DEVELOPMENT OF VHF TRANSDUCERS & ARRAYS

用于皮肤科、眼科和 血管内成像，高性能单元件换能器， 必须开发线性阵列。 由于压电元件 这些设备中使用的是小的，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性阵列 从30到80兆赫将开发和测试使用超声波 背散射显微镜和柔性光束形成系统， 与此项目同时开发。 单个元件 使用改进的PT制造了20至90 MHz的换能器， 细晶PZT、1-3纤维复合材料和PZN-PT及其性能 评估。 使用细晶粒PZT在30 MHz处的48元件线性阵列是 正在开发中。 初步结果显示带宽优于45% 并且相邻元件之间的串扰小于-28dB。 元件间均匀性优于20%。 这些设备将 用于对切除的动物组织和患有 一旦UBM系统和波束形成器 完全显影并与通过以下方式获得的图像进行比较： 常规设备。

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.