| Literature DB >> 17375836 |
Qifa Zhou1, Xiaochen Xu, Emanuel J Gottlieb, Lei Sun, Jonathan M Cannata, Hossein Ameri, Mark S Humayun, Pengdi Han, K Kirk Shung.
Abstract
High-frequency needle ultrasound transducers with an aperture size of 0.4 mm were fabricated using lead magnesium niobate-lead titanate (PMN-33% PT) as the active piezoelectric material. The active element was bonded to a conductive silver particle matching layer and a conductive epoxy backing through direct contact curing. An outer matching layer of parylene was formed by vapor deposition. The active element was housed within a polyimide tube and a 20-gauge needle housing. The magnitude and phase of the electrical impedance of the transducer were 47 omega and -38 degrees, respectively. The measured center frequency and -6 dB fractional bandwidth of the PMN-PT needle transducer were 44 MHz and 45%, respectively. The two-way insertion loss was approximately 15 dB. In vivo high-frequency, pulsed-wave Doppler patterns of blood flow in the posterior portion and in vitro ultrasonic backscatter microscope (UBM) images of the rabbit eye were obtained with the 44-MHz needle transducer.Entities:
Mesh：
Year: 2007 PMID： 17375836 DOI： 10.1109/tuffc.2007.290
Source DB: PubMed Journal: IEEE Trans Ultrason Ferroelectr Freq Control ISSN： 0885-3010 Impact factor: 2.725