Optics and Lasers in Engineering最新文献_第4页

Magneto-optical imaging detection and classification of weld defects under alternating/rotating magnetic field excitation 交变/旋转磁场激励下焊接缺陷的磁光成像检测与分类

IF 3.5 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2024-11-14 DOI: 10.1016/j.optlaseng.2024.108679

Yanfeng Li , Xiangdong Gao , Qun Gao , Jian Liu , Yanxi Zhang , Yiwei Zhu , Wei Wu , Wei Xu

Aiming at the difficult to detect arbitrary-angle weld defects, a magneto-optical (MO) imaging non-destructive testing (NDT) system for weld defects excited by different magnetic fields is studied. The mechanism of the alternating magnetic field generated by the U-shaped yoke and the rotating magnetic field produced by the plane cross yoke is introduced, the magnetic field distribution of weld defects is analyzed by using finite element simulation. The MO imaging effects of different weld defects excited by alternating/rotating magnetic field are compared. The relationship between imaging characteristics of MO images and magnetic field strength is analyzed based on the Faraday rotation effect. The gray value of MO image can match the corresponding leakage magnetic field strength. MO imaging NDT experiments are performed on weld defects, including non-penetration, pit, surface crack, and subsurface crack. The principal component analysis (PCA) method is used to extract the grayscale features of the fused image column pixels and the texture features of the MO image are extracted by the gray-level co-occurrence matrix (GLCM). A BP-AdaBoost neural network model and a support vector machine (SVM) model are established to identify these defect features. Experimental results show that the classification accuracy of the BP-AdaBoost neural network model and the SVM model can reach 98.2 % and 98.6 % respectively under the excitation of rotating magnetic field. Compared with the alternating magnetic field, the classification accuracy is improved by 7.5 % and 8.5 %, respectively. MO imaging under rotating magnetic field excitation overcomes the limitation of directional detection of MO imaging under traditional magnetic field excitation, and realizes the detection and classification of arbitrary-angle weld defects.

针对难以检测任意角度焊接缺陷的问题，研究了一种针对不同磁场激发的焊接缺陷的磁光（MO）成像无损检测（NDT）系统。介绍了 U 形磁轭产生的交变磁场和平面十字磁轭产生的旋转磁场的机理，并使用有限元模拟分析了焊接缺陷的磁场分布。比较了交变/旋转磁场激发的不同焊接缺陷的 MO 成像效果。基于法拉第旋转效应，分析了 MO 图像的成像特征与磁场强度之间的关系。MO 图像的灰度值可与相应的泄漏磁场强度相匹配。对焊接缺陷进行了 MO 成像无损检测实验，包括非穿透、凹坑、表面裂纹和地下裂纹。采用主成分分析（PCA）方法提取融合图像列像素的灰度特征，并通过灰度级共现矩阵（GLCM）提取 MO 图像的纹理特征。建立 BP-AdaBoost 神经网络模型和支持向量机 (SVM) 模型来识别这些缺陷特征。实验结果表明，在旋转磁场的激励下，BP-AdaBoost 神经网络模型和 SVM 模型的分类准确率分别可达 98.2% 和 98.6%。与交变磁场相比，分类准确率分别提高了 7.5 % 和 8.5 %。旋转磁场激励下的 MO 成像克服了传统磁场激励下 MO 成像定向检测的局限性，实现了任意角度焊接缺陷的检测和分类。

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引用次数: 0

Projection to latent structures regression and its application to Mach–Zehnder interferometer optical fiber sensors for acetone detection 投影到潜在结构回归及其在用于丙酮检测的马赫-泽恩德干涉仪光纤传感器中的应用

IF 3.5 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2024-11-14 DOI: 10.1016/j.optlaseng.2024.108689

L.D. Hernández-Guerrero, J. Castillo-Mixcóatl, S. Muñoz-Aguirre, M. Rodríguez-Torres, E. Ramírez-Sánchez, G. Beltrán-Pérez

The techniques of multivariate analysis methods as prediction models open a new vision to the analysis of applied data. The method used in this work was projection to latent structures regression, which is a regression method that uses the latent variables generated by calculating the linear relationship between the dependent and independent variables giving them equal importance and thus obtaining the maximum variance and correlation of these variables. This method was applied to optical fiber sensors for acetone detection. It is important to detect acetone because it is a biomarker of diabetes mellitus. The sensor was fabricated with two cascaded long-period fiber gratings (LPFG) with a 515 µm grating period and separated 1 cm to form a Mach–Zehnder interferometer (MZI). Clinical studies for the diagnosis of diabetes are usually invasive, the development of these sensors proposes a new non-invasive option through the detection of acetone in human breath whose concentrations are in the order of 1.25–2.5 ppm. To study the response of the sensors to acetone, different sensing films, such as polydimethylsiloxane (PDMS), polymethyl methacrylate, Apiezon L and Apiezon T were used, which have a good affinity to this compound. Spectral changes in the transmission spectrum of the MZI were obtained due to the modes interference together with an increment of the sensitivity, since the interaction between the acetone concentration and the sensing film provokes a change in the effective index of the cladding, which in turn is amplified by the LPFGs separation. The analysis showed that the best results were obtained for the sensor with PDMS as sensing film, with the lowest limit of detection, 1.7 ppm using 4 latent structures.

作为预测模型的多元分析方法技术为应用数据分析开辟了新的视野。这项工作中使用的方法是潜在结构回归投影法，这是一种使用通过计算因变量和自变量之间的线性关系而产生的潜在变量的回归方法，给予它们同等的重要性，从而获得这些变量的最大方差和相关性。这种方法被应用于丙酮检测的光纤传感器。检测丙酮非常重要，因为它是糖尿病的生物标志物。传感器由两个级联长周期光纤光栅（LPFG）制成，光栅周期为 515 微米，相距 1 厘米，形成一个马赫-泽恩德干涉仪（MZI）。用于诊断糖尿病的临床研究通常都是侵入性的，而这些传感器的开发提出了一种新的非侵入性选择，即通过检测人体呼气中丙酮的浓度，其浓度约为 1.25-2.5 ppm。为了研究传感器对丙酮的反应，使用了不同的传感薄膜，如聚二甲基硅氧烷 (PDMS)、聚甲基丙烯酸甲酯、Apiezon L 和 Apiezon T，它们对这种化合物有很好的亲和力。由于丙酮浓度和传感薄膜之间的相互作用会引起包层有效指数的变化，而这种变化又会被 LPFGs 分离放大，因此 MZI 的透射光谱会因模式干扰而发生光谱变化，同时灵敏度也会提高。分析表明，使用 PDMS 作为传感膜的传感器效果最好，使用 4 个潜伏结构的检测限最低，为 1.7 ppm。

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引用次数: 0

Research on the Al/Cu dissimilar metals laser welding process with alternating magnetic field assisted 交变磁场辅助铝/铜异种金属激光焊接工艺研究

IF 3.5 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2024-11-09 DOI: 10.1016/j.optlaseng.2024.108686

Longfei Zhang, Haoyuan Tan, Haozhong Lin, Pengcheng Lv, Lin Lin, Jun Zhou

Superior Al/Cu dissimilar metal joints is crucial for the development of the new energy electric vehicle industry. This study aims to enhance the mechanical properties of Al/Cu joints while minimizing their electrical contact resistance. Laser lap welding of 5A06 Al and T2 Cu was conducted applying an Alternating magnetic field (AMF) assisted method at various frequencies. Surface fluctuations, joint strength, and electrical contact resistance were compared with those of joints welded without the application of magnetic fields. The application of an AMF reduced the surface fluctuation of Al/Cu joints by 34.67 %, significantly improving the surface quality of the joints. Microscopic analysis of the welded joints reveals that, under the influence of the AMF, the α-Al and Al-Cu eutectic phase transform to Al₂Cu and a mixture of α-Al and Al-Cu eutectic phase in the middle of the molten pool. Simultaneously, the Cu-rich Al₄Cu₉ phase is no longer observed at the bottom of the molten pool. Additionally, Al-Cu intermetallic compounds (IMCs), particularly Al₂Cu, which accumulate at the junction of the bottom of the molten pool, are effectively dispersed under the action of the AMF. The growth of small Al₂Cu is inhibited by the alternating Lorentz force, leading to simultaneous enhancements in both the mechanical properties and electrical conductivity of the Al/Cu joint. Tensile properties and electrical contact resistance measurements show that the shear resistance of the Al/Cu joints is improved by up to 19.03 %, and the electrical contact resistance is reduced by 1.2 % under the AMF-assisted condition at 150 Hz. In this study, AMF-assisted laser welding of Al/Cu significantly enhances the mechanical properties of the joints while reducing their electrical contact resistance. These findings provide valuable reference for producing superior Al/Cu joints for batteries in new energy electric vehicles.

优异的铝/铜异种金属接头对于新能源电动汽车行业的发展至关重要。本研究旨在提高铝/铜接头的机械性能，同时将其电气接触电阻降至最低。采用交变磁场 (AMF) 辅助方法，在不同频率下对 5A06 铝和 T2 铜进行了激光搭接焊接。将表面波动、接头强度和电接触电阻与未应用磁场的焊接接头进行了比较。使用交变磁场将铝/铜接头的表面波动降低了 34.67%，显著改善了接头的表面质量。焊接接头的显微分析表明，在 AMF 的影响下，α-Al 和 Al-Cu 共晶相转变为 Al2Cu 以及熔池中间的 α-Al 和 Al-Cu 共晶相混合物。同时，在熔池底部不再观察到富含铜的 Al4Cu9 相。此外，在 AMF 的作用下，积聚在熔池底部交界处的铝铜金属间化合物（IMC），特别是 Al2Cu，也被有效分散。交变洛伦兹力抑制了小的 Al2Cu 的生长，从而同时提高了 Al/Cu 接头的机械性能和导电性。拉伸性能和电接触电阻测量结果表明，在 150 Hz 的 AMF 辅助条件下，铝/铜接头的抗剪性能提高了 19.03%，电接触电阻降低了 1.2%。在这项研究中，AMF 辅助激光焊接铝/铜显著提高了接头的机械性能，同时降低了其电气接触电阻。这些发现为生产用于新能源电动汽车电池的优质铝/铜接头提供了宝贵的参考。

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引用次数: 0

Super-oscillation sub-diffraction focusing with emulated atmospheric turbulence 利用模拟大气湍流进行超振荡子衍射聚焦

IF 3.5 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2024-11-09 DOI: 10.1016/j.optlaseng.2024.108675

Na Yao , Jiao Jiao , Jingxuan Duan , Mo Chen , Duanpeng He

The super-oscillation (SO) phenomena successfully applied to super-resolution optical telescopes have yet to study the existence of atmospheric turbulence (AT). In this paper, we first experimentally investigate the sub-diffraction focusing of the SO light field in the atmospheric-like turbulence. The 137-element adaptive optics (AO) system is utilized to correct the dynamic wavefront aberration produced by the AT and obtain the AO closed-loop RMS of the residual wavefront error ∼λ/15. For a proofed telescope (clear aperture 12 mm and focal length 1000 mm) @λ=632.8 nm, the FWHM of the experimental SO spot under the modest AT (wavefront error RMS ∼0.57λ) is about 0.79 times of the Airy spot compared with the non-AT result of 0.76 times, while the strong AT (wavefront error RMS ∼1.35λ) erases the sub-diffraction focusing effect of the SO field and the average side-lobe intensity increases significantly. This study is promising for super-resolving telescope, synthetic aperture for visible imaging, etc.

成功应用于超分辨率光学望远镜的超振荡（SO）现象尚未研究大气湍流（AT）的存在。在本文中，我们首先通过实验研究了类大气湍流中 SO 光场的次衍射聚焦。利用 137 元自适应光学（AO）系统校正 AT 产生的动态波前像差，并获得 AO 闭环残余波前误差 RMS ∼λ/15。对于经过校准的望远镜（透明孔径 12 mm，焦距 1000 mm）@λ=632.8 nm，在适度 AT（波前误差均方根∼0.57λ）下，实验 SO 光斑的 FWHM 约为 Airy 光斑的 0.79 倍，而非 AT 的结果为 0.76 倍；而在强 AT（波前误差均方根∼1.35λ）下，SO 场的次衍射聚焦效应被消除，平均侧叶强度显著增加。这项研究有望用于超分辨望远镜、可见光成像合成孔径等。

引用次数: 0

A DIC-FEM hybrid method for measuring strains near fiber-matrix interface of CFRP cross section 用于测量 CFRP 截面纤维-基体界面附近应变的 DIC-FEM 混合方法

IF 3.5 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2024-11-09 DOI: 10.1016/j.optlaseng.2024.108682

A. Nakachi, S. Yokoyama, K. Iizuka, S. Yoneyama

A DIC-FEM hybrid method is proposed to capture micro-scale deformation behavior near the fiber-matrix interface by combining displacement distributions measured using digital image correlation (DIC) with finite element method (FEM) analysis. Images of CFRP cross section with fine random pattern before and after deformation are taken with a laser microscope. The in-plane displacement components near the interface of fiber and matrix are obtained using digital image correlation and they are used as the input of the hybrid method. Not only the displacement distributions but the strain fields are determined using the proposed hybrid method, based on the superposition principle, so that the same distributions are obtained as those obtained by the measurement. The proposed DIC-FEM hybrid provides the strains near the interface between fiber and matrix, compensating for the insufficient resolution of microscope images.

通过将数字图像相关（DIC）测量的位移分布与有限元法（FEM）分析相结合，提出了一种 DIC-FEM 混合方法，用于捕捉纤维-基体界面附近的微尺度变形行为。用激光显微镜拍摄变形前后带有精细随机图案的 CFRP 截面图像。利用数字图像相关技术获得了纤维和基体界面附近的平面内位移分量，并将其作为混合方法的输入。根据叠加原理，所提出的混合方法不仅能确定位移分布，还能确定应变场，从而获得与测量结果相同的分布。拟议的 DIC-FEM 混合法提供了纤维与基体界面附近的应变，弥补了显微镜图像分辨率不足的问题。

引用次数: 0

Machine learning assisted distributed low pressure measurement based on optical carrier-based microwave interferometry 基于光载波微波干涉测量法的机器学习辅助分布式低压测量技术

IF 3.5 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2024-11-08 DOI: 10.1016/j.optlaseng.2024.108681

Zhuping Li , Ting Xue , Songlin Li , Yan Wu , Bin Wu

The distributed measurement of low pressure utilizing common optical fibers without sensitization is desired but challenging in many industrial applications. In this paper, with the assistance of machine learning, the distributed measurement of low hydrostatic pressure is realized based on optical carrier-based microwave interferometry (OCMI) employing the common single-mode fiber (SMF). Firstly, the theoretical model of pressure sensitivity is established, and further investigated and validated by numerical simulation and finite element simulation. Subsequently, a distributed hydrostatic pressure measurement experiment is conducted utilizing a common SMF with cascaded weak light reflectors processed along the fiber core. The results indicate that it is difficult to measure low pressure through common fibers based on the traditional demodulation method. To overcome the above limitations, we propose to employ machine learning to analyze the microwave interference information, in order to achieve a one-to-one mapping with the hydrostatic pressure exerted on the sensing fiber. The implementation of distributed pressure measurement is based on the unique advantages of OCMI in terms of physical positioning and reconfigurable gauge length. Meanwhile, different microwave interferometric information is employed as inputs for comparison to select the most effective signals for optimal prediction. The results show that a satisfactory overall measurement and distributed measurement of low hydrostatic pressure can be achieved with the assistance of machine learning, where the accuracy of distributed measurement increases with the increase of Fabry-Perot interferometer (FPI) cavity length. The proposed strategy can be extended to other relatively short-distance spatially continuous distributed or long-distance quasi-distributed fiber sensing systems.

在许多工业应用中，利用普通光纤进行无敏化低压分布式测量是人们所期望的，但也是具有挑战性的。本文在机器学习的帮助下，利用普通单模光纤（SMF），基于光载波微波干涉仪（OCMI）实现了低静压的分布式测量。首先，建立了压力灵敏度的理论模型，并通过数值模拟和有限元模拟进行了进一步研究和验证。随后，利用沿纤芯处理级联弱光反射器的普通 SMF 进行了分布式静水压力测量实验。结果表明，传统的解调方法很难通过普通光纤测量低压。为了克服上述局限性，我们建议采用机器学习来分析微波干扰信息，从而实现与施加在传感光纤上的静水压力的一一对应。分布式压力测量的实现基于 OCMI 在物理定位和可重新配置测量长度方面的独特优势。同时，采用不同的微波干涉测量信息作为输入进行比较，以选择最有效的信号进行优化预测。结果表明，在机器学习的帮助下，可以实现令人满意的低静水压整体测量和分布式测量，其中分布式测量的精度随着法布里-珀罗干涉仪（FPI）腔长的增加而提高。所提出的策略可扩展到其他相对短距离的空间连续分布式或长距离准分布式光纤传感系统。

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引用次数: 0

Polarimetric image denoising via non-local based cube matching convolutional neural network 通过基于非局部立方匹配的卷积神经网络实现极坐标图像去噪

IF 3.5 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2024-11-08 DOI: 10.1016/j.optlaseng.2024.108684

Hedong Liu , Xiaobo Li , Zhenzhou Cheng , Tiegen Liu , Jingsheng Zhai , Haofeng Hu

Due to rapid advances in deep learning, many polarimetric image denoising networks have been developed and achieved promising results. However, these methods are based on general network architectures that do not fully exploit problem-specific knowledge, leading to over-smoothing results and poor generalization. Inspired by the non-local, which is an effective prior for image restoration, we propose a cube matching convolutional neural network to incorporate non-local operations into denoising models for polarimetric images. Specifically, the cube matching technique allows the denoising network to simultaneously exploit the non-local correlation and polarization relationship between the corresponding voxels of similar cubes. Rather than applying self-similarity directly in an isolated manner, the proposed cube matching module can be flexibly integrated into existing deep networks by combining with 3D convolution, achieving an effect equivalent to non-local means. This design enhances the generalization ability against various types and levels of noise. Experimental results show that using cube matching operations significantly improves denoising performance.

由于深度学习的快速发展，许多偏振图像去噪网络被开发出来并取得了可喜的成果。然而，这些方法都是基于一般的网络架构，不能充分利用特定问题的知识，导致过度平滑结果和泛化效果不佳。非局部是图像复原的有效先验，受此启发，我们提出了一种立方体匹配卷积神经网络，将非局部操作纳入偏振图像的去噪模型中。具体来说，立方体匹配技术允许去噪网络同时利用相似立方体对应体素之间的非局部相关性和偏振关系。所提出的立方体匹配模块不是以孤立的方式直接应用自相似性，而是通过与三维卷积相结合，灵活地集成到现有的深度网络中，达到与非局部手段相当的效果。这种设计增强了对各种类型和程度噪声的泛化能力。实验结果表明，使用立方体匹配操作能显著提高去噪性能。

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引用次数: 0

An improved quaternary complementary Gray code phase unwrapping method in fringe projection profilometry 边缘投影轮廓测量中的改进型四元互补格雷码相位解除方法

IF 3.5 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2024-11-08 DOI: 10.1016/j.optlaseng.2024.108680

Xuan Li , Hongru Li , Hao Wei , Sha Wang , Songsong Zhu , Nan Jiang , Chao Yang , Guoliang Deng

This paper presents a phase unwrapping method utilizing an improved quaternary complementary Gray code in fringe projection profilometry. Traditional methods often require a high number of additional projection patterns, which are aimed to be minimized. The proposed approach decomposes the last quaternary Gray code pattern into two binary Gray codes, integrating a complementary strategy for error prevention. This method enhances the accuracy of order calculation while retaining the efficiency of the quaternary Gray code. To obtain the codewords corresponding to the four grayscale levels more conveniently and accurately, a point-to-point threshold segmentation strategy is introduced to enhance segmentation. Additionally, an isolated order correction strategy is proposed to mitigate noise-induced errors. Experimental results validate the feasibility and superiority of the method over conventional techniques, demonstrating its improved efficiency and robustness.

本文介绍了一种在条纹投影轮廓测量中利用改进的四元互补格雷码进行相位解包的方法。传统方法通常需要大量额外的投影图案，目的是尽量减少这些图案。所提出的方法将最后一个四元灰度编码模式分解为两个二进制灰度编码，并整合了一种互补策略来防止错误。这种方法既提高了阶次计算的准确性，又保留了四阶格雷码的效率。为了更方便、更准确地获得与四个灰度级相对应的编码，引入了点对点阈值分割策略，以增强分割效果。此外，还提出了一种孤立阶校正策略，以减轻噪声引起的误差。实验结果验证了该方法的可行性和优于传统技术的优势，证明了其效率和鲁棒性的提高。

引用次数: 0

Omnidirectional all-solid-state aliasing-free scanning using liquid crystal optical phased array and conical mirror 利用液晶光学相控阵和锥形镜进行全向全固态无混叠扫描

IF 3.5 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2024-11-07 DOI: 10.1016/j.optlaseng.2024.108664

Jie Cao , Shuanglong Zhou , Yang Cheng , Qun Hao

Optical phased array (OPA) is a promising solid-state beam steering method. However, small scanning field of view (FOV) and grating lobes aliasing constraint its applications. Therefore, an omnidirectional all-solid-state aliasing-free scanning method which is implemented by two-dimensional liquid crystal OPA and conical mirror is presented. Experimental results demonstrate desired scanning with FOV of 360° × 1.1° and scanning error is less than 0.2° × 0.03°, without moving parts and grating lobes aliasing.

光学相控阵（OPA）是一种很有前途的固态光束转向方法。然而，较小的扫描视场（FOV）和光栅裂片混叠限制了它的应用。因此，本文提出了一种全向全固态无混叠扫描方法，该方法由二维液晶 OPA 和锥形镜实现。实验结果表明，该方法的扫描范围为 360° × 1.1°，扫描误差小于 0.2° × 0.03°，且无移动部件和光栅裂片混叠现象。

引用次数: 0

Non-null test of cylindrical surfaces with complex parameters based on pseudo shearing interferometry 基于伪剪切干涉测量法的复杂参数圆柱面非零测试

IF 3.5 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2024-11-06 DOI: 10.1016/j.optlaseng.2024.108687

Yang Chen , Kuo Hai , Xin Zhang , Siqi Zhang , Yueqing Zheng , Qian Liu , Xing Su , Wen Huang , Xiaodong Zhang , Dong Liu , Zhongming Zang

Cylindrical surfaces with complex parameters (CSCP), including off-axis, aspheric, and other properties, provide higher degrees of design freedom than cylindrical surfaces with spherical cross-sections. Thus, they can better satisfy the requirements of complex optical systems. To the best of our knowledge, we present a novel non-null test method for the CSCP: two-dimensional pseudo lateral shearing interferometry (2DPLSI). During the measurement process, the test surface translates along orthogonal directions, and the figure error is reconstructed by a method similar to lateral shearing interferometry. Our approach strongly reduces the retrace error inherent to non-null test and other errors, including the figure error of the compensating lens and the system error. The reduction of errors facilitates the design of the compensating lens, and a spherical cylinder suffices to meet the requirements. Furthermore, we analyze the misalignment aberrations introduced by the orthogonal displacement in non-null interferometry and propose a calibration method to achieve high precision measurement. The experimental results demonstrate that the root-mean-square (RMS) value of the difference map compared with null test is better than λ/50 (λ = 632.8 nm), and the repeatability of the proposed method is superior to λ/200 RMS.

与具有球形截面的圆柱面相比，具有复杂参数（CSCP）的圆柱面（包括离轴、非球面和其他特性）可提供更高的设计自由度。因此，它们能更好地满足复杂光学系统的要求。据我们所知，我们提出了一种新型的 CSCP 非空测试方法：二维伪侧向剪切干涉测量法（2DPLSI）。在测量过程中，测试表面沿正交方向平移，通过类似于横向剪切干涉测量的方法重建图形误差。我们的方法大大减少了非空测试固有的回溯误差和其他误差，包括补偿透镜的图形误差和系统误差。误差的减少为补偿透镜的设计提供了便利，球面圆柱体足以满足要求。此外，我们还分析了在非空干涉测量中由正交位移引入的错位像差，并提出了一种实现高精度测量的校准方法。实验结果表明，与空测相比，差分图的均方根值优于 λ/50 (λ = 632.8 nm)，而且所提方法的重复性优于 λ/200 均方根值。

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引用次数: 0