ABSTRACT Currently, the primary method employed by ultrasound inspection systems is based on applying pulsed sound/ultrasound energy to the inspected part, and detecting reflected/transmitted pulses. Typically, pulse-based methods are essentially time-domain back-reflection methods, and time-of-flight is the main measured parameter. Recently, continuous-wave frequency-domain back-reflection meters were developed in the radar and in the fiber optics fields, which demonstrate significantly better spatial resolution, higher SNR, and ability to detect reflecting objects at very short distances. The same approach was used in this paper to develop a prototype continuous-wave ultrasound inspection system. The parameters of the prototype system are described, and the advantages and limitations of the continuous-wave ultrasound inspection method are discussed. Examples of the use of the system are presented.

中文翻译：

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频域连续波超声反射法无损检测

摘要目前，超声检测系统采用的主要方法是将脉冲声/超声能量应用于被检测部件，并检测反射/传输脉冲。通常，基于脉冲的方法本质上是时域背反射方法，飞行时间是主要的测量参数。最近，连续波频域背向反射计在雷达和光纤领域得到了发展，显示出明显更好的空间分辨率、更高的信噪比以及在很短距离内检测反射物体的能力。本文使用相同的方法开发了原型连续波超声检测系统。描述了原型系统的参数，并讨论了连续波超声检查方法的优点和局限性。介绍了该系统的使用示例。