Piezoelectric sensitive assembly and underwater acoustic array sensor thereof

Abstract

The invention discloses a piezoelectric sensitive assembly and an underwater acoustic array sensor thereof, and relates to the technical field of acoustic wave application. A plurality of piezoelectric sensing unit assemblies form the underwater acoustic array sensor according to a certain arrangement sequence, and the receiving sensitivity and the working bandwidth of the underwater acoustic sensor can be widened. The piezoelectric sensitive assembly comprises a substrate and a vibration lamination layer. The vibration lamination comprises at least one first sensing unit and at least one second sensing unit; the first sensing unit and the second sensing unit are geometrically interconnected through a geometric interconnection structure to form an integrated sensing unit assembly, and the sensing unit assemblies are all located on the substrate; the cross sections of the first sensitive unit and the second sensitive unit are different in size or thickness, and the cross sections are parallel to the substrate; sensitivity curves of the first sensing unit and the second sensing unit are mutually compensated and coupled, so that the receiving bandwidth is widened. The underwater acoustic array sensor provided by the invention can serve an underwater detection system, and has an important value for improving the measurement precision of a target and improving the detection effect.

Description

Technical Field

[0001] The present invention relates to the technical field of sound wave applications, and in particular to a piezoelectric sensitive component and an underwater acoustic array sensor thereof. Background Art

[0002] In the field of acoustic wave applications, underwater acoustics, as a key branch, has widespread application in both military and civilian fields, serving as an effective tool for detecting targets and transmitting information. Marine resource exploration, marine geomorphology mapping, fisheries, navigation, and communications all rely on underwater acoustic technology. Underwater acoustic transducers are key devices for transmitting and receiving underwater acoustic signals. These include drivers that convert electrical energy into mechanical energy, thereby emitting sound waves, and sensors that convert underwater acoustic energy into electrical energy, thereby detecting sound waves. In underwater acoustic detection applications, the sensor's receiving bandwidth and sound pressure sensitivity determine the detection resolution and range. A wider bandwidth results in a higher resolution, while a greater sensitivity increases the detection range.

[0003] Piezoelectric micromechanical sensors are devices that receive sound waves based on the direct piezoelectric effect of piezoelectric thin film materials. They offer advantages such as fast response, excellent sensitivity, lightweight design, and ease of integration. They have been widely studied in underwater acoustic applications, such as hydrophones. However, existing hydrophones often operate in a non-resonant state, resulting in low sensitivity and limited operating bandwidth, limiting their application in underwater acoustic detection and imaging. Summary of the Invention

[0004] The purpose of the present invention is to provide a piezoelectric sensitive component and an underwater acoustic array sensor thereof. A plurality of sensitive units of different sizes are formed into a piezoelectric sensitive unit component through a geometric interconnection structure. The plurality of piezoelectric sensitive unit components are arranged in a certain order to form an underwater acoustic array sensor, which can broaden the receiving sensitivity and working bandwidth of the underwater acoustic sensor.

[0005] To achieve the above object, the present invention provides the following technical solutions: In a first aspect, the present invention provides a piezoelectric sensitive component, comprising a substrate and a vibration stack; The vibration stack includes at least one first sensitive unit and at least one second sensitive unit; The first sensitive unit is geometrically interconnected with the second sensitive unit through a geometric interconnection structure to form an integrated sensitive unit component, and the components are located on the substrate; The cross-sectional dimensions or thicknesses of the first sensitive unit and the second sensitive unit are different, and the cross-sectional dimensions are parallel to the substrate; The sensitivity curves of the first sensitive unit and the second sensitive unit compensate and couple with each other.

[0006] Furthermore, by making the peak and / or trough position on the sensitivity curve of the first sensitive unit different from the trough and / or peak position on the sensitivity curve of the second sensitive unit, the sensitivity curves of the first sensitive unit and the second sensitive unit compensate and couple with each other, thereby widening the receiving bandwidth.

[0007] Furthermore, the first sensitive unit and the second sensitive unit each include a structural layer, at least one electrode layer and at least one piezoelectric layer; The electrode layer includes an upper electrode and a lower electrode; The structural layer serves as a support and carrier for the sensitive unit; When the sound wave is transmitted to the sensitive unit, the sensitive unit is deformed, the piezoelectric layer is polarized and charges are generated on the surface of the upper and lower electrodes respectively, and electrical signals are output through the upper and lower electrodes. The output electrical signals are used for perception detection.

[0008] Further, the upper electrode includes at least one inner electrode and at least one outer electrode; When receiving sound waves, differential reception is adopted for at least one inner electrode and at least one outer electrode, thereby improving receiving sensitivity.

[0009] Furthermore, the first sensitive unit and the second sensitive unit further include a damping layer, a protective layer and other laminated layers.

[0010] Furthermore, the size of the first sensitive unit is larger than the size of the second sensitive unit, and the number of the first sensitive units is not greater than the number of the second sensitive units.

[0011] Furthermore, the size of the first sensitive unit and the cross-sectional shape of the second sensitive unit are both circular; or both are elliptical; or both are polygonal, and the number of sides of the polygon is not less than 4.

[0012] Furthermore, the geometric interconnection structure between the first sensitive unit and the second sensitive unit can be any shape, optionally including a rectangle, a broken line, an arc, etc., to achieve modal coupling between the first sensitive unit and the second sensitive unit and increase sensitivity.

[0013] Furthermore, at least one first sensitive unit and at least one second sensitive unit are distributed on the substrate in a centrally symmetrical manner to achieve symmetrical vibration and broaden the receiving bandwidth.

[0014] Furthermore, a plurality of cavities are provided on the substrate, and the first sensitive unit and the second sensitive unit are suspended above the corresponding cavities respectively to ensure that the diaphragms of the sensitive units have sufficient vibration space.

[0015] Furthermore, the first sensitive unit has a characteristic size a, the second sensitive unit has a characteristic size b, and a>b; Further, the distance between the centers of the first sensitive unit and the second sensitive unit is L, and a / 2 < L < a + b, such that under the premise of being affected by process limits, the coupling bandwidth is larger.

[0016] In a second aspect, the present invention further provides an underwater acoustic array sensor, which includes a piezoelectric sensitive component as described in any one of the above, and multiple piezoelectric sensitive components are distributed in at least one column.

[0017] Further, the number of first sensitive units in each piezoelectric sensitive component is the same, and the number of second sensitive units is also the same. The first sensitive units and the second sensitive units in each piezoelectric sensitive component are arranged in the same order.

[0018] Further, the piezoelectric sensitive components in every two adjacent columns of the underwater acoustic array sensor are arranged in a staggered manner, which can reduce the acoustic coupling crosstalk between adjacent micro sensors and improve the signal-to-noise ratio.

[0019] Further, the underwater acoustic array sensor further includes an acoustic impedance matching layer for adjusting the acoustic impedance difference between the sensitive component ( ), where ρ is the density, ), and the external medium ( [[ID=IS=18]]v is the sound speed), and increase the acoustic wave transmission efficiency. For ρ,

[0020] Further, the above acoustic impedance matching layer has at least one layer of acoustic impedance laminate, and the acoustic impedance values and thicknesses of different laminates are different; the acoustic impedance value ( of the middle laminate is the arithmetic square root of the acoustic impedances of two adjacent laminates, and the thickness is ; where is a non-zero positive integer, is the propagation wavelength of the acoustic wave in this laminate.

[0021] The beneficial effects of the present invention are as follows: A piezoelectric sensitive component provided by the present invention includes at least one first sensitive unit and at least one second sensitive unit. The first sensitive unit and the second sensitive unit are geometrically interconnected, and the cross-sectional dimensions of the first sensitive unit and the second sensitive unit are different, so as to achieve modal coupling between units to broaden the reception bandwidth and improve the sensitivity.

[0022] Further, multiple sensitive unit components are arranged according to a certain geometric relationship to form an underwater acoustic array sensor. By using the acoustic coupling effect, the low valley sound pressure of the sensitive component is enhanced through the acoustic coupling of the medium, thereby further broadening the bandwidth.

[0023] The underwater acoustic array sensor proposed by the present invention can serve an underwater detection system and has important value for improving the measurement accuracy of the target and enhancing the detection effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 This is a schematic structural diagram of a piezoelectric sensitive component proposed by the present invention; Figure 2 This is a top view of a piezoelectric sensitive component with a rectangular geometric interconnection structure proposed by the present invention. Figure 3 A top view of a piezoelectric sensitive component having an arc-shaped geometric interconnection structure according to the present invention; Figure 4 A top view of a piezoelectric sensitive component having a zigzag-line-shaped geometric interconnection structure according to the present invention; Figure 5 This is a schematic diagram of an independent sensitivity curve of a single sensitive unit according to the present invention; Figure 6 Schematic diagram of a sensitivity curve of a first sensitive unit and two second sensitive units coupled through a rectangular interconnection structure and a sensitivity curve without coupling through a geometric interconnection structure according to the present invention; Figure 7 This is a schematic structural perspective diagram of another cavity-type piezoelectric sensitive component according to the present invention; Figure 8 Schematic cross-sectional view of the cavity-type piezoelectric sensitive component of the present invention; Figure 9 Schematic cross-sectional view of the cavity micro-column piezoelectric sensitive component of the present invention; Figure 10 A schematic structural perspective view of another piezoelectric sensitive component with internal and external electrodes according to the present invention; Figure 11 This is a schematic structural diagram of another multi-circular piezoelectric sensitive component according to the present invention; Figure 12 This is a schematic structural diagram of another multi-elliptical piezoelectric sensitive component according to the present invention; Figure 13 This is a schematic structural diagram of another elliptical-circular combined piezoelectric sensitive component according to the present invention; Figure 14 This is a structural diagram of several array sensors described in the present invention, wherein Figure 14 (a) is a parallel type sensor. Figure 14(b) is a staggered sensor; Figure 15 Schematic diagram of the sensitivity curve of the 1×5 array of the present invention; Figure 16 This is a schematic structural diagram of an underwater acoustic detection device according to the present invention.

[0026] Among them, 11 represents the first sensitive unit, 12 represents the second sensitive unit, 13 represents the geometric interconnection structure, 101 represents the substrate, 102 represents the structural layer, 102-1 represents the substrate layer, 102-2 represents the physical functional layer, 103 represents the lower electrode, 104 represents the piezoelectric layer, 105 represents the upper electrode, 105-1 represents the outer electrode, 105-2 represents the inner electrode, 106 represents the protective layer, 107 represents the cavity, and 108 represents the microcolumn structure. DETAILED DESCRIPTION

[0027] In the following description, the specific implementation details of "a piezoelectric sensitive component and its underwater acoustic array sensor" provided in this specification are for illustrative purposes rather than restrictive definitions, and are intended to help those skilled in the art to thoroughly understand the principles and implementation of the invention; however, those skilled in the art should be clear that these details only represent one of the feasible embodiments, and the core concept of the invention can be fully realized by other technical means or workarounds that are not fully described without departing from its spirit, and the omission of details of conventional devices known in the art in the specification is to avoid redundant information interfering with the understanding of the innovation points. This does not mean that these known technologies are not required for implementation, and technical personnel should be able to supplement and apply them on their own based on professional knowledge.

[0028] The specific embodiments of the present invention are further described below in conjunction with the accompanying drawings. The following embodiments will help those skilled in the art further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that those skilled in the art may make various changes and improvements without departing from the scope of the present invention, and these are all within the scope of protection of the present invention.

[0029] Implementation Method 1: Combination Figure 1 、 Figure 5 and Figure 6 This embodiment provides a piezoelectric sensitive component as a device for receiving sound wave signals, such as Figure 1 As shown, the piezoelectric sensitive component includes a substrate 101 and a vibration stack; The vibration stack includes at least one first sensitive unit 11 and at least one second sensitive unit 12; The first sensitive unit 11 is geometrically interconnected with the second sensitive unit 12 via a geometric interconnection structure 13 to form an integrated sensitive unit assembly, and is located on the substrate 101; The cross-sectional dimensions or thicknesses of the first sensitive unit 11 and the second sensitive unit 12 are different, and the cross-sectional dimensions are parallel to the substrate 101 . The sensitivity curves of the first sensitive unit 11 and the second sensitive unit 12 compensate and couple with each other.

[0030] Specifically, if Figure 1 As shown, the first sensitive unit 11 and the second sensitive unit 12 each include a structural layer 102, at least one electrode layer and at least one piezoelectric layer 104; The electrode layer includes an upper electrode 105 and a lower electrode 103; The structural layer 102 serves as a support and carrier for the sensitive unit; When the sound wave is transmitted to the sensitive unit, the sensitive unit is deformed, the piezoelectric layer 104 is polarized and generates charges on the upper and lower electrode surfaces respectively, and outputs electrical signals through the upper and lower electrodes. The output electrical signals can be used to form a detection cloud map at the back end of the system, thereby completing the perception detection.

[0031] Furthermore, in some possible implementations, the size of the first sensitive unit 11 is larger than the size of the second sensitive unit 12 , and the number of the first sensitive units 11 is no more than the number of the second sensitive units 12 .

[0032] Furthermore, in some possible implementations, the cross-sectional shapes of the first sensitive unit 11 and the second sensitive unit 12 are both circular; or both elliptical; or both polygonal, and the number of sides of the polygon is not less than 4.

[0033] Furthermore, in some possible implementations, the cross-sectional dimensions or thicknesses of the first sensitive unit 11 and the second sensitive unit 12 are different, and the cross sections are both parallel to the substrate 101 ; Furthermore, in some possible implementations, the peak and / or trough positions on the sensitivity curve of the first sensitive unit can be different from the trough and / or peak positions on the sensitivity curve of the second sensitive unit, so that the sensitivity curves of the first sensitive unit and the second sensitive unit compensate and couple with each other, thereby broadening the receiving bandwidth.

[0034] The peak and / or trough position on the sensitivity curve of the first sensitive unit is different from the trough and / or peak position on the sensitivity curve of the second sensitive unit, including the following situations: Case 1: The peak and trough positions on the sensitivity curve of the first sensitive unit 11 are different from the trough and peak positions on the sensitivity curve of the second sensitive unit.

[0035] Case 2: The peak on the sensitivity curve of the first sensitive unit 11 and the peak on the sensitivity curve of the second sensitive unit 12 are at different positions, and the trough on the sensitivity curve of the first sensitive unit 11 and the trough on the sensitivity curve of the second sensitive unit 12 are at the same position.

[0036] Case 3: The peak on the sensitivity curve of the first sensitive unit 11 is at the same position as the peak on the sensitivity curve of the second sensitive unit 12 , and the trough on the sensitivity curve of the first sensitive unit 11 is at different positions from the trough on the sensitivity curve of the second sensitive unit 12 .

[0037] Figure 5 Shown are schematic diagrams of sound pressure sensitivity curves of the first sensitive unit 11 and the second sensitive unit 12; Figure 6 The figure shows a schematic diagram of the sound pressure sensitivity curve of the first sensitive unit 11 and the second sensitive unit 12 coupled, and the first sensitive unit 11 and the second sensitive unit 12 interconnected by a rectangular structure in this embodiment. Figure 5 The solid line shows the sensitivity curve of the first sensitive unit 11, and the dashed line shows the sensitivity curve of the second sensitive unit 12. There is a certain bandwidth difference between the first-order resonance peak position of the sensitivity curve of the first sensitive unit 11 and the first-order resonance peak position of the sensitivity curve of the second sensitive unit 12. Figure 6 As can be seen in the figure, when the first sensitive unit 11 and the second sensitive unit 12 are coupled (not coupled via a geometric interconnection structure), the sound pressure sensitivity curve of the resulting sensitive unit array (shown as a solid line) exhibits a significant trough due to the difference in the positions of the self-resonant frequencies of the two types of sensitive units, resulting in little effect on bandwidth broadening. However, the sensitive unit assembly described in this embodiment utilizes a geometric interconnection structure to structurally interconnect the first sensitive unit 11 and the second sensitive unit 12. By leveraging the modal coupling of the combined structure, it is possible to effectively compensate for the inherent response differences between the two types of sensitive units. This, in turn, compensates for the trough in the sensitivity curve of the discrete sensitive unit array, resulting in a wider reception bandwidth and overall sensitivity characteristics (shown as a dashed line).

[0038] Therefore, the piezoelectric sensitive component proposed in this embodiment includes at least one first sensitive unit and at least one second sensitive unit. The first sensitive unit and the second sensitive unit are geometrically interconnected, and the cross-sectional size of the first sensitive unit is different from the cross-sectional size of the second sensitive unit. Modal coupling between the units can be achieved to broaden the receiving bandwidth and improve sensitivity.

[0039] Implementation Method 2: Combination Figures 2 to 4 This embodiment is described as an example of a piezoelectric sensitive component structure described in the first embodiment above. like Figure 2As shown, the geometric interconnection structure 13 between the first sensitive unit 11 and the second sensitive unit 12 can be of any shape, including a rectangular shape ( Figure 2 shown), arc ( Figure 3 As shown), broken line ( Figure 4 As shown in FIG. 1 ), etc., to achieve modal coupling between the first sensitive unit 11 and the second sensitive unit 12. In addition, in some possible embodiments, the first sensitive unit 11 has a characteristic size a, and the second sensitive unit 12 has a characteristic size b, where a>b, and the center distance between the first sensitive unit 11 and the center of the second sensitive unit 12 is L, which can affect the modal coupling effect; the smaller L, the larger the coupling bandwidth, and is affected by the process limit; in this embodiment, the following is selected: a / 2 <L<a+b。

[0040] Implementation Method 3: Combination Figures 7 to 10 This embodiment is described as follows. This embodiment is an example of another structure of a piezoelectric sensitive component proposed in the first embodiment above. like Figure 7 As shown, it includes a substrate 101, a structural layer 102, a lower electrode 103, a piezoelectric layer 104, an upper electrode 105 and a protective layer 106. Optionally, as Figure 8 As shown, a plurality of cavities 107 are processed on the substrate 101 to release the sensitive diaphragm structure including the substrate above the cavity 107; optionally, as Figure 9 As shown, a micro-column structure 108 can also be processed in the cavity 107 structure, located below the sensitive diaphragm, to protect the diaphragm from bending deformation caused by stress. Figure 8 As shown, the structural layer 102 optionally includes a substrate layer 102 - 1 and a physical function layer 102 - 2 .

[0041] In practical applications, the materials for substrate 101 and underlayer 102-1 can be silicon wafers, glass sheets, or organic polymers. Etching is performed to form a cavity 107 structure or a cavity structure with micropillars in substrate 101, thereby releasing the diaphragm structure including the substrate above cavity 107. The physical function layer 102-2 can be a single or multilayer inorganic or organic polymer material, including silicon nitride, silicon oxide, aluminum nitride, polyimide, etc., and is used for electronic insulation and stress regulation within the diaphragm. The upper and lower electrodes are used to collect the electrical signals generated by the piezoelectric layer 104 under the action of sound waves. They can be various conductive materials, including metal materials such as Al, Au, Ag, Pt, Mo, or piezoelectric polymer materials such as ITO. The materials of the piezoelectric layer 104 mainly include AlN and its alloy materials AlScN, ZnO and its alloy materials ZnVO, PZT, KNN, PVDF and its copolymer materials PVEF-Trfe, etc. The protective layer 106 is used for electrical isolation and physical protection and can be various waterproof polymer materials, such as Parylene, PDMS, polyurethane, etc.

[0042] Furthermore, in some possible implementations, such as Figure 10 As shown, the upper electrode of each sensitive unit component is divided into two parts: an outer electrode 105 - 1 and an inner electrode 105 - 2 , thereby achieving differential reception of acoustic wave signals and improving receiving sensitivity.

[0043] Implementation Method 4: Combination Figures 11 to 13 To illustrate this embodiment, this embodiment shows schematic diagrams of several possible sensitive unit component structures.

[0044] Furthermore, in some possible implementations, the first sensitive unit, the second sensitive unit ... the Nth sensitive unit (N is an integer not less than 2) are any combination of a circle, an ellipse, or a polygon (the number of sides of the polygon is not less than 4). For example, Figure 11 Each sensitive unit of the sensitive unit assembly shown is a circular diaphragm. Figure 12 Each sensitive unit of the sensitive unit assembly shown is an elliptical diaphragm. Figure 13 Each sensitive unit of the sensitive unit assembly shown is a combination of an elliptical diaphragm and a circular diaphragm.

[0045] Implementation Method 5: Combination Figures 14 and 15 In marine science applications, underwater acoustic sensors are one of the core components of marine detection equipment. The bandwidth and sensitivity of the sensor determine the detection resolution and detection distance. The larger the bandwidth, the higher the resolution; the greater the sensitivity, the longer the detection distance.

[0046] Therefore, this embodiment provides an underwater acoustic array sensor, comprising a sensitive unit assembly formed by geometrically interconnecting multiple sensitive units of different sizes, arranged in a specific geometric order. The underwater acoustic array sensor proposed in this embodiment can be used in applications requiring acoustic wave transmission, such as underwater communications, underwater detection and positioning, aquaculture or fish monitoring, and geological exploration. One form of the underwater acoustic array sensor is integration into underwater detection equipment (such as sonar).

[0047] like Figure 14 In the underwater acoustic array sensor, the sensitive unit components are distributed in at least one column, and each column includes at least one sensitive unit component. Specifically, Figure 14 (a) shows that multiple sequentially arranged sensitive unit components are distributed in multiple columns and each two adjacent columns are arranged side by side in the same order; Figure 14 (b) shows that multiple sensitive unit components are arranged in sequence and distributed in multiple columns, and each two adjacent columns are staggered in the same order.

[0048] Furthermore, in some possible implementations, the number of first sensitive units in each piezoelectric sensitive component is the same, the number of second sensitive units is also the same, and the first sensitive units and the second sensitive units in each piezoelectric sensitive component are arranged in the same order.

[0049] Furthermore, in some possible implementations, the piezoelectric sensitive components in every two adjacent columns of the underwater acoustic array sensor are arranged in a staggered manner, which can reduce the acoustic coupling crosstalk between adjacent microsensors and improve the signal-to-noise ratio.

[0050] Furthermore, in some possible implementations, the underwater acoustic array sensor further includes an acoustic impedance matching layer for adjusting the sensitive component ( ) and external media ( ) between the acoustic impedance ( , is the density, The acoustic impedance matching layer has at least one acoustic impedance stack, and the acoustic impedance values ​​and thicknesses of different stacks are different. The acoustic impedance value of the middle stack ( ) can be the arithmetic square root of the acoustic impedance of two adjacent laminates, and the thickness can be ( is a non-zero positive integer, is the wavelength of sound waves propagating within the stack).

[0051] Figure 15 The figure shows the sensitivity curve of a sensor composed of 1×5 sensitive units arranged in a linear array. Figure 13It can be seen from the figure that the array sensor can obtain higher sensitivity and larger working bandwidth due to the increase of working area and the influence of acoustic coupling effect between each sensitive component.

[0052] Implementation Method 6: Combination Figure 16 To illustrate this embodiment, the sensitive unit assembly and its underwater acoustic array sensor provided in the above embodiment can serve as core components in underwater acoustic detection devices and systems. For example, Figure 16 This is a schematic diagram of the structure of an underwater detection device. The device may include a control circuit, a multi-channel signal acquisition circuit, a transmitting transducer, and the underwater acoustic sensor and array described in the above embodiments.

[0053] Optionally, an acoustic impedance matching layer and an acoustic lens structure can be added to the front end of the detection device. The acoustic impedance matching layer is used to match the acoustic impedance difference between the sensor and the medium, improving the efficiency of sound wave transmission; the acoustic lens structure is used to focus the sound waves and increase the signal strength.

[0054] Specifically, using a field programmable gate array (FPGA) as a control chip, signal control and processing can be performed. Through switch control, a pulse generator generates a pulse excitation wave of a certain frequency, which stimulates the transmitting transducer to convert electrical energy into an acoustic wave signal, which is then transmitted to the current area. The transmitted acoustic wave propagates to the target object, where it is reflected. The echo signal is then received by the underwater acoustic sensor. The underwater acoustic sensor and its piezoelectric sensitive component provided in this embodiment converts acoustic energy into an electrical signal through the positive piezoelectric effect. The signal is processed by the acquisition circuit module and transmitted to the control chip for data processing and image generation.

[0055] Among them, the multi-channel signal acquisition circuit module may include a time gain compensation circuit, a low-noise amplifier circuit, a filter circuit, and an analog-to-digital conversion circuit.

[0056] Among them, the transmitting transducer is classified according to its structure and can be at least one of a sandwich type, a cylindrical type, a spherical type, a linear array type or a planar array type transmitting transducer.

[0057] In summary, the present invention provides a piezoelectric sensitive component comprising at least one first sensitive unit and at least one second sensitive unit. The first sensitive unit and the second sensitive unit are geometrically interconnected, and the cross-sectional dimensions of the first sensitive unit are different from those of the second sensitive unit, thereby achieving modal coupling between the units to broaden the receiving bandwidth and improve sensitivity. Multiple sensitive unit components are arranged according to a certain geometric relationship to form an underwater acoustic array sensor. The acoustic coupling effect is utilized to enhance the low-valley sound pressure of the sensitive components through dielectric acoustic coupling, thereby further broadening the bandwidth. The underwater acoustic sensor array can serve underwater detection systems and is of great value in improving target measurement accuracy and detection effectiveness.

[0058] The foregoing description is merely an embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of the claims.

Claims

1. A piezoelectric sensitive component, characterized in that: comprising a substrate (101) and a vibration stack; The vibration stack comprises at least one first sensitive unit (11) and at least one second sensitive unit (12); The first sensitive unit (11) is geometrically interconnected with the second sensitive unit (12) via a geometric interconnection structure (13), forming an integrated sensitive unit component, and is located on the substrate (101); The cross-sectional dimensions or thicknesses of the first sensitive unit (11) and the second sensitive unit (12) are different, and the cross-sectional dimensions are parallel to the substrate (101); The sensitivity curves of the first sensitive unit (11) and the second sensitive unit (12) compensate and couple with each other.

2. A piezoelectric sensitive component according to claim 1, characterized in that: The first sensitive unit (11) and the second sensitive unit (12) each include a structural layer (102), at least one electrode layer, and at least one piezoelectric layer (104); The electrode layer includes an upper electrode (105) and a lower electrode (103); The structural layer (102) serves as a support and carrier for the sensitive unit; When the sound wave is transmitted to the sensitive unit, the sensitive unit is deformed, the piezoelectric layer (104) is polarized, and charges are generated on the surfaces of the upper and lower electrodes respectively, and electrical signals are output through the upper and lower electrodes, and the output electrical signals are used for sensing detection.

3. A piezoelectric sensitive component according to claim 2, characterized in that: The upper electrode (105) includes at least one inner electrode (105-2) and at least one outer electrode (105-1); When receiving sound waves, differential reception is adopted for at least one inner electrode (105-2) and at least one outer electrode (105-1).

4. A piezoelectric sensitive component according to claim 1, characterized in that: The size of the first sensitive unit (11) is larger than the size of the second sensitive unit (12), and the number of the first sensitive units (11) is not more than the number of the second sensitive units (12).

5. The piezoelectric sensitive component according to claim 1, characterized in that: The cross-sectional shapes of the first sensitive unit (11) and the second sensitive unit (12) are circular, elliptical or polygonal, and the number of sides of the polygon is not less than 4; The geometric interconnected structure (13) is rectangular, arc-shaped or broken line-shaped.

6. The piezoelectric sensitive component according to claim 1, characterized in that: At least one first sensitive unit (11) and at least one second sensitive unit (12) are centrally symmetrically distributed in the structural layer (102).

7. The piezoelectric sensitive component according to claim 1, characterized in that: The first sensitive unit (11) has a characteristic size a, the second sensitive unit (12) has a characteristic size b, and a>b; The distance between the center of the first sensitive unit (11) and the center of the second sensitive unit (12) is L, and a / 2 <L<a+b。 8. An underwater acoustic array sensor, characterized in that: The underwater acoustic array sensor includes a piezoelectric sensitive component according to any one of claims 1 to 7, and a plurality of piezoelectric sensitive components are distributed in at least one column.

9. The underwater acoustic array sensor according to claim 8, characterized in that: The number of the first sensitive units (11) and the second sensitive units (12) in each piezoelectric sensitive component is the same, and the first sensitive units (11) and the second sensitive units (12) in each piezoelectric sensitive component are arranged in the same order.

10. The underwater acoustic array sensor according to claim 8, characterized in that: The piezoelectric sensitive components in every two adjacent columns of the underwater acoustic array sensor are arranged in a staggered manner.

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