Optics & Laser Technology最新文献

{"title":"Real-time estimation of blood oxygenation parameters from human foot sole during leg elevation: A preliminary study with diffuse reflectance spectroscopy","authors":"Ajay Kumar, Viney Lohchab, Dnyandeo Pawar, Vimal Someshwar, Vikas Mathe, Sudhir Husale, Rajesh Kanawade","doi":"10.1016/j.optlastec.2024.111706","DOIUrl":"https://doi.org/10.1016/j.optlastec.2024.111706","url":null,"abstract":"This study investigated the applicability of diffuse reflectance spectroscopy (DRS) for real-time and non-invasive measurement of blood oxygenation parameters (BOPs) such as reduced hemoglobin (RHb), oxyhemoglobin (HbO), and oxygen saturation (SO) from human foot sole during leg elevation. Seventeen (17) healthy male subjects aged between 21 to 39 years were included in this study. Diffuse reflectance spectra were recorded from measurement sites namely the 5th metatarsal, ball of great joint, calcaneum, and great toe of the human foot sole w.r.t. leg elevation angles such as 0, 15, 30, 45, and 60, respectively. The localized BOPs were derived from the recorded spectra. In addition, blood hemodynamic parameters (BHPs) such as heart rate (HR), SO, perfusion index (PI), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were also measured for each elevating angle. To study and assess the changes in BOPs and BHPs w.r.t. leg elevation, a One-way ANOVA test followed by a Tukey HSD post-hoc test was performed. We observed a statistically significant increase in RHb (p < 0.001) and a decrease in HbO (p < 0.001) after 45° of leg elevation, however, there was no statistically significant difference in SO (p = 0.74) and HR (p = 0.84) for each measurement site w.r.t. leg elevation, respectively. Furthermore, PI (p < 0.01), ankle SBP (p < 0.001) and DBP (p < 0.001) were decreased w.r.t. leg elevation. The obtained results are in agreement with the literature. The preliminary results suggest that DRS has the potential for real-time estimation of BOPs from the local sites of healthy human foot soles during leg elevation. Thus, it opens the possibility of DRS to monitor and evaluate the diagnosis and treatment of ischemia and edema during leg elevation of patients through BOPs measurement.","PeriodicalId":19597,"journal":{"name":"Optics & Laser Technology","volume":"171 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142219933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regulating thermal management by a CsPbClBr2/Ag hybrid microcavity for stable room temperature blue lasing with low threshold","authors":"Shulei Li, Zhenxu Lin, Quantong Deng, Fu Deng, Mingcheng Panmai, Junying Chen, Yuheng Mao, Shimei Liu, Jun Dai, Yunbao Zheng, Rui Huang, Sheng Lan","doi":"10.1016/j.optlastec.2024.111723","DOIUrl":"https://doi.org/10.1016/j.optlastec.2024.111723","url":null,"abstract":"Realization of long-term stable lasing from all-inorganic perovskite supercrystals is highly desirable for practical applications in optoelectronic devices. However, lasing from perovskite supercrystals excited by continuous wave laser light remains a challenge due to the photoluminescence degradation induced by thermal accumulation. Here, we report highly stable lasing with low threshold fom a CsPbClBr supercrystal placed on a thin Ag film, which form a CsPbClBr/Ag microcavity, by managing the thermal distribution inside the CsPbClBr supercrystal. Combined numerical simulations and lifetime measurements, the localized electric field in such a hybrid microcavity leads to a spatially localized temperature distribution, which plays a crucial role in suppressing the thermal accumulation on the surface and in eliminating non-radiative recombination defects. The effective thermal management in the hybrid microcavity renders highly stable lasing with low threshold under the irradiation of continuouw wave laser light. Our findings provide a feasible and universal approach to the development of long-term stable perovskite laser.","PeriodicalId":19597,"journal":{"name":"Optics & Laser Technology","volume":"145 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142219974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Broadband multiple resonant metasurface for mixture surface-enhanced infrared absorption based on polarization-sensitive folded nanoantennas","authors":"Si Luo, Yunlian Ding, Meiyan Pan, Rujun Zhou, Haichao Han, Zijun Liao, Daru Chen","doi":"10.1016/j.optlastec.2024.111685","DOIUrl":"https://doi.org/10.1016/j.optlastec.2024.111685","url":null,"abstract":"Multiple resonant metasurfaces for mixture component detection by surface-enhanced infrared absorption in a broadband spectrum region are still highly desirable. This paper presents a polarization-sensitive multi-resonant broadband metasurface in the mid-infrared (MIR) region based on an odd symmetric folded antenna array. Six major resonant modes are effectively excited in 6–15 μm covering the absorption peak of multiple gases and biomolecules. In addition, the calculation indicates the maximum electric field intensity enhancement reaches 3607 and the average electric enhancement factors are dominantly amplified to a maximum of 75.08. The excited multiple hotspots provide more spatial overlap with analytes and would be beneficial for label-free detection. Moreover, owing to the contributions of the intrinsic phonons and polaritons in the ENZ material, the spectroscopy features are relatively stable when changing the geometry parameters and the incident angles, allowing more fabrication tolerance and experiment flexibility. Furthermore, the multiple resonant metasurface is also effectively enabled under orthogonal circular polarizations. Finally, the sensing abilities of the designed metasurface for polyethylene terephthalate and isopropanol molecules have been computationally validated. These results indicate the potential for nanophotonic detection and mixture spectroscopy analysis.","PeriodicalId":19597,"journal":{"name":"Optics & Laser Technology","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142219976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on accurate analysis of coal quality using NIRS-XRF fusion spectroscopy in complex coal type scenarios","authors":"Jiaxuan Li, Rui Gao, Yan Zhang, Lei Zhang, Lei Dong, Weiguang Ma, Wangbao Yin, Suotang Jia","doi":"10.1016/j.optlastec.2024.111734","DOIUrl":"https://doi.org/10.1016/j.optlastec.2024.111734","url":null,"abstract":"Coking coal in coal chemical enterprises presents a challenge due to its diverse types, wide sources, and variable quality, influenced by varying degrees of metamorphism and physicochemical properties. These differences not only impact coal quality but also hinder accurate analysis. Rapid and precise coal quality detection amidst diverse coal types is crucial for maintaining stable production and ensuring coke quality. This study employs near-infrared spectroscopy (NIRS) and X-ray fluorescence spectroscopy (XRF) fusion spectroscopy analysis, along with Principal Component Analysis (PCA) and t-Distributed Stochastic Neighbor Embedding (t-SNE), for data dimensionality reduction and visualization to devise a coal sample classification strategy. Subsequently, Support Vector Machine (SVM) is employed for automatic coal sample classification based on this strategy. Finally, Partial Least Squares Regression (PLSR) is used to establish regression models and evaluate their performance in predicting coal quality. Results show that classified regression model achieves values of 0.9987, 0.9955, and 0.9997 for ash content, volatile matter, and sulfur content, with corresponding root mean square error for prediction () of 0.31 %, 1.34 %, and 0.05 %, and the mean absolute relative error for prediction () of 2.48 %, 3.58 %, and 3.57 %, respectively. Compared to the unclassified model, there is a significant enhancement in prediction accuracy. The classification and modeling method proposed herein effectively improve the accuracy of coal quality analysis in complex coal type scenarios, crucial for industries like coal chemical engineering to enhance production efficiency and optimize coal resource utilization.","PeriodicalId":19597,"journal":{"name":"Optics & Laser Technology","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142219972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Generation of atto-zeptosecond X-rays through cross-collision between relativistic electron and tightly focused intense laser pulse","authors":"Qingyu Yang, Youwei Tian, Yizhang Li, Yubo Wang","doi":"10.1016/j.optlastec.2024.111719","DOIUrl":"https://doi.org/10.1016/j.optlastec.2024.111719","url":null,"abstract":"The generation of ultrashort pulses is a hot topic in ultrafast physics. In the framework of classical electrodynamics, the process of nonlinear cross Thomson scattering which involves sideways radiation generation by a high-energy single electron cross-colliding with a tightly focused circularly polarized intense laser pulse is investigated through numerical simulation. For spatial limited tightly focused laser pulses, the laser delay time determines the position the electron interacts with, so precise control of the laser delay time to ensure the electron collides with the laser center is the key to obtaining high-power radiation. Through the research on the time evolution of electron radiation, it is found that the nonlinear cross Thomson scattering power is related to the coupling of electron velocity and its acceleration, where the increase of the electron velocity is critical to obtaining higher-power radiation. For off-axis electrons, the increase in deviation distance mainly leads to a decrease in radiation power, rather than pulse width and central photon energy. For low initial energy electrons, the asymmetry brought about by cross-collisions will improve the spatial collimation. For high-energy electrons, the asymmetry is weakened but the spatial collimation is enhanced. Using a single electron with an initial energy of 100 MeV and a laser pulse with an intensity of about , hard -rays can be generated. This study reveals part of the mechanism of nonlinear cross Thomson scattering and provides the theoretical basis and parameter suggestions for the design of the next generation ultrashort high-energy pulse generator.","PeriodicalId":19597,"journal":{"name":"Optics & Laser Technology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142219975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synergizing deep learning and phase change materials for four-state broadband multifunctional metasurfaces in the visible range","authors":"Md. Ehsanul Karim, Md. Redwanul Karim, Sajid Muhaimin Choudhury","doi":"10.1016/j.optlastec.2024.111730","DOIUrl":"https://doi.org/10.1016/j.optlastec.2024.111730","url":null,"abstract":"In this article, we report, for the first time, broadband multifunctional metasurfaces with more than four distinct functionalities. The constituent meta-atoms combine two different phase change materials, and in a multi-stage configuration. Finite-difference time-domain simulations demonstrate a broadband reflection amplitude switching between the four states in visible range due to the enhanced cavity length modulation effect from the cascaded Fabry–Perot cavities, overcoming the inherent small optical contrast between the phase change material (PCM) states. This, along with the reflection phase control between the four states, allows us to incorporate both amplitude and phase-dependent properties in the same metasurface — achromatic deflection, wavelength beam splitting, achromatic focusing, and broadband absorption, overcoming the limitations of previous functionality switching mechanisms for the visible band. We have used a Tandem Neural network-based inverse design scheme to ensure the stringent requirements of different states are realized. We have used two forward networks for predicting the reflection amplitude and phase for a meta-atom within the pre-defined design space. The excellent prediction capability of these surrogate models is utilized to train the reverse network. The inverse design network, trained with a labeled data set, is capable of efficiently navigating through the vast parametric space to produce the optimized meta-units given the desired figure-of-merits in terms of reflection amplitude and phase for the four states. The optical characteristics of two inverse-designed metasurfaces have been evaluated as test cases for two different sets of design parameters in the four states. Both structures demonstrate the four desired broadband functionalities while closely matching the design requirements, suggesting their potential in visible-range portable medical imaging devices. The findings of this work will open new horizons for active metasurface design with broadband complex multifunctionalities in different spectral bands.","PeriodicalId":19597,"journal":{"name":"Optics & Laser Technology","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142219973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Demodulation algorithm of low coherent heterodyne interference signal for axial clearance measurement of rotating machinery","authors":"Xing Fan, Yilin Ren, Peng Zhang, Xianming Liu, Xiaohua Lei, Weimin Chen","doi":"10.1016/j.optlastec.2024.111714","DOIUrl":"https://doi.org/10.1016/j.optlastec.2024.111714","url":null,"abstract":"The time-domain low coherent heterodyne interference axial clearance measurement method has the challenges of small range and low precision in the clearance measurement of rotating machinery. An axial clearance demodulation algorithm based on the windowed power spectrum density transform (WPSD) is proposed. Based on the characteristics of low coherent heterodyne interference signal, the relationship model between window width and rotating structure motion parameters (amplitude of axial clearance change, rotor speed) is constructed, and the optimal window width mathematical model is obtained. The axial clearance measurement experiments are completed under different axial clearance measurement distances based on an experimental clearance platform, different rotor speeds and different axial clearance variation amplitudes. The experimental results show that the absolute error of the axial clearance reconstruction signal is less than 17 μm and the relative error is less than 4.8 % when the axial clearance measurement distance is 2.1 mm ∼ 11.3 mm, the rotor speed is in the range of 6000 rad/min ∼ 12000 rad/min, and the variation of axial clearance is in the range of 150 μm ∼ 350 μm. The experimental and simulation results are basically consistent.","PeriodicalId":19597,"journal":{"name":"Optics & Laser Technology","volume":"72 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142219980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In-situ observation of CO gas bubble behavior in molten pool during direct laser deposition of WC-Co cermet material","authors":"Takuto Yamaguchi, Keigo Tanaka, Takeshi Suyama","doi":"10.1016/j.optlastec.2024.111561","DOIUrl":"https://doi.org/10.1016/j.optlastec.2024.111561","url":null,"abstract":"Laser cladding of WC-Co cermet material is a promising means of improving the wear resistance of metal products. Layer-by-layer processing of laser cladding, also designated as laser directed energy deposition and laser metal deposition, is attracting attention as an alternative manufacturing process of cermet materials for conventional powder metallurgy processing. Laser cladding of WC-Co has constraints on its practical use because a clad bead of WC-Co often includes numerous defects such as cracks and pores. Various factors cause pores in clad beads. Therefore, establishing a method for restraining them is difficult. Obtaining dense clad beads having few pores requires the elucidation of behaviors of gas bubbles: the precursors of pores. Nevertheless, observations inside molten pools are difficult, thereby complicating the characterization of gas bubble behavior.","PeriodicalId":19597,"journal":{"name":"Optics & Laser Technology","volume":"148 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141933854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A filled-enhanced high-sensitivity optical fiber temperature sensor","authors":"Yin-song Zhao, Lu Cai, Jia-bao Xie, Gang Yang, Yong Zhao","doi":"10.1016/j.optlastec.2024.111543","DOIUrl":"https://doi.org/10.1016/j.optlastec.2024.111543","url":null,"abstract":"In this paper, a temperature sensing structure comprising single-mode fiber (SMF) and dual-core single-side hole fiber (DCSHF) is introduced and demonstrated to enhance temperature sensing performance based on modal interference. The biased air hole of DCSHF minimizes temperature-induced variations in the effective refractive index of the core mode, resulting in high sensitivity of temperature sensing. For further enhancement, alcohol with a high thermo-optical coefficient is introduced into the air hole, while barium titanate microsphere is innovatively inserted as coupling factor to enhance mode coupling efficiency. The experimental results prove that the maximum sensitivity of this sensor can reach up to −5.57 nm/°C. The sensor offers advantages such as simple preparation, high sensitivity, excellent repeatability, rapid response, and remarkable stability, suggesting wide-ranging potential applications in temperature sensing.","PeriodicalId":19597,"journal":{"name":"Optics & Laser Technology","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141933855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hybrid laser welding and brazing for controlling intermetallic compounds in Al/Cu dissimilar joint","authors":"Weizhe Du, Xuting Huang, Min Zheng, Rongshi Xiao, Jiejie Xu, Ting Huang","doi":"10.1016/j.optlastec.2024.111559","DOIUrl":"https://doi.org/10.1016/j.optlastec.2024.111559","url":null,"abstract":"Micro-welding of Al and Cu foils is increasing used in various industries, particularly in the production of battery components for electric vehicles. However, direct fusion welding of Al and Cu may compromise joint mechanical properties due to the formation of brittle intermetallic compounds (IMC). Consequently, strategies for controlling IMC to enhance joint mechanical properties have received significant research attention. In this study, lap welds of 1050 Al foil and T2 Cu foil (both 200 μm thick) are achieved using a single-mode fiber laser equipped with a scanning galvanometer. This setup enables spatial power modulation for laser spot welding via beam spiral scanning. Notably, laser fusion welding occurs along the laser beam scanning path, while laser weld-brazing is achieved through heat conduction in the spiral spacing between the adjacent scanning paths, resulting in a hybrid joint with alternated fused and brazed areas. The laser weld-brazing areas expand the effective connection area of the joint, improving its load-bearing capacity while effectively controlling IMC compared to fusion joints. The screw-type hybrid joints exhibit excellent mechanical properties, with a maximum tensile strength of 140 MPa. Experimental and simulation results indicate the mechanism for hybrid joint formation and improvement in mechanical properties. This study provides an effective strategy for regulating joint microstructure to mitigate the negative influence of IMC.","PeriodicalId":19597,"journal":{"name":"Optics & Laser Technology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141933857","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}