基于光流的光纤材料三维微形变无包络测量方法

Optical-fiber material products are widely used in such fields as night-vision, aeronautical and electronics technologies. Micro-scale deformation will be produced in this kind of products as they are under physical or chemical conditions in the course of service and production, which will seriously influence the performance and safe reliability of instruments. The existing optical metrology and microscanning methods cannot realize the whole field three-dimensional(3D) deformation measurement. In order to solve this problem, a three-dimensional micro-scale deformation measurement method based on optical flow is proposed. The optical flow response mechanism for the out-of-plane deformation phase of material image, the local frequency characteristics of array image and the image enhancement methods et. al. are studied in this project, subsequently the micro-deformation reconfiguration without phase unwrapping can be realized. The innovations and contributions of this project will provide new application field for optical flow-based recognition technique and an effective method for 3D deformation measurement of optical fiber material, which have a wide application prospect in night-vision manufacturing industry.

光纤材料制品现被广泛应用于夜视、航天、电子等领域中，该类材料制品在生产与服役过程中易受到各种理化作用而产生微尺度形变，危及仪器性能与安全可靠性，而现有的光学计量、显微扫描等方法难以对其进行全场三维形变快速测量。为解决这一问题，本项目提出一种基于光流的三维微尺度形变检测方法。通过研究材料形变图像中离面形变的光流响应机理，阵列图像的条纹频率的表征与提取方法，图像增强方法等，实现微尺度形变的无包络重构。项目研究成果将为光流检测技术开辟新的应用领域，也为光纤材料的三维形变快速测量提供一种有效的新方法，在夜视制造业中具有广阔的应用前景。

光纤传像材料（如光纤面板、倒像器、微通道板等）是微光夜视仪的核心器件，在夜视、航天、电子、等领域有重要的应用。在生产和服役过程中，该类材料都会经历多种理化作用而不可避免地产生不同程度的形变，如酸碱腐蚀、研磨抛光、氢气热还原、高温热压等。虽然此形变量较小，仅有微米甚至纳米尺度，但是足以严重影响光纤材料的分辨率、耦合效率等重要性能，对设备造成严重损伤，而现有的光学测量、显微扫描等方法无法满足光纤传像材料的三维形变快速工业检测需求。为解决这一问题，本项目基于微分理论建立了显微镜下的图像楔面化模型，在微观情况下将光纤材料的面内位移与离面位移用数学关系式联系到一起，利用信号学中的光流算法同时提取了材料的三维位移场，实现了光纤传像材料在显微镜下的三维形变快速检测。实验结果表明，本方法在50倍光学显微镜下的测量精度可达0.2μm以上。该方法充分利用了面内位移场携带的离面位移信息，提取离面位移时无需转换到频域和相位解包操作，具有检测成本低、光路简单、普适性强、稳定性高等优势，目前已被用于玻璃光纤、石英光纤等光学产品的工业生产检测与监控中，同时为其它固体材料的微纳米尺度形变动态测量提供了新的思路。