Acoustic transducer assembly, method for producing an acoustic transducer assembly, and method of operating an acoustic transducer assembly
Patent Information
- Application Number
- PCT/EP2026/052973
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-02-19
- Filing Date
- 2026-02-05
- Publication Date
- 2026-08-27
Smart Images
Figure EP2026052973_27082026_PF_FP_ABST
Abstract
Description
[0001] P2025, 0112 WO N February 5, 2026
[0002] Description
[0003] ACOUSTIC TRANSDUCER ASSEMBLY, METHOD FOR PRODUCING AN ACOUSTIC TRANSDUCER ASSEMBLY, AND METHOD OF OPERATING AN ACOUSTIC TRANSDUCER ASSEMBLY
[0004] An acoustic transducer assembly, a method for producing an acoustic transducer assembly, and a method of operating an acoustic transducer assembly are specified herein.
[0005] Documents DE 102013217362 Al, DE 102009040264 Al,
[0006] DE 102006034997 Al, DE 102008016558 Al, DE 000069407794 T2, DE 102013211627 Al, DE 102006038598 Al, DE 102008017067 Al, DE 102005046173 Al, DE 000010347098 Al, DE 102018115294 Al, and DE 000029500074 U1 describe acoustic transducer
[0007] ass e mb lies .
[0008] An acoustic transducer assembly can be used as a sensor, for example as a proximity sensor, as a sensor for obj ect identification or obstacle detection, as a distance sensor, as a velocity sensor, as a sensor for testing or monitoring the structural integrity of materials, and / or as a fluid level sensor . For example, acoustic transducers can be used as parking sensors in cars or as distance sensors in robots . In the former case, the acoustic transducers are typically arranged on a car bumper, thereby exposing the acoustic transducer to external influences and / or altering the appearance of the car bumper, for example .
[0009] In order to increase their lifetime, e . g. in industrial applications, it may be desirable to protect acoustic transducers from environmental influences, such as mechanical forces, dust, moisture, and / or chemically reactiveP2025, 0112 WO N February 5, 2026
[0010] 2
[0011] substances . Further, in some applications it may be desirable to arrange the acoustic transducer such that it cannot be easily detected or tampered with. Moreover, it may be desirable to arrange the acoustic transducer such that it does not alter the appearance or structure of the device on which it is arranged.
[0012] At least one obj ect of certain embodiments is to provide a seamless acoustic transducer assembly. At least one further obj ect of certain embodiments is to provide a method for producing a seamless acoustic transducer assembly. At least one further obj ect of certain embodiments is to provide a method for operating a seamless acoustic transducer assembly.
[0013] These obj ects are solved by the acoustic transducer assembly, the method for producing an acoustic transducer assembly, and the method for operating an acoustic transducer assembly according to the independent claims . Further embodiments and further developments of the acoustic transducer assembly, the method for producing an acoustic transducer assembly, and the method for operating an acoustic transducer assembly are specified in the dependent claims .
[0014] According to an aspect, the acoustic transducer assembly comprises an acoustic transducer arranged on a medium. The acoustic transducer can be configured to transmit and / or receive an acoustic signal . For example, the acoustic transducer combines the functions of an acoustic transmitter for transmitting acoustic signals and of an acoustic receiver for receiving acoustic signals . For example, the acoustic transducer is configured for converting an electric signal into the acoustic signal and / or vice versa .P2025, 0112 WO N February 5, 2026
[0015] 3
[0016] For example, the acoustic transducer is an ultrasonic acoustic transducer . For example, the acoustic signal comprises or consists of acoustic waves . In particular, the acoustic signal and / or the acoustic waves are in an ultrasound spectral range . For example, the ultrasound spectral range comprises acoustic waves with frequencies of at least 20 kHz .
[0017] For example, the acoustic transducer is configured for a time-of-f light measurement and / or for a Doppler measurement . For example, the time-of-f light measurement can be used for measuring a distance between the acoustic transducer assembly and an external obj ect . For example, the time-of-f light measurement determines a time-of-f light of a pulse-like acoustic signal that is emitted from the acoustic transducer assembly, at least partially back-reflected by the external obj ect and subsequently detected by the acoustic transducer assembly. For example, the Doppler measurement can be used for measuring a velocity of the external obj ect, by comparing a frequency of the emitted acoustic signal with a frequency of the received acoustic signal, wherein the received acoustic signal comprises at least a part of the emitted acoustic signal that is back-reflected from a moving external ob j ect .
[0018] In particular, the medium is solid. For example, the medium comprises or consists of a metal, a plastic, a glass and / or a ceramic . For example, the medium can also comprise or consist of a composite material or multi-layered material such as wood, plywood, fiberboard, fiber enforced plastic or the like . The medium can enclose or completely enclose a volume, wherein the acoustic transducer is arranged, for example . A surface of the medium, for example a surface upon which the acoustic transducer is arranged, can form a closed surface .P2025, 0112 WO N February 5, 2026
[0019] 4
[0020] For example, the medium is sheet-like or board-like, wherein a thickness of the medium is smaller than a linear extension of the medium in transverse directions . Here and in the following, the transverse directions are directions parallel to a main extension plane of the medium or parallel to a tangential plane of the medium, on which the acoustic transducer is arranged. In particular, the thickness refers to a linear extension of the medium in a direction perpendicular to the main extension plane or the tangential plane . For example, the medium has a planar, curved, spherical, bent, angled, and / or a complex shape . For example, the medium is a car bumper, a robot chassis, a wall of a vessel, an appliance casing, a frame, a cell, or a housing part of a complex device .
[0021] For example, the medium separates an outside or primary side of the acoustic transducer assembly from an inside or secondary side of the acoustic transducer assembly. In particular, the acoustic transducer is arranged on the inside or secondary side of the acoustic transducer assembly. For example, on the inside the acoustic transducer is protected from external environmental influences that can occur or are present on the outside of the acoustic transducer assembly. The acoustic transducer can be configured for sensing external obj ects that are located on the outside or on the primary side of the acoustic transducer assembly.
[0022] According to a further aspect of the acoustic transducer assembly, the acoustic transducer is arranged on the medium, such that an acoustic signal is at least partially transmitted through the medium by the acoustic transducer and / or received through the medium by the acoustic transducer during operation. In particular, an outcoupling and / orP2025, 0112 WO N February 5, 2026
[0023] 5
[0024] incoupling surface for acoustic signals of the acoustic transducer is arranged on the medium. For example, acoustic signals that are generated by the acoustic transducer assembly are coupled out of the acoustic transducer assembly via a surface of the medium facing away from the acoustic transducer . For example, acoustic signals that are detected by the acoustic transducer assembly are coupled into the acoustic transducer assembly via the medium.
[0025] The acoustic transducer can be arranged directly on the medium. Alternatively, further elements, such as a carrier, a coupling means, a fastening means and / or a stiffening means that are described in detail below can be arranged between the acoustic transducer and the medium.
[0026] In particular, the medium has a low acoustic absorptance and a high acoustic transmittance for acoustic signals generated and / or detected by the acoustic transducer during operation. For example, the acoustic absorptance corresponds to a ratio between a power of the acoustic signal that is absorbed by the medium and a power of the acoustic signal that is incident on the medium. For example, the acoustic transmittance corresponds to a ratio between a power of the acoustic signal that is transmitted through the medium and the power of the acoustic signal that is incident on the medium. For example, the acoustic transmittance of the medium for acoustic waves generated and / or detected by the acoustic transducer during operation is at least 50%, or at least 70%, or at least 90% . For example, the acoustic absorptance of the medium for acoustic waves generated and / or detected by the acoustic transducer during operation is at most 50%, or at most 30%, or at most 10% .P2025, 0112 WO N February 5, 2026
[0027] 6
[0028] For example, the acoustic signal is generated, in particular completely and exclusively generated, by the acoustic transducer . For example, the medium is a passive medium. In particular, the medium does not participate or hardly participates in generating the acoustic signal . For example, the acoustic signal solely transits or traverses the medium to and / or from the acoustic transducer . For example, the medium and the acoustic transducer are not directly and / or not rigidly mechanically coupled.
[0029] It is also possible that the medium generates the acoustic signal that is coupled out of the acoustic transducer assembly, for example . In particular, a surface of the medium facing away from the acoustic transducer can be an active surface of the acoustic transducer assembly for generating the acoustic signal that is coupled out of the acoustic transducer assembly. In particular, the medium and the acoustic transducer are directly or indirectly mechanically coupled. For example, the medium and the acoustic transducer are rigidly coupled and / or the medium is rigid. For example, during operation of the acoustic transducer assembly one or more vibrational modes of the medium are excited that generate the acoustic signal that is coupled out of the acoustic transducer assembly.
[0030] It is also possible that the medium at least partially generates the acoustic signal that is coupled out of the acoustic transducer assembly. In particular, the acoustic transducer and the medium are mechanically coupled. For example, the coupling between the acoustic transducer and the medium is not rigid and / or the medium is not rigid. For example, during operation of the acoustic transducer assembly one or more vibrational modes of the medium are excited thatP2025, 0112 WO N February 5, 2026
[0031] 7
[0032] participate in generating the acoustic signal . In other words, a first part of the acoustic signal that is generated by the acoustic transducer can be transmitted through the medium while a second part of the acoustic signal that is generated by the acoustic transducer can be at least partially absorbed by the medium. The absorbed acoustic signal can excite vibrational modes in the medium that generate a third part of the acoustic signal . For example, the first part of the acoustic signal and the third part of the acoustic signal are coupled out from the acoustic transducer arrangement .
[0033] For example, the acoustic transducer assembly has a neutral point, a neutral line, and / or a neutral area, which upon operation of the acoustic transducer assembly does not or hardly undergoes any deformation and / or vibration. This neutral point, neutral line, and / or neutral area can be located inside the acoustic transducer, inside the medium, or between the acoustic transducer and the medium, for example .
[0034] For example, if the neutral point, neutral line and / or neutral area is located inside the acoustic transducer or between the acoustic transducer and the medium, then the medium is at least partially passive and does not participate or hardly participates in generating the acoustic signal that is coupled out of the acoustic transducer assembly. For example, this can be the case if the medium is not rigid and / or if the acoustic transducer and the medium are not rigidly coupled.
[0035] For example, if the neutral point, neutral line and / or neutral area is located inside the medium, then the medium is at least partially active and participates in generating theP2025, 0112 WO N February 5, 2026
[0036] 8
[0037] acoustic signal . For example, this can be the case if the medium is rigid and / or the acoustic transducer and the medium are rigidly coupled. For example, the closer the neutral point, neutral line and / or neutral area is located to a surface of the medium facing away from the acoustic transducer, the more the medium participates in generating the acoustic signal that is coupled out of the acoustic transducer assembly. By appropriately choosing dimensions, a stiffness and / or a thickness of the medium, and / or by choosing a coupling type or coupling method for coupling the medium and the acoustic transducer, the location of the neutral point, neutral line, and / or neutral area in the acoustic transducer assembly can be adjusted and / or optimized.
[0038] According to an embodiment, the acoustic transducer assembly comprises an acoustic transducer arranged on a medium, such that an acoustic signal is at least partially transmitted through the medium by the acoustic transducer and / or received through the medium by the acoustic transducer during operation .
[0039] The acoustic transducer assembly described herein is based on the idea to provide a seamless acoustic transducer assembly. In particular, the acoustic transducer is arranged on an inside of the medium while being configured as a sensor for sensing external obj ects and / or their properties on an outside of the medium. This acoustic transducer assembly allows to physically hide the acoustic transducer behind a structure or medium, without losing or significantly worsening its acoustic properties .P2025, 0112 WO N February 5, 2026
[0040] 9
[0041] In particular, the acoustic transducer assembly disclosed herein can protect the acoustic transducer from environmental influences on the outside of the assembly, thereby improving its longevity, reliability and / or robustness, for example . Further, the acoustic transducer assembly disclosed herein allows for sensing, e . g. distance or level measurements, without altering the appearance or structure of the assembly from the outside . This can be particularly useful in applications where aesthetics and / or fluid dynamics, e . g. aerodynamics, of the assembly are important .
[0042] Moreover, the acoustic transducer assembly described herein can provide enhanced safety in industrial settings, where seamless or hidden sensors can monitor devices or hazardous areas without exposing the sensor to potential damage or interference from external elements . Lastly, the acoustic transducer assembly described herein can be used in security systems, e . g. to detect intrusions or unauthorized access, without being easily detected or tampered with.
[0043] According to a further aspect of the acoustic transducer assembly, the acoustic transducer comprises or consists of an electro-magnetic transducer . For example, the transducer comprises a coil that converts an electric current into a magnetic field that is further converted into a deflection of a magnetic actuator, or vice versa .
[0044] According to a further aspect of the acoustic transducer assembly, the acoustic transducer comprises or consists of an electro-strictive transducer . For example, the acoustic transducer comprises or consists of a dielectric material that changes its shape when an electric field is applied, or vice versa .P2025, 0112 WO N February 5, 2026
[0045] 10
[0046] According to a further aspect of the acoustic transducer assembly, the acoustic transducer comprises or consists of a capacitive transducer . For example, the capacitive transducer comprises a membrane and an electrode that are substantially parallel to each other and that form a capacitor . In particular, by applying a voltage between the electrode and the membrane, the membrane can be displaced.
[0047] According to a further aspect of the acoustic transducer assembly, the acoustic transducer comprises or consists of a piezoelectric transducer . For example, the piezoelectric transducer comprises or consists of a piezoelectric material that generates an electric polarization when a mechanical stress is applied, or vice versa . For example, the acoustic transducer comprises or consists of a lead-containing piezoelectric material, a lead-free piezoelectric material, a PFAS-containing piezoelectric material, or a PFAS-free piezoelectric material . For example, the acoustic transducer is a bare piezo element, such as a piezo crystal, a piezo thin-film or a stack of piezo thin-films .
[0048] According to a further aspect of the acoustic transducer assembly, the piezoelectric transducer comprises or consists of a ceramic piezoelectric element, a polymeric piezoelectric element, a composite piezoelectric element, and / or a piezoelectric thin-film element .
[0049] According to a further aspect of the acoustic transducer assembly, the acoustic transducer is arranged on a carrier structure . In particular, the carrier structure mechanically stabilizes the acoustic transducer . For example, the carrier structure is arranged between the medium and the acousticP2025, 0112 WO N February 5, 2026
[0050] 11
[0051] transducer . Alternatively or in addition, the carrier structure can cover surfaces of the acoustic transducer that are not covered by the medium. For example, the carrier structure covers sidewalls of the acoustic transducer . For example, the carrier structure fully encloses the acoustic transducer .
[0052] According to a further aspect of the acoustic transducer assembly, the carrier structure is pot-shaped. In particular, the pot-shaped carrier structure comprises a recess . For example, the acoustic transducer is arranged in the recess of the pot-shaped carrier structure .
[0053] According to a further aspect, the acoustic transducer assembly further comprises an electronic circuit for operating the acoustic transducer . For example, the electronic circuit is configured for controlling, driving and / or reading out electric signals from the acoustic transducer . In particular, the electronic circuit comprises active electronics, such as an amplifier . For example, the electronic circuit is arranged on a circuit board that is electrically connected to the acoustic transducer .
[0054] According to a further aspect of the acoustic transducer assembly, the acoustic transducer and the electronic circuit are arranged inside the pot-shaped carrier structure . In particular, the acoustic transducer and the electronic circuit are arranged in the recess of the pot-shaped carrier structure . For example, the acoustic transducer is arranged at the bottom of the recess, while the electric circuit is arranged on a circuit board, that is separated from the acoustic transducer by a sealing. For example, the acousticP2025, 0112 WO N February 5, 2026
[0055] 12
[0056] transducer is fully enclosed by the carrier structure and the sealing .
[0057] According to a further aspect, the acoustic transducer assembly further comprises at least one further acoustic transducer that is arranged on the medium. For example, the acoustic transducer assembly comprises an array of acoustic transducers that is arranged on the medium. All features that are disclosed for the acoustic transducer are also disclosed for the one or more further acoustic transducers . For example, the acoustic transducer is configured for emitting acoustic signals, while one or more further acoustic transducers are configured for detecting acoustic signals, or vice versa . In particular, the acoustic transducer and the further acoustic transducer are arranged on the medium such that acoustic signals do not propagate or marginally propagate directly from the acoustic transducer to the further acoustic transducer via the medium, or vice versa .
[0058] According to a further aspect of the acoustic transducer assembly, the medium seals the acoustic transducer . For example, the medium hermetically seals the acoustic transducer . For example, the medium forms an enclosure for the acoustic transducer . In particular, the medium physically separates the acoustic transducer that is arranged on the inside of the medium from the outside of the medium.
[0059] According to a further aspect of the acoustic transducer assembly, the medium forms an enclosure that hermetically seals the acoustic transducer . In particular, here and in the following "hermetically seals" refers to a medium that is configured for preventing an ingress of liquids, moisture, gases, dust and / or harmful substances into the inside of theP2025, 0112 WO N February 5, 2026
[0060] 13
[0061] acoustic transducer assembly, e . g. under normal operating conditions of the acoustic transducer assembly. For example, the medium is configured for protecting the acoustic transducer from liquids, moisture, gases, dust and / or harmful substances .
[0062] According to a further aspect of the acoustic transducer assembly, the medium is shaped for guiding acoustic signals to and / or from the acoustic transducer . In particular, the medium is shaped in the vicinity of the acoustic transducer for guiding acoustic signals through the medium that are transmitted and / or detected by the acoustic transducer . For example, the medium is thinned where the acoustic transducer is arranged. For example, the medium is thinned to a minimal thickness, such that the structural integrity of the medium is maintained while maximizing the transmittance of the medium for the acoustic signal .
[0063] For example, the medium comprises a surface structure in and / or around an area where the acoustic transducer is arranged. For example, the surface structure comprises or consists of a plurality of pillars and / or recesses that are formed adj acent to the area where the acoustic transducer is arranged. For example, the surface structure is configured as an acoustic lens or as an acoustic meta-lens for collimating and / or focusing the acoustic signal . For example, the surface structure defines or restricts, or is configured to define or restrict a deformation or vibration of the medium to an area adj acent to the acoustic transducer during operation.
[0064] According to a further aspect of the acoustic transducer assembly, a neutral point, a neutral line and / or a neutral area that is not deformed during operation is located insideP2025, 0112 WO N February 5, 2026
[0065] 14
[0066] the medium, inside the acoustic transducer, or between the medium and the acoustic transducer .
[0067] According to a further aspect of the acoustic transducer assembly, the medium is shaped for adjusting a location of the neutral point, neutral line, and or neutral area .
[0068] According to a further aspect of the acoustic transducer assembly, the medium comprises a recess and the acoustic transducer is arranged in the recess . For example, a thickness of the medium in the recess is minimal, such that the structural integrity of the medium is maintained while maximizing the transmittance of the medium for the acoustic signal .
[0069] According to a further aspect, the acoustic transducer assembly further comprises a stiffening means . For example, the stiffening means is configured for guiding acoustic signals through the medium to and / or from the acoustic transducer . For example, the stiffening means comprises or causes an acoustic impedance mismatch, such that the acoustic signal is at least partially reflected and / or refracted. For example, the stiffening means defines or restricts, or is configured to define or restrict a deformation or vibration of the medium to an area adj acent to the acoustic transducer during operation. For example, the stiffening means enhances an efficiency of the acoustic transducer assembly for generating and / or receiving acoustic signals at the outside of the medium.
[0070] In particular, the stiffening means increases the efficiency and / or a signal-to-noise ratio of the acoustic transducer assembly. The stiffening means can comprise one or moreP2025, 0112 WO N February 5, 2026
[0071] 15
[0072] stiffening elements . The stiffening elements can comprise or consist of different materials . Further, the stiffening elements can have different shapes . The stiffening elements can be arranged in an isotropic or anisotropic manner and can be configured for shaping the acoustic signal .
[0073] For example, the stiffening means prevents or reduces a propagation of acoustic signals in transverse directions . For example, the stiffening means comprises or consists of fibers, such as glass fibers or carbon fibers, that are arranged on the medium or integrated into the medium.
[0074] Alternatively or in addition, the stiffening means can comprise or consist of metal reinforcements . For example, the stiffening means is arranged in and / or in the vicinity of an area where the acoustic transducer is arranged on the medium. For example, the stiffening means increases a structural stability and / or a structural integrity of the medium, in particular if the medium is thinned in a region where the acoustic transducer is arranged.
[0075] According to a further aspect of the acoustic transducer assembly, the stiffening means has a higher characteristic specific acoustic impedance than the medium.
[0076] According to a further aspect of the acoustic transducer assembly, the stiffening means is arranged inside the medium, the stiffening means is arranged between the medium and the acoustic transducer, and / or the stiffening means is arranged inside the acoustic transducer or is part of the acoustic transducer .
[0077] According to a further aspect of the acoustic transducer assembly, the stiffening means is configured for changing aP2025, 0112 WO N February 5, 2026
[0078] 16
[0079] propagation direction of the acoustic signal during operation .
[0080] According to a further aspect, the acoustic transducer assembly further comprises a fastening means configured for mounting the acoustic transducer on the medium. In particular, the fastening means is arranged between the medium and the acoustic transducer . In particular, the fasting means is configured for mechanically fixing the acoustic transducer on the medium. For example, the fastening means is further configured as the stiffening means, or vice versa . For example, the fastening means comprises or consists of a means for a snap-fit connection, a screw connection, a threaded insert, a glue, and / or a resin. Further, the fastening means can be fixed inside the medium by overmolding, for example, thereby providing an acoustic transducer assembly where the acoustic transducer can be easily picked and placed on or inside the medium.
[0081] According to a further aspect, the acoustic transducer assembly further comprises a coupling means arranged between the medium and the acoustic transducer . For example, the coupling means comprises or consists of a glue, e . g. a fiber reinforced glue, a matching layer, and / or an acoustic gel .
[0082] According to a further aspect of the acoustic transducer assembly, the coupling means is configured for increasing an acoustic coupling between the acoustic transducer and the medium. For example, the coupling means increases an efficiency and / or a signal-to-noise ratio of the acoustic transducer assembly. For example, the coupling means increases a contact area between the transducer and the medium. For example, an active surface of the acousticP2025, 0112 WO N February 5, 2026
[0083] 17
[0084] transducer is fully in contact with the medium via the coupling means .
[0085] According to a further aspect of the acoustic transducer assembly, the acoustic transducer is encapsulated with a potting material that covers all surfaces of the acoustic transducer that are not covered by the medium. For example, the potting material comprises or consists of a resin. In particular, the potting material is in contact, e . g. in direct contact, with the medium and the acoustic transducer .
[0086] An element that is configured as a stiffening means can also be configured as a fastening means and / or a coupling means . Further, an element that is configured as a fastening means can also be configured as a stiffening means and / or a coupling means . Moreover, an element that is configured as a coupling means can also be configured as a stiffening means and / or a fastening means .
[0087] Further, a method for producing an acoustic transducer assembly is specified herein. In particular, the method can be used for producing an acoustic transducer assembly as described above . All features of the acoustic transducer assembly are also disclosed for the method for producing an acoustic transducer assembly, and vice versa .
[0088] According to an embodiment, the method for producing an acoustic transducer assembly comprises the steps of :
[0089] - preparing a portion of a surface of a medium for arranging an acoustic transducer thereon,
[0090] - arranging the acoustic transducer on the portion of the surface of the medium.P2025, 0112 WO N February 5, 2026
[0091] 18
[0092] For example, the portion of the surface of the medium is prepared by thinning the medium in the region where the acoustic transducer is arranged in a later step .
[0093] Alternatively or in addition, a surface structure can be formed in the surface of the medium, such as a recess or an acoustic meta-lens . For example, arranging the acoustic transducer on the portion of the surface of the medium comprises mounting the acoustic transducer on the medium, e . g. by using the fastening means .
[0094] According to a further aspect of the method for producing an acoustic transducer assembly, the step of preparing a portion of a surface of the medium comprises arranging a stiffening means on and / or in the medium. For example, the stiffening means comprises or consist of stiffening element, such as a metal reinforcement and / or a fiber reinforced resin.
[0095] According to a further aspect, the method for producing an acoustic transducer assembly comprises a further step of encapsulating the acoustic transducer after arranging it on the medium. For example, the acoustic transducer is encapsulated with a potting material .
[0096] Further, a method for operating an acoustic transducer assembly is specified herein. In particular, the method can be used for operating an acoustic transducer assembly as described above . All features of the acoustic transducer assembly are also disclosed for the method for operating an acoustic transducer assembly, and vice versa .
[0097] According to an embodiment, the method of operating an acoustic transducer assembly as described above comprises the steps of :P2025, 0112 WO N February 5, 2026
[0098] 19
[0099] - at least partially transmitting an acoustic signal through the medium by applying an electric signal to the acoustic transducer,
[0100] - detecting by means of the acoustic transducer assembly at least a part of the transmitted acoustic signal that is back-reflected by a target on a side of the medium facing away from the acoustic transducer . For example, the acoustic transducer and / or a further acoustic transducer is used for detecting the back-reflected acoustic signal .
[0101] Further advantageous embodiments and further developments of the acoustic transducer assembly, the method of producing an acoustic transducer assembly, and the method for operating an acoustic transducer assembly become apparent from the following exemplary embodiments described in connection with the Figures .
[0102] Figures 1 to 13 show schematic cross sections of acoustic transducer assemblies according to different exemplary embodiments .
[0103] Figures 14 and 15 show a schematic plan view and a schematic cross section of an acoustic transducer assembly according to a further exemplary embodiment .
[0104] Figures 16 to 18 show schematic cross sections of acoustic transducer assemblies according to further exemplary embodiments .
[0105] Figure 19 shows a schematic exploded view of an acoustic transducer assembly according to a further exemplary embodiment .P2025, 0112 WO N February 5, 2026
[0106] 20
[0107] Figure 20 shows a schematic cross section of an acoustic transducer assembly and a method for operating it according to an exemplary embodiment .
[0108] Figures 21 to 24 show schematic perspective views of acoustic transducer assemblies according to further exemplary embodiments .
[0109] Figure 25 shows a schematic cross section of an acoustic transducer assembly according to a further exemplary embodiment .
[0110] Figure 26 shows a schematic perspective view of a part of an acoustic transducer assembly according to an exemplary embodiment .
[0111] Figures 27 and 28 show simulation results of a deformation of a medium of an acoustic transducer assembly according to different exemplary embodiments .
[0112] Figures 29 to 35 show schematic plan views of a stiffening element of an acoustic transducer assembly according to different exemplary embodiments .
[0113] Figure 36 shows a schematic cross section of an acoustic transducer assembly and a method for operating it according to an exemplary embodiment .
[0114] Elements that are identical, similar, or have the same effect, are denoted by the same reference signs in the Figures . The Figures and the proportions of the elements shown in the Figures are not to be regarded as true to scale . Rather, individual elements, in particular layer thicknesses,P2025, 0112 WO N February 5, 2026
[0115] 21
[0116] may be shown exaggeratedly large for better representability and / or better understanding.
[0117] The acoustic transducer assembly 1 according to the exemplary embodiment in figure 1 comprises a medium 3 with a main extension plane 33 extending in transverse directions x, y on which an acoustic transducer 2 is arranged. The acoustic transducer 2 is configured for transmitting and / or receiving an acoustic signal S (c . f . figure 20) in the ultrasonic spectral range . The acoustic transducer 2 comprises or consists of an electro-magnetic, an electro-strictive, a capacitive and / or a piezoelectric element for converting an electric signal into the acoustic signal S and / or vice versa .
[0118] The medium 3 comprises or consists of metal or plastic . For example, the medium 3 is an outer part of a chassis, case or housing of a complex device . For example, the medium 3 is a car bumper, a part of a car bumper, a robot chassis or a tank wall . An area of the main extension plane 33 of the medium 3 is larger, for example by at least a factor of ten, than an area of an out-coupling and / or in-coupling surface for acoustic signals of the acoustic transducer 2.
[0119] The acoustic transducer 2 is arranged on the medium 3, such that acoustic signals S are at least partially transmitted through the medium 3 by the acoustic transducer 2 during operation and / or such that acoustic signals S are received through the medium 3 by the acoustic transducer 2 during operation. In particular, the acoustic transducer 2 emits the acoustic signals S in longitudinal direction z and / or receives the acoustic signal S from a direction opposite to the longitudinal direction z during operation. The medium 3 can also participate in generating the acoustic signal S . ForP2025, 0112 WO N February 5, 2026
[0120] 22
[0121] example, the acoustic transducer 2 is coupled to the medium 3 such that during operation the acoustic transducer 2 excites vibrations in the medium 3 that at least partially form the acoustic signal S that is coupled out of the acoustic transducer assembly 1.
[0122] The medium 3 separates and outside 0 of the acoustic transducer assembly 1 from an inside I of the acoustic transducer assembly 1. For example, a surface of the medium 3 facing away from the acoustic transducer 2 marks a boundary between the outside 0 and the inside I of the acoustic transducer assembly 1. The acoustic transducer 2 is arranged on the inside I of the acoustic transducer assembly 1. In particular, the medium 3 seals or encapsulates the acoustic transducer 2, such that it is protected from the external environment on the outside 0. For example, the medium 3 seals off the outside 0 from the inside I . For example, the acoustic transducer 2 is configured for detecting an external obj ect T (c . f . figure 20) that is located on the outside 0 of the acoustic transducer assembly 1.
[0123] The acoustic transducer assembly 1 contains a neutral point, a neutral line, and / or a neutral area, which upon operation of the acoustic transducer assembly 1 does not or hardly undergoes any deformation. This neutral point, neutral line, and / or neutral area can be located inside the acoustic transducer 2, inside the medium 3, or between the acoustic transducer 2 and the medium 3 .
[0124] Compared to the acoustic transducer assembly 1 described in connection with figure 1, the acoustic transducer assembly 1 according to the exemplary embodiment in figure 2 comprises a further acoustic transducer 21 that is arranged on the mainP2025, 0112 WO N February 5, 2026
[0125] 23
[0126] extension plane 33 of the medium 3. For example, the acoustic transducer 2 is configured for emitting acoustic signals S, whereas the further acoustic transducer 21 is configured for detecting acoustic signals S, or vice versa . It is also possible that acoustic transducer 2 and the further acoustic transducer 21 are configured for both, emitting and detecting acoustic signals S . The acoustic transducer assembly 1 can also comprise three or more acoustic transducers 2, 21 that are arranged on the main extension plane 33 of the medium 3 in the form of an array, for example .
[0127] The acoustic transducer 2 and the further acoustic transducer 21 can be identical or different . For example, the acoustic transducer 2 and the further acoustic transducer 21 are based on the same physical principle or on different physical principles for emitting and / or detecting acoustic signals S . Further, the acoustic transducer 2 and the further acoustic transducer 21 can comprise the same or different materials . For example, the acoustic transducer 2 and the further acoustic transducer 21 can have the same shape and / or size, or can have a different shape and / or size .
[0128] Compared to the acoustic transducer assembly 1 described in connection with figure 1, the acoustic transducer assembly 1 according to the exemplary embodiment in figure 3 further comprises a potting material 9 that covers all surfaces of the acoustic transducer 2 that are not covered by the medium 3. The medium 3 and the potting material 9 together fully enclose the acoustic transducer 2 and protect the acoustic transducer 2 from harmful substances, for example . For example, the potting material 9 comprises or consists of a resin. The potting material 9 is further configured as a fastening means 7 for mechanically fixing the acousticP2025, 0112 WO N February 5, 2026
[0129] 24
[0130] transducer 2 on the medium 3. Moreover, the potting material 9 is further configured as a stiffening means 6 that is configured for increasing a mechanical stability and / or rigidity of the medium 3 in the region where the acoustic transducer 2 is arranged. For example, the potting material 9 can be used to adjust the position of the neutral point, the neutral line, and / or the neutral area in the acoustic transducer assembly 1.
[0131] Compared to the acoustic transducer assembly 1 described in connection with figure 1, the acoustic transducer assembly 1 according to the exemplary embodiment in figure 4 further comprises a carrier structure 4. The carrier structure 4 is configured for mechanically stabilizing the acoustic transducer 2. For example, the carrier structure 4 comprises or consists of a metal plate or a plastic plate . The carrier structure 4 is arranged between the medium 3 and the acoustic transducer 2 . Alternatively or in addition, the carrier structure 4 can also be arranged on a side of the acoustic transducer 2 facing away from the medium 3. The carrier structure 4 can fully enclose the acoustic transducer 2.
[0132] Compared to the acoustic transducer assembly 1 described in connection with figure 4, the acoustic transducer assembly 1 according to the exemplary embodiment in figure 5 comprises a pot-shaped carrier structure 4. In particular, the pot-shaped carrier structure 4 comprises a recess 41 at the bottom of which the acoustic transducer 2 is arranged.
[0133] In addition to the acoustic transducer assembly 1 described in connection with figure 5, the acoustic transducer assembly 1 according to the exemplary embodiment in figure 6 further comprises an electronic circuit 5. The electronic circuit 5P2025, 0112 WO N February 5, 2026
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[0135] is electrically connected to the acoustic transducer 2 and configured for operating the acoustic transducer 2. In particular, the electronic circuit 5 comprises an amplifier .
[0136] The electronic circuit 5 is arranged on a circuit board that in turn is arranged in the recess 41 of the pot-shaped carrier structure 4. The electronic circuit 5 is separated from the acoustic transducer 2 by a sealing 51. The sealing 51 and the carrier structure 4 fully enclose the acoustic transducer 2 .
[0137] Compared to the acoustic transducer assembly 1 described in connection with figure 1, the medium 3 of the acoustic transducer assembly 1 according to the exemplary embodiment in figure 7 is thinned in a region where the acoustic transducer 2 is arranged. Specifically, the medium 3 comprises a recess 31, in particular in a surface corresponding to the main extension plane 33 of the medium 3, where a thickness D of the medium 3 is reduced. The acoustic transducer 2 is arranged in the recess 31. Due to the recess 31 an acoustic transmittance of the medium 3 for the acoustic signal S emitted and / or detected by the acoustic transducer 2 is increased compared to a medium without the recess 31, thereby increasing a signal-to-noise ratio of the acoustic transducer assembly 1. For example, in the recess 31 the thickness D of the medium 3 is minimal, such that a structural integrity of the medium 3 is maintained and / or such that an optical appearance of the medium 3 from the outside 0 of the acoustic transducer assembly 1 is homogeneous, e . g. the recess 31 is not visible from the outside 0. For example, in the recess 31 the thickness D of the medium 3 is minimal, such that the acoustic transmittance of the medium 3 is maximized. For example, the recess 31 isP2025, 0112 WO N February 5, 2026
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[0139] configured for optimizing a position of the neutral point, neutral line or neutral area of the acoustic transducer ass e mb 1 y 1 .
[0140] Compared to the acoustic transducer assembly 1 described in connection with figure 7, the recess 31 in the main extension plane 33 of the medium 3 of the acoustic transducer assembly 1 according to the exemplary embodiment in figure 8 has angled side walls . In other words, a thickness D of the medium 3 changes continuously and / or smoothly along a crosssection of the recess 31. This can increase a stability of the medium 3 compared to the acoustic transducer assembly 1 described in connection with figure 7, for example .
[0141] Compared to the acoustic transducer assembly 1 described in connection with figure 1, the main extension plane 33 of the medium 3 of the acoustic transducer assembly 1 according to the exemplary embodiment in figure 9 comprises a surface structure 32. The surface structure 32 comprises a plurality of pillars and / or recesses for guiding acoustic signals S through the medium 3. In particular, a linear extension of the pillars and / or recesses is smaller than a wavelength of the acoustic signal S . For example, the surface structure 32 forms an acoustic meta-lens for focusing and / or collimating acoustic signals S that are emitted and / or detected by the acoustic transducer 2. For example, the surface structure 32 reduces or prevents a propagation of the acoustic signal S through the medium 3 in transverse directions x, y that are perpendicular to the longitudinal direction z .
[0142] Alternatively or in addition, the surface structure 32 is configured for adjusting the location of the neutral point, neutral line and / or neutral area . For example, the surfaceP2025, 0112 WO N February 5, 2026
[0143] 27
[0144] structure 32 shifts the location of the neutral point, neutral line and / or neutral area towards a surface of the medium 3 facing away from the acoustic transducer 2 . For example, the surface structure 32 reduces or minimizes a damping of the acoustic signal S by the medium 3 during operation. In this case dimensions of the surface structure can be larger than the wavelength of the acoustic signal S and / or are not related to the wavelength of the acoustic signal S .
[0145] Compared to the acoustic transducer assembly 1 described in connection with figure 1, the acoustic transducer assembly 1 according to the exemplary embodiment in figure 10 further comprises a stiffening means 6. The stiffening means 6 is arranged inside the medium 3 in an area where the acoustic transducer 2 is arranged. The stiffening means 6 is configured for guiding acoustic signals S in longitudinal direction z through the medium 3, in particular to and / or from the acoustic transducer 2 .
[0146] Alternatively or in addition, the stiffening means 6 is configured for shifting the location of the neutral point, neutral line and / or neutral area within the acoustic transducer assembly 1. The stiffening means 6 comprises a plurality of fibers, such as glass, carbon and / or metal fibers, that are embedded in the medium 3.
[0147] The stiffening means 6 can increase a structural stability of the medium 3, in particular if used in combination with the thinned medium 3 or with the recess 31 in the medium 3 as described in connection with figures 7 and 8. Further, the stiffening means 6 can be configured for shaping the propagation of the acoustic signal S inside the medium 3,P2025, 0112 WO N February 5, 2026
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[0149] thereby allowing for an optimized wave propagation predominantly in the longitudinal direction z . The stiffening means 6 can comprise on or more elements that can comprise the same or different materials, and / or that can have the same or different shapes . The stiffening means 6 can be arranged in an isotropic or anisotropic manner, thereby allowing to shape the propagation of the acoustic signal S in transverse directions x, y.
[0150] Compared to the acoustic transducer assembly 1 described in connection with figure 10, the stiffening means 6 of the acoustic transducer assembly 1 according to the exemplary embodiment in figure 11 is rod or plate shaped. In particular, the rod or plate is formed of a different material than the medium 3 and embedded into the medium 3.
[0151] Compared to the acoustic transducer assembly 1 described in connection with figure 10, the stiffening means 6 of the acoustic transducer assembly 1 according to the exemplary embodiment in figure 12 is arranged on the main extension plane 33 of the medium 3. In particular, the stiffening means 6 is ring shaped and completely surrounds the acoustic transducer 2 in transverse directions x, y, such that there is a gap between the stiffening means 6 and the acoustic transducer 2. For example, the stiffening means 6 is a metal ring or an annular metal disc . The stiffening means 6 can be axially symmetric with respect to the longitudinal direction z, or the stiffening means 6 can have an axial asymmetry with respect to the longitudinal direction z . For example, the stiffening means 6 is elongated and has a long axis and a short axis in transverse directions x, y, e . g. for shaping the acoustic signal S during operation.P2025, 0112 WO N February 5, 2026
[0152] 29
[0153] Compared to the acoustic transducer assembly 1 described in connection with figure 12, the stiffening means 6 of the acoustic transducer assembly 1 according to the exemplary embodiment in figure 13 is in direct contact with the acoustic transducer 2. In particular, there is no gap between the stiffening means 6 and the acoustic transducer 2.
[0154] Figure 14 on 15 show different cross sections of an acoustic transducer assembly 1 according to a further exemplary embodiment . The cross section in Figure 14 is in the transverse plane, i . e . in the xy-plane, and corresponds to a plan view of a plane inside the medium 3 that is parallel to the main extension plane 33 of the medium 3. Figure 15 shows a cross section in the xz-plane that includes the longitudinal direction z, analogous to figure 1. The medium 3 comprises a recess 31, analogous to the recess 31 described in connection with figure 7. Inside the recess 31 of the medium 3, a pot-shaped carrier structure 4 is arranged, analogous to the pot-shaped carrier structure 4 described in connection with figures 5 and 6. The acoustic transducer 2 is arranged at the bottom of the recess 41 of the pot-shaped carrier structure 4 .
[0155] The acoustic transducer assembly 1 shown in figures 14 and 15 further comprises a stiffening means 6, comprising a ringshaped element that is embedded into the medium 3, that extends into the recess 31 and encloses the carrier structure 4. Further, the stiffening means 6 comprises six spoke-like elements that are embedded into the medium 3, that are in direct contact with the ring-shaped element and that point radially outwards from the ring-shaped element in transverse directions x, y. The stiffening means 6 can have any number of spoke-like elements, i . e . more or less than six spoke-likeP2025, 0112 WO N February 5, 2026
[0156] 30
[0157] elements . Furthermore, the spoke-like elements can be arranged in a rotationally symmetric manner around the longitudinal direction z, as shown in figure 14, or they can be arranged in a rotationally asymmetric manner around the longitudinal direction z, e . g. for shaping the acoustic signal S during operation.
[0158] Compared to the acoustic transducer assembly 1 described in connection with figure 1, the medium 3 of the acoustic transducer assemblies 1 according to the exemplary embodiments in figures 16, 17 and 18 has a complex shape . In the case of a complex shaped and / or non-planar medium 3, the main extension plane 33 of the medium 3 corresponds to a tangential plane of a surface of the medium 3, on which the acoustic transducer 2 is arranged, for example .
[0159] In particular, the medium 3 shown in figure 16 has a round or curved shape . Further, a thickness D of the medium 3 is not constant . By contrast, the medium 3 shown in figure 17 has a pot-like shape with angled sidewalls . The medium 3 shown in figure 18 has a complex shape with flat portions as well as curved portions that have different thicknesses .
[0160] Figure 19 shows an exploded view of an acoustic transducer assembly 1 according to an exemplary embodiment, comprising a medium 3, a stiffening means 6, a coupling means 8, and an acoustic transducer 2. The medium 3 is complex shaped. The stiffening means 6 is a metal ring with a through hole that is arranged on the main extension plane 33 of the medium 3. Inside the through hole the coupling means 8 and the acoustic transducer 2 are arranged, such that the coupling means 8 is located between the acoustic transducer 2 and the medium 3. The stiffening means 6 is further configured as a fasteningP2025, 0112 WO N February 5, 2026
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[0162] means 7. In particular, the metal ring mechanically fixes the coupling element 8 and the acoustic transducer 2 on the medium 3 .
[0163] Figure 20 schematically shows a method for operating an acoustic transducer assembly 1. In particular, the acoustic transducer assembly 1 corresponds to the exemplary embodiment described in connection with figure 1, although the method works with any acoustic transducer assembly 1 described herein. During operation, an electric signal is applied to the acoustic transducer 2 such that the acoustic transducer 2 vibrates at a resonating mode, thereby emitting an acoustic signal S, for example an acoustic wave in the ultrasound spectral range . The acoustic signal S is emitted in the longitudinal direction z and is at least partially transmitted through the medium 3 that is e . g. sheet-like and mainly extends in transverse directions x, y. The acoustic signal S is coupled out of the acoustic transducer assembly 1 via a surface of the medium 3 facing away from the acoustic transducer 2 . Alternatively or in addition, the acoustic transducer 2 excites vibrational modes of the medium 3 during operation, such that the medium 3 acts as an active part of the acoustic transducer assembly 1 and a t least partially generates the acoustic signal S that is coupled out of the acoustic transducer assembly 1.
[0164] The acoustic signal S further propagates in air or a fluid outside of the acoustic transducer assembly 1, is at least partially back reflected by a target T, e . g. by an external obj ect, and is subsequently coupled back into the acoustic transducer assembly 1 via the surface of the medium 3 that is facing away from the acoustic transducer 2 . The back reflected acoustic signal S is transmitted through the mediumP2025, 0112 WO N February 5, 2026
[0165] 32
[0166] 3 before being detected by the acoustic transducer 2 and converted into an electric signal . In particular, the acoustic transducer 2 is hidden inside the acoustic transducer assembly 1 behind the medium 3, while probing the target T outside the acoustic transducer assembly 1 during operation. For example, the acoustic transducer assembly 1 can be used to obtain different types of information from the target T, such as a target distance, a surface type of the target T, and / or a target speed. The acoustic transducer assembly 1 can also be used for cliff detection, for example .
[0167] Furthermore, as shown in Figure 36, more than one acoustic transducer 2 can be operated simultaneously. For example, one acoustic transducer 2 is transmitting only, while a further acoustic transducer 21 is receiving only. For example, such an operation allows for an improved close distance behavior and or for a triangulation of the target T position. The seamless acoustic transducer assembly 1 described herein can achieve comparable detection capabilities than an exposed acoustic transducer 2, that has no medium 3 arranged on the out-coupling surface the acoustic transducer 2.
[0168] Figure 21 shows a schematic perspective view of the acoustic transducer assembly 1 described in connection with figure 4.
[0169] Figure 22 shows a schematic perspective view of an acoustic transducer assembly 1 according to an exemplary embodiment, wherein the medium 3 comprises a recess 31, e . g. in the main extension plane 33 of the medium 3. Inside the recess 31 an annular stiffening means 6 is arranged, that is elongated in the y direction. In other words, the stiffening means 6 is not rotationally symmetric around the longitudinal axis z . Inside the annulus of the stiffening means 6 the acousticP2025, 0112 WO N February 5, 2026
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[0171] transducer 2 is arranged. Further, the stiffening means 6 can be configured as a fastening means 7 for mechanically fixing the acoustic transducer 2 on the medium 3.
[0172] The shape of the stiffening means 6 is configured for shaping and / or guiding the transmitted and / or received acoustic signal S . The long axis of the stiffening means 6 can be aligned with an axis of the acoustic transducer 2.
[0173] Alternatively or in addition, the stiffening means 6 can be configured for adjusting and / or optimizing the position of the neutral point, neutral line and / or neutral area within the acoustic transducer assembly 1.
[0174] Compared to the acoustic transducer assembly 1 described in connection with figure 22, the stiffening means 6 of the acoustic transducer assembly 1 according to the exemplary embodiment in figure 23 is rotationally symmetric around the longitudinal axis z, i . e . it has the shape of a circular ring. A gap is arranged between the stiffening means 6 and side walls of the recess 31, such that the stiffening means 6 is in contact with the medium 3 only via a bottom surface of the recess 31 .
[0175] Compared to the acoustic transducer assembly 1 described in connection with figure 23, the stiffening means 6 of the acoustic transducer assembly 1 according to the exemplary embodiment in figure 24 is in contact with side walls of the recess 31. In particular, there is no gap between the stiffening means 6 and the medium 3 in transverse directions x, y.
[0176] Figure 25 shows a schematic cross-section of an acoustic transducer assembly 1 according to an exemplary embodiment,P2025, 0112 WO N February 5, 2026
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[0178] wherein a coupling means 8 is arranged between the acoustic transducer 2 and the medium 3. The coupling means 8 is configured for increasing an acoustic and / or mechanical coupling between the acoustic transducer 2 and the medium 3. Further, the coupling means 8 can be configured as a fastening means 7 for mechanically fixing the acoustic transducer 2 on the medium 3. For example, the coupling means 8 is a glue layer, a fiber reinforced glue layer, a matching layer, or an acoustic gel, as shown in the plan views of the coupling means 8 in the right panel of figure 24.
[0179] Figure 26 shows a pot-shaped carrier structure 4 of an acoustic transducer assembly 1 according to an exemplary embodiment . The pot-shaped carrier structure 4 has a circular cross-section in plan view of the main extension plane 33 of the medium 3 (not shown) . The acoustic transducer 2 is arranged at the bottom of the carrier structure 4. The cross section of the pot-shaped carrier structure 4 has a smaller diameter at the bottom, where the acoustic transducer 2 is arranged, than at the top, i . e . at a side opposite to the bottom.
[0180] Figures 27 and 28 show simulation results of a deformation of the medium 3 during operation of acoustic transducer assemblies 1 according to different exemplary embodiments . The acoustic transducer assembly 1 in Figure 27 consists of the acoustic transducer 2 arranged on the medium 3 that mainly extends in transverse directions x, y. The acoustic signal S (not shown, c . f . Fig. 20) is emitted primarily in the longitudinal direction z during operation. Figures 27 and 28 show a perspective view of the outside 0 (c . f . Fig. 1 ) of the acoustic transducer assembly 1, i . e . the main surface of the medium 3 that is shown in figures 27 and 28 faces awayP2025, 0112 WO N February 5, 2026
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[0182] from the acoustic transducer 2 . Compared to the acoustic transducer assembly shown in Figure 27, the acoustic transducer assembly 1 shown in Figure 28 further comprises an axially symmetric, i . e . ring shaped stiffening means 6 that is arranged on the medium 3 and encloses the acoustic transducer 2. Figures 27 and 28 show that the stiffening means 6 limits the deformation or vibration of the medium 3 to the immediate vicinity of the acoustic transducer 2.
[0183] Further an amplitude of the deformation of the medium 3 at the position of the acoustic transducer 2 is approximately doubled by means of the stiffening element 6, as shown in Figure 28, thereby also approximately doubling an amplitude of the acoustic signal S .
[0184] Figures 29 to 35 show plan views of the main extension plane 33 of the medium 3, i . e . the xy-plane, of acoustic transducer assemblies 1 according to different exemplary embodiments . In all of these exemplary embodiments a stiffening means 6 is arranged on and / or inside the medium 3 in the vicinity of the acoustic transducer 2. The stiffening means 6 shown in Figure 29 comprises two arc-shaped elements that are arranged on opposite sides of the acoustic transducer 2. The stiffening means 6 shown in Figure 30 comprises four arc-shaped elements that are arranged symmetrically around the acoustic transducer 2. The stiffening means 6 shown in Figure 31 comprises three spoke-like elements that are arranged symmetrically around the acoustic transducer 2 and that point radially outward from the acoustic transducer 2. The stiffening means 6 shown in Figure 32 comprises four arcshaped elements that are arranged symmetrically around the acoustic transducer 2, similar to the stiffening means 6 shown in Figure 30, and further comprises a ring-shaped element that is arranged concentrically with the acousticP2025, 0112 WO N February 5, 2026
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[0186] transducer 2 and that connects the four arc-shaped elements . The stiffening means shown in Figures 29 to 32 are arranged in an axially symmetric manner around the acoustic transducer 2 and are not configured for adjusting a non-centrosymmetric orientation, preferred direction and / or propagation direction of the acoustic signal S during operation.
[0187] The stiffening means 6 shown in Figure 33 comprises a single, semi-circular arc-shaped element that is arranged on one side of the acoustic transducer 2 in an axially asymmetric manner . Compared to the stiffening means shown in Figure 33, the stiffening means 6 shown in Figure 34 further comprises a ring-shaped element that is arranged concentrically with the acoustic transducer 2 and a further arc-shaped element that is arranged opposite to the semi-circular arc-shaped element . The stiffening means 6 shown in Figure 35 comprises a single, bar shaped element that is arranged on one side of the acoustic transducer 2. The stiffening means shown in Figures 33 to 35 are arranged in an axially asymmetric manner around the acoustic transducer 2 and are configured for adjusting a non-centrosymmetric orientation, preferred direction and / or propagation direction of the acoustic signal S during operation .
[0188] The invention is not restricted to the exemplary embodiments by the description on the basis of said exemplary embodiments . Rather, the invention encompasses any new feature and also any combination of features, which in particular comprises any combination of features in the patent claims and any combination of features in the exemplary embodiments, even if this feature or this combination itself is not explicitly specified in the patent claims or exemplary embodiments .P2025, 0112 WO N February 5, 2026
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[0190] Reference signs
[0191] 1 acoustic transducer assembly 2 acoustic transducer
[0192] 21 further acoustic transducer 3 medium
[0193] 31 recess
[0194] 32 surface structure
[0195] 33 main extension plane
[0196] 4 carrier structure
[0197] 41 recess
[0198] 5 electronic circuit
[0199] 51 sealing
[0200] 6 stiffening means
[0201] 7 fastening means
[0202] 8 coupling means
[0203] 9 potting material
[0204] D thickness
[0205] I inside
[0206] 0 outside
[0207] S acoustic signal
[0208] T target
[0209] x, y transverse directions
[0210] z longitudinal direction
Claims
P2025, 0112 WO N February 5, 202638Claims1. An acoustic transducer assembly ( 1 ) comprising an acoustic transducer (2 ) arranged on a medium (3) , such that an acoustic signal (S) is at least partially transmitted through the medium (3) by the acoustic transducer (2 ) and / or received through the medium (3) by the acoustic transducer (2 ) during operation .
2. The acoustic transducer assembly ( 1 ) according to claim 1, wherein the acoustic transducer (2 ) comprises an electromagnetic transducer, an electro-strictive transducer, a piezoelectric transducer, and / or a capacitive transducer .
3. The acoustic transducer assembly ( 1 ) according to claim 2, wherein the piezoelectric transducer comprises a ceramic element, a polymeric element, a composite element, and / or a thin-film element .
4. The acoustic transducer assembly ( 1 ) according to any of claims 1 to 3, wherein the acoustic transducer (2 ) is arranged on a carrier structure (4 ) .
5. The acoustic transducer assembly ( 1 ) according to claim 4, wherein the carrier structure (4 ) is pot-shaped.
6. The acoustic transducer assembly ( 1 ) according to any of claims 1 to 5, further comprising an electronic circuit (5) for operating the acoustic transducer (2 ) .
7. The acoustic transducer assembly ( 1 ) according to claims 5 and 6, wherein the acoustic transducer (2 ) and the electronicP2025, 0112 WO N February 5, 202639circuit (5) are arranged inside the pot-shaped carrier structure ( 4 ) .
8. The acoustic transducer assembly ( 1 ) according to any of claims 1 to 7, further comprising at least one further acoustic transducer (21 ) that is arranged on the medium (3) .
9. The acoustic transducer assembly ( 1 ) according to any of claims 1 to 8, wherein the medium (3) seals the acoustic transducer ( 2 ) .
10. The acoustic transducer assembly ( 1 ) according to any of claims 1 to 9, wherein the medium (3) forms an enclosure that hermetically seals the acoustic transducer (2 ) .
11. The acoustic transducer assembly ( 1 ) according to any of claims 1 to 10, wherein the medium (3) is shaped for guiding acoustic signals (S) to and / or from the acoustic transducer (2 ) .
12. The acoustic transducer assembly ( 1 ) according to any of claims 1 to 11, wherein a neutral point, a neutral line and / or a neutral area that is not deformed during operation is located inside the medium (3) , inside the acoustic transducer (2 ) , or between the medium (3) and the acoustic transducer ( 2 ) .
13. The acoustic transducer assembly ( 1 ) according to the previous claim, wherein the medium (3) is shaped for adjusting a location of the neutral point, neutral line, and or neutral area .P2025 , 0112 WO N February 5 , 20264014 . The acoustic transducer assembly ( 1 ) according to any of claims 1 to 13 , wherein the medium ( 3 ) comprises a recess ( 31 ) and the acoustic transducer ( 2 ) is arranged in the recess ( 31 ) .15 . The acoustic transducer assembly ( 1 ) according to any of claims 1 to 14 , further comprising a sti f fening means ( 6 ) .16 . The acoustic transducer assembly ( 1 ) according to claim 15 , wherein the sti f fening means ( 6 ) has a higher characteristic speci fic acoustic impedance than the medium ( 3 ) .17 . The acoustic transducer assembly ( 1 ) according to claims 15 or 16 , wherein the sti f fening means ( 6 ) is arranged inside the medium ( 3 ) , the sti f fening means ( 6 ) is arranged between the medium ( 3 ) and the acoustic transducer ( 2 ) and / or the sti f fening means ( 6 ) is part of the acoustic transducer ( 2 ) .18 . The acoustic transducer assembly ( 1 ) according to claims 15 to 17 , wherein the sti f fening means ( 6 ) is configured for changing a propagation direction of the acoustic signal ( S ) during operation .19 . The acoustic transducer assembly ( 1 ) according to any of claims 1 to 18 , further comprising a fastening means ( 7 ) configured for mounting the acoustic transducer ( 2 ) on the medium .20 . The acoustic transducer assembly ( 1 ) according to any of claims 1 to 19 , further comprising a coupling means ( 8 ) arranged between the medium ( 3 ) and the acoustic transducerP2025, 0112 WO N February 5, 2026- 41 -21. The acoustic transducer assembly ( 1 ) according to claim 20, wherein the coupling means ( 8 ) is configured for increasing an acoustic coupling between the acoustic transducer (2 ) and the medium (3) .
22. The acoustic transducer assembly ( 1 ) according to any of claims 1 to 21, wherein the acoustic transducer (2 ) is encapsulated with a potting material ( 9) that covers all surfaces of the acoustic transducer (2 ) that are not covered by the medium (3) .
23. The acoustic transducer assembly ( 1 ) according to any of claims 15 to 22, wherein the stiffening means ( 6) is configured as fastening means (7 ) and / or coupling means ( 8 ) , or vice versa .
24. A method for producing an acoustic transducer assembly ( 1 ) , comprising the steps of :- preparing a portion of a surface of a medium (3) for arranging an acoustic transducer (2 ) thereon,- arranging the acoustic transducer (2 ) on the portion of the surface of the medium (3) .
25. The method according to claim 24, wherein the step of preparing a portion of a surface of the medium (3) comprises arranging a stiffening means ( 6) on and / or in the medium (3) .
26. The method according to any of claims 24 or 25, comprising a further step of encapsulating the acoustic transducer (2 ) after arranging it on the medium (3) .P2025, 0112 WO N February 5, 20264227. A method of operating an acoustic transducer assembly ( 1 ) according to any of claims 1 to 23, comprising the steps of : - at least partially transmitting an acoustic signal (S) through the medium (3) by applying an electric signal to the acoustic transducer (2 ) ,- detecting by means of the acoustic transducer assembly ( 1 ) at least a part of the transmitted acoustic signal (S) that is back-reflected by a target (T) on a side of the medium (3) facing away from the acoustic transducer (2 ) .