Weaver J R, Daft C W, Briggs G D
IBM Thomas J. Watson Res. Center, Yorktown Heights, NY.
IEEE Trans Ultrason Ferroelectr Freq Control. 1989;36(5):554-60. doi: 10.1109/58.31800.
An acoustic microscope that permits operation with both toneburst and impulse excitation of the lens is presented. Either mode can be selected and combined with mechanical scanning in any direction. In the impulse-excited mode, the specular and Rayleigh signals from the sample are resolved in time, and analysis is performed to obtain surface wave propagation parameters. The power of the simultaneous application of these techniques is illustrated by measurements on specimens of intact and fractured glass and duraluminum. Reflection and transmission coefficients for a crack are measured, and conclusions are drawn about V(z) processing. These results are significant because the images of cracks produced by the conventional toneburst scanning acoustic microphone (SAM) tend to be complex. Diffraction from the tips of cracks is observed in the microscope.
本文介绍了一种声学显微镜，该显微镜允许在透镜的猝发声和脉冲激发两种模式下运行。可以选择任一模式，并与任意方向的机械扫描相结合。在脉冲激发模式下，来自样品的镜面反射信号和瑞利信号在时间上得到分辨，并进行分析以获得表面波传播参数。通过对完整和断裂的玻璃及硬铝样品的测量，说明了同时应用这些技术的威力。测量了裂纹的反射和透射系数，并得出了关于V(z)处理的结论。这些结果具有重要意义，因为传统的猝发声扫描声学显微镜（SAM）产生的裂纹图像往往很复杂。在显微镜中观察到了裂纹尖端的衍射现象。
