Ultra-multi-channel PMUT array element two-dimensional array structure and transducer

Abstract

The application provides a super multi-channel PMUT array element two-dimensional arrangement structure and a transducer. The super multi-channel PMUT array element two-dimensional arrangement structure comprises PMUT array elements, integrated amplifiers, a PCB board, a flexible flat cable, a flat cable plug, a backing and a shell. The shell has a bottom plate. The PMUT array elements are uniformly arranged on the PCB board. The PMUT array elements have output wires, and the output wires are connected with electrodes of the PCB board. The back of the PCB board is provided with integrated amplifiers. Each PMUT array element corresponds to an integrated amplifier. The output signals of the integrated amplifiers are connected to the flexible flat cable. The end of the flexible flat cable is connected to the flat cable plug. The flat cable plug passes through the bottom plate and extends to the outside of the bottom plate. The application designs the flexible flat cable and the flat cable plug. Since the signals of multiple array elements are concentrated in the two-dimensional arrangement structure, the connection points of the two-dimensional arrangement structure and external back-end circuits are greatly reduced, the docking difficulty is greatly reduced, and the signal lead-out line problem of multi-channel receiving array elements is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of underwater acoustic transducer, in particular to a two-dimensional arraying and sealing structure of super multi-channel PMUT array elements, and more particularly to a vortex transducer array structure and arraying. BACKGROUND

[0002] Three-dimensional imaging sonar can image underwater stationary or moving targets at high speed and provide multi-angle observation views, and has the characteristics of high image refresh rate, rich feature information, and wide carrier movement tolerance, and thus has wide application prospects in military and civilian fields such as pre-set / mine target identification, underwater vehicle obstacle avoidance, marine engineering implementation, and marine scientific research.

[0003] A planar receiving two-dimensional array (i.e., a two-dimensional arraying structure) is an indispensable structure in three-dimensional imaging sonar technology. The planar receiving two-dimensional array is designed with multi-channel array elements in the horizontal and vertical directions, each array element independently leads out a pair of signal lines, and each signal line is independently connected to an external backend circuit.

[0004] In the planar receiving two-dimensional array, the number of array elements is N*N (N is generally greater than 30), and the horizontal and vertical directions are both set to N. The total number of channels is usually greater than 1000. Therefore, the number of interfaces (i.e., the end interfaces of the signal lines) for connecting to the external backend circuit is also very large. During installation of the planar receiving two-dimensional array, each signal line needs to be connected to the external backend circuit one by one. In summary, the process of connecting the signal lead lines to the backend circuit is complex, which is the main defect of the planar receiving two-dimensional array.

[0005] In addition, in the traditional planar receiving two-dimensional array, the commonly used array element is a piezoelectric ceramic element, but the traditional piezoelectric ceramic element has the defects of large size, heavy weight, and difficult consistency control. SUMMARY

[0006] In view of the defects in the prior art, the purpose of the present application is to provide a two-dimensional arraying structure of super multi-channel PMUT array elements and a transducer.

[0007] The two-dimensional arraying structure of super multi-channel PMUT array elements provided by the present application comprises PMUT array elements, integrated amplifiers, a PCB board, flexible wires, wire plugs, a backing, and a shell. The shell has a bottom plate.

[0008] The PMUT array elements are uniformly arranged on the PCB board, all vibration surfaces are in the same plane, and the arrangement directions of all PMUT array elements are consistent.

[0009] The PMUT array elements have output leads, and the output leads are connected to the electrodes of the PCB board.

[0010] The back of the PCB is provided with an integrated amplifier, each PMUT array element corresponds to an integrated amplifier, and the output signal of the integrated amplifier is connected to the flexible flat cable;

[0011] The lower layer of the PCB is provided with a backing; the backing is mounted on the bottom plate;

[0012] The end of the flexible flat cable is connected to the flat cable plug, the flat cable plug passes through the bottom plate and extends to the outside of the bottom plate.

[0013] Preferably, the PCB is a whole plate;

[0014] Or, it is spliced by multiple plates, and the spacing between each plate is uniform, meeting the requirement of array element half-wavelength arraying.

[0015] Preferably, the vibration surface of the PMUT array element and the inner wall of the shell are water-tight through a sound-transmitting polyurethane material.

[0016] Preferably, the number of PMUT array elements is N*N, and N is greater than or equal to 5.

[0017] Preferably, a heat-conducting layer is further included, the backing (6) is attached with the heat-conducting layer on the side close to the integrated amplifier, for heat dissipation.

[0018] Preferably, the length and width of the backing are consistent with the PCB, and the thickness of the backing is greater than 10 times the wavelength corresponding to the working frequency.

[0019] Preferably, the PCB is a multi-layer plate structure, each layer of plate is provided with PMUT array elements, and each layer of plate is provided with an integrated amplifier on the back; the PMUT array elements on adjacent layers of plates are connected through array element signal transmission lines arranged between the plates, and the integrated amplifiers on each layer of plate are connected to the flexible flat cable through the gap between adjacent plates.

[0020] Preferably, the PMUT array element is made of ALN, ScALN, PZT or ZnO piezoelectric material.

[0021] Preferably, the bottom plate is a metal bottom plate.

[0022] According to the transducer provided by the application, the two-dimensional array structure of the super-multi-channel PMUT array element is adopted.

[0023] The flat cable plug enters the transducer cabin after passing through the backing and the bottom plate, and the part of the flat cable plug entering the cabin has a length, facilitating insertion into the rear-end circuit;

[0024] The flat cable plug is arranged on the inner wall around the cabin.

[0025] Compared with the prior art, the application has the following beneficial effects:

[0026] 1. The soft wire and the wire plug are designed, the signal lines of different PMUT array elements are concentrated to the soft wire through the integrated amplifier circuit, and then connected with the outside through the wire plug; since the concentration of the signal lines of multiple array elements is realized in the two-dimensional array structure (i.e., the planar receiving two-dimensional array), the connection points of the two-dimensional array structure and the outside rear-end circuit are greatly reduced, the docking difficulty is greatly reduced, and the signal lead-out line problem of the multi-channel receiving array element is solved.

[0027] 2. The PMUT array element is used to replace the traditional piezoelectric ceramic array element in the underwater three-dimensional imaging sonar transducer, can solve the problems of complex signal lead-out line and low array element consistency of the traditional two-dimensional receiving transducer array, can greatly reduce the volume and weight of the planar receiving two-dimensional array, reduce the manufacturing cost, and improve the imaging quality. BRIEF DESCRIPTION OF DRAWINGS

[0028] Other features, objects and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments, made with reference to the accompanying drawings:

[0029] Figure 1 is a partial structure diagram of the present application;

[0030] Figure 2 is a layout diagram of the integrated amplifier corresponding to the PMUT array element of the present application;

[0031] Figure 3 is an exploded view structure diagram of the present application;

[0032] Figure 4 is a side view of the present application.

[0033] shown in the figure:

[0034] DETAILED DESCRIPTION

[0035] The present application will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present application, but do not limit the present application in any form. It should be pointed out that, for those skilled in the art, without departing from the concept of the present application, a number of changes and improvements can be made. These all belong to the protection scope of the present application.

[0036] The present application provides a super multi-channel PMUT array element two-dimensional array structure, as shown in Figures 1-4 The present application provides a super multi-channel PMUT array element two-dimensional array structure, as shown in

[0037] The PMUT array elements 1 are uniformly arranged on the PCB board, all the vibration surfaces are in the same plane, and the arrangement directions of all the PMUT array elements are consistent. The spacing between the transverse direction and the longitudinal direction is generally half the wavelength of the working frequency, and the number of array elements in the transverse direction and the longitudinal direction is equal.

[0038] The PMUT array element 1 has two gold-plated thin wires as output wires, which are connected to the electrodes of the PCB board 2. Specifically, the wires are adhered to the electrode pads of the PCB board by dispensing.

[0039] The back of the PCB board 2 is provided with an integrated amplifier 5, and each PMUT array element 1 corresponds to an integrated amplifier 5. The output signal of the integrated amplifier 5 is connected to the flexible flat cable 3. Specifically, the integrated amplifier 5 has two connection points of positive and negative, and the two connection points are connected to the flexible flat cable 3 through a wire. The power lines in the flexible flat cable 3 are arranged at the two edges of the cable, and the outer layer of the flexible flat cable is a shielding layer.

[0040] The lower layer of the PCB board 2 is provided with a backing 6. The backing is made of epoxy resin and oxide powder, and has a certain structural strength. The backing 6 is adhered to the bottom plate 10.

[0041] The end of the flexible flat cable 3 is connected to the flat cable plug 4, and the flat cable plug 4 penetrates through the bottom plate 10 and extends to the outside of the bottom plate 10.

[0042] The PCB board 2 is a whole board, or is spliced by multiple boards. The spacing between each board is uniform, meeting the requirement of half-wavelength arraying of array elements.

[0043] The number of PMUT array elements 1 is N*N, and N is greater than or equal to 5. The super-multiple in the super-multiple channel PMUT two-dimensional array structure refers to a large number of array elements 1, such as N*N, N is greater than or equal to 5. Specifically, the size of a single PMUT array element 1 is 3.5*3.5mm, the spacing between the transverse direction and the longitudinal direction is 5mm, and the number of array elements in the transverse direction and the longitudinal direction is equal, which is 48*48. That is, each of the 48*48 PMUT array elements independently leads out a pair of differential signal lines. After passing through the integrated amplification circuit, the small analog signal of the array element is amplified and output to the end of the flexible flat cable, and enters the rear-end circuit. In a preferred example, as shown in Figure 2 The number of flexible flat cables 3 is 16, because when the number of PMUT array elements is too large, a single flexible flat cable 3 is insufficient to provide wiring for so many PMUT array elements.

[0044] The super-multiple channel PMUT two-dimensional array structure further comprises a heat-conducting layer 8, and the backing 6 is adhered with the heat-conducting layer 8 on the side close to the integrated amplifier 5 for heat dissipation.

[0045] The backer is mixed and configured by materials such as epoxy resin according to the size of the PCB board, specifically, the length and width size of the backer 6 is consistent with the PCB board 2, and the thickness of the backer is greater than 10 times of the wavelength corresponding to the working frequency. In a preferred example, the size of the backer 6 is 300*300*30.

[0046] In a preferred example, the vibration surface of the PMUT array element and the inner wall of the shell 7 are water-tight through the sound-transmitting polyurethane material. That is to say, the two-dimensional array structure of the super multi-channel PMUT array element further comprises a sound-transmitting layer 9 arranged on the shell 7 for sealing and waterproofing of the two-dimensional array structure of the super multi-channel PMUT array element.

[0047] In a preferred example, the PCB board 2 is a multi-layer board structure, preferably a 6-layer board structure. The PMUT array element 1 is arranged on each layer board, and the integrated amplifier 5 is arranged on the back of each layer board. The PMUT array elements 1 on adjacent layer boards are connected through the array element signal transmission line arranged between the boards, and the integrated amplifier 5 on each layer board is connected to the flexible flat cable 3 through the gap between adjacent boards.

[0048] The PMUT array element 1 is a piezoelectric micro-mechanical ultrasonic array element, which has the advantages of small size, easy integration and arrayability. The PMUT array element can generate ultrasonic waves, and the PMUT array element 1 is made of piezoelectric materials such as ALN, ScALN, PZT or ZnO, preferably ScALN piezoelectric material. The bottom plate 10 is a metal bottom plate.

[0049] By replacing the traditional piezoelectric ceramic array element with the PMUT array element, the PMUT array element can be applied to an underwater three-dimensional imaging sonar transducer, which can solve the problems of complex signal lead-out line and low array element consistency of the traditional two-dimensional receiving transducer array, greatly reduce the volume and weight of the planar receiving two-dimensional array, reduce the manufacturing cost, and improve the imaging quality.

[0050] The application also provides a transducer adopting the two-dimensional array structure of the super multi-channel PMUT array element. The cable plug 4 enters the transducer cabin after passing through the backer 6 and the bottom plate 10, and is arranged on the inner wall of the cabin. The cable plug 4 passes through the metal waist-shaped hole, and the part of the cable plug 4 entering the cabin has a certain length, which is convenient for inserting into the rear-end circuit. The waist-shaped hole is water-tight through the sound-transmitting polyurethane material.

[0051] The application designs an integrated amplification circuit, which can minimize the influence of the wire on the analog small signal and reduce the noise of the analog circuit. The application designs a flexible flat cable, which completes the signal lead-out of the receiving array element through the edge lead-out slot (i.e. the slot on the bottom plate 10 for the cable plug 4 to pass through), and has a reasonable structure and is suitable for sonar engineering. The application designs a heat-conducting layer, which aims to dissipate the heat generated by the amplification circuit in time when the receiving array is working, and improve the stability and reliability of the receiving array.

[0052] In summary, the technical scheme can reduce the manufacturing difficulty of the three-dimensional multi-beam image sonar transducer array. The application has simple structure and few process steps. The application has the following advantages compared with the prior art: 1. The connection difficulty of the lead-out line of the two-dimensional array structure in the transducer is greatly reduced; the signal lead-out line difficulty of the multi-channel receiving array element is solved; 2. The high-frequency transceiving transducer array in different working frequency bands can be adapted, and the array element consistency is high; 3. The stability and reliability of the receiving array work are improved. The application optimizes and updates the two-dimensional receiving surface array of the three-dimensional imaging sonar, and reduces the manufacturing difficulty of the three-dimensional image sonar receiving array.

[0053] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0054] The specific embodiments of the application are described above. It should be understood that the application is not limited to the specific implementation described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essential content of the application. The embodiments of the present application and the features in the embodiments can be arbitrarily combined with each other without conflict.

Claims

1. A two-dimensional array structure for ultra-multi-channel PMUT elements, characterized in that, It includes a PMUT array element (1), an integrated amplifier (5), a PCB board (2), a flexible flat cable (3), a flat cable plug (4), a backing (6), and a housing (7); the housing (7) has a base plate (10); The PMUT array elements (1) are evenly arranged on the PCB board, all vibration surfaces are in the same plane, and all PMUT array elements are arranged in the same direction. The PMUT array element (1) has an output wire, which is connected to the electrode of the PCB board (2); An integrated amplifier (5) is set on the back of the PCB board (2). Each PMUT array element (1) corresponds to an integrated amplifier (5). The output signal of the integrated amplifier (5) is connected to the flexible flat cable (3). A backing (6) is provided on the lower layer of the PCB board (2); the backing (6) is mounted on the base plate (10); The end of the flexible flat cable (3) is connected to the flat cable plug (4), which passes through the base plate (10) and extends to the outside of the base plate (10); The vibration surface of the PMUT array element and the inner wall of the outer shell (7) are watertight through sound-permeable polyurethane material; It also includes a thermally conductive layer (8), on the side of the backing (6) facing the integrated amplifier (5), the thermally conductive layer (8) is bonded for heat dissipation; The PCB board (2) is a multi-layer board structure. Each layer board is equipped with a PMUT array element (1), and each layer board has an integrated amplifier (5) on the back. The PMUT array elements (1) on adjacent layers are connected through the array element signal transmission line between the boards, and the integrated amplifier (5) on each layer board is connected to the flexible flat cable (3) through the gap between adjacent boards.

2. The two-dimensional array structure of the ultra-multi-channel PMUT array element according to claim 1, characterized in that, The PCB board (2) is a complete board; Alternatively, it can be composed of multiple panels, with uniform spacing between each panel, meeting the requirements for half-wavelength arraying of array elements.

3. The two-dimensional array structure of the ultra-multi-channel PMUT array element according to claim 1, characterized in that, The number of PMUT array elements (1) is N*N, where N is greater than or equal to 5.

4. The two-dimensional array structure of the ultra-multi-channel PMUT array element according to claim 1, characterized in that, The length and width of the backing (6) are the same as those of the PCB board (2), and the thickness of the backing is more than 10 times the wavelength corresponding to the working frequency.

5. The two-dimensional array structure of ultra-multi-channel PMUT array elements according to claim 1, characterized in that, PMUT array element (1) is an ALN, ScALN, PZT or ZnO piezoelectric material.

6. The two-dimensional array structure of ultra-multi-channel PMUT array elements according to claim 1, characterized in that, The base plate (10) is a metal base plate.

7. A transducer, characterized in that, The array structure of the multi-channel PMUT array element is adopted as described in any one of claims 1 to 6. The ribbon cable plug (4) passes through the backing (6) and the base plate (10) and enters the transducer compartment. The part of the ribbon cable plug (4) that enters the compartment has a length to facilitate insertion into the rear circuit. The cable plugs (4) are arranged on the inner walls around the cabin.

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