WO2005094701A1 - Ultrasonic wave irradiating method and ultrasonic wave irradiating device - Google Patents

Abstract

Using information collected from the behavior of produced cavitation air bubbles, ultrasonic irradiation is optimized. An ultrasonic wave irradiating method comprises a first step including a first sub-step of irradiating with a high-frequency ultrasonic wave an object around which liquid is partly present at least in a region and producing cavitation air bubbles in a region containing the object, a second sub-step of irradiating the object with a low-frequency ultrasonic wave, breaking the cavitation air bubbles, and imparting high energy to the object, and a third sub-step of taking an interval time after the second sub-step and a second step of collecting sound waves emitted from cavitation air bubbles, signal-processing the sound waves, and controlling the ultrasonic wave irradiation condition. The second step includes judging whether or not stable cloud cavitation is produced, whether or not the crush position is adequate, whether or not the crush pressure is adequate, and whether or not the number of residual air bubbles is small enough.

Description

 Specification

 Ultrasonic irradiation method and ultrasonic irradiation device

 Technical field

 The present invention relates to an ultrasonic irradiation method and an ultrasonic irradiation device, and more particularly to crushing, cleaning, surface modification, and the like of an object using the collapse pressure of cavitation bubbles. In the present specification, the present invention will be described based on one preferred embodiment, calculus crushing, but the present invention is not limited to medical applications such as calculus crushing, but is also applied to ultrasonic cleaning. It is also useful in industrial applications such as cavitation 'peening.

 Background art

 [0002] Shock wave lithotripsy (SWL) is often regarded as an almost established treatment technique at present. However, it is true that calculus fragments are relatively large, and that normal tissue can be damaged by cavitation, leaving unsolved problems. Damage to body tissue is caused by the high impact pressure that occurs when the cavitation bubbles collapse rapidly (collapse). On the other hand, it is clear that the collapse pressure of the cavitation bubbles is strong enough to scrape stones. If it can be localized only on the stone surface and generate cavitation bubbles, and even more effectively cause its collapse, it will minimize damage to normal tissue. It is thought that it is possible to crush only calculi.

[0003] The inventors of the present application have developed a method of controlling ultrasonic cavitation using two types of focused ultrasonic waves and crushing so that only calculi are scraped off from the surface. In this method, only the calculus is crushed by erosion due to the collapse phenomenon of ultrasonic cavitation without using high pressure due to shock waves. As a pressure wave for generating cavitation, focused ultrasonic waves having a wavelength that is about one order of magnitude shorter than a shock wave generated by SWL are used, and cavitation is generated by generating cavitation in a localized region and causing collapse. High pressure only at the surface. This leads to high energy concentration. In this way, we have developed a calculus crushing method that can solve both the problems of existing SWLs: the relatively large size, crushed fragments, and damage to body tissues due to damage to the cavitation. [0004] Until now, in the method using two types of ultrasonic waves, sequential control has been performed by giving an ultrasonic output and an ultrasonic irradiation time that are considered to be empirically appropriate. For example, the time required for cavitation generation was 50 s, and the time required for disappearance was 50 ms. However, in this method of generating a stable cavitation by high-frequency ultrasound and then disrupting it by subsequent low-frequency ultrasound, obtaining a very high pressure in a very limited spatiotemporal domain. It is important to keep track of the condition of the cavitation and to always maintain the optimum condition. In particular, when considering medical applications, it is important to 1) apply the collapse pressure of the cavitation to other than the affected area, and 2) maximize (optimally) induce the collapse of the cavitation in the affected area.

 [0005] Here, according to the studies of the inventors, the crushing force largely depends on the accuracy of generating a stable cloud cavitation, and the generation of a stable cloud cavitation depends on the pressure amplitude at the focal point, It has been found that the optimum ultrasonic irradiation conditions in the system greatly vary depending on the dissolved gas concentration, bubble nucleus concentration, saturated vapor pressure, etc. Here, stable cloud cavitation means that the rate of change in the size and shape of the cloud cavitation is significantly reduced when a certain ultrasonic irradiation time is exceeded, as shown in FIG. Refers to the state in which In addition, the amount of crushing per unit time greatly depends on the number of collapses of the stable cloud cavitation per unit time, that is, the repetition frequency of high-frequency ultrasonic waves and low-frequency ultrasonic waves. It largely depends on the extinction time of residual bubbles after cloud cavitation collapse. In order to apply the technique using two types of ultrasonic waves to more advanced ultrasonic therapy equipment, a series of behaviors from generation, collapse, and disappearance of acoustic cavitation in a focused ultrasonic sound field are physically grasped. It is necessary to control the concentration of high pressure and high energy.

 Patent Document 1: JP 2004-33476

 Disclosure of the invention

 Problems to be solved by the invention

[0006] The present invention provides a means for generating cavitation by high-frequency ultrasonic waves, disintegrating the cavitation with subsequent low-frequency ultrasonic waves, and generating very high energy in a limited spatiotemporal region.情報 In addition, information that can be used to obtain the behavioral force of the generated cavitation bubbles is used. Therefore, it is an object to optimize the ultrasonic irradiation. The energy concentration efficiency greatly depends on the accuracy of stable cloud cavitation generation.Stable cloud cavitation generation depends on the pressure amplitude at the focal point, dissolved gas concentration, bubble nucleus concentration, saturated vapor pressure, etc. Because of the large dependence, the optimal ultrasonic irradiation method in the system greatly changes depending on these. In addition, the total amount of energy concentrated per unit time greatly depends on the number of times a stable cloud cavity collapses per unit time, that is, the repetition frequency of high-frequency ultrasonic waves and low-frequency ultrasonic waves. Depends greatly on the disappearance time of the residual bubbles after the collapse of the cloud cavitation. For this reason, it is necessary to control the concentration of the energy while constantly grasping the series of behaviors from the generation of ultrasonic power to the collapse and disappearance of the cavitation.

 Means for solving the problem

 [0007] In order to achieve a powerful task, a technical means adopted by the present invention is to irradiate high frequency ultrasonic waves toward an object in which liquid is present in at least a part of its surroundings, and to irradiate a region including the object. A first step of generating cavitation bubbles in the region, a second step of irradiating the object with low-frequency ultrasonic waves to break the cavitation bubbles and apply high energy to the object, and A first step having an interval time (interval step) after the two steps, a first step, and a sound wave emitted from the cavitation bubble are acquired, and the sound wave is subjected to signal processing to obtain ultrasonic irradiation conditions. And a second step of controlling Preferably, the cavitation bubbles are generated in a local region near the object, and the cavitation bubbles are collapsed to locally apply high energy to the object. In a preferred embodiment, the third step of the first step comprises, after the second step, ultrasonic waves of a moderate intensity without irradiating the object with ultrasonic waves or inducing the generation and growth of bubbles. This is the interval time during which only irradiation is performed.

[0008] In one preferred embodiment, the signal processing in the second step includes determining whether or not a force has been generated by the first step in the first step to generate stable cavitation bubbles, and the controlled ultrasonic irradiation condition is high. The output of the ultrasonic wave at the frequency and the Z or irradiation time. Judgment result If the force s is “No”, reset the output of high frequency ultrasonic wave and Z or irradiation time. The controlled ultrasonic irradiation condition may include a frequency of a high frequency ultrasonic wave. The controlled ultrasonic irradiation conditions may further include position adjustment (including phase) of the ultrasonic irradiation device.

 [0009] In one preferred embodiment, the determination as to whether or not a force has generated a stable cavitation bubble is performed by using the pressure amplitude and Z or the magnitude of the pressure of the received signal. In another preferred embodiment, the determination as to whether or not the force has generated stable cavitation bubbles is made by using the frequency component of the received signal.

[0010] In one preferred embodiment of the present invention, the signal processing in the second step includes a determination as to whether the collapse position of the cavitation bubble in the second step in the first step is appropriate, and the ultrasonic irradiation conditions to be controlled are controlled. Is positioning (including phase). If the judgment result is “No”, the position of the device is adjusted. The determination of whether the collapse position of the cavitation bubble is appropriate is made by measuring the time from the transmission of the low-frequency ultrasonic wave to the reception of the sound wave due to the collapse pressure.

[0011] In one preferred embodiment of the present invention, the signal processing in the second step includes determining whether the collapse pressure of the cavitation bubbles in the second step in the first step is appropriate (determining whether the crushing efficiency is appropriate). ), And the controlled ultrasonic irradiation conditions include at least one of the output, wave number, rising time constant, rising phase, and frequency of the low frequency ultrasound. Further, the controlled ultrasonic irradiation conditions may include at least one of parameters (output, irradiation time, frequency) of high-frequency ultrasonic waves, positioning, and phase correction. In one preferred embodiment, the determination as to whether the collapse pressure of the cavitation bubble is appropriate is made by measuring the pressure amplitude and Z or the magnitude of the pressure of the sound wave reception signal based on the collapse pressure.

 [0012] In one preferred embodiment of the present invention, the signal processing in the second step includes a determination as to whether or not residual bubbles in the first step and the third step are sufficiently small. The repetition frequency. In a preferred embodiment, the determination is made based on the collapse pressure of residual bubbles and Z or collapse time.

In the present invention, the processing of the generated acoustic wave force generated sound wave may include obtaining an image of the cavity sound bubble based on the sound wave. Further, the method may include the step of acquiring and signal processing the object and Z or sound waves of the environmental forces around the object. Then, the signal processing is performed on the object and Z or the object. Surrounding environmental forces may also include acquiring an image of the object and the z using the sound wave signal, or an image of the surrounding of the object.

 [0014] In the present invention, the first step and the second step may include, in some preferred embodiments, crushing of an object, separation of foreign matter from the object, surface modification of the object, and thermal denaturation of the object. Including.

 [0015] The present invention is also provided as an ultrasonic irradiation device. An ultrasonic irradiation device according to the present invention includes an ultrasonic irradiation unit that irradiates an ultrasonic wave to an object based on set ultrasonic irradiation conditions, a sound wave reception unit, and a signal that processes a signal received by the sound wave reception unit. A processing unit, and a control unit that controls the ultrasonic irradiation conditions of the ultrasonic irradiation unit. The ultrasonic irradiation unit sends the high-frequency ultrasonic wave to at least a part of the surroundings by the control unit. Irradiate toward an existing object to generate cavitation bubbles in a region including the object, and then irradiate low-frequency ultrasonic waves toward the object to disintegrate the cavitation bubbles. The sound wave receiving unit is controlled so as to impart high energy to the object, receives the sound wave emitted from the cavitation bubble force, and processes the received sound wave by the signal processing unit to generate a signal. The control based on the processing result The unit is configured to control the ultrasonic irradiation conditions.

 [0016] In a preferred embodiment, the sound wave receiving section is an ultrasonic probe and a Z or hide mouth phone.

 [0017] In one preferred embodiment, the signal processing unit includes a sound pressure analyzing unit for the received sound wave. The sound pressure analyzer can analyze pressure amplitude, pressure magnitude, collapse position, collapse time, collapse pressure, and the like.

 [0018] In another preferred aspect, the signal processing unit includes a frequency analysis unit for the received sound wave. The frequency analyzer can analyze pressure amplitude, pressure magnitude, collapse pressure, and the like.

 [0019] In one preferred embodiment, the apparatus further includes a means for irradiating an ultrasonic wave having such an intensity that does not induce the generation and growth of bubbles, so that the object and Z or the environment and Z around the object are irradiated. Alternatively, it is configured such that the reflected sound wave of the ultrasonic wave having the cavitation force is processed by the sound wave receiving unit.

[0020] In one preferred embodiment, the signal processing unit converts image information based on a received sound wave. It includes an image processing unit to be obtained.

 [0021] The ultrasonic irradiation conditions are preferably, but not limited to, the output of high-frequency ultrasonic waves, the irradiation time of high-frequency ultrasonic waves, the frequency of high-frequency ultrasonic waves, the positioning of the ultrasonic irradiation unit with respect to the object, and the repetition frequency. It includes one or more selected low-frequency ultrasonic power, wave number, rising time constant, rising phase, and group force including frequency force.

 [0022] In another preferred aspect, the device has a storage unit, and the storage unit stores information indicating a relationship between the ultrasonic irradiation condition and the physical condition.

 The invention's effect

 According to the present invention, by using the information obtained from the behavior of the generated cavitation bubbles, the force or force at which the stable cloud cavitation is generated is determined whether the collapse position is appropriate or not. It is possible to determine whether the pressure is appropriate, whether the residual air bubbles are sufficiently small, etc., based on the result of the determination, reliably generate a stable cloud cavitation, and reliably and accurately obtain a stable cloud cavitation. It can lead to disintegration at an appropriate time and position, and reset the ultrasonic irradiation conditions to the optimal repetition frequency.

 BEST MODE FOR CARRYING OUT THE INVENTION

[A] Ultrasonic irradiation method using two kinds of frequencies

 First, ultrasonic irradiation using two types of frequencies according to the present invention will be described. First, the basic configuration of the calculus breaking device will be described. FIG. 1 shows a schematic diagram of an ultrasonic cavitation experimental apparatus according to the present invention. As a source of focused ultrasound, a concave PZT (lead zirconate titanate) transducer with an aperture of 80 mm and a focal length of 80 mm fixed to an acrylic water tank was used. Two types of PZT devices, one with a resonance frequency of 1.08 MHz and one with 545 kHz, were used. As a characteristic of the PZT element, in addition to the fundamental mode resonance frequency, there are (2n + l) times higher-order mode resonance points, and higher output is possible compared to other frequencies.

[table 1] Table 1 Resonant frequency of PZT elements that are used in the experiment

1 ^st mode 2 ^nd mode 3 ^rd mode 4 ^th mode

545 kHz 1.64 MHz 2.75 MHz 3.82 MHz

1.08 MHz 3.27 MHz Not use Not use

[0025] In the PZT transducer, the waveform of the ultrasonic wave transmitted into the acrylic water tank is created on a PC, then generated by an arbitrary waveform generator (Agilent, 33120A), and an ultrasonic band amplifier (T & C Power Conversion) is used. , AG 1024) and sent to the PZT element. The transmitted ultrasonic wave is focused at the position of 80 mm, which is the geometric focal point of the concave PZT element. The maximum output of AG1024 is 2 kW for continuous sine wave transmission and 800 V for voltage amplitude during pulse transmission.

 [0026] The IMACON 200, a frame mode super high-speed camera manufactured by DRS Hadland, was used for observation of the phenomenon of cavitation. The IMACON 200 has a minimum exposure time of 5 ns and an interframe of 5 ns, and has sufficient performance to capture the cavitation phenomenon generated by ultrasonic waves on the order of MHz. In addition, a high-speed camera is equipped with a long-distance microscope (Quester, QM100, focal length 150-350).

By attaching a mm), were taken region of 0.33mm X 0.40mm~2.50mm X 3.06m to CCD image 1200pix X 980 _P ix. Light was collected in the cavitation generation range using a high-intensity strobe point light source (Nisshin Electronics, SA200F) having a maximum light intensity of 200 J / flash. The light from the point light source was converted to parallel light by the lens system, and then led to the test section, where observation of the phenomenon of ultrasonic cavitation and shadowgraph photography of the shock wave due to collapse were performed. The sound pressure due to the cavitation collapse was measured with a shock wave measuring hood (IMOTEC, Type 80-0.5-4.0, rise time 50ns). In addition, data synchronized with sound pressure measurement and phenomena shooting with a high-speed camera were performed based on the trigger signal of the power of the arbitrary waveform generator. Aluminum spheres were used as solid walls for growing cavitation. The experiment was performed with the water in the water tank being continuously degassed to a dissolved oxygen concentration of 1.0 to 2.0 ppm.

[0027] Fig. 2 is a schematic diagram of the cavitation control method and a diagram of the acoustic cavitation control. The outline of the ultrasonic pulse waveform used is shown. The control of the acoustic cavitation is done by focused ultrasound with two different frequencies. One is high-frequency (about 1 to 4 mm) ultrasonic waves that generate cavitation in a narrow area (Figs. 2-1 and 2). High-frequency ultrasonic waves generate cloud cavitation in the focal region, which is composed of many microbubbles. The other ultrasonic wave is a low-frequency ultrasonic wave (approximately 100 kHz to 1 MHz) having a frequency near the resonance frequency as a group of cloud bubbles, which is lower by about one order than the high-frequency ultrasonic frequency. 2 As shown below, high-frequency ultrasonic waves are applied immediately after stopping. This low-frequency ultrasonic wave forcibly vibrates the cloud generated at high frequency, leading to collapse (Figs. 2-3 and 4). The shock wave is focused inside the cloud placed in the oscillating pressure field, and the bubble collapses violently in the center (Fig. 2-5, 6). As a result of this series of schemes, cloud cavitation is generated at spatially controlled locations, and its collapse can be induced to achieve efficient lithotripsy.

Next, the collapse behavior of the cloud cavitation will be described. Figure 3 shows the behavior of the cavitation when the acoustic cavitation is actually generated and collapsed by focused ultrasound using the above method. Figure 3 (a) shows how cloud cavitation created by 2.75MHz high-frequency ultrasound is guided to collapse by 545kHz low-frequency ultrasound.

[0029] A semi-elliptical cloud cavitation as seen in the first frame of Fig. 3 (a) is generated while maintaining a stable size 'shape if the frequency of the high frequency ultrasonic wave is the same. I can do it. In addition, it is known that cloud cavitations generated at different frequencies strongly depend on the wavelength of ultrasonic waves. Cloud cavitation can be generated. Supplement this. After continuous ultrasonic irradiation for 100 to 200 s, the state of cloud cavitation developed on the wall was observed. Figure 26A shows a semi-elliptic spherical cloud cavity of stable size and shape created by focused ultrasound at various frequencies. At all frequencies of 1.67, 2.75, 3.27, and 3.82 MHz, a stable semi-ellipsoidal cloud cavity was formed in the focal region of the ultrasonic wave on the solid wall. In addition, cloud cavities as shown in Figure 26A FIG. 26B shows the representative length of the chillon plotted against the frequency. The maximum length of the cloud in the direction normal to the solid wall was used as the representative length. According to Figure 26B, the length of the cloud cavitation generated on the solid wall surface by the ultrasonic wave has a strong correlation with the wavelength of the ultrasonic wave, and fits very well to the line that is a quarter of the wavelength. are doing. It is considered that the reason that the bubble cloud size is uniquely determined by the wavelength is that the sound field generated by the standing wave near the solid wall greatly affects the cloud generation region. As a result, FIGS. 26A and 26B show that the cloud cavitation developed on the solid wall surface by the focused ultrasonic wave can control the generation region by the wavelength of the ultrasonic wave. In addition, it was found that an ultrasonic wave of 1.0 MHz or more can be guided to a localized area of 1.0 mm or less.

 [0030] In the second and third frames in Fig. 3 (a), the volume of each bubble constituting the cloud is reduced in the positive pressure part of the semi-elliptical cloud cavitation force 545 kHz ultrasonic wave. It can be seen that it has collapsed. At this time, it is considered that many bubbles are violently collapsed in the center of the cloud cavitation, exerting a very high pressure on the solid surface. That is, by breaking down the cloud cavitation, high pressure can be spatially controlled and focused only on the calculus surface.

 FIG. 3 (b) is a shadow graph (shadow picture) image of the state of shock wave propagation due to the collapse of the cloud cavitation that occurs subsequent to FIG. 3 (a). The ultrasonic frequency corresponds to the phenomenon immediately after the collapse of the cloud cavitation in the third frame in Fig. 3 at different forces. The high frequency ultrasonic wave is 3.82 MHz, and the low frequency applied subsequently is 545 kHz. In Fig. 3 (b), it can be seen that the spherical wave centered on the bubble cloud propagates outside. In the shadow graph image, a portion where the gradient of the density change is large appears as a shade of black and white. That is, the shadow of the shock wave shown in Fig. 3 (b) indicates that a very high pressure is generated at that location. Actually, when the impact pressure at this time was measured from a distance, it was observed that the pressure value was at least three times greater than the impact pressure at the time when each single cavitation bubble collapsed.

[0032] Furthermore, the phenomena in Figs. 3 (a) and 3 (b) are observed every time in almost the same frame taken by a high-speed camera, and even in a shock pressure sensor measured at a long distance, the cloud cavitation. Collapse The variability of the breaking signal was ± 100 nsec. From this, it was found that according to this method, it is possible to focus high pressure and high energy in a time-controlled region.

 [0033] A crushing experiment will be described. Here, we describe the results of confirming the applicability of model stones' kidney stone crushing using the above method. Figures 4 (a) and 4 (b) show the results of applying this method to model calculi. Fig. 4 (a) shows the model stones for each ultrasonic irradiation time, and Fig. 4 (b) shows the crushed pieces. The cavitation control waveform was the same as that shown in Fig. 2. A group of high frequency and low frequency was defined as one pulse, and ultrasonic waves were irradiated at a repetition frequency of 25Hz. In other words, cloud cavitation collapses 1500 times per minute on the stone surface.

 [0034] From FIG. 4 (a), it can be seen that the calculus is crushed so as to be scraped off from the surface. Twelve minutes later, the model stone had lost almost one-third of its mass, and in 30-40 minutes the model stone was completely crushed. This is as efficient as the total treatment time with existing SWL devices (60-120 minutes). Also, from FIG. 4 (b), it can be seen that the crushed pieces have been crushed so as to be scraped off by the cavitation erosion. All fragments are less than 1 mm and are considered large enough to pass painlessly through the urethra.

 [0035] Fig. 4 (c) shows the application of this method to cystine stones, which are the hardest kidney stones and are considered difficult to crush with existing SWL equipment. As in the case of the model stone, it can be seen that the stone has been scraped off to the crushed piece, very finely. According to this method, 1) stones are removed by cavitation erosion, and crushed pieces can be very finely focused.2) Ultrasonic cavitation that causes crushing is localized only on the stone surface. Is done. Therefore, it has the potential to solve two problems of existing SWL devices: the relatively large size of calculus fragments and the damage to normal tissue in the body during crushing. For the ultrasonic irradiation method using two kinds of frequencies, the description of JP-A-2004-33476 can be appropriately referred to.

 [B] System Using Feedback Control

 [B-1] Background of feedback control

In the ultrasonic irradiation method using the above two types of frequencies, the collapse of the cavitation In order to derive this, it is necessary that the desired stable cloud cavitation is accurately generated in the cavitation generation process. The inventors have conducted extensive studies and found that the crushing force largely depends on the generation of stable cloud cavitation. In addition, the range in which stable cloud cavitation can be generated is limited.For example, in the experimental system shown in Fig. 1, as shown in Figs. It was also clear that it depends on the ultrasonic irradiation conditions such as the ultrasonic irradiation time or the Z and ultrasonic output. Here, the magnitude of the ultrasonic output has a strong correlation with the magnitude of the pressure amplitude of the ultrasonic wave at the focal point, but in many cases, the effects of reflection, refraction, and scattering in the ultrasonic wave propagation process cannot be ignored. Furthermore, the relationship between the pressure amplitude at the focal point and the formation of a stable cloud cavitation is highly dependent on the dissolved gas concentration at the focal point, the bubble nucleus concentration at the focal point, the saturated vapor pressure at the focal point, and the atmospheric pressure at the focal point. The optimum ultrasonic irradiation conditions in the system vary greatly depending on these. Therefore, it is important to monitor the state of the cavitation and provide feedback, even when it comes to "stable execution of stable cavitation".

 [0037] On the other hand, it was also found that in the process of generating a stable cloud cavitation, the sound wave generated by the cavitation force changes characteristically. Therefore, it is possible to control so as to generate an appropriate cloud cavitation under various conditions by applying feedback using a sound wave that also generates a cavitation force. In addition, the sound waves generated from the cavitation also have information on the collapse phenomenon and residual bubble vibrations after the collapse, and by analyzing this and applying feedback, the appropriate collapse pressure and the appropriate repetition frequency of ultrasonic irradiation are obtained. (This is directly related to the crushing efficiency).

In the present invention, as a specific monitoring method, as one preferable embodiment, a sound wave that also generates a cavitation force can be used. Figure 7 shows the sound generated from the cavitation. By processing this sound, the target at the focal position, whether or not the cavitation is generated, whether or not crushing is sufficiently performed, and optimization of the repetition frequency of the ultrasonic wave can be all performed. As shown in Fig. 7, when the cloud is stabilized, the signal corresponding to the irradiation time of the high-frequency ultrasonic wave changes. Therefore, it is determined whether stable cloud cavitation is generated by monitoring the signal change. It is. When the cloud collapses, an impact pressure corresponding to the strength of the collapse is observed. The collapse pressure is estimated from the pressure amplitude and Z or the magnitude of the pressure of the sound wave reception signal due to the impact pressure, and it can be determined whether the crushing efficiency is appropriate. In this technology, since the object (calculus) is crushed so that it can be scraped off by the erosion, it is important to say at what speed the object (calculus) is scraped off. Therefore, the crushing efficiency is, for example, the amount of weight (mg / min) scraped off per unit time. Also, the residual bubbles collapse after 100-200 s, generating acoustic waves. The optimal repetition frequency is determined from the pressure amplitude and Z or the magnitude of the pressure of the sound wave reception signal, and the collapse time.

 [0039] [B-2] Overall configuration of the system

 The overall configuration of the system will be described. The calculus breaking method (CCL: Cavitation Control Lithotripsy) using the collapse pressure of the cavity is configured as shown in Fig. 5. The system can be broadly divided into stone capture and stone crushing. Calculus capture includes calculus position measurement, coarse / fine movement of the ultrasonic generator, and phase correction of the ultrasonic generator. Fracture of a calculus involves two steps: high-frequency ultrasonic irradiation and low-frequency ultrasonic irradiation. The calculus crushing process is related to the process until the generation of cavitation bubbles also disappears. Disappearance is important.

 [0040] Irradiation of high-frequency ultrasonic waves is related to generation of stable cloud cavitation, and is performed during or after irradiation of high-frequency ultrasonic waves (including after irradiation of low-frequency ultrasonic waves). By monitoring the generation state of the cloud, it is determined whether or not the force is generating stable cloud cavitation. The irradiation of low-frequency ultrasonic waves is related to the collapse of cloud cavitation, and by monitoring the collapse phenomenon during or after the irradiation of low-frequency ultrasonic waves, it is possible to determine the force at which appropriate collapse is performed. I do. In addition, the residual bubbles are monitored after irradiation with the low-frequency ultrasonic wave to determine whether or not the cavitation bubbles have disappeared (or are sufficiently small). Steps (1) and (2) in the flowchart shown in FIG. 6 correspond to a calculus capturing block, and steps (3) to (8) correspond to a calculus crushing block.

[0041] The ultrasonic irradiation apparatus according to the present invention receives the emitted sound waves. Have means to do so. In the experimental apparatus of FIG. 1, a hide-and-mouth phone is used as a sound wave receiving means. One preferred form of the receiving means is an ultrasonic probe. FIG. 12 illustrates three types of receiving means. The left figure in Fig. 12 shows an ultrasonic probe installed inside a piezoelectric element that irradiates high frequency and Z or low frequency ultrasonic waves.The center figure irradiates high frequency and Z or low frequency ultrasonic waves. An ultrasonic probe is installed outside the piezoelectric element.For a piezoelectric element that emits high-frequency and Z- or low-frequency ultrasonic waves or a type in which the piezoelectric element is divided into multiple segments as shown in the right figure, The power of these segments is responsible for the receiving function. These forms receive sound waves alone or in combination. Reception can have both the function of monitoring the cavitation bubbles and the function of normal ultrasound diagnosis for imaging of calculus' tissue. In addition, the combination of these receiving means changes the form of the treatment device, whether it is the S phased array system (the focal position can be changed by phase correction) or the single focus system. The sound pressure signal receiving probe may passively receive the sound wave emitted by the cavitation bubble force, or the probe itself may transmit the ultrasonic wave (the waveform generating device is connected to the probe), A reflected wave of the cavitation bubble force with respect to the ultrasonic wave may be received.

[0042] The sound pressure signal received by the ultrasonic probe is subjected to signal processing in a signal processing unit. The signal processing unit has means for obtaining the pressure amplitude and Z or the magnitude of the pressure of the received sound pressure signal, and analyzes the sound pressure signal (frequency component extraction by frequency filter, Fourier transform such as FFT) Frequency analysis), and a means for obtaining image information from a sound pressure signal. The pressure amplitude of the sound pressure signal, the magnitude of Z or pressure, and the frequency component of the sound pressure signal can be used as parameters in the feedback loop. In addition, the acquired image information is displayed on the display unit, and the image information can be used for feedback control.

[0043] [B-3] Crushing procedure using feedback system

A series of flow of the crushing method using the feedback system will be described based on a flowchart. The dependence of the physical parameters on the ultrasonic parameters is stored as a database in the storage unit of the device. Where the ultrasonic parameters are Means parameters including the focal position of the device, specifically the position of the ultrasonic generator and receiver (including those due to phase correction), the output of high-frequency ultrasonic waves, irradiation time, frequency, low frequency The ultrasonic wave output 'wave number' rise time constant 'rise phase' frequency and repetition frequency of the first step. Physical parameters include dissolved gas concentration, liquid type, liquid temperature, bubble nucleus concentration, saturated vapor pressure, atmospheric pressure, etc.S, and other factors such as the acoustic impedance and surface impedance of the object. Includes roughness and the like.

 [0044] The ultrasonic parameters are set based on the database and the information on the calculus position (Step 1). Information on the calculus position is obtained, for example, by ultrasonic diagnosis. In this step, for example, positioning is first performed, then the parameters of the high-frequency and low-frequency ultrasonic waves and the repetition frequency are provisionally set, and then only the high-frequency ultrasonic waves are actually continuously irradiated. Receiving the sound waves from the cavitation, and resetting the parameters of the high-frequency ultrasonic waves using the feedback method of step 5 described later, and optimizing the low-frequency ultrasonic waves and the repetition frequency are performed in steps 2 to 8. This is performed in a loop.

 [0045] In order to follow the movement of the calculus, the position of the calculus is measured again, and the apparatus is positioned (including that obtained by phase correction) (step 2). At this time, if it is impossible to follow the movement of the calculus in real time, it is possible to return to step 1 again and set the initial force and the ultrasonic parameters again.

 Irradiate high frequency ultrasonic waves to generate stable cloud cavitation (step 3). Irradiation of high frequency ultrasound is performed based on the parameters set in step 1. The range of the high frequency is 100 kHz or more, preferably 500 kHz to 10 MHz.

 [0047] Subsequently, low-frequency ultrasonic waves are applied to induce cloud cavitation to collapse and crush stones (Step 4). The low frequency range is less than half the frequency of the ultrasonic wave applied in step 3.

[0048] It is determined whether a stable cloud cavitation has been generated (step 5). Since the process of step 3 is completed in a very short time, for example 50 s, the monitoring of the cavitation generation is after step 4. This is because it takes about 50 seconds to receive the sound wave generation power from the cavitation. Of course, if this technique is used for different systems, this is not the case. It is desirable to do. Here, for example, the monitoring of the cavitation is performed using the characteristic sound wave at the time of the generation of the cavitation or the characteristic sound wave from the stable cavitation. If it is determined that stable cavitation has been generated, step

Proceed to 6. If it is determined that stable cavitation has not been generated, the process returns to step 2.

 It is determined whether or not the collapse position and Z of the cavitation bubble have the correct collapse time (step 6). From the sound wave reception timing by the collapsing pressure, it can be confirmed whether or not the collapsing occurs at a position apart by the focal length! /. For example, it is possible to perceive that a collapse has occurred in the side lobe just before the focal point. Furthermore, if it is determined that the collapse position of the cavitation bubble is correct, the process proceeds to step 7. If it is determined that the collapse position of the cavitation bubble is not correct, return to step 2.

 [0050] It is determined whether the collapse pressure of the cavitation bubble is appropriate (step 7). From the pressure amplitude of the sound wave due to the collapse pressure and the Z or pressure magnitude value, the collapse pressure at the focal point can be estimated. This makes it possible to check whether the pressure (or pressure amplitude) required for crushing has been obtained. If the collapse pressure is determined to be appropriate, proceed to step 8. If it is determined that the collapse pressure is not appropriate, return to step 2.

 [0051] It is determined whether the residual air bubbles are sufficiently small (Step 8). By receiving the sound waves from the residual bubbles after collapse, the state of the residual bubbles can be monitored. The reception of the sound wave from the bubble may be reception only, transmission / reception, or a combination thereof.

 [0052] [B-4] Monitoring of cavitation bubble formation

 The power of stable cloud cavitation is determined by the change in sound pressure amplitude 'stabilization of sound pressure amplitude' detection of harmonic signals generated from bubbles' and the actual collapse of the cloud at low frequencies A plurality of methods such as whether or not a signal can be obtained are conceivable. This information can be obtained by processing the signal of the received sound pressure of the cavitation bubble force.

[0053] One preferable example of a normal cavitation control cycle is (1) generation of cavitation, (2) generation of stable cloud cavitation, (3) collapse of stable cloud cavitation, ( 4) The cavitation disappears and the power becomes stronger. Of these, processes (1), (2) and (3) are cheaper. It is a part that interacts with the generation of a stable cloud cavitation, and it is possible to check the generation of a stable cloud cavitation in this process.

 [0054] In (1), the occurrence of cavitation is detected, and if it has occurred, it is possible to predict how long the irradiation time will lead to the generation of a stable cloud cavitation. In (2), confirm whether the cloud cab is stable. However, if it is difficult to detect the sound wave of a stable cloud cavitation, it is possible to use a feature that makes it difficult to detect it. In order to increase the accuracy, it is possible to use (1), (3) It is thought that confirmation in the process of) will also be important. In (3), it can be confirmed that if the collapse according to the database (or sufficiently large) has occurred, a stable cloud cavitation can be generated as a result.

 As a specific determination method, the determination is performed based on the pressure and frequency components of the sound wave. The use of the pressure value will be described with reference to FIG. FIG. 7 shows the relationship between the sound pressure of the received signal of the sound emitted from the cavitation cloud and time. As shown in Fig. 7, when the cloud is stabilized, there is a change in the signal during irradiation of high-frequency ultrasonic waves. For example, in FIG. 7, after the pressure amplitude once increases with a change, the value is reduced with time, and the pressure amplitude is stabilized at a substantially constant pressure amplitude. By monitoring such a signal change, it is determined whether a stable cloud cavitation is generated. When the cloud collapses, an impact pressure corresponding to the strength of the collapse is observed. If the collapse according to the database has occurred, it can be determined that a stable cloud cavitation can be generated as a result.

 As for the frequency component, for example, since the sound pressure signal emitted in the process of generating the cavitation has a wide frequency band, it can be detected at a frequency lower or higher than the frequency of the irradiation ultrasonic wave. If this becomes a stable cavitation, the frequency component is almost limited to a harmonic component that is an integral multiple of the irradiated ultrasonic wave. Therefore, by examining (1) the distribution (spread and variation) of frequency components, and (2) specific frequency components (such as 1/2 times subharmonic components and 2 times higher harmonic components) It can be determined.

[0057] A feed when stable cloud cavitation is generated and the determination as to whether it is "no" The parameters to be back-controlled are high-frequency ultrasonic parameters (high-frequency irradiation time

, High frequency output). Figure 8 shows the relationship between the minimum output required for stable cloud cavitation and the minimum irradiation time. The generation of a stable cloud cavitation depends on the output of high-frequency ultrasonic waves and the irradiation time of ultrasonic waves. Furthermore, high-frequency frequencies are also controlled. As a result, the size of the cloud cavitation to be generated can be changed, and the crushing force (power, range, etc.) can be changed.

 [0058] In the case of "judgment of whether or not stable cloud cavitation is generated", for example, the irradiation time of high frequency and the output of Z or high frequency are made longer and larger. However, in the case of “judgment power”, it is not always the case that the irradiation time of the high frequency and the Z or the output of the high frequency are merely increased for a long time. For example, if the bubble is not the target after passing a stable situation! / If it is also generated in a place, the high-frequency irradiation time and Z Become.

 [0059] Similarly, when the frequency is changed, a stable cloud cavitation is generated. In the case of the force judgment power "No", the frequency is basically lowered, but the bubble is not the target. If it occurs in some places, it is necessary to increase the frequency in order to reduce damage to body tissues and increase efficiency. Regarding the fact that "bubbles are generated at the place where they are not intended", if the imaging is performed in the manner of ultrasonic diagnosis, it is possible to determine the accuracy and the force up to that position. However, since this is not always possible, (1) stable cloud cavitation force, whether the sound waves are kept in a stable state, and (2) multiple positional forces with collapse pressure can be obtained. Therefore, it is necessary to first determine whether the error has occurred because it is not checked (checked at the reception timing). Ultimately, there may be an embodiment in which the doctor makes a decision on the (3) ultrasonic imaging image.

 In the flowchart shown in FIG. 6, strictly speaking, the high-frequency output ′ irradiation time is changed.

Loop exists. For simplicity of the figure, the process returns from step 8 to step 2.However, first, the output of the ultrasonic parameter high-frequency irradiation time is changed, and the high-frequency output For example, re-positioning will also redo the force. Other parameters include phased array For example, a change in phase between individual elements is a parameter.

 [0061] [B-5] Monitoring of bubble collapse phenomenon of cavitation

 By monitoring the cavitation bubble collapse phenomenon, it is determined whether the collapse position is appropriate and the force collapse pressure is appropriate. In the determination of the collapse position, `` confirmation of whether or not collapse has occurred at a position separated by the focal length from the sound wave reception time by the collapse pressure '' means measuring the time from low-frequency transmission to reception of the collapse pressure. Done by The time may be measured directly, for example, since the irradiation time of a high frequency is known, it may be measured indirectly by measuring the time of the transmitting power of a high frequency.

 [0062] When the collapse position of the cavitation bubble is incorrect, in the case of manual positioning, the position of the device is adjusted by feedback control. In the case of the phased array system, the phase of each element is also a parameter as a positioning parameter.

 [0063] The collapse pressure at the focal point is estimated from the relationship between the crushing efficiency of the calculus itself and the received sound pressure. (Because the collapse pressure itself cannot be measured, the received sound pressure is considered to be a parameter that depends on the collapse pressure.) The information we finally obtained is the calculus breaking efficiency and the amount of damage to body tissue. Since both of these have a strong correlation with the collapse pressure, it is also possible to create a database of each relationship through the collapse pressure predicted from the received sound pressure, and directly receive the sound pressure and the crushing efficiency and the magnitude of damage. It is also possible to make a database of the relationships between the two.

 [0064] When an appropriate collapse pressure is not obtained, the object of feedback control is to change the output and wave number of the low frequency, to change the time constant of the low frequency rise, There are two ways to change the rising phase and the low frequency. In addition to the low-frequency parameters, any one of the high-frequency parameters, the repetition frequency, the positioning, and the phase correction (if the phase correction is possible), or a combination of a plurality of them is also a control target. For example, first adjust the low frequency parameters, and if the appropriate collapse pressure is still not obtained, combine the high frequency parameters, positioning, and phase correction to achieve the target state.

 [B 6] Monitoring of residual bubbles in cavitation

In the present technology, one of the points is to use the cavitation limited to a narrow area. However, the residual bubbles after the collapse of the cavitation are stable cloud cavitation. Is generated or diffused in the region other than the region where the high frequency force is generated, so even if the cycle starting with the high frequency force is repeated as it is, it becomes impossible to control in a local region. Therefore, it is most efficient to start the next cycle when the residual bubbles have become negligibly small. Therefore, monitoring of the residual air bubbles is performed, and the time until the next cycle (that is, the repetition frequency) is determined.

 [0066] The state of the residual bubbles is monitored by receiving a sound wave from the residual bubbles after the collapse. The state of the residual bubbles means the size and the total volume of the residual bubbles. These parameters can be predicted from the magnitude of the collapse pressure (sound wave) from the residual bubbles and the time interval at which the collapse pressure occurs. In addition, there is also a method of irradiating the residual bubbles with ultrasonic waves that do not induce the generation and growth of residual bubbles, and monitoring the state of the residual bubbles by receiving the reflected sound waves. This is an effective method. The magnitude of the collapse pressure from the residual bubbles directly indicates the magnitude of the volume of the residual bubbles. This is because the collapse pressure of a single bubble increases as the bubble radius increases. In addition, the fact that the collapse pressure generation time is slow and the interval between the collapse pressure generation times is long also mean that the volume of the residual bubble is large. If the bubble is large, it is a force that naturally lowers the natural frequency of the bubble vibration.

 [0067] If it is determined by the monitoring of the residual bubbles that the disappearance of the cavitation bubbles is insufficient, the repetition frequency is reset to a low value. If it is determined that the cavitation bubbles disappear quickly enough, the repetition frequency is set to a higher value.

 [0068] The relationship between the monitoring of the residual bubbles and the resetting of the repetition frequency will be described. The more (if larger) the residual air bubbles, the lower the repetition frequency must be. Conversely, if the residual bubbles are small, the repetition frequency can be increased and the crushing efficiency can be increased. If the repetition rate can be doubled, the treatment time will be shortened by half, and this will have a direct effect on the crushing efficiency, so this process is a very important sequence.

FIG. 11 shows a time chart of a protocol of ultrasonic irradiation and ultrasonic reception. The interval between two pulses of the ultrasonic irradiation power according to the present invention, ie, the waiting time of 10,000 to 40,005, excluding the monitoring time of the cavitation bubble, varies. Therefore, using the waiting time, for example, an ultrasonic wave of 5 kHz PRF (pulse repetition frequency) can be used. By irradiating 0-200 rasters, it is possible to monitor the calculus body and surrounding tissue.

 Example

[C] Outline of Example

 A database of cavitation behavior by high-frequency and low-frequency ultrasonic waves (characteristics of cavitation behavior in a series of schemes) was created, and an experiment was performed to confirm the actual collapse behavior corresponding to the database.

 In particular,

 (1) Creation of a behavioral behavior database (high frequency food);

 Three types of cavitation behavior in the high-frequency phase (Fig. 14, Fig. 15, Fig. 16

)

 (2) Acquisition of sound pressure signal according to the cavitation behavior (high-frequency food);

 Sound wave monitoring in high frequency phase and correspondence with three types of cavitation behavior Examples (Fig. 17, Fig. 18, Fig. 19, Fig. 20)

 (3) Creation of collapse pressure database (low frequency phase);

 Correlation between collapse pressure detection in the low frequency phase and three types of cavitation behavior (Figures 21 and 22);

 Monitoring the collapse pressure in the low frequency phase to extract the conditions that lead to the optimal collapse pressure (Figure 23);

 A pressure-sensitive sheet experiment and a calculus crushing experiment (FIGS. 24 and 25) based on (1), (2), and (3) were performed.

 In the high frequency phase, cavities were classified into three patterns of low, medium, and high according to the magnitude of output, and characteristic monitoring sound pressure waveforms corresponding to the classification were measured. In addition, it was clarified that the collapse pressure was generated optimally at the medium output of the three types, and an example of a database for monitoring the collapse pressure in the low frequency phase was created. Based on these results, two types of confirmation tests were performed: a two-dimensional high-pressure generation region using a pressure-sensitive sheet and a calculus crushing experiment.

[C 1] Experimental apparatus FIG. 13 is a schematic diagram of the experimental apparatus used in this example. The experimental apparatus is an experimental system in which an ultrasonic sensor is arranged at a position simulating monitoring from outside the body. FIG. 13 is a schematic diagram of the experimental apparatus used in this example. The ultrasonic source used was a concave PZT transducer with an aperture diameter of 100 [mm] and a focal length of 80 [mm]. The resonance frequency of the transducer is 555 [kHz] and has a fourth harmonic mode at 3.89 [MHz]. The above two frequencies are used as the high frequency and low frequency of the cavitation control, that is, 3.89 [MHz] for the high frequency phase and 555 [kHz] for the low frequency phase. A high-speed camera IMACON2000 (exposure 10 [nsec], inter-frame 10 [ms] in this experiment) was used to photograph the behavior of the cavitation. For monitoring the sound pressure emitted from the cavitation, a concave-type closed-mouth phone with an aperture of 12 [mm] and a focal length of 78.3 [mm] was used. This concave-type microphone has almost the same focal length as the PZT transducer, and can receive the emitted sound pressure due to the cavitation phenomenon occurring at the focal point with high sensitivity. Since it is used as Passive Cavitation Detector, it will be abbreviated as PCD hereafter.) The PCD has a resonance frequency of 20 [MHz], and has a flat response and sufficient sensitivity in the 10 [MHz] band that is the target of this experiment.

[C 2] Classification of cavitation bubbles in the high frequency (3.89 [MHz]) phase (high frequency phase database)

 Figure 14 shows the results of a high-speed camera photographing the state of bubbles that occur and grow in the high frequency phase of 3.89 [MHz] on the wall. The behavior of the cavitation bubbles on the solid wall at the ultrasonic irradiation time of 0-130 [μs] (0-506 [period]) at various ultrasonic outputs. The ultrasonic output (vertical axis) in the graph is the magnitude of the maximum negative pressure at the focal point (| p) = 4.8-11.7 [MPa]. From these results, it is understood that the behavior of the cavitation bubble group can be largely classified into three types.

 That is,

 (A) Low sound pressure range (| p "<6.5 [MPa]): A state in which no cavitation has occurred or a minute cavitation that cannot be confirmed by the camera has occurred;

(B) Medium sound pressure range (7.4 | p "<9.6 [MPa]): Stable shape and size of semi-elliptical sphere A state in which bubbles (cloud cavitation) are generated;

 (C) High sound pressure range (10.5 [MPaK | p]: In the state where the shape and size of the cavity are unstable, especially around the semi-elliptical spherical bubbles that occur in the medium sound pressure range, A state where irregularly generated relatively large bubbles or bubbles are covered;

It is.

 These behaviors are closely related to the sound pressure emitted by the cavitation bubbles and the collapse pressure in the low-frequency phase. Figures 15 and 16 show this classification in detail.

 Note that the sound pressure ranges of (A), (B), and (C) indicate the values as described above in the case of this figure. These thresholds depend on the state of the medium (dissolved gas concentration, liquid type, liquid Temperature, bubble nucleus concentration, saturated vapor pressure, ambient pressure, impurity concentration, etc.), acoustic impedance and roughness of the solid wall. Because the absolute value itself is important, it is important to note that the "characteristic" that the cavitation behavior transitions by increasing the ultrasonic output from (A) to (B) to (C) is important. Keep it. In other words, by monitoring the "characteristic" and its "characteristic response to the characteristic", it is possible to identify the state of the cavitation by monitoring the "characteristic response". FIGS. 19 and 20 show examples of monitoring the "characteristic response" corresponding to the three states (A), (B) and (C) in this high-frequency phase.

[C 3] Typical length of cavitation bubble group against high-frequency ultrasonic irradiation time (time diameter graph)

Fig. 15 shows the result of measuring the representative length in the ultrasonic wave propagation direction (normal direction of the solid wall surface) in a photograph of the cavitation bubble group in the same photographing as in Fig. 14. That is, the length corresponding to the horizontal axis direction in FIG. 14 is measured. The conditions are the same as in Fig. 14. (A) Low sound pressure range: 4.7 [MPa], (B) Medium sound pressure range: 8.7 [MPa], (C) High sound pressure range: 11.7 [MPa]. Has become. The horizontal axis in Fig. 15 is the ultrasonic irradiation time (however, the time when the first ultrasonic wave was transmitted by the transducer force was set to zero, so the time when the ultrasonic wave reached the focal point was about 54 [sec]). This shows that the cavitation bubble group grows at each output. In the figure, the symbol “〇” indicates the length of the semi-elliptical cavitation bubble group where the solid wall force also grows. The representative length of the cavitation, which can be regarded as a bubble group, is measured. Also, the "▲" mark in the figure

It has a length that covers the semi-elliptic bubbles and covers the secondary cavitation.

 (A) In the “low sound pressure range”, no bubbles were confirmed even after 100 [sec] in the graph. After about 110 [sec], cavitation bubbles begin to be seen and grow over time, but the typical cavitation length is short, about 30-40 [m].

 (B) In the "medium sound pressure range", the bubbles form a stable shape and size. At 80 sec], cavitation bubbles began to be confirmed, and at lSO ^ sec], a stable cavitation bubble group of about 50-60 [/ ζπι] was formed. However, from around 150 [sec], secondary cavitation bubbles may be generated to cover the semi-elliptical spheres of stable size.

 (C) In the “high sound pressure range”, immediately after the generation of the cavitation bubbles (85 [sec]), secondary cavitation bubbles are generated so as to cover the periphery of the semi-elliptical sphere bubbles. Since the presence of such irregular cavitation bubbles may hinder the effective concentration of high pressure on the solid wall surface, in the present technology, this sound pressure region is generally unfavorable in terms of control. it is conceivable that. However, a large collapse pressure can be easily achieved by using a low-frequency phase ultrasonic wave having a sufficiently low frequency and a sufficiently large pressure amplitude so that these bubble groups can collapse together. That is, under such parameter conditions, the higher the output of the high-frequency and low-frequency ultrasonic waves, the more the number of control steps can be reduced.

[C 4] Typical length of cavitation bubble group against high frequency ultrasonic irradiation time (output diameter graph)

FIG. 16 is a graph in which the ultrasonic output is arranged on the horizontal axis for the same result as in FIG. The ultrasonic irradiation time was set to 114 [sec], which is the time when 233 [periods] were applied. According to this, the diameter of the bubble group gradually increases up to an output of about 6.5 [MPa], and a stable shape of a semi-elliptic sphere of about 50 to 60 [μm] at about 7 [MPa] · Size cavitation bubbles. On the other hand, around 10 [MPa], secondary cavitation bubbles are generated. start. As described in FIG. 14, the threshold varies depending on various surrounding conditions. Under this condition, the low sound pressure range is 6.5 [MPa] and the medium sound pressure range is 6.5 [MPa] to 10 [MPa]. A high sound pressure range of 10 [MPa] or more and a range of three different states of the cavitation bubble group can be defined.

 [0075] [C5] Detection of sound pressure released when cavitation occurs

 FIGS. 17A, 17B, and 17C show the results of high-speed camera imaging and the detection of emitted sound pressure at the time of occurrence of cavitation at each frequency of 1.7, 2.8, and 3.9 [MHz]. The emitted sound pressure is detected almost at the same time when the cavitation bubbles are confirmed in the photographed image.

 [C 6] Monitoring waveform of emission sound pressure in high frequency phase

 Figure 18 shows the monitoring of the emitted sound pressure throughout the high frequency phase. Figures 18A, 18B, and 18C show the results of monitoring the sound pressure from the cavitation bubbles using a concave transducer (in this case, the output is shown as the peak-to-peak amplitude of the function generator). The experiments were performed in the same conditions as in Fig. 18, Fig. 19, Fig. 20, and Fig. 24). As shown in Fig. 18A, in the low sound pressure range of 100-300 [mV], there is no change in the received signal. From around 350 [mV], the emission sound pressure of the cavitation starts to be detected. As shown in Fig. 18B, in the middle sound pressure range of 400-600 [mV], the emission sound pressure of the cavitation force is always included in the received signal. Is detected. As shown in Fig. 18C, the received signal is detected even in the high sound pressure range of 700-1000 [mV], but its waveform fluctuates greatly, reflecting the generation of bubbles with irregular shapes and sizes. are doing . On the other hand, in the region of 400-600 [mV] in the medium sound pressure range, the waveform of the received signal shows stable amplitude and breakthrough lines, and the generation and response of the stable size and shape of the cavitation bubble group it seems to do. These results include information as "characteristic response" to three types of "characteristic generation modes" due to differences in sound pressure output of the cavitation bubble group. An example of a typical detection will be described.

 [C7] Example of monitoring by amplitude of sound pressure waveform: magnitude of amplitude of time averaged waveform

FIG. 19 shows the absolute value of the amplitude of the time-averaged waveform of the sound pressure emitted from the cavitation bubble group at each output in the same case as in FIG. Time average The waveforms are the sums of 10 different sampled received waveforms of the same case with the same time, and divided by 10 samples. By performing time averaging, the amplitude of random noise can be relatively reduced. In other words, the amplitude of the signal of the cavitation bubble group force in a stable state increases each time, and the amplitude of the signal from the cavitation bubble group, which exhibits irregular behavior and random behavior in time and phase, is relatively small. It is expected to become. In FIG. 19, corresponding to the original waveform shown in FIG. 18, (A) in the low sound pressure range, no reception signal is detected because no cavitation bubbles are generated or only a very small cavitation is generated. (B) In the middle sound pressure range, the semi-elliptical cavitation bubbles are generated while maintaining a stable shape and size, so that even in the received signal, a signal having the same amplitude and phase is detected every time. The amplitude of the time-averaged waveform also stably assumes a large amplitude. (C) In the high sound pressure range, the magnitude of the pressure amplitude is smaller than in the case of (B) by canceling the irregular components. The processing results synchronized with the three types were obtained.

 It can be seen that such reception signal processing makes it possible to monitor the cavitation bubble group in the focal region.

[C 8] Example of monitoring by frequency component of sound pressure waveform: FFT analysis of received sound pressure

FIGS. 20A, 20B, and 20C show the emission sound pressure and the frequency component of the force of the cavitation bubbles at each output in the same case as in FIG. Fig. 20A corresponds to the low sound pressure range where only minute cavitation occurs. At that time, the main frequency component is only 3.9 [MHz], which is the transmission frequency. Figure 20B corresponds to the medium sound pressure range where the semi-elliptical cavitation bubbles maintain a stable shape and size. At this time, the frequency component corresponding to a harmonic component such as 7.8 [MHz] is the transmission frequency. It rises to a value close to the component of 3.9 [MHz]. Figure 20C shows the high sound pressure range where irregular secondary cavitation bubbles are generated to cover the periphery of the semi-elliptical sphere bubbles.This unstable cavitation causes the reception signal to break down. The line is disturbed, and the value of the component of the frequency lower than 3.9 [MHz] which is the transmission frequency increases. As described above, the received signal at the PCD has characteristic frequency components corresponding to each of the three types in FIG. 18, so that the frequency of the received signal is analyzed, or the low-pass filter and the high-pass filter are used. It can be seen that it is possible to monitor the cavitation bubble group in the focal region by applying a filter for frequency components such as a filter and a bandpass filter to the received signal.

 [C 9] Detection of collapse pressure in low frequency phase

 Fig. 21 shows an example of monitoring the collapse pressure in the low-frequency (555 [kHz]) phase after the high-frequency ultrasonic wave is completed. The upper part shows the original waveform of the PCD reception sound pressure in the low frequency phase, and the lower part cuts the reflected wave due to the low frequency component of 555 [kHz] from the reception signal and extracts the collapse pressure itself of the cavitation bubble group. The pressure amplitude of the low frequency applied from left to right increases. In all cases! High-frequency ultrasonic waves have a medium sound pressure range of 9.5 [MPa] (maximum negative pressure), under conditions where a stable shape and size of a semi-elliptical spherical cloud cavity are generated. is there. Looking at the upper row, it can be seen that the collapse pressure of the bubbles was observed during the reception of the low-frequency reflected wave. In addition, it can be seen that the received sound pressure of bubble group collapse has increased with the increase in sound pressure at low frequencies.

[C10] Relationship between cavitation bubble group generated in high-frequency phase and collapse pressure FIG. 22 shows a relationship between cavitation bubble group and collapse pressure. The horizontal axis in FIG. 22 is the "high frequency ultrasound" pressure amplitude. In addition, the same graph shows the magnitude of the collapse pressure in the “low-frequency phase” with respect to the pressure amplitude of the high-frequency ultrasonic waves, and the diameter of the cavitation bubble group generated by the “high-frequency ultrasonic waves” at that time. . In the graph of the collapse pressure, the magnitude of the collapse pressure signal of the bubble group as shown in Fig. 21 was obtained by averaging the absolute values by taking 100 cases each for various high-frequency ultrasonic wave outputs. Is the thing. From FIG. 22, it can be seen that the collapse pressure of the cavitation bubbles is also significantly related to the three types of cavitation in the high frequency phase. In other words, (A) in the low sound pressure range (0-6.5 [MPa]), no cavitation bubbles are generated, or only very small cavitation bubbles are generated. Not observed or very small. (B) In the medium sound pressure range (6.5-10 [MPa]), the cavitation bubble group gradually increases in size, and the magnitude of the collapse pressure increases accordingly, and 9 [MPa]. Take the maximum value in the vicinity. This is consistent with the area where bubbles of a semi-elliptical spherical shape and shape are stable. Over 9 [MPa] Then the magnitude of the collapse pressure starts to fall. (C) In the high sound pressure range (10 [MPa] or higher), the semi-elliptical spherical bubbles are covered with irregular secondary cavitation bubbles, and the bubbles are reduced to a low frequency of 555 [kHz]. The sound waves can no longer cause the collapse effectively, and the collapse pressure gradually decreases. The process of decreasing the collapse pressure beyond 10 [MPa] corresponds exactly to the region where secondary cavitation bubbles are generated. It can be seen that the morphology of the cavitation bubbles generated in the high frequency phase has a significant effect on the "characteristics" of the collapse pressure in the low frequency phase. In addition, from the results in Fig. 21, the results show that the magnitude of the collapse pressure increases as the output of the low-frequency ultrasonic wave increases. Together with the obtained results, it shows the characteristics of the collapse pressure in the low frequency phase. The force that comes back again As a result of this collapse pressure,

 * High frequency ultrasound is in low sound pressure range: no collapse pressure detection;

 * High-frequency ultrasonic waves in the mid-sound pressure range: the collapse pressure gradually increases and then decreases with the generation of secondary bubbles;

 * High-frequency ultrasonic waves at high sound pressure range: Due to the effects of secondary bubbles, effective collapsing cannot be obtained and the collapsing pressure is smaller than that of medium sound pressure region;

 * Increasing the pressure amplitude of low-frequency ultrasonic waves increases the magnitude of the collapse pressure; that is, the "characteristic" itself is important, and the absolute value of the output threshold that separates each region depends on the surrounding conditions. Not important to change. In the control, the output parameters are changed in the direction to obtain the optimum collapse pressure according to this "characteristic". That is, it is only necessary that the outline of the characteristic can refer to the device power. Here, the “characteristic outline” refers to V and the mapping result of how the magnitude of the collapse pressure is distributed over the entire range of the high-frequency and low-frequency ultrasonic output parameters. ! / Figure 23 shows an example of the mapping.

[C 11] Example of database of collapse pressure against pressure amplitude of high frequency and low frequency ultrasonic waves

Different forms of cavitation bubbles in the high frequency phase, Demonstrate the efficiency of the actual technology for various outputs of high frequency ultrasound and various outputs of low frequency ultrasound, taking into account the characteristics of the collapse pressure in the low frequency phase

Figure 23 shows the result of measuring the magnitude of the collapse pressure.

 Regarding the output of high-frequency ultrasonic waves, the collapse pressure increases from the low sound pressure range to the medium sound pressure range, and decreases when the sound pressure reaches the high sound pressure range. In contrast to this, the "characteristics of the present technology" shown in the previous examples, where the collapse pressure increases as the output increases. In this case, the optimum collapse pressure was obtained at a high frequency of 9.5 [MPa] and a low frequency of 30 [MPa]. Optimization can be performed by changing the control target parameter.

[0082] [C12] Pressure-sensitive sheet experiment

 Figure 23 shows the results of mapping the collapse pressure by monitoring the collapse pressure at a distance. A confirmation test was performed to confirm whether this actually corresponds to the generation of high pressure on the solid wall in the focal region. As an object, an experiment was conducted in which a pressure-sensitive sheet that changes color with respect to high pressure was installed in the focal region, and the output of high-frequency and low-frequency ultrasonic waves was changed in the same manner as in Fig. 23. As shown in Fig. 24, for the output of high-frequency ultrasonic waves, the collapse pressure increases from the low sound pressure range to the middle sound pressure range, and a large discoloration is observed at the center in the middle sound pressure range. Can be On the other hand, at the high sound pressure range, only the central part became a donut-shaped discoloration area where no discoloration was observed. This is because the secondary cavitation bubble force prevented the effective collapse of the bubble group and caused a large pressure to collect in the center. In addition, with respect to the output of low-frequency ultrasonic waves, the results showed that the area of the discoloration area gradually increased as the output was increased. This agrees very well with the characteristics shown in the results in Fig. 23, and indicates that control of the present technology can be performed by monitoring. Figure 24B is a cross-sectional view of the luminance distribution.In the middle sound pressure range of 400 mV, strong color development is seen in the center of the pressure-sensitive sheet, and in the high sound pressure range of 800 and 1000 mV, the color development in the center is weak. Is confirmed.

[0083] [C 13] Results of calculus breaking experiments in each sound pressure range

Finally, a model stone crushing experiment was performed in the high-frequency range where the high went. The results are shown in FIG. The result of crushing stones more efficiently in the middle sound pressure range than in the low and high sound pressure ranges was the result, confirming the previous studies.

 Industrial applicability

[0084] The present invention is also effective in industrial applications such as ultrasonic cleaning and cavitation 'Pyung, which are not limited to medical applications such as calculus crushing.

 Brief Description of Drawings

FIG. 1 is an overall system diagram of an ultrasonic irradiation apparatus.

 FIG. 2 shows a schematic diagram of a cavitation control method and an outline of an ultrasonic pulse waveform used for acoustic cavitation control.

 FIG. 3 shows the behavior of the cavitation when the acoustic cavitation using focused ultrasound is generated and collapsed using the above-described method.

 FIG. 4 is a diagram showing a result of applying the present method to a model stone.

 FIG. 5 is a view showing a configuration of a calculus breaking system according to the present invention.

 FIG. 6 is a flowchart of a calculus breaking method using the collapse pressure of a cavity.

 FIG. 7 is a diagram showing sound emitted from the cavitation cloud, where the horizontal axis is time and the vertical axis is sound pressure. (1) When the cloud is stabilized, the signal in the high frequency range changes. → Stable cloud monitoring is performed. (2) When the bubble cloud collapses, an impact pressure according to the strength of the collapse is observed. → The crushing efficiency is determined. (3) 100-200 residual air bubbles

After IX s, it collapses and a signal is detected. → Signal strength · The optimal repetition frequency is determined from the collapse time.

 FIG. 8A is a diagram showing a minimum output required for stable cloud cavitation. The vertical line A indicates the threshold (minimum applied voltage) of the occurrence of cavitation, and the vertical line B indicates the threshold (applied voltage) of the stable cloud cavitation. The applied voltage physically corresponds to the ultrasonic pressure amplitude on a one-to-one basis.

 FIG. 8B is a diagram showing a minimum irradiation time required for stable cloud cavitation. Vertical line

C indicates a stable cloud cavitation threshold (irradiation time).

 FIG. 9 is a flowchart illustrating a stable cloud calibration monitoring rig.

FIG. 10 is a diagram showing monitoring of collapse and disappearance of cavitation bubbles. [11] FIG. 11 is a diagram showing an ultrasonic irradiation / reception protocol.

FIG. 12 is a schematic diagram illustrating a sound wave receiving unit.

FIG. 13 is a schematic diagram of an experimental apparatus.

 FIG. 14 shows the classification of cavitation in the high frequency phase (high frequency pressure amplitude 4.8-11.7 [MPa]).

 [Fig. 15A] Shown is the representative length of the cavitation bubble group with respect to the ultrasonic irradiation time in the low sound pressure range of 4.7 [MPa]. 〇: Cloud cavitation with semi-elliptical sphere; ▲: Shielding cavitation that covers cloud cavitation with semi-elliptical sphere. In the low sound pressure range 4.7 [MPa], the bubble cloud has grown up! /, Na! / ,.

 [Fig. 15B] Shown is the representative length of the cavitation bubble group with respect to the ultrasonic irradiation time in the medium sound pressure range of 8.7 [MPa]. 〇: Cloud cavitation with semi-elliptical sphere; ▲: Shielding cavitation that covers cloud cavitation with semi-elliptical sphere. In the middle sound pressure range of 8.7 [MPa], it reaches a stable size after 130 [/ z s].

[15C] High sound pressure range 11.7 [MPa] Shows the representative length of the cavitation bubble group with respect to the ultrasonic irradiation time. 〇: Cloud cavitation of semi-elliptical sphere; ▲: Shielding cavitation covering cloud cavitation of semi-elliptical sphere. In the high sound pressure range of 11.7 [MPa], a large number of bubbles are generated immediately after the ultrasonic irradiation to cover the semi-elliptical spherical bubbles.

圆 16] The representative length of the cavitation bubble group with respect to the pressure amplitude of the high frequency ultrasonic wave (horizontal axis: pressure amplitude of high frequency ultrasonic wave, vertical axis: representative length of bubble group).

[FIG. 17A] Detection of emitted sound pressure at the occurrence of cavitation at each frequency of 1.7 [MHz].

 [FIG. 17B] Detection of emitted sound pressure when cavitation occurs at each frequency of 2.8 [MHz].

 [FIG. 17C] Detection of emitted sound pressure when cavitation occurs at each frequency of 3.9 [MHz].

圆 18A] Function generator output amplitude related to emission sound pressure in low sound pressure range

: Shows experimental results at 100, 200, 300 [mV]. 圆 18B] Function generator output amplitude related to the sound pressure emitted in the middle sound pressure range

: Experimental results at 400, 500, 600 [mV] are shown.

[18C] Function generator output amplitude related to sound pressure emitted in high sound pressure range

: 700,800 Shows the experimental results at 900,1000 [mV].

 [Figure 19] Example of monitoring the dynamics of cavitation using sound pressure waveform-1: Indicates the amplitude of the time-averaged waveform. (A) No signal is detected in the low sound pressure range. (B) In the medium sound pressure range, the amplitude of the time-average waveform takes a stable amplitude because the signal has the same amplitude and phase. (C) In the high sound pressure range, the magnitude of the pressure amplitude is reduced by canceling the irregular component.

 [Figure 20A] Example of monitoring the dynamics of cavitation using sound pressure waveform-2: Frequency analysis (FFT) is shown, corresponding to the low sound pressure range.

 [Figure 20B] Example of monitoring the dynamics of cavitation using sound pressure waveform-2: Frequency analysis (FFT) is shown, corresponding to the medium sound pressure range.

 [Figure 20C] Example of monitoring the dynamics of cavitation using sound pressure waveform-2: Frequency analysis (FFT) is shown, corresponding to the high sound pressure range.

圆 21] Indicates detection of collapse pressure in the low-frequency phase (upper row: raw waveform of received sound pressure, lower row: waveform after removal of low-frequency (555 [kHz]) component). In all cases, high-frequency ultrasonic waves have a medium sound pressure range of 9.5 [MPa] (maximum negative pressure), which is a condition for generating a stable shape and size of a semi-elliptical spherical cloud cavity. After the high frequency strike, the collapse pressure of the bubbles is observed during the reception of the low frequency reflected wave. It can also be seen that the received sound pressure of bubble group collapse has increased with the increase in low-frequency sound pressure.

 FIG. 22 shows the relationship between the cavitation bubbles generated in the high frequency phase and the collapse pressure in the low frequency phase.

 FIG. 23 shows an example of a database of collapse pressure with respect to the ultrasonic pressure amplitude of high frequency and low frequency.

[24A] Pressure-sensitive sheet experiment. FIG. 24A shows the experimental results for the high frequency and low frequency amplitudes.

FIG. 24B shows a pressure-sensitive sheet experiment. Figure 24B shows the luminance in the case of low frequency 26.6 [MPa]. It is a cross section of the distribution.

[25] The results of calculus crushing in each sound pressure range are shown. The left is “low sound pressure range”, the center is “medium sound pressure range”, and the right is “high sound pressure range”.

 [Fig. 26A] Cloud cavities of semi-elliptical spheres with stable size 'shapes created by focused ultrasound at various frequencies (1.67, 2.75, 3.27, 3.82 MHz).

FIG. 26B is a plot of the representative length of a cloud cavitation as shown in FIG. 26A versus frequency.

Claims

The scope of the claims

 [1] A first step of irradiating a high-frequency ultrasonic wave toward an object in which liquid is present in at least a part of its surroundings to generate cavitation bubbles in a region including the object; A second step of irradiating the object to collapse the cavitation bubbles and impart high energy to the object;

 A third step, which is an interval time after the second step,

 A first step having

 A second step of acquiring sound waves emitted from the cavitation bubbles and controlling the ultrasonic irradiation conditions by performing signal processing on the sound waves;

 Ultrasonic irradiation method having the following.

[2] In the method according to claim 1, in the third step of the first step, after the second step, do not irradiate the ultrasonic wave toward the object, or induce generation and growth of bubbles. However, an ultrasonic irradiation method characterized in that it is an interval time during which only an ultrasonic wave of a moderate intensity is irradiated.

 [3] The method according to any one of claims 1 and 2, wherein the second step can be performed at any time of the first, second and third steps of the first step. An ultrasonic irradiation method characterized by passively receiving a sound wave generated from the ultrasonic wave and receiving a sound wave reflected from the cavitation bubble with respect to Z or the irradiated ultrasonic wave.

 [4] The method according to any one of claims 1 to 3, wherein the signal processing of the second step includes determining whether or not a force has been generated by the first step of the first step to generate a stable cavitation bubble. An ultrasonic irradiation method characterized in that the ultrasonic irradiation conditions to be controlled are the output of high-frequency ultrasonic waves and Z or irradiation time.

 [5] The ultrasonic irradiation method according to claim 4, wherein the controlled ultrasonic irradiation condition further includes a frequency of a high-frequency ultrasonic wave.

[6] In the method according to any one of claims 4 and 5, the determination as to whether or not a force has generated a stable cavitation bubble is made based on the pressure amplitude and the Z or pressure of the sound wave reception signal from the cavitation bubble. An ultrasonic irradiation method using a size.

[7] In the method according to any one of claims 4 to 6, the determination as to whether or not a force has generated a stable cavitation bubble uses a frequency component of a received sound wave signal of the cavitation bubble force. An ultrasonic irradiation method, characterized in that:

 [8] The method according to any one of claims 4 to 7, wherein the determination as to whether or not the force has generated stable cavitation bubbles is performed by determining whether or not the generated cavitation bubbles are in the medium sound pressure range. Ultrasonic irradiation method.

 [9] In the method according to any one of claims 1 to 8, the signal processing in the second step is performed by checking whether the collapse position and / or collapse time of the cavitation bubble in the second step in the first step is appropriate. The ultrasonic irradiation method including determination and controlling the ultrasonic irradiation condition is positioning.

 [10] In the method according to claim 9, the determination as to whether the cavitation bubble collapse position and the Z or collapse time are appropriate is based on the transmission power of the low-frequency ultrasonic wave and the reception of the sound wave due to the collapse pressure. An ultrasonic irradiation method characterized by measuring time.

 [11] The method according to any one of claims 1 to 10, wherein the signal processing in the second step includes determining whether the collapse pressure of the cavitation bubbles in the second step in the first step is appropriate. The ultrasonic irradiation condition to be performed includes at least one of an output, a wave number, a rising time constant, a rising phase, and a frequency of a low-frequency ultrasonic wave.

 12. The ultrasonic irradiation method according to claim 11, wherein the ultrasonic irradiation conditions to be controlled further include at least one of irradiation conditions of high-frequency ultrasonic waves and positioning.

 [13] In the method according to any one of claims 11 and 12, the determination as to whether the collapse pressure of the cavitation bubble is appropriate is based on the pressure amplitude and Z or the magnitude of the pressure of the received sound wave signal due to the collapse pressure. An ultrasonic irradiation method characterized in that the method is carried out by measuring the temperature.

[14] In the method according to any one of claims 1 to 13, the signal processing in the second step includes controlling whether or not the residual bubbles in the third step in the first step are sufficiently small. An ultrasonic irradiation method, wherein the ultrasonic irradiation condition is a repetition frequency of the first step according to claim 1.

15. The ultrasonic irradiation method according to claim 14, wherein the determination is performed based on the collapse pressure and Z or collapse time of the residual bubbles.

[16] In the method according to claim 14, the determination is made based on the ultrasonic waves irradiated in the third step of the first step and having such an intensity that does not induce the generation and growth of bubbles. A method of irradiating ultrasonic waves, which is performed by receiving sound waves reflected from an object.

 17. The ultrasonic irradiation method according to claim 1, wherein the processing of the sound wave generated by the cavitation bubble force includes acquiring an image of the cavitation bubble based on the sound wave.

[18] The method according to any one of claims 1 to 17, wherein the method further comprises:

Z or an ultrasonic irradiation method including a step of acquiring a sound wave from an environment around a target object and performing signal processing.

[19] The method according to claim 18, wherein the signal processing is performed by using a signal of the object and Z or a sound wave from an environment around the object and the object and Z or a surrounding of the object. An ultrasonic irradiation method including obtaining an image.

[20] The ultrasonic irradiation method according to any one of claims 1 to 19, wherein the second step includes crushing an object.

[21] The ultrasonic irradiation method according to any one of claims 1 to 19, wherein the second step includes peeling of foreign matter from the object.

22. The ultrasonic irradiation method according to claim 1, wherein the second step includes a surface modification of the object.

23. The ultrasonic irradiation method according to claim 1, wherein the second step includes thermal denaturation of an object.

[24] an ultrasonic irradiator that irradiates the object with ultrasonic waves based on the set ultrasonic irradiation conditions;

 A sound wave receiving unit,

 A signal processing unit that processes a signal received by the sound wave receiving unit,

Having a control unit to control the ultrasonic irradiation conditions of the ultrasonic irradiation unit, The ultrasonic irradiation unit irradiates high-frequency ultrasonic waves toward an object in which liquid is present in at least a part of the surroundings by the control unit, and generates cavitation bubbles in a region including the object. Then, a low-frequency ultrasonic wave is irradiated toward the object to break down the cavitation bubbles and to control the object to apply high energy,

 The sound wave receiving unit receives the sound wave emitted by the cavitation bubble force, and processes the received sound wave by the signal processing unit, whereby the control unit controls the ultrasonic irradiation condition based on the signal processing result. An ultrasonic irradiation device characterized in that it is configured to perform

 [25] The ultrasonic irradiation apparatus according to claim 24, wherein the sound wave receiving unit is an ultrasonic probe and a Z or hide mouth phone.

 26. The ultrasonic irradiation apparatus according to claim 24, wherein the signal processing unit includes a sound pressure analyzing unit for a received sound wave.

 27. The ultrasonic irradiation apparatus according to claim 24, wherein the signal processing unit includes a frequency analysis unit for a received sound wave.

 [28] The apparatus according to any one of claims 23 to 27, further comprising means for irradiating ultrasonic waves having an intensity of about ヽ that does not induce the generation and growth of bubbles, and Alternatively, the ultrasonic irradiation apparatus is configured to process the reflected sound of the ultrasonic waves from the environment around the target object and the Z or cavitation bubbles in a sound wave receiving unit.

 29. The ultrasonic irradiation apparatus according to claim 24, wherein the signal processing unit includes an image processing unit that obtains image information based on a received sound wave.

 [30] The apparatus according to any one of claims 23 to 29, wherein the ultrasonic irradiation conditions include an output of the high-frequency ultrasonic wave, an irradiation time of the high-frequency ultrasonic wave, a frequency of the high-frequency ultrasonic wave, and an ultrasonic wave to the object. Ultrasound irradiation characterized by including one or more selected from the group consisting of positioning of irradiation part, repetition frequency, output of low frequency ultrasonic wave, wave number, time constant of rising, rising phase, and frequency apparatus.

31. The apparatus according to claim 30, wherein the apparatus has a storage unit, and the storage unit stores information indicating a relationship between the ultrasonic irradiation condition and a physical condition. Features Ultrasonic irradiation equipment.