Optics and Lasers in Engineering最新文献_第5页

Evolution of fractional vortices through intensity autocorrelation of scattered speckle patterns 基于散斑模式强度自相关的分数涡演化

IF 3.7 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2026-01-22 DOI: 10.1016/j.optlaseng.2026.109637

MD. Haider Ansari , Velagala Ganesh , Sakshi Choudhary , Ravi Kumar , Shashi Prabhakar , Salla Gangi Reddy

Measuring the topological charge (TC) of optical vortices is crucial for advancing applications in areas such as optical communication and quantum information processing. Although various interferometric and non-interferometric techniques have been developed for coherent and partially coherent beams, most of these methods are ineffective for fractional-vortex beams, especially when the beam gets perturbed. In this work, we propose and experimentally demonstrate a simple, non-interferometric technique based on autocorrelation for assessing and quantitatively measuring the TC of fractional vortex beams. We generated fractional optical vortex beams using computer-generated fork-shaped holograms and then obtained the corresponding random optical patterns after scattering through a rough surface. The autocorrelation rings of random patterns provide the TC of fractional vortex beams, and the asymmetry gradually becomes symmetric as the TC approaches an integer value. Additionally, by examining the divergence of the first dark ring with respect to propagation distance, we can quantitatively estimate the fractional TC. The measured divergence closely matches theoretical results, achieving an accuracy of over 98 %. The proposed method eliminates the need for phase retrieval, coherence modulation, or interferometry, providing a practical and robust solution for measuring fractional TCs, even in the presence of perturbations such as scattering and mild atmospheric turbulence, which are common in free-space optical communication systems.

测量光涡旋的拓扑电荷（TC）对于推进光通信和量子信息处理等领域的应用至关重要。尽管针对相干光束和部分相干光束已经开发了各种干涉和非干涉技术，但这些方法大多对分数涡光束无效，特别是当光束受到扰动时。在这项工作中，我们提出并实验证明了一种简单的、基于自相关的非干涉技术，用于评估和定量测量分数涡旋光束的TC。利用计算机生成的叉形全息图生成分数阶光学涡旋光束，通过粗糙表面散射后得到相应的随机光学图样。随机图样的自相关环提供分数涡旋光束的TC，当TC接近整数值时，不对称逐渐变成对称。此外，通过检查第一暗环的散度与传播距离的关系，我们可以定量地估计分数TC。测量的散度与理论结果非常吻合，精度超过98%。所提出的方法消除了相位恢复、相干调制或干涉测量的需要，为测量分数阶tc提供了一种实用而稳健的解决方案，即使存在散射和轻微大气湍流等扰动，这在自由空间光通信系统中很常见。

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引用次数: 0

High efficiency Raman microscopic imaging based on a dispersion-interference hybrid spectrometer 基于色散干涉混合光谱仪的高效拉曼显微成像

IF 3.7 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2026-01-20 DOI: 10.1016/j.optlaseng.2026.109624

Huitong Huang , Xin Meng , Xiaohong Jiang , Ao Wang , Yixuan Xu , Zhibiao Liu , Yixuan Liu , Jianxin Li

Optical throughput and spectral resolution are two critical parameters for achieving rapid and accurate Raman microscopic imaging. However, conventional methods often face a trade-off between these two performances. In response to this limitation, this work proposes a high-efficiency Raman microscopic imaging system based on a dispersion-interference hybrid spectroscopic architecture. By integrating Amici prisms into a Sagnac interferometer, the system enables spectral shearing control without the need for an entrance slit, achieving both high throughput and good spectral resolution. Using a 785 nm laser, the system was evaluated on Nd: Y₃Al₅O₁₂ ceramics, fluorite crystals, and SERS-enhanced 4-aminothiophenol samples on a gold substrate, achieving a point spectral resolution of 10 cm⁻¹ and a full width at half maximum (FWHM) resolution of 25 cm⁻¹. Combined with a 1024 × 1024 pixel EMCCD camera, the system supports area imaging and employs a one-dimensional push-broom scanning strategy to efficiently acquire the entire field of view, significantly improving imaging speed compared to conventional point-by-point scanning methods. Experimental results demonstrate that the system offers high throughput, high resolution, and rapid Raman hyperspectral imaging capabilities, with potential applications in material analysis, biological detection, and chemical imaging.

光学通量和光谱分辨率是实现快速、准确拉曼显微成像的两个关键参数。然而，传统方法经常面临这两种性能之间的权衡。针对这一局限性，本文提出了一种基于色散-干涉混合光谱结构的高效拉曼显微成像系统。通过将Amici棱镜集成到Sagnac干涉仪中，该系统无需入口狭缝即可实现光谱剪切控制，从而实现高通量和良好的光谱分辨率。使用785 nm激光，在金衬底上对Nd: Y₃Al₅O₁₂陶瓷，萤石晶体和sers增强的4-氨基噻吩样品进行了评估，获得了10 cm⁻¹的点光谱分辨率和25 cm⁻¹的半宽（FWHM）分辨率。该系统配合1024 × 1024像素的EMCCD摄像头，支持区域成像，采用一维推扫帚扫描策略，有效获取整个视场，与传统逐点扫描方式相比，成像速度显著提高。实验结果表明，该系统具有高通量、高分辨率和快速的拉曼高光谱成像能力，在材料分析、生物检测和化学成像方面具有潜在的应用前景。

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引用次数: 0

64 dB gain Yb-doped fiber amplifier for small-signal lasers based on tandem pump cavity 基于串列泵浦腔的64 dB增益掺镱小信号激光器放大器

IF 3.7 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2026-01-20 DOI: 10.1016/j.optlaseng.2026.109632

Wei Gao , Pei Ju , Yanpeng Zhang , Haoyu Wang , Zhaohui Li , Zhe Li , Pei Huang , Aifeng He , Qi Gao , Wenhui Fan

We propose a high-gain fiber amplifier based on a tandem pump cavity tailored for small-signal lasers. The small-signal laser can obtain high gain when passing through the tandem pump cavity and is then continuously amplified by the tandem core-pumping process. In our experimental setup, a 50 µW signal laser is amplified to 128.5 W, achieving a maximum gain of 64 dB, surpassing conventional fiber amplifier capabilities. This approach offers a promising pathway toward compact, reliable, and cost-effective high-gain fiber amplifiers.

我们提出了一种基于串联泵浦腔的高增益光纤放大器，为小信号激光器量身定制。小信号激光通过串列泵浦腔获得高增益，然后通过串列抽芯过程不断放大。在我们的实验设置中，50 μ W的信号激光被放大到128.5 W，实现64 dB的最大增益，超过了传统光纤放大器的能力。这种方法为实现紧凑、可靠、经济高效的高增益光纤放大器提供了一条有前途的途径。

引用次数: 0

Single-shot high-dynamic-range 3-D measurement via color coding and spatial-frequency domain learning 基于颜色编码和空间频域学习的单镜头高动态范围三维测量

IF 3.7 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2026-01-20 DOI: 10.1016/j.optlaseng.2026.109633

Jing Xin , Fuqian Li , Qican Zhang , Yajun Wang , Haojie Wei

In optical three-dimensional (3D) measurement techniques, fringe projection is one of the most reliable techniques for recovering the shape of objects. One challenge of the fringe projection is the measurement of high dynamic range (HDR) surfaces. Current non-learning-based and learning-based methods typically require acquiring multiple phase-shifting (PS) fringe patterns to achieve high-precision HDR 3-D reconstruction, which leads to the limited measurement efficiency. To overcome this limitation, a single-shot HDR method (PI-SSM) based on color coding and spatial-frequency domain learning is proposed. There are two key contributions in this work. First, the physics-informed single-shot measurement framework which integrates hardware modulation and deep-learning algorithms in a novel way for HDR 3-D reconstruction is proposed. Specially, a color coding strategy is utilized to realize single-shot measurement, which acquires three fringe patterns simultaneously. Furthermore, by the network training, the color crosstalk problem caused by color coding can be suppressed, and the damaged phase of the HDR surfaces can be repaired. Second, to enhance fringe quality under severe HDR degradation, a spatial-frequency domain fringe enhancement network (SFENet) is specifically designed. SFENet restores degraded fringe by jointly modeling local noise-induced distortions in the spatial domain and enforcing global periodic consistency in the frequency domain. And a joint spatial-frequency loss further improves fringe enhancement quality and phase accuracy. Experiments demonstrate that the proposed PI-SSM method enables more accurate and efficient single-shot phase retrieval, exhibiting its excellent generalization to various unseen HDR surfaces.

在光学三维测量技术中，条纹投影是恢复物体形状最可靠的技术之一。条纹投影的一个挑战是测量高动态范围（HDR）表面。目前基于非学习和基于学习的方法通常需要获取多个相移（PS）条纹图来实现高精度的HDR三维重建，这导致测量效率有限。为了克服这一局限性，提出了一种基于颜色编码和空频域学习的单镜头HDR方法（PI-SSM）。在这项工作中有两个关键的贡献。首先，提出了基于物理信息的单镜头测量框架，该框架将硬件调制和深度学习算法相结合，以一种新颖的方式用于HDR三维重建。特别地，利用颜色编码策略实现了单镜头测量，同时获得了三种条纹图案。此外，通过网络训练，可以抑制颜色编码引起的颜色串扰问题，修复HDR表面的损坏相位。其次，为提高HDR严重退化情况下的条纹质量，设计了空间频域条纹增强网络（SFENet）。SFENet通过在空间域中模拟局部噪声引起的畸变，在频率域中增强全局周期一致性来恢复退化条纹。联合空间频率损失进一步提高了条纹增强质量和相位精度。实验表明，PI-SSM方法能够更准确、高效地进行单次相位检索，对各种未见的HDR表面具有良好的泛化能力。

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引用次数: 0

Single-photon lidar system and multiscale optimization algorithm for extreme SBR 极端SBR单光子激光雷达系统及多尺度优化算法

IF 3.7 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2026-01-20 DOI: 10.1016/j.optlaseng.2026.109629

Jinfeng Xu , Qingsheng Xue , Fengqin Lu , Junhong Song , Xing Li

Single-photon counting lidar enables highly sensitive imaging by detecting extremely weak photon returns, but reconstructing reliable depth and reflectance from sparse photon data under extreme low signal-to-background ratio (SBR) conditions remains challenging. We propose a reflectance-guided multi-scale joint optimization framework built on the Sparse Poisson Intensity Reconstruction Algorithm (SPIRAL-TAP), which achieves collaborative reconstruction of reflectance and depth, and thus avoids the edge blurring and structural inconsistencies often observed when reflectance and depth are reconstructed independently. In the depth update, reflectance-weighted guidance is introduced to improve reconstruction quality. Compared with several signal reconstruction algorithms, the proposed algorithm achieves high-quality 3D reconstruction with a reflectance root mean square error (RMSE) of 0.11 and depth RMSE 0.2 m at an extreme SBR of 0.04, representing a 48% reduction relative to the single-scale SPIRAL-TAP method. The effectiveness and generality of the framework are validated on publicly available sparse photon datasets. The experimental results demonstrate that the method significantly improves reconstruction accuracy while preserving fine spatial details, and provides a practical solution for 3D imaging under low-SBR single-photon lidar conditions.

单光子计数激光雷达通过检测极弱的光子返回来实现高灵敏度成像，但在极低信本比（SBR）条件下，从稀疏光子数据重建可靠的深度和反射率仍然具有挑战性。在稀疏泊松强度重建算法（SPIRAL-TAP）的基础上，提出了一种基于反射率引导的多尺度联合优化框架，实现了反射率和深度的协同重建，避免了反射率和深度单独重建时经常出现的边缘模糊和结构不一致等问题。在深度更新中，引入了反射率加权制导，提高了重建质量。与几种信号重建算法相比，该算法实现了高质量的三维重建，反射率均方根误差（RMSE）为0.11，深度RMSE为0.2 m， SBR极值为0.04，相对于单尺度SPIRAL-TAP方法降低了48%。在公开的稀疏光子数据集上验证了该框架的有效性和通用性。实验结果表明，该方法在保持良好空间细节的同时，显著提高了重建精度，为低sbr单光子激光雷达条件下的三维成像提供了一种实用的解决方案。

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引用次数: 0

Automatic refocusing method for nanoscale topographic measurement by optical coherence tomography 光学相干层析成像纳米尺度地形测量的自动重聚焦方法

IF 3.7 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2026-01-19 DOI: 10.1016/j.optlaseng.2026.109636

Di Yang , Zhuoqun Yuan , Xinyi Li , Yapeng Sun , Qiunan Yang , Yanmei Liang

Surface topography influences the functional properties of material interfaces, including optical, mechanical, and biological properties. Nanoscale topographic measurement is essential for precision manufacturing and surface defect analysis. While optical coherence tomography (OCT) offers a millimeter-scale field of view without mechanical scanning, its effective topographic measurement range is limited by a shallow depth of focus. Defocusing could degrade the accuracy and resolution of the topographic measurement. To address this limitation, we proposed an automatic refocusing method for nanoscale topographic measurement with a large axial measurement range. By analyzing the frequency of topographic information, we identified a robust frequency feature, termed averaging low-frequency intensity, that enables precise estimation of defocus distance. Based on this, a refocusing algorithm is developed to automatically determine and correct defocus without additional hardware. Experimental results of a USAF resolution target demonstrated that the proposed method can extend the axial measurement range up to six times the depth of focus while preserving lateral resolution and suppressing side lobes. Further validation on scratched glass showed that the method can accurately recover nanoscale surface damage at a 6 times defocus position. Finally, the measurement results of the metal with a rough surface demonstrated that the proposed method can recover the nanoscale topography of complex samples under defocus. This approach offers a promising solution for high-precision surface profiling in industrial inspection and biomedical imaging.

表面形貌影响材料界面的功能特性，包括光学、机械和生物特性。纳米尺度的形貌测量是精密制造和表面缺陷分析的必要条件。虽然光学相干层析成像（OCT）提供了毫米尺度的视场，而无需机械扫描，但其有效的地形测量范围受到浅焦深度的限制。离焦会降低地形测量的精度和分辨率。为了解决这一问题，我们提出了一种用于大轴向测量范围的纳米尺度地形测量的自动重聚焦方法。通过分析地形信息的频率，我们确定了一个鲁棒的频率特征，称为平均低频强度，可以精确估计离焦距离。在此基础上，提出了一种无需额外硬件即可自动确定和校正离焦的重聚焦算法。USAF分辨率目标的实验结果表明，该方法可以将轴向测量范围扩展到6倍焦深，同时保持横向分辨率和抑制侧瓣。对划痕玻璃的进一步验证表明，该方法可以准确地恢复6倍离焦位置的纳米级表面损伤。最后，对粗糙表面金属的测量结果表明，该方法可以恢复复杂样品在离焦下的纳米级形貌。这种方法为工业检测和生物医学成像中的高精度表面轮廓分析提供了一种有前途的解决方案。

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引用次数: 0

A criterion for assessing spatial resolution in digital image correlation: Applications to conventional, Gaussian-weighted, and deep learning-based methods 评估数字图像相关中空间分辨率的标准：在传统、高斯加权和基于深度学习方法中的应用

IF 3.7 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2026-01-19 DOI: 10.1016/j.optlaseng.2026.109631

Zhichen Tang , Canyu Zhu , Guanyu Cheng , Shihai Lan , Yong Su

Accurate characterization of spatial resolution is essential for assessing the performance of digital image correlation (DIC) methods. Inspired by the classical Rayleigh criterion, this study considers a double-step displacement field and defines the spatial resolution as the separation at which two adjacent displacement discontinuities can just be resolved in the measured strain field. Based on this definition, theoretical models are developed to quantify the spatial resolution. For conventional DIC with a subset size of

2 M + 1

, the spatial resolution for the first-order shape function is approximately

2 M + 2

, while that for the second-order shape function is about

0.66 (2 M + 1)

. For Gaussian-weighted DIC with a weighting radius of R, the spatial resolution is approximately 2R for the first-order shape function and 1.53R for the second-order shape function. The proposed criterion is further applied to deep learning-based DIC methods (e.g., U-DICNet, DICTr, and USDICNet) to demonstrate its universality. In summary, this work establishes a physically grounded and quantitatively reliable framework for evaluating spatial resolution in conventional, weighted, and learning-based DIC methods, with potential applications in performance assessment, algorithm optimization, and parameter selection.

准确表征空间分辨率是评估数字图像相关（DIC）方法性能的关键。受经典瑞利准则的启发，本研究考虑双步位移场，并将空间分辨率定义为在测量应变场中两个相邻位移不连续点可以被解析的分离点。在此基础上，建立了量化空间分辨率的理论模型。对于子集大小为2M+1的常规DIC，一阶形状函数的空间分辨率约为2M+2，而二阶形状函数的空间分辨率约为0.66（2M+1）。对于加权半径为R的高斯加权DIC，一阶形状函数的空间分辨率约为2R，二阶形状函数的空间分辨率约为1.53R。提出的标准进一步应用于基于深度学习的DIC方法（如U-DICNet、dicr和USDICNet），以证明其通用性。总之，本研究为传统、加权和基于学习的DIC方法的空间分辨率评估建立了一个物理基础和定量可靠的框架，在性能评估、算法优化和参数选择方面具有潜在的应用前景。

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引用次数: 0

Polarization image fusion via analytical attention heads: A multi-scale feature integration framework 基于分析注意头的偏振图像融合：一种多尺度特征融合框架

IF 3.7 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2026-01-19 DOI: 10.1016/j.optlaseng.2026.109628

Junzhuo Zhou , Jun Zou , Ye Qiu , Zhihe Liu , Jia Hao , Wenli Li , Yiting Yu

Polarization imaging shows great potential for defect detection on highly reflective and low-contrast industrial surfaces. However, existing image fusion algorithms struggle to address the challenges of feature conflicts and polarization noise interference during the polarization fusion process. This paper proposes a polarization image fusion method based on analytical attention heads, aiming to integrate complementary information from different sources while enhancing the prominent features of the main source and suppressing polarization noise. The innovations of this paper are: 1) designing analytical attention heads based on mathematical principles to extract low-level image features such as gradients, textures, information, semantics, and noise; 2) detecting and enhancing prominent features in the main source image to solve the problem of feature loss caused by conflicting feature fusion from different sources; 3) detecting noisy regions in polarization image and reducing their fusion weights to avoid interference from polarization noise. We evaluated our method on both a self-built polarization image dataset and public datasets, and the results demonstrate the advanced nature of our approach. The source code and datasets are publicly available at: https://github.com/FiredTable/DeepFusion.

偏振成像在高反射和低对比度的工业表面上显示出巨大的缺陷检测潜力。然而，现有的图像融合算法难以解决极化融合过程中的特征冲突和极化噪声干扰问题。本文提出了一种基于解析注意头的偏振图像融合方法，旨在融合不同源的互补信息，同时增强主源的突出特征，抑制偏振噪声。本文的创新点在于：1)基于数学原理设计分析性注意头，提取图像的梯度、纹理、信息、语义和噪声等底层特征；2)检测并增强主源图像中的突出特征，解决不同源特征融合冲突导致的特征丢失问题；3)检测极化图像中的噪声区域，降低其融合权，避免极化噪声的干扰。我们在自建偏振图像数据集和公共数据集上对我们的方法进行了评估，结果证明了我们方法的先进性。源代码和数据集可以在：https://github.com/FiredTable/DeepFusion上公开获取。

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引用次数: 0

Dynamic opto-mechanical integrated modeling and simulation of high-resolution space telescopes 高分辨率空间望远镜动态光机集成建模与仿真

IF 3.7 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2026-01-19 DOI: 10.1016/j.optlaseng.2026.109626

Rifan Chen , Zongxuan Li , Shuping Tao , Qing Luo , Youhan Peng , Shuhui Ren , Zhiyuan Gu

To quantitatively evaluate the temporal variations of on-orbit imaging quality of space telescopes under dynamic disturbances, this study first establishes the structural dynamics state-space model of the telescope and validates its accuracy through comparative analysis with traditional finite element methods. The results demonstrate that the mean relative errors are 0.96 % for frequency response analysis and 1.22 % for transient response analysis. Subsequently, the instantaneous rigid-body displacements of the mirror surfaces are fitted based on the transient response results, with the mean relative error between the fitting results and those from the Sigfit being <2 %, thereby validating the accuracy of the dynamic response solving and rigid-body displacement fitting. Then, the offset of the image point is used to describe the dynamic LOS error of the optical system. Based on the opto-mechanical coupled ray-tracing theory, real-time reconstruction of the opto-mechanical system and ray-tracing analysis are performed, revealing that the maximum relative displacement of image points during imaging is 0.53 μm (<1/6 of the pixel). Quantitative assessment reveals that the mean relative errors for image point offsets in the X and Y directions compared with Zemax simulation are 2.53 % and 3.14 %, respectively. Furthermore, the edge method was used to calculate the MTF of the imaging system under the sole influence of micro-vibrations, which was 0.9833@143 lp/mm. This indicates that the actual impact of micro-vibrations on the overall imaging quality of the system is small. The developed framework enables accurate micro-vibration simulation and provides theoretical guidance for the optimization of vibration isolation of space telescopes.

为了定量评价空间望远镜在轨成像质量在动力扰动下的时间变化，本研究首先建立了空间望远镜的结构动力学状态空间模型，并通过与传统有限元方法的对比分析验证了模型的准确性。结果表明，频率响应分析的平均相对误差为0.96%，瞬态响应分析的平均相对误差为1.22%。随后，根据瞬态响应结果拟合镜面的瞬时刚体位移，拟合结果与Sigfit拟合结果的平均相对误差为2%，从而验证了动态响应求解和刚体位移拟合的准确性。然后，利用像点的偏移量来描述光学系统的动态LOS误差。基于光机耦合光线追迹理论，对光机系统进行实时重建和光线追迹分析，发现成像过程中图像点的最大相对位移为0.53 μm （<；1/6像素）。定量评估表明，与Zemax模拟相比，X和Y方向图像点偏移的平均相对误差分别为2.53%和3.14%。利用边缘法计算了单微振动影响下成像系统的MTF，其MTF为0.9833@143 lp/mm。这表明微振动对系统整体成像质量的实际影响很小。该框架能够实现精确的微振动仿真，为空间望远镜的隔振优化提供理论指导。

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引用次数: 0

Doubled field-of-view of point diffraction interferometer with a grating outside the Fourier plane 傅立叶平面外有光栅的点衍射干涉仪的双视场

IF 3.7 2区工程技术 Q2 OPTICS

Optics and Lasers in Engineering

Pub Date : 2026-01-16 DOI: 10.1016/j.optlaseng.2026.109604

Jianchao Guo , Mingguang Shan , Zhi Zhong , Bin Liu , Lei Yu , Lijing Wang , Lei Liu

The point diffraction interferometer (PDI) is a promising quantitative phase imaging (QPI) method, which has the advantages of compactness and stability. However, the field-of-view (FOV) of PDI is always compromised between the size of the sensor and the magnification. To solve this problem, a PDI with doubled FOV is set up by a grating placed outside the Fourier plane in a 4f system, which has a simple optical setup and larger FOV without decreasing the magnification. First, a 4f system is built up by two Lens. Then, a grating is placed outside the Fourier plane of the 4f system, while a hole array is placed exactly at the Fourier plane. The grating diffracts the object beam into several duplicates with relative offsets along its periodicity, each of which carries a different region of the object. The hole array comprises one pinhole and two large holes. One of ±1 diffraction orders is low-pass filtering by the pinhole to form the reference beam, while the other one of ±1 diffraction orders and 0th diffraction order pass through the large holes and act as the object beams with different FOV. The image sensor is placed at an overlapping area of two FOVs, which enables two distinct regions of the object to be captured simultaneously in a single shot. Moreover, induced by the different angles between the reference beam and the object beams, object beams with different FOVs have different spatial carrier frequencies in the multiplexed interferogram. To avoid crosstalk between the object beams, two object beams are modulated into orthogonal polarization states to avoid interference. The validity and feasibility of this PDI are verified by conducting experiments on a 1951USAF resolution plate, a bee wing, and onion epidermal cells. The experimental results show that this proposed PDI can double FOV without sacrificing image quality, which demonstrates various future applications in microscopic imaging and optical metrology.

点衍射干涉仪（PDI）具有结构紧凑、稳定性好等优点，是一种很有前途的定量相位成像方法。然而，PDI的视场（FOV）总是在传感器尺寸和放大倍率之间折衷。为了解决这个问题，在4f系统中，通过在傅里叶平面外放置光栅来实现双视场的PDI，该系统具有简单的光学设置和更大的视场而不降低放大倍率。首先，一个4f系统由两个Lens组成。然后，在4f系统的傅里叶平面外放置一个光栅，而在傅里叶平面上恰好放置一个孔阵列。光栅沿其周期将物体光束衍射成具有相对偏移量的几个副本，每个副本携带物体的不同区域。孔阵列包括一个针孔和两个大孔。其中±1衍射阶通过针孔低通滤波形成参考光束，而±1衍射阶和第0衍射阶通过大孔作为不同视场的目标光束。图像传感器被放置在两个fov的重叠区域，这使得物体的两个不同区域可以在一次拍摄中同时被捕获。此外，受参考光束与目标光束夹角不同的影响，不同视场的目标光束在复用干涉图中具有不同的空间载频。为了避免目标光束之间的串扰，将两个目标光束调制成正交偏振态以避免干扰。通过在1951USAF分辨率板、蜜蜂翅膀和洋葱表皮细胞上进行实验，验证了该PDI的有效性和可行性。实验结果表明，该方法可以在不牺牲图像质量的情况下实现双倍视场，在显微成像和光学计量中具有广泛的应用前景。

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引用次数: 0