Optics and Laser Technology最新文献

{"title":"Rapid 4D printing of hydrogel microactuators by single-exposure of femtosecond structured beams","authors":"Yue Yang ,&nbsp;Erse Jia ,&nbsp;Chen Xie ,&nbsp;Minglie Hu","doi":"10.1016/j.optlastec.2025.113305","DOIUrl":"10.1016/j.optlastec.2025.113305","url":null,"abstract":"<div><div>Femtosecond laser direct writing (FLDW) method enables the flexible three-dimensional (3D) molding of intelligent microactuators with submicron resolution, which are capable of adaptive deformation when exposed to external stimuli. However, their mass production is still limited by complicated, multi-material composites or time-consuming programmed point-by-point scanning strategies to date. Here, a novel four-dimensional (4D) printing method based on two-photon polymerization is proposed to achieve the rapid molding of hydrogel microactuators. Wavefront and amplitude co-modulation based on a spatial light modulator is introduced into the architecture of 4D printing, thus endowing the hydrogel material with adaptive shape morphing function with a single exposure. The processing efficiency is improved by  2 orders of magnitude, providing higher throughput and large-area manufacturing capability. This approach allows for the efficient prototyping of microgrippers with controllable bending properties for in-situ capture of polystyrene microspheres. Moreover, the microtube arrays can serve as 3D cell culture scaffolds, enabling the rapid construction of large-scale cell growth environment. Altogether, this flexible, customizable, and high-throughput 4D printing strategy paves the way for the construction of intelligent microactuators with promising applications in particle manipulation, biomedicine, tissue engineering, and other fields.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"191 ","pages":"Article 113305"},"PeriodicalIF":4.6,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Polarization-Insensitive broadband achromatic inverse design method for high numerical aperture metasurfaces","authors":"Tianyu Zhao ,&nbsp;Yue Wang ,&nbsp;Fengfeng Shu ,&nbsp;Xiao lv ,&nbsp;Yihui Wu","doi":"10.1016/j.optlastec.2025.113273","DOIUrl":"10.1016/j.optlastec.2025.113273","url":null,"abstract":"<div><div>In biomedical imaging, especially in cellular and single-molecule imaging, multi-wavelength imaging and high resolution are critical performance indicators. Traditional high numerical aperture (NA) optical systems can improve resolution, but chromatic aberration correction is complex and affects the practical application of the system. This research proposes an inverse design method based on multi-wavelength metasurfaces, using super-oscillation phase modulation technology to achieve precise control of light fields across different wavelengths while maintaining consistent unit structure. Based on this approach, we designed a metasurface with a numerical aperture (NA) of 0.8, which demonstrates a 3.9 % chromatic aberration tolerance across the 560–740 nm wavelength range, with a focal depth range of 3 to 4 times the wavelength. Building upon this, the structure was further optimized using the adjoint optimization method with the initial structure as a starting point, achieving a full field of view of 20°.Additionally, the structure exhibits polarization-insensitive characteristics. This inverse design method provides a novel solution for chromatic aberration elimination and resolution enhancement in multi-wavelength optical systems, advancing metasurface technology towards practical applications.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"191 ","pages":"Article 113273"},"PeriodicalIF":4.6,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel coherent gradient sensor for quadric surface and its application in laser repair process","authors":"Qixian Zhong,&nbsp;Chuanqing Geng,&nbsp;Huimin Xie","doi":"10.1016/j.optlastec.2025.113327","DOIUrl":"10.1016/j.optlastec.2025.113327","url":null,"abstract":"<div><div>In-situ deformation measurement of laser directed energy deposition (LDED) repaired product is conducive to the process monitoring and troubleshooting of LDED, laying experimental foundations for further LDED process parameter optimization as well as quality control of the product. However, the diversity of repair structures and process parameters may form complex deformation on curved surface, demanding for wider measurement range of in-situ monitoring method. Considering the relevant requirements, this paper puts forward a novel theoretical model of coherent gradient sensor for curved surface (curve-CGS), and the accurate deformation measurement of curved surface has been achieved by CGS for the first time. Then, an integrated curve-CGS system with translation compensation system (TCS) is designed and established independently for accurate quadric measurement based on the theoretical model, and two curved surface measurement modes: the optimal compensation for minimum full-field systematic error and the confocal compensation, are proposed and analyzed through simulation. The accuracy of curve-CGS system is then experimentally studied through measurement of different spherical mirrors with standard curvature. Results demonstrate that the proposed curve-CGS achieves curvature measurement accuracy<span><math><mrow><mi>Δ</mi><mi>κ</mi><mo>/</mo><mi>κ</mi></mrow></math></span> &lt; 4 % within the extended measurement range of 0–2 <span><math><msup><mrow><mi>m</mi></mrow><mrow><mo>-</mo><mn>1</mn></mrow></msup></math></span>, while conventional CGS shares the same accuracy magnitude within 0–0.2 <span><math><msup><mrow><mi>m</mi></mrow><mrow><mo>-</mo><mn>1</mn></mrow></msup></math></span>. Finally, the curve-CGS system is applied in zig-zag LDED multi-layer repair process to in-situ monitor the full-field residual deformation (RD) of curved metal substrate. Based on curvature data, the spherical and aspherical RD accumulation of each deposition layer in LDED repair is analyzed. Results show the spherical curvature of repaired components remains basically the same while the aspherical curvature continues to increase and accumulate after each deposition layer, which is fundamental to the anisotropic distribution of RD. The curve-CGS proposed in this study expands the measurement range of CGS, which has a good potential in future applications of curved surface deformation measurement at real working sites.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"191 ","pages":"Article 113327"},"PeriodicalIF":4.6,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A multicore fiber platform for distributed temperature sensing enhanced by machine learning algorithms","authors":"A. Kokhanovskiy ,&nbsp;D. Sakhno ,&nbsp;Z.E. Munkueva ,&nbsp;E.V. Golikov ,&nbsp;A.V. Dostovalov ,&nbsp;S.A. Babin","doi":"10.1016/j.optlastec.2025.113262","DOIUrl":"10.1016/j.optlastec.2025.113262","url":null,"abstract":"<div><div>Machine learning algorithms have attracted much interest for their efficiency in processing signals measured by photonic sensors. In this study, we propose a multicore fiber platform for distributed temperature sensors enhanced by machine learning algorithms. Our experimental setup involves densely inscribed FBGs in the central core of a multicore fiber, whereas sparsely located FBGs in the peripheral cores serve as reference temperature sensors. The goal of the machine learning algorithm is to predict the positions of the individual FBG reflectance peaks from the raw reflectance spectrum of the dense FBG array. We evaluated the performance of Long Short-Term Memory (LSTM) neural network and CatBoost algorithm for measuring the temperature distribution. We have shown that both algorithms maintain high precision in predicting the temperature distribution even in cases where different reflectance peaks overlap. Our findings highlight the significant impact of temperature–time dynamics during the training process, which can greatly increase accuracy. In our study, the CatBoost algorithm outperformed the LSTM model when a variety of temporal dynamics of temperature change were used in the training dataset. The LSTM model demonstrated greater generalization in learning sensor responses, performing better on an unseen dataset with pronounced seasonality. Our results demonstrate the potential to enhance the wavelength-division multiplexing capabilities of distributed FBG sensors, even with a limited spectral bandwidth of the optical interrogator, using machine learning algorithms. This can improve spatial resolution and extend the sensing range of distributed FBG sensors.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"191 ","pages":"Article 113262"},"PeriodicalIF":4.6,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced ghost imaging reconstruction via a Chambolle-Pock inspired deep unfolding network","authors":"Chang Zhou ,&nbsp;Jie Cao ,&nbsp;Haifeng Yao ,&nbsp;Huan Cui ,&nbsp;Haoyu Zhang ,&nbsp;Qun Hao","doi":"10.1016/j.optlastec.2025.113323","DOIUrl":"10.1016/j.optlastec.2025.113323","url":null,"abstract":"<div><div>Ghost imaging is an innovative imaging modality that addresses the ill-posed reconstruction challenges associated with the acquisition of sparse measurements using a bucket detector. This technique holds extensive potential for applications and possesses significant practical utility across various domains. Deep unfolding networks (DUNs) based on compressive sensing techniques and deep learning methods have been applied to ghost imaging reconstruction in recent years due to their adaptive solid learning capabilities and inherent interpretability. However, most DUNs exhibit a lack of sensitivity to the reconstruction of image details at low sampling rates, resulting in the introduction of distortion and blurring in complex images. In this paper, we propose a ghost imaging method based on a deep unfolding network inspired by the Chambolle-Pock (CP) Algorithm. This method combines the CP algorithm with DUNs, enhancing the visual quality of reconstructed images while reducing the number of model parameters. Furthermore, we propose a multi-scale information mapping module for extracting and integrating the sensitivity of different scale feature information, thereby mitigating information loss in the reconstruction stage and improving image reconstruction details. The proposed method is shown to enhance the reconstruction quality of images, particularly in terms of detail recovery, and to outperform existing techniques.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"191 ","pages":"Article 113323"},"PeriodicalIF":4.6,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cavitation-driven nanosecond laser irradiation assisted chemical–mechanical-polishing (CMP) for atomic-scale material removal of 4H-SiC","authors":"Zirui Wang ,&nbsp;Yuguang Zhu ,&nbsp;Yang Peng ,&nbsp;Tianyu Zhang ,&nbsp;Yongguang Wang ,&nbsp;Qingsheng Liu ,&nbsp;Haidong He ,&nbsp;Chuanyang Wang","doi":"10.1016/j.optlastec.2025.113328","DOIUrl":"10.1016/j.optlastec.2025.113328","url":null,"abstract":"<div><div>Silicon carbide (SiC) is one of the most promising three-generation semiconductor materials owing to its remarkable properties and numerous potential applications. Nevertheless, the polishing efficiency of hard-to-process single crystal SiC remains a significant challenge due to its high hardness and chemical inertness. A novel approach by employing nanosecond laser irradiation in deionized water as a pre-process for the chemical mechanical polishing (CMP) process was presented. By irradiating the Si-face in transverse and cross-scanning irradiation sequentially, the SiC wafers were processed with CMP using the eco-friendly polishing slurry. The polishing performance of underwater nanosecond laser assisted (UNLA)-CMP, including material removal rate (<em>MRR</em>) and surface roughness (<em>R</em>_a), was evaluated, and the mechanisms of underwater nanosecond laser irradiation of SiC surfaces were investigated. The results indicate that the proposed UNLA-CMP process can meet the various requirements for surface accuracy in the surface polishing of SiC wafers. The study offers a beneficial exploration of applying the post-treatment of underwater nanosecond laser irradiation to the efficient atomic-scale SiC-CMP process.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"191 ","pages":"Article 113328"},"PeriodicalIF":4.6,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Broadband second harmonic generation from a cladding waveguide fabricated by ultrafast laser ablation in KTN crystal","authors":"Siwen Ai ,&nbsp;Zhixiang Chen ,&nbsp;Bin Zhang ,&nbsp;Feng Chen ,&nbsp;Yuechen Jia ,&nbsp;Hongliang Liu","doi":"10.1016/j.optlastec.2025.113349","DOIUrl":"10.1016/j.optlastec.2025.113349","url":null,"abstract":"<div><div>In this paper, we report a cladding waveguide with a broadband second harmonic generation (SHG) based on second-order nonlinearity in relaxation ferroelectrics. The cladding waveguide was fabricated in a KTa_1-xNb_xO₃ (KTN) crystal by the femtosecond laser direct writing (FLDW) technology. The end-face coupling system has been used to measure the near-field intensity distribution, the spectra of SHG have been detected by the spectrometers and the local paraelectric-ferroelectric phase transition has been verified by Raman spectra. The experimental results indicate that the cladding waveguide presents excellent performance with polarization independence 515-nm SHG output under a 1030 nm femtosecond input laser, and 200-nm bandwidth SHG output under a picosecond supercontinuum source. This work demonstrates the application potential of FLDW technology for fabricating miniaturized nonlinear photonic components of integrated devices on an optical crystalline platform.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"191 ","pages":"Article 113349"},"PeriodicalIF":4.6,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Photonic-assisted radar for simultaneous detection of velocity, distance and angle of arrival of multiple targets","authors":"Mengmeng Wu ,&nbsp;Jianxin Ma","doi":"10.1016/j.optlastec.2025.113348","DOIUrl":"10.1016/j.optlastec.2025.113348","url":null,"abstract":"<div><div>A photonic-assisted radar scheme that utilizes a V-shaped Linear Frequency Modulated (LFM) signal to track multiple targets simultaneously is proposed. The de-chirping process is performed by a dual-polarized Mach-Zehnder modulator (Dpol-MZM), with a reference signal frequency shifted by Δ<em>f</em> relative to the transmitted signal to achieve the desired signal processing. The symmetry of the beat frequencies of the up-chirp and down-chirp segments can be used to eliminate direction ambiguity and false targets in measurements. By analyzing the beat frequency components, the velocity, distance and angle of arrival (AOA) of multiple targets can be accurately determined. Proof-of-concept experiments have verified the proposed scheme’s capability for multi-target detection by simultaneously tracking three targets at six different positions. The measurement ranges for the Doppler frequency shift (DFS), distance, and AOA are −100 kHz to 100 kHz, 75 m to 750 m, and −90° to 90°, with errors of 0.88 Hz, 0.93 cm, and 1.02°, respectively.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"191 ","pages":"Article 113348"},"PeriodicalIF":4.6,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The devil’s staircase in a figure-of-nine laser","authors":"Bo Yuan ,&nbsp;Junsong Peng ,&nbsp;Huiyu Kang ,&nbsp;Yulin Sheng ,&nbsp;Xinyu Hu ,&nbsp;Xiuqi Wu ,&nbsp;Ying Zhang ,&nbsp;Heping Zeng","doi":"10.1016/j.optlastec.2025.113310","DOIUrl":"10.1016/j.optlastec.2025.113310","url":null,"abstract":"<div><div>Breathers in ultrafast lasers serve as a promising platform for investigating fascinating fractal dynamics—the devil’s staircase. This phenomenon has been exclusively investigated in lasers with ring configurations. It is natural to ask whether other cavity configurations can also present such fractal dynamics. The figure-of-nine laser cavity is widely employed in engineering by virtue of its stability. Here we show numerically that devil’s staircase can also be observed in a figure-of-nine laser, thereby validating the universality of the fractal phenomena in ultrafast laser systems. While devil’s staircase was previously obtained by tuning the pump power in a ring laser, the figure-of-nine laser provides a new control parameter to observe the fractal phenomenon—the phase bias. A discrete model based on the generalized nonlinear Schrödinger equation is employed in this work.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"191 ","pages":"Article 113310"},"PeriodicalIF":4.6,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of substrate rotational speed and phase transition on β-V2O5 for temperature-sensitive thin films","authors":"Natasia Fungfuang ,&nbsp;S.Tipawan Khlayboonme ,&nbsp;Mettaya Kitiwan","doi":"10.1016/j.optlastec.2025.113296","DOIUrl":"10.1016/j.optlastec.2025.113296","url":null,"abstract":"<div><div>The phase stability and reversibility of V₂O₅ are crucial for smart, contactless optical thermal sensors. Controlling phase characteristics optimizes device performance, particularly by achieving lower phase-transition temperatures with reversible properties. This study examines the effects of substrate rotational speed on the phase content and homogeneity of V₂O₅ thin films deposited via radiofrequency magnetron sputtering using an inclined magnetron head and an O₂-reactive process. Characterized using X-ray diffraction, electron microscopy, Hall effect measurements, and ultraviolet–visible spectroscopy, the films exhibited a mixture of β-monoclinic and β-tetragonal phases. Increasing the substrate rotational speed from 0 to 40 rpm increased the film thickness from 125 to 220 nm but reduced the crystallite size from 16.8 to 7.9 nm for the β-monoclinic phase. The direct bandgap energy decreased from 3.582 to 2.56 eV, and the electron density decreased from 2.92 × 10¹⁸ to 5.2 × 10¹⁷ cm⁻³, suggesting suppressed depletion of vanadyl oxygen in the film structure. Optical analysis revealed that the dispersive energy for the β-monoclinic phase increased from 24.7 to 30.3 eV as the rotational speed increased—attributed to stronger polarization due to lattice vibrations. The responses of the annealed and as-deposited films to thermally induced stimuli were investigated. During cooling to 100 °C, the β-tetragonal phase content continued to increase, whereas the β-monoclinic phase content decreased and appeared to revert to levels observed before heating. This result revealed a reversible β-monoclinic phase transformation during cooling, indicating the potential of amorphous β-monoclinic V₂O₅ films for chromic and temperature-sensitive sensors with repeatable performance.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"191 ","pages":"Article 113296"},"PeriodicalIF":4.6,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144212958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}