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: 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: An X-ray imaging device with an X-ray conversion area on a flexible circuit such as a Thin Film Transistor circuit with an array of detector cells is manufactured in a method comprising the steps of — providing a flexible carrier layer on a substrate plate, with a first surface of the flexible carrier layer attached to the substrate plate and a second surface of the flexible carrier layer exposed, whereby the substrate plate hinders the flexible carrier layer from bending; — creating an array of detector cells on a part of the second surface; — mounting a peripheral circuit on the second surface outside said part, interconnected to the array of detector cells; — attaching a further layer to the second surface, after or before mounting the peripheral circuit, the further layer comprising an X-ray conversion area at least over the array of detector cells, the further layer being attached to the flexible carrier layer beyond a first edge of the array of detector cells, and beyond the peripheral circuit, the furt

Abstract: A foldable thin film device assembly is provided comprising: a flexible thin film device with a thickness smaller than 50 micrometer. The thin film device has a stack of electroactive layers formed on a substrate. A protective inorganic capping layer caps the stack of electroactive layers and a backside elastomeric layer backs the flexible thin film device. A frontside transparent elastomeric layer covers the flexible thin film device, and backside and frontside flexible layers are dimensioned to mechanically form a neutral line for the protective inorganic layer. The elastomeric material has a Young's modulus smaller than 100 MPa smaller than 100 MPa and thickness larger than 100 micron, with a flexural rigidity equal or larger than the thin film device.

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 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).

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 foldable thin film device assembly is provided comprising: a flexible thin film device with a thickness smaller than 50 micrometer. The thin film device has a stack of electroactive layers formed on a substrate. A protective inorganic capping layer caps the stack of electroactive layers and a backside elastomeric layer backs the flexible thin film device. A frontside transparent elastomeric layer covers the flexible thin film device, and backside and frontside flexible layers are dimensioned to mechanically form a neutral line for the protective inorganic layer. The elastomeric material has a Young's modulus smaller than 100 MPa smaller than 100 MPa and thickness larger than 100 micron, with a flexural rigidity equal or larger than the thin film device.

Abstract: A collimator filter (10) comprises an entry surface (11) to receive incident light (Li, Li?) at different angles of incidence (?i, ?i?) and an exit surface (12) to allow output light (Lo) to exit from the collimator filter (10). A filter structure between the entry surface (11) and the exit surface (12) transmits only parts of the incident light (Li) having angles of incidence (?i) below a threshold angle (?max). The filter structure comprises a patterned array of carbon nanotubes (1), wherein the nanotubes (1) are aligned extending in a principal transmission direction (Z) between the entry surface (11) and the exit surface (12). The nanotubes (1) are arranged to form a two dimensional pattern (P) transverse to the principal transmission direction (Z). Open areas of the pattern (P) without nanotubes (1) form micro-apertures (A) between the nanotubes (1) for transmitting the output light (Lo) through the filter structure.

Abstract: The element (50) comprises a first electrode (51), a self-assembled system (52), which is or comprises a monolayer an a second electrode (54). A polymeric contact layer (53) that has been deposited wet-chemically is present between the self-assembled system (52) and the second electrode (54). Suitably, both the self-assembled system (52) and the contact layer (53) are provided in a cavity (40).