Optics and Laser Technology最新文献

{"title":"High-energy, high-repetition-rate LD side-pumped burst-mode green laser","authors":"Teng Kan ,&nbsp;Peilin Li ,&nbsp;Qiang Liu","doi":"10.1016/j.optlastec.2025.112841","DOIUrl":"10.1016/j.optlastec.2025.112841","url":null,"abstract":"<div><div>We present a LD-side-pumped Nd:YAG-based burst-mode green laser system that utilizes an electro-optical (EO) Q-switched oscillator followed by a folded power amplifier design and a second harmonic generator to achieve a compact-footprint (0.36 m²) architecture. The maximum pulse energy of 248 mJ at 1064 nm and 102 mJ at 532 nm was obtained at a pulse repetition rate of 10 kHz and burst duration of 5 ms, corresponding to a second-harmonic conversion efficiency of up to 41%. At a higher repetition rate of 50 kHz, an output of over 40 mJ per pulse at 532 nm, with a pulse width of 11.52 ns and a total burst energy of 10 J, was achieved. To the best of our knowledge, this represents the highest reported LD-pumped burst-mode green laser in terms of pulse energy and pulse repetition rate.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"188 ","pages":"Article 112841"},"PeriodicalIF":4.6,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sharpness-statistic based autofocus algorithm for Fourier ptychographic microscopy","authors":"Shu-Yuan Zhang ,&nbsp;Ying-Hui Ni ,&nbsp;Wei-Jie Deng ,&nbsp;Ming-Jie Sun","doi":"10.1016/j.optlastec.2025.112855","DOIUrl":"10.1016/j.optlastec.2025.112855","url":null,"abstract":"<div><div>Fourier ptychographic microscopy is a computational imaging technique that achieves high-resolution imaging by combining phase retrieval algorithms with synthetic aperture methods. However, defocus errors due to the misalignment of the sample can significantly degrade the reconstruction quality, leading to increased background noise and blurred details. In this manuscript, we propose a novel sharpness-statistic based autofocus algorithm to address defocus errors in Fourier ptychographic microscopy. Unlike conventional methods that infer defocus errors indirectly, our method directly applies a sharpness detection strategy to the reconstruction results, enabling more accurate correction of defocus-induced blurring. We validate the effectiveness and robustness of the sharpness-statistic based autofocus algorithm through both simulations and optical experiments, demonstrating its superiority over existing methods such as the embedded optical pupil function recovery aberration correction algorithm and lateral shift correction method. Multiple sets of quantitative experiments show that the defocus distances estimated by the proposed method under different defocusing scenarios are at least 40% more accurate than the ones estimated by the commonly used method. Consequently, the contrast of the reconstructed images is more than twice that of the commonly used method. The image quality of biological specimen is also improved with sharper details. The results indicate that the sharpness-statistic autofocus algorithm can effectively correct defocus error and enhance the image quality.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"188 ","pages":"Article 112855"},"PeriodicalIF":4.6,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759984","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":"Interconnected concentric ring resonator-based plasmonic sensor for ethanol blending detection in fuels","authors":"Rahul Pandey ,&nbsp;Kamal Kishor Choure ,&nbsp;Nitesh Mudgal ,&nbsp;Ankur Saharia ,&nbsp;Manish Tiwari ,&nbsp;Rajendra Mitharwal ,&nbsp;Ghanshyam Singh ,&nbsp;Santosh Kumar","doi":"10.1016/j.optlastec.2025.112907","DOIUrl":"10.1016/j.optlastec.2025.112907","url":null,"abstract":"<div><div>A concentric circular ring resonator with a dual stub-based plasmonic sensor configured in Metal Insulator Metal arrangement is investigated in this article. While many recent studies have achieved high sensitivity at the expense of reduced figure of merit (FOM), the proposed sensor is optimized to attain high sensitivity as well as an excellent FOM also. The numerical analysis initially reveals a maximum sensitivity of 1725 nm /RIU and an FOM of 25.7. However, by optimization of geometric parameters, such as mutual gap between the concentric ring (MG), gap between the waveguide and resonator (WG), and stub thickness, the sensor achieves a sensitivity of 1336 nm/RIU with a FOM of 61 in near- infrared region at shorter wavelengths. This optimization offers valuable insights into how these parameters influence its sensing characteristics. The excellent sensing parameters enable the sensor to detect even minimal changes in refractive index, making it suitable for biosensing applications. The sensor demonstrates its ability to identify various types of fuels through refractive index sensing. The sensor further highlights its potential by precisely detecting the concentration of ethanol in ethanol-blended petrol (EBP) and ethanol–diesel (E-diesel), both of which are emerging as promising sustainable alternatives to traditional fossil fuels.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"188 ","pages":"Article 112907"},"PeriodicalIF":4.6,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759988","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":"Super-resolution via hierarchical attention and detail enhancement transformer network","authors":"Hongdou Yao ,&nbsp;Pengfei Han ,&nbsp;Xiaofeng Wang ,&nbsp;Ju Huang ,&nbsp;Jian Yang","doi":"10.1016/j.optlastec.2025.112836","DOIUrl":"10.1016/j.optlastec.2025.112836","url":null,"abstract":"<div><div>Optical imaging is a prospective technique in probing system owing to its ability for capturing scenario information. Recently, deep super-resolution techniques have significant advantages to enhance image resolution. Nonetheless, current algorithms treat all image pixels equally and fail to adequately consider the significance of edges and textures within the images. Consequently, the resulting super-resolution images often exhibit blurriness and lack clarity in the edge and texture regions. Furthermore, the existing super-resolution framework only utilizes a limited spatial range of input information for attribution analysis, disregarding the inter-pixel importance. To enhance the reconstruction quality by activating the pixels at the edges, we propose an innovative SISR transformer network. Our contributions can be summarized as follows: (1) A hierarchical attention module is introduced that functions as a plug-and-play component, enabling improved extraction of both global semantic information and local detailed information. (2) A detail enhancement module is implemented that facilitates high-fidelity image super-resolution. Numerous experiments have been conducted, demonstrating the competitive results achieved by our approach across five publicly available datasets. The reconstructed images showcase sharper edges and more intricate textures, accentuating the efficacy of our method. Our code has been released at <span><span>https://github.com/DL-YHD/HADEM-SR/tree/main</span><svg><path></path></svg></span>.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"188 ","pages":"Article 112836"},"PeriodicalIF":4.6,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759990","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":"Multiplexing technique using photodetector arrays for quasi-distributed intensity variation optical fiber sensors system","authors":"Rafael Menegardo ,&nbsp;Arnaldo Leal-Junior","doi":"10.1016/j.optlastec.2025.112883","DOIUrl":"10.1016/j.optlastec.2025.112883","url":null,"abstract":"<div><div>This paper presents the development and characterization of a multiplexing technique for quasi-distributed optical fiber sensors based on the intensity variation detection. The technique is based on an array of photodetectors coupled to the optical fiber, where each lateral section of the optical fiber is analyzed as a sensor along the optical fiber cable. In this case, the polymer optical fiber (POF) is used due to its higher diameter and higher flexibility, which leads not only to easier coupling between the photodetector and the fiber, but also higher sensitivity for mechanical parameters detection. The proposed technique is tested under two configurations. In the first one, two sensors are developed in a single POF cable for curvature detection along the optical fiber, where the results indicated the feasibility of using such sensors to detect the curvature position at 4 different regions along the POF with a root mean squared error (RMSE) as small as 0.49 cm. Then, a 4 sensor array is developed for simultaneous force and position detection along the optical fiber, where the results indicated relative errors below 5 % on the force amplitude and position detection. Therefore, the quasi-distributed intensity variation sensors can be readily used in shape reconstruction applications, which can be integrated not only in different flexible structure, but also in textiles for wearable sensors for health monitoring and biomechanics assessment.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"188 ","pages":"Article 112883"},"PeriodicalIF":4.6,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759986","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 hybrid metallic waveguide with meta-holes for long-distance terahertz field enhancement","authors":"Wei Chen ,&nbsp;Yuanzhi Liu ,&nbsp;Jiejun Peng ,&nbsp;Min Zhang ,&nbsp;Hong Su ,&nbsp;Zhengfang Qian ,&nbsp;Shuting Fan ,&nbsp;Huawei Liang","doi":"10.1016/j.optlastec.2025.112917","DOIUrl":"10.1016/j.optlastec.2025.112917","url":null,"abstract":"<div><div>High-intensity terahertz (THz) field is crucial for various practical applications. Several structures have been used to achieve THz field enhancement, but the propagation distances of the high-intensity field can only be maintained at the wavelength or sub-wavelength scale. Here, a hybrid metallic waveguide with <em>meta</em>-holes (HMWMH) based on the combination of waveguide technologies and wavefront control methods is proposed to achieve THz field enhancement over a much longer propagation distance. By the phase modulation of <em>meta</em>-holes, THz waves incident on the waveguide can be converted into a guided mode and further focused at the center. To achieve the second field enhancement, the enhanced THz field at the focus is coupled into a triangular single ridge waveguide, which supports surface plasmon polaritons (SPPs) with deep-subwavelength mode widths and ultra-low loss. When the radius of the ridge tip and the gap between the tip and metallic plate are 15 and 100 μm, respectively, a hot spot area of 19.2 × 3.3 μm² (1.38 × 10^-5 <em>λ</em>²) and a field enhancement of 689 times are achieved simultaneously in the simulation. Theoretically the high-intensity THz field can propagate over a distance of 1.8 m due to the ultra-low loss of the SPPs, which is several orders of magnitude larger than the wavelength. According to the design, an HMWMH prototype is fabricated, and the simulated and measured results are consistent with each other. By realizing long-distance THz field enhancement, the HMWMH can greatly enhance light-matter interactions, which can promote the development of integrated THz photonic devices, THz biophotonics, and THz nonlinear photonics.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"188 ","pages":"Article 112917"},"PeriodicalIF":4.6,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759989","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":"Nanoimprint replication of laser-induced ripples for encoder applications","authors":"Gvidas Klyvis ,&nbsp;Viktoras Grigaliūnas ,&nbsp;Dalius Jucius ,&nbsp;Algirdas Lazauskas ,&nbsp;Asta Guobienė ,&nbsp;Tomas Tamulevičius ,&nbsp;Linas Puodžiukynas ,&nbsp;Albinas Kasparaitis","doi":"10.1016/j.optlastec.2025.112912","DOIUrl":"10.1016/j.optlastec.2025.112912","url":null,"abstract":"<div><div>Laser-induced periodic surface structures (LIPSS) offer unique optical properties as dark marking which is applicable for optical encoders, but their direct laser fabrication is costly and slow. This study introduces a cost-effective and scalable alternative: thermal nanoimprint replication of LIPSS onto flexible, metallized polyethylene terephthalate (PET) film. LIPSS were initially fabricated on stainless steel using picosecond laser ablation and then replicated onto aluminum-coated PET film via thermal nanoimprinting at varying temperatures. Atomic force microscopy confirmed successful replication, with optimal fidelity achieved at 180 °C, preserving the <em>ca.</em> 450 nm periodicity of the LIPSS while transferring ripple heights from 114 nm in steel master to 80 nm in PET replica. Reflectance measurements using UV–Vis-NIR spectroscopy and focused laser beam reflection demonstrated significant contrast between rippled and not rippled areas on the PET film, comparable to the steel master and sufficient for optical encoder applications. Frequency domain analysis of focused laser reflectance scans confirmed consistent periodicity in both master and replica. These results demonstrate that thermal nanoimprint is a viable, scalable, and cost-effective technique for replicating LIPSS onto flexible substrates, enabling the production of high-contrast optical encoder scales for various sensing and positioning applications.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"188 ","pages":"Article 112912"},"PeriodicalIF":4.6,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747205","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":"Study on oscillating laser welding of 6061-T6 aluminum alloy medium-thick plate: Energy distribution, joint forming, texture evolution, and mechanical properties","authors":"Jiasi Cai ,&nbsp;Zipeng Ouyang ,&nbsp;Hongxi Jin ,&nbsp;Yingjie Kong ,&nbsp;Yanhong Wei","doi":"10.1016/j.optlastec.2025.112910","DOIUrl":"10.1016/j.optlastec.2025.112910","url":null,"abstract":"&lt;div&gt;&lt;div&gt;This study systematically investigates the implementation of beam oscillation into conventional laser welding of 6061-T6 aluminum alloy, with the objective of optimizing weld seam appearance, mitigating defects, and enhancing the mechanical properties of welded joints. Computational analyses reveal that frequency (&lt;em&gt;f&lt;/em&gt;) and welding speed (&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;v&lt;/mi&gt;&lt;mi&gt;l&lt;/mi&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;) exert a significant influence on the trajectory overlap rate (&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;O&lt;/mi&gt;&lt;mi&gt;r&lt;/mi&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;), while amplitude (&lt;em&gt;A&lt;/em&gt;) exhibits negligible impact. The transient velocity (&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;v&lt;/mi&gt;&lt;mrow&gt;&lt;mi&gt;transient&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;) of the laser beam fluctuates within a defined range, modulating the transient linear energy density (&lt;em&gt;P&lt;/em&gt;/&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;v&lt;/mi&gt;&lt;mrow&gt;&lt;mi&gt;transient&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;). The essential effect of beam oscillation lies in its capacity to redistribute laser energy deposition on the processing surface. To quantitatively characterize this phenomenon, an energy distribution model (EDM) was developed, incorporating laser energy attenuation and beam superposition effects. A comprehensive experimental investigation was conducted to evaluate the influence of &lt;em&gt;f&lt;/em&gt;, &lt;em&gt;A&lt;/em&gt;, and &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;v&lt;/mi&gt;&lt;mi&gt;l&lt;/mi&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; on weld formation characteristics, cross-sectional geometry, texture evolution, and mechanical properties. Optical microscopy (OM) and X-ray detection analyses demonstrate that beam oscillation effectively suppresses defect formation, including collapse, undercutting, spatter, and internal porosity. Increasing &lt;em&gt;f&lt;/em&gt;, &lt;em&gt;A&lt;/em&gt;, or &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;v&lt;/mi&gt;&lt;mi&gt;l&lt;/mi&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; results in a reduction of fusion zone width and penetration depth due to decreased heat input, with penetration depth exhibiting greater sensitivity to these parameters compared to weld width. A distinctive “double molten pools” phenomenon is observed, arising from an energy distribution profile characterized by a “low center, high sides” configuration, where a significant energy difference between the center and sides facilitates this behavior. When &lt;em&gt;ΔE&lt;/em&gt; is below 4.25 × 10&lt;sup&gt;11&lt;/sup&gt; J/m&lt;sup&gt;2&lt;/sup&gt;, heat accumulation in the central region inhibits the formation of “double molten pools.” Conversely, &lt;em&gt;ΔE&lt;/em&gt; exceeding 4.51 × 10&lt;sup&gt;11&lt;/sup&gt; J/m&lt;sup&gt;2&lt;/sup&gt; induces localized heat buildup on both sides, promoting the formation of the “double molten pools.” Microstructural characterization using OM and electron backscatter diffraction (EBSD) reveals that repeated thermal cycles induced by the oscillating beam promote grain coarsening in the heat-affected zone (HAZ). The multi-columnar dendritic structures on both sides of the weld exhibit varying lengths and primary dendrite arm spacing (PDAS) due to uneven heat input. The ","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"188 ","pages":"Article 112910"},"PeriodicalIF":4.6,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747202","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":"Assembling magneto-optical heterostructures for all-optical multi-functional devices","authors":"Jie Xu ,&nbsp;Yun You ,&nbsp;Sanshui Xiao ,&nbsp;Lujun Hong ,&nbsp;Yun Shen ,&nbsp;Kosmas L. Tsakmakidis ,&nbsp;Yamei Luo","doi":"10.1016/j.optlastec.2025.112858","DOIUrl":"10.1016/j.optlastec.2025.112858","url":null,"abstract":"<div><div>All-optical computing has recently emerged as a vibrant research field in response to the energy crisis and the growing demand for information processing. However, the efficiency of subwavelength-scale all-optical devices remains relatively low due to challenges such as back-scattering reflections and strict surface roughness. Furthermore, achieving multifunctionality through the reassembly of all-optical structures has thus far been rarely accomplished. One promising approach to address these issues is the utilization of one-way edge modes. This work proposes four types of deep-subwavelength (<span><math><mrow><mo>∼</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>2</mn></mrow></msup><msub><mrow><mi>λ</mi></mrow><mrow><mn>0</mn></mrow></msub></mrow></math></span>, where <span><math><msub><mrow><mi>λ</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span> is the wavelength in vacuum) all-optical functional devices based on yttrium iron garnet (YIG): a phase modulator, a filter, a splitter, and logic gates. These devices are based on robust one-way edge modes and/or index-near-zero (INZ) modes but do not require an external magnetic field, which can allow for flexible assembly. In particular, a phase modulation range spanning from <span><math><mrow><mo>−</mo><mi>π</mi></mrow></math></span> to <span><math><mi>π</mi></math></span>, a perfect filter that divides the input port’s one-way region into two output one-way regions with equal bandwidth, a multi-frequency splitter with an equal splitting ratio (e.g., 50/50), and self-consistent logic gates relying on INZ modes are investigated. Our findings may find applications in compact optical calculations and integrated optical circuits.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"188 ","pages":"Article 112858"},"PeriodicalIF":4.6,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747206","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":"Online monitoring of surface forming quality in laser-arc hybrid butt welding with uneven joint gaps based on arc signal diagnosis","authors":"Kaiqin Xu,&nbsp;Leshi Shu,&nbsp;Ping Jiang,&nbsp;Yuan Wang,&nbsp;Nian Zhou","doi":"10.1016/j.optlastec.2025.112850","DOIUrl":"10.1016/j.optlastec.2025.112850","url":null,"abstract":"<div><div>High-power laser-arc hybrid welding is commonly employed in the welding of medium-thickness steel. In full-penetration butt welding, butt joint gaps are particularly prevalent, especially as plate thickness increases, which in turn tend to exacerbate underfill and surface collapse defects. Consequently, it is essential to monitor the surface collapse defects during the welding process for medium-thickness steel. In this paper, a novel method is proposed to monitor surface collapse defects for laser-arc hybrid welding of medium-thickness steel with uneven joint gaps based on voltage signal diagnosis and machine learning. Firstly, the interrelation mechanism between the butt joint gap, surface collapse, and the voltage signal is analyzed with high-speed images, which is adopted to guide the time/frequency feature extraction in the proposed method. Then, it is found that the changes in peak and base voltages, along with the instantaneous frequency of arc pulse captured through variational mode decomposition (VMD), reflect the surface collapse defect, significantly affected by the butt gap. On this basis, a back propagation neural network (BPNN) is constructed to identify the extracted features, realizing the monitoring of the surface collapse defects with a precision of 94.24%.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"188 ","pages":"Article 112850"},"PeriodicalIF":4.6,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747095","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}