Tu Haibo, Bu Xingying, Liao Ran, Zhang Hailong, Ma Guoliang, Li Hening, Wan Jiachen, Ma Hui
Department of Physics, Yangtze University, Jingzhou 434100, China.
Shenzhen Key Laboratory of Marine IntelliSensing and Computation, Guangdong Research Center of Polarization Imaging and Measurement Engineering Technology, Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
Materials (Basel). 2023 Jun 30;16(13):4733. doi: 10.3390/ma16134733.
Safety of the observation window is one of the core concerns for manned submersibles. When subjected to underwater static pressure, extrusion and creep deformation always occur in the observation window, which can pose a threat to both safety and optical performance. To assess the deformation, real-time and non-contact monitoring methods are necessary. In this study, a conceptual setup based on the waveplate rotation and dual-DoFP (division of focal-plane polarimeter) polarization camera is built for the observation window's creep monitoring by measuring the Mueller matrix images of the samples under different pressures and durations. Then, a series of characteristic parameters, such as , , , ', are extracted from the Muller matrix images by Mueller matrix transformation (MMT), Mueller matrix polar decomposition (MMPD), correlation analysis and phase unwrapping method. The results demonstrate that these parameters can effectively describe the observation window's creep at different pressure levels which are simulated by finite element analysis. Additionally, more characterization parameters, such as , and , are given from the Mueller matrix images and discussed to illustrate the method's potential for further applications and investigations. Ultimately, future devices based on this method could serve as a valuable tool for real-time and non-contact creep monitoring of the submersible observation windows.
观察窗的安全性是载人潜水器的核心关注点之一。在水下静压作用下，观察窗总会发生挤压和蠕变变形，这会对安全性和光学性能都构成威胁。为了评估变形情况，实时和非接触监测方法是必要的。在本研究中，构建了一种基于波片旋转和双DoFP（焦平面偏振计）偏振相机的概念装置，用于通过测量不同压力和持续时间下样品的穆勒矩阵图像来监测观察窗的蠕变。然后，通过穆勒矩阵变换（MMT）、穆勒矩阵偏振分解（MMPD）、相关分析和相位展开方法从穆勒矩阵图像中提取一系列特征参数，如 、 、 、' 。结果表明，这些参数可以有效地描述通过有限元分析模拟的不同压力水平下观察窗的蠕变情况。此外，从穆勒矩阵图像中给出了更多的表征参数，如 、 和 ，并进行了讨论，以说明该方法在进一步应用和研究方面的潜力。最终，基于该方法的未来设备可作为潜水器观察窗实时和非接触蠕变监测的有价值工具。
