Optics and Laser Technology最新文献_第3页

Spatial-frequency-division-multiplexed edge-core Bragg grating Fabry-Perot interferometer for biaxial inclination sensing 用于双轴倾角传感的空间频分复用边芯布拉格光栅法布里-珀罗干涉仪

IF 5 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2026-06-01 Epub Date: 2026-02-10 DOI: 10.1016/j.optlastec.2026.114909

Benyue Li , Daryl Tan , Kok-Sing Lim , Shufeng Sun , Fengyi Chen

A novel three-reflector fibre Bragg grating Fabry–Perot interferometer (3R-FPI) based on femtosecond (fs) laser direct writing is proposed and experimentally demonstrated for inclination angle detection. The sensor structure consists of three short Bragg gratings, including one standard core grating and two edge-core gratings inscribed at precise positions along a single-mode fiber. The combination of edge-core and core gratings enables bending-induced asymmetrical electric field distribution to be effectively converted into optical intensity variations. Two 3R-FPI configurations are fabricated with carefully designed cavity lengths to generate distinct, non-overlapping spatial frequency components in the spatial frequency domain, thereby allowing efficient multiplexing through spatial frequency-division multiplexing (sFDM). The sensor’s output is demodulated using selective local Fourier transform, which significantly reduces computational complexity by focusing only on the resonant spatial frequency components of interest. Experimental results show that the proposed 3R-FPI exhibits clear and repeatable spectral responses to inclination changes within a range of − 50° to + 50°, with linear sensitivities of 6 × 10⁻⁷a.u./° and 3 × 10⁻⁷a.u./° for Configurations I and II, respectively (R² > 0.98). The developed system further demonstrates biaxial inclination/tilt measurement capability when two 3R-FPI sensors are integrated orthogonally in a single array. The compact design, high sensitivity, and efficient frequency-domain multiplexing make the fs-laser-inscribed 3R-FPI an excellent candidate for distributed and vector inclination sensing in structural monitoring applications.

提出了一种基于飞秒激光直写的新型三反射面光纤光栅法布里-珀罗干涉仪（3R-FPI），并进行了倾角检测实验验证。传感器结构由三个短布拉格光栅组成，包括一个标准芯光栅和两个沿单模光纤精确定位的边芯光栅。边芯光栅和芯光栅的结合使得弯曲引起的不对称电场分布有效地转化为光强变化。两种3R-FPI配置精心设计了腔长，以在空间频域产生不同的、不重叠的空间频率分量，从而通过空间频分复用（sFDM）实现高效复用。传感器的输出使用选择性局部傅里叶变换解调，通过只关注感兴趣的谐振空间频率分量，大大降低了计算复杂性。实验结果表明，在- 50°到+ 50°的倾角变化范围内，3R-FPI具有清晰、可重复的光谱响应，线性灵敏度为6 × 10 - 7a.u。/°和3 × 10−7a.u。/°分别为构型I和构型II （R2 > 0.98）。当两个3R-FPI传感器在单个阵列中正交集成时，开发的系统进一步证明了双轴倾斜/倾斜测量能力。紧凑的设计，高灵敏度和高效的频域复用使fs激光内切的3R-FPI成为结构监测应用中分布式和矢量倾斜传感的优秀候选者。

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引用次数: 0

Long-distance drone classification in intracity environments via temporal single-photon detection 基于时间单光子检测的城市环境下远程无人机分类

IF 5 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2026-06-01 Epub Date: 2026-02-07 DOI: 10.1016/j.optlastec.2026.114900

Junran Guo , Tonglin Mu , Keyuan Li , Jianing Li , Ziyang Luo , Xiaodong Fan , Ye Chen , Jinquan Huang , Minjie Liu , Ruoyang Qi , Naiting Gu , Hong Cai , Lip Ket Chin , Shihai Sun

Single-photon light detection and ranging (SP-LiDAR) offers exceptional capabilities for long-range imaging or target identification, yet its high system complexity and substantial power/time consumption have hindered deployment in task-oriented applications. In this paper, we present the first experimental demonstration of long-distance drone classification beyond 5 km in a real-world intracity setting using temporal single-photon LiDAR (TSP-LiDAR). Unlike conventional approaches, TSP-LiDAR directly extracts target features from temporal histograms, eliminating the need for imaging optics and computationally intensive reconstruction algorithms. Both simulation and field results confirm that our TSP-LiDAR successfully achieves high classification accuracy under challenging conditions, including low signal-to-noise ratio (SNR) and sparse echo photon count. Specifically, in our 5 km experiments, we achieve pose and type classification accuracies of 96.11% and 98.06%, respectively, at SNRs ranging from 0.01 to 0.15 and echo photon count rates between 2∼30 kHz. Notably, the system further discriminates fine pitch variations down to approximately 1.15°. These findings underscore the potential of our TSP-LiDAR for robust, long-range classification of small aerial targets, paving the way for advanced urban surveillance and air defense applications.

单光子光探测和测距（SP-LiDAR）为远程成像或目标识别提供了卓越的能力，但其高系统复杂性和大量功耗/时间消耗阻碍了面向任务的应用的部署。在本文中，我们首次展示了在真实城市环境中使用时序单光子激光雷达（TSP-LiDAR）进行超过5公里的远程无人机分类的实验演示。与传统方法不同，TSP-LiDAR直接从时间直方图中提取目标特征，消除了对成像光学器件和计算密集型重建算法的需求。仿真和现场结果都证实，我们的TSP-LiDAR在具有挑战性的条件下，包括低信噪比（SNR）和稀疏回波光子计数，成功地实现了高分类精度。具体来说，在我们的5公里实验中，我们在信噪比为0.01至0.15，回波光子计数率为2 ~ 30 kHz的情况下，分别实现了96.11%和98.06%的姿态和类型分类准确率。值得注意的是，该系统进一步区分小至约1.15°的细微音高变化。这些发现强调了我们的TSP-LiDAR在小型空中目标的强大，远程分类方面的潜力，为先进的城市监视和防空应用铺平了道路。

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引用次数: 0

Photoelectric hybrid deep neural network based adaptive optics scheme for vortex beam in oceanic turbulence 基于光电混合深度神经网络的海洋湍流涡旋光束自适应光学方案

IF 5 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2026-06-01 Epub Date: 2026-02-13 DOI: 10.1016/j.optlastec.2026.114936

Haichao Zhan , Yang Qu , Le Wang , Shengmei Zhao

Underwater wireless optical communication (UWOC) systems are essential for underwater applications due to their superior performance, with orbital angular momentum (OAM) boosting channel capacity via mode orthogonality. However, oceanic turbulence (OT) distorts OAM-carrying vortex beams, and existing adaptive optics (AO) methods and single-type neural network approaches are limited by cost, optimization issues, or inadequate precision. In this paper, we propose a photoelectric hybrid deep neural network (PHDNN) based AO scheme to correct the distortion caused by OT to vortex beam carrying OAM. The PHDNN model is composed of diffractive deep neural network and convolutional neural network, which are trained jointly to predict the coefficients of Zernike polynomial representing OT. The phase screen reconstructed based on the Zernike coefficients is conjugated and used to eliminate OT. The proposed scheme achieves fast convergence at 25 epochs with a final loss of 0.096, low latency of 4.113s under strong OT, and robust adaptability to varying turbulence intensities. Experimental results show that it reconstructs high-quality phase screens with a peak signal-to-noise ratio up to 35.548, and significantly enhances OAM mode purity to 0.936 under strong OT, in sharp contrast to the uncorrected value of 0.024. The proposed scheme provides the benefits for the realization of the fusion of all-optical neural network and electronic neural network, and contributes to the development of UWOC system.

水下无线光通信（UWOC）系统性能优越，轨道角动量（OAM）通过模式正交性提高信道容量，是水下应用的必要条件。然而，海洋湍流（OT）会扭曲携带oam的涡旋光束，现有的自适应光学（AO）方法和单一类型的神经网络方法受到成本、优化问题或精度不足的限制。本文提出了一种基于光电混合深度神经网络（PHDNN）的AO方案，以纠正OT对携带OAM的涡旋光束造成的畸变。PHDNN模型由衍射深度神经网络和卷积神经网络组成，并对其进行联合训练来预测表示OT的Zernike多项式的系数。基于泽尼克系数重构的相位屏被共轭化并用于消除OT。该方案实现了25个epoch的快速收敛，最终损失为0.096，在强OT下延迟低至4.113s，对不同湍流强度具有较强的适应性。实验结果表明，该方法重构出高质量的相位屏，峰值信噪比高达35.548，在强OT条件下OAM模式纯度显著提高至0.936，与未校正值0.024形成鲜明对比。该方案为实现全光神经网络与电子神经网络的融合提供了有利条件，为UWOC系统的发展做出了贡献。

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引用次数: 0

Deep learning enabled single-shot 3D measurement for colorful object in fringe projection profilometry 深度学习实现了条纹投影轮廓术中彩色物体的单镜头3D测量

IF 5 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2026-06-01 Epub Date: 2026-02-06 DOI: 10.1016/j.optlastec.2026.114895

Junyi Lin, Yupeng Li, Qi Dou, Changbiao Huang, Hua Liu, Ping Lu

The composite fringe projection profilometry based on deep learning has successfully achieved high efficiency and accuracy in single-shot 3D reconstruction. However, high-quality 3D measurement for colorful objects remains a challenging task in this field. Wrapped phase jumps and phase period ambiguity caused by color are the main reasons for the challenges. To solve these problems, this paper proposes an anti-color interference single-shot 3D reconstruction method (AIS3DRM) based on Haar-like composite fringe projection (HCFP) and dual-context scale-aware network (DCSA-Net), which utilizes HCFP to better reduce the phase jump and effectively avoid the phase period ambiguity in the colorful object measurement domain, and DCSA-Net to restore the non-ideal fringe patterns caused by color mutation. The deep-learning-enabled HCFP profilometry (DHCFPP) method is adopted to implement the three-frequency four-step phase-shifting method (TFPM) efficiently and accurately. DCSA-Net is an architecture based on U-Net, which integrates Spatial Frequency Fusion Attention Blocks (SFFABs) and an Adversarial Training Framework (ATF). SFFABs dynamically weight features through parallel branches to ensure robust performance under different object color conditions. ATF further optimizes the loss function by comparing the up-sampled output with real data. Our experimental results demonstrate that the proposed method outperforms existing methods in terms of the quality of the generated phase and the integrity of the point cloud for colorful object measurement.

基于深度学习的复合条纹投影轮廓术在单镜头三维重建中取得了较高的效率和精度。然而，彩色物体的高质量三维测量仍然是该领域的一项具有挑战性的任务。包裹相位跳跃和由颜色引起的相位周期模糊是造成挑战的主要原因。针对这些问题，本文提出了一种基于haar样复合条纹投影（HCFP）和双上下文尺度感知网络（DCSA-Net）的抗颜色干扰单镜头三维重建方法（AIS3DRM），该方法利用HCFP更好地减少了彩色物体测量域中的相位跳变，有效避免了相位周期模糊，利用DCSA-Net恢复了颜色突变引起的非理想条纹图案。采用基于深度学习的HCFP轮廓术（DHCFPP）方法，高效、准确地实现了三频四步移相法（TFPM）。DCSA-Net是一种基于U-Net的体系结构，它集成了空间频率融合注意块（SFFABs）和对抗性训练框架（ATF）。SFFABs通过并行分支动态加权特征，保证了在不同物体颜色条件下的鲁棒性能。ATF通过将上采样输出与实际数据进行比较，进一步优化损失函数。实验结果表明，该方法在生成相位的质量和彩色物体测量点云的完整性方面优于现有方法。

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引用次数: 0

Ablation characteristics and material removal mechanism of Invar 36 alloy under femtosecond laser irradiation 飞秒激光辐照下Invar 36合金的烧蚀特性及材料去除机理

IF 5 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2026-06-01 Epub Date: 2026-02-06 DOI: 10.1016/j.optlastec.2026.114878

Zhenda Wang , Xiaohong Lu , Yuhang Tian , Hao Wang , Steven Y. Liang

To investigate the material removal mechanism in femtosecond laser processing of Invar 36 alloy, this paper establishes a coupled fluid–solid simulation model based on multiphysics coupling and multiscale effects. The validity of the simulation model is also verified. Using the established model, the competitive mechanisms among explosive vaporization, molten material ejection, and phase explosion during femtosecond laser ablation of Invar 36 alloy are investigated in depth. Meanwhile, the formation mechanism of laser-induced periodic surface structures (LIPSS) and the distribution characteristics of the ablation plume are analyzed. This study on the material removal mechanism in femtosecond laser processing of Invar 36 alloy provides a theoretical basis for subsequent high-quality processing of Invar 36 alloy.

为了研究飞秒激光加工Invar 36合金的材料去除机理，建立了基于多物理场耦合和多尺度效应的流固耦合仿真模型。验证了仿真模型的有效性。利用所建立的模型，对Invar 36合金飞秒激光烧蚀过程中炸药汽化、熔融物质喷射和相爆炸的竞争机理进行了深入研究。同时，分析了激光诱导周期表面结构（LIPSS）的形成机理和烧蚀羽流的分布特征。对Invar 36合金飞秒激光加工中材料去除机理的研究，为后续Invar 36合金的高质量加工提供了理论依据。

引用次数: 0

Simplified Kerr refractive index measurement in the visible range using phase object contrast imaging 使用相位物体对比成像在可见范围内简化克尔折射率测量

IF 5 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2026-06-01 Epub Date: 2026-02-06 DOI: 10.1016/j.optlastec.2026.114888

Georges Boudebs , Julien-Bilal Zinoune , Christophe Cassagne , Mihaela Chis

A streamlined method is presented for determining the nonlinear refractive index

n_{2}

using phase objects embedded in an optical imaging configuration. The approach is particularly well suited to broadband sources such as tunable optical parametric amplifiers (OPAs), which typically exhibit non-Gaussian spatial profiles and femtosecond pulses with wavelength-dependent duration. Conventional techniques such as Z-scan require precise knowledge of intensity, pulse duration, beam waist and sample position, parameters that are difficult to control in OPA-based systems. The proposed method overcomes these constraints through a two-shot comparative measurement between a reference material (e.g., fused silica) and the sample, eliminating the need for translation stages, autocorrelation diagnostics and detailed beam characterization. By referencing the nonlinear phase shift to a well-known material, the technique removes scanning and intensity-calibration requirements, ensuring broad applicability across wavelengths and sample types. Theoretical modeling and experimental validation demonstrate high sensitivity together with a substantial reduction in experimental complexity. Results show excellent agreement with established methods, confirming the reliability of the approach. This work provides a rapid and efficient route for characterizing nonlinear optical properties in situations where conventional techniques are impractical. Supplementary Materials include data-processing scripts and numerical resources to facilitate implementation and reproducibility.

提出了一种简化的方法来确定非线性折射率n2使用相位对象嵌入在一个光学成像配置。该方法特别适用于宽带光源，如可调谐光参量放大器（OPAs），它们通常表现出非高斯空间分布和波长相关持续时间的飞秒脉冲。传统的技术，如z扫描，需要精确的强度，脉冲持续时间，束腰和样品位置的知识，在基于opa的系统中难以控制的参数。该方法通过在参考材料（如熔融二氧化硅）和样品之间进行两次对比测量来克服这些限制，消除了平移阶段、自相关诊断和详细的光束表征的需要。通过参考一种众所周知的材料的非线性相移，该技术消除了扫描和强度校准要求，确保了跨波长和样品类型的广泛适用性。理论建模和实验验证表明，该方法具有较高的灵敏度，同时大大降低了实验复杂度。结果表明，该方法与已有方法非常吻合，证实了该方法的可靠性。这项工作为在传统技术无法实现的情况下表征非线性光学特性提供了一种快速有效的途径。补充材料包括数据处理脚本和数字资源，以促进实施和再现性。

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引用次数: 0

Gravity-induced distortion dynamics of molten pool and keyhole during non-horizontal dual laser beam bilateral synchronous welding for Ti-6Al-4V alloy T-joints Ti-6Al-4V合金t形接头非水平双激光束双边同步焊接过程中熔池和锁孔重力畸变动力学

IF 5 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2026-06-01 Epub Date: 2026-02-04 DOI: 10.1016/j.optlastec.2026.114815

Yanqiu Zhao , Tingyan Yan , Rui Li , Jiangfeng Wang , Chao Ma , Xiaohong Zhan

Dual laser beam bilateral synchronous welding (DLBSW) has been proven as an effective fabrication technique for Ti-6Al-4V alloy T-joints. Nevertheless, the pronounced impact of gravity deflection on fluid flow and keyhole stability in DLBSW of spatially complex curved structures must be thoroughly evaluated, given its consequential effects on porosity and fatigue life. In this paper, the thermal-fluid coupling models of Ti-6Al-4V alloy T-joints during horizontal DLBSW and Non-Horizontal DLBSW at the gravity deflection angle (θ) of 25° and 40° were respectively established. The spatiotemporal characteristics of fluid flow under diverse gravitational regimes and the dynamic evolution of the keyhole were comprehensively delineated. Additionally, the fundamental mechanism governing gravity-driven distortion of the molten pool and the resultant destabilization of the orifice under the dual-beam coupling effect was uncovered. It is revealed that gravitational deflection induces a reconfiguration of liquid metal flow from the upper molten pool, leading to diminished thermal energy delivery to the anterior wall. This, in turn, restricts the advancement of the solid/liquid interface and exacerbates thermal asymmetry. Moreover, gravitational deflection enhances bubble nucleation, impedes their removal, and compromises the liquid’s void-filling efficacy, culminating in porosity formation. These outcomes offer significant guidance for porosity suppression strategies and inform the refinement of DLBSW techniques for T-joint manufacturing.

双激光束双边同步焊接（DLBSW）是制备Ti-6Al-4V合金t型接头的有效方法。然而，考虑到重力偏转对孔隙率和疲劳寿命的影响，必须彻底评估重力偏转对空间复杂弯曲结构DLBSW中流体流动和锁孔稳定性的显著影响。建立了Ti-6Al-4V合金t型接头在重力偏转角（θ）为25°和40°时的横向和非横向DLBSW热流耦合模型。全面描绘了不同重力状态下流体流动的时空特征和锁孔的动态演化。此外，还揭示了在双光束耦合作用下，重力驱动熔池变形和导致孔板失稳的基本机理。结果表明，重力偏转引起熔池上部金属液流动的重新配置，导致前壁的热能传递减少。这反过来又限制了固/液界面的推进，加剧了热不对称。此外，重力偏转增强了气泡成核，阻碍了气泡的去除，影响了液体的充空效果，最终导致孔隙的形成。这些结果为抑制孔隙度的策略提供了重要的指导，并为t型接头制造的DLBSW技术的改进提供了信息。

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引用次数: 0

Advances in laser ablation-assisted water electrolysis for hydrogen production 激光烧蚀辅助水电解制氢研究进展

IF 5 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2026-06-01 Epub Date: 2026-02-10 DOI: 10.1016/j.optlastec.2026.114884

Jian Pu , Fang Hu , Yuan Li , Chuang Yue

In recent years, the increasing global demand for clean energy has spurred extensive research into hydrogen production via water electrolysis—a highly promising renewable technology. Electrocatalysts play a critical role in determining the efficiency and purity of this process, serving as a core component for improving overall performance. Laser ablation technology, boasting remarkable advantages like high efficiency, precision, and non-contact operation, has blazed a new route for the preparation of high-performance electrocatalysts. This technique enables the construction of micro/nano framework structures that offer abundant active sites, while allowing precise control over the composition, structure, and morphology of catalysts at the atomic level. As a result, it facilitates comprehensive enhancement of catalytic activity, stability, and electrical conductivity. This article provides a systematic review of recent advances in laser ablation for electrocatalyst preparation and offers a forward-looking perspective on future developments, aiming to serve as a valuable reference for further breakthroughs in the field.

近年来，全球对清洁能源日益增长的需求刺激了对水电解制氢的广泛研究，这是一种非常有前途的可再生技术。电催化剂在决定该工艺的效率和纯度方面起着关键作用，是提高整体性能的核心组成部分。激光烧蚀技术以其高效、精确、无接触等显著优点，为高性能电催化剂的制备开辟了一条新途径。该技术能够构建提供丰富活性位点的微/纳米框架结构，同时允许在原子水平上精确控制催化剂的组成、结构和形态。因此，它有助于全面提高催化活性，稳定性和导电性。本文系统综述了激光烧蚀制备电催化剂的最新进展，并对未来的发展进行了展望，旨在为该领域的进一步突破提供有价值的参考。

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引用次数: 0

Extended numerical monochromatization for broadband phase retrieval 宽带相位检索的扩展数值单色化

IF 5 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2026-06-01 Epub Date: 2026-02-11 DOI: 10.1016/j.optlastec.2026.114894

Zhengkang Xu , Jin Niu , Huixiang Lin , Yongjun Ma , Hao Xu , Yutong Wang , Yunsong Liang , Changjun Ke , Fucai Zhang , Xiaoshi Zhang , Jie Li , Zhongwei Fan

With the advancement of attosecond science, probing ultrafast processes at unprecedented scales has become possible, opening new frontiers in ultrafast imaging. The spectrum of ultrafast attosecond pulses typically exhibits a broad bandwidth rather than monochromatic radiation, presenting significant challenges for image reconstruction. In this study, we introduce a novel algorithm, Extended Numerical Monochromatization (ENM), which imposes a prior constraint on the solution of numerical monochromatization. This approach enables precise numerical monochromatization of broadband diffraction patterns, achieving a substantial improvement in resolution by approximately 2 times, as demonstrated in experimental results with 15% bandwidth light source. Notably, ENM maintains robust reconstruction performance even with a substantial reduction in the spectral sampling rate. The method is applicable to various broadband sources, including both continuous and discrete spectra, under the assumption of investigating non-dispersive specimens. Additionally, we introduce an improved method for constructing the key matrix in the numerical monochromatization process, resulting in a significant speedup. For example, the computation time was reduced by up to 18 times in selected cases, and the speedup increases even further as the data size grows. With its increased speed, high accuracy, and robustness, ENM provides a new perspective and powerful tool for ultrafast imaging at the attosecond scale.

随着阿秒科学的进步，以前所未有的规模探测超快过程成为可能，为超快成像开辟了新的领域。超快阿秒脉冲的光谱通常具有较宽的带宽，而不是单色辐射，这对图像重建提出了重大挑战。在本研究中，我们引入了一种新的算法，扩展数值单色化（ENM），它对数值单色化的解施加了先验约束。该方法实现了宽带衍射图案的精确数值单色化，在15%带宽光源的实验结果中，分辨率提高了约2倍。值得注意的是，即使在光谱采样率大幅降低的情况下，ENM仍然保持了强大的重建性能。在研究非色散样本的假设下，该方法适用于各种宽带源，包括连续和离散光谱。此外，我们还介绍了一种改进的方法来构造数字单色化过程中的关键矩阵，从而大大提高了速度。例如，在选定的情况下，计算时间最多减少了18倍，并且随着数据大小的增加，加速速度甚至会进一步提高。ENM具有更高的速度，高精度和鲁棒性，为阿秒级的超快成像提供了新的视角和强大的工具。

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引用次数: 0

Unsupervised Transformer-based deep learning for digital image correlation and digital volume correlation 基于无监督变压器的数字图像相关和数字体积相关深度学习

IF 5 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2026-06-01 Epub Date: 2026-02-13 DOI: 10.1016/j.optlastec.2026.114939

Haoyang He , Yifei Zhou , Yajing Zhang , Yuqi Cai , Rui Li , Yiping Liu , Liqun Tang , Taolin Sun , Zhenyu Jiang

Deep learning-based digital image correlation (DIC) has demonstrated significant advantages over traditional DIC when measuring extremely complex deformation fields. However, the performance of deep learning model depends on high-quality training dataset annotated with ground-truth displacements, which are often difficult to obtain experimentally for complex deformation. To address this limitation, we extend our previously proposed Transformer-based DIC model (DICTr) by introducing the paradigm of unsupervised learning. A spontaneous constraint termed as multi-resolution displacement gradient consistency (MrDGC) is incorporated into loss function, complementing photometric consistency. This design enables the model to learn physically plausible deformation without labeled data and unjustified assumption of displacement field smoothness in existing unsupervised DIC models. Experimental results on various kinds of speckle images show that the unsupervised DICTr can accurately measure diverse deformation fields. Furthermore, the model is extended to digital volume correlation (DVC), i.e. unsupervised DVCTr. In simulated and real examples of traction force microscopy, unsupervised DVCTr achieves high accuracy in measuring highly localized deformation and exhibits robustness to noise and artifacts in volume images, outperforming traditional iterative digital volume correlation.

在测量极其复杂的变形场时，基于深度学习的数字图像相关（DIC）显示出比传统DIC显著的优势。然而，深度学习模型的性能依赖于高质量的训练数据集，这些数据集带有地面真值位移注释，而对于复杂的变形，通常难以通过实验获得。为了解决这一限制，我们通过引入无监督学习范式扩展了之前提出的基于变压器的DIC模型（DICTr）。一个自发约束称为多分辨率位移梯度一致性（MrDGC）被纳入损失函数，补充光度一致性。这种设计使模型能够在没有标记数据和现有无监督DIC模型中不合理的位移场平滑假设的情况下学习物理上合理的变形。在各种散斑图像上的实验结果表明，无监督的dicr可以准确地测量各种形变场。进一步，将该模型推广到数字体积相关（DVC），即无监督DVCTr。在引力显微镜的模拟和真实示例中，无监督DVCTr在测量高度局部化变形方面实现了高精度，并且在体积图像中表现出对噪声和伪影的鲁棒性，优于传统的迭代数字体积相关。

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引用次数: 0