Phononic crystals for suppressing crosstalk in ultrasonic flowmeters

Ultrasonic flowmeters that use transit-time ultrasonic transducers face measurement errors due to 'crosstalk,' whereby the working signal travels through the pipe wall and couplings, interfering with the signal from the fluid. Although various procedures have been proposed to solve the issue of crosstalk, they're limited to low-frequency...

Ultrasonically Powered and Controlled Microsystem for Dual-Wavelength Optogenetics with a Multi-Load Regulation Scheme

This letter presents an ultrasonically powered dual-wavelength optogenetic device that targets simultaneous excitation and inhibition of neural activities, or in a broader sense, optical stimulation in two distinct wavelengths for targeting different populations of neurons. This can be applied to a variety of neurological disorders. The...

Design and Proof-of-Concept of a Matrix Transducer Array for Clamp-on Ultrasonic Flow Measurements

Common clamp-on ultrasonic flow meters consist of two single-element transducers placed on the pipe wall. Flow speed is measured noninvasively, i.e., without interrupting the flow and without perforating the pipe wall, which also minimizes safety risks and avoids pressure drops inside the pipe. However, before metering, the transducers have...

Acoustic Modulation Enables Proton Detection with Nanodroplets at Body Temperature

Superheated nanodroplet (ND) vaporization by proton radiation was recently demonstrated, opening the door to ultrasound-based in vivo proton range verification. However, at body temperature and physiological pressures, perfluorobutane nanodroplets (PFB-NDs), which offer a good compromise between stability and radiation sensitivity, are not...

Simulation of ultrasonic beam propagation from phased arrays in anisotropic media using linearly phased multi-Gaussian beams

Phased array ultrasonic testing is widely used to test structures for flaws due to its ability to produce steered and focused beams. The inherent anisotropic nature of some materials, however, leads to skewing and distortion of the phased array beam and consequently measurement errors. To overcome this, a quantitative model of phased array...

Can sources and receivers be interchanged for imaging?

The design of ultrasound scanning systems for applications such as breast cancer detection is a challenging task, especially when the number of sources and receivers increases and they become spread over a large surface. In order to determine the number of transducers and above all their position, several approaches could be followed. A simple...