Optics and Laser Technology最新文献

{"title":"Time-resolved two-dimensional electron density profiles of laser-produced tin droplet plasma","authors":"Huiming Qi ,&nbsp;Qin Sun ,&nbsp;Tianyi Wang ,&nbsp;Duluo Zuo ,&nbsp;Xinbing Wang","doi":"10.1016/j.optlastec.2025.112623","DOIUrl":"10.1016/j.optlastec.2025.112623","url":null,"abstract":"<div><div>We report results from the optical interferometric diagnosis of laser-produced tin droplet plasma for the extreme ultraviolet (EUV) light sources. Nomarski interferometry was utilized to study the early stages of the laser-produced tin droplet plasma formation for the first time and obtain its spatial distribution of electron density. To mitigate the plasma’s heating and suppress background radiation of plasma, we employed the low-power CW probe laser and narrow-band filter in our experiment. The time-resolved interference patterns were recorded by ICCD. The electron density distribution within the plasma was ascertained by analyzing the phase differences observed in the interference patterns, employing the method of inverse Abel transform. Our experimental results indicate that the plasma electron density varies between 3 × 10¹⁸ and 8 × 10¹⁸ cm⁻³.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"186 ","pages":"Article 112623"},"PeriodicalIF":4.6,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143479921","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":"Gallium arsenide metasurfaces for multiple vortex beam deflections at visible","authors":"Meng-Hsin Chen,&nbsp;Cyun-Yu Lin","doi":"10.1016/j.optlastec.2025.112645","DOIUrl":"10.1016/j.optlastec.2025.112645","url":null,"abstract":"<div><div>The development of metasurfaces capable of producing highly deflected beams is extremely desirable for applications requiring large numerical apertures (NAs) and wide fields of view (FOVs). Such performance demands the fabrication development of <em>meta</em>-structures composed of high-refractive-index, high-aspect-ratio dielectric materials. Furthermore, optical vortex beams (VBs), a fundamental aspect of structured light, have garnered significant attention for their diverse applications. In this work, high-aspect-ratio GaAs <em>meta</em>-structures have been successfully developed to realize multifunctional metasurfaces capable of generating vortex beams and Gaussian beams with deflection angles as high as 75° relative to the optical axis under a normal incidence wavelength of 650 nm, operating in reflective mode. In addition, the broadband characteristics of these multifunctional GaAs metasurfaces have also been demonstrated, pointing out their potential to enable sophisticated structured light generation at high deflection angles. These findings pave the way for future advancements in optical systems requiring compact, versatile, and high-performance metasurfaces.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"186 ","pages":"Article 112645"},"PeriodicalIF":4.6,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143479917","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":"Laser transmission welding of transparent polymers based on femtosecond laser surface pretreatment","authors":"Dongyang Wang ,&nbsp;Kaige Liu ,&nbsp;Jianpang Zhai ,&nbsp;Shuangchen Ruan ,&nbsp;Yan Kang ,&nbsp;Qingyang Wu","doi":"10.1016/j.optlastec.2025.112669","DOIUrl":"10.1016/j.optlastec.2025.112669","url":null,"abstract":"<div><div>Laser transmission welding (LTW) technology has garnered widespread attention in polymer welding due to its unique advantages. Among the challenges in LTW research of polymers, achieving welds between two transparent polymers without using absorbers is one of the most difficult issues. To date, there have been no reports of effective welding of transparent polymers using near-infrared (NIR) lasers without the use of absorbers, because transparent polymers have low absorption rates for commonly used NIR lasers, resulting in insufficient absorption of laser energy to achieve effective welding. This study presents a femtosecond laser surface pretreatment approach that modifies polymer surface roughness to enhance absorption rates. The effects of various ablation parameters on the roughness and laser absorption of polycarbonate (PC) samples were investigated. Effective welding of PC/PVC was achieved using both NIR (808 nm) and mid-infrared (1940 nm) lasers, and the shear strength of the welded joints was tested. The applicability of this approach was further validated across multiple transparent polymer sets. By enabling NIR laser transmission welding without absorbers, this method offers significant potential for applications in the biomedical, food, and medical industries.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"186 ","pages":"Article 112669"},"PeriodicalIF":4.6,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143479916","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":"Improving microstructure uniformity and mechanical properties of Al-Si coating 22MnB5 steel welded joints by pulsed Laser-TIG hybrid welding","authors":"Ronghao Han ,&nbsp;Jiyan Liu ,&nbsp;Daxin Ren ,&nbsp;Gang Song ,&nbsp;Liming Liu","doi":"10.1016/j.optlastec.2025.112673","DOIUrl":"10.1016/j.optlastec.2025.112673","url":null,"abstract":"<div><div>The 22MnB5 steel with Al-Si coated exhibits high strength, robust corrosion resistance, and outstanding high-temperature formability, making it a crucial material for automotive lightweight and safety enhancement. However, traditional continuous laser welding (CLW) encounters limitations due to the molten pool’s rapid solidification, which hampers the complete and uniform diffusion of Al elements from the coating into the molten pool. Consequently, Al element segregation occurs in the fusion zone, forming α-ferrite − a critical factor in welded joint failure. To address this issue, the study introduced a novel technology, pulsed laser-TIG hybrid welding (PLTW), designed to overcome these challenges. The novel technology integrates an arc heat source to decelerate the solidification rate of the molten pool. Furthermore, the pulse laser stirs the molten pool, facilitating the complete diffusion of Al elements within it. Consequently, without removing the coating, the formation of α-ferrite was minimized, thereby enhancing the strength and ductility of the welded joint. After hot stamping, compared to CLW, the PLTW welded joint exhibited a more homogeneous microstructure and suppressed fusion zone softening, significantly increasing tensile strength by 13.3% and elongation by 39.1%. Nevertheless, due to the higher heat input from the arc heat source, thinning occurred on both sides of the fusion zone of the PLTW joint. Future research will investigate the use of PLTW with filler wire to address the thinning issue on both sides of the weld, aiming further to enhance the strength and ductility of the welded joint.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"186 ","pages":"Article 112673"},"PeriodicalIF":4.6,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143479918","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":"Laser-irradiated synthesis of gold nanoworms with tunable near-infrared absorption for enhanced catalytic activity","authors":"Ayesha Noor ,&nbsp;Waqqar Ahmed ,&nbsp;Ameenah N. Al-Ahmadi ,&nbsp;Abdel-Haleem Abdel-Aty ,&nbsp;Hamza Qayyum","doi":"10.1016/j.optlastec.2025.112667","DOIUrl":"10.1016/j.optlastec.2025.112667","url":null,"abstract":"<div><div>The synthesis of anisotropic nanoparticles with the ability to absorb light in the near-infrared region is of great interest due to their applications in nanotherapy and nanodiagnostics. Here, we describe the fabrication process of gold nanoworms (Au NWs) through laser irradiation of gold nanospheres (Au NSs) dispersed in a liquid medium. The resulting Au NWs exhibit a broadband plasmon absorption across the visible to near-infrared spectrum. The entire formation process is conducted in the presence of ethanol without the use of any templating agent, thereby yielding surfactant-free Au NWs. This feature enhances their surface reactivity and ensures biocompatibility. The formation process of Au NWs is intricately dependent on laser parameters; the extent of Au NWs formation escalated with increasing laser energy and irradiation time. The optimal conditions for the Au NWs formation are 120 mJ laser energy and 4 min of laser exposure time. Furthermore, varying the concentration of ethanol in the growth medium enables control over the length of nano-worms. To investigate their catalytic activity, the Au NWs with varying aspect ratios are used to reduce azo dyes such as methyl orange (MO) and rhodamine-b (RhB). Au NWs are found to have far superior catalytic activity than their spherical counterparts. Moreover, high aspect ratio Au NWs are more efficient catalysts than those with low aspect ratios. The long Au NWs demonstrated 5.5-fold and 2.2-fold higher catalytic activity than the Au NSs for MO and RhB, respectively.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"186 ","pages":"Article 112667"},"PeriodicalIF":4.6,"publicationDate":"2025-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143471547","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":"Reconstruction in off-axis digital holography based on hybrid clustering and the fractional Fourier transform","authors":"Ying Guan,&nbsp;Ze Cui,&nbsp;Wenjing Zhou","doi":"10.1016/j.optlastec.2025.112622","DOIUrl":"10.1016/j.optlastec.2025.112622","url":null,"abstract":"<div><div>The fractional Fourier transform (FRFT) introduces fractional-order parameters and provides greater flexibility and adaptability than the conventional Fourier transform, thus offering new possibilities for reconstruction in digital holography. This paper proposes a reconstruction method in off-axis digital holography based on hybrid clustering and FRFT. First, a hybrid clustering algorithm combining K-means and a Gaussian mixture model was used to accurately classify the spectrum information of holograms, effectively suppressing zero-order spectrum interference. Then the rotation additivity property of the FRFT, combined with a particle swarm optimization algorithm, was used to precisely estimate the optimal fractional-order parameters of the hologram. Finally, high-quality amplitude and phase reconstructions were achieved using the FRFT reconstruction of hologram. Simulation and experimental results demonstrated that the proposed method significantly improved the reconstruction quality of holograms. The findings of this study provide an effective solution for enhancing off-axis digital holography imaging quality, with important implications for the development of precision microstructure detection and high-resolution biological imaging technology.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"186 ","pages":"Article 112622"},"PeriodicalIF":4.6,"publicationDate":"2025-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474392","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":"Design, fabrication, and testing of freeform mirror-based head-up display system","authors":"Sumit Kumar,&nbsp;Wenbin Zhong,&nbsp;James Williamson,&nbsp;Prashant Kumar,&nbsp;Thomas Furness,&nbsp;Shan Lou,&nbsp;Wenhan Zeng,&nbsp;Xiangqian Jiang","doi":"10.1016/j.optlastec.2025.112653","DOIUrl":"10.1016/j.optlastec.2025.112653","url":null,"abstract":"<div><div>Head-up displays (HUDs) in aircraft, spacecraft, and automobiles are principally considered a safety assistance system. HUDs are transparent displays that are installed in the vehicle in an order that the observer, driver, or pilot can see pertinent information in their line of sight. Current HUD systems are developed with conventional optics, which requires a large amount of space occupancy in the cabin or cockpit, thus creating accommodation challenges for the other devices. HUD systems containing multiple components have more operational challenges such as precise micron-level angular movement of folding mirror and associated significant amount of power drain of the vehicle’s battery. In this research article, a HUD design containing a single freeform mirror without compromising the optical performance of the system is proposed. The novel design provides the opportunity to make the system more compact and energy efficient as no separate electro-mechanical component is required for beam folding and additional tracking devices. Also, the larger Eyebox dimension obtained with the use of freeform mirror makes the HUD system definitive for extreme operational conditions and flexible observation from various heights. With the utilization of concurrent engineering, a two-phase authentic developmental process chain is presented for the freeform mirror-based HUD system. Ultra-precision single-point diamond turning with on-machine surface measurement is utilized to convert the design of various surfaces to physical functional elements of sub-micron level form accuracy and nano-metric level surface roughness. Finally, the HUD system is validated through optical functional testing.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"186 ","pages":"Article 112653"},"PeriodicalIF":4.6,"publicationDate":"2025-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143471545","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":"Narrow-linewidth, high-power, widely-tunable III-V/Si3N4 hybrid integrated external cavity laser","authors":"Changjin Yang ,&nbsp;Yao Li ,&nbsp;Qiang Cui ,&nbsp;Lei Liang ,&nbsp;Li Qin ,&nbsp;Langyong Huang ,&nbsp;Yongyi Chen ,&nbsp;Yubing Wang ,&nbsp;Yue Song ,&nbsp;Cheng Qiu ,&nbsp;Chuantao Zheng ,&nbsp;Dabing Li ,&nbsp;Lijun Wang","doi":"10.1016/j.optlastec.2025.112627","DOIUrl":"10.1016/j.optlastec.2025.112627","url":null,"abstract":"<div><div>We present a narrow-linewidth, high-power, widely-tunable III-V/Si₃N₄ hybrid integrated external cavity laser. The laser is composed of a reflector semiconductor optical amplifier chip, a Si₃N₄ external cavity with triple micro-ring resonators, and a semiconductor optical amplifier chip. The laser achieved a side-mode suppression ratio (SMSR) greater than 50 dB across an 89 nm wavelength tuning range. The maximum fiber output power reached 101.4 mW at the wavelength of 1550 nm. The minimized Lorentzian linewidth was 0.252 kHz, with a minimum RIN of −156 dBc/Hz. This exceptional performance positions the laser as a strong candidate for applications in gas sensing, LiDAR, coherent optical communication, and other advanced fields.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"186 ","pages":"Article 112627"},"PeriodicalIF":4.6,"publicationDate":"2025-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143471546","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":"Oscillating laser welding of ultra-thick titanium alloy using new flux-cored filler wire: Process stability, microstructural evolution and mechanical properties","authors":"Naiwen Fang ,&nbsp;Zhiqiang Feng ,&nbsp;Pengbo Wu ,&nbsp;Jiutian Luo ,&nbsp;Ruisheng Huang ,&nbsp;Kai Xu ,&nbsp;Jipeng Zou ,&nbsp;Hao Cao ,&nbsp;Laibo Sun ,&nbsp;Quan Li ,&nbsp;Bintao Wu","doi":"10.1016/j.optlastec.2025.112604","DOIUrl":"10.1016/j.optlastec.2025.112604","url":null,"abstract":"<div><div>A new type of flux-cored filler wire was designed by synchronously optimizing Mo and Fe elements, and it was applied to narrow gap laser oscillating wire filler welding (NG-LOWFW) of ultra-thick titanium alloy, the effects of process parameters on the stability of welding process, microstructure and mechanical properties of welded joint were studied by experiment and numerical simulation. The results show that the oscillating laser and the liquid bridge transition mode could increase heat exchange between molten pool surface and external environment, resulting in high undercooling conditions, reduced thermal gradient, and guarantee the stability of the welding process effectively, the microstructure evolution of ultra-thick welded seam is uniform, the grain size is refined and the welding defects are restrained effectively. Moreover, Mo and Fe elements could further enhance the wetting and spreading mobility of liquid metal during welding, which contributes to the synergistic optimization of strength and toughness of ultra-thick welded joint, up to 935 MPa and 25 J. The research outcomes provide a new route for welding ultra-thick titanium alloy, which benefits further welding process and optimization.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"186 ","pages":"Article 112604"},"PeriodicalIF":4.6,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464149","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 mechanism and characteristics of laser repair of surface damage after ultra-precision grinding of monocrystalline silicon","authors":"Guoyan Sun ,&nbsp;Cui Deng ,&nbsp;Wei Hao ,&nbsp;Jianke Zhao ,&nbsp;Mingxu Fan ,&nbsp;Jiaoteng Ding ,&nbsp;Xiabin Ji","doi":"10.1016/j.optlastec.2025.112660","DOIUrl":"10.1016/j.optlastec.2025.112660","url":null,"abstract":"<div><div>The surface damage caused by ultra-precision grinding of monocrystalline silicon will affect the material performance and limit its application. In order to weaken or eliminate the surface defects and damages of monocrystalline silicon, laser repair research was carried out on the surface of monocrystalline silicon after ultra-precision grinding. The principle of laser repair of surface damage was described, and the relationship between laser damage threshold and laser power, ablation pore size and waist radius were clarified through theoretical model. A laser perforation experiment system based on grating scanning method was designed, and laser ablation pore sizes with different parameter combinations were obtained. Through analysis and calculation, it was determined that the damage threshold of monocrystalline silicon laser is 0.1188 ∼ 0.2419 J/cm². The theoretical model of laser damage threshold and the experimental results of laser perforation showed that the energy density of laser repair should be below the laser damage threshold. The experiment results of laser repair showed that the higher the laser power is, the better the surface repair effect is. Surface laser repair result was relatively good at 20mW laser power. And the laser power over 40mW will also have a negative effect on the repair effect. The nanoindentation experiment of monocrystalline silicon material was carried out, and the results showed that the laser repaired monocrystalline silicon surface had higher ultimate fracture strength and plastic deformation than the original grinding surface. The results of Raman spectrum analysis showed that laser repair can transform the amorphous structure into single crystal structure in the ultra-precision grinding monocrystalline silicon material. The laser repair method of surface damage implemented in this study provides guidance and reference for the suppression and removal of surface damage of monocrystalline silicon and other hard-brittle materials.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"186 ","pages":"Article 112660"},"PeriodicalIF":4.6,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143471474","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}