Article
Engineering, Electrical & Electronic
Haitao Li, Yujie Chen, Yan Wang, Hang Zhou, Hongbin Yu
Summary: A novel compact focus tunable liquid-filled lens using electromagnetic actuation method is presented. It incorporates a specially designed elastic membrane with an annular ridge structure and non-uniform thickness contour for actuator integration and improving optical quality. The lens has bidirectional, wide-range focus tuning capability due to the adoption of a custom-designed moving coil type electromagnetic actuator and a refractive index matching strategy. The lens is fabricated using a combination of injection molding and 3D printing, and it shows symmetric focal length tuning and reduced spherical aberration in experiments.
SENSORS AND ACTUATORS A-PHYSICAL
(2023)
Article
Chemistry, Analytical
Woojun Han, Jinsoo Jeong, Jaisoon Kim, Sun-Je Kim
Summary: This study proposes a theoretical method for reducing multiple monochromatic aberrations using a flat metalens doublet, which is validated through ray tracing simulations. The theoretical relationship between the Abbe sine condition and the generalized Snell's law is revealed in the doublet system. Minimization conditions for astigmatism and field curvature are derived from the Abbe aplanat design. By semi-analytically optimizing the metalens doublet, a compact and practical-level meta-microscope objective lens is realized for a target wavelength. The proposed method also addresses the reduction of lateral chromatism for an additional wavelength. The design freedom and fundamental limits of the system are rigorously analyzed and verified. It is anticipated that this method will offer unprecedented practical opportunities for the design of advanced compact microscopic imaging or sensing systems.
Article
Engineering, Electrical & Electronic
Junhyeok Jang, Gun-Yeal Lee, Youngjin Kim, Changhyun Kim, Yoonchan Jeong, Byoungho Lee
Summary: A framework for designing dispersion-engineered metasurfaces is proposed to correct monochromatic and chromatic aberrations simultaneously. A novel metasurface doublet with a wide field-of-view and broadband operation is numerically demonstrated.
IEEE PHOTONICS JOURNAL
(2023)
Article
Optics
Yuming Wang, Youshan Qu, Hui Zhao, Xuewu Fan
Summary: This study describes the design and implementation of an asymmetric Czerny-Turner ultra-wide spectral range achromatic echelle spectrometer. The spectrometer uses an off-axis parabolic mirror to obtain collimated light without aberrations, and utilizes gratings and dispersive prisms to acquire two-dimensional images containing spectral information. Suitable detectors and coaxial focusing lenses are selected and designed to minimize aberration. The simulation analysis shows that the system has good spectral resolution.
Article
Multidisciplinary Sciences
Amirhossein Fallah, Ahmad Kalhor, Leila Yousefi
Summary: Designing invisibility cloaks has always been a fascinating field of research, and metasurface-based carpet cloaks have gained attention for their lower loss and easier fabrication. However, their performance is dependent on the incident angle, making it challenging to design a carpet cloak that renders objects invisible for a wide range of angles. This paper presents a metasurface-based carpet cloak developed using the Particle Swarm Optimization algorithm and a trained neural network, capable of operating for a wide range of incident angles. Numerical analysis shows that the designed cloak performs well for incident angles ranging from 0 to 65 degrees.
SCIENTIFIC REPORTS
(2023)
Article
Optics
Thomas Fuhrmann
Summary: This study introduces an innovative method for minimizing spherical aberrations of lenses by combining two identical spherical convex lenses at an optimal distance, achieving a compensatory effect on the radial refractive power deviation.
OPTICAL ENGINEERING
(2022)
Article
Optics
Dipanjan Chakraborty, Rosen Georgiev, Sinead Aspell, Vincent Toal, Izabela Naydenova, Dervil Cody, Suzanne Martin
Summary: Theoretical modeling has been used to calculate the holographic recording beam angles required to produce a Volume Holographic Optical Element for any defined input and output beam angles. Experimental validation of the model was done to confirm the precision of the recording of desired grating structures.
Article
Multidisciplinary Sciences
Luzhao Sun, Zihao Wang, Yuechen Wang, Liang Zhao, Yanglizhi Li, Buhang Chen, Shenghong Huang, Shishu Zhang, Wendong Wang, Ding Pei, Hongwei Fang, Shan Zhong, Haiyang Liu, Jincan Zhang, Lianming Tong, Yulin Chen, Zhenyu Li, Mark H. Rummeli, Kostya S. Novoselov, Hailin Peng, Li Lin, Zhongfan Liu
Summary: The authors developed a chemical vapor deposition method for synthesizing twisted bilayer graphene with controllable angles. By employing a hetero-site nucleation strategy, they successfully prepared bilayer graphene with twist angles ranging from 0 degrees to 30 degrees, demonstrating high-quality and improved performance for potential applications in fundamental research and practical use.
NATURE COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Xin Zhang, Yanwen Hu, Xiliang Zhang, Siqi Zhu, Hao Yin, Zhen Li, Zhenqiang Chen, Shenhe Fu
Summary: This article introduces a new working mechanism for flat lens design, called a global phase-modulation mechanism, and demonstrates the potential applications of multifunctional flat lenses.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Optics
Vijay Kumar Gowda, Sabitha Gauni, K. Gurushankar, Vivek Maik
Summary: This research proposes a unique optical design with reduced and optimized lens elements to maintain high output quality in camera devices. The proposed design is evaluated using optical simulator analysis, and it outperforms the existing imaging system in both qualitative and quantitative terms.
Article
Optics
Danyang Wang, Degang Hu, Yanwu Zhou, Licun Sun
Summary: In this study, a focus-tunable liquid cylindrical lens based on electrowetting was designed and fabricated. By changing the supplied voltage, the proposed liquid cylindrical lens can serve as both a converging and diverging lens with a fast response time. By combining it with a fixed cylindrical lens, a cylindrical lens system with an arbitrary focal length can be realized.
Article
Engineering, Electrical & Electronic
Abdulrahman Ahmed Ghaleb Amer, Syarfa Zahirah Sapuan, Adel Y. Ashyap
Summary: This work introduces a miniaturized metasurface energy harvester that efficiently captures incident electromagnetic power at 5.54 GHz with a wide incident angle. The proposed design achieves high conversion efficiency through optimized structure and impedance matching.
JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS
(2023)
Article
Optics
Leonid L. Doskolovich, Dmitry A. Bykov, Evgeni A. Bezus, Grigoriy Greisukh
Summary: The method explores designing stigmatic lenses that implement required ray mappings, simplifying calculations to solving ordinary differential equations by linking the angular coordinates of rays at image points with those from the object. Examples include designing stigmatic lenses satisfying various conditions.
Article
Engineering, Electrical & Electronic
Li-Zhao Song, Maral Ansari, Pei-Yuan Qin, Stefano Maci, Jia Du, Y. Jay Guo
Summary: High aperture efficiency 2-D multibeam gradient index lenses are developed in this work. New methods based on bifocal analysis are employed to determine the refractive index profile of the lens and enable independent wide-angle multibeam radiations. The lenses achieve stable multibeam radiation patterns in a wide frequency range with high beam coverage and aperture efficiency.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Multidisciplinary Sciences
Cheng-Yu Lu, Chin-Chien Chung, Ta-Jen Yen, Tsung-Yu Huang
Summary: The study presents a novel approach of using a periodic seed layer and oblique deposition method to fabricate a stochastically-distributed oblique-flat-sheet metamaterial perfect absorber (MPA) with increased absorption bandwidth and tolerance to high angle-incidence. Simulation and measurement results both demonstrate satisfactory absorption performance of the MPA.
SCIENTIFIC REPORTS
(2021)
