Results 131 to 140 of about 10,131,834 (310)

Review on vortex beams with low spatial coherence

Advances in Physics: X, 2019
Vortex beams with helical phase, carrying phase singularity and orbital angular momentum, have attract great attention in the past decades due to their wide applications in optical communications, optical manipulation, super-resolution imaging and so on.
Xianlong Liu, Jun Zeng, Yangjian Cai
doaj   +1 more source

Improving the Robustness of Visual Teach‐and‐Repeat Navigation Using Drift Error Correction and Event‐Based Vision for Low‐Light Environments

Advanced Robotics Research, EarlyView.
Visual teach‐and‐repeat (VTR) navigation allows robots to learn and follow routes without building a full metric map. We show that navigation accuracy for VTR can be improved by integrating a topological map with error‐drift correction based on stereo vision.
Fuhai Ling, Ze Huang, Tony J. Prescott
wiley   +1 more source

Relaying techniques for free space optical communications

, 2019
Despite the major advantages of FSO technology and variety of its application areas, its widespread use has been hampered by its rather disappointing link reliability particularly in long ranges due to atmospheric turbulence-induced fading.
Aminikashani, Mohammadreza, Mohammadreza Aminikashani, Murat Uysal, Uysal, Murat   +3 more
core   +1 more source

Waveguide Photoactuators: Materials, Fabrication, and Applications

Advanced Robotics Research, EarlyView.
Waveguide photoactuators convert guided light into mechanical motion. Their tethered‐flexible design enables minimally invasive surgery and confined‐space robotics. This review aims to guide materials selection, device design, and system integration, accelerating the transition of waveguide photoactuators from laboratory prototypes to versatile ...
Minjie Xi, Hemin Pan, Yang Zong, Yongfeng Mei, Jizhai Cui   +4 more
wiley   +1 more source

A Low‐Cost, Handheld Optical Stiffness Sensor for Minimally Invasive Surgery

Advanced Robotics Research, EarlyView.
A novel handheld stiffness sensor is presented for real‐time tissue stiffness characterization. By simultaneously sensing contact force and tissue deformation, the device enables accurate stiffness quantification without requiring precise manual control. This approach offers a promising solution for intraoperative tumor detection and minimally invasive
Qianyu Ma, Ruxiang Jiang, Kaspar Althoefer, Nicolas Herzig, Hareesh Godaba   +4 more
wiley   +1 more source

Photonic Time Crystals and Time‐Varying Electromagnetic Metamatter: A New Direction for Ultrafast Tunable Photonic and Microwave Materials and Devices

Advanced Science, EarlyView.
Photonic time crystals (PTCs) are systems in which electromagnetic parameters are modulated periodically in time, producing momentum bandgaps via temporal scattering rather than spatial Bragg processes. This review examines the theoretical frameworks, modeling, and computational tools for time‐varying media, and summarizes experimental demonstrations ...
Ranjan Kumar Patel, Shriram Ramanathan, Ronald P. Jenkins, Michael J. Carter   +3 more
wiley   +1 more source

Conceptualising quality early childhood education: Learning from young children in Brazil and South Africa through creative and play‐based methods

British Educational Research Journal, EarlyView., 2023
Abstract Early childhood has increasingly been acknowledged as a vital time for all children. Inclusive and quality education is part of the United Nations Sustainable Development Goals, with the further specification that all children have access to quality pre‐primary education.
Laura H. V. Wright, Irene Rizzini, Malibongwe Gwele, Lynn McNair, Cristina Laclette Porto, Marsha Orgill, E. Kay M. Tisdall, Malcolm Bush, Linda Biersteker   +8 more
wiley   +1 more source

Current optical technologies for wireless access [PDF]

, 2009
The objective of this paper is to describe recent activities and investigations on free-space optics (FSO) or optical wireless and the excellent results achieved within SatNEx an EU-framework 6th programme and IC 0802 a COST action.
Sheikh Muhammed, S., Ghassemlooy, Zabih, Javornik, Tomaz, Kandus, Gorazd, Awan, Muhammad, Brandl, P., Capsoni, Carlo, Leitgeb, Erich, Nebuloni, R.   +8 more
core  

Photonic‐Enabled Energy‐Efficient Transparent Neuromorphic Computing Devices: A Review

Advanced Science, EarlyView.
Transparent photonic neuromorphic computing devices merge optics and brain‐inspired computing to overcome von Neumann bottlenecks with ultrafast, low‐energy processing. By exploiting transparent oxides, 2D materials, phase‐change materials, and hybrid heterostructures, these platforms enable photonic synapses, memory, and logic for see‐through edge ...
Shuvaraj Ghosh, Ki‐bum Lee, Junghyeon Lee, Seunghee Cho, Malkeshkumar Patel, Hangfei Li, Yu Wen, Ye Zhou, Joondong Kim   +8 more
wiley   +1 more source

Multi-Actuator Lens Systems for Turbulence Correction in Free-Space Optical Communications

Photonics
The implementation of efficient free-space channels is fundamental for both classical and quantum free-space optical (FSO) communication. This can be challenging for fiber-coupled receivers, due to the time variant inhomogeneity of the refractive index ...
Matteo Schiavon, Antonio Vanzo, Kevin Campaci, Valentina Marulanda Acosta, Stefano Bonora   +4 more
doaj   +1 more source