Lu Zhang , Yuting Wang , Tong Liu , Huijun Wang , Bingwen Zhang , Yuxiang Huang , Chen Fan , Zewen Yang , Hong Zhao , Li Yuan , Cuiping Yao , Lifang Tian
{"title":"Hessian intensity-only diffraction tomography for 3D refractive index reconstruction","authors":"Lu Zhang , Yuting Wang , Tong Liu , Huijun Wang , Bingwen Zhang , Yuxiang Huang , Chen Fan , Zewen Yang , Hong Zhao , Li Yuan , Cuiping Yao , Lifang Tian","doi":"10.1016/j.optlaseng.2025.109285","DOIUrl":"10.1016/j.optlaseng.2025.109285","url":null,"abstract":"<div><div>Intensity-only optical diffraction tomography (IDT) is a recently developed label-free three-dimensional (3D) refractive index (RI) quantitative imaging technique for biomedical fields. However, its inherent missing cone problem and reliance solely on intensity measurement led to underestimation of RI in 3D space and elongation of RI distribution along the optical axis. In this paper, we propose Hessian Intensity-only diffraction tomography (Hessian-IDT) method to optimize the missing cone problem and the limitations associated with intensity-only measurements. Hessian-IDT iteratively reconstructs the scattering potential of the sample using the 3D extension of the Fourier Ptychographic Microscopy (FPM) algorithm, and Hessian regularization and non-negative constraints are added to the iterative process using the Split Bregman algorithm by incorporating prior knowledge about sample smoothness and positivity. Cell simulation and complex sample simulation demonstrate that Hessian-IDT yields higher-quality 3D RI reconstructions compared to existing IDT methods. Our experiments using microspheres, label-free cheek cells, and transverse sections of Hydra support this conclusion. Hessian-IDT shows potential for advancing applications in biomedical fields.</div></div>","PeriodicalId":49719,"journal":{"name":"Optics and Lasers in Engineering","volume":"195 ","pages":"Article 109285"},"PeriodicalIF":3.7,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144895519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chenbo Zhang , Guangjian Wang , Mingde Zhang , Guangxing Song
{"title":"Dual-parameter linear imaging model based automatic high dynamic range 3D measurement and multi-weight phase fusion method","authors":"Chenbo Zhang , Guangjian Wang , Mingde Zhang , Guangxing Song","doi":"10.1016/j.optlaseng.2025.109289","DOIUrl":"10.1016/j.optlaseng.2025.109289","url":null,"abstract":"<div><div>Although Fringe Projection Profilometry (FPP) has emerged as an efficient 3D measurement technique, achieving automatic High Dynamic Range (HDR) measurements remains challenging. Traditional automatic HDR methods are limited by the nonlinear relationship between projector radiance and current, solely relying on exposure time adjustment, which restricts the achievable dynamic range. Moreover, the traditional approach of selecting the brightest unsaturated phase has proven insufficient for improving measurement accuracy. This paper presents a dual-parameter linear imaging model to address these limitations. The proposed model introduces a reference current and implements a current ratio factor, enabling linear control of both exposure time and projector radiance. This approach overcomes the limitations of single-parameter exposure adjustments and nonlinear radiation response, thereby substantially expanding the dynamic range of the FPP system. We propose an automatic method for computing optimal exposure sequences that eliminates the need for surface reflectance calculations, thus enhancing computational efficiency. Furthermore, we develop a multi-weight phase fusion method to improve measurement accuracy. Experimental results demonstrate the effectiveness of our proposed method in automatic HDR object measurement.</div></div>","PeriodicalId":49719,"journal":{"name":"Optics and Lasers in Engineering","volume":"195 ","pages":"Article 109289"},"PeriodicalIF":3.7,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144895520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hyun Jun Kim , Chur Kim , Wonju Lee , Jihyeon Noh , Youngjin Choi , Changwon Lim
{"title":"Non-contact rheological assessment of hydrogels using deep learning and laser speckle imaging","authors":"Hyun Jun Kim , Chur Kim , Wonju Lee , Jihyeon Noh , Youngjin Choi , Changwon Lim","doi":"10.1016/j.optlaseng.2025.109286","DOIUrl":"10.1016/j.optlaseng.2025.109286","url":null,"abstract":"<div><div>In this study, deep learning techniques are explored to derive the viscoelastic properties of samples from time series speckle image data obtained through laser speckle imaging. Rheological properties are inferred from the speckle patterns generated by the interaction between coherent light and the microstructure of the material. For samples with different viscoelastic modulus, corresponding temporal and spatial variations in speckle patterns are observed. In this paper, deep learning models including 3DCNN, CNN-LSTM, ConvLSTM, and SwinLSTM were implemented to predict viscoelasticity levels from laser speckle images of different hydrogel samples and extract both spatial and temporal features from the data. These models were trained to predict the viscoelastic modulus of hydrogel samples and validated with mechanical measurements. Comparative performance analysis between models showed superior results in a multi-task training using CNN-LSTM models on laser speckle imaging data. This study suggested that well-designed deep learning models can improve the accuracy and efficiency of laser speckle imaging-based rheological measurements, offering significant potential for non-invasive, real-time assessment of mechanical properties of biological tissues and soft materials.</div></div>","PeriodicalId":49719,"journal":{"name":"Optics and Lasers in Engineering","volume":"195 ","pages":"Article 109286"},"PeriodicalIF":3.7,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144889526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maria J. Lopera , René Restrepo , Yunfeng Nie , Heidi Ottevaere , Carlos Trujillo
{"title":"Logarithmic dynamic range for improved digital lensless holographic microscopy reconstructions","authors":"Maria J. Lopera , René Restrepo , Yunfeng Nie , Heidi Ottevaere , Carlos Trujillo","doi":"10.1016/j.optlaseng.2025.109292","DOIUrl":"10.1016/j.optlaseng.2025.109292","url":null,"abstract":"<div><div>Under sub-optimal illumination conditions, DLHM often struggles to capture useful holographic information across the full sensor area. This is especially true when using relatively large, spatially extended point sources (≥ 5 µm) or very short working distances (< 10 mm). In such cases, the recorded holograms typically show useful detail only in a small, brightly illuminated central region. Since these conditions are common in practical applications, numerical preprocessing becomes essential. It can substantially improve the quality of the reconstructed wave-fields. This work proposes a hardware-free, single-frame preprocessing method called Logarithmic Dynamic Range (<em>LogDR</em>). It redistributes the recorded irradiance onto a logarithmic scale and then applies local tone mapping. This approach flattens the characteristic Gaussian illumination envelope in DLHM without introducing artifacts. Initial validation with eight illumination-limited holograms of a USAF-1951 target shows that the proposed <em>LogDR</em> method increases the effective field of view by about 13 % and improves the smallest resolvable feature from 3.10 µm to 1.95 µm while reducing background phase noise by four-fold. Compared with other methods, <em>LogDR</em> delivers the best trade-off between field of view, lateral resolution and phase contrast. A biological demonstration on a buccal-mucus smear further reveals peripheral protein aggregates and sub-cellular details that remain hidden in conventional reconstructions. Because <em>LogDR</em> operates without additional exposures, optics or machine-learning models, it offers an immediately deployable enhancement for portable or point-of-care DLHM systems, enabling wider contextual imaging and finer structural analysis under compromised illumination conditions.</div></div>","PeriodicalId":49719,"journal":{"name":"Optics and Lasers in Engineering","volume":"195 ","pages":"Article 109292"},"PeriodicalIF":3.7,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144889525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tomasz Kozacki, Moncy Sajeev Idicula, Maksymilian Chlipala, Dawid Ciesielski, Artur Szawerdak, Juan Martinez-Carranza
{"title":"Ultra-wide-angle holographic near-eye display with spherical illumination","authors":"Tomasz Kozacki, Moncy Sajeev Idicula, Maksymilian Chlipala, Dawid Ciesielski, Artur Szawerdak, Juan Martinez-Carranza","doi":"10.1016/j.optlaseng.2025.109280","DOIUrl":"10.1016/j.optlaseng.2025.109280","url":null,"abstract":"<div><div>This work develops an accurate and efficient computer generation hologram (CGH) method that supports a wide-angle field of view (FoV) or ultra-wide-angle FoV using spherical illumination. The method calculates the CGH in the frequency domain, which means that 3D object geometry information is updated in the frequency domain only for the frequency range of an object point sub-hologram. The bandwidths of these sub-holograms are shown to be narrow, providing CGH with efficient computation. Derived equations show that CGH with spherical illumination generates an image with highly inhomogeneous and highly anisotropic resolution, which depends on the size of the sub-hologram that is a function of illumination sphericity and the field coordinate. Two versions of the CGH algorithm are developed: one allowing a maximum doubling the native FoV and the second allowing a larger expansion of FoV. Finally, the spherical illumination method is shown to improve the performance of a color display. It is shown that it equalizes the FoVs of RGB holograms. The work is illustrated with experiments and simulations; the experiment shows the increase of FoV from 14.7° × 31.5° to 65.7° × 51.2°, and the simulation from 29° × 29° to 60° × 97.2°</div></div>","PeriodicalId":49719,"journal":{"name":"Optics and Lasers in Engineering","volume":"195 ","pages":"Article 109280"},"PeriodicalIF":3.7,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144889524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yan Wang , Zihao Yu , Wenhui Li , Yinghuai Dong , Xiaoming Yin , Zhongpeng Zheng , Jingyu Yin , Zhiqiang Fu
{"title":"Improving surface morphology and wettability of laser-ablated aluminum via ultrasonic vibration","authors":"Yan Wang , Zihao Yu , Wenhui Li , Yinghuai Dong , Xiaoming Yin , Zhongpeng Zheng , Jingyu Yin , Zhiqiang Fu","doi":"10.1016/j.optlaseng.2025.109284","DOIUrl":"10.1016/j.optlaseng.2025.109284","url":null,"abstract":"<div><div>Utilizing ultrasonic vibration to modify laser path morphology and reconstruct surface microstructure. The impact of ultrasonic vibration on laser processing of functional surfaces has been thoroughly investigated, Micro and nanostructures were generated on a 1 mm thick aluminum substrate using an ultrasonic-assisted nanosecond pulse laser with a grid pattern scanning method, The input variables of the investigated process include laser scanning speed, ultrasonic vibration amplitude, and ultrasonic vibration frequency. The results showed that the ravine width of laser ablation increased by 50 % with the application of ultrasonic vibration, which caused the efficiency of ultrasonic assisted laser processing (UALP) increased by 7.19 % compared with normal laser processing (NLP). The addition of ultrasonic vibration resulted in elongated laser craters and recast layers oriented in the direction of the vibration, forming elliptical shapes. and became \"elliptical\", which narrowed the distance between the recast layers and made the surface structure more compact. At the same time, the ultrasonic vibration made the melted material splash and increased the surface roughness of the sample, which made the aluminum plate had superhydrophobic with a maximum contact angle of 154.92º.</div></div>","PeriodicalId":49719,"journal":{"name":"Optics and Lasers in Engineering","volume":"195 ","pages":"Article 109284"},"PeriodicalIF":3.7,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144885669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
David M.G. de la Sacristana , Luigi Ranno , Hung-I Lin , Fan Yang , Mario Cortijo , Javier Martí , Tian Gu , Carlos García-Meca , Juejun Hu
{"title":"Modeling a metalens-based system for GHz fiber mode-locked lasers","authors":"David M.G. de la Sacristana , Luigi Ranno , Hung-I Lin , Fan Yang , Mario Cortijo , Javier Martí , Tian Gu , Carlos García-Meca , Juejun Hu","doi":"10.1016/j.optlaseng.2025.109279","DOIUrl":"10.1016/j.optlaseng.2025.109279","url":null,"abstract":"<div><div>Fiber-based passive mode-locked lasers (MLLs) are a well-established technology for high-speed optical communications, capable of generating ultrashort pulses with high energy. While most commercial MLLs operate at repetition rates around 100 MHz, increasing this frequency to the GHz range introduces significant challenges, including polarization control, efficient saturation of the saturable absorber, heat dissipation and the achievement of a high free spectral range (FSR). To address these limitations, we propose a system consisting of a metalens and a 3D-printed fiber-tip collimator. The metalens is designed to selectively focus one polarization while diverging the orthogonal component, thereby addressing the polarization control. To enhance its performance and increase tolerance to positional offsets and angular tilts, we fabricated a fiber-tip collimator using two-photon polymerization (TPP). Our model suggests that this integrated system could enable the miniaturization of fiber-based MLLs while controlling polarization, enhancing the efficiency of the saturable absorber through better heat dissipation, and increasing the FSR with a shorter fiber length.</div></div>","PeriodicalId":49719,"journal":{"name":"Optics and Lasers in Engineering","volume":"195 ","pages":"Article 109279"},"PeriodicalIF":3.7,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144885668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Churan Han , Liangcai Cao , Dun Liu , Hao Tu , Qiaofeng Tan
{"title":"High uniformity flattop beam shape correction with complex amplitude aberration of the incidence","authors":"Churan Han , Liangcai Cao , Dun Liu , Hao Tu , Qiaofeng Tan","doi":"10.1016/j.optlaseng.2025.109275","DOIUrl":"10.1016/j.optlaseng.2025.109275","url":null,"abstract":"<div><div>A high uniformity flattop beam is essential in various scientific and industrial applications. However, commercial lasers often suffer from beam quality degradation, leading to a distorted beam shape. In this paper, we propose a staged Adam-stochastic parallel gradient descent (ASPGD) algorithm and a modulated performance metric for flattop beam correction. The staged optimization process contains a pre-optimization of the focus point to generate a proper initial phase mask for accelerating the flattop beam correction. The developed comprehensive performance metric is compared with the conventional mean square error and proven to be more effective. The proposed beam shaping strategy can achieve a high-uniformity flattop beam without measuring the complex amplitude aberration of the incidence. Numerical simulations validate the feasibility of the proposed method under different distorted incidences. In the experiment, we corrected the uniformity of several flattop beams under an elliptically Gaussian distributed incidence, and all beams achieved uniformity better than 0.12, as evaluated according to the ISO 13694 standard</div></div>","PeriodicalId":49719,"journal":{"name":"Optics and Lasers in Engineering","volume":"195 ","pages":"Article 109275"},"PeriodicalIF":3.7,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144885555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shuo Chen , Yu Pan , Hongyang Li , Yandong Zhang , Bo Li , Hanshuang Li , Guochao Gu , Jize Fan , Xu Zhang
{"title":"Joint glass–housing material optimization for athermal optical design via multi-objective strategy","authors":"Shuo Chen , Yu Pan , Hongyang Li , Yandong Zhang , Bo Li , Hanshuang Li , Guochao Gu , Jize Fan , Xu Zhang","doi":"10.1016/j.optlaseng.2025.109276","DOIUrl":"10.1016/j.optlaseng.2025.109276","url":null,"abstract":"<div><div>Conventional athermal optical design methods typically follow a sequential process of selecting optical glass materials first, followed by the housing material. However, if the selected housing material turns out to be unsuitable, the entire design process must be restarted, resulting in high iteration cost and reduced efficiency. To overcome this limitation, we propose a novel athermal optical design method based on a multi-objective collaborative framework for the joint selection of lens and housing material combinations. This approach enables one-step selection of glass combinations tailored to different housing materials. A novel Athermal Glass Map is constructed to unify the system’s thermal defocus, chromatic aberration, and spherical aberration responses into a single coordinate space. This unified mapping facilitates intuitive visualization and efficient evaluation of candidate material combinations. The proposed framework simultaneously optimizes key aberration metrics while considering the thermomechanical compatibility between lens and housing materials, thereby achieving effective and practical material matching for diverse structural requirements. We validate the proposed method using a transmissive optical system operating over a wide temperature range from −30 °C to 120 °C. Simulation results demonstrate that the method maintains excellent imaging performance across the entire temperature range and supports flexible matching of lens–housing combinations. Compared with traditional athermal design workflows, our approach significantly reduces repetitive optimization and dependency on designer experience, offering improved design efficiency, robustness, and applicability for complex thermal environments.</div></div>","PeriodicalId":49719,"journal":{"name":"Optics and Lasers in Engineering","volume":"195 ","pages":"Article 109276"},"PeriodicalIF":3.7,"publicationDate":"2025-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144880246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"TCIGFusion: A two-stage correlated feature interactive guided network for infrared and visible image fusion","authors":"Jiawei Liu, Guiling Sun, Bowen Zheng, Liang Dong","doi":"10.1016/j.optlaseng.2025.109265","DOIUrl":"10.1016/j.optlaseng.2025.109265","url":null,"abstract":"<div><div>Infrared and visible image fusion is aimed at generating images with prominent targets and texture details, providing support for downstream applications such as object detection. However, most existing deep learning-based fusion methods involve single-stage training and manually designed fusion rules, which cannot effectively extract and fuse features. Therefore, in this paper, we propose a two-stage correlated feature interactive guided network termed TCIGFusion. In the first stage, a Unet-like dual-branch Transformer module and dynamic large kernel convolution block (DLKB) are used to extract global features from the two source images, while the convolution blocks extract local features from the source images. In the second phase, we designed a cross attention guide module (CAGM) to interactively fuse the heterogeneously related features of the two modalities, avoiding the complexity associated with manually designing fusion rules. Furthermore, to optimize the efficacy of the fusion network, we employ a combination of image reconstruction, decomposition, and gradient loss functions for unsupervised training of the model. The superiority of our TCIGFusion is evidenced by extensive experimentation conducted on multiple public datasets. These experiments demonstrate that our method outperforms other state-of-the-art deep learning approaches, as evaluated through both subjective and objective metrics.</div></div>","PeriodicalId":49719,"journal":{"name":"Optics and Lasers in Engineering","volume":"195 ","pages":"Article 109265"},"PeriodicalIF":3.7,"publicationDate":"2025-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144880247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}