An energy harvesting circuit is disclosed and comprises one or more electrical loads that consume direct current (DC) power, a rectifier, and a hybrid acoustic absorber. The rectifier comprises one or more active switching elements that are driven by a gate drive voltage. The hybrid acoustic absorber comprises a diaphragm and a voice coil. The diaphragm is constructed at least in part of a piezoelectric material. The piezoelectric material is configured to generate a diaphragm voltage in response to sound waves deforming the diaphragm. The diaphragm voltage is at least equal to the gate drive voltage to drive the one or more active switching elements of the rectifier. The voice coil is attached to the diaphragm and configured to generate a voice coil voltage that is less than the gate drive voltage of the one or more active switching elements.

A solid-state quantum memory includes a vibrator supported in a displaceable (vibratable) manner on a substrate and a vibration exciter configured to excite the vibrator to vibrate. A rare-earth element is introduced into the vibrator and the introduced rare-earth element forms an electronic two-level system in the vibrator. The vibrator is supported on the substrate by a support. The substrate including a piezoelectric element formed from a piezoelectric material, as well as a first electrode and a second electrode formed by sandwiching the piezoelectric element, serves as the vibration exciter.

In a reservoir element that has a plurality of vibrators, at least one of the plurality of vibrators has a vibration state that is different from the vibration states of the other vibrators. The vibrations of the plurality of vibrators are configured to affect each other.

A metal substrate supported by a wiring substrate includes a first extending portion and a first connection portion connected to the first extending portion. The first connection portion includes a first region facing a portion of a wiring substrate in a Z-axis direction, a second region being continuous from the first region, and a third region being continuous from the second region. When viewed in the Z-axis direction, in a direction perpendicular to a connection direction in which the third region is connected to the second region, a width of the second region is larger than a width of the third region. A first bonding member bonding the wiring substrate and the metal substrate includes a first portion disposed between the portion and the first region, and a second portion being continuous from the first portion. The second portion reaches the second region but does not reach the third region.

An actuator device includes a wiring substrate; a metal substrate; a first electrode unit provided to the metal substrate; a piezoelectric drive body disposed on the first electrode unit; a second electrode unit disposed on a first main surface of the piezoelectric drive body; a piezoelectric detection body disposed on the second electrode unit; a third electrode unit disposed on a third main surface of the piezoelectric detection body; a connection unit; an input unit; and an output unit. The connection unit is configured to be electrically connected to a reference potential on an outside such that a potential of the second electrode unit becomes the reference potential. The input unit is configured to input a drive signal to the first electrode unit from the outside. The output unit is configured to output an output signal generated in the piezoelectric detection body, to the outside from the third electrode unit.

A metal substrate supported by a wiring substrate includes a movable portion, a first extending portion, a first coupling portion that couples the first extending portion and the movable portion, and a first connection portion connected to the first extending portion. The first connection portion includes a first fixing region fixed to the wiring substrate, and a first connection region connected to the first extending portion and to the first fixing region. The first connection region includes a first bent portion. The first bent portion has a first outer edge on a movable portion side, and a second outer edge opposite the movable portion, and each of the first outer edge and the second outer edge is bent toward the movable portion side when viewed in a Z-axis direction.

This application relates to methods and apparatus for driving a transducer with switching drivers. A switching driver has first and second supply node for receiving supply voltages and includes an output bridge stage, a capacitor and a network of switches. The network of switches is operable in different switch states to provide different switching voltages to the output bridge stage. A controller is configured to control the switch state of the network of switches and a duty cycle of output switches of the output bridge stage based on an input signal to generate an output signal for driving the transducer.

Technologies for a microelectromechanical system (MEMS) made up of composable piezoelectric actuators is disclosed. An elongated piezoelectric rod is disposed between a top and a bottom electrode. The top electrode runs along one edge of the top of the piezoelectric rod for a first segment, then runs along the other edge of the top of the piezoelectric rod for the a second segment. When a voltage is applied across the electrodes, the piezoelectric rod bends in a first direction for the first segment and in a second direction opposite the first for the second segment, displacing the tip of the rod. Several such rods can be joined in parallel and/or series, allowing for large-scale systems to be composed.

A structure includes an oriented piezoelectric polymer arranged in a circular tubular or circular columnar shape, wherein the orientation angle of the piezoelectric polymer with respect to the central axis of the structure is 15° to 75°, the piezoelectric polymer includes a crystalline polymer having an absolute value of 0.1 to 1000 pC/N for the piezoelectric constant d14 when the orientation axis is the third axis, and the piezoelectric polymer includes a P-body containing a crystalline polymer with a positive piezoelectric constant d14 value and an N-body containing a crystalline polymer with a negative value, wherein for the portion of the central axis of the structure having a length of 1 cm, the value of T1/T2 is 0 to 0.8, T1 being the smaller and T2 being the larger of (ZP+SN) and (SP+ZN), where ZP, SP, ZN, and SN are particularly defined masses.

In this liquid ejecting head, the pressure chamber extends in a second direction crossing a first direction, the first direction being a direction from the pressure chamber to the nozzle. The pressure chamber and the absorbing chamber are disposed at a same position in the first direction and next to each other in the second direction. The actuator is disposed on an opposite side in the first direction with respect to the pressure chamber. The absorption member is disposed on the opposite side in the first direction with respect to the absorbing chamber, the absorption member including at least part of members constituting the actuator.