Article
Optics
Yufeng Tao, Bingjie Wang, Weijie Xu, Xuejiao Wang, Yunpeng Ren, Zhiduo Xin, Kun He, Xiangjun Ma, Guangjian He, Chunsan Deng, Zijie Dai
Summary: The ion-interactive semi-conductive hydrogel is a promising optoelectronic material with desirable electrical conductivity, optical clarity, and switchable dielectric properties. However, the development of actively modulated terahertz (THz) devices using hydrogel is still in its early stages. In this study, a scalable high-throughput picosecond laser system is used to rapidly tailor hydrogel into ion-interactive dielectric metasurfaces (IDMs). These IDMs possess negative permittivity, tunable time/frequency modulation, and high-consistency geometries for specific THz wave manipulations.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
Jian-wei Ma, Hui Zhang, Tao Ye, Song-hong-ze Wang, Zhi-Ben Yang, Zhen-yuan Jia
Summary: This study demonstrates the effect of variable cross-section microgrooves on drag reduction through fluid simulation and proposes a novel method called moving zoom laser processing for microgroove fabrication. A continuous wave laser ablation model is established and a planning method for process parameters is introduced. Experimental results verify the feasibility and effectiveness of the proposed method.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
K. Monisha, S. M. Shariff, A. Sekar, Ravi Raju, J. Manonmani, J. Senthilselvan
Summary: This study fabricates a superhard titanium boride coating on titanium surface using high power diode laser alloying. Amorphous boron is transformed into crystalline boron by high-power laser interaction and rapidly combines with titanium to form titanium boride precipitates. The laser borided coating exhibits dendrites and whisker-like microstructures, with microhardness ranging from 800-1600 HV0.2 and extreme hardness of 3800-4700 HV0.2 in some regions of boron precipitates. The formation of TiB and TiB2 phases shows a high negative Gibbs free energy and an activation energy of 140 kJ/mol, indicating the spontaneity of the reaction. The laser borided coating with TiB and TiB2 phases has potential for surface engineering applications.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
Haisen Yuan, Yu Li, Jing Zhao, Ling Zhang, Wenjie Li, Yang Huang, Xingyu Gao, Qiadong Xie
Summary: An adaptive fringe projection method is proposed in this paper to solve the failure of coded fringe patterns caused by high reflectivity of measured surfaces. The method utilizes the best projection intensity strategy and coordinate mapping between camera and projection regions. It is robust, convenient, and effectively reduces mapping errors.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
Biao Chen, Y. Liu, Daping He, He Chen, Kaikai Huang, Xuanhui Lu
Summary: In this paper, we study the angular deviation and diffraction efficiency of reflection gratings in the Littrow-configuration for external cavity diode laser applications using the rigorous coupled-wave analysis method. We consider the general three-dimensional diffraction case, where the incidence plane is un-parallel with the grating vector, i.e., conical diffraction. The angular tolerance for arbitrary gratings under plane and conical diffraction is derived and presented. Furthermore, we find that selecting appropriate parameter settings can improve the angular tolerance and reflection efficiency, including the incidence angle, diffraction order, grating period, and blazed angle. We also highlight the importance of avoiding slight deviations in the grating vector from the incidence plane, as it can disrupt laser oscillation in the external cavity.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
Hee-Lak Lee, Arif Hussain, Yoon Jae Moon, Jun Young Hwang, Seung Jae Moon
Summary: The conditions for obtaining a completely connected ablated line were investigated, and it was found that a higher fluence was needed to form the ablated line properly.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
Ying Zhao, Hong Qi, Ya-Tao Ren, Ming-Jian He, Bao-Hai Gao, Wen Cheng
Summary: The reconstruction of optical parameters is of great research significance and practical value in biological tissue functional imaging, and has received increasing attention in the field of medical diagnosis and treatment. This paper proposes an improved sequential quadratic programming method to overcome the difficulties in the reconstruction process and achieve high accuracy and efficiency in estimating target parameters, with good robustness. Additionally, a time-frequency coupling model is constructed and demonstrated in a biological tissue-like medium model, showing its practical significance.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
Sunderlal Singh Sanasam, G. l. Samuel
Summary: This paper reports on the application of femtosecond laser for modifying surface wettability without significant chemical modification, by tuning the surface morphology. The study shows the ability to achieve both hydrophilicity and hydrophobicity.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
Yasemin Gundogdu, Sami Dursun, Serap Yigit Gezgin, Hamdi Sukur Kilic
Summary: Green synthesis based nanoparticle production methods and water purification techniques were used to synthesize ZnO and Ag nanoparticles, and applied in water purification. Experimental results showed that a composite photocatalyst containing 6.0 wt% Ag exhibited a 68.62% higher rate constant value in degrading methylene blue dye molecules compared to pure ZnO nanoparticles under visible light.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
Konstantinos Tsimvrakidis, Symeon I. Tsintzos, James C. Gates, Peter G. R. Smith, Ali W. Elshaari, Val Zwiller, Christos Riziotis
Summary: Optical integrated circuits are seen as a promising platform for developing robust and efficient quantum computers. The integration of multiple single photon sources in these circuits is a critical issue for scalability. This study explores the integration of quantum dots embedded in semiconductor optical nanowires in different platforms and reveals limitations and challenges due to low achievable refractive index contrast. Suitable integration approaches with adequate efficiency are demonstrated.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
Duo Yang, Jinyuan Tang, Fujia Xia, Shengyu You
Summary: This paper introduces an active design method for constructing the expected bearing capacity of a surface topography. By adjusting the roughness characteristic parameters, the desired surface bearing ratio tp(c) can be achieved. The surface height matrix that satisfies the expected tp(c) and roughness characteristic parameters is calculated using a genetic algorithm. The results show that the method is reliable and the adjustment of roughness characteristic parameters has a significant impact on the surface bearing capacity.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
Bingxu Zhang, Hui Chen, Yan Liu, Yunfei Meng, Ailin Deng, Xu Wu
Summary: This study investigates the formation of pores in laser welding using Al-Si wires with different Si contents. The results indicate that increasing the Si content in the wire leads to decreased keyhole stability and increased weld porosity. The increased Si content enhances the Reynolds number of the molten pool, making it more susceptible to external disturbances, thus decreasing the stability of the keyhole. In addition, the reduced dynamic viscosity of the molten pool increases the depth-to-width ratio of the keyhole and its opening and closing frequency, ultimately resulting in increased susceptibility to pores formation. Introducing circular oscillating laser and using response surface methodology to determine optimal parameters can control the porosity within an acceptable range.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
Xiao Du, Bing Li, Zhuo Zhao, Bingke Jiang, Yupeng Shi, Liuyi Jin, Xiao Jin
Summary: This paper introduces a method for visual anomaly detection that identifies abnormal regions using a reconstruction network and correction branch, and improves the model's predictive and discriminative capacity by utilizing ConvNeXt blocks and channel attention mechanism.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
M. Mohamed Rabik, S. Vasanth, T. Muthuramalingam
Summary: In this study, an attempt was made to improve the cutting process of diode-assisted laser beam machining using an LQR controller. The results showed that the LQR approach produced better kerf width and carbonization compared to the PID controller.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
Oscar Real-Moreno, Julio C. Rodriguez-Quinonez, Wendy Flores-Fuentes, Oleg Sergiyenko, Jesus E. Miranda-Vega, Gabriel Trujillo-Hernandez, Daniel Hernandez-Balbuena
Summary: This paper presents a novel camera calibration method for improving depth estimation accuracy in stereo vision systems. The method addresses the lens distortion issue and corrects the relative orientation of the cameras. Compared to traditional methods, it is easier to implement and more robust to varying illumination levels.
OPTICS AND LASERS IN ENGINEERING
(2024)
Article
Optics
Mohammad Jafari Eskandari, Masoud Araghchi, Hamid Daneshmand, Ali Hadipour
Summary: This work proposes a repeatable, controllable, non-contact, cost-effective, and fast method for measuring the fracture toughness of epoxy resin composites. The notches and pre-cracks for the fracture toughness test were fabricated using a steel razor blade method and a laser ablation method. The results of the laser ablation method were found to have the highest accuracy and reproducibility, with pre-cracking tips that exhibited no plastic deformation. The fracture toughness values obtained by the laser method were in accordance with ISO and ASTM standards, demonstrating their repeatability and accuracy.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
Jialang Zhang, Jinghao Wang, Junna Yao, Xinhua Jiang, Lei Gui, Siyuan Zhang, Qiwen Zhan, Anting Wang
Summary: We demonstrate a tunable spectrally-flat multi-wavelength cylindrical vector beam (CVB) fiber laser using a two-mode long-period fiber grating (TM-LPFG) and a re-circulating frequency shifter loop. The laser can produce multi-wavelength CVBs with low power variation and high purity, and exhibits excellent stability.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
Negin Piri, Erfan Memarian
Summary: Identification of polymer type is crucial in industry, but traditional methods are laborious and costly. This study introduces a clean and fast approach using optical tools to detect polymeric materials, focusing on textile fibers and yarns. Experimental observations show the potential of this method.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
Hongxiang Chang, Rongtao Su, Yuqiu Zhang, Bowang Shu, Jinhu Long, Jinyong Leng, Pu Zhou
Summary: High-speed variable-focus optics provides new opportunities for fiber laser applications in various fields. This paper investigates a non-mechanical axial focus tuning method using coherent beam combining (CBC) technique and proposes a tilt modulation assisted method to extend the tuning range.
OPTICS AND LASERS IN ENGINEERING
(2024)
Article
Optics
Yubo Ni, Shuai Fu, Chaoyang Su, Zhaozong Meng, Nan Gao, Zonghua Zhang
Summary: This paper proposes a surface adaptive fringe pattern generation method to accurately measure specular surfaces, eliminating the out-of-focus effect and improving measurement accuracy and reliability.
OPTICS AND LASERS IN ENGINEERING
(2024)
