Abstract: An effective bandwidth in a membrane based ultrasonic transducer is improved by a control element (C). The control element (C) is disposed on a first side (10a) of a first membrane (10) of the transducer to increase or decrease a displacement amplitude of the first membrane (10) towards the first side (10a) and/or the opposite, second side (10b). This induces a displacement asymmetry (Za< >Zb) in a motion of the first membrane (10) during a first vibration (V1) of the first membrane (10) to the first side (10a) compared to the second side (10b). The displacement asymmetry may result in improved bandwidth.

Abstract: A metrology apparatus for determining one or more parameters of a structure fabricated in or on a semiconductor substrate. The apparatus comprises a transducer array comprising a plurality of transducers positioned in a plane. The plurality of transducers comprises at least one transmitter transducer for emitting acoustic radiation in a frequency range from 1 GHz to 100 GHz towards the structure, and at least one receiver transducer for receiving acoustic radiation reflected and/or diffracted from the structure.

Abstract: An acoustic microscope system is described that includes a container for holding a medium with an object to be measured. Compressional waves are generated by a probe into the medium. The compressional waves travel along an acoustic axis to interact with the object. Shear waves are generated by a shear wave source into the medium. The shear waves travel along a secondary axis which intersects with the acoustic axis at the object with a non-zero angle. The shear waves are configured to cause shear wave oscillations directed transverse to the secondary axis and at least partially directed along the acoustic axis. A measurement of the object is determined based on the compressional waves having interacted with the object as a function of the generation of the shear waves.

Abstract: An ultrasonic transducer is described that includes a stack of at least two membranes attached to a substrate. An electric circuit is coupled to the electrodes with a controller configured to apply a first electric signal to a first electrode on the first membrane, and a different, second electric signal to a second electrode on the second membrane. The first and second electric signals are configured to apply a varying voltage between the first electrode and the second electrode during a respective vibration cycle of the membranes. The first electrode on the first membrane is configured to interact with the second electrode on the second membrane by a varying electrostatic force during the respective vibration cycle depending on the varying voltage.

Abstract: A method and system for controlling an array of piezoelectric transducers (11, 12, 13). Respective driving signals (Vn) are applied to the transducers. The driving signals (Vn) comprise an alternating component (A) oscillating at one or more driving frequencies to cause corresponding vibrations in the transducers for generating acoustic waves (Wn). One or more of the driving signals (Vn) are offset by a respective bias voltage (Bn). The bias voltage (Bn) is controlled to reduce a difference in resonance frequencies between the transducers. To eliminate any remaining difference, the alternating component (A) to at least a subset of the transducers (11,12) is periodically reset. In this way the phases of the resulting acoustic waves (W1,W2) can be synchronized.

Abstract: A communication system (1) comprising a first and a second underwater wearable device to be worn by a swimmer at mutually distant locations is disclosed herein. The communication system is configured to derive information pertaining to the swimmer from properties of a version of the acoustic signal transmitted from a first communication module of the first underwater wearable device to a second communication module of the second underwater wearable device.

Abstract: The present document relates to a heterodyne scanning probe microscopy (SPM) method for subsurface imaging, and includes: applying an acoustic input signal to a sample and sensing an acoustic output signal using a probe. The acoustic input signal comprises a plurality of signal components at unique frequencies, including a carrier frequency and at least two excitation frequencies. The carrier frequency and the excitation frequencies form a group of frequencies, which are distributed with an equal difference frequency between each two subsequent frequencies of the group. The difference frequency is below a sensitivity threshold frequency of the cantilever for enabling sensing of the acoustic output signal. The document also describes an SPM system.

Abstract: A piezoelectric device and method of manufacturing are described. A first substrate is provided with an array of pillars comprising piezoelectric material. A second substrate is provided with a piezoelectric layer facing respective ends of the pillars. The respective ends of the pillars are pushed into the piezoelectric layer, while the piezoelectric layer is at least partially liquid. The piezoelectric layer is solidified to form an integral connection between the piezoelectric layer and the pillars. The piezoelectric layer can thus form a bridging structure between the respective ends of the pillars. The integral piezoelectric structure can be poled by high voltage. The bridging structure can act as a platform for depositing electrical contacts. The piezoelectric device can be used for generating or detecting acoustic waves, e.g. in medical imaging.

Abstract: The photonic integrated device comprises a substrate, a plurality of mechanical resonator structures on a surface of the substrate, exposed to receive sound waves from outside the device; a plurality of sensing optical waveguides, each sensing optical waveguide at least partly mechanically coupled to at least one of the mechanical resonator structures, or a sensing optical waveguide that is at least partly mechanically coupled to all of the mechanical resonator structures; an input optical waveguide on the surface of the substrate, coupled to the plurality of sensing optical waveguides or the single sensing optical waveguide, for supplying light to the plurality of sensing optical waveguides or the single sensing optical waveguide; at least one output optical waveguide on the surface of the substrate, coupled to the plurality of sensing optical waveguides or the single sensing optical waveguide, for collecting light from the plurality of sensing optical waveguides or the single sensing optical waveguide that

Abstract: The photonic integrated device for converting a light signal into sound comprises-a substrate having a substrate surface, an optical waveguide on the substrate surface, a photo-acoustic conversion body, comprising at least one volume of fractionally light absorbing material or formed entirely of fractionally light absorbing material, wherein a width of the photo-acoustic conversion body is greater than a width of the optical waveguide and means for enhancing distribution of light from the optical waveguide over the photo-acoustic conversion body.

Abstract: The sound detection device comprises a substrate, an array of sound detectors in or on a surface of the substrate, a processing circuit coupled to the sound detectors, the processing circuit being configured to sum signals from the sound detectors with relative time delays or phase shifts that compensate for propagation delay of sound along the array in a sound propagation mode that is bound to said surface. In an embodiment the sound in said sound propagation mode is bound to the surface using an acoustic waveguide, wherein the surface of the substrate forms a part of the acoustic waveguide, the sound detection device comprising a wall facing the array of sound detectors, with a space between the surface of the substrate and the wall, the sound detection device comprising an opening that provides incoming sound from outside the device access to said space, for excitation of the wave in the bound propagation mode in the acoustic waveguide by sound from outside the device.

Abstract: The photo-acoustic conversion based sound emitter device has a sound output surface for transmitting sound wave vibrations to a medium outside the device. An optical waveguide, is used to transmit light through an optical path within the device. First and second photo-acoustic conversion volumes, at different distances from the sound output surface, are used for transmitting sound generated in the first and second volume to the medium via the sound output surface, the optical path extending directly or indirectly successively through the first and second photo-acoustic conversion volume.

Abstract: A method and system for controlling an array of piezoelectric transducers (11, 12, 13). Respective driving signals (Vn) are applied to the transducers. The driving signals (Vn) comprise an alternating component (A) oscillating at one or more driving frequencies to cause corresponding vibrations in the transducers for generating acoustic waves (Wn). One or more of the driving signals (Vn) are offset by a respective bias voltage (Bn). The bias voltage (Bn) is controlled to reduce a difference in resonance frequencies between the transducers. To eliminate any remaining difference, the alternating component (A) to at least a subset of the transducers (11,12) is periodically reset. In this way the phases of the resulting acoustic waves (W1,W2) can be synchronized.

Abstract: An acoustic device (100) comprises an array of acoustic membranes (1, 2, 3, 4) formed on a foil (10). Each of the acoustic membranes (1, 2, 3, 4) is configured to vibrate ata resonance frequency (Fr) of the acoustic membranes (1, 2, 3, 4) for generating respective acoustic waves (W1,W2,W3,W4). Relative phases (??12,??34) are determined at which the acoustic membranes (1, 2, 4, 5) are actuated for generating a predetermined interference pattern (C) between the acoustic waves (W1,W2,W3,W4). A lamb wavelength (As) is determined of lamb waves (Ws) at the resonance frequency (Fr) travelling through intermediate sections (lOi, lOj) of the foil between adjacent acoustic membranes (1,2; 3,4).

Abstract: A method and system for performing subsurface atomic force microscopy measurements, the system comprising: a signal source for generating an drive signal; a transducer configured to receive the drive signal for converting the drive signal into vibrational waves and coupling said vibrational waves into a stack comprising a sample for interaction with subsurface features within said sample; cantilever tip for contacting the sample for measuring surface displacement resulting from the vibrational waves to determine subsurface features; wherein the system includes a measurement device for measuring a measurement signal returning from the transducer during and/or in between the subsurface atomic force microscopy measurements.

Abstract: An ultrasound sub-surface probe microscopy device (1) is provided comprising a stage (10), a signal generator (20), a scanning head (30), a signal processor (50) and a scanning mechanism (16). In use, the stage (10) carries a sample (11) and the scanning M mechanism (16) provides for a relative displacement between the sample (11) and the scanning head (30), along the surface of the sample. The scanning head (30) comprises an actuator (31) configured to generate in response to a drive signal (Sdr) from the signal generator (20) an ultrasound acoustic input signal (Iac). The generated ultrasound acoustic input signal (Iac) has at least one acoustic input signal component (Iac1) with a first angular frequency (?1). The scanning head (30) further comprises a tip (32) to transmit the acoustic input signal (Iac) through a tip-sample interface (12) as an acoustic wave (Wac) into the sample.

Abstract: The present document relates to a heterodyne scanning probe microscopy (SPM) method for subsurface imaging, and includes: applying an acoustic input signal to a sample and sensing an acoustic output signal using a probe. The acoustic input signal comprises a plurality of signal components at unique frequencies, including a carrier frequency and at least two excitation frequencies. The carrier frequency and the excitation frequencies form a group of frequencies, which are distributed with an equal difference frequency between each two subsequent frequencies of the group. The difference frequency is below a sensitivity threshold frequency of the cantilever for enabling sensing of the acoustic output signal. The document also describes an SPM system.

Abstract: The present document relates to a heterodyne scanning probe microscopy (SPM) method for subsurface imaging, and includes: applying, using a transducer, an acoustic input signal to the sample, wherein the acoustic input signal has a frequency of at least 1 gigahertz; sensing an acoustic output signal using a probe, the probe including a cantilever and a probe tip, wherein the probe tip is in contact with the surface, wherein the acoustic output signal is representative of acoustic waves responsive to the acoustic input signal that are measurable at the surface; wherein the acoustic input signal is applied to the sample comprising a distinct pulse of acoustic energy followed by a relaxation period, wherein an acoustic power of the acoustic input signal during the pulse is at least twice as large as an acoustic power during the relaxation period. The present document further relates to a scanning probe microscopy method.

Abstract: An acoustic device (100) comprises an array of acoustic transducers (10a,10b) formed by a patterned stack (12-15) on a flexible substrate (11). The stack comprises a piezoelectric layer (13) sandwiched between respective bottom and top electrode layers (12,15), and a patterned insulation layer (14) formed by a pattern of insulation material (14m). The pattern comprises insulated areas (A14) where the insulation material (14m) is disposed between one of the electrodes (12,15) and the piezoelectric layer (13), and contact areas (A10) without the insulation material (14m) where both electrodes (12,15) contact the piezoelectric layer (13).

Abstract: A device (100) and method for adhering by suction to a target surface (200). The device has a substrate (20) with a contact surface (20a) for contacting the device (100) to the target surface (200). A plurality of pocket (10) are formed by respective pocket surfaces (10a) concavely extending into the contact surface (20a). The pockets (10) have an open side (10b) facing and being closed off by the target surface (200). A flexible membrane (15) forms at least part of the pocket surface (10a). An actuator (40) is configured to actuate the flexible membrane (15). A one-way valve (30) through the pocket surface (10a) is configured to direct a contents of the pocket (10) via the one-way valve (30) to an environment (300).