Download or read book Gallium Nitride Light emitting Diode Enabled Visible Light Communications written by Ricardo Xavier da Graça Ferreira and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis focuses on the development, measurement and application of novel micrometre-sized light emitting diodes (micro-LEDs) based on Gallium Nitride (GaN) for visible light communications (VLC) in both free-space and guided wave configurations. The goal is to set benchmarks for LED-based wireless optical communications. An overview of the field integrating research, industry and standards is presented.A top-down approach is taken with application requirements driving development of new micro-LEDs with simultaneously increased optical power and modulation bandwidth. This was achieved by mitigating two limitations, namely current crowding and mutual device heating.Two novel techniques were developed to access pixel performance: spatially-resolved mapping of modulation bandwidth and spectral characteristics, and thermal imaging. On this basis, broad-area LEDs were used to understand the independent benefits, providing insight for the design of novel micro-LEDs. Circular segmented micro-LEDs emitting at 450nm achieved modulation bandwidths in excess of 800MHz, the highest reported for LEDs, while maintaining optical power above 2mW. In data transmission using systems with 1.8GHz bandwidth,the devices achieved 8Gbps in free-space and guided-wave operation at wavelengths of 400nm, 450nm and 520nm. Ring and half-ring micro-LEDs introduced here have shown modulation bandwidths that scale with the increase of active area and consequently optical power. Bandwidths in excess of of 600MHz were achieved at optical powers over 5mW. In data transmission using a system limited to 1GHz bandwidth, these devices achieved 7Gbps in free-space operation.

Download or read book III Nitrides Light Emitting Diodes Technology and Applications written by Jinmin Li and published by Springer Nature. This book was released on 2020-08-31 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book provides an overview of III-nitride-material-based light-emitting diode (LED) technology, from the basic material physics to the latest advances in the field, such as homoepitaxy and heteroepitaxy of the materials on different substrates. It also includes the latest advances in the field, such as approaches to improve quantum efficiency and reliability as well as novel structured LEDs. It explores the concept of material growth, chip structure, packaging, reliability and application of LEDs. With spectra coverage from ultraviolet (UV) to entire visible light wavelength, the III-nitride-material-based LEDs have a broad application potential, and are not just limited to illumination. These novel applications, such as health & medical, visible light communications, fishery and horticulture, are also discussed in the book.

Download or read book Nitride Semiconductor Light Emitting Diodes LEDs written by Jian-Jang Huang and published by Woodhead Publishing. This book was released on 2017-10-24 with total page 826 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitride Semiconductor Light-Emitting Diodes (LEDs): Materials, Technologies, and Applications, Second Edition reviews the fabrication, performance and applications of the technology, encompassing the state-of-the-art material and device development, along with considerations regarding nitride-based LED design. This updated edition is based on the latest research and advances, including two new chapters on LEDs for large displays and laser lighting. Chapters cover molecular beam epitaxy (MBE) growth of nitride semiconductors, modern metalorganic chemical vapor deposition (MOCVD) techniques, the growth of nitride-based materials, and gallium nitride (GaN)-on-sapphire and GaN-on-silicon technologies for LEDs. Nanostructured, non-polar and semi-polar nitride-based LEDs, as well as phosphor-coated nitride LEDs, are also discussed. The book also addresses the performance of nitride LEDs, including photonic crystal LEDs, surface plasmon enhanced LEDs, color tuneable LEDs, and LEDs based on quantum wells and quantum dots. Further chapters discuss the development of LED encapsulation technology and fundamental efficiency droop issues in gallium indium nitride (GaInN) LEDs. It is a technical resource for academics, physicists, materials scientists, electrical engineers, and those working in the lighting, consumer electronics, automotive, aviation, and communications sectors. - Features new chapters on laser lighting, addressing the latest advances on this topic - Reviews fabrication, performance, and applications of this technology that encompass the state-of-the-art material and device development - Covers the performance of nitride LEDs, including photonic crystal LEDs, surface plasmon enhanced LEDs, color tuneable LEDs, and LEDs based on quantum wells and quantum dots - Highlights applications of nitride LEDs, including liquid crystal display (LCD) backlighting, infra-red emitters, and automotive lighting - Provides a comprehensive discussion of gallium nitride on both silicon and sapphire substrates

Download or read book Blue Laser Diode Based Visible Light Communication and Solid State Lighting written by Amjad Ali Amjad and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this chapter, we review our recent work on blue laser diode-based visible light communication and solid-state lighting. Gallium nitride (GaN) phosphor-converted white light-emitting diodes (Pc-WLEDs) are emerging as an indispensable solid-state lighting (SSL) source for next-generation display system and the lighting industry. Together with the function of lighting, visible light communication (VLC) using Pc-WLEDs has gained increasing attention to fulfill the growing demand for wireless data communication. Practically, the low modulation response and low emitting intensity of light-emitting diodes (LED) are the drawbacks for the development of ultrahigh-speed VLC and high-quality SSL system. Blue GaN laser diode (LD) and remote phosphor-based white light can be used for both high-speed VLC and SSL simultaneously. We demonstrated a color-rendering index (CRI) of 93.8, a correlated color temperature (CCT) of 4435¬†K, and a data rate of 1.6 Gbps under NRZ-OOK modulation by an exciting blue laser diode on narrowband green,àí/red-emitting composite phosphor film. This work opens up exciting possibilities for future high-speed indoor VLC and high-quality SSL.

Download or read book III Nitride Based Light Emitting Diodes and Applications written by Tae-Yeon Seong and published by Springer. This book was released on 2017-05-18 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt: The revised edition of this important book presents updated and expanded coverage of light emitting diodes (LEDs) based on heteroepitaxial GaN on Si substrates, and includes new chapters on tunnel junction LEDs, green/yellow LEDs, and ultraviolet LEDs. Over the last two decades, significant progress has been made in the growth, doping and processing technologies of III-nitride based semiconductors, leading to considerable expectations for nitride semiconductors across a wide range of applications. LEDs are already used in traffic signals, signage lighting, and automotive applications, with the ultimate goal of the global replacement of traditional incandescent and fluorescent lamps, thus reducing energy consumption and cutting down on carbon-dioxide emission. However, some critical issues must be addressed to allow the further improvements required for the large-scale realization of solid-state lighting, and this book aims to provide the readers with details of some contemporary issues on which the performance of LEDs is seriously dependent. Most importantly, it describes why there must be a breakthrough in the growth of high-quality nitride semiconductor epitaxial layers with a low density of dislocations, in particular, in the growth of Al-rich and In-rich GaN-based semiconductors. The quality of materials is directly dependent on the substrates used, such as sapphire and Si, and the book discusses these as well as topics such as efficiency droop, growth in different orientations, polarization, and chip processing and packaging technologies. Offering an overview of the state of the art in III-Nitride LED science and technology, the book will be a core reference for researchers and engineers involved with the developments of solid state lighting, and required reading for students entering the field.

Download or read book Visible Light Communications written by Xin Lin and published by Springer Nature. This book was released on with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Introduction to Optical Wireless Mobile Communication written by Harald Haas and published by Artech House. This book was released on 2021-09-30 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of the optical spectrum for wireless communications has gained significant interest in recent years. Applications range from low-rate simplex transmission links using existing embedded CMOS cameras in smartphones, referred to as optical camera communications (OCC), mobile light fidelity (LiFi) networking in homes, offices, urban and sub-sea environments to free-space gigabit interconnects in data centers and point-to-point long-range wireless backhaul links outdoors and in space. This exciting book focuses on the use of optical wireless communications (OWC) for mobile use cases. The book discusses existing conventional radio frequency (RF)-based wireless access technology and presents the challenges that can impact the requirements of the future wave of new wireless services in the context of artificial intelligence (AI) driven autonomous systems and machine-type communications. The relationship between visible light communications (VLC) and light fidelity (LiFi), is explored, and the major advantages of VLC and LiFi such as security and data density, and discuss existing research challenges are also introduced. Channel modeling techniques are provided for mobile multiuser scenarios, and will introduce key building blocks to achieve LiFi cellular networks achieving orders of magnitude improvements of area spectral efficiency compared to state-of-the-art. Challenges that arise from moving from a static point-to-point visible light link to a LiFi network that is capable of serving hundreds of mobile and fixed nodes are discussed. An overview of recent standardization activities and the commercialization challenges of this disruptive technology is also provided.

Download or read book Optical Wireless Communications written by Z. Ghassemlooy and published by CRC Press. This book was released on 2019-04-30 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 2nd Edition of Optical Wireless Communications: System and Channel Modelling with MATLAB® with additional new materials, is a self-contained volume that provides a concise and comprehensive coverage of the theory and technology of optical wireless communication systems (OWC). The delivery method makes the book appropriate for students studying at undergraduate and graduate levels as well as researchers and professional engineers working in the field of OWC. The book gives a detailed description of OWC, focusing mainly on the infrared and visible bands, for indoor and outdoor applications. A major attraction of the book is the inclusion of Matlab codes and simulations results as well as experimental test-beds for free space optics and visible light communication systems. This valuable resource will aid the readers in understanding the concept, carrying out extensive analysis, simulations, implementation and evaluation of OWC links. This 2nd edition is structured into nine compact chapters that cover the main aspects of OWC systems: History, current state of the art and challenges Fundamental principles Optical source and detector and noise sources Modulation, equalization, diversity techniques Channel models and system performance analysis Visible light communications Terrestrial free space optics communications Relay-based free space optics communications Matlab codes. A number of Matlab based simulation codes are included in this 2nd edition to assist the readers in mastering the subject and most importantly to encourage them to write their own simulation codes and enhance their knowledge.

Download or read book Visible Light Communication written by Suseela Vappangi and published by CRC Press. This book was released on 2021-08-10 with total page 503 pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of visible light communication (VLC) has diverse applications to the end user including streaming audio, video, high-speed data browsing, voice over internet and online gaming. This comprehensive textbook discusses fundamental aspects, research activities and modulation techniques in the field of VLC. Visible Light Communication: A Comprehensive Theory and Applications with MATLAB® discusses topics including line of sight (LOS) propagation model, non-line of sight (NLOS) propagation model, carrier less amplitude and phase modulation, multiple-input-multiple-output (MIMO), non-linearities of optical sources, orthogonal frequency-division multiple access, non-orthogonal multiple access and single-carrier frequency-division multiple access in depth. Primarily written for senior undergraduate and graduate students in the field of electronics and communication engineering for courses on optical wireless communication and VLC, this book: Provides up-to-date literature in the field of VLC Presents MATLAB codes and simulations to help readers understand simulations Discusses applications of VLC in enabling vehicle to vehicle (V2V) communication Covers topics including radio frequency (RF) based wireless communications and VLC Presents modulation formats along with the derivations of probability of error expressions pertaining to different variants of optical OFDM

Download or read book High Performance III nitride Light emitting Diodes for Visible Light Communications and Micro displays written by Shuailong Zhang and published by . This book was released on 2015 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt: III-nitride micro-pixellated light-emitting diodes (micro-LEDs) are a novel format of light source capable of generating micro-scale, spatially and temporally-controllable light patterns. These devices consist of arrays of LED pixels with diameters in the range of 1 μm to 100 μm and emit light across the ultraviolet-blue-green-red part of the spectrum. In addition, compared with conventional broad-area LED devices, micro-LEDs show improved device performance in many aspects, such as high output power densities and the capability to withstand high injection current densities. For these reasons, micro-LEDs allow the study of interesting LED properties in regimes not accessible to conventional broad-area LEDs and also a wide range of novel LED applications. The research work presented in this thesis focuses on the novel applications of micro-LEDs in visible light communications (VLC) and micro-displays. Due to a reduced current crowding effect and superior thermal management capabilities, micro-LEDs can be driven at very high current densities, resulting in high modulation bandwidths of the devices. For this reason, optical data transmission was demonstrated from individual micro-LED pixels at bit rates of up to 1 Gbit/s using a high-speed probe under a binary amplitude modulation scheme. To make a more practical VLC system, micro-LED devices were integrated with specifically-designed complementary metaloxide-semiconductor (CMOS) electronics, which allow individual micro-LED pixels to be conveniently controlled via a simple computer interface. Such CMOS-controlled micro-LED devices have been demonstrated for data transmission at bit rates of up to 512 Mbit/s by modulating a single CMOS/micro-LED pixel and 1.5 Gbit/s by modulating four CMOS/micro-LED pixels simultaneously. Apart from the application in VLC, CMOS-controlled micro-LED devices can also be used to implement micro-display systems. A colour-tunable micro-display system capable of delivering high-resolution microscale dynamic images and tuning its colour from red to green has been demonstrated based on new LED epitaxial LED structures, micro-LED fabrication, and the CMOS technology. Other work reported in this thesis includes using micro-LEDs for data transmission in plastic optical fibre and investigating the modulation characteristics of colour-converters such as colloidal quantum dots and light-emitting polymer. A detailed study on size-dependent capacitance in III-nitride micro-LEDs, especially the negative capacitance (NC) effect, has also been reported in this thesis. This capacitance research sheds light on the mechanisms underlying the NC effect and is potentially useful for improving the LED performance for VLC and other applications.

Download or read book Optics in Our Time written by Mohammad D. Al-Amri and published by Springer. This book was released on 2016-12-12 with total page 509 pages. Available in PDF, EPUB and Kindle. Book excerpt: Light and light based technologies have played an important role in transforming our lives via scientific contributions spanned over thousands of years. In this book we present a vast collection of articles on various aspects of light and its applications in the contemporary world at a popular or semi-popular level. These articles are written by the world authorities in their respective fields. This is therefore a rare volume where the world experts have come together to present the developments in this most important field of science in an almost pedagogical manner. This volume covers five aspects related to light. The first presents two articles, one on the history of the nature of light, and the other on the scientific achievements of Ibn-Haitham (Alhazen), who is broadly considered the father of modern optics. These are then followed by an article on ultrafast phenomena and the invisible world. The third part includes papers on specific sources of light, the discoveries of which have revolutionized optical technologies in our lifetime. They discuss the nature and the characteristics of lasers, Solid-state lighting based on the Light Emitting Diode (LED) technology, and finally modern electron optics and its relationship to the Muslim golden age in science. The book’s fourth part discusses various applications of optics and light in today's world, including biophotonics, art, optical communication, nanotechnology, the eye as an optical instrument, remote sensing, and optics in medicine. In turn, the last part focuses on quantum optics, a modern field that grew out of the interaction of light and matter. Topics addressed include atom optics, slow, stored and stationary light, optical tests of the foundation of physics, quantum mechanical properties of light fields carrying orbital angular momentum, quantum communication, and Wave-Particle dualism in action.

Download or read book LED Based Visible Light Communications written by Nan Chi and published by Springer. This book was released on 2018-09-01 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book systematically introduces the visible light communication (VLC) technology in detail. Basic concepts and how to realize the system are both illustrated, including the transmitter, channel, and the receiver. In addition, a good many experimental results are presented to help readers further understand the VLC technologies. The upper-layer protocols of visible light communication system and the technology trends are also discussed. This book can be a good reference work for researchers, engineers, and graduate students in the fields of communications, LED, and optics.

Download or read book III Nitride Based Light Emitting Diodes and Applications written by Tae-Yeon Seong and published by Springer Science & Business Media. This book was released on 2014-07-08 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: Light emitting diodes (LEDs) are already used in traffic signals, signage lighting, and automotive applications. However, its ultimate goal is to replace traditional illumination through LED lamps since LED lighting significantly reduces energy consumption and cuts down on carbon-dioxide emission. Despite dramatic advances in LED technologies (e.g., growth, doping and processing technologies), however, there remain critical issues for further improvements yet to be achieved for the realization of solid-state lighting. This book aims to provide the readers with some contemporary LED issues, which have not been comprehensively discussed in the published books and, on which the performance of LEDs is seriously dependent. For example, most importantly, there must be a breakthrough in the growth of high-quality nitride semiconductor epitaxial layers with a low density of dislocations, in particular, in the growth of Al-rich and and In-rich GaN-based semiconductors. The materials quality is directly dependent on the substrates used, such as sapphire, Si, etc. In addition, efficiency droop, growth on different orientations and polarization are also important. Chip processing and packaging technologies are key issues. This book presents a comprehensive review of contemporary LED issues. Given the interest and importance of future research in nitride semiconducting materials and solid state lighting applications, the contents are very timely. The book is composed of chapters written by leading researchers in III-nitride semiconducting materials and device technology. This book will be of interest to scientists and engineers working on LEDs for lighting applications. Postgraduate researchers working on LEDs will also benefit from the issues this book provides.

Download or read book High speed Gan based Photonic Crystal Light emitting Diodes for Visible Light Communication Applications written by 林東慶 and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Nanomaterials for Light Emitting Diodes and Solar Cells written by Baiquan Liu and published by Frontiers Media SA. This book was released on 2021-09-29 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Antenna Systems written by Hussain Al-Rizzo and published by BoD – Books on Demand. This book was released on 2022-04-28 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers an up-to-date and comprehensive review of modern antenna systems and their applications in the fields of contemporary wireless systems. It constitutes a useful resource of new material, including stochastic versus ray tracing wireless channel modeling for 5G and V2X applications and implantable devices. Chapters discuss modern metalens antennas in microwaves, terahertz, and optical domain. Moreover, the book presents new material on antenna arrays for 5G massive MIMO beamforming. Finally, it discusses new methods, devices, and technologies to enhance the performance of antenna systems.

Download or read book Colloidal Quantum Dot enabling and Alternating Current Driven Gallium Nitride Based Light Emitting Diode Technology written by Jie Liu and published by . This book was released on 2013 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt: