JP4547580B2 - Ultrasonic irradiation device - Google Patents

Description

  The present invention relates to an ultrasonic irradiation apparatus that continuously and efficiently irradiates a substance with a high frequency at a high frequency.

As a transducer for irradiating an elastic wave, a piezoelectric transducer in a thickness vibration mode in which the driving frequency depends on the thickness of the piezoelectric substrate is widely used. This type of transducer has a problem that the operating frequency is single and it is difficult to obliquely enter ultrasonic waves in liquid. When a piezoelectric substrate whose thickness is sufficiently thick compared to the wavelength is in contact with the liquid, the interdigital transducer provided on the piezoelectric substrate functions as a leaky wave transducer at the interface between the liquid and the solid. It is possible to irradiate ultrasonic waves into the liquid. However, the leaky surface acoustic wave propagating through the piezoelectric substrate has only one mode without velocity dispersion. Therefore, this transducer has a problem that it is limited to operation in a single frequency band, and the direction of ultrasonic wave irradiation is limited to be perpendicular to the piezoelectric substrate or at a certain angle. Therefore, in order to enable adjustment of the irradiation angle and operation in a plurality of frequency bands, ultrasonic devices capable of sweeping ultrasonic waves into a substance with a small and light device configuration have been disclosed one after another (Patent Document 1). And 2). However, since these devices do not take into account the depth of the substance, it is difficult to irradiate ultrasonic waves that efficiently reach the bottom of the substance. Furthermore, since these devices do not assume that the device itself moves on the surface of a material whose depth changes, it is difficult to continue driving at a frequency optimum for the depth of the material.
JP 2001-309596 A JP 2001-309494 A

  In conventional ultrasonic devices, when irradiating ultrasonic waves into a substance, it is difficult to irradiate the ultrasonic waves that efficiently reach the bottom of the substance, and the device itself covers the surface of the substance whose depth changes. When moving, it was difficult to continue driving at the optimum frequency for the depth of the material.

The invention described in claim 1 is an ultrasonic irradiation apparatus comprising a piezoelectric substrate, an input interdigital transducer, an output interdigital transducer, at least one other interdigital transducer and an amplifier, the input interdigital transducer The interdigital electrode and the output interdigital electrode are arranged side by side in the vicinity of the center of the upper end surface of the piezoelectric substrate, and the interdigital electrode for irradiation is a periphery of the upper end surface of the piezoelectric substrate near the center. provided in part, to the input interdigital transducer, the frequency _{f i (i = 1, 2} , ..., n) each of the input electric signal E _i with (i = 1, 2, ... , n) simultaneously By being applied, a series of elastic waves corresponding to the input electric signal E _i is excited on the piezoelectric substrate, and the leakage components of the series of elastic waves are respectively irradiated into the material as longitudinal waves, A series of longitudinal waves reflected and reflected by the lower interface of the material One of out, is detected as delayed electric signal in interdigital transducer for the output, the delayed electric signal has one of said frequency f _i, the one of the frequency f _i, the Correlated to the distance between the lower interface of the material and the upper interface of the material, the delayed electrical signal is amplified by the amplifier and a portion of the amplified signal is again applied to the input interdigital electrode. Thus, a feedback-type delay line oscillator that is driven by the one of the frequencies f _i is configured, and the remainder of the amplified signal is applied to the irradiation interdigital electrode, whereby the piezoelectric substrate is applied. The elastic wave is excited, and the leakage component of the elastic wave is irradiated into the material as a longitudinal wave, reflected by the lower boundary surface of the material, and then re-reflected by the upper boundary surface of the material. Chained The above problem is solved by providing an ultrasonic irradiation apparatus characterized in that reflection occurs.

The invention according to claim 2 solves the above problem by providing a polymer film on the lower end surface of the piezoelectric substrate.

According to a third aspect of the present invention, a hole is provided between the input interdigital electrode and the output interdigital electrode of the piezoelectric substrate, or a shielding substance is fixed, thereby solving the above problem. To do.

The invention according to claim 4 solves the above-mentioned problem by a conductive shielding material being fixed between the input interdigital electrode and the output interdigital electrode of the piezoelectric substrate.

According to a fifth aspect of the present invention, the piezoelectric substrate is made of a piezoelectric polymer thin film or a piezoelectric ceramic thin plate, and the direction of the polarization axis of the piezoelectric ceramic thin plate is parallel to the thickness direction. Solve the problem.

According to a sixth aspect of the present invention, the input interdigital electrode and the output interdigital electrode have a regular electrode pattern or an arc-shaped electrode pattern, thereby solving the above problem.

According to a seventh aspect of the present invention, the interdigital transducer for irradiation has a regular electrode pattern or an arc-shaped electrode pattern, and the arc-shaped electrode pattern has an opening of the arc-shaped electrode pattern in the piezoelectric pattern. The problem is solved by being arranged so as to face the center of the upper end surface of the substrate.

According to an eighth aspect of the present invention, the interdigital transducer for irradiation has a regular electrode pattern or an arc-shaped electrode pattern, and the arc-shaped electrode pattern has an opening in the arc-shaped electrode pattern that is the piezoelectric pattern. The above-described problem is solved by arranging the back so as to face the center of the upper end surface of the substrate.

The invention according to claim 9 is characterized in that the input interdigital electrodes, the output interdigital electrodes, and the irradiation interdigital electrodes have a regular electrode pattern, and the length of the electrode fingers of the interdigital electrodes for irradiation. This solves the above problem by being longer than the length of the electrode fingers of the input and output interdigital electrodes.

The input interdigital electrode, the output interdigital electrode, and the irradiation interdigital electrode have a regular electrode pattern, and the direction of the electrode finger of the interdigital electrode for irradiation Solves the above problem by having an inclination with respect to the direction of the electrode fingers of the interdigital electrodes for input and output.

The invention described in claim 11 is characterized in that the input interdigital electrode, the output interdigital electrode, and the irradiation interdigital electrode have a dispersive electrode pattern in which an electrode period length is gradually changed. Solve the problem.

The invention according to claim 12 is characterized in that the input interdigital electrode and the output interdigital electrode are arranged such that the electrode fingers at one end involved in the maximum electrode period length in the input and output interdigital electrodes are The problem is solved by being arranged so as to approach each other.

The invention according to claim 13 is an ultrasonic irradiation apparatus in which a modulator is connected between the amplifier and the interdigital transducer for irradiation, and a message signal is input to the modulator, and the amplified signal Is input as a carrier signal, the amplitude of the carrier signal is modulated in accordance with the message signal to generate an AM signal, and the AM signal is applied to the irradiation interdigital electrode. The above-described problem is solved by providing an apparatus.

The invention according to claim 14 is an ultrasonic irradiation apparatus provided with at least two of the interdigital electrodes for irradiation, wherein at least two of the interdigital electrodes for irradiation are the center of the upper end surface of the piezoelectric substrate. On the other hand, the said subject is solved by providing the ultrasonic irradiation apparatus arrange | positioned so that it may become point symmetrical.

According to the present invention, it is possible to irradiate ultrasonic waves that efficiently reach the bottom of a substance with a small and lightweight device configuration, and when the device itself moves on the surface of a substance having a varying depth, Since it is possible to change the irradiation angle and frequency of the ultrasonic wave depending on the depth of the substance, it is possible to continue driving at the optimum frequency for the depth of the substance. As a result, it is possible to reflect ultrasonic waves in a chain manner inside the substance, and therefore it is possible to keep the inside of the substance always filled with ultrasonic energy.
In the present invention, a feedback type delay line oscillator is configured to simplify the circuit configuration and enable low power consumption driving, as well as a device that can cope with environmental changes such as temperature changes. It becomes possible to provide.
According to the present invention, it is also possible to irradiate the cytoplasm with ultrasonic waves through the skin, and the effect is exhibited when used on the head, face, gums and other parts. In addition, it can be applied to hydroponics, and it is effective for growing plants and promoting germination. In addition, according to the present invention, music or the like can be passed through a substance.

The ultrasonic irradiation apparatus of the present invention has a simple structure including a piezoelectric substrate, an interdigital transducer for input, an interdigital transducer for output, at least one other interdigital transducer for irradiation, and an amplifier.

FIG. 1 is a plan view of a first embodiment of the ultrasonic irradiation apparatus of the present invention as viewed from above. In this embodiment, a piezoelectric substrate 1, an input interdigital electrode 2, an output interdigital electrode 3, four irradiation interdigital electrodes (T ₁ , T ₂ , T ₃ and T ₄ ), an amplifier 4 and a polymer film 5 are used. Consists of. The polymer film 5 is not drawn in FIG. In this embodiment, four interdigital electrodes for irradiation (T ₁ , T ₂ , T ₃ and T ₄ ) are used, but one interdigital electrode for irradiation (T ₁ , T ₂ , T ₃ or It is also possible to use only T ₄ ). The input interdigital electrode 2 and the output interdigital electrode 3 are made of an aluminum thin film, have a regular electrode pattern, and are arranged in the vicinity of the center of the upper end surface of the piezoelectric substrate 1. The interdigital transducers (T ₁ , T ₂ , T ₃ and T ₄ ) are made of an aluminum thin film, have a regular electrode pattern, and are provided on the upper end surface of the piezoelectric substrate 1 at the periphery near the center. ing. The length of the electrode fingers of the irradiation interdigital electrodes (T ₁ , T ₂ , T ₃ and T ₄ ) is longer than the length of the electrode fingers of the input interdigital electrodes 2 and the output interdigital electrodes 3. The direction of the electrode fingers of the irradiation interdigital electrodes (T ₁ and T ₃ ) is orthogonal to the direction of the electrode fingers of the input interdigital electrodes 2 and the output interdigital electrodes 3, but the irradiation interdigital electrodes ( The direction of the electrode fingers of T ₂ and T ₄ ) is parallel to the direction of the electrode fingers of the input interdigital electrode 2 and the output interdigital electrode 3. In this way, the interdigital transducers (T ₁ , T ₂ , T ₃ and T ₄ ) are arranged so as to be point-symmetric with respect to the center of the upper end surface of the piezoelectric substrate 1. Of course, it is possible to arrange them so as not to be point-symmetric.

2 is a cross-sectional view of the ultrasonic irradiation apparatus of FIG. In FIG. 2, the interdigital transducers (T ₁ and T ₃ ) and the amplifier 4 are not drawn. The piezoelectric substrate 1 is made of a piezoelectric ceramic thin plate having a thickness of 220 μm, and a hole is provided in the center. In this embodiment, a piezoelectric ceramic thin plate is used as the piezoelectric substrate 1, but a piezoelectric polymer thin film can also be used. The lower end surface of the piezoelectric substrate 1 is covered with a polymer film made of silicon rubber. The input interdigital electrode 2, the output interdigital electrode 3 and the irradiation interdigital electrode (T ₁ , T ₂ , T ₃ and T ₄ ) have an electrode period length of 340 μm. In this way, the ultrasonic irradiation apparatus of FIG. 1 has a small, light and simple device configuration.

In the ultrasonic irradiation apparatus of FIG. 1, each input electric signal E _i (i = 1, 2,..., N) having a frequency f _i (i = 1, 2,..., N) is applied to the interdigital electrode 2 for input. By applying them simultaneously, a series of elastic waves corresponding to the input electric signal E _i is excited on the piezoelectric substrate 1. At this time, the piezoelectric substrate 1 is formed of a piezoelectric ceramic thin plate, and the direction of the polarization axis thereof is parallel to the thickness direction, whereby elastic waves are efficiently excited in the piezoelectric substrate 1. Each elastic wave consists of a leakage component and a non-leakage component. The non-leakage component does not propagate to the output interdigital electrode 3 because the hole is provided between the input interdigital electrode 2 and the output interdigital electrode 3. That is, this hole plays a role of blocking the propagation of non-leakage components. Therefore, instead of providing a hole in the piezoelectric substrate 1, it is also effective to fix a conductive shielding material such as a conductive paint. Further, an epoxy resin or the like can be substituted for the conductive paint.

FIG. 3 is a partial cross-sectional view of the ultrasonic irradiation apparatus of FIG. A leakage component of a series of elastic waves excited on the piezoelectric substrate 1 is irradiated as a longitudinal wave into the substance, for example, into the cytoplasm in contact with the polymer film 5. At this time, by using the polymer film 5, longitudinal waves can be irradiated into the cytoplasm with high efficiency. A series of longitudinal waves irradiated into the cytoplasm is reflected by a lower boundary surface of the cytoplasm, for example, a boundary surface between the cytoplasm and bone, teeth, air, or the like. Since these series of longitudinal waves have irradiation angles corresponding to the frequencies f _i (i = 1, 2,..., N), they are reflected according to the irradiation angles even when reflected at the lower boundary surface. Will have corners. The longitudinal wave path in the cytoplasm is indicated by, for example, three arrows in FIG. From Figure 3, in one of the output interdigital transducer 3 of the reflected longitudinal wave, it can be seen that are detected as delayed electric signal having one of frequencies f _i.

In the ultrasonic irradiation apparatus of FIG. 1, the delayed electrical signal detected by the output interdigital electrode 3 is amplified via the amplifier 4. A part of the amplified signal is input to the interdigital transducer 2 again. In this manner, the input interdigital transducer 2, the output interdigital electrode 3 and the amplifier 4, the delay line oscillator feedback type driven by one consists of the frequency f _i. Such a configuration of the delay line oscillator not only promotes reduction in size and weight of the device, but also realizes a device that can be driven with low power consumption and can cope with environmental changes such as temperature changes. On the other hand, the remainder of the amplified signal is input to the irradiation interdigital electrodes (T ₁ , T ₂ , T ₃ and T ₄ ), and _four elastic waves are excited on the piezoelectric substrate 1. Each elastic wave consists of a leakage component and a non-leakage component.

FIG. 4 is another partial cross-sectional view of the ultrasonic irradiation apparatus of FIG. The leakage components of the four elastic waves corresponding to the interdigital electrodes (T ₁ , T ₂ , T _3, and T ₄ ) are irradiated into the material as longitudinal waves and reflected on the lower boundary surface of the material. , Re-reflected by the upper boundary surface of the material. In this way, chain reflection occurs. Such chain reflection makes it possible to fill the substance with ultrasonic energy.

FIG. 5 is still another partial sectional view of the ultrasonic irradiation apparatus of FIG. As described above, a series of longitudinal waves from the input interdigital electrode 2 are reflected respectively at the lower boundary surface of the material, as shown in FIG. 3, and one of the reflected series of longitudinal waves is The output interdigital electrode 3 detects the delayed electric signal. At this time, the longitudinal wave detected as the delayed electrical signal in the output interdigital electrode 3 has a reflection angle that correlates with the distance between the lower boundary surface and the upper boundary surface of the substance. The path of the longitudinal wave when the distance between the lower boundary surface and the upper boundary surface is changed is indicated by, for example, three arrows in FIG. From FIG. 5, it can be seen that even if the distance between the lower boundary surface and the upper boundary surface changes, one reflected longitudinal wave is always detected as a delayed electric signal at the output interdigital electrode 3. In other words, regardless of the depth of the material, longitudinal waves corresponding to one is always detected at the output interdigital transducer 3 of the frequency f _i. Thus, according to the ultrasonic irradiation apparatus of FIG. 1, it becomes possible to change the drive frequency and the irradiation angle of a longitudinal wave according to the depth of a substance. Therefore, even when the ultrasonic irradiation device itself moves on the surface of the substance, even when the depth of the substance changes as it moves, for example, when it moves over the skin where the thickness of the cytoplasm changes as it moves, it is always optimal. It is possible to drive at a different frequency.

Thus, according to the ultrasonic irradiation apparatus of FIG. 1, it is possible to efficiently irradiate longitudinal waves into the cytoplasm regardless of the thickness of the cytoplasm. Therefore, the ultrasonic irradiation apparatus of FIG. 1 is effective for body massage, for example, massage of the head, face, gums and other parts and blood circulation promotion, and can also be applied to hydroponics. It is also effective for nurturing and promoting germination.

FIG. 6 is a plan view of the second embodiment of the ultrasonic irradiation apparatus of the present invention as viewed from above. This embodiment has the same structure as that shown in FIG. 1 except for the arrangement of the interdigital electrodes (T ₁ , T ₂ , T ₃ and T ₄ ) for irradiation. The direction of the electrode fingers of the irradiation interdigital electrodes (T ₁ , T ₂ , T ₃ and T ₄ ) is inclined with respect to the direction of the electrode fingers of the input interdigital electrodes 2 and the output interdigital electrodes 3. In this way, the interdigital transducers (T ₁ , T ₂ , T ₃ and T ₄ ) are arranged so as to be point-symmetric with respect to the center of the upper end surface of the piezoelectric substrate 1. Of course, it is possible to arrange them so as not to be point-symmetric.

In the ultrasonic irradiation apparatus of FIG. 6, the irradiation directions of the four longitudinal waves corresponding to the irradiation interdigital electrodes (T ₁ , T ₂ , T ₃ and T ₄ ) are all from the input interdigital electrode 2. It is different from the irradiation direction of a series of longitudinal waves to be irradiated. On the other hand, in FIG. 1, the irradiation directions of four longitudinal waves corresponding to the interdigital electrodes for irradiation (T ₁ , T ₂ , T ₃ and T ₄ ) are a series of vertical beams irradiated from the interdigital electrodes 2 for input. The direction of wave irradiation is not necessarily different. In this way, in the ultrasonic irradiation apparatus of FIG. 6, the delayed electrical signal with less noise is detected at the output interdigital electrode 3 as compared with FIG. 1.

FIG. 7 is a plan view of the third embodiment of the ultrasonic irradiation apparatus of the present invention as viewed from above. In this embodiment, a modulator 6 is newly provided, and an input interdigital electrode 7 and an output interdigital electrode 8 are provided in place of the input interdigital electrode 2 and the output interdigital electrode 3, respectively. And an interdigital transducer (T ₅ , T ₆ , T ₇ and T ₈ ) is provided in place of the interdigital transducer (T ₁ , T ₂ , T ₃ and T ₄ ). The structure is the same as that shown in FIG. The interdigital electrode 7 for input, the interdigital electrode 8 for output, and the interdigital electrode for irradiation (T ₅ , T ₆ , T ₇ and T ₈ ) have a regular electrode pattern and dispersion in which the electrode period length gradually changes. Each has a composite type pattern having both properties of the type electrode pattern, and its electrode period length is 285 to 380 μm. In the distributed electrode pattern, the distance between the two electrode fingers gradually changes, and the distance between the electrode finger on one end and the adjacent electrode finger becomes the maximum. Of course, the electrode fingers are involved in the maximum electrode period length, but the input interdigital electrode 7 and the output interdigital electrode 8 are the maximum electrodes in the input interdigital electrode 7 and the output interdigital electrode 8, respectively. The electrode fingers at one end involved in the cycle length are arranged so as to approach each other.

In the ultrasonic irradiation apparatus of FIG. 7, it is possible to supply an input electrical signal in a wide frequency band to the interdigital electrodes 7 by adopting a distributed electrode pattern. The frequency band of the input electric signal supplied to the input interdigital electrode 7 is considerably wider than that of the input electric signal supplied to the input interdigital electrode 2, and accordingly, the longitudinal wave irradiated from the input interdigital electrode 7 The irradiation angle is also considerably wider than the irradiation angle of the longitudinal wave irradiated from the interdigital transducer 2 for input.

FIG. 8 is a partial cross-sectional view of the ultrasonic irradiation apparatus of FIG. The path of the longitudinal wave when the distance between the lower boundary surface and the upper boundary surface is changed is indicated by, for example, four arrows in FIG. 8 also shows that one reflected longitudinal wave is always detected at the output interdigital electrode 8 as a delayed electrical signal, as in FIG. However, the irradiation angle of the longitudinal wave is considerably wide as compared with FIG. That is, by adopting a dispersive electrode pattern, it is possible to irradiate a longitudinal wave having an irradiation angle over a wide range from the interdigital electrode 7 for input, as well as the interdigital electrode 7 for input and the output electrode. By arranging the interdigital electrodes 8 so that the electrode fingers at one end involved in the maximum electrode cycle length in each approach each other, it is possible to increase the longitudinal waves that can be detected in the output interdigital electrodes 8. Become.

In the ultrasonic irradiation apparatus of FIG. 7, the delayed electrical signal detected by the output interdigital electrode 8 is amplified via the amplifier 4. A part of the amplified signal is input again to the interdigital electrode 7 for input. In this way, the input interdigital electrode 7, the output interdigital electrode 8, and the amplifier 4 constitute a feedback type delay line oscillator. On the other hand, the remainder of the amplified signal is input to the modulator 6 as a carrier signal. At this time, when a message signal that can be heard by human ears is input to the modulator 6, the amplitude of the carrier signal is modulated in accordance with the message signal, and as a result, an AM signal is generated. In this way, when the AM signal is applied to the interdigital transducers (T ₅ , T ₆ , T ₇ and T ₈ ), four elastic waves are efficiently excited on the piezoelectric substrate 1. The leakage component of each elastic wave is irradiated into the material as a longitudinal wave, reflected by the lower boundary surface of the material, and then re-reflected by the upper boundary surface of the material. In this way, chain reflection occurs. Therefore, according to the ultrasonic irradiation apparatus of FIG. 7, it becomes possible to effectively transmit a message signal such as music to a substance, for example, a liquid in which a plant is growing.

FIG. 9 is a plan view of the fourth embodiment of the ultrasonic irradiation apparatus of the present invention as viewed from above. This embodiment has the same structure as that shown in FIG. 7 except for the arrangement of the interdigital electrodes (T ₅ , T ₆ , T ₇ and T ₈ ) for irradiation. In the same manner as in FIG. 6, the direction of the electrode fingers of the irradiation interdigital electrodes (T ₅ , T ₆ , T ₇ and T ₈ ) is the direction of the input interdigital electrodes 7 and the output interdigital electrodes 8. With a slope. In this way, the irradiation interdigital electrodes (T ₅ , T ₆ , T ₇ and T ₈ ) are arranged so as to be point-symmetric with respect to the center of the upper end surface of the piezoelectric substrate 1. Of course, it is possible to arrange them so as not to be point-symmetric. In this manner, in the ultrasonic irradiation apparatus of FIG. 9, the delayed electrical signal with less noise is detected at the output interdigital electrode 3 as compared with FIG. 7.

FIG. 10 is a plan view of the fifth embodiment of the ultrasonic irradiation apparatus of the present invention as viewed from above. In this embodiment, the piezoelectric substrate 9 is used instead of the piezoelectric substrate 1, and the input interdigital electrode 10 and the output interdigital electrode 11 instead of the input interdigital electrode 2 and the output interdigital electrode 3. Are provided, and instead of the irradiation interdigital electrodes (T ₁ , T ₂ , T ₃ and T ₄ ), the irradiation interdigital electrodes (T ₉ , T ₁₀ , T ₁₁ and T ₁₂ ) are provided, respectively. Except for the above, it has the same structure as FIG. A conductive shielding material 12 made of conductive paint is fixed to the center of the upper end surface of the piezoelectric substrate 9. Input interdigital transducer 10, the output interdigital transducer 11 and the irradiation IDT (T _9, T _10, T ₁₁ and _{T 12)} is made of an aluminum thin film, it has an arc-shaped electrode pattern. This arc-shaped electrode pattern has an opening angle of 90 ° and an electrode cycle length of 340 μm. The interdigital electrodes (T ₉ , T ₁₀ , T ₁₁ and T ₁₂ ) for irradiation are arranged so that the opening of the arc-shaped electrode pattern faces the center of the upper end surface of the piezoelectric substrate 9. In this way, the interdigital transducers (T ₉ , T ₁₀ , T ₁₁ and T ₁₂ ) are arranged so as to be point-symmetric with respect to the center of the upper end surface of the piezoelectric substrate 9. Of course, it is possible to arrange them so as not to be point-symmetric.

In the ultrasonic irradiation apparatus of FIG. 10, a series of elastic waves are excited on the piezoelectric substrate 9 by supplying the input electrical signal E _i having the frequency f _i to the interdigital electrode 10 for input. It plays the role of blocking the propagation of non-leakage components of these elastic waves. The ultrasonic irradiation apparatus of FIG. 10 has an input interdigital transducer of FIG. 1 in which the irradiation direction of longitudinal waves irradiated from the interdigital transducer 10 and the interdigital transducers (T ₉ , T ₁₀ , T ₁₁ and T ₁₂ ). The same function as in FIG. 1 is achieved except that the irradiation direction of the longitudinal wave irradiated from the electrode 2 and the interdigital transducers (T ₁ , T ₂ , T ₃ and T ₄ ) is different.

FIG. 11 is a plan view of the sixth embodiment of the ultrasonic irradiation apparatus of the present invention as viewed from above. This example has the same structure as that of FIG. 10 except for the arrangement of the interdigital electrodes (T ₉ , T ₁₀ , T _11, and T ₁₂ ) for irradiation. The interdigital electrodes (T ₉ , T ₁₀ , T _11, and T ₁₂ ) for irradiation are arranged such that the opening of the arc-shaped electrode pattern faces the center of the upper end surface of the piezoelectric substrate 9. In this way, the interdigital transducers (T ₉ , T ₁₀ , T ₁₁ and T ₁₂ ) are arranged so as to be point-symmetric with respect to the center of the upper end surface of the piezoelectric substrate 9. Of course, it is possible to arrange them so as not to be point-symmetric. The ultrasonic irradiation apparatus of FIG. 11 is the same as that of FIG. 10 except that the irradiation direction of longitudinal waves emitted from the interdigital electrodes (T ₉ , T ₁₀ , T _11, and T ₁₂ ) is different from that of FIG. Performs similar functions.

FIG. 12 is a plan view of the seventh embodiment of the ultrasonic irradiation apparatus of the present invention as viewed from above. In this embodiment, instead of the input interdigital electrode 10 and the output interdigital electrode 11, an input interdigital electrode 13 and an output interdigital electrode 14 are provided, and an irradiation interdigital electrode (T ₉ , T ₁₀ , T _11, and T ₁₂ ) have the same structure as that shown in FIG. 10 except that an interdigital transducer for irradiation (T ₁₃ , T _14, and T ₁₅ ) is provided. The interdigital electrode 13 for input, the interdigital electrode 14 for output, and the interdigital electrode for irradiation (T ₁₃ , T ₁₄ and T ₁₅ ) are arc-shaped electrode patterns having an opening angle of 120 ° and electrodes of 285 to 380 μm. Each has a composite pattern having both properties of a dispersive electrode pattern having a periodic length. In the distributed electrode pattern, the distance between the two electrode fingers gradually changes, and the distance between the electrode finger on one end and the adjacent electrode finger becomes the maximum. Of course, the electrode fingers are involved in the maximum electrode cycle length. The input interdigital electrodes 13 and the output interdigital electrodes 14 are the maximum electrodes in the input interdigital electrodes 13 and the output interdigital electrodes 14, respectively. The electrode fingers at one end involved in the cycle length are arranged so as to approach each other. The ultrasonic irradiation apparatus of FIG. 12 has an input interdigital electrode 7 shown in FIG. 7 in which the irradiation direction of longitudinal waves emitted from the input interdigital electrode 13 and the interdigital irradiation electrodes (T ₁₃ , T ₁₄ and T ₁₅ ). The same function as that of FIG. 7 is achieved except that the irradiation direction of the longitudinal wave irradiated from the interdigital electrodes (T ₅ , T ₆ , T ₇ and T ₈ ) is different.

FIG. 13 is a plan view of the eighth embodiment of the ultrasonic irradiation apparatus of the present invention as viewed from above. This embodiment has the same structure as that shown in FIG. 12 except that an input interdigital electrode 7 and an output interdigital electrode 8 are provided in place of the input interdigital electrode 13 and the output interdigital electrode 14. Have The ultrasonic irradiation apparatus of FIG. 13 performs the same function as FIG. 12 except that the irradiation direction of the longitudinal wave irradiated from the interdigital transducer 7 is the same as that of FIG.

The top view when the 1st Example of the ultrasonic irradiation apparatus of the present invention is seen from the upper part 1 is a cross-sectional view of the ultrasonic irradiation apparatus of FIG. Partial sectional view of the ultrasonic irradiation apparatus of FIG. Another partial cross-sectional view of the ultrasonic irradiation apparatus of FIG. Still another partial cross-sectional view of the ultrasonic irradiation apparatus of FIG. The top view when the 2nd Example of the ultrasonic irradiation apparatus of this invention is seen from upper direction The top view when the 3rd example of the ultrasonic irradiation device of the present invention is seen from the upper part Partial sectional view of the ultrasonic irradiation apparatus of FIG. The top view when the 4th example of the ultrasonic irradiation device of the present invention is seen from the upper part The top view when the 5th example of the ultrasonic irradiation apparatus of the present invention is seen from the upper part The top view when the 6th example of the ultrasonic irradiation device of the present invention is seen from the upper part The top view when the 7th Example of the ultrasonic irradiation apparatus of this invention is seen from upper direction The top view when the 8th example of the ultrasonic irradiation apparatus of the present invention is seen from the upper part

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Piezoelectric substrate 2 Input interdigital electrode 3 Output interdigital electrode 4 Amplifier 5 Polymer film 6 Modulator 7 Input interdigital electrode 8 Output interdigital electrode 9 Piezoelectric substrate 10 Input interdigital electrode
11 Interdigital electrode for output 12 Conductive shielding material 13 Interdigital electrode for input 14 Interdigital electrode for output
_{T 1, T 2, T 3} , T 4 irradiated IDT
_{T 5, T 6, T 7} , T 8 irradiated IDT
_{T 9, T 10, T 11} , T 12 irradiated IDT
Interdigital electrode for T ₁₃ , T ₁₄ , T ₁₅ irradiation

Claims (14)

An ultrasonic irradiation apparatus comprising a piezoelectric substrate, an input interdigital electrode, an output interdigital electrode, at least one other interdigital electrode and an amplifier, wherein the input interdigital electrode and the output interdigital electrode Are arranged side by side in the vicinity of the center of the upper end surface of the piezoelectric substrate, and the interdigital electrodes for irradiation are provided in the periphery of the upper end surface of the piezoelectric substrate in the vicinity of the center. Each input electric signal E _i (i = 1, 2,..., N) having a frequency f _i (i = 1, 2,..., N) is simultaneously applied to the interdigital electrodes, thereby the input electric signal. A series of elastic waves corresponding to the signal E _i is excited on the piezoelectric substrate, and the leakage components of the series of elastic waves are each reflected as a longitudinal wave in the substance and then reflected by the lower boundary surface of the substance, One of the reflected series of longitudinal waves is Detected in use interdigital transducer as a delayed electric signal, said delayed electric signal has one of said frequency f _i, said one of said frequency f _i is said lower boundary surface of the material Correlated to the distance between the upper boundary surfaces of the substance, the delayed electrical signal is amplified by the amplifier, and a part of the amplified signal is again applied to the interdigital electrode for input, so that the frequency f A feedback type delay line oscillator driven by the one of _i is configured, and by applying the remainder of the amplified signal to the irradiation interdigital electrode, an elastic wave is excited in the piezoelectric substrate, The leakage component of the elastic wave is irradiated into the material as a longitudinal wave, reflected by the lower boundary surface of the material, and then re-reflected by the upper boundary surface of the material, thereby causing chained reflection. Features An ultrasonic irradiation device. The ultrasonic irradiation apparatus according to claim 1, wherein a polymer film is provided on a lower end surface of the piezoelectric substrate. The ultrasonic irradiation apparatus according to claim 1, wherein a hole is provided between the input interdigital electrode and the output interdigital electrode of the piezoelectric substrate, or a shielding substance is fixed. The ultrasonic irradiation apparatus according to claim 1, wherein a conductive shielding material is fixed between the input interdigital electrode and the output interdigital electrode of the piezoelectric substrate. The super substrate according to claim 1, 2, 3, or 4, wherein the piezoelectric substrate is made of a piezoelectric polymer thin film or a piezoelectric ceramic thin plate, and a direction of a polarization axis of the piezoelectric ceramic thin plate is parallel to a thickness direction thereof. Sonic irradiation device. The ultrasonic irradiation apparatus according to claim 1, wherein the input interdigital electrode and the output interdigital electrode have a regular electrode pattern or an arc-shaped electrode pattern. The interdigital transducer for irradiation has a regular electrode pattern or an arc-shaped electrode pattern, and the arc-shaped electrode pattern has an opening of the arc-shaped electrode pattern facing the center of the upper end surface of the piezoelectric substrate. The ultrasonic irradiation apparatus according to claim 1, arranged as described above. The irradiation interdigital electrode has a regular electrode pattern or an arc-shaped electrode pattern, and the arc-shaped electrode pattern has an opening of the arc-shaped electrode pattern in the back of the center of the upper end surface of the piezoelectric substrate. The ultrasonic irradiation apparatus according to claim 1, wherein the ultrasonic irradiation apparatus is disposed so as to face. The input interdigital electrode, the output interdigital electrode, and the irradiation interdigital electrode have regular electrode patterns, and the length of the electrode finger of the irradiation interdigital electrode is the input and output The ultrasonic irradiation apparatus according to claim 1, wherein the ultrasonic irradiation apparatus is longer than the length of the electrode finger of the interdigital electrode. The interdigital electrodes for input, the interdigital electrodes for output, and the interdigital electrodes for irradiation have regular electrode patterns, and the direction of the electrode fingers of the interdigital electrodes for irradiation is the interdigital for input and output The ultrasonic irradiation apparatus of Claim 1 which has inclination with respect to the direction of the electrode finger of a electrode. 2. The ultrasonic irradiation apparatus according to claim 1, wherein the input interdigital electrode, the output interdigital electrode, and the irradiation interdigital electrode have a dispersive electrode pattern in which an electrode cycle length gradually changes. The interdigital electrodes for input and the interdigital electrodes for output are arranged such that electrode fingers at one end involved in the maximum electrode period length in the input and output interdigital electrodes approach each other. Item 12. The ultrasonic irradiation apparatus according to Item 11. An ultrasonic irradiation apparatus in which a modulator is connected between the amplifier and the interdigital transducer for irradiation, and a message signal is input to the modulator and the remaining portion of the amplified signal is input as a carrier signal. 2. The ultrasonic irradiation apparatus according to claim 1, wherein the amplitude of the carrier signal is modulated according to the message signal to generate an AM signal, and the AM signal is applied to the irradiation interdigital electrode. An ultrasonic irradiation apparatus provided with at least two interdigital electrodes for irradiation, wherein at least two interdigital electrodes for irradiation are point-symmetric with respect to the center of the upper end surface of the piezoelectric substrate. The ultrasonic irradiation apparatus according to claim 1 arranged.

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