The present disclosure relates to circuitry for driving a load. The circuitry comprises driver circuitry configured to generate a drive signal, based on an input signal to the driver circuitry, for driving the load, and commutator circuitry for coupling the driver circuitry to the load. The commutator circuitry is configured to alternate between commutation states in response to a level of the drive signal meeting a drive signal threshold or in response to a level of the input signal meeting a first input signal threshold. The circuitry is configured to apply an offset to the input signal when the input signal is below a second input signal threshold so as to increase a minimum level of the drive signal above the drive signal threshold or to increase a minimum level of the input signal above the first input signal threshold.

A system for controlling damages in cleaning a semiconductor wafer comprising features of patterned structures, the system comprising: a wafer holder for temporary restraining a semiconductor wafer during a cleaning process; an inlet for delivering a cleaning liquid over a surface of the semiconductor wafer; a sonic generator configured to alternately operate at a first frequency and a first power level for a first predetermined period of time and at a second frequency and a second power level for a second predetermined period of time, to impart sonic energy to the cleaning liquid, the first predetermined period of time and the second predetermined period of time consecutively following one another; and a controller programmed to provide the cleaning parameters, wherein at least one of the cleaning parameters is determined such that a percentage of damaged features as a result of the imparting sonic energy is lower than a predetermined threshold.

A lithographic apparatus has a substrate holder configured to hold a substrate and a projection system configured to project a radiation beam onto the substrate held by the substrate holder. There is also a fluid handling system configured to confine immersion liquid to a space between a part of the projection system and a surface of the substrate so that the radiation beam can irradiate the surface of the substrate by passing through the immersion liquid. An excitation device is provided to generate surface acoustic waves in the substrate and propagating toward the immersion liquid.

Acoustophoretic devices are disclosed. The devices include a flow chamber, an ultrasonic transducer, a reflector, an inlet, a filtrate outlet, a concentrate outlet, and optionally a lipid collection trap. The ultrasonic transducer and reflector create a multi-dimensional acoustic standing wave in the flow chamber that traps and separates red blood cells and/or lipids from blood. Concentrated red blood cells can be recovered via the concentrate outlet, the lipids can be recovered via the lipid collection trap, and the remaining blood can be recovered via the filtrate outlet. Methods for separating blood components (e.g., red blood cells, lipids, platelets, white blood cells) from blood are also disclosed. The red blood cells can undergo washing with a solvent to remove undesired admixtures. Cryoprotectants can be added or removed from the blood.

Typically, the displacement of piezo-electric actuators is quite small. Accordingly, some sort of amplification may be needed for specific applications to amplify the displacement of the piezo-electric actuator, and thereby amplify the haptic feedback. For all solutions, the goal is to amplify the displacement of a moveable mass in order to increase vibration to improve the haptic feedback. If the host device is a wearable or portable device, e.g. a smart watch, it would be preferable to excite a heavy moveable mass that is already part of the assembly to harvest enough energy to transmit to the interface with the user. If the device is a large display, e.g. a display in a vehicle info system, the display itself could be the moveable mass.

A multilayer ultrasonic transducer of an embodiment includes: a plurality of stacked oscillators; external electrodes disposed on outer exposed surfaces of two oscillators disposed in the outermost layers out of the plurality of oscillators; and a plurality of internal electrodes each disposed between two of the plurality of oscillators. There are provided electrode regions in which the plurality of internal electrodes are arranged such that the number of layers of the internal electrodes in a direction in which the oscillators are stacked gradiently increases from an inner region toward an outer peripheral region of the plurality of oscillators, and ultrasonic waves emitted from the plurality of oscillators are focused toward at least the inner region.

Flextensional transducers and methods of using flextensional transducers. The transducer includes a piezoelectric element and may include at least one endcap coupled with the piezoelectric element. The endcap may have an outer portion formed of a first material and an inner portion formed of a second material having a greater flexibility than the first material. The endcap may be coupled with an annular piezoelectric element near either its outer circumference or its inner circumference. The piezoelectric element may be a planar disk or have a curved bowl-shape. The transducer may be coupled with, and at least partially restrained by, a support structure. The transducer may also be configured to permit light to pass therethrough.

This document describes techniques and apparatuses directed at localized haptic feedback in electronic devices using pressure-sensitive adhesive (PSA) and piezoelectric haptic actuators. In aspects, an electronic device includes a housing having a frame defining a slot. An actuator is adhered to the frame at the bottom of the slot by the PSA. When a force is applied to an exterior surface of the actuator (“button press”), the PSA compresses and an extending member attached to the actuator, opposite the exterior surface, slidably moves within an aperture in the frame at the bottom of the slot. The extending member engages a sensor module (e.g., piezoelectric sensor) and the electronic device registers a button press. The sensor module then applies haptic feedback to the extending member and through the actuator to the exterior surface. When the force is removed from the actuator's exterior surface, the PSA expands to an approximate original thickness.

Embodiments are provided that enhance ultrasound efficacy by for example, high efficiency, signal measurement, calibration, and assurance systems with a control system radio-frequency (RE) driver configured to drive one or more focused ultrasound transducers. The RE driver can comprise one or more power amplifiers including one or more III-V semiconductors, (e.g., gallium nitride GaN, GaAs, GaSb, InP, InAs, InSb, InGaAs, AlSb, AlGaAs, and/or AlGaN) field-effect transistors to efficiently provide high power with distinct narrow-band RE signals over a wide frequency range. The RE driver can include a power measurement and/or calibration system to monitor the amplitude and phase of the RE signal output from the power amplifier and estimate the amount of RE power delivered to the ultrasound transducers.

Provided is a vibration wave motor, including: a vibration body; a friction member; a press member configured to pressurize the vibration body against the friction member; a base member configured to fix the friction member; and a damping member configured to damp vibration, wherein the vibration body and the friction member are configured to move relative to each other, wherein the friction member includes: a first surface having a first region held in abutment against the vibration body; and a second surface, which is a back surface of the first surface, and has a second region held in abutment against the base member, wherein at least one of the first surface and the second surface has a third region held in contact with the damping member, and wherein positions of the first region and the third region in a pressurizing direction of the press member are different from each other.