MULTI-FREQUENCY ARRAY FOR HARMONIC IMAGING

提出的研究将开发一种新的，高动态范围的多频换能器阵列，设计用于宽带组织成像。新阵列将利用相同或不同材料的元件在不同厚度模式下谐振，以允许在次谐波、一谐波和二谐波频率下工作。一个元件将被优化用于发送，另外两个元件将被优化用于接收。在本研究中，一谐波发射/接收频率为5.0 MHz，对应的次谐波回波和次谐波回波分别为2.5 MHz和10.0 MHz。在第一阶段，在罗格斯大学陶瓷研究中心的支持下，分层制造公司将开发一个由三个平行阵列组成的三种不同频率的小型共线性阵列。压电陶瓷换能器阵列将利用专利的分层制造技术制造，该技术非常适合医学成像常用的频率范围（1-10 MHz）。可行性论证将包括用基于微泡的超声造影剂测量流体的散射回波。在第二阶段，将制作一个二维阵列，散布多频率换能器元件，以及用于对动物成像的各种成像模式，使用或不使用超声造影剂。建议的商业应用：如果多频率换能器阵列的设计证明是成功的，那么分层制造公司准备将该技术授权给所有超声系统公司。LMI还准备在商业上为特定应用提供特殊的换能器阵列，特别是在10mhz以上的高频下。

The proposed study will develop a novel, high dynamic range multi- frequency transducer array designed for broad-band tissue imaging. The new array would utilize elements of the same or different materials resonating in different thickness modes to permit operating at the subharmonic, first harmonic and second harmonic frequencies. One element will be optimized for transmit and the other two optimized for receive. In this study, the first harmonic transmit/receive frequency will be 5.0 MHz with corresponding subharmonic and second harmonic echoes at 2.5 MHz and 10.0 MHz, respectively. In Phase I, Layered Manufacturing Inc., with the support of the Center for Ceramic Research of Rutgers University, will develop a small co-linear array of three parallel arrays at three different frequencies. The piezoceramic transducer arrays will be fabricated utilizing patented layered manufacturing techniques that are ideally suited for the frequency regime common to medical imaging (1-10 MHz). A feasibility demonstration will include the measurement of the scattered echo returns from a fluid with a microbubble- based ultrasound contrast agent. In Phase II, a 2-D array will be fabricated, interspersed with multi-frequency transducer elements, and the various imaging modes used to image animals, with and without an ultrasound contrast agent. PROPOSED COMMERCIAL APPLICATIONS: If the design of a multi-frequency transducer array proves successful, then Layered Manufacturing Inc. is prepared to license the technology to all ultrasound system companies. LMI is also prepared to commercially provide special transducer arrays for specific applications, particularly at high frequencies, above 10 MHz.