用于隐藏物探测的2.24 THz激光实时成像实验

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成像速度和质量是衡量太赫兹(THz)成像系统的关键因素。采用连续功率约10 mW的CO2激光抽运2.24 THz激光作为成像光源,利用像元数为124×124的热像仪作为面阵探测器,进行了隐藏物探测成像实验。实验中分别采用纸和聚乙烯信封作为遮挡物,获得了原始数据,并在此基础上运用一些图像预处理方法,以提高图像质量。实时成像结果显示,利用2.24 THz激光实时成像系统,可以对穿过纸和信封后的物体进行成像,物体轮廓基本可见。由于激光功率较低,图像质量不好,但经过后续的图像预处理,使得图像中物体轮廓较清晰。因此,在提高THz激光输出功率的基础上,利用图像预处理方法可以使图像更清晰。
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