基于FPGA的高分辨超声快速扫描成像系统研制

Development of High Resolution Ultrasonic Rapid Scan Imaging System Based on FPGA

针对超声C扫描成像系统步进式扫描方式速度慢的缺点,研制了一套基于FPGA技术的超声快速扫描成像系统,实现超声换能器在扫描平台连续运动过程中回波信号的快速采集与传输。系统将高精度点聚焦超声显微测试平台和FPGA硬件化信号采集和处理技术相结合,采用FPGA技术进行数位信号的高速采集和处理,利用幅值法和时间法进行回波信号特征值提取,实现了超声快速扫描成像。利用该系统分别对特制试件幅值法和时间法的成像分辨率进行分析;并对硬币和电子封装芯片进行扫描成像测试。结果表明,系统扫描速度快,检测结果直观,成像分辨率高,横纵向分辨力可达50μm,不仅可实现快速清晰成像,而且可进行微小结构的检测,为材料内部缺陷快速检测成像奠定了基础。

Since the speed weakness of the step-scanning mode of ultrasonic C-scan imaging technology,an ultrasonic rapid scan imaging system based on the FPGA technology was developed. It can achieve the fast data acquisition and transmission for the echo signals by ultrasonic transducer during the continuous motion of the scanning platform. Combining high precision point focused ultrasound microscopic test platform with FPGA hardware signal acquisition and processing technology,this system employs the FPGA technology to realize the high-speed signal acquisition and processing and uses amplitude and time method to extract echo signal eigenvalue,achieving ultrasonic rapid scan imaging. The system was applied to analyze the amplitude and time method resolution of the special specimen respectively and to accomplish the scanning imaging test of coins and electronic packaging chips. The results show that the system has fast testing speed,intuitive test results,high imaging resolution with horizontal and vertical resolving power up to 50 μm. The system can realize fast clear imaging,and small structures detection. Meanwhile,it also laid the foundation for the rapid detection and imaging of internal defects in materials.