DEVELOPMENT OF VHF TRANSDUCERS & ARRAYS

临床应用于皮肤科、眼科和 血管内成像、高性能单元件换能器和 必须开发线性阵列。由于压电式元件 在这些设备中使用的很小，它们不能用 传统的压电材料和方法。在这个项目中， 频率范围内的单元件换能器和线阵 30至80 MHz将开发并使用超声波进行测试 背向散射显微镜和柔性波束形成系统， 正在与该项目并行开发。单个元素 使用改进的PT制作了从20到90 MHz的换能器， 细晶PZT、1-3纤维复合材料及PZN-PT及其性能 评估过了。设计了一种基于细晶PZT的30 MHz 48元线阵. 正在开发中。初步结果显示，带宽优于45% 以及相邻元件之间的串扰小于-28分贝。 元素对元素的均匀性优于20%。这些设备将 用于对切除的动物组织和患者进行成像 一旦UBM系统和BEAM成形器得到临床医生的帮助 是完全显影的，并与 传统设备。

For clinical applications in dermatology, ophthalmology and intravascular imaging, high performance single element transducer and linear arrays have to be developed. Since the piezoelectric elements used in these devices are small, they cannot be fabricated with conventional piezoelectric materials and methods. In this project, single element transducers and linear arrays in the frequency range from 30 to 80 MHz will be developed and tested using an ultrasonic backscatter microscope and a flexible beam forming system which are being developed in parallel with this project. Single element transducers ranging from 20 to 90 MHz have made using modified PT, fine grain PZT, 1-3 fiber composite and PZN-PT and performance assessed. A 48 element linear array at 30 MHz using fine grain PZT is being developed. Initial results show a bandwidth of better than 45% and a cross-talk between adjacent elements of less than -28 dB. Element to element uniformity is better than 20%. These devices will be used to image excised animal tissues and patients with the assistance from the clinicians once the UBM system and the beam former are completely developed and compared to the images obtained by conventional devices.