Acoustic transducer array assembly

Abstract

The present disclosure relates to an acoustic transducer array assembly configured to provide acoustic pressure waves to at least one sample location including a printed circuit board having at least one plated through hole and a matching layer including an acoustic medium configured to provide an acoustic impedance match between an acoustic impedance of at least one piezoelectric element and a target sample. The acoustic transducer array assembly further includes at least one acoustic transducer having at least one signal electrode electrically connected to the at least one plated through hole and acoustically coupled to the matching layer; at least one ground electrode electrically connected to the at least one plated through hole and acoustically coupled to the matching layer; and the at least one piezoelectric element being electrically connected to the at least one signal electrode and the at least one ground electrode, wherein the at least one piezoelectric element is configured to produce the acoustic pressure waves when an electric voltage is applied between the at least one signal electrode and the at least one ground electrode to the piezoelectric element.

Description

ACOUSTIC TRANSDUCER ARRAY ASSEMBLYCROSS-REFERENCE TO RELATED APPLICATION(S)

[0001] This application is being filed on May 10, 2024 as a PCT International application and claims the benefit of and priority7to U.S. Provisional Patent Application No. 63 / 501,988 filed on May 12, 2023. the disclosure of which is hereby incorporated by reference in its entirety.BACKGROUND

[0002] Acoustic transduction can be used to convert electrical energy into sound waves that are suitable for measuring small volumes of liquid. In certain examples, piezoelectric elements, having electrodes on each side, can be attached to a printed circuit board (PCB) such that they are in electrical contact with circuits such as traces or pads on the PCB. The electrical contact between the PCB circuit and the piezoelectric electrodes may be facilitated by placing a conductive material between each piezoelectric electrode and a PCB circuit. When a voltage is applied across each of the piezoelectric electrodes, the piezoelectric element expands or contracts, which produces acoustic pressure waves that transmit through solids and liquids, including reflected waves returning to the piezo element.SUMMARY

[0003] The present disclosure relates to an acoustic transducer. Specifically, the present disclosure relates to an acoustic transducer including one or more piezoelectric elements that are in acoustic contact with the bottom of one or more containers with liquid sample. In certain applications, the one or more piezoelectric elements are arranged to accommodate samples that are organized in an array, such as a rectilinear array. In certain applications, the acoustic energy7can be used to measure the sample from a container. In certain applications, the acoustic transducer array assembly is configured to apply acoustic pressure waves to a plurality7of samples in succession from a plurality of acoustic transducers.

[0004] In one example, an acoustic transducer array assembly is configured to provide acoustic pressure waves to at least one sample location including a printed circuit board having at least one plated through hole and a matching layer including an acousticmedium configured to provide an acoustic impedance match between an acoustic impedance of at least one piezoelectric element and a target sample. The acoustic transducer array assembly further includes at least one acoustic transducer having at least one signal electrode electrically connected to the at least one plated through hole and acoustically coupled to the matching layer; at least one ground electrode electrically connected to the at least one plated through hole and acoustically coupled to the matching layer; and the at least one piezoelectric element being electrically connected to the at least one signal electrode and the at least one ground electrode, wherein the at least one piezoelectric element is configured to produce the acoustic pressure waves when an electric voltage is applied between the at least one signal electrode and the at least one ground electrode to the piezoelectric element.

[0005] In another example, a method for providing acoustic pressure waves to at least one location includes providing an acoustic transducer array assembly, wherein the acoustic transducer array assembly includes: at least one printed circuit board including at least one plated through hole and at least one matching layer including an acoustic medium configured to provide an acoustic impedance match between at least one piezoelectric element and at least one target sample; and at least one acoustic transducer including at least one signal electrode electrically connected to the at least one plated through hole and acoustically connected to the at least one matching layer, at least one ground electrode electrically connected to the at least one plated through hole and acoustically connected to the at least one matching layer, and at least one piezoelectric element electrically connected to the at least one signal electrode and the at least one ground electrode. The method further includes applying an electric voltage between the at least one signal electrode and the at least one ground electrode to the at least one piezoelectric element; converting the electric voltage into the acoustic pressure waves; and projecting the acoustic pressure waves to the at least one location, wherein at least one signal reflection of the acoustic pressure waves is minimized due to the acoustic impedance match.

[0006] In yet another example, a method of making an acoustic transducer array assembly, the method includes providing the acoustic transducer array assembly, wherein the acoustic transducer array assembly includes a printed circuit board including at least one plated through hole and at least one matching layer configured to provide an acoustic impedance match between at least one piezoelectric element and at least one targetsample. The method further includes electrically connecting at least one signal electrode to the acoustic transducer array assembly and acoustically connecting the at least one signal electrode to the at least one matching layer; electrically connecting at least one ground electrode to the acoustic transducer array assembly and acoustically connecting the at least one ground electrode to the at least one matching layer; and electrically connecting the at least one piezoelectric element to the at least one signal electrode and the at least one ground electrode.

[0007] A variety of additional aspects will be set forth in the description that follows. The aspects can relate to individual features and to combinations of features. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory’ only and are not restrictive of the broad inventive concepts upon which the examples disclosed herein are based.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The following drawings are illustrative of examples of the present disclosure and therefore do not limit the scope of the present disclosure. Examples of the present disclosure will hereinafter be described in conjunction with the appended drawings, wherein like numerals denote like elements.

[0009] FIG. 1 shows a block diagram of an acoustic transducer array assembly, including a PCB and at least one acoustic transducer.

[0010] FIG. 2 show s a perspective view of the acoustic transducer and the acoustic transducer array assembly of FIG. 1, wherein the acoustic transducer array assembly includes a plurality of acoustic transducers.

[0011] FIG. 3 shows a top isometric view of the acoustic transducer of FIG. 1.

[0012] FIG. 4 shows a bottom isometric view of the acoustic transducer of FIG. 1.

[0013] FIG. 5 show s a cross-sectional view' of the acoustic transducer of FIG. 3.

[0014] FIG. 6 shows an exploded view of the acoustic transducer array assembly ofFIG. 1. wherein the piezoelectric elements include piezoelectric discs positioned at each through hole.

[0015] FIG. 7 shows a side exploded view of the acoustic transducer array assembly of FIG. 6.

[0016] FIG. 8 shows a cross-sectional view- of the acoustic transducer array assembly of FIGS. 6-7.

[0017] FIG. 9 shows a cross-sectional view of the acoustic transducer array assembly of FIGS. 6-8, including a matching layer integrated into the PCB.

[0018] FIG. 10 shows an exploded view of another embodiment of the acoustic transducer array assembly of FIG. 1, wherein the piezoelectric elements include a piezoelectric plate.

[0019] FIG. 11 shows a side exploded view of the acoustic transducer array assembly of FIG. 10.

[0020] FIG. 12 shows an exploded view of another embodiment of the acoustic transducer array of FIG. 1, wherein the acoustic transducer array includes at least one high density connector, and the piezoelectric elements include piezoelectric discs positioned at each plated through hole.

[0021] FIG. 13 shows a side exploded view of the acoustic transducer array assembly of FIG. 12.

[0022] FIG. 14 shows a cross-sectional view7of the acoustic transducer arrayassembly of FIG. 12.

[0023] FIG. 15 shows an exploded view of another embodiment of the acoustic transducer array of FIG. 12, wherein the acoustic transducer array includes a matching layer and a lens.

[0024] FIG. 16 shows a side exploded view of the acoustic transducer array assembly of FIG. 15.

[0025] FIG. 17 shows a cross-sectional view of the acoustic transducer array assembly of FIG. 15.

[0026] FIG. 18 shows an example side view of the acoustic transducer, wherein various signal connections are arranged in a parallel connection.

[0027] FIG. 19 shows an example side view of the acoustic transducer, wherein various signal connections are arranged in a series connection.

[0028] FIG. 20 show s a bottom view7of a PCB or flexible circuit illustrating the first layer of the PCB or flexible circuit having a plurality of column multiplexing traces.

[0029] FIG. 21 shows a top view of a PCB or flexible circuit illustrating the first layer of the PCB or flexible circuit having a plurality of row multiplexing traces.

[0030] FIG. 22 show s a flow diagram of a method for providing acoustic vibrations to at least one sample-testing location.

[0031] FIG. 23 shows a schematic illustration of an electronic system for operating the acoustic transducer array assembly.

[0032] In the appended figures, similar components and / or features can have the same reference label.DETAILED DESCRIPTION

[0033] Various examples will be described in detail with reference to the drawings, wherein like reference numerals represent like parts and assemblies throughout the several views.

[0034] In general terms, the present disclosure is directed to an acoustic transducer array assembly configured to provide acoustic pressure waves to various lab materials. In certain examples, the acoustic transducer array assembly provides acoustic-driven pressure waves through solid and liquid materials. In some embodiments, and by nonlimiting example, the acoustic transducer array assembly is configured to provide acoustic pressure waves to at least one sample-testing location.

[0035] Although the term “printed circuit board’7(PCB) is sometimes used to refer to a flat, rigid board including one or more non-conductive substrate materials, such as fiberglass or plastic, it is not intended to be so limited in the present disclosure. For example, in some embodiments the PCB is or includes a flex circuit (also known as flexible electronics). The PCB can include a variety of possible non-conductive substrate materials that are used to mechanically support components within a transducer array assembly, as well as electrically conductive materials (such as electrical traces, conductive pads, ground planes, etc.) to electrically connect electronic components. Specifically, examples of printed circuit boards include rigid printed circuit boards (often including fiberglass or plastic) or flexible circuits (including a flexible substrate such as polyimide or a conductive polyester film). Accordingly, the PCB described herein can include rigid circuit boards, flexible circuit boards, or combinations thereof.

[0036] Furthermore, the present disclosure is directed to an acoustic transducer array assembly that is configured to provide a plurality of acoustic transducers that function together to increase the efficiency and lower the cost of automated manufacturing processes.

[0037] FIG. 1 shows a block diagram of an acoustic transducer array assembly 100, including a PCB 102 and at least one acoustic transducer 108.

[0038] The PCB 102 is used to electrically connect and organize electronic components. The PCB 102 has a plurality of conductive pads 105 (as illustrated and described in further detail with respect to FIGS. 18-19) that are configured to electrically connect to other electronic components through a conductive connection, such as a soldered connection. In some embodiments, the PCB 102 is a flexible circuit including a flexible substrate such as polyimide or a conductive polyester film. The flexible circuit is configured to electrically connect to. and mechanically couple to. a plurality of electronic devices. In certain examples, the flexible circuit may be manufactured using similar components that are included within a rigid PCB 102. In certain examples, it is desirable to include a flexible circuit because the flexible substrate includes acoustic impedance properties that provide an impedance match between an acoustic impedance of at least one piezoelectric element 114 and a target sample. In certain examples, the flexible circuit includes a matching layer 106 that is integrated into the flexible circuit.

[0039] The PCB 102 includes at least one plated through hole 104, which is an electrical connection between copper layers in the PCB 102. The plated through hole 104 can be created by drilling a hole through two or more adjacent layers of the PCB 102. In some embodiments, the plated through hole 104 includes a copper plating that electrically connects elements of the PCB 102 to component leads that are received at the plated through hole 104. In some embodiments, the PCB 102 includes a plurality of plated through holes 104. In some embodiments, the PCB 102 includes a plurality of plated through holes 104 that are arranged in a rectilinear array. In some embodiments, the PCB 102 includes a plurality7of plated through holes 104 within a range between 1 to 384 plated through holes 104. In some embodiments, the PCB 102 includes a plurality of plated through holes 104 arranged in a one-dimensional array. In some embodiments, the PCB 102 includes ninety-six plated through holes 104 arranged in an 8x12 two- dimensional rectilinear array with nine-millimeter center-to-center spacing. In some embodiments, the PCB 102 includes 384 plated through holes 104 arranged in a 16x24 rectilinear array. In some embodiments, the PCB 102 includes 384 plated through holes 104 arranged in a symmetrical, rectilinear array with four-and-a-half-millimeter center- to-center spacing. In some embodiments, a pitch between each plated through hole 104 is within a range from 4.5 millimeters to 36 millimeters. In certain embodiments, the PCB includes greater than 384 plated through holes.

[0040] Furthermore, the PCB 102 includes at least one matching layer 106 including an acoustic medium configured to provide an acoustic impedance match between an acoustic impedance of at least one piezoelectric element 114 and a target sample. In certain examples, the matching layer 106 provides an acoustic impedance match to layers that are adjacent to the matching layer 106. In certain examples, the matching layer 106 provides an acoustic impedance match between the piezoelectric element 114 and the lens 302. which is illustrated and described in further detail with respect to FIGS. 3-8. In some embodiments, the acoustic medium includes a polymeric material. In some embodiments, the polymeric material includes at least one of polyimide, polyester, polystyrene, poly vinylidene fluoride (PDVF), aluminum, glass, polyphenylene oxide, or polypropylene. Impedance matching is desirable to maximize power transfer while minimizing signal reflections that create destructive interference. The PCB 102, plated through holes 104, and the at least one matching layer are further discussed infra with reference to FIGS. 6-14.

[0041] The at least one acoustic transducer 108 is configured to electrically connect to, and acoustically couple to, the PCB 102 to produce acoustic pressure waves. In certain examples, the input voltage signal includes a frequency range between 1 MHz to 20 MHz. In some embodiments, the at least one acoustic transducer 108 is acoustically coupled to the PCB 102 and electrically connected to the PCB 102 at each plated through hole 104. In some embodiments, the acoustic transducer 108 is electrically connected to the PCB 102 using a soldered connection or a conductive epoxy. In some embodiments, the acoustic transducer 108 is coaxially aligned with the plated through hole 104 to provide two-dimensional alignment of its components. The acoustic transducer 108 includes at least one signal electrode 110, at least one ground electrode, at least one electrical connection 112, and at least one piezoelectric element 114.

[0042] The at least one signal electrode 110 is configured to produce a signal output within the acoustic transducer array assembly 100. The at least one signal electrode 110 is electrically connected to at least one ground electrode 111. A voltage potential is present between the at least one signal electrode and the at least one ground electrode that allows a voltage to be applied to components between the signal electrode 110 and the ground electrode 111, such as a piezoelectric element 114, which is described below . In certain examples, the at least one ground electrode includes an electrical ground used in radio frequency systems C’RF ground’"). It is desirable to establish an electrical ground,such as the RF ground, to provide a voltage from the signal electrode 110 to the ground electrode 111 across the at least one piezoelectric element 114 (discussed infra). In certain examples, it is desirable to establish a good electrical connection between the signal electrode 110 and the ground electrode 111 to reduce electromagnetic interference and improve the efficiency and performance of the acoustic transducer array assembly 100.

[0043] In some embodiments, the at least one acoustic transducer 108 includes at least one electrical connection 112. In certain examples, the at least one electrical connection 112 provides an electrical connection between the ground electrode 111 and the second layer of the PCB 102B. In certain examples, the at least one electrical connection 112 provides an electrical connection between the signal electrode 110 and the first layer of the PCB 102A. In certain examples, the electrical connection 112 includes either an electrically conductive bond or a non-conductive bond between the ground electrode 111 and the second layer of the PCB 102B. In certain examples, the electrical connection 112 includes either an electrically conductive bond or a non- conductive bond between the signal electrode 110 and the first layer of the PCB 102A.

[0044] In certain examples, the conductive bond includes a soldered connection. In certain examples, the conductive bond includes a conductive epoxy, such as a silver- loaded epoxy, positioned within the plated through hole 104 that electrically connects the at least one signal electrode 110 to the first layer of the PCB 102A and the at least one ground electrode 1 1 1 to the at second layer of the PCB 102B.

[0045] In certain examples, the non-conductive bond includes a capacitive connection that includes an electric voltage potential between the signal electrode 110 and the ground electrode 111. In certain examples, the non-conductive bond includes a connection between the piezoelectric element 1 14 and the ground electrode 111 using a metal material, such as aluminum. In certain examples, the metal material contacts the piezoelectric element 114 to facilitate the transfer of an electric voltage from the electric field to the piezoelectric element 114. In certain examples, the metal material includes an aluminum sheet.

[0046] In certain examples, the acoustic transducer array assembly includes a signal electrode 110 that is positioned between each plated through hole 104 on the PCB 102. In certain examples, at least one connector 1101 is provided on the acoustic transducer array assembly that provides an electrical voltage to each acoustic transducer 108 throughPCB traces. The at least one connector 1101 is illustrated and described in further detail with respect to FIGS. 12-17.

[0047] The at least one piezoelectric element 114 is configured to produce acoustic pressure w aves through a process called the inverse piezoelectric effect, where electrical energy is converted to mechanical energy in the form of an acoustic wave. The piezoelectric element 114 performs this function by receiving an electric voltage and releasing energy in the form of acoustic pressure waves.

[0048] In some embodiments, the at least one piezoelectric element 1 14 includes a piezoelectric plate spanning across one or more plated through holes 104. In certain applications, having a single piezoelectric plate may be desirable because it increases manufacturing efficiency to create a piezoelectric element 114 for multiple acoustic transducers 108 while reducing costs of production. A piezoelectric element including a piezoelectric plate is described and illustrated in further detail with respect to FIGS. 10- 12.

[0049] In some embodiments, the at least one piezoelectric element 114 includes at least one piezoelectric disc positioned at each plated through hole 104. Including an individual piezoelectric disc within each acoustic transducer 108 may be desirable because it decouples the piezoelectric elements 114 of each acoustic transducer 108 from one another when multiple acoustic transducers 108 are included on a single acoustic transducer array assembly 100 and allows the piezoelectric discs to expand or contract freely. A piezoelectric element 1 14 including at least one piezoelectric disc is described and illustrated in further detail with respect to FIGS. 6-9.

[0050] In some embodiments, the at least one acoustic transducer array assembly 100 is arranged in an orientation as shown in this Figure with components stacked on top of one another. In certain examples, two layers of the PCB 102 A, 102B include an integrated matching layer 106 as part of a flexible circuit and a plated through hole 104. The two layers of the PCB 102A, 102B are electrically connected to the acoustic transducer 108 via an electrical connection 112 as described above. Furthermore, the acoustic transducer 108 includes a signal electrode 110 that is electrically connected to the first layer of the PCB 102A and a ground electrode 111 that is electrically connected to the second layer of the PCB 102B. A voltage potential exists between the signal electrode 110 and the ground electrode 111 to allow- an electric voltage to be transferred to the piezoelectric element.

[0051] The acoustic transducer 108, the at least one signal electrode 110, the at least one ground electrode 111, the at least one electrical connection 112, and the at least one piezoelectric element 114 are further discussed infra with reference to FIGS. 3-5.

[0052] FIG. 2 shows a perspective view of the acoustic transducer 108 and the acoustic transducer array assembly 100 of FIG. 1, wherein the acoustic transducer array assembly 100 includes a plurality of acoustic transducers 108.

[0053] It is desirable to (1) provide acoustic pressure waves to a plurality of sample sites, (2) provide an electrical connection to each acoustic transducer 108 on an acoustic transducer array assembly that is easily accessible, and (3) maximize the power transfer of acoustic pressure waves while minimizing unintended signal reflections that create destructive interference. This Figure illustrates the placement of a plurality of acoustic transducers 108 arranged in an 8x12 rectilinear array within an acoustic transducer array assembly 100. The rectilinear array of acoustic transducers provides acoustic pressure waves to a plurality of sample sites while being readily incorporated into existing labware that utilizes similar rectilinear array patterns. Furthermore, each plated through hole 104 positioned on the PCB 102 provides an accessible connection between the acoustic transducer 108 and the PCB 102. Further yet, the matching layer 106 is configured to provide an acoustic impedance match between an acoustic impedance of at least one piezoelectric element 114 and a target sample.

[0054] FIG. 3 shows a top isometric view of the acoustic transducer 108 of FIG. 1.

[0055] In this Figure, the acoustic transducer 108 includes the PCB 102, the plated through hole 104, and the piezoelectric element 114. In this embodiment, the piezoelectric element 114 is a piezoelectric disc that is configured to receive an electric voltage through a voltage potential between the signal electrode 110 and the ground electrode 111. The PCB 102 includes a first layer 102A and a second layer 102B. In certain examples, the first layer 102A is configured to receive a voltage from the signal electrode 110 and transfer the voltage to the piezoelectric element 114 through the electric connection 112. The second layer 102B is configured to ground the acoustic transducer 108. In certain examples, the acoustic transducer 108 includes a single acoustic transducer 108.

[0056] The acoustic transducer 108 further includes discrete components, an acoustic lens 302. an acoustic transducer matching layer 304. and a piezo backing material 306. The acoustic lens 302 is configured to focus the acoustic waves to target adesired location with a desired frequency and amplitude. In some embodiments, the acoustic transducer matching layer 304 can be provided in conjunction with the matching layer 106 to further adjust the acoustic impedance of the acoustic transducer array assembly 100. The piezo backing material 306 is configured to absorb the acoustic energy, reduce reflections of acoustic pressure waves returning to the piezoelectric element 114, and focus the acoustic waves that are transmitted on a front side of the piezoelectric element. In some embodiments, assembly of the various components of the acoustic transducer 108 is achieved by connecting the layers with a liquid epoxy layer that is cured solid. In certain examples, the piezo backing material 306 includes at least one of tungsten powder and epoxy, conductive epoxy, and other polymers.

[0057] Additionally, this Figure includes the signal electrode 110 positioned on a top side of the piezoelectric element 114. Electrical connections between the signal electrode 110 and the first layer of the PCB 102A are illustrated and described in further detail with respect to FIG. 1. Electrical connections between the ground electrode 111 and the second layer of the PCB 102B are illustrated and described in further detail with respect to FIG. 1.

[0058] FIG. 4 shows a bottom isometric view of the acoustic transducer 108 of FIG. 1.

[0059] This Figure includes similar components discussed in FIG. 3. Additionally, this Figure includes the ground electrode 11 1 positioned on a bottom side of the piezoelectric element 1 14. Electrical connections between the signal electrode 1 10 and the first layer of the PCB 102A are illustrated and described in further detail with respect to FIG. 1. Electrical connections between the ground electrode 111 and the second layer of the PCB 102B are illustrated and described in further detail with respect to FIG. 1.

[0060] FIG. 5 shows a cross-sectional view of the acoustic transducer 108 of FIG. 3.

[0061] This Figure includes many of the same components of FIG. 3. The acoustic transducer 108 is positioned at a plated through hole 104 of the PCB 102. The acoustic lens 302 is positioned on a front side of the acoustic transducer 108. The piezoelectric element 114 is positioned between two segments of the PCB 102, including a first layer 102A and a second layer 102B. The acoustic transducer matching layer 304 is positioned between the acoustic lens 302 and the piezoelectric element 114 on a front side of the piezoelectric element 114 and the piezo backing material 306 is positioned on a back sideof the piezoelectric element 114. In this configuration, the plated through hole 104 is also used to position components coaxially with the piezoelectric element 114, and to provide a receptacle to receive piezo backing materials 306 until it is cured hard.

[0062] FIG. 6 shows an exploded view of the acoustic transducer array assembly of FIG. 1, wherein the piezoelectric elements 114 include piezoelectric discs positioned at each plated through hole 104.

[0063] The plated through holes 104, PCB 102, and the discrete components (including the acoustic lens 302, acoustic transducer matching layer 304, and the piezoelectric element 114), are similar to components discussed above. The acoustic transducer array assembly 100 includes an acoustic transducer array assembly frame 502 and an acoustic transducer array assembly bracket 508 for securing components within the acoustic transducer array assembly 100 and mounting the acoustic transducer array assembly 100 to other devices within an assembly.

[0064] In this Figure, the acoustic transducer array assembly 100 includes a plurality of signal electrodes 110 that electrically connect to the PCB 102A. In some embodiments, the signal electrodes 110 are electrically connected to the PCB 102 A using a direct connection, such as a soldered connection. In some embodiments, the signal electrodes 110 electrically connect to the PCB 102A using direct-connect cables that press fit directly into the PCB 102.

[0065] Furthermore, the acoustic transducer array assembly 100 includes an electrical connection 1 12 that is configured to provide an electric voltage to the piezoelectric element 114. As shown in the figure, and in some embodiments, the electrical connection 112 can include a direct connection, such as a plurality of conductor rings 308 configured to electrically connect to the PCB 102 at a perimeter of each plated through hole 104. The piezoelectric element 114 expands and contracts to produce acoustic w aves as electric voltage is applied across the piezoelectric element 114 from the electrical connection 112. The acoustic waves are focused on a desired target using the acoustic lens 302 as described and illustrated in FIGS. 3-5. Furthermore, each acoustic transducer 108 can include an acoustic transducer matching layer 304 for providing an acoustic impedance match betw een an acoustic impedance of at least one piezoelectric element 114 and a target sample. Each element of the acoustic transducer is secured at a front side of the acoustic transducer array assembly by a top layer of the PCB 102 and the acoustic transducer array assembly frame 502.

[0066] FIG. 7 shows a side exploded view of the acoustic transducer array assembly 100 of FIG. 6. This Figure includes the same components of FIG. 6 and illustrates the layering of each component of the acoustic transducer array assembly 100 from a side view. In some embodiments, assembly of the various components of the acoustic transducer 108 is achieved by connecting the layers with a liquid epoxy layer that is cured solid.

[0067] FIG. 8 shows a cross-sectional view of the acoustic transducer array assembly 100 of FIGS. 6-7. The cross-sectional view includes an acoustic transducer 108 centered within the Figure. The acoustic transducer 108 includes many of the same components discussed supra. In some embodiments, the piezoelectric element 114 receives an electrical voltage between the signal electrode 110, which is electrically connected to the first layer of the PCB 102A, and the ground electrode 111, which is electrically connected to the second layer of the PCB 102B. The electrical voltage passes through the conductor ring 308, past the piezo backing material 306, to the piezoelectric element 114 (shown here as a piezoelectric disc). The piezoelectric element 114 then expands and / or contracts as electrical voltage is received. The expansion / contraction of the piezoelectric element 114 generates an acoustic pressure wave that travels through the acoustic transducer matching layer 304 to match the impedance of the piezoelectric element 114 with a target sample. The acoustic pressure wave is then focused by the acoustic lens 302 toward a desired target. Additional acoustic pressure waves traveling in the opposite direction from a back side of the piezoelectric element 1 14 are absorbed by the piezo backing material 306.

[0068] FIG. 9 shows a cross-sectional view of the acoustic transducer array assembly 100 of FIGS. 6-8, including a matching layer 106 integrated into the PCB 102. In some embodiments, it is desirable to include a matching layer 106 that is integrated into the PCB 102 to maximize the power transfer of acoustic pressure waves while minimizing signal reflections. Furthermore, an integrated matching layer 106 provides desirable impedance-matching properties without the need to provide an additional impedance-matching layer. In some embodiments, the integrated matching layer 106 includes at least one of polyimide or polyester. In some embodiments, the matching layer 106 is integrated into a second layer of the PCB 102B that serves as a grounding layer. In some embodiments, the piezoelectric element 114 is positioned below the PCB 102 and the integrated matching layer 106.

[0069] FIG. 10 shows an exploded view of another embodiment of the acoustic transducer array assembly 100 of FIG. 1, wherein the piezoelectric elements 114 include a piezoelectric plate, and a flex circuit. In certain examples, the flex circuit may replace the PCB 102.

[0070] This Figure includes many of the same elements of the acoustic transducer array assembly 100 discussed in FIGS. 1-9, including the acoustic transducer array assembly bracket 508, the signal electrodes 110, a first layer of the PCB 102A, the conductor rings 308, the plated through hole 104, the piezo backing layers 306, and a second layer of the PCB 102B, in the form of a flex circuit, that serves as a grounding layer for electric voltage field across the piezoelectric element 114.

[0071] Furthermore, this Figure includes the at least one piezoelectric element 114, which is shown as a piezoelectric plate. The piezoelectric plate is supported by a non- conductive alumina or epoxy backing material 902 that is also in contact with the conductor rings 308. The alumina or epoxy backing material 902 is placed between the conductor rings 308, which are filled with a conductive backing material 306, to prevent shorting of the voltage field between signal electrodes 110. In certain examples, the conductive backing material includes tungsten metal or a conductive epoxy. Furthermore, the piezoelectric plate is secured on a front side of the piezoelectric plate with the acoustic transducer array assembly frame 502. The acoustic transducer array assembly frame 502 electrically connects to a second layer of the PCB 102B in the format of a flex circuit, that serves as a grounding layer. In some embodiments, the matching layer 106 is positioned on top of the second layer of the PCB 102B to provide an acoustic impedance match to a target sample for acoustic pressure waves that are created by the expansion and contraction of the piezoelectric plate.

[0072] FIG. 11 shows a side exploded view of the acoustic transducer array assembly of FIG. 10. This Figure includes similar components described above. In some embodiments, assembly of the various components of the acoustic transducer array assembly 100 is achieved by connecting the layers with liquid epoxy that is cured solid.

[0073] FIG. 12 shows an exploded view of another embodiment of the acoustic transducer array 100 of FIG. 1, wherein the acoustic transducer array 100 includes at least one connector 1101 and the piezoelectric elements 114 include piezoelectric discs positioned at each plated through hole 104.

[0074] In this Figure, the acoustic transducer array 100 includes many of the same components of FIGS. 6-8, including the second layer 102B of the PCB 102 in the format of a flex circuit that serves as a grounding layer, the acoustic transducer array assembly frame 502, the piezoelectric element 114, the second layer of the 102A of the PCB 102 that serves as signal connection layer, and a discrete piezo backing layer 306.

[0075] Additionally, in this Figure, the acoustic transducer array 100 includes at least one connector 1101. In certain examples, the connector 1101 includes electrical connector pins for electrically connecting to the PCB 102 at the second layer 102B with a first end 1107. The electrical connector pins provide an electrical voltage to the second layer 102B that electrically connect various components to the second layer 102B through PCB traces. In certain examples, the at least one connector 1101 includes 64 electrical connector pins to connect piezo electric elements 114 and signal electrodes 110 to multiplexing electronics (not shown). In certain examples, the at least one connector 1101 includes two connectors 1101 positioned on opposite ends of the second layer 102B. In certain examples, the connector 1101 includes a receptacle 1103.

[0076] Additionally, in this Figure, the acoustic transducer array 100 includes a spacer 1105 for providing a gap between the first layer 102A and the second layer 102B. In certain examples, the spacer 1105 allows the piezoelectric element 114 to be placed in a precise lateral positioning of the piezoelectric element 114 within the plated through holes 104 of the PCB 102. In certain examples, the spacer 1105 includes a thickness that is substantially the same as the piezoelectric element 114.

[0077] FIG. 13 a side exploded view of the acoustic transducer array assembly of FIG. 12. This Figure includes similar components described above. In some embodiments, assembly of the various components of the acoustic transducer array assembly 100 is achieved by connecting the layers with liquid epoxy that is cured solid.

[0078] FIG. 14 shows a cross-sectional view of the acoustic transducer array assembly of FIG. 12. This Figure includes similar components described above, including the piezoelectric element 114, the piezo backing material 306, the first layer 102A of the PCB 102 that serves as a signal-conducting layer, the second layer 102B of the PCB 102 that serves as a grounding layer, and the spacer 1105.

[0079] FIG. 15 shows an exploded view of another embodiment of the acoustic transducer array assembly 100 of FIG. 12, wherein the acoustic transducer array assembly 100 includes an acoustic transducer discrete matching layer 304 and a lens 302.

[0080] FIG. 16 shows a side exploded view of the acoustic transducer array assembly of FIG. 15. This Figure includes similar components described above. In some embodiments, assembly of the various components of the acoustic transducer array assembly 100 is achieved by connecting the layers with liquid epoxy that is cured solid.

[0081] FIG. 17 shows a cross-sectional view of the acoustic transducer array assembly of FIG. 15. This Figure includes similar components described above, including the piezoelectric element 114, the piezo backing material 306, the first layer 102A of the PCB 102 that serves as a signal -conducting layer, the second layer 102B of the PCB that serves as a grounding layer, the spacer 1105, the lens 302, and the acoustic transducer matching layer 304, and the spacer 1105 to provide precise lateral positioning of the piezoelectric discs with the plated through holes 104 of the PCB 102A, 102B.

[0082] FIG. 18 shows a block diagram of the acoustic transducer 108, wherein various acoustic connections are arranged in a parallel connection.

[0083] In this Figure, the acoustic transducer 108 includes similar components discussed above. Acoustic components within the acoustic transducer 108 are arranged in a parallel connection where an acoustic pressure wave produced by the piezoelectric element 114 can pass through an integrated layer that includes the signal connection at the plated through hole 104 and either the piezo backing material 306 or the acoustic matching material 304. The signal electrode 110 and the ground electrode 111 are electrically connected to the PCB 102 at the first layer 102A and the second layer 102B, respectively. The first layer 102A and the second layer 102B include an annular ring that surrounds the acoustic matching layer 304 and the piezo backing layer 306, respectively. Furthermore, the acoustic transducer 108 includes a signal electrode 110 and a ground electrode 111 electrically connected to opposing ends of the piezoelectric element 114. Further yet, the first layer 102A includes the piezo backing layer 306 and the second layer 102B includes the acoustic matching layer 304.

[0084] FIG. 19 shows a block diagram of the acoustic transducer 108, wherein various acoustic connections are arranged in a series connection.

[0085] In this Figure, the acoustic transducer assembly 100 includes similar components discussed above. Acoustic components within the acoustic transducer 108 are arranged in a series connection where an acoustic pressure wave produced by the piezoelectric element 114 can pass through multiple layers that include the signal connection at the conductive pad 105 on the PCB 102 and either the piezo backingmaterial 306 or the acoustic matching material 304. The signal electrode 110 and the ground electrode 111 are electrically connected to the PCB 102 at the first layer 102 A and the second layer 102B, respectively, at the conductive pad 105 on the PCB 102.

[0086] FIG. 20 shows a bottom view of a PCB 102 or flex circuit illustrating the first layer of the PCB 102A or flex circuit having a plurality of column multiplexing traces 1200.

[0087] The column multiplexing traces 1200 provide an electrical connection between acoustic transducers 108 that are positioned within a single column on the transducer array assembly 100. In certain examples, the column multiplexing traces 1200 provide an electric voltage to one acoustic transducer 108 at a time. In certain examples, the column multiplexing traces 1200 provide an electric voltage to acoustic transducers in succession along the column multiplexing trace 1200. In certain examples, it may be desirable to energize a single acoustic transducer 108 within the column multiplexing trace 1200 without energizing a neighboring acoustic transducer to prevent receiving destructive interference of acoustic pressure waves from neighboring acoustic transducers 108.

[0088] In certain examples, the transducer array assembly 100 includes eight or twelve column multiplexing traces 1200 configured to provide electrical connections within an acoustic transducer array assembly having an 8x12 arrangement of acoustic transducers 108. In certain examples, the transducer array assembly 100 includes sixteen or twenty-four column multiplexing traces 1200 configured to provide electrical connections within an acoustic transducer array assembly having an 16x24 arrangement of acoustic transducers 108.

[0089] FIG. 21 shows a bottom view of a PCB 102 or flex circuit illustrating the first layer of the PCB 102A or flex circuit having a plurality of row multiplexing traces 1202.

[0090] The row multiplexing traces 1202 provide an electrical connection between acoustic transducers 108 that are positioned within a single row on the transducer array assembly 100. In certain examples, the row multiplexing traces 1202 provide an electric voltage to one acoustic transducer 108 at a time. In certain examples, the row multiplexing traces 1202 provide an electric voltage to acoustic transducers in succession along the row multiplexing traces 1202. In certain examples, it may be desirable to energize a single acoustic transducer 108 within the row multiplexing traces 1202without energizing a neighboring acoustic transducer to prevent receiving destructive interference of acoustic pressure waves from neighboring acoustic transducers 108.

[0091] In certain examples, the acoustic transducer array assembly 100 includes eight or twelve row multiplexing traces 1202 configured to provide electrical connections within an acoustic transducer array assembly having an 8x12 arrangement of acoustic transducers 108. In certain examples, the transducer array assembly 100 includes sixteen or twenty-four row multiplexing traces 1202 configured to provide electrical connections within an acoustic transducer array assembly having an 16x24 arrangement of acoustic transducers 108. In certain examples, the transducer array assembly 100 includes more than twenty -four rows or columns that contain column multiplexing traces 1200 and / or row multiplexing traces 1202.

[0092] In certain examples, the column multiplexing traces 1200 and the row multiplexing traces 1200 provide the ability7to excite any single acoustic transducer 108 positioned on the acoustic transducer array assembly 100 by providing a specific column and row to provide electrical energy to.

[0093] In certain examples, it is desirable to utilize column multiplexing traces 1200 or row7multiplexing traces 1202 to decrease the number of PCB traces required to electrically connect acoustic transducers 108 positioned at each plated through hole 104. Furthermore, in certain examples, the use of utilize column multiplexing traces 1200 or row multiplexing traces 1202 decreases the cost of assembling the acoustic transducer array assembly 100. Further yet, in certain examples, the use of utilize column multiplexing traces 1200 or row7multiplexing traces 1202 decreases the time required to assemble the acoustic transducer array assembly 100.

[0094] FIG. 22 shows a flow diagram of a method for providing acoustic pressure waves to at least one sample location 1400.

[0095] The method 1400 includes a first step 1402 of providing an acoustic transducer array assembly 100 including at least one piezoelectric element 114 that receives an electric voltage between at least one signal electrode 110 and at least one ground electrode 111.

[0096] The method includes a second step 1404 of using the at least one signal electrode 110 to and the at least one ground electrode 111 to provide a voltage to the at least one piezoelectric element 114. In some embodiments, the at least one signal electrode 110 and the at least one ground electrode 111 provide the voltage to the at leastone piezoelectric element 114 at a single location. In some embodiments, the at least one signal electrode 110 and the at least one ground electrode 111 provide the voltage to the at least one piezoelectric element 114 at a plurality of locations.

[0097] The method includes a third step 1406 of using the at least one piezoelectric element 114 to convert the voltage into acoustic pressure waves. The at least one piezoelectric element 114 is configured to receive the voltage from the signal electrode 110 and the ground electrode 111 and expand or contract to produce the acoustic pressure waves.

[0098] The method includes a fourth step 1408 of projecting the acoustic pressure waves to at least one sample location, wherein at least one signal reflection of the acoustic pressure waves is minimized due to an acoustic impedance match between an acoustic impedance of at least one piezoelectric element 114 and a target sample. In certain examples, acoustic pressure waves are generated by the acoustic transducer array assembly 100 are transmitted within an electronic system 1500 as shown in FIG. 24. In this example, it is desirable to maximize desired signal reflections that are amplified by the signal receiving amplifier 1514 and transmitted to the multiplexer 1502 when the switch 1504 is in a receiving position. In this example, it is desirable to minimize unintended signal reflections that are caused by impedance mismatches between adjacent layers or interfaces. In some embodiments the acoustic impedance match is obtained by providing a matching layer 106 or an acoustic transducer matching layer 304 for each individual acoustic transducer 108.

[0099] FIG. 23 shows a schematic illustration of an electronic system 1500 for operating the acoustic transducer array assembly 100.

[0100] The acoustic transducer array assembly 100 is provides acoustic pressure waves to a target sample as discussed above. Furthermore, the acoustic transducer array assembly 100 transmits and receives signals from a multiplexor 1502. In certain examples, the input voltage signal is provided to the acoustic transducer array assembly that includes a frequency range between 1 MHz to 20 MHz

[0101] The multiplexor 1502 is configured to receive input signals from the acoustic transducer array assembly 100 or provide output signals to the acoustic transducer array assembly 100. The multiplexor 1502 can forward a selected signal received from the acoustic transducer array or the signal receiving amplifier 1514 to an output line within the electronic system 1500. In certain examples, the multiplexor 1502 may combinemultiple input signals into a single output signal. In certain examples, the multiplexor 1502 can be implemented using logic gates.

[0102] The signal output from the multiplexor 1502 is received by a switch 1504 that determines whether to transmit a signal received from the multiplexor 1502 to a signal transmitting amplifier 1506 or transmit a signal received from a signal receiving amplifier 1514 to the multiplexor 1502. In certain examples, the switch 1504 includes an RX switch and / or a transmit / receive (TR) switch.

[0103] The signal transmitting amplifier 1506 is configured to receive a signal from the multiplexor 1502 when the switch 1504 is in a signal transmission position. The signal transmitting amplifier 1506 increases the amplitude of signals received by the multiplexor 1502 and transmits the signal to the signal capture device 1508.

[0104] The signal capture device 1508 captures an electronic signal received by the signal transmitting amplifier 1506 and converts the analog signal to a digital signal. The signal capture device 1508 is desirable to convert real-world signals (such as audio, video, or other sensor data) into digital signals that can be processed by a computing device 1510.

[0105] The computing device 1510 receives signals from the signal capture device and processes the signals prior to transmitting the signals to an analog signal generating device 1512. In certain examples, the signals include chirps or pulse signals. In certain examples, the chirps or pulse signals include a square voltage signal.

[0106] In certain examples the computing device 1510 includes at least one processing device, such as a central processing unit (CPU). In certain examples, the computing device also includes a system memory and a system bus that couples various system components including the system memory’ to the processing device. The system bus is one of any number of types of bus structures including a memory bus, or memory controller; a peripheral bus; and a local bus using any’ of a variety7of bus architectures.

[0107] The system memory includes read only memory7and random-access memory. A basic input / output system containing the basic routines that act to transfer information within a computing device, such as during start up. is typically stored in the read only memory. Some embodiments include non-transitory media. Additionally, such computer readable storage media can include local storage or cloud-based storage.

[0108] In some embodiments, a user provides inputs to the computing device 1510 through one or more input devices. These inputs can include commands to generatesignals at the acoustic transducer array assembly 100. The input devices are often connected to the processing device through an input / output interface that is coupled to the system bus. These input devices can be connected by any number of input / output interfaces, such as a parallel port, serial port, game port, or a universal serial bus. Wireless communication between input devices and the interface is possible as well, and includes infrared, BLUETOOTH® wireless technology, 802. 1 la / b / g / n, cellular, or other radio frequency communication systems in some possible embodiments.

[0109] Computer readable storage media includes volatile and nonvolatile, removable and non-removable media implemented in any device configured to store information such as computer readable instructions, data structures, program modules or other data. Computer readable storage media includes, but is not limited to, random access memory, read only memory, electrically erasable programmable read only memory, flash memory or other memory technology, compact disc read only memory, digital versatile disks or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and that can be accessed by the computing device. Computer readable storage media does not include computer readable communication media.

[0110] The analog signal generating device 1512 receives digital signals produced by the computing device 1510 and converts the digital signal to an analog signal. In certain examples, the analog signal generating device 1512 generates analog waveforms, such as audio signals or control signals, from digital data.[OHl] The signal receiving amplifier 1514 is configured to receive an analog signal from the analog signal generating device 1512, amplify the signal, and transmit the signal to the multiplexor 1502 when the switch 1504 is in a signal receiving position.

[0112] The above description is illustrative and is not restrictive. Many variations of the invention will become apparent to those skilled in the art upon review of the disclosure. The scope of the invention should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the pending claims along with their full scope or equivalents.

[0113] One or more features from any embodiment may be combined with one or more features of any other embodiment without departing from the scope of the invention.

Claims

WHAT IS CLAIMED IS:

1. An acoustic transducer array assembly configured to provide acoustic pressure waves to at least one sample location comprising: a printed circuit board including: at least one plated through hole; and a matching layer including an acoustic medium configured to provide an acoustic impedance match between an acoustic impedance of at least one piezoelectric element and a target sample: and at least one acoustic transducer including: at least one signal electrode electrically connected to the at least one plated through hole and acoustically coupled to the matching layer; at least one ground electrode electrically connected to the at least one plated through hole and acoustically coupled to the matching layer; and the at least one piezoelectric element being electrically connected to the at least one signal electrode and the at least one ground electrode, wherein the at least one piezoelectric element is configured to produce the acoustic pressure waves when an electric voltage is applied between the at least one signal electrode and the at least one ground electrode to the piezoelectric element.

2. The acoustic transducer array assembly of claim 1, wherein the matching layer includes a polymeric material.

3. The acoustic transducer array assembly of claim 2, wherein the polymeric material includes at least one of polyimide, polyester, polyphenylene oxide, or polypropylene.

4. The acoustic transducer array assembly according to any one of claims 1-3. wherein the printed circuit board includes a plurality of plated through holes arranged in a rectilinear array.

5. The acoustic transducer array assembly of claim 4, wherein the at least one acoustic transducer includes a plurality of signal electrodes, a plurality of ground electrodes, and a plurality of piezoelectric elements arranged in the rectilinear array.

6. The acoustic transducer array assembly of claim 5, wherein the rectilinear array includes a row-column configuration having at least one column and at least one row, wherein the at least one column includes the plurality of signal electrodes, the plurality of ground electrodes, and the plurality of piezoelectric elements electrically connected in a series connection.

7. The acoustic transducer array assembly of claim 5, wherein the rectilinear array includes a row-column configuration having at least one column and at least one row, wherein the at least one row includes the plurality of signal electrodes, the plurality of ground electrodes, and the plurality of piezoelectric elements electrically connected in a parallel connection.

8. The acoustic transducer array assembly according to any one of claims 1-7, wherein the printed circuit board includes a positive side and a negative side.

9. The acoustic transducer array assembly according to any one of claims 1-8. wherein acoustic connections within the acoustic transducer are arranged in a series connection.

10. The acoustic transducer array assembly according to any one of claims 1-9. wherein acoustic connections within the acoustic transducer are arranged in a parallel connection.

11. The acoustic transducer array assembly according to any one of claims 1-10, wherein the at least one piezoelectric element includes at least one piezoelectric disc.

12. The acoustic transducer array assembly according to any one of claims 1-11, wherein the at least one piezoelectric element includes at least one piezoelectric plate.

13. A method for providing acoustic pressure waves to at least one location, the method comprising: providing an acoustic transducer array assembly, wherein the acoustic transducer array assembly includes:at least one printed circuit board including at least one plated through hole and at least one matching layer including an acoustic medium configured to provide an acoustic impedance match between at least one piezoelectric element and at least one target sample; and at least one acoustic transducer including at least one signal electrode electrically connected to the at least one plated through hole and acoustically connected to the at least one matching layer, at least one ground electrode electrically connected to the at least one plated through hole and acoustically connected to the at least one matching layer, and at least one piezoelectric element electrically connected to the at least one signal electrode and the at least one ground electrode; applying an electric voltage between the at least one signal electrode and the at least one ground electrode to the at least one piezoelectric element; converting the electric voltage into the acoustic pressure waves; and projecting the acoustic pressure waves to the at least one location, wherein at least one signal reflection of the acoustic pressure waves is minimized due to the acoustic impedance match.

14. The method of claim 13, wherein the at least one matching layer includes a polymeric material.

15. The method of claim 14, wherein the polymeric material includes at least one of polyimide, polyester, polyphenylene oxide, or polypropylene.

16. The method according to any one of claims 13-15, wherein the printed circuit board includes a plurality of plated through holes arranged in a rectilinear array and a plurality of acoustic transducers that are configured to engage with the plurality of plated through holes.

17. The method according to any one of claims 13-16, further comprising projecting the acoustic pressure waves to the at least one location using a plurality of acoustic transducers in succession.

18. A method of making an acoustic transducer array assembly, the method comprising: providing the acoustic transducer array assembly, wherein the acoustic transducer array assembly includes a printed circuit board including at least one plated through hole and at least one matching layer configured to provide an acoustic impedance match between at least one piezoelectric element and at least one target sample; electrically connecting at least one signal electrode to the acoustic transducer array assembly and acoustically connecting the at least one signal electrode to the at least one matching layer; electrically connecting at least one ground electrode to the acoustic transducer array assembly and acoustically connecting the at least one ground electrode to the at least one matching layer; and electrically connecting the at least one piezoelectric element to the at least one signal electrode and the at least one ground electrode.

19. The method of claim 18, further comprising enclosing the acoustic transducer array assembly within an enclosure.

20. The method according to any one of claims 18-19, further comprising acoustically connecting at least one piezo backing material to a back side of the at least one piezoelectric element.

Images