 0.000 claims description 9
- 230000000644 propagated effect Effects 0.000 claims description 7
- 230000001902 propagating effect Effects 0.000 claims description 7
- 229920006395 saturated elastomer Polymers 0.000 claims description 7
- 238000013519 translation Methods 0.000 claims description 7
- 238000010276 construction Methods 0.000 claims description 6
- 230000005686 electrostatic field Effects 0.000 claims description 5
- 230000002708 enhancing effect Effects 0.000 claims description 4
- 238000002955 isolation Methods 0.000 claims description 3
- 229920000642 polymer Polymers 0.000 claims description 3
- 208000002925 dental caries Diseases 0.000 claims description 2
- 239000000696 magnetic material Substances 0.000 claims 1
- 238000012986 modification Methods 0.000 claims 1
- 230000004048 modification Effects 0.000 claims 1
- LENZDBCJOHFCAS-UHFFFAOYSA-N tris Chemical compound OCC(N)(CO)CO LENZDBCJOHFCAS-UHFFFAOYSA-N 0.000 claims 1
- 238000004804 winding Methods 0.000 claims 1
- 238000011161 development Methods 0.000 abstract description 7
- 239000010408 film Substances 0.000 description 273
- 230000003068 static effect Effects 0.000 description 29
- 239000006260 foam Substances 0.000 description 27
- 230000035939 shock Effects 0.000 description 20
- 239000000463 material Substances 0.000 description 17
- 230000014509 gene expression Effects 0.000 description 15
- 230000008901 benefit Effects 0.000 description 14
- 230000000875 corresponding effect Effects 0.000 description 10
- 239000000758 substrate Substances 0.000 description 10
- 230000000694 effects Effects 0.000 description 9
- 230000008569 process Effects 0.000 description 9
- 238000006243 chemical reaction Methods 0.000 description 8
- 230000008878 coupling Effects 0.000 description 8
- 238000010168 coupling process Methods 0.000 description 8
- 238000005859 coupling reaction Methods 0.000 description 8
- 210000004379 membrane Anatomy 0.000 description 8
- 238000007493 shaping process Methods 0.000 description 8
- 229920002799 BoPET Polymers 0.000 description 6
- 239000005041 Mylar™ Substances 0.000 description 6
- 230000005540 biological transmission Effects 0.000 description 6
- 229910052751 metal Inorganic materials 0.000 description 6
- 239000002184 metal Substances 0.000 description 6
- 238000012360 testing method Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 230000006872 improvement Effects 0.000 description 5
- NJPPVKZQTLUDBO-UHFFFAOYSA-N novaluron Chemical compound C1=C(Cl)C(OC(F)(F)C(OC(F)(F)F)F)=CC=C1NC(=O)NC(=O)C1=C(F)C=CC=C1F NJPPVKZQTLUDBO-UHFFFAOYSA-N 0.000 description 5
- 239000004033 plastic Substances 0.000 description 5
- 229920003023 plastic Polymers 0.000 description 5
- 238000003825 pressing Methods 0.000 description 5
- 238000011160 research Methods 0.000 description 5
- 230000002411 adverse Effects 0.000 description 4
- 230000006870 function Effects 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- 238000003491 array Methods 0.000 description 3
- 239000012141 concentrate Substances 0.000 description 3
- 229920001577 copolymer Polymers 0.000 description 3
- 230000002950 deficient Effects 0.000 description 3
- 238000013461 design Methods 0.000 description 3
- 239000006185 dispersion Substances 0.000 description 3
- 230000005611 electricity Effects 0.000 description 3
- 238000009413 insulation Methods 0.000 description 3
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 3
- 230000004807 localization Effects 0.000 description 3
- 239000005022 packaging material Substances 0.000 description 3
- 229920003223 poly(pyromellitimide-1,4-diphenyl ether) Polymers 0.000 description 3
- 230000002829 reductive effect Effects 0.000 description 3
- 230000000284 resting effect Effects 0.000 description 3
- 230000035807 sensation Effects 0.000 description 3
- 239000010409 thin film Substances 0.000 description 3
- 238000012546 transfer Methods 0.000 description 3
- 230000009102 absorption Effects 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 210000004883 areola Anatomy 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 239000004020 conductor Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 239000003989 dielectric material Substances 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000005284 excitation Effects 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 238000005187 foaming Methods 0.000 description 2
- 230000005012 migration Effects 0.000 description 2
- 238000013508 migration Methods 0.000 description 2
- 230000000149 penetrating effect Effects 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 238000005728 strengthening Methods 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 208000003443 Unconsciousness Diseases 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 230000001154 acute effect Effects 0.000 description 1
- 239000004411 aluminium Substances 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 238000004873 anchoring Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000003139 buffering effect Effects 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 238000003486 chemical etching Methods 0.000 description 1
- 239000013065 commercial product Substances 0.000 description 1
- 230000002860 competitive effect Effects 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 230000002596 correlated effect Effects 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000005183 dynamical system Methods 0.000 description 1
- 238000005485 electric heating Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000003302 ferromagnetic material Substances 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 229920001821 foam rubber Polymers 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 230000008570 general process Effects 0.000 description 1
- 230000007274 generation of a signal involved in cell-cell signaling Effects 0.000 description 1
- 239000003365 glass fiber Substances 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000008384 membrane barrier Effects 0.000 description 1
- 229910001092 metal group alloy Inorganic materials 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000002991 molded plastic Substances 0.000 description 1
- VIKNJXKGJWUCNN-XGXHKTLJSA-N norethisterone Chemical compound O=C1CC[C@@H]2[C@H]3CC[C@](C)([C@](CC4)(O)C#C)[C@@H]4[C@@H]3CCC2=C1 VIKNJXKGJWUCNN-XGXHKTLJSA-N 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 230000036961 partial effect Effects 0.000 description 1
- 230000021715 photosynthesis, light harvesting Effects 0.000 description 1
- 239000002985 plastic film Substances 0.000 description 1
- 229920006255 plastic film Polymers 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 230000010349 pulsation Effects 0.000 description 1
- 238000012797 qualification Methods 0.000 description 1
- 238000003908 quality control method Methods 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 241000894007 species Species 0.000 description 1
- 230000003019 stabilising effect Effects 0.000 description 1
- 239000003351 stiffener Substances 0.000 description 1
- 238000004347 surface barrier Methods 0.000 description 1
- 229920001187 thermosetting polymer Polymers 0.000 description 1
- 239000011800 void material Substances 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R19/00—Electrostatic transducers
-
- 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
- H04R2217/03—Parametric transducers where sound is generated or captured by the acoustic demodulation of amplitude modulated ultrasonic waves
Abstract
A parametric loudspeaker that directly generates multiple high frequencies to indirectly create lower frequencies through the use of substantially monolithic film transducers that are generally larger than a wavelength of the carrier frequency in diameter or cross section. An alternative configuration may include a movable diaphragm stretched along the core member and displaced a short distance within a strong portion of a magnetic field. At least one, low mass, planar, conductive coil is disposed on the movable diaphragm and includes a first contact and a second contect for enabling current flow through the coil to produce a first magnetic field to attract and repel the diaphragm at a desired frequency for development of a series of compression waves which may be adjusted to include an ultrasonic frequency range.
Description
The application is that denomination of invention is " the parameter loud speaker that has electroacoustic barrier film transducer ", and the applying date is on August 26th, 1999, and application number is dividing an application of 99812680.2 Chinese patent application.
Technical field
The present invention relates to the electrostatic loudspeaker transducer.More particularly, the present invention relates to comprise a stator component and based on the parameter speaker transducer of membranous type barrier film.These transducers comprise a single-stage, the electricity-machine conversion of ultrasonic voltage signal to ultrasonic compressional wave, and the value difference of ultrasonic compressional wave is not corresponding to new sound or infrasound compressional wave frequency.
Background technology
The parameter loud speaker is a kind of for the direct acoustic emission device of the high-frequency ultrasonic represented by carrier frequency with from the sideband frequency that the modulation of carrier frequency generates of emission of a sound signal.These disperse supersonic frequency demodulation in a kind of nonlinear dielectric such as air, the modulation sound signal is regenerated actual audio frequency output.In theory, parameter sound drops on the mutual generation of two supersonic frequencies in air (as nonlinear dielectric) in the audio range by the difference of its value.Ideally, the audio compression ripple of generation is launched in air, and hears as pure sound.Although desirable theory, the sound generating of mixing by sound for practical use has made the sector puzzlement surpass 100 years.
Because the generation of audio frequency output is extended along the length of transonic, produce along ultrasonic beam so increase sound pressure level (SPL), up to exhausting ultrasonic energy.By this way, the output class of parameter loud speaker is similar to the end-fired array of conventional loud speaker.Although some similitudes between parameter loud speaker and conventional speaker system, significant new capability produces, because audio frequency output produces from the high-energy ultrasonic emission indirectly, rather than is produced by awl that moves under audio frequency or barrier film.Some of these special performances are known, as sound to the length of emitting area apart from bunchy effect and localization.Other performance did not also recognize in the past, and had prevented the enforcement of commercial Parametric Loudspeaker System.The disclosure and be set forth on August 26th, 1999 and title is filed an application sequence No.09/384 for the modulator of Parametric Loudspeaker System " be used for handle " time, 084, explore several parts of these performances as a kind of full operation parameter loud speaker.The parameter loud speaker of present invention has the output of gamut audio frequency, has and the equal volume of the conventional audio system of high-quality, definition and fidelity.
The theoretical research of purposes that is generally limited to limited performance and installs a transducer array of the piezoelectric bimorph transducer on a stayed surface concentratedly in the effort of prior art aspect the parameter loudspeaker applications to some.Each bimorph emitter is wired on the signal source discretely.According to this configuration, the business development of parameter product has made industry puzzled.This is mainly due to shortage and the equal effective sound reproduction of other conventional sound systems such as dynamic and electrostatic loudspeaker systems.Even provide the place of the remarkable advantage such as strengthening directivity at the parameter loud speaker, also expensive, actual power that the taste audience is arranged require business success and the quality of difference because do not satisfy, and be always very little.
The parameter loud speaker depends on the Supra-voice sound output of peculiar property and effective coupling of surrounding air.As mentioned above, former theory and commercial product research mainly concentrate on the emitter device of using the piezoelectric bimorph structure that is also referred to as the flexural piezoelectric machine.These devices use the two layers of piezoelectric material of bonded to one another and driven out-of-phase.When one deck extended on length, another layer shrank, and provided output movement in 90 planes of spending for the expansion direction.Although the power of these devices is very big, the actual air displacement is on duty mutually with coupling.Therefore, the successful characteristic of bimorph depends on wherein a second level of the transfer process of the local motion that amplifies bimorph in the air around.This realizes by means of the various air coalignments that comprise board-like and tray type structure, and these structures are more or less the same with the wavelength of frequency-of-interest dimensionally.
In order to develop significant SPL, a plurality of such devices separate along a support or other supporting constructions.For example see from the United States Patent (USP) 4,823,908 of Tanaka etc. and obtain, comprise 500 strings or surpass Fig. 6 of 1400 bimorph unit.Because localization emitter of each expression of these devices can easily become shock wave or saturated to air driven so the present inventor has been found that tight high drive strength in each device front.This phenomenon is destroyed effective demodulation of sound signal, causes the serious distortion of the loss of power output and audio frequency sound component and to other serious adverse effects of the general process of parameter loud speaker operation.In addition, bimorph has poor frequency response and unnecessary subharmonic.
To going up largely, be used for making great efforts to concentrate on the quantity that increases the bimorph emitter at the prior art of the enhancing SPL of bimorph system always.Can provide the ultrasonic output of increase although realized the quantity that increases the bimorph emitter, it only enlarges saturation of the air problem and serious power loss.And the present inventor has been found that the multiple restriction of following, and phase matching error, distortion and bandwidth problem that is caused by the variation from device to device and relevant cost and the complexity of using so many discrete devices are arranged.Really, the phase relation of these discrete devices is such, thereby can not add the amount of only estimating by all devices of summation as total output of a string a plurality of devices.For example, test shows that each can produce the array of one 10 bimorph transducer of the SPL of 120db separately, produces only 125 to 127db concentrated SPL.Particularly, this is anticly less than representing that in theory ten have the 120db 130db that adds up of the device of output separately.As above indication, the present inventor believes, this power loss is produced by phase anomaly and the other defect distinguished in the disclosure.
Another perhaps is directed to another factor that depends on the bimorph device to the researcher, be a kind of emitter should with the sensation of the corresponding size configurations of wavelength of the ultrasonic energy that will launch.This ultrasonic device with other types is consistent, as the static emitter of building with the size of the wavelength that is equal to or greater than interested low-limit frequency.Even when using these devices, still need to use big device counting to realize the output of needs.In fact, All the time for sensation, if wish higher SPL, then must use the emitter of larger amt, drives with the high voltage level.This logic is produced by the traditional design sensation from conventional audion system.Yet these conclusions are not to follow Parametric Loudspeaker System with parallel relation.
The present inventor believes, except that the dissatisfied result in the parametric system that has the bimorph transducer, other traditional views that draw from conventional audion system may mislead the early stage researcher parameter loud speaker field, cause hindering the disappointed result of parameter loud speaker progress.This is shown that by the following fact early stage research makes great efforts to be limited to basically the use of the bimorph transducer that generally is categorized as high power device.As if the hope of the bimorph transducer in parameter loud speaker use may be the natural result of parallel experience in the audio frequency industry, and wherein the strong preference to dynamic loudspeaker (also being characterized as high power device) is better than electrostatic loudspeaker.In other words, magnetic drives the popularity and general reception the (being similar to double piezoelectric crystal chip driver and additional Air Coupling awl in itself) of awl, seems the development idea in the parameter field to be guided into the preference bimorph and away from the low output projectile configuration such as the film emitter.
For example, about percent 99 the audion system of selling in the world drops in the kind of dynamic loudspeaker, by be mechanical coupling to one on the awl magnetic drive unit or similarly acoustic driver show.Dynamic loudspeaker is based on two conceptual operations.First relates to electricity-machine process that a voltage signal audio frequency output converts mechanical movement to.This is realized by the magnetic drive unit such as a kind of magnet and coil combination.Second notion is accompanied by first, and wherein mechanical movement combines with a sound coupling device, as combining with the motion of the awl of the displacement that is used for compressional wave.This is called a two-stage loud speaker conceptive.
Such dynamic loudspeaker is called high power device, because they can produce high volume level according to the intensity of drive system, particularly under low frequency.They also are suitable for being used in the little space such as cubicle, automobile etc. well.The diversity of dynamic loudspeaker and the simplicity of its operation (a motion awl) have given unbroken substantially leader position, are better than electrostatic loudspeaker and are used for the audio duplicate other system.And such development occurs, although need that expensive and complicated audio frequency control system is mixed, intersection, equilibrium, and relevant issues like this piece are listed in by with reference to the U.S. Patent application Serial No.08/684 that is included in here, in 311.
Although dynamic loudspeaker has market intensity, electrostatic loudspeaker industry provides remarkable potentiality for commercial interest.Yet because low-power output, large scale requires and build restriction, electrostatic loudspeaker fails to obtain the significant market share-less than 1%.Ignore in audio frequency industry the obvious advantage of being supplied with by electrostatic loudspeaker and surpass dynamic loudspeaker, that business development and research continue to concentrate on is high-power, magnetic drives on the dynamical system.
May seem that now this trend in acoustics circle also can influence the research direction in the parameter field of sound reproduction.Specifically, all parametric studies of the reality before the present inventor all are the uses for the bimorph transducer, structurally are similar to the dynamic loudspeaker with its high-power operation.As mentioned above, the bimorph system does not also have to realize for the essential result of the commercialization of Parametric Loudspeaker System.Do not realize requiring the volume and the quality of level by means of a ultrasound emission body of " high-power " form (bimorph transducer), by those skilled in the art a kind of so obvious hypothesis is arranged, static or low-power membranous type emitter are more impossible to be operated in the parameter sound field.So the use of wide barrier film and similar single-stage electroacoustic converting system do not think to be suitable for the transducer of parametric studies.
The acoustics science know for a long time movable electrostatic film or with a stator or actuator is relevant and with the film of its insulation as loud speaker/or the microphone device use.The typical structure of this device comprises a flexible Mylar (tm) or Kapton (tm) film, and it is metalized coated that this film has of being separated by an air gap or insulating material; With a relevant conduction, rigid plate.The voltage that applies that comprises sound or ultrasonic signal is sent to this capacitive component, and operation is moved flexible emitter film to propagate the ultrasonic or acoustic compression ripple of wishing.
Exist the static of two kinds of main kinds to raise device.Single ended speaker comprises individual plates, and this plate generally has the hole that allows sound to pass through.Film is suspended on the front or the back of plate, and can not move contiguously with plate by pad.With regard to the ultrasound emission body, film has shifted into the irregular surface of plate and has directly contacted, and allows film to vibrate in hole or cavity.The insulation barrier of air, plastic film or a similar non-conducting material is clamped between film and the plate, to prevent the electric contact and the starting the arc.Usually, plate and barrier film are connected on the DC power supply, to set up opposite polarity on the relative conductive surface of metalized coated and plate.
The electrostatic loudspeaker of the second main kind is by recommending the configuration expression.In this case, loud speaker has two rigid plate that symmetry is placed on each side of a conductive film.When applying voltage, it is negative that plate becomes with respect to film, and plate presents positive charge relatively.The effect of recommending to film is strengthened in variable voltage (for example exchanging) to the transmission of transducer, increases power output thus.The theory of static emitter design commonly used and the other details of structure be at the ELctostatic of Ronald Wagner Loudspeaker (static loudspeaker), and Audio Amateur Press finds in 1993.
Decision-orientated study for many years produces various technological improvements to this system, but the component definition keeps identical basically.Beyond thoughtly be that the present inventor has been found that this low-power transducer as piezoelectric film, static film, and the single-stage transfer process of other similar film emitters, for the parameter loud speaker provides significant advantage.Following disclosing provides further enhancing to above these notions narrated and embodiment in referenced patent application.
Summary of the invention
Therefore one object of the present invention is, a kind of film transducer is applied to the parameter field of sound reproduction.
Another object of the present invention is, provides a kind of and can respond the improvement loud speaker barrier film that electric excitation produces the large amplitude compressional wave, and this barrier film does not need a kind of rigid diaphragms structure of conventional audio speaker or ultrasonic transducer.
Other purpose of the present invention is that making the barrier film for the every part of given total amount system's output driving air is continuous basically.
Another object of the present invention is, makes a kind of transducer can carry high output to make distortion, phase deviation simultaneously, reach the harmonic resonance minimum.
Another purpose of the present invention is, makes a kind of transducer can be configured to provide the control of main frequency directional pattern, thereby beamwidth can expand to the diameter of transducer system even bigger.
A further object of the present invention is, can reduce weight and rigidity requirement by the stator component that a kind of foamed material is used as speaker system.
Another object of the present invention is, provide one can be single or recommend plate or the strutting piece of operating in the configuration.
Another object of the present invention is, produce at least a new sound wave or the infrasonic wave with commercial receivable volume level indirectly by using magnetic to drive film emitters, this film emitters provides interference between at least two ultrasonic signals with the different frequency that equals at least one new sound wave or infrasonic wave.
Another object of the present invention is, a kind of low-power of a homophase operation, array of emitter portion commonly used of having is provided.
A special purpose of the present invention is, a kind of piezoelectric film that has the arc emitter portion of being powered by a parameter signals source through single contact usually is provided.
Another purpose of the present invention is, makes the continuous basically barrier film that has an arc emitter portion array generally under unsaturated level and to be used for the making maximum controlled way of total system output drive the adjacent area of surrounding air.
These and other purposes realize that according to the method that produces the output of parameter audio frequency in the reciprocation as airborne a plurality of supersonic frequencies of nonlinear dielectric described method comprises step with a kind of being used for:
A) produce an electronic signal that comprises at least two ultrasonic signals, these two ultrasonic signals have the poor of the value that drops in the sound frequency rate scope;
B) electronic signal is sent to directly and Air Coupling as the electroacoustic film transducer barrier film of the part of single-stage conversion process of energy;
C) electronic signal at the barrier film place is directly changed into mechanical displacement, as an actuator of a parameter loud speaker;
D) at least two ultrasonic signals are transmitted into the air from barrier film machinery, as ultrasonic compressional wave; And
E) interact aerial ultrasonic compressional wave to produce the output of parameter audio frequency.
An alternative embodiment of the invention is a kind of loudspeaker device, and this loudspeaker device has: a rigidity emitter plate comprises an outer surface that has a plurality of apertures or cavity; A thin piezoelectric film, stride across the aperture arrangement of emitter plate, film is expanded in the cavity or from its expansion applies the variation contraction of electric input and an array that arc emitter disposes that extends, produce compressional wave in the environment around thus to form to respond at piezoelectric film; And electric contact device, be coupled to and be used to provide on the piezoelectric film that applies electric input.This device be realized or be extended to the array of arc emitter configuration can by positive or negative pressure.
Another one embodiment of the present invention is characterised in that a kind of method that is used for improving the output of parameter audio frequency, the method comprising the steps of: a) produce the electronic signal of at least two ultrasonic signals, these two ultrasonic signals have the poor of the value that drops in the sound frequency rate scope; B) electronic signal is sent to an emitter film transducer diaphragm that has an array of the arc emitter portion that is formed in the film; C) with an actuator of a parameter loud speaker in phase electricity-machine move the array of arc emitter portion; D) at least two ultrasonic signals are transmitted into the air from barrier film, as ultrasonic compressional wave; And e) interacts aerial ultrasonic compressional wave to produce the output of parameter audio frequency.
Also by a kind of method representation that is used for improving the output of parameter audio frequency, the method comprising the steps of in the present invention: a) produce an electronic signal that comprises at least two ultrasonic signals, these two ultrasonic signals have the poor of the value that drops in the sound frequency rate scope; B) simultaneously electronic signal is sent to an array that is formed on an arc emitter portion in the electroacoustic transducer barrier film commonly used; C) mobile in a controlled manner emitter portion is so that make the saturated minimum of surrounding air; D) with an actuator of a parameter loud speaker in phase electricity-machine move the array of arc emitter portion; E) at least two ultrasonic signals are transmitted into the air from barrier film, as ultrasonic compressional wave; Reach the aerial ultrasonic compressional wave that (f) interacts to produce the output of parameter audio frequency.
Another one embodiment of the present invention is described as a kind of method that is used for improving the output of parameter audio frequency, this method is based on step: a) produce an electronic signal that comprises at least two ultrasonic signals, these two ultrasonic signals comprise a ultrasonic carrier signal and at least one other ultrasonic signal, have one and drop on the poor of a value in the sound frequency rate scope with respect to carrier signal; B) electronic signal is sent to an array that is formed on an arc emitter portion in the electroacoustic film transducer barrier film commonly used, this barrier film has a propagation main shaft; C) with the array of general concave form configuration emitter portion, so that so that the convergence of emission ultrasonic beam to be provided from least one neighboring of array with respect to a predetermined convergence angle propagating main shaft; D) with an actuator of a parameter loud speaker in phase electricity-machine move the array of arc emitter portion; E) at least two ultrasonic signals are transmitted into the air from barrier film, as ultrasonic compressional wave; Reach the aerial ultrasonic compressional wave that (f) interacts to produce the output of parameter audio frequency.
An alternative embodiment of the invention a kind ofly has the wide frequency ranges capacity and compares the equipment that has than the ultrasound emission body device of macromesenterium displacement with the typical electrostatic diaphragm movement and realize with being used for by a kind of method.This device comprises the magnetic core spare that can set up first magnetic field.Movable barrier film stretches along magnetic core spare, and moves a short separating distance from magnetic core spare, with provide a barrier film with respect to the orthogonal translation of magnetic core spare the expectation scope and one of magnetic field by force partly in.At least one, little quality, plane, the conductive electric wire circle is arranged on the movable barrier film, and comprises first and second contacts that are used for making the electric current flowing through coil.A kind of variable current flows and is applied on the coil so that produce one second magnetic field, this second magnetic field changeably with first magnetic field interaction, so that in order to comprise a generation that has with a series of ripples of the ultrasonic frequency range of the sound signal of its modulation, attract and repel barrier film with hope frequency.
At a different aspect of the present invention, the emitter that is used for a parameter loud speaker comprises a drum of being made up of single emitter film, this film is arranged on the emitter commonly used surface of being made up of a plurality of apertures wherein, wherein aperture is aimed at, so that all frequencies that emission produces from it along parallel axes, and wherein in drum and in emitter film back, produce, eliminate backward-wave thus and produce near vacuum.
In another aspect of the present invention, emitter comprises a drum of being made up of single emitter film, and this film is arranged on the emitter commonly used surface of being made up of a plurality of apertures wherein, but wherein adds drum pressure now.
Description of drawings
According to the following detailed description of the most preferred embodiment of doing in conjunction with following accompanying drawing, for those skilled in the art, the other objects and features of the invention are obvious.
Fig. 1 a represents to use the prior art parameter loudspeaker of a plurality of piezoelectric bimorph transducers.
Fig. 1 b represents to use micropkonic another embodiment of parameter of a plurality of piezoelectric bimorph transducers.
Fig. 1 c is the figure that listens the point place to drive air in the space and cause the bimorph transducer of shock wave.
Fig. 1 d is the figure that drives the film transducer of the present invention of air in the even mode that distribute to drive and reduce shock wave.
Fig. 1 e is below the shock wave level and at the figure of the primary frequency waveform at shock wave level place.
Fig. 2 is the quadrature vertical view that is used for a circular V-arrangement fluting back plate of an extensive static film transducer.
Fig. 2 a is the cutaway view of plate and barrier film behind the static of Fig. 2 of obtaining of 2a-2a along the line.
Fig. 2 b is the figure that has the electrostatic transducer of crooked back plate and barrier film.
Fig. 3 is a kind of figure of piezoelectric film of rectification sinusoidal form.
Fig. 3 a is a kind of figure of piezoelectric film of the rectification sinusoidal form that has quarter-wave back plate at interval.
Fig. 3 b is a kind of figure of piezoelectric film of shallow rectification sinusoidal form.
Fig. 3 c is the figure of the piezoelectric film of the shallow rectification sinusoidal form of plate after a kind of having.
Fig. 4 is a kind of figure of sinusoidal shaping piezoelectric film.
Fig. 4 a is a kind of figure that has the sine shaping piezoelectric film of plate after.
Fig. 4 b is a kind of figure of sine shaping piezoelectric film of bending that has plate after one and open the angles of directivity of primary frequency.
Fig. 4 c is a kind of figure that is used in the sine shaping piezoelectric film in bipolar primary frequency/bipolar secondary frequencies pattern.
Fig. 5 is the figure of plate behind the piezoelectric film with concave or middle asperity form.
Fig. 5 a is the figure with the piezoelectric film of middle asperity form use.
Fig. 5 b is the figure with the piezoelectric film of concave dimpled grain form use.
Fig. 6 represents the prior art parameter loudspeaker of multiple pressure electricity bimorph transducer as a ultrasound emission source.
Fig. 7 represents to use micropkonic another prior art of parameter embodiment of multiple pressure electricity bimorph transducer, and is illustrated in the various defectives in the speaker performance.
Fig. 8 is the stereogram that rouses transducer according to a kind of emitter that principle of the present invention is made.
Fig. 9 is a vertical view, is illustrated in a plurality of apertures in the emitter surface of emitter drum transducer.
Figure 10 is the profile diagram of analysing and observe on emitter drum transducer and emitter surface, and expression is arranged in the film of the aperture top in the emitting surface.
Figure 11 A-B is the closed contour figure of the film that stretching on a plurality of apertures in the emitter surface when vibrating.
Figure 12 is a curve chart, is illustrated in an example of the relation curve of (piezoelectric film) displacement of film in the most preferred embodiment and frequency.Resonance frequency and typical bandwidth that this graphical representation produces.
Figure 13 be wherein pressurize of emitter drum can select embodiment emitter drum transducer analyse and observe profile diagram.
Figure 14 is a kind of more specifically enforcement of the present invention, and a ultrasonic fundamental frequency and a ultrasonic information carrier frequency that emission acoustics mixes are to produce a new acoustic frequency or subaudible frequency.
Figure 15 is the stereogram that has the transducer of a barrier film of having finished the concave elliptical shape.
Figure 16 is the cross section of Figure 15, and expression has vibration and produces a kind of hyperacoustic transducer of finishing film.
Figure 17 is a kind of single-ended sectional side view of electrostatic loudspeaker.
Figure 18 represents a kind of with the single ended speaker device of a foam element as a stator.
Figure 19 represents a kind of bowed shape, and representative is used for a kind of curved profile of current loudspeaker device.
Figure 20 represents a kind of cylindrical shape, and representative is used for a kind of of loudspeaker device may profile.
Figure 21 is a kind of schematic diagram of citation form of a kind of foam stator loud speaker embodiment of loudspeaker device in recommending configuration.
Figure 22 represents that film wherein is clamped in of loudspeaker device between the relative foam stator
Embodiment.
The multimembrane embodiment of Figure 23 and 24 expression loudspeaker device.
Figure 25 is a top perspective view, represents a kind of thin-film membrane that is arranged on the emitter barrier film and is suspended on a plurality of conductive coils of a magnetic core element top that has.
Figure 26 is the decomposition view that can select embodiment, is illustrated in the relative conductive coil on emitter barrier film and the magnetic core.
Figure 27 be analyse and observe, top perspective view, represent that a kind of band is arranged on the emitter barrier film and is suspended on the thin-film membrane of a plurality of conducting rings of magnetic core element top.
Figure 28 is the amplification stereogram of the tuning static emitter of a kind of resonance.
Figure 29 is the cross section of the emitter of Figure 28.
Figure 30 is a kind of sectional side view of hemisphere electrostatic loudspeaker.
Figure 31 is a kind of solid, phantom of hemisphere electrostatic loudspeaker.
Figure 32 is a kind of three-dimensional side view of hemisphere electrostatic loudspeaker.
Embodiment
Below with reference to accompanying drawing, various elements wherein of the present invention will provide the numeral indication, and wherein the present invention will be discussed, so that make those skilled in the art can implement and use the present invention.Be appreciated that following description only is demonstration of the present invention, and should not be regarded as restriction claims subsequently.
Fig. 1 a and 1b are the figure that the prior art parameter loud speaker 10 of a plurality of piezoelectric bimorph transducers 11 is used in expression.These use to the string that surpasses 1500 bimorph transducer with 500.Be for one of micropkonic difficulty of parameter, when under ultrasonic wave, driving air so that suitable conversion efficiency and the loudness under secondary generated frequency to be provided, can be in air driven to the shock wave limit, wherein fundamental frequency can not become louder, and has only the distortion component level to increase.This shock wave limit when drive air space each, poorer during point.Out-of-limit system intensity, the easy more existence of shock wave.
Fig. 1 c is one group of figure that each point place in space 12 drives air and causes the bimorph transducer of shock wave.Fig. 1 d is the figure that drives of the present invention a kind of film transducer 13 of air with distribution driving 14 and the even mode that reduces shock wave.A slice piezoelectric film 18 separates with charging pedestal 17, thereby when a signal is applied on the pedestal 17, produces a kind of mechanical interaction.Fig. 1 e is in the shock wave level below 15 and at the figure of the primary frequency waveform at shock wave level 16 places.
An a kind of most preferred embodiment of extensive film transducer is based on the static driven principle.One of the transducer use of electrostatic type has near plate after the conduction of a conducting film of back plate.A bias voltage is applied on film or the back plate, and film and back plate are all by two polarity driven of drive signal.Fig. 2 is a vertical view that has the extensive static film transducer of a circular V-arrangement fluting back plate 21, and Fig. 2 a is its cutaway view.Back plate structure can be at alternately recessed (concave) or ripple (convexity) in shape.
When high frequency when penetrating than macromesenterium, compare with interested frequency wavelength, wave beam can reach high like this directivity, thereby high-frequency is assembled and is reduced to a narrow beam.This can cause that the directivity of undue concentration and the too early shock wave of sound wave form because high strength is focused in the little spatial domain.By crooked barrier film, can open radiation pattern, to have a directivity window that on width, is more or less the same or even wide slightly sound distribution that makes the limited waveform minimum of shock wave with transducer.Fig. 2 b represents the static film transducer of a complementary shape film barrier film 22 that has a crooked back plate 23 and address this problem.
An alternative embodiment of the invention is utilized the piezoelectric film of being made by polyvinylidene fluoride (PVDF).This film expands when electric excitation and shrinks, and therefore must be out of shape and export with realization sound.Should be realized that these large tracts of land film transducers include but not limited to static film, foil electret, the piezoelectric film such as PVDF, electric heating mechanical membrane, reach plane magnetic configuration.
A kind of optimum shape as the piezoelectric film 30 of rectification sinusoidal shape is illustrated among Fig. 3.Fig. 3 a is a kind of figure of piezoelectric film 30 of the rectification sinusoidal form that has quarter-wave back plate 31 at interval.By a back plate 30 is separated 1/4th of a wavelength 35 with film, the output of emitter is can increase up to 3dB under four times the frequency of the distance from film to the back plate at its wavelength.Fig. 3 b is a kind of figure of piezoelectric film 32 of shallow rectification sinusoidal form.Fig. 3 c is a kind of figure that makes back plate 31 and piezoelectric film 32 separate the piezoelectric film 32 of quarter-wave shallow rectification sinusoidal form.
Fig. 4 is a kind of figure of sinusoidal shaping piezoelectric film 42.This form may be effectively, makes the motion of all films can be as a kind of projectile configuration.For much larger than or much smaller than 1/2 the sinusoidal shape of crest to the wavelength (wL) of crest height, crest 43 and trough 44 be out-phase each other.In this case, may need a compensation process, as with the electric anti-phasely driving crest of trough.Fig. 4 a is a kind of figure that has the sine shaping piezoelectric film emitter 42 that separates back plate 41.Fig. 4 b is a kind of figure of sine shaping piezoelectric film 45 of bending 47 that has plate after one 46 and open the angles of directivity 48 of primary frequency.This layout makes shock wave form minimum, and opens the window of dispersion, as in the above-mentioned static example.
Most of ultrasound emission bodies and parameter loudspeaker are one pole basically in radiation pattern.As shown in Fig. 4 c, by means of the present invention by use one open film (for example PVDF) and need not the back plate can realize a kind of bipolar parameter loudspeaker, this loudspeaker with the radiation of a kind of bipolar out-phase radiation pattern, is operated in a kind of bipolar homophase mode for all secondary parameter drive signals in the primary frequency scope simultaneously.This can be used in wants to penetrate place high orientation, homophase sound on two rightabouts.This is unpractiaca for any prior art device.Fig. 4 c is a kind of figure that is used in the sine shaping piezoelectric film 41 in bipolar primary frequency/bipolar secondary frequencies pattern.
The another kind of iris-diaphragm that is used for piezoelectric film is a kind of concave or protrusions ripple struction.This shape can realize by the thermosetting film, or utilize the foam support structure that film is forced into this shape.Film is formed crooked emitter portion also can be realized by with plus or minus pressure film being pushed away or pulls into cavity.In addition, might utilize foam or plastic supporting structure that film is forced into desirable shape.
Fig. 5 is a kind of figure that has the piezoelectric film 51 of the back plate 52 that produces concave or convexity form.The pressure compacting of the chamber 54 usefulness plus or minus in the plate 52 of back is to produce concave or convexity ripple.These chambers 54 can be suppressed discretely, and perhaps they can be the parts of a bigger pressure chamber that interconnects.Fig. 5 a is the figure with the piezoelectric film 51a with concave shape of the form use that ripples.Fig. 5 b is the figure with the piezoelectric film 51b of the form that the ripples use of middle raised character.Those skilled in the art will understand, can be used for producing in piezoelectric film under notion of the present invention and wish crooked numerous variations.And, can develop multiple supporting mechanism, so that the bending of these hope to be provided, especially when the generation of the parameter output that is applied to audible sounds, as the time from a kind of emission of main ultrasound emission in piezoelectric film.
A kind of applicability of flexible film barrier film provides a plurality of advantages that surpass conventional rigidity bimorph device.Some of these benefits more specifically show in Fig. 6 and 7.Fig. 6 represents to use a kind of prior art parameter loudspeaker 60 of a plurality of piezoelectric bimorph transducers 62.As described, in the process of being devoted to produce efficient parameter output, these have been used for the string between 500 to 1500 bimorph transducers.The disclosure has picked out the urgent a kind of defective that produces in the saturation of the air at transducer face preceding office portion emitting area place in the bimorph emitter.The other defect that Fig. 7 shows by a diagram that this distortion reason and produces from prior art parametric arrays 64 owing to the reason of phase distortion and mis-alignment.These are not suitable for, and phase anomaly is illustrated in the bimorph 70,71,72 and 73 of Fig. 7 as mentioned.
Be noted that importantly these bimorph emitters are the isolating constructions that generally have different physics and electric property.Really, for different structural environments, this bimorph transducer can be by difference made in batches.Typically, they are thrown away in the free warehouse, and specify the concrete structure specification selecting to be assigned as the client on the basis at random.As a result, the mistake of the phase place in propagate ultrasound waves 66 coupling can cause phase cancellation and other forms of sound to reach by dotted line 77 and 78 directional distortions of representing.The flecition of the adjacent ultrasonic beam of 78 expressions is wherein from each frequency out-phase of each emitter.For example, emitter 70 propagating with from the ripple of emitter 71 ripple of out-phase a little.Dotted line 78 shows that this skew results from the phase place mis-alignment from the direction skew of the audio frequency output of parameter loud speaker.Emitter 72 tilts to install, and as being shown by acute angle 69, it departs from a vertical axis 76 supporting bracket 65 being installed with respect to one a little.Here same, do not aim at from the wave beam that emitter is propagated, and the phase place of suitably aiming at causes energy loss and possible distortion.Because these factors multiply by 500 to 1500 emitters that generally are combined to form a conventional arrays, so adverse effect may be significant.In addition, obviously these devices often have multiple harmonic resonance and antiresonance, and these resonance are further distortion in the micropkonic demodulation audio frequency of parameter component.
Except that more than the phase anomaly distinguished, Fig. 7 represents the saturation problem of above introduction.Really, one of the present inventor of difficulty noticed by to(for) the parameter loudspeaker is, when driving air, can not become air driven louder and have only in the shock wave limit that distortion component increases on level to a kind of wherein fundamental frequency with the ultrasonic wave that suitable conversion efficiency and loudness are provided.This shock wave limit drive the spatial domain less, each the time increase, as occurring for bimorph transducer 73.Out-of-limit system intensity, the easy more existence of shock wave.This sets up for the high strength device such as conventional bimorph especially.
The present inventor has been found that by high energy level being distributed on the broad surface area of film, and is opposite with the localization emitter elements of bimorph array energy transducer, can control the shock wave limit.When the array of a little bimorph emitter of expectation produces the sound pressure level (SPL) of wishing when 130db is supplied to emitter, the LPS deficiency of hope, and distortion is amplified widely.
Under principle of the present invention, a broad transmitting film is to supply with less than 120db.Yet, on a plurality of little emitter portion that energy is dispersed in film, can be at any partial points place of transducer front air driven to saturated or shock wave.The conversion efficiency that the parameter that is used for being produced by the film emitter is exported is very high, and reduces distortion widely.A kind of break-in of this procedural representation from attempting to increase the prior art of volume from the higher db of high strength emitter (as bimorph) output by assembling.
In general, a kind of method that in as a kind of air of nonlinear dielectric, improves the output of parameter audio frequency of these various representation of concept according to the interaction of a plurality of supersonic frequencies.One or more of structure by former type are implemented following basic step.Below these steps are listed in, and comprise:
A) produce an electronic signal that comprises at least two ultrasonic signals, these two ultrasonic signals have the poor of the value that drops in the sound frequency rate scope;
B) electronic signal is sent to an emitter film transducer diaphragm that has the array that is formed on the arc radiating portion in the film;
C) with an actuator of a parameter loud speaker in phase electricity-machine move the array of arc emitter portion; And
D) at least two ultrasonic signals mechanically are transmitted into the air from barrier film, as in air, interacting to produce the ultrasonic compressional wave of parameter audio frequency output.
Another selectivity step is to select a kind of like this transducer diaphragm, and the latter has the size greater than the wavelength of the supersonic frequency under its low-limit frequency wavelength value.A kind of expansion of this conception of species is to select a kind of like this transducer diaphragm, and the latter has the size greater than ten times of the wavelength of the supersonic frequency under its minimum.
At prior art by increasing the place of seeking to increase SPL output in the db level of each bimorph emitter surface, the present invention energy dissipation on big surf zone.Although this has reduced the db level of the compressional wave that any some place propagates in the space, whole effect is to increase SPL, because surface area is bigger.And, because distortion is reduced, so can be elevated to more effective level to SPL.One of this expression is restricted to electronic signal the notion step that makes in the maximum intensity level of the saturated minimum of each arc emitter portion place surrounding air.Following geometry and relevant db level show the appropriate balance of the extensive geometry of the db emitting stage with film emitter.
The another one step of implementing easily under notion of the present invention relates to, and provides from the improvement of each wave beam of the ultrasonic energy of each propagation of film emitter portion to aim at.The orientation of wave beam can be by the supporting construction control of back plate.Specifically, plate structure independent, commonly used provides the physical positioning of the array of emitter portion with degree of precision.The bimorph device need the location respectively of each emitter with prelocalization, cause mis-alignment.By means of all emitter portion of suitably aiming at, aim at ultrasound emission.The interactive interference of out-phase that significantly reduces to come free non-aligned emission to produce is lost.Consider virtual end-fired array, also provide more effectively conversion than the ultrasonic energy of narrow beam from the demodulation of the sound signal of ultrasound emission.Specifically, provide more concentrated for demodulation, increase audio frequency SPL thus along ultrasonic beam length than the narrow beam pattern.
An alternative embodiment of the invention is Fig. 8 of a more efficient embodiment of a ultrasound emission body of expression.In the most preferred embodiment of representing in this stereogram, emitter drum transducer 100 is general columniform objects.The sidewall 106 of emitter drum transducer 100 is metal or metal alloy preferably.The outer surface on emitter surface 102 comprises a piezoelectric film 104.Piezoelectric film 104 is encouraged by the signal of telecommunication that is applied on it, and causes that vibration is to produce compressional wave under hope frequency.On piezoelectric film 104 and around the periphery on emitter surface 102 are conducting rings 114.Conducting ring 114 is used for voltage is applied on the piezoelectric film 104.After piezoelectric film is for 104 times, will describe one wish metal cake (but hereinafter be called dish, see Fig. 9).
In order to understand the structure of emitter drum transducer 100 better, Fig. 9 provide of the dish 108 that is arranged in below piezoelectric film 104 (see figure 8)s towards the outside 126 vertical view.In this most preferred embodiment, dish 108 is metals, and is equipped with a plurality of apertures 112 of general uniform-dimension.Aperture 112 passes completely through dish 108 thickness and extends to towards the outside 126 from one towards inboard 128 (see figure 10)s.In order to provide predictable and maximal efficiency performance, if use two-way piezoelectric film, then aperture 112 is with cylindrical formation.In the place of using one-way membrane, elongated shape indicated among Figure 15 is wished.
Option table is shown in the aperture pattern 112 in Fig. 9 mid-game 108 in this case, because it can make the aperture 112 of maximum quantity be arranged in the given area.This pattern general description becomes " honeycomb " pattern.Selecting honeycomb pattern, is because because the characteristic that acoustics mixes wishes to have the aperture 112 that has parallel axes in a large number.Particularly producing under the situation of supersonic frequency, wishing between the frequency of a fundamental frequency and a carrier wave information, to cause and mix interference, producing a new acoustic frequency or a subaudible frequency that comprises information thus.Therefore, the quantity of the fundamental sum information carrier signal that causes interference close to each other is big more, and the new acoustic frequency of generation or the volume of subaudible frequency are big more.In other words, the invention provides and produce a kind of loud remarkable advantage that is enough to commercial available volume.The parallel axes of frequency emission provides bigger predictability, will produce new acoustic frequency or subaudible frequency wherein so that determine.
Figure 10 provides the useful profile and the sectional block diagram of most preferred embodiment of the present invention, comprises and the relevant more details that is electrically connected of emitter being roused transducer 100.The sidewall 106 of emitter drum transducer 100 provides one to be used to coil 108 shell.Making its a plurality of apertures 112 pass dish 108 extends.Piezoelectric film 104 is expressed as and coils 108 and contact.Service test has determined that had better not be adhered to dish 108 to piezoelectric film 104 is on the whole exposed surface that contacts with piezoelectric film 104.The varying dimensions of the binding agent corner between piezoelectric film 104 and aperture 112 causes otherwise the uneven resonance frequency of aperture 112 generations uniformly.Therefore, most preferred embodiment is only lectured an outward flange of piezoelectric film 104 is bonded on the dish 108.
Be to eliminate expediently any possibility of unconscious generation " backward-wave " distortion about second reason of vacuum.In other words, by definition, compressional wave requires to have a kind of by its compressible medium that can propagate.If can make piezoelectric film 104 on by arrow 130 indicated directions, produce ultrasonic compressional wave from emitter drum transducer 100 " outwards ", then only logically, also the ultrasonic compressional wave that is producing from piezoelectric film 104 is in the opposite direction propagated, and enters emitter drum transducer 100 backward on by arrow 132 indicated directions.Therefore, these are propagated or the backward-wave distorted wave can disturb the ability of the piezoelectric film 104 that produces hope frequency backward.During surperficial in emitter drum transducer 100 is left in backward-wave reflection, this interference occurs, and propagates through an aperture 112 once more up to them, and reflects and leave piezoelectric film 104, changes its vibration thus.Therefore, be used for the medium that compressional wave is propagated, do not disturb the vibration of piezoelectric film 104 by eliminating in emitter drum transducer 100.
Figure 10 represents that also electrical lead wire 120 is arranged, and electrical lead wire 120 electrical couplings are to piezoelectric film 104, and carry out will be from the electric expression of the frequency of each unit 124 emission of emitter drum transducer 100.On some signal sources 122 shown in these electrical lead wire 120 electric being connected to.
Figure 11 A is the closed contour figure (being included in two piezoelectric films 104 on the aperture 112) of two unit 128 among Figure 10.Piezoelectric film 104 is shown as to inwardly (from its original-shape 104a) expansion of the inside of emitter drum transducer with the exaggerative vibrometer that only is used for illustration purpose.From with Figure 11 B relatively should be understood that following outwards and away from the expansion of emission drum transducer inside of piezoelectric film 104 to intramedullary expansion.Piezoelectric film is inwardly only represented for illustration purpose is exaggerative with the amount that expands outwardly.The actual amount of expansion is discussed later.
Figure 12 is a curve chart, and the frequency response (as the function that applies voltage RMS) of the emitter drum transducer of producing according to the principle of most preferred embodiment is compared in expression with the displacement of piezoelectric film.Emitter drum transducer result is the demonstration in emitter drum transducer inside typical consequence under nearly vacuum.With in this embodiment film (piezoelectric film 104) is the polyvinylidene fluoride (PVDF) of the about 28mm of thickness.In test, when using the driving voltage of 73.6Vpp, it is about 37.23kHz that the resonance frequency of this concrete emitter drum transducer is expressed as, and bandwidth is about 11.66 percent, and wherein 6dB frequency in upper and lower is respectively 35.55kHz and 39.89kHz.The peak swing of piezoelectric film displacement finds it is that about only crest above 1 micron is to crest.This displacement is corresponding to the sound pressure level (hereinafter being SPL) of 125.4dB.
Surprisingly, should result from use than big SPL and suppose an emitter drum transducer that bears 1680Vpp or compare the big 22.8 times PVDF that is applied in theory.Therefore, the theoretical limit of these concrete materials that use in emitter drum transducer causes surprising big 152.6 SPL.
To remember that importantly the resonance frequency of Biao Shi most preferred embodiment is the function of the various characteristics of emitter drum transducer here.These characteristics especially comprise the thickness (Fig. 8) that strides across the piezoelectric film 104 that stretches on emitter surface 108 and the diameter of aperture 112 in emission body disc 108.For example, use thin piezoelectric film 104 givenly to apply the very fast vibration that voltage will cause piezoelectric film 104 for one.Therefore, the resonance frequency of emitter drum transducer 100 is with higher.
The advantage of upper resonance frequency is, if the percentage of bandwidth remains about percent 10 or increase, as being represented by result of the test, then can easily produce the frequency of wishing scope.In other words, human auditory's scope is about 20 to 20,000Hz.Therefore, if bandwidth is wide as to be enough to contain at least 20,000Hz, then the result who mixes as acoustics can easily produce human auditory's gamut as a kind of new sound wave.Therefore, with signal a kind of suitable carrier-in-interference, that have on it information of modulation, will cause one can produce and stride across the whole new voice signal of listening the sub-audible sound of frequency spectrum of human auditory.
Except that using thin piezoelectric film 104 (Figure 10), the additive method that can realize this point is arranged to increase the resonance frequency.For example, can select among the embodiment at one, the present invention uses a unit 124 that has than the aperture 112 of minor diameter.Less aperture also causes upper resonance frequency for a driving voltage that applies.
Figure 13 represents currently can select embodiment than not convenient one of most preferred embodiment of the present invention, but this can select embodiment also to produce frequencies from a same emitter drum transducer 116 of building with most preferred embodiment almost.Essential distinction is, replaces in the inside of emitter drum transducer 116 and creates vacuum, and pressurization is inner now.
The pressure that is introduced in the emitter drum transducer 130 can change to change resonance frequency.Yet the thickness of piezoelectric film 104 is key factors of determining to apply much pressure.This can part owing to by having the piezoelectric film that quite anisotropic copolymer is made, rather than the two-way film such as PVDF.The adverse side effect of anisotropy piezoelectric film is that it may in fact prevent the vibration of film on all directions, causes causing from the asymmetry of harmful distortion of the signal of its generation.Therefore, PVDF is the optimal material that is used for piezoelectric film, not only because it has yield strength far above copolymer, and because it has quite little anisotropy.
A shortcoming of emitter drum transducer 130 is harmful frequency resonance or thorn point.These frequency thorn points can produce owing to the backward-wave in emitter drum transducer 116, because replace vacuum, a kind of elastic fluid is present in the emitter drum transducer 116.Yet, also determined to eliminate backward-wave to absorb reverse wave energy by a kind of material being placed in the emitter drum transducer 116.For example, a slice foam rubber 134 or other sound absorptions or attenuating material generally can be eliminated all frequency thorn points.
Use the result of the test of pressurization emitter drum transducer 130 to show, under typical selection pressure and driving voltage, emitter drum transducer is operated in the zone of substantial linear.For example, determine an emitter drum transducer that uses the thick PVDF of 28mm in emitter drum transducer, to have 10 pound per square inches (psi) pressure, can produce the resonance frequency of rousing transducer about percent 43 than emitter with 5psi internal pressure.In addition, when determining that doubling driving amplitude also generally doubles the displacement of PVDF, find general linear operating area.
Determined with test that also pressurization emitter drum transducer generally can obtain about percent 20 bandwidth.Build a kind of emitter that only has the 100KHz resonance frequency and rouse the bandwidth that transducer causes about 20KHz.This is more suitable for producing human auditory's gamut.The inside of rousing transducer 116 by the acoustic attenuation emitter is to prevent to introduce backward-wave distortion or low-frequency resonant, and pressurization embodiment also can realize the impressive result of the commercial available tones magnitude of most preferred embodiment of the present invention.
Forward a kind of of most preferred embodiment to and implement more specifically, emitter drum transducer can for example be included in the system shown in Figure 14.This system comprises the oscillator or the digital ultrasound wave source 220 that are used to provide a first-harmonic or carrier wave 221.This ripple 221 generally is called first ultrasonic wave or former ripple.A Modulation and Amplitude Modulation element 222 is coupled in the output of ultrasonic generator 220, and receives and to be used for the fundamental frequency 221 that mixes with sound or infrasound input signal 223.Sound or infrasound signal can be supplied with the analog or digital form, and can be music or other forms of sound from any normal signal source 224.If input signal 223 comprises the upper and lower sideband, then a filter element 227 is included in the modulator so that produce monolateral band output on modulated carrier frequencies.
Emitter drum transducer is expressed as label 225, makes its emission supersonic frequency f1 and f2 as a kind of new waveshape of propagating in the surface of transducer 225a.This new waveshape interacts in the nonlinear dielectric air to produce different frequency 226, as a kind of new sound wave or infrasonic wave.
The present invention can by as described in work because interact in air according to the principle that acoustics mixes with f1 and the corresponding compressional wave of f2.Acoustics is mixed with point image for the mechanical homologue that occurs in the electric immixture in the nonlinear circuit.For example, the Modulation and Amplitude Modulation in circuit is a kind of mixed process.Mixed process itself is the establishment of two new ripples simply.New ripple is two basic waves and and poor.
In acoustics mixes, to observe when at least two ultrasonic compressional waves interact in air or interfere, new ripple basic wave and that reach difference appears equaling.Best transmission medium of the present invention is an air, because it is a kind of height compressible medium of nonlinear response under different condition.Air this non-linear might make mixed process take place and without circuit.Certainly, if wish that any compressible fluid can both play transmission medium.
As described above, the acoustics immixture causes and establishment ultrasonic wave f1 and f2 and that reach corresponding two compressional waves of difference.Be the noiseless ultrasonic wave that does not have interest, and therefore not expression.Yet difference can be sound or infrasound, and is expressed as a kind of general unidirectional compressional wave 226 that results from interference region.
Although the successful generation of different ripples seems only have nominal volume in prior art, this configuration produces full sound.Can be although carry the single transducer of fundamental frequency and the monolateral band frequency of modulation with suitable distance and impressive volume level emission sound, the combination of a plurality of synteny signals enlarges markedly volume.When pointing to wall or other reflecting surfaces, volume is so big, thereby it reflects to such an extent that resemble wall sound generating source just.
A key character of the present invention is that fundamental frequency and monolateral band are propagated from the same transducer surface.Therefore, aim at component waves fully.And phase alignment is outside maximum, is provided at interference maximum level possible between two different supersonic frequencies.By means of the maximum interference of between these ripples, guaranteeing, realize ceiling capacity transmission to air molecule, this becomes " loud speaker " radiant element in the parameter loud speaker.Thereby the present inventor believes that this may produce the surprising increase of volume for audio output signal.
The embodiment of Figure 14 of an array of use emitter portion is because multiple reason is best on single film barrier film.For example, this system does not require the independent installation of bimorph device, and therefore can produce cheaply.However, a plurality of registration signal of the actual generation of monofilm transducer.And this system weight is light, volume is little, and the most important thing is to have maximal efficiency.Opposite with the device of prior art, present embodiment always produces a new compressional wave with maximal efficiency.This is because when using same ultrasound transducer 225 emissions to implement the new ultrasonic wave form 227 of two ultrasonic compressional waves, the orientation of two separation ultrasonic transducers never can be mated, and perhaps surpasses the complete coaxial relation that obtains.From this coaxial propagation that emitter rouses the single aperture of transducer, therefore produce maximum interference pattern and the most effective compressional wave and produce.
The development of the full volume ability in the parameter loud speaker provides the remarkable advantage that is better than conventional speaker system.The most important thing is to duplicate the fact of sound from the radiant element of less quality.In interference region, and therefore produce the position, do not have the direct radiation element at new compressional wave.Can eliminate distortion effect basically by this sound generating feature that acoustics mixes, the major part of these influences is caused by the radiant element of conventional loud speaker.For example, awl hyperharmonic awl imbalance can be revised one otherwise have the pure sound reproduction signal of harmonic wave and standing wave on speaker awl.
This improvement will be the most significant when comparing with the prior art restriction of conventional loud speaker barrier film.It is not real flat frequency response that a direct physical radiant element for example has a kind of.But it is the intrinsic function that preferably is suitable for the frequency type (low frequency, intermediate frequency or high frequency) of launching.Although loudspeaker shapes, physical dimension, and form the directly intrinsic loudspeaker performance of influence, the generation of acoustics mixings ripple utilizes the natural response of air, so that avoid physical dimension and composition problem, and realization is for the real flat frequency response of sound generating.Can receive the realization of amplitude level by means of sound, parametric system now can with commercial enforcement the in conventional loud speaker direct competitive ground-a kind of result who not have realization so far by prior art parameter or pulsation hybrid device.
Undistorted sound means that the present invention keeps the phase coherence with respect to original record sound.Conventional speaker system does not have this ability, because for the propagation by the most suitable speaker element (woofer, middle pitch or high pitch loudspeaker), frequency spectrum is divided by a crossover network.By eliminating radiant element, the present invention makes conventional crossover network and phase control out-of-date.This can realize the virtual of sound or near point source.
Other advantages directly result from unique essence of ultrasonic film transducer.Because its small size and little quality, such transducer are generally without undergoing the defective of multiple restriction and the conventional radiant element that uses in loud speaker.And, avoid distortion, harmonic wave and other redundant character that in low frequency, intermediate frequency and high-frequency range, must directly duplicate the direct radiation element of sound in the use of ultrasonic transducer under the high frequency.Therefore, a kind of multiple good acoustic performance of remarkable undistorted ultrasound transducer system can indirect conversion become sound or infrasound sound byproduct now.
Figure 15 and 16 discloses the piezoelectric film barrier film of the use that does not need pressure to apply and rouse and another embodiment of supporting bracket.The transducer 160 that shows comprises a substrate 161 and the support membrane barrier film of being made by piezoelectric 162.Electrical contact on film makes voltage application become possibility, and is as discussed above.Arc emitter portion 165 mold pressings or be thermoformed into a kind of stable configuration.Corresponding cavity in the top surface of supporting bracket 161 or opening are aimed to receive the sweep of film.These cavitys have enough degree of depth, freely move to allow emitter portion, do not contact and do not cause with the interference of cavity wall 167.The flat part 162a of intermediate surface 168 contact membraneses of supporting bracket, and stabilising membrane and emitter portion are so that suitably aim at collimation propagation axis 70 as showing.The homophase operation takes place, and applies voltage to produce the monolithic construction of homophase and the compressional wave of suitably aiming at 172 because film is a kind of response equably.
Supporting bracket 161 can be built by any rigid material that the ability of stablizing emitter film 162 is provided for proper operation.Conductive plate can be used for replacing contact 163, and signal voltage can be applied on the piezoelectric film.The piezoelectric film that shows comprises a co-polymer membrane with the one-way response that strides across elongated emitter portion orientation, as being shown by line 174.This is opposite with two-way film such as PVDF.One-way membrane make its geomery about 80% along horizontal 174, and therefore provide good response.By means of the large-size of arc emitter 165, increasing surface area provides favourable SPL output.
But Figure 17 shows and a kind ofly implements method of the present invention by means of the system of selection that is used for forming emitter portion 180.This depends on by one and has the displacement that becomes an integral type flat board of arc piezoelectric with the supporting bracket 183 of the flange 184 of wishing emitter shape configuration.Apply a power F the film on the flange is out of shape by illustrated.This power can be that the periphery from film applies film being pasted the tension force of flange tension, or other proper methods.Flange wishes to be made so that the voltage fluctuation that the piezoelectric film response applies by foamed material.
The foam stator that another one of the present invention can be selected embodiment to use to have a static barrier film is to produce the ultrasonic parameter compressional wave.Figure 18 represents that one makes ultrasonic output 311 at the single ended speaker device of forwards propagating 310 on 312.This loud speaker can be coupled on the ultrasonic drivers 313, and ultrasonic drivers 313 provides and is used for supplying with various electronic circuit support components of wishing signal discussed above.
This device comprises that variable voltage that a response applies launches the static emitter film 315 of ultrasonic output.Emitter film comprises a plastic plate and thin metal coating or other conductive surfaces.The static emitter film also is well-known, has been applied to hereinafter generally be called the multiple capacitive character or the layering Charge System of electrostatic devices.Usually, plastic plate is can be as Mylar (tm), Kapton (tm) or other non-conductive compositions of the insulator between metal level and stator film 320.Surface or coating with partially conductive can be used for producing the CHARGE DISTRIBUTION that evenly strides across membrane surface.An optimum range of resistivity is greater than 10K ohm.This provides less charge migration, and prevents to cause the accumulation of static electricity of the starting the arc.Higher impedance as 100M, is of little use in this purposes.Obviously, this selection also influences the electric capacity between two boards.
One of principal character of this embodiment of the invention relates to the use as a foam element of stator 320.Stator plays one with respect to basic part or stiffener light, that flexible transmitting film 315 provides inertia.This stator is a conducting element that a kind of polarity is supplied to capacitor bank.The resistivity of this element is chosen to promote uniform charge migration, to avoid hyperarc and intrinsic other adverse effects in electrostatic system.A kind of optimal components that has shown effective performance is the conventional static packing foam (generally being called " conductive foam ") that is used as about the packaging material of computer and other charge sensitive contents.This material operation provides the Electro-Static Discharge from senser.It not only protection component avoid harmful discharge or expose, and weight is very light and low price.It typically is formed in a kind of conventional foam mold pressing device with actual Any shape, density or size.
The prior art of material uses generally to be limited to always and its objective is the passive role (packaging material) who only protects senser.As other packaging material, utilance is based on being used for the interim placement in the space in filling cartons or the container.Usually, this material is thrown away with container, because there is not independent value.Its existence in the electronic market is thought natural always, and is confirmed by the enormous amount of burying on the whole world.
Accompanying drawing shows a kind of foaming composition that has hole at random or cavity.The use of applicable technology also allows in the plastics parent space than uniform-dimension.Therefore, for characteristic frequency purposes, resonance, and correlated performance can be tuning or optimize the stator composition.The rigidity of foam or rigidity are material property and hole density and the function that limits the wall thickness in each space or hole.Thereby, the further control of stator acoustic response, except that STOCHASTIC CONTROL with respect to even void size, can be by the variation control of multiple physical parameter.The importance of rigidity is well-known in stator component, and can partly be subjected to the influence of the new design factor relevant with the foaming composition uniqueness now.
Although the foam element that shows comprises a kind of open cell structure, combination open and closed cell structures also is suitable for.The advantage of open cell structure is the two-way propagation of sound.In Figure 18 embodiment,, suppressed this two-way situation by on the foam element rear surface, adhering to nonporous film 335.This film also can be replaced by the rigid member that plastics or a certain other rigid materials form.Rigid member can be adhered to so that conform to wishing the loud speaker profile.
For example, conventional electrostatic loudspeaker is the plane normally, because barrier film does not contact with stator, but is suspended on the stator front.Therefore be difficult to crooked barrier film in the path of bending and non-warping gap between stator and film.Yet for have directly the present invention of contact of emitter film on foam surface, a kind of curved profile is to form flat shape simply.Really, curved surface is supplied with the relative hope resistance of film with the part of finishing the bias capability that is used for strengthening contact.The equal advance of ability permission when configuration is used for the different shape on loud speaker surface with actual any form of foam mold pressing or shape.For example, loud speaker can be a curved surface shown in Figure 19, provides the improvement of sound transmission to disperse.The stator 380 of crooked Figure 19, and film 382 conforms to this bending.Profile can be a circumference, resembles a cylinder and a ball (not shown) among Figure 20.The stator 384 of Figure 20 is cylinders, and film 386 also forms a cylinder.Each of these embodiment provides and is difficult to particularly export for audio frequency to be included in the unique dispersion pattern in the electrostatic loudspeaker systems always.
Another one embodiment of the present invention provides and recommends operation, and shows in Figure 21.It comprises one first foam element, 359, the second foam elements 360 have one to front surface 361, magnetic core part 362 and a rear surface 363 in the middle of one.Second foam element be positioned at the opposite side of static emitter film 365 to front surface (being called second) away from first foam element to front surface.Second is made of supporting the static film the composition with enough rigidity to front surface, and comprise to second forward the surface can apply the performance of variable voltage to supply with the ultrasonic signal of wishing.Second to front surface 361 by a surface composition that comprises areola discussed above, make each cavity of surrounding wall structure qualification, described surrounding wall structure approximate and foam element to engagement edge place termination that front surface overlaps.The lip-deep forward film applying device (not shown) that is used for the static film is coated to second foam element is followed the form that resembles above single-ended embodiment.As described above, bias unit 366 is connected on second foam element so that film is biased to second engagement edge to front surface 361 directly contacts, thereby film is directly by second surface support forward.Signal source also is applied to second on front surface by means of variable voltage.
Static emitter film 365 need comprise a conductive layer with the noncontact relation with corresponding the one the second foam films, so as to make film can with a kind of push-pull relationship with first and second forward surface electrical capacitive ground respond variable voltage.May require an insulating part with respect to second foam element.
Several configurations of emitter film are possible.For example, Figure 22 represents to press from both sides first and second foam elements 370 and 371 of film-holding piece.In this case, the static emitter film is made up of the two boards at least 372 and 373 of the non-conductive emitter film that comprises a conductive surface 374 and 375 respectively.Non-conductive emitter film is provided at the insulation of conductive layer and corresponding first and second between front surface.Relative conductive surface 374 and 375 is bonded together to form a monolithic conductive layer.
Figure 23 and 24 expressions are clamped in a plurality of emitter film 332 between foam or the general strutting piece 330,331,340,341 and 342 use.Each other emitter film is added about 3db output on the ultrasonic signal of emission to.Obviously, in this Multiple Combination pattern, can adopt various configurations.
And an alternative embodiment of the invention relates to the planar magnetic film barrier film that uses magnetic force to create a parameter transducer.Figure 25 describes a kind of configuration of the present invention.Specifically, it comprises a ultrasound emission body that has the wide frequency range ability by means of the big diaphragm displacement of comparing with the motion of the name of typical electrostatic barrier film.Really, orthogonal translation (barrier film moves to crest from the crest that extends to complete punctured position fully) can be greatly to 1-2mm.This compares highly beneficial with 0.1 to 3 micron range of movement for rigidity transducer emitter surface.
The benefit that is used for magnetic barrier film extension motion of the present invention comprises enlarging markedly of ultrasonic harmony output amplitude for a parametric arrays.Enhancing sound output of the present invention can realize by using the magnetic field that is produced by a magnetic core spare 426.This magnetic core can be a permanent magnet or a kind of composition that is suitable for the electromagnetism purposes.Such material can be flexible or rigidity, depends on the configuration of loudspeaker array.For example, a surface plate will be created in the sound column that has surprising ejaculation ability on the long distance.By make by flexible ferromagnetic material with the similar bent support magnetic core of dismountable magnet that is installed on utensil etc., can form emitter barrier film with support bends.This curved configuration is provided for penetrating the bigger dispersion pattern of sound, and also can realize the detection for the directed movement of emission sound.This can trigger along the transfer voice realization of a linear order of emitter elements (or conductive coil) 430 by order, and emitter elements 430 is arranged along barrier film 434.When these elements were being dispersed in the configuration to external radiation, the audience felt that source image has the physical component of motion in the direction.
Basic embodiment referring now to Figure 25 will notice, permanent, rigidity magnetic core or plate 426 are with the support that acts on flexible emitter barrier film 434.This permanent magnet 426 is in the mode of the permanent magnet that is similar to acoustic speaker, as the main device operation in one first magnetic field that is used for setting up adjacent magnetic core spare.Yet, in this case, do not receive the telescopic magnetic core or the recess of stator component.But magnetic core 426 is one and sets up the plane body of a uniform magnetic field along its length, is provided for being based upon the essential reaction force of the variable magnetic field in the barrier film 434 thus.
The movable barrier film 434 that shows stretches along magnetic core spare 426, and leaves magnetic core spare and move a short separating distance, with provide barrier film with respect to the expectation scope of magnetic core spare orthogonal translation and one of magnetic field by force partly in.Typically, this barrier film 434 comprises a Mylar or other films firm, lightweight polymer.Multiple such material has been used in electrostatic loudspeaker or the industry of ultrasound emission body.
The increase displacement of barrier film 434 is by being arranged at least one on the movable barrier film, little quality, plane, conductive coil (or emitter elements 430) realization.When the electric current coils was conducted, thin conductive coil 430 was created a magnetic field.The present inventor has been found that the power in magnetic field can realize in the voice coil loudspeaker voice coil on being arranged in planar film, produces the benefit that the displacement of barrier film 434 basically far surpasses the prior art electrostatic loudspeaker systems.This electric current supplies to coil 430 by first and second contacts 438 and 442 that are connected on the power supply.First contact 438 is connected on the end of coil 430, and is general in a side shared with coil itself.Second contact 442 is arranged in the opposite side of coil 430, and the electrical isolation with first contact 438 is provided thus.The embodiment that shows represents that film (or barrier film 434) is passed in second contact 442 and extends to along the apparent surface of film to be used for closure and to be used for a pickup point of the circuit that electric current flows.The additive method of corresponding first and second contacts of electrical isolation is obvious to those skilled in the art.
As shown in Figure 26, the another one of magnetic core spare can select embodiment can comprise the rigid plate 446 that at least one is formed by non magnetic composition, and one surface comprises at least one the relative conductive coil 450 that structurally is similar to the conductive coil of describing for barrier film 430.A kind of like this coil comprises and is used for making electric current first and second contacts 454 and 458 of relative conductive coil 450 of flowing through, and sets up second magnetic field that needs thus.This at least one relative conductive coil 450 is positioned on the rigid plate, with the position arranged side by side of at least one conductive coil 430 on vibration or movable barrier film 434 in, make the relative conductive coil 450 of at least one conductive coil 430 produce corresponding magnetic field, to produce from the compressional wave of barrier film emission from interactional each coil with at least one.
Equally, first contact 454 is positioned at a side of barrier film, and second contact 458 is positioned on the opposite side of barrier film.This can be the form of the single coil that shows among Figure 26, perhaps as a plurality of conductive coils of the barrier film equidistant from distance described in Figure 25.Be ideally, conductive coil 430 and 450 and column position arrange with multirow so that the uniformity in magnetic field and the coil amount maximum used.
A kind of plane magnetic of selecting that Figure 27 describes a kind of parameter loud speaker disposes.Specifically, it comprises: a magnetic core spare 460 that is used for providing rigid support, and at least one conductive coil 462 is connected on the magnetic core; With a barrier film 468, comprise the conductive coil 466 of a response by the magnetic field of conductive coil generation.Operating principle in this structure is based upon conducting ring generation electric current when by magnetic field and flows in essence.Specifically, when conducting ring experience magnetic field gradient, electric current with set up one with this ring of flowing through by the orientation of the opposite magnetic moment of the magnetic force of coil generation.This phenomenon causes the repulsion between coil and conducting ring.Many physics students observed this repulsive force in the performance of classroom strength, it is mapped to aerial 20 to 30 feet to the aluminium environment-development.Interaction energy between coil 462 and ring 466 is described by two physics principles of so-called Faraday's law of induction and Lenz's law.See the Fundamentals of Physics (foundation of physics) of Halliday and Resnich, second edition, the 34th chapter.
The present inventor is used for producing a kind of variable extension to these principles and shrinks to produce a loud speaker barrier film of wishing the sequence compressional wave.By an arrayed applications of conducting ring in one such as Mylar
TMOr Kapton
TMDeng and so on elasticity, flexible film, and this film is superimposed upon on the respective array of conductive coil, might bounce back into a kind of tension force bias state to film, to produce a kind of controlled barrier film vibration through the Modulation and Amplitude Modulation of the electric current by coil.The elasticity of film allows it to be withdrawn into the biasing resting position that film wherein is in stressed a little extension state.This biasing, resting position are by in alternating current basis that keeps the repulsive force minimum value between coil and the ring or carrier signal generation.
Continuous output with the variable alternating current of information modulation can convert the frequency of representing this information and amplitude to represent sound physical compression ripple.Thereby the conventional modulated carrier such as sine wave can be used for wishing that audio output signal supplies to the magnetic film emitter of description to one, to produce a kind of speaker system efficiently.
This system also provides a kind of unique capacity as the ultrasound emission body with wide frequency range capacity, compares with the name motion of typical electrostatic barrier film to have than the macromesenterium displacement.Yet, the magnetic repulsion film of present embodiment provide one can be greatly to several millimeters orthogonal translation (crest of barrier film from full extension to the resting position of setovering moves to crest).Therefore, diaphragm displacement of the present invention preferably and rigidity transducer emitter surface or even the less range of movement of the deflectable diaphragm of conventional static emitter equally matched.
This increase displacement is possible, because the distance that the effective range in magnetic field is extended than the short distance power relevant with electrostatic field is big.Therefore may only extend in several microns scope although be noted that the effective force of static emitter, magnetic barrier film of the present invention has and multiply by greater than 100 factor in a big way.Therefore, the emitter barrier film can be repelled or attract to the use of magnetic force on significantly bigger path.
The benefit that is used for the extension campaign of big magnetic barrier film of the present invention comprises that with the bimorph transducer can compare system and compare, and for parameter or acoustics mixing array, the amplitude that sound is exported enlarges markedly.And, with regard to the film emitter, to compare with the rigidity transducer, the near-linear response is stronger.These are to make the field of parameter loud speaker have the remarkable factor of the commercial exploitation rate of raising, and this utilance is subjected to some restrictions up to now always.
An alternative embodiment of the invention shows in Figure 28 of a static emitter 510 of expression.Specifically, this emitter comprises a rigid substrate 511 that can carry a voltage, a kind of on-chip thin-film dielectric material 512, and conductive layer 513 that is positioned on the dielectric film 512 of being suspended on.Usually, dielectric material 512 (as Mylar) scribbles one deck conducting film 513 on the surface thereon.Therefore, basic emitter 510 is exercisable for substrate and metal coat Mylar film only.
As shown in Figure 29, this most preferred embodiment also comprises an air chamber 514 that is arranged in below the substrate, and the passage aisle 515 that is used in the air-flow between chamber and areola 516 is formed on the upper surface place of substrate.
With reference to Figure 28 and 29, rigid substrate 511 can be formed by the material that is applied in the general static emitter in prior art.These materials comprise moulded plastic, timber, be coated in silicon wafer or the upside that upside has a conductive surface handles to comprise the simple electric conducting material of requirement cavity.The cutaway view of this structure is provided among Figure 29.The ductule 515 that each cavity 516 rigid substrate 511 of expression has from air chamber 514 to the upper surface that is formed on substrate is communicated with.This chamber 514 provides the more uniform tension that strides across dielectric film 512, because shared pressure links with chamber and each is connected cavity 516 as the operation of a shared pressure chamber.This chamber 514 also can stand negative pressure, so as film 512 mechanically to be biased to recessed cup-shaped 520, as shown in Figure 28.The use of bias pressure is avoided using relevant well-known problems with bias voltage.
This recessed cup 520 becomes the vibration emitter elements that one of response can make the variable signal input of the ultrasonic carrier signal propagation that has sideband just, and these sidebands mix to produce an audible sounds post 525.The invention provides the even recessed cup that is called emitter elements, this recessed cup is kept apart to produce a conscientious even value tuning, resonance frequency with the effect of adjacent transmission body member basically.Be formed on cavity 516 in the substrate 511 preferably with uniform-dimension and the accurate mold pressing of profile.This allows the more accurate uniformity in respective cavities 516, to produce the more resonance frequency of fine tuning.
Just the embodiment of the invention of describing provides the surprising result who resembles the parameter loudspeaker device.It is provided at and produces the array of cavities that audio frequency is exported in the ultrasonic post of emission respectively and indirectly.The generation of the ultrasonic mixing in each of these posts of tuning emitter elements emission, the actual reinforcement in sound pressure level (SPL) from a distance of emitter.As shown in Figure 29, each emitter portion 520 is propagated the sound post 525 of a high orientation.By provide evenly be tuned to wish an array of a plurality of emissions sector 520 of resonance frequency, finish the simulation before the homogeneous wave, have recently from the much bigger amplitude that comprises the static barrier film of the monofilm that can on the univoltage source, operate.Evenly the use of cavity also is an advantage that is better than prior art: be reproducible in the mill, and be predictable therefore.Prior art need conscientiously be checked the quality control of each emitter substrate, but to guarantee to produce the operating surface of pit or cavity.This is necessary, because the result that the difference of machinery and chemical etching technical basis environment changes.On the contrary, present embodiment can be implemented by means of the conventional mold pressing or the course of processing.
Another embodiment of a kind of ultrasonic electrostatic transducer is illustrated among Figure 30.The cutaway view of a hemisphere electrostatic transducer 551 is expressed as anchoring on the pedestal 552.Figure 30 is the cross section of Figure 31 along arrow 570.Two cylindrical ripple stators 556 are created a kind of hemispherical shape, and an on-plane surface barrier film 560 is arranged between two relative stator.In addition, a kind of supporting construction 553 is extended along the inboard of hemisphere or along the longitudinal axis of hemisphere.Should be realized that stator has hole or aperture, transparent thereby they are acoustics, and allow ultrasonic wave to pass through.Barrier film is setovered by a bias voltage 550, and applies sound signal 554 to produce a ultrasonic compressional wave.Buffering or insulating barrier 558 are included in the stator, thereby barrier film does not directly contact the conductive layer on the stator, and avoids contacting with other distortions of stator.
Figure 31 is a kind of stereogram of hemisphere electrostatic loudspeaker.Because the hemisphere essence of this embodiment is launched in 180 degree with multiaxis through the sound that stator 556 sends.The complete ball embodiment of this embodiment is illustrated among Figure 32.The figure shows the stereogram of spherical embodiment 580 of the combination that is two hemisphere shown in Figure 31.This spherical arrangement allows ultrasonic/sonic wave 590 might produce on the direction in institute.The pedestal 584 that can comprise an electric component connects two hemisphere.An electric component also can be fixed for a short time as to be enough to be included in the hemisphere size, and can use a much smaller pedestal 584.Certainly, can implement other base shape such as circle.A bias voltage is applied to is included on the semi-sphere diaphragm by importing 588, and apply sound signal through 586 then.
Obviously, according to the abovementioned embodiments of the present invention, numerous variations and combination can be produced by those skilled in the art.Thereby, be appreciated that the present invention is not limited by specific examples described above.
Claims (72)
1. one kind is used for according to improving the method for parameter audio frequency output as the reciprocation of airborne a plurality of supersonic frequencies of nonlinear dielectric, and described method comprises step:
A) produce an electronic signal that comprises at least two ultrasonic signals, these two ultrasonic signals have the poor of the value that drops in the sound frequency rate scope;
B) electronic signal is sent to an emitter film transducer diaphragm that has an array of the arc emitter portion that is formed in the film;
C) with an actuator of a parameter loud speaker in phase electricity-machine move the array of arc emitter portion; And
D) at least two ultrasonic signals are transmitted into the air from barrier film, as in air, interacting to produce the ultrasonic compressional wave of parameter audio frequency output.
2. method according to claim 1, wherein step c) comprises a more specifically step that moves emitter portion with a kind of controlled way, so that make saturated minimum, reduce part as distortion for the parameter loud speaker in corresponding arc emitter portion place surrounding air.
3. method according to claim 1, wherein step d) comprises the more specifically step of the emitter portion emission supersonic frequency from the collimation configuration.
4. method according to claim 1, wherein step b) comprises the more specifically step that electronic signal is sent to a piezoelectric film barrier film.
5. method according to claim 4, wherein step b) comprises the more specifically step that electronic signal is sent to the piezoelectric film barrier film of an array that has circle, an arc emitter portion.
6. method according to claim 4, wherein step b) comprises the more specifically step that electronic signal is sent to the piezoelectric film barrier film of an array that has elongated, an arc emitter portion.
7. method according to claim 4, wherein step b) comprises electronic signal is sent to a more specifically step that has with the piezoelectric film barrier film of the array of elongated, the tunnel-shaped groove of substantially parallel relation location.
8. method according to claim 4, wherein step b) comprises electronic signal is sent to a more specifically step with piezoelectric film barrier film of rectification sinusoidal form configuration.
9. method according to claim 4, wherein step b) comprises the more specifically step that electronic signal is sent to a piezoelectric film barrier film, this piezoelectric film barrier film is being supported by a back plate with basic planar configuration.
10. method according to claim 4, wherein step b) comprises the more specifically step that electronic signal is sent to a piezoelectric film barrier film, this piezoelectric film barrier film has a kind of basic planar configuration except that the arc emitter portion of extending a little from planar configuration.
11. method according to claim 1 further comprises the step of selecting a transducer diaphragm, this transducer diaphragm has than the big emitter size of wavelength in the supersonic frequency at its minimum place.
12. method according to claim 1 further comprises the step of selecting a transducer diaphragm, this transducer diaphragm has than the emitter size big ten times of the wavelength of the supersonic frequency at its minimum place.
13. method according to claim 1 further comprises the step of selecting a transducer diaphragm, this transducer diaphragm has a kind of emission for parameter output and produces convex bending in a kind of stray radiation whole pattern.
14. method according to claim 1 further comprises the step of selecting a transducer diaphragm, this transducer diaphragm has a kind of emission for parameter output and produces the bending of a kind of focused radiation whole pattern concave.
15. method according to claim 14, further comprise step: make the rate of decay, relevant with the radius of the concave bending of barrier film that absorbs the ultrasound emission that produces according to the ultrasonic energy of frequency values in the air, described radius is chosen to compensate ultrasonic energy losses at least by ultrasound emission being focused into a convergence supersonic beam.
16. method according to claim 1 further comprises the step that plate after transducer diaphragm and the support is separated the quarter-wave distance of selecting frequency.
17. method according to claim 16, wherein selecting frequency is carrier frequency.
18. method according to claim 4, further comprise the step that the transducer diaphragm that ripples is provided, this barrier film comprises a whole diaphragm of the concave ripple of the tight spacing with the close-packed array of being arranged in, and this array produces substantially all radiation pattern of even homology for the emission of the parameter output that strides across membrane surface.
19. method according to claim 4, wherein step b) comprises the more specifically step that electronic signal is sent to plate after, this back plate has a kind of configuration that comprises the opening of aiming at arc emitter portion, and has enough degree of depth to allow the free vibration of arch emitter portion.
20. one kind is used for according to improving the method for parameter audio frequency output as the interaction of airborne a plurality of supersonic frequencies of nonlinear dielectric, the method comprising the steps of:
A) produce an electronic signal that comprises at least two ultrasonic signals, these two ultrasonic signals have the poor of the value that drops in the sound frequency rate scope;
B) simultaneously electronic signal is sent to an array that is formed on an arc emitter portion in the electroacoustic film transducer barrier film commonly used;
C) mobile in a controlled manner emitter portion is so that make saturated minimum in corresponding arc emitter portion place surrounding air, as the part that reduces for the parameter loudspeaker distortions;
D) with an actuator of a parameter loud speaker in phase electricity-machine move the array of arc emitter portion;
E) at least two ultrasonic signals are transmitted into the air from barrier film, as ultrasonic compressional wave; And
F) interact aerial ultrasonic compressional wave to produce the output of parameter audio frequency.
21. method according to claim 20, wherein step c) comprises that this maximum electron signal limit is by making the continuous distortion that prevents audio frequency output in the saturated minimum of corresponding arc emitter portion place surrounding air according to the more specifically step of a kind of weighting relation between the size of sound pressure level, supersonic frequency and emitter portion with a maximum electron signal limit restriction electronic signal.
22. method according to claim 21, wherein step c) comprises that a sound pressure level for all emitter portion is restricted to the more specifically step less than 140db.
23. one kind is used for according to producing the loudspeaker device of parameter audio frequency output as the reciprocation of airborne a plurality of supersonic frequencies of nonlinear dielectric, described device comprises:
A) parameter signals produces system, comprise a source of ultrasound signal, sound signal source, and one be connected to and be used on the ultrasonic harmony frequency source signal ultrasonic and sound signal are mixed so that produce the modulation device of the electronic signal of a generation, the electronic signal of this generation comprises that the difference of value drops at least two interior ultrasonic signals of a sound frequency rate scope;
B) electroacoustic film transducer barrier film has an array of the arc emitter portion that is connected in the parameter signals generation system; And
C) supporting construction is connected on the barrier film and has cavity with the array alignment of arc emitter portion, is used for location and stablize arc emitter portion, so that realize the mechanical displacement of an actuator homophase of an arc emitter portion and a parameter loud speaker.
24. the array of arc emitter portion is wherein aimed at and supported to device according to claim 23, so that propagate the collimated wave beam of the ultrasound emission of the enhancing generation that is used for parameter output.
25. device according to claim 23, wherein transducer comprises a piezoelectric film barrier film as the electroacoustic transducer barrier film.
26. device according to claim 23, wherein arc emitter portion has a kind of circular configuration.
27. device according to claim 26, wherein the piezoelectric film barrier film comprises that running through arc emitter portion produces the isotropic nature that even electricity-machine responds.
28. device according to claim 23, wherein arc emitter portion have a kind of elongated configuration that has slender axles.
29. device according to claim 28, wherein the piezoelectric film barrier film comprises the anisotropic properties that produces big electricity-machine response perpendicular to the slender axles of arc emitter portion.
30. device according to claim 28, advance one and comprise a cabin that is connected on the emitter portion, wherein this cabin remain on different with ambient pressure and have sufficient intensity barrier film be moved into the equally crooked hope pressure of an emitter portion under.
31. device according to claim 30 wishes that wherein pressure comprises and the equal negative pressure level of ambient pressure, moves barrier film in the aligned with cavities to thus.
32. device according to claim 30 further comprises the device that is connected to the permanent seal that is used to have the cabin of wishing pressure on the cabin.
33. one kind is used for according to improving the method for parameter audio frequency output as the interaction of airborne a plurality of supersonic frequencies of nonlinear dielectric, the method comprising the steps of:
A) produce an electronic signal that comprises at least two ultrasonic signals, these two ultrasonic signals comprise a ultrasonic carrier signal and at least one other ultrasonic signal, have one and drop on the poor of a value in the sound frequency rate scope with respect to carrier signal;
B) electronic signal is sent to an array that is formed on an arc emitter portion in the electroacoustic film transducer barrier film commonly used, this barrier film has a propagation main shaft;
C) with the array of general concave form configuration emitter portion, so that so that the convergence of emission ultrasonic beam to be provided from least one neighboring of array with respect to a predetermined convergence angle propagating main shaft;
D) with an actuator of a parameter loud speaker in phase electricity-machine move the array of arc emitter portion;
E) at least two ultrasonic signals are transmitted into the air from barrier film, as ultrasonic compressional wave; And
(f) interact aerial ultrasonic compressional wave to produce the output of parameter audio frequency.
34. method according to claim 33, the step that wherein disposes array comprise according to the needs of the energy loss compensation by the ultrasonic energy that absorbs in the air are selected convergence angle.
35. method according to claim 33, wherein configuration step comprises that selection is along propagating the angle of main shaft interpolation with the convergence of the ultrasonic energy that is absorbed the energy loss approximate match that generates by the ultrasonic energy that passes through air.
36. method according to claim 35, wherein configuration step comprises the other step of calculating ultrasonic energy losses according to the convergence angle of selecting to select the calculating energy of location to lose approximate match with the space.
37. method according to claim 35 is included in respect to the more specifically step of selecting a convergence angle in the scope of propagating main shaft 0.1 to 5 degree.
38. method according to claim 35 comprises the more specifically step of selection with respect to convergence angles of propagation main shaft 3 degree.
39. one kind is used for from entering the emitter that airborne ultrasound emission produces audio frequency output, described emitter comprises a flexible piezoelectric membrane, this film has a plurality of arc emitter configuration that strides across a surface arrangement of film and be configured to respond the electric signal corresponding with supersonic frequency, enters airborne ultrasonic compressional wave so that produce.
40. according to the described emitter of claim 39, further comprise a supporting bracket that is connected on the film, be used for by means of arc emitter configuration support film, so that emission enters airborne ultrasonic compressional wave.
41. according to the described emitter of claim 39, wherein supporting bracket comprises the aperture of aiming at arc emitter configuration, these apertures allow arc configuration expansion or shrink, and apply the bending of voltage modifications film on aperture so that respond one.
42. according to the described emitter of claim 40, before wherein supporting bracket and film are configured to produce the homogeneous wave of ultrasonic compressional wave.
43. according to the described emitter of claim 42, wherein the arc configuration of film is aimed at, so that launch compressional wave from film along parallel axes.
44. according to the described emitter of claim 41, the shared dimensional configurations of aperture wherein, these apertures are aimed at the emitter configuration of film on being supported on supporting bracket.
45. according to the described emitter of claim 39, wherein piezoelectric film comprises the electric contact of the individual signals that is used to receive all emitter configurations that impose on film, thereby makes harmonic wave and phase distortion minimum in the ultrasound emission.
46. according to the described emitter of claim 39, wherein the emitter of film is configured in size, is uniform on curvature and the composition.
47. according to the described emitter of claim 39, wherein emitter is configured to ojosa and strides across the film surface arrangement.
48. according to the described emitter of claim 40, wherein aperture allows the motion of film.
49. according to the described emitter of claim 39, wherein piezoelectric film is made by polyvinylidene fluoride, has isotropic nature.
50. according to the described emitter of claim 39, wherein piezoelectric film is made by the composition with each different in nature character.
51. a parameter loud speaker comprises a supporting bracket and a thin piezoelectric film, thin piezoelectric film has and is used for the emission of ultrasonic compressional wave is entered a ultrasound emission volume array in the non-linear air dielectric.
52. according to the described parameter loud speaker of claim 51, wherein the ultrasound emission volume array comprises an array of the arc emitter cells that strides across the piezoelectric film layout.
53. according to the described parameter loud speaker of claim 52, wherein piezoelectric film is made up of polyvinylidene fluoride.
54. one kind is used for producing the loudspeaker device of parameter audio frequency output with generation sound in as the air of nonlinear dielectric or infrasound signal according to the reciprocation of a plurality of supersonic frequencies, described device comprises:
A magnetic core spare has the device that is used for setting up first magnetic field adjacent with magnetic core spare;
A movable barrier film stretches along magnetic core spare, and moves a short separating distance from magnetic core spare, with provide a barrier film with respect to the orthogonal translation of magnetic core spare the expectation scope and one of first magnetic field by force partly in;
At least one, little quality, plane, the conductive electric wire circle, be arranged on the movable barrier film, and comprise first and second contacts of the opposite end that is used for making the electric current flowing through coil; And
Be used for variable current flowed and be applied at least one coil so that produce the device in one second magnetic field, this second magnetic field changeably with first magnetic field interaction so that attract with hope frequency and repel barrier film for the generation that can be adjusted to a series of compressional waves that comprise a ultrasonic frequency range.
55. according to the described device of claim 54, wherein permanent magnet comprises that a size is a bit larger tham the magnetic material rigid plate of size of the movable emitting surface of emitter device.
56. according to the described device of claim 54, here magnetic core spare comprises the rigid plate that a non magnetic composition forms, a surface of this plate comprises at least one relative conductive coil, and this coil has can make flow through first and second contacts of relative conductive coil of electric current.
57. according to the described device of claim 56, at least one relative conductive coil is positioned on the rigid plate, with movable barrier film at least one conductive coil position arranged side by side in, make the relative conductive coil of at least one conductive coil produce corresponding magnetic field, to produce compressional wave from interactional each coil with at least one.
58. according to the described device of claim 54, its septation comprises a film, described at least one coil arrangement is in a side of film.
59. according to the described device of claim 58, wherein film is striden across the polymer that its surface has isotropic nature and is formed by a kind of, to provide applying the uniform response of tension force.
60. according to the described device of claim 54, wherein at least one conductive coil comprises a plurality of voice coil loudspeaker voice coils, each voice coil loudspeaker voice coil comprises that contact with barrier film one supports periphery, and provides and be used at the displacement of the barrier film at each coil place and the device that adjacent windings is isolated substantially.
61. according to the described device of claim 60, wherein be used for the support periphery of retarder and comprise a kind of grid configuration that is limited in a plurality of aperture displacement cavitys of the magnetic core spare surface adjacent with barrier film, each cavity is aimed at one of conductive coil.
62. according to the described device of claim 61, the device that wherein is used to provide first magnetic field comprises that a variable current at least one coil at magnetic core place flows, thisly flow and apply the variable current that produces second magnetic field and have the phase inversion relation, increase the attraction and the repulsion of barrier film thus, can be adjusted to a series of compressional waves that comprise ultrasonic frequency range so that produce.
63. one kind is used for producing the output of parameter audio frequency according to the reciprocation of a plurality of supersonic frequencies and compares the method with the ability that is used for sizable diaphragm displacement with generation sound in as the air of nonlinear dielectric or infrasound signal with the less motion of typical electrostatic diaphragm movement, described method comprises step:
(a) provide and one first an adjacent magnetic field of support magnetic core spare;
(b) at least one conductive coil be applied to along magnetic core spare extend and on the movable barrier film of a short separating distance of magnetic core spare, with provide barrier film with respect to the expectation scope of magnetic core spare orthogonal translation and one of first magnetic field by force partly in; And
(c) variable current is supplied to be used for producing at least one coil in one second magnetic field, this second magnetic field and first magnetic field interaction are so that can be adjusted to a series of compressional waves of being included in the ultrasonic frequency range and to attract with hope frequency and repel barrier film in order to produce.
64. one kind is used for producing the wide frequency range ability with sizable diaphragm displacement is compared in the output of parameter audio frequency with the typical electrostatic diaphragm movement with generation sound in as the air of nonlinear dielectric or infrasound signal ultrasound emission body device according to the reciprocation of a plurality of supersonic frequencies, described device comprises:
A magnetic core spare has the device that is used for setting up a variable magnetic field adjacent with magnetic core spare;
A movable barrier film is arranged along magnetic core spare with tension force, and from short separating distance of magnetic core spare, with provide barrier film with respect to of magnetic core spare estimate scope orthogonal translation and one of variable magnetic field by force partly in; And
At least one conducting ring, be arranged on the movable barrier film, be used for making electric current to be flowing in producing one oppositely, in the orientation of phase anti-magnetic, this magnetic force is repelled under hope frequency by the variable magnetic field of magnetic core spare, can be adjusted to a series of compressional waves that comprise ultrasonic frequency range so that produce.
65. according to the described device of claim 64, wherein magnetic core spare is made up of an electromagnet.
66. according to the described device of claim 65, wherein rigid plate comprises one flat plate, make even variable magnetic field along with a surface of the tightest adjacent plate of movable barrier film.
67. according to the described device of claim 64, wherein magnetic core spare comprises a rigid plate that is formed by non magnetic composition, a surface of plate comprises at least one the relative conductive coil that has first and second terminal contacts, so that make the electric current conductive coil of flowing through.
68. according to the described device of claim 67, wherein at least one conductive coil is positioned on the rigid plate, with movable barrier film at least one conducting ring position arranged side by side in, can make the relative conducting ring of at least one conductive coil cause relative magnetic field interaction, to produce compressional wave with at least one.
69. according to the described device of claim 64, its septation comprises a film, described at least one coil arrangement is in a side of film.
70. according to the described device of claim 67, wherein film is striden across the polymer that its surface has isotropic elastic property and is formed by a kind of, to provide applying the uniform response of tension force.
71. a sound mix that is used for by ultrasound emission becomes the ultrasound emission body device of audio frequency output to transform electric, described device comprises:
A rigidity magnetic core spare has the upper surface of an array of a cavity that comprises preliminary dimension, and comprises that the device of the raising that is used at least one resonance frequency, this resonance frequency can be used as the carrier frequency operation in a ultrasonic frequency range;
Be used for producing the device of an electrostatic field at the upper surface place of magnetic core spare;
Elasticity, dielectric barrier film, with tension force along upper surface and stride across the arrangement of cavities of magnetic core spare, with an expectation scope of the emission sector of barrier film that the cavity top that is positioned at magnetic core spare is provided or just imitating displacement, and in strong part of electrostatic field;
A kind of conducting medium is coated on the surface of barrier film, and with magnetic core spare electrical isolation; And
Modulating device, be connected on the conducting medium, be used for making a variable electrostatic field to be applied on the barrier film, the electrostatic field of this barrier film and magnetic core spare interacts, wish a series of ultrasonic compressional wave that sends from the emission sector of barrier film in the ultrasonic frequency range to be created in, this frequency range is propagated in a kind of non-linear air dielectric the ultrasonic compression wave system of demodulation and be listed as to produce audio frequency and exports.
72. according to the described device of claim 71, wherein magnetic core spare comprises an array of cavities with the configuration of even concave, these configurations general be tuned to a common resonant frequency.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US15944298A | 1998-09-24 | 1998-09-24 | |
| US09/159,442 | 1998-09-24 |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB998126802A Division CN1181704C (en) | 1998-09-24 | 1999-08-26 | Parametric loudspeaker with electro-acoustical disphragm transducer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1620195A true CN1620195A (en) | 2005-05-25 |
Family
ID=22572623
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB998126802A Expired - Fee Related CN1181704C (en) | 1998-09-24 | 1999-08-26 | Parametric loudspeaker with electro-acoustical disphragm transducer |
| CN 200410087797 Pending CN1620195A (en) | 1998-09-24 | 1999-08-26 | Parametric loudspeaker with electro-acoustical disphragm transducer |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB998126802A Expired - Fee Related CN1181704C (en) | 1998-09-24 | 1999-08-26 | Parametric loudspeaker with electro-acoustical disphragm transducer |
Country Status (8)
| Country | Link |
|---|---|
| EP (1) | EP1123634A4 (en) |
| JP (1) | JP2002526004A (en) |
| CN (2) | CN1181704C (en) |
| AU (1) | AU5902099A (en) |
| BR (1) | BR9913954A (en) |
| CA (1) | CA2345339A1 (en) |
| HK (1) | HK1041763A1 (en) |
| WO (1) | WO2000018182A1 (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102082551A (en) * | 2010-12-16 | 2011-06-01 | 瑞声声学科技(深圳)有限公司 | Audio-frequency playback system of parametric acoustic array and modulating method thereof |
| CN105378957A (en) * | 2013-05-08 | 2016-03-02 | 达尔豪西大学 | Acoustic transmitter and implantable receiver |
| CN107872757A (en) * | 2016-09-23 | 2018-04-03 | 苹果公司 | Extend through the loudspeaker back cavity of loudspeaker diaphragms |
| US11256338B2 (en) | 2014-09-30 | 2022-02-22 | Apple Inc. | Voice-controlled electronic device |
| US11290805B2 (en) | 2014-09-30 | 2022-03-29 | Apple Inc. | Loudspeaker with reduced audio coloration caused by reflections from a surface |
Families Citing this family (31)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20050100181A1 (en) * | 1998-09-24 | 2005-05-12 | Particle Measuring Systems, Inc. | Parametric transducer having an emitter film |
| EP1444861B1 (en) * | 2001-10-09 | 2020-03-18 | Frank Joseph Pompei | Ultrasonic transducer for parametric array |
| CN1754405B (en) * | 2003-02-27 | 2010-04-14 | Nxp股份有限公司 | Generating device for generating a useful stream of a medium, in particular for generating sound |
| JP4438444B2 (en) | 2004-02-19 | 2010-03-24 | セイコーエプソン株式会社 | Projector equipped with ultrasonic speaker and method for displaying sound reproduction range in projector |
| JP2005354582A (en) | 2004-06-14 | 2005-12-22 | Seiko Epson Corp | Ultrasonic transducer and ultrasonic speaker employing it |
| JP4103877B2 (en) * | 2004-09-22 | 2008-06-18 | セイコーエプソン株式会社 | Electrostatic ultrasonic transducer and ultrasonic speaker |
| KR100689876B1 (en) * | 2004-12-20 | 2007-03-09 | 삼성전자주식회사 | Sound reproducing system by transfering and reproducing acoustc signal with ultrasonic |
| JP2007028205A (en) * | 2005-07-15 | 2007-02-01 | Sony Corp | Electroacoustic transducer and method of forming diaphragm thereof |
| CN101558660B (en) * | 2006-05-22 | 2013-08-21 | 奥迪欧彼塞尔斯有限公司 | Apparatus and methods for generating pressure waves |
| KR101000291B1 (en) * | 2007-12-20 | 2010-12-13 | 한국전자통신연구원 | Apparatus and method for transmitting sound through nonlinear media |
| JP5900348B2 (en) * | 2010-12-20 | 2016-04-06 | 日本電気株式会社 | Oscillator and electronic device |
| US9306148B2 (en) | 2010-12-20 | 2016-04-05 | Nec Corporation | Oscillator device and electronic apparatus |
| CN103220606B (en) * | 2012-01-20 | 2015-10-21 | 中华大学 | Electroacoustic transducer and manufacture method thereof |
| WO2013188514A2 (en) | 2012-06-12 | 2013-12-19 | Frank Joseph Pompei | Ultrasonic transducer |
| US9002043B2 (en) | 2013-02-20 | 2015-04-07 | Turtle Beach Corporation | Parametric transducer and related methods |
| US8718297B1 (en) * | 2013-02-20 | 2014-05-06 | Parametric Sound Corporation | Parametric transducer and related methods |
| CN103152659A (en) * | 2013-02-26 | 2013-06-12 | 广东欧珀移动通信有限公司 | Piezoelectric ceramic speaker protective device and mobile terminal |
| US9332344B2 (en) | 2013-06-13 | 2016-05-03 | Turtle Beach Corporation | Self-bias emitter circuit |
| JP6255994B2 (en) * | 2013-06-27 | 2018-01-10 | 株式会社リコー | Energy converter |
| EP3013736A1 (en) * | 2013-06-27 | 2016-05-04 | MiniPumps, LLC | Method of making a corrugated deflection diaphragm |
| US9976713B2 (en) | 2013-07-05 | 2018-05-22 | Qualcomm Incorporated | Apparatus and method for providing a frequency response for audio signals |
| RU2571588C2 (en) * | 2014-07-24 | 2015-12-20 | Владимир Анатольевич Ефремов | Electronic device for automatic translation of oral speech from one language to another |
| JP6365164B2 (en) * | 2014-09-18 | 2018-08-01 | 株式会社村田製作所 | Vibration device and tactile presentation device |
| CN104688192B (en) * | 2015-03-31 | 2017-06-06 | 西安交通大学 | Audio sound source based on difference frequency ultrasound is produced and air flue characteristic test method and system |
| WO2017079435A1 (en) * | 2015-11-03 | 2017-05-11 | Nrg Systems, Inc. | Techniques for providing a broad-band ultrasonic transducer device using a plurality of narrow-band transducer arrays and a method of wildlife deterrence using same |
| TWI626854B (en) * | 2016-11-24 | 2018-06-11 | 財團法人金屬工業研究發展中心 | Electret thin film and manufacturing method thereof |
| WO2019199978A1 (en) * | 2018-04-10 | 2019-10-17 | Nrg Systems, Inc. | Techniques for providing acoustic impedance matching for a broad-band ultrasonic transducer device and a method of wildlife deterrence using same |
| CN109168108B (en) * | 2018-10-24 | 2021-03-02 | 维沃移动通信有限公司 | Amplitude adjusting method and device for electroacoustic device and mobile terminal |
| CN112004176B (en) * | 2020-08-19 | 2021-05-07 | 厦门大学 | Underwater sound transducer for realizing underwater broadband collimation |
| US20220183659A1 (en) * | 2020-12-15 | 2022-06-16 | Sonicedge Ltd. | Earphone Driver And Applications |
| CN117560607B (en) * | 2023-12-29 | 2024-04-05 | 汉得利（常州）电子股份有限公司 | Ultrasonic loudspeaker |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4056742A (en) * | 1976-04-30 | 1977-11-01 | Tibbetts Industries, Inc. | Transducer having piezoelectric film arranged with alternating curvatures |
| US4242541A (en) * | 1977-12-22 | 1980-12-30 | Olympus Optical Co., Ltd. | Composite type acoustic transducer |
| US4276449A (en) * | 1978-06-01 | 1981-06-30 | Tadashi Sawafuji | Speaker or microphone having corrugated diaphragm with conductors thereon |
| US4322877A (en) * | 1978-09-20 | 1982-04-06 | Minnesota Mining And Manufacturing Company | Method of making piezoelectric polymeric acoustic transducer |
| DE3590430T1 (en) * | 1984-08-28 | 1986-09-18 | Matsushita Electric Industrial Co., Ltd., Kadoma, Osaka | Loudspeaker system with a pronounced directional effect |
| JP2745147B2 (en) * | 1989-03-27 | 1998-04-28 | 三菱マテリアル 株式会社 | Piezoelectric transducer |
| US5357578A (en) * | 1992-11-24 | 1994-10-18 | Canon Kabushiki Kaisha | Acoustic output device, and electronic apparatus using the acoustic output device |
| US6304662B1 (en) * | 1998-01-07 | 2001-10-16 | American Technology Corporation | Sonic emitter with foam stator |
| US5859915A (en) * | 1997-04-30 | 1999-01-12 | American Technology Corporation | Lighted enhanced bullhorn |
-
1999
- 1999-08-26 CN CNB998126802A patent/CN1181704C/en not_active Expired - Fee Related
- 1999-08-26 EP EP99946657A patent/EP1123634A4/en not_active Withdrawn
- 1999-08-26 CN CN 200410087797 patent/CN1620195A/en active Pending
- 1999-08-26 BR BR9913954-5A patent/BR9913954A/en not_active Application Discontinuation
- 1999-08-26 JP JP2000571709A patent/JP2002526004A/en active Pending
- 1999-08-26 CA CA002345339A patent/CA2345339A1/en not_active Abandoned
- 1999-08-26 WO PCT/US1999/019580 patent/WO2000018182A1/en not_active Application Discontinuation
- 1999-08-26 AU AU59020/99A patent/AU5902099A/en not_active Abandoned
-
2002
- 2002-05-04 HK HK02103388A patent/HK1041763A1/en not_active IP Right Cessation
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102082551A (en) * | 2010-12-16 | 2011-06-01 | 瑞声声学科技(深圳)有限公司 | Audio-frequency playback system of parametric acoustic array and modulating method thereof |
| CN105378957A (en) * | 2013-05-08 | 2016-03-02 | 达尔豪西大学 | Acoustic transmitter and implantable receiver |
| US11256338B2 (en) | 2014-09-30 | 2022-02-22 | Apple Inc. | Voice-controlled electronic device |
| US11818535B2 (en) | 2014-09-30 | 2023-11-14 | Apple, Inc. | Loudspeaker with reduced audio coloration caused by reflections from a surface |
| US10609473B2 (en) | 2014-09-30 | 2020-03-31 | Apple Inc. | Audio driver and power supply unit architecture |
| US11290805B2 (en) | 2014-09-30 | 2022-03-29 | Apple Inc. | Loudspeaker with reduced audio coloration caused by reflections from a surface |
| US10587950B2 (en) | 2016-09-23 | 2020-03-10 | Apple Inc. | Speaker back volume extending past a speaker diaphragm |
| US10834497B2 (en) | 2016-09-23 | 2020-11-10 | Apple Inc. | User interface cooling using audio component |
| US10911863B2 (en) | 2016-09-23 | 2021-02-02 | Apple Inc. | Illuminated user interface architecture |
| US10771890B2 (en) | 2016-09-23 | 2020-09-08 | Apple Inc. | Annular support structure |
| CN107872757B (en) * | 2016-09-23 | 2020-06-05 | 苹果公司 | Audio driver assembly and array speaker |
| US11693488B2 (en) | 2016-09-23 | 2023-07-04 | Apple Inc. | Voice-controlled electronic device |
| US11693487B2 (en) | 2016-09-23 | 2023-07-04 | Apple Inc. | Voice-controlled electronic device |
| CN107872757A (en) * | 2016-09-23 | 2018-04-03 | 苹果公司 | Extend through the loudspeaker back cavity of loudspeaker diaphragms |
Also Published As
| Publication number | Publication date |
|---|---|
| EP1123634A4 (en) | 2006-04-19 |
| HK1041763A1 (en) | 2002-07-19 |
| JP2002526004A (en) | 2002-08-13 |
| BR9913954A (en) | 2002-02-13 |
| EP1123634A1 (en) | 2001-08-16 |
| CN1181704C (en) | 2004-12-22 |
| CA2345339A1 (en) | 2000-03-30 |
| WO2000018182A1 (en) | 2000-03-30 |
| CN1331901A (en) | 2002-01-16 |
| AU5902099A (en) | 2000-04-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1181704C (en) | Parametric loudspeaker with electro-acoustical disphragm transducer | |
| US20050244016A1 (en) | Parametric loudspeaker with electro-acoustical diaphragm transducer | |
| CN1198480C (en) | Acoustic device | |
| US10117018B2 (en) | Speaker module | |
| US6535612B1 (en) | Electroacoustic transducer with diaphragm securing structure and method | |
| CN1581891A (en) | Sound reproduction device and portable terminal apparatus | |
| CN1655645A (en) | Loudspeaker and apparatus using loudspeaker | |
| US9998833B2 (en) | Speaker | |
| US6278787B1 (en) | Loudspeakers | |
| CN1190107C (en) | Piezoelectric film sonic emitter | |
| JPWO2009063905A1 (en) | Piezoelectric acoustic element and electronic device | |
| JP2007503742A (en) | Parametric transducer with emitter film | |
| US6606390B2 (en) | Loudspeakers | |
| CN1946248A (en) | Electrostatic ultrasonic energy exchanger and ultrasonic loudhailer | |
| CN101959105B (en) | Electrostatic loudspeaker | |
| US20180367889A1 (en) | Sound Generator | |
| CN212850997U (en) | Sound production unit and electronic equipment | |
| CN1135903C (en) | Piezoelectric loudspeaker | |
| CN1135058C (en) | Acoustic device according to bending wave principle | |
| US20020076069A1 (en) | Sonic emitter with foam stator | |
| CN207652682U (en) | A kind of sound-producing device | |
| US11509996B2 (en) | Devices for playing acoustic sound and touch sensation | |
| TWI824533B (en) | Thin speaker | |
| JP4016697B2 (en) | Speaker device | |
| CN115708363A (en) | Passive sounding device integrated to flat panel display |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| REG | Reference to a national code |
Ref country code: HK Ref legal event code: DE Ref document number: 1078729 Country of ref document: HK |
|
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Open date: 20050525 |
|
| REG | Reference to a national code |
Ref country code: HK Ref legal event code: WD Ref document number: 1078729 Country of ref document: HK |