Resolution of Image Compounding with a Ring Array Transducer

Rigid Resolution of a Finitely Generated Module Over a Regular Local Ring

A Flexible Ultrasound Transducer Array with Micro-Machined Bulk PZT

This paper proposes a novel flexible piezoelectric micro-machined ultrasound transducer, which is based on PZT and a polyimide substrate. The transducer is made on the polyimide substrate and packaged with medical polydimethylsiloxane. Instead of etching the PZT ceramic, this paper proposes a method of putting diced PZT blocks into holes on the polyimide which are pre-etched. The device works i...

Photoacoustic and ultrasonic coimage with a linear transducer array.

A technique is developed to simultaneously acquire ultrasound and photoacoustic (PA) images based on a linear transducer array. The system uses conventional ultrasound for rapid identification of potential targets. After a target is identified, the ultrasound echo and PA signals can be simultaneously obtained with optimized excitation and a signal collection sequence. The corresponding ultrasou...

Acoustic resolution photoacoustic Doppler flowmetry using a transducer array: optimising processing for velocity contrast

This work demonstrates the first measurements of blood flow velocity using photoacoustic flowmetry (PAF) employing a transducer array. The measurements were made in a flow phantom consisting of a tube (580 μm inner diameter) containing blood flowing steadily at physiological speeds ranging from 3 mm/s to 25 mm/s. Velocity measurements were based on the generation of two successive photoacoustic...

Enhancement of photoacoustic tomography by ultrasonic computed tomography based on optical excitation of elements of a full-ring transducer array.

Photoacoustic computed tomography (PACT) is a hybrid technique that combines optical excitation and ultrasonic detection to provide high-resolution images in deep tissues. In the image reconstruction, a constant speed of sound (SOS) is normally assumed. This assumption, however, is often not strictly satisfied in deep tissue imaging, due to acoustic heterogeneities within the object and between...