Mid-infrared signals in the 2–5 μm wavelength range have been transmitted through samples of polymer pipes, as commonly used in the water supply industry. It is shown that simple through-transmission images can be obtained using a broad spectrum source and a suitable camera. This leads to the possibility of tomography, where images are obtained as the measurement system is rotated with respect to the axis of the pipe. The unusual 3D geometry created by a source of finite size and the imaging plane of a camera, plus the fact that refraction at the pipe wall would cause significant ray bending, meant that the reconstruction of tomographic images had to be considered with some care. A result is shown for a thinning defect on the inner wall of a polymer water pipe, demonstrating that such changes can be reconstructed successfully.

中文翻译：

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聚合物管道的中红外断层扫描

2-5 μm 波长范围内的中红外信号已通过聚合物管道样本传输，这在供水行业中很常用。结果表明，使用广谱光源和合适的相机可以获得简单的透射图像。这导致了断层扫描的可能性，其中当测量系统相对于管道的轴旋转时获得图像。由有限尺寸的光源和相机的成像平面创建的不寻常的 3D 几何形状，加上管壁处的折射会导致显着的光线弯曲，这意味着必须谨慎考虑断层图像的重建。显示了聚合物水管内壁变薄缺陷的结果，表明可以成功重建此类变化。