Development of High Frequency Ultrasound Transducers

描述(由申请人提供)：利用 PZT/聚合物复合材料具有良好的压电性和声学性能 由于以下限制，未商业化使用20 MHz的频率 传统的骰子填充工艺。在拟议的工作中--磁带浇注 技术将被用来生产单元件换能器、年轮阵列、 以及共振频率从20 MHz到50 MHz的线性阵列。通过 使用印刷有逃逸相(例如碳)的PZT来限定开槽空间， 2-2复合材料可形成PZT束宽小于15微米和开口数 空间小于10微米。由这种复合材料制成的高频换能器 将表现出比现有高频更高的灵敏度和带宽 技术(单片式PZT板、氧化锌薄膜和PVDF薄膜)。这样的一种 Advance将极大地提高眼科超声的诊断能力， 多普勒血流测量、真皮和表皮成像和超声波 背向散射显微镜。在这方面需要调查的具体应用 程序是用于多普勒流的衍射光栅传感器，其中磁带播放 复合材料还有一个额外的优势，即一次性使用成本低； 测量角膜厚度的测厚仪.30至50 MHz单元件和 用于超声背向散射显微镜的环形阵列；和&gt；30 MHz线阵 数组。 建议的商业应用： 现有的商业应用包括用于多普勒的衍射光换能器 流量测量、角膜厚度测量用厚度计、超声波 背向散射显微镜，并改进了&gt；15 MHz线性和相控的图像质量 数组。用于驱动&gt；30 MHz的间接和波束成形技术的发展 线性阵列将在眼科成像、皮肤科成像和 关节成像。

DESCRIPTION (Provided by Applicant): Ultrasonic transducers that make use of the good piezoelectric and acoustic properties of PZT/polymer composites have not been commercialized for frequencies > 20 MHz due to the limitations of conventional dice-and-fill processing. In the proposed work tape-casting technology will be used to produce single element transducers, annuiar arrays, and linear arrays with resonance frequencies ranging from 20 to > 50MHz. By using PZT printed with a fugitive phase (such as carbon) to define kerf space, 2-2 composites can be formed with PZT beam widths less than 15 um and kerf space less than 10 um. High frequency transducers made from such composites will exhibit much higher sensitivity and bandwidth than existing high frequency technologies (monolithic PZT plates, ZnO films, and PVDF films). Such an advance will greatly improve diagnostic capabilities in ophthalmic ultrasound, Doppler flow measurements, dermal and epidermal imaging, and ultrasonic backscatter microscopy. Specific applications to be investigated on this program are diffraction grating transducers for Doppler flow, where tape-cast composites have the added advantage of low cost for disposable use; > 20 pachymeters for cornea thickness measurements; 30 to >50 MHz single element and annular arrays for ultrasound backscatter microscopy; and > 30 MHz linear arrays. PROPOSED COMMERCIAL APPLICATION: Existing commercial applications include diffraction grathing transducers for Doppler flow measurements, pachymeters for cornea thickness measurements, ultrasound backscatter microscopy, and improved image quality for > 15 MHz linear and phased arrays. Development of inteconnect and beam former technologies to drive > 30 MHz linear arrays will lead to applications in ophthalmic imaging, dermatology imaging, and articular imaging.