The detection of crack on materials is an important issue in industry. On the contrary to conventional methods, such as manual inspection, sensor detection, and image processing techniques, a new simple method to detect the crack is proposed with optical voice recorder based on digital holography in this paper. Holograms obtained with sound waves passing through the materials are recorded by using the digital holography technique. Temporal behavior of the sound wave passing through the material, which is obtained from these holograms, gives image of crack. In this article, cracks in various materials are determined by the proposed new method, and crack images obtained with this new system are presented.

中文翻译：

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基于数字全息的光学录音机裂纹检测

材料裂纹的检测是工业中的重要问题。与传统方法，如人工检查，传感器检测和图像处理技术相反，本文提出了一种基于数字全息技术的光学语音记录器检测裂缝的简单方法。使用数字全息技术记录声波穿过材料获得的全息图。从这些全息图获得的穿过材料的声波的时间行为给出了裂纹图像。在本文中，通过提出的新方法确定了各种材料中的裂纹，并给出了使用该新系统获得的裂纹图像。