Optical coherence tomography (OCT), as an optical interferometric imaging technique, has found wide applications in various fields. In principle, OCT is well suited for imaging layered structures, and thus, one of the typical applications is thickness measurement. However, due to the limited imaging depth resulting from light attenuation, thickness measurement by OCT is limited to non-opaque materials. In this study, we developed a novel (to the best of our knowledge) dual-side view OCT (DSV-OCT) system for thickness measurement on opaque materials. The dual-side view was achieved on a conventional swept source OCT platform by creating two symmetrical sampling arms. This allows us to image both sides of the material simultaneously and produce the surface contours of the two sides in a single C scan. Finally, the thickness of the opaque material can be calculated from the two surface contours above. We demonstrated that our DSV-OCT technique can measure the thickness of opaque material with an accuracy of about 3 µm.

中文翻译：

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双面光学相干断层扫描，用于不透明材料的厚度测量。

光学相干断层扫描（OCT）作为一种光学干涉成像技术，已在各个领域得到了广泛的应用。原则上，OCT非常适合对分层结构进行成像，因此，典型的应用之一是厚度测量。但是，由于光衰减导致成像深度有限，因此通过OCT进行的厚度测量仅限于非透明材料。在这项研究中，我们开发了一种新颖（据我们所知）的双面OCT（DSV-OCT）系统，用于不透明材料的厚度测量。通过创建两个对称的采样臂，可以在常规扫频源OCT平台上获得双面视图。这使我们可以同时对材料的两面进行成像，并在单次C扫描中产生两面的表面轮廓。最后，不透明材料的厚度可以根据上面的两个表面轮廓来计算。我们证明了我们的DSV-OCT技术可以测量不透明材料的厚度，精度约为3 µm。