相位成象声显微镜的研制及应用  

DEVELOPMENT AND APPLICATION OF A PHASE SCANNING ACOUSTIC MICROSCOPE

作　　者：陈戈林[1] 董方源[1] 王国功[1] 

机构地区：[1]清华大学电子工程系,北京100084

出　　处：《无损检测》2001年第9期375-379,共5页Nondestructive Testing

摘　　要：研制了一台相位成象声显微镜 ,可对样品反射信号的相位信息进行成象。其电路由插入PC机内的超高速A/D卡和快脉冲产生和接收卡组成。A/D卡采样率 >10 9次 /s ,使用了周边元件扩展接口 (PCI)总线和现场可编程门阵列 (FPGA)技术 ;脉冲产生和接收卡能可靠接收、放大未经检波的回波 ,因而可精确获取未经检波的回波信号。然后利用软件完成相位检测及图象显示 ,还可通过数字检波获得样品幅度象。仪器工作频率为 2 5 0MHz ;可实时显示检测样品的A扫描及相位或幅度象。该仪器在微米级薄膜厚度、形状的测量和三维成象以及焊接质量的检测等方面具有独特功能。该机体积小、功能强、成本低 。A phase scanning acoustic microscope has been developed, which can detect the phase information of the reflected waves and show the phase image. The hardware of the instrument consists of a superhigh speed A/D converting card and a fast pulse generating and signal receiving card. The A/D converter, in which PCI bus and FPGA technologies are used, has a sampling rate of over 10 9 samples per second. The fast pulse generating and signal receiving card can reliably receive and amplify the reflected waves that are not demodulated. So the original reflected waves can be acquired precisely. Phase detecting and imaging are realized by software. We can also attain amplitude image through digital demodulation. The operating frequency can vary from 2MHz to 50MHz. The real time result of phase or amplitude image is displayed on the screen of PC terminal and the A mode scan can be accomplished at the same time. The system has been successfully applied to testing some kinds of specimens, especially to the measurement of the thickness and shape of metal film and the quality inspection of sealed objects. It can be used in many areas for its powerful function, small volume and low cost.

关 键 词：声显微镜 相位 成象 硬件 软件 研制 

分 类 号：TH742[机械工程—光学工程]