Advances In Optical Technology Research Articles

A REVIEW ON RADIO OVER FIBER SYSTEMS FOR LONG DISTANCE COMMUNICATION

Recently wireless communication became very vital such that without it, it will be impossible to imagine the human life because it is extensively utilized in several civilian and military applications. These applications include transmission of various image types, high-quality video streaming, online meetings as well as novel bandwidth-intensive user applications like YouTube, Facebook, Netflix, etc. Because the radio signals have a limited bandwidth and are susceptible to atmospheric noise and distortion, they cannot provide bandwidth intensive applications and long distance communications. To provide the recipient of the radio signals to long distances, an advanced optical fiber technology known as Radio over Fiber (RoF) can be utilized faithfully. RoF is technology that modulates the light signal by radio signal and transmit it across a fiber optic link to extend the transmission and wireless access. Currently, this technology has become matured technology in terms of coverage, security and reliability. The RoF system has been implemented for the enhanced performance radio system having larger bandwidth for mobile communications. In addition, these systems have various advantages over traditional systems including higher bandwidth, easy Installation and Maintenance, lower attenuation, dynamic resource allocation, immunity against the RF interference and can transfer high frequency signals that support 5G and beyond 5G network technologies. This paper provides a comprehensive review on the currently existing RoF systems for long distance communication.

Fabrication and Ions Irradiation Study of AlN:Gd Thin Films

Thin films of Aluminum Nitride (AlN) doped with Gadolinium (Gd) are deposited on Si (111) substrates, in pure Nitrogen (N) atmosphere using reactive magnetron sputtering technique at room temperature. The as-deposited thin films are irradiated by protons carrying 335 keV energy with a fluence of 1 × 1014 ions cm−2. Rutherford Backscattering Spectroscopy (RBS) is carried out using a 2 MeV He++ beam to understand the stoichiometric and dimensional features of the films. Modifications in the structural, electronic, optical, and electrical properties are investigated prior to and after the irradiation using X-ray diffraction (XRD), Fourier transforms, infrared spectroscopy (FTIR), diffuse reflectance spectroscopy (DRS), and four-probe point method. Stopping power and range of ions in matters (SRIM) is used to study the non-ionizing energy loss (NIEL) and Frenkel defect density/vacancies in AlN, caused by irradiation. Proton irradiation-induced changes in the structure and enhancement in the optical and electrical characteristics of the films make AlN:Gd a good candidate for advanced electronics and optical technology.

Ultrafast Dynamics Measurement by STM Combined with Advanced Optical Technologies

Ultrafast Dynamics Measurement by STM Combined with Advanced Optical Technologies

DOP18 Advanced optical diagnosis technology for assessment of endoscopic and histological remission in Ulcerative Colitis: A systematic review and meta-analysis

Abstract Background Advanced endoscopic technologies led to significant progress in the definition of endoscopic remission of ulcerative colitis (UC), and correlate better with histological changes, compared to standard endoscopy. However, whilst studies have assessed the diagnostic accuracy of endoscope technologies individually, there is current limited data comparing between technologies. As such, we aimed to compare the correlations between endoscopy and histology disease activity scores across endoscope technologies Methods We searched PubMed and Embase in January 2021 for eligible studies reporting the correlation between endoscopy and histology activity scores in UC. Studies were grouped by endoscope technology as standard-definition white light (SD-WLE), high-definition white light (HD-WLE), or electronic virtual chromoendoscopy (VCE), and comparisons made between these groups Results A total of N=27 studies were identified, of which N=12 were included in a meta-analysis of correlations between endoscopic and histological activity scores. Combining these returned a pooled correlation coefficient (rho) for the SD-WLE group of 0.61, which did not differ significantly from HD-WLE (rho: 0.79, p=0.140) or VCE (rho: 0.70, p=0.471) [Fig 1a]. In addition, N=4 studies reported the accuracy of endoscopic activity scores on WLE and VCE to diagnose histological remission. Pooling these found significantly higher accuracy for VCE, compared to WLE (risk ratio: 1.13, 95% CI: 1.07–1.19, p<0.001).[Fig 1b] Conclusion Activity scores assessed using endoscopy are strongly correlated with activity on histology. VCE appears to have better accuracy for the diagnosis of histological remission in UC, compared to WLE.

Topical Review: Studies of Ocular Function and Disease Using Hyperspectral Imaging.

Advances in imaging technology over the last two decades have produced significant innovations in medical imaging. Hyperspectral imaging (HSI) is one of these innovations, enabling powerful new imaging tools for clinical use and greater understanding of tissue optical properties and mechanisms underlying eye disease.Hyperspectral imaging is an important and rapidly growing area in medical imaging, making possible the concurrent collection of spectroscopic and spatial information that is usually obtained from separate optical recordings. In this review, we describe several mainstream techniques used in HSI, along with noteworthy advances in optical technology that enabled modern HSI techniques. Presented also are recent applications of HSI for basic and applied eye research, which include a novel method for assessing dry eye syndrome, clinical slit-lamp examination of corneal injury, measurement of blood oxygen saturation in retinal disease, molecular changes in macular degeneration, and detection of early stages of Alzheimer disease. The review also highlights work resulting from integration of HSI with other imaging tools such as optical coherence tomography and autofluorescence microscopy and discusses the adaptation of HSI for clinical work where eye motion is present. Here, we present the background and main findings from each of these reports along with specific references for additional details.

Does spatial region of interest (ROI) matter in multispectral and hyperspectral imaging of segmented wheat kernels?

Advances in optics technology and computational processing have brought multispectral and hyperspectral imaging to commercial sorting of fruits and vegetables, yet the application of imaging to single cereal seeds has lagged due to the enormity in numbers of seeds and challenges posed by lighting, shadowing, and seed curvature that are less problematic with larger objects. This study examined the effect of region of interest (ROI) size on the seed surface with respect to the ability to sort seed into accept and reject categories. Regions of interest (ROI) size ranged from 5 centrally located pixels arranged in a cross to all pixels (typically 100) contained in the viewed surface of a kernel. Two modeling structures were used; the first involving all 87 samples, with approximately 220 kernels per sample, in which mixture level of sound and fusarium-damaged kernels is known, but individual kernel class is unknown; and the second involving 5 samples, of which an equal number of 287 known sound and known fusarium-damaged kernels were used. Accordingly, the larger set model characterised the dispersion (by standard deviation) of kernel-to-kernel reflectance at a single representative wavelength, while the smaller set was used to develop linear discriminant analysis classification models using one to three wavelengths. With either case, it was found that the smaller ROIs should be sufficient for a two-class (accepts, rejects) structure. • Hyperspectral imaging of cereal seeds for sorting is gaining popularity. • Seed curvature poses challenges to reflection measurements. • For accept/reject sorting, region of interest may be smaller than the viewed seed.

A novel differential display material: K3LuSi2O7: Tb3+/Bi3+ phosphor with thermal response, time resolution and luminescence color for optical anti-counterfeiting

Optical anti-counterfeiting and encryption have become a hotspot in information security. However, the advanced optical anti-counterfeiting technology still suffers from low security by single-luminescent mode. Herein, we present a novel multi-mode anti-counterfeiting strategy based on K3LuSi2O7: Tb3+/Bi3+ (KLSO: Tb3+/Bi3+) phosphors for the first time. KLSO not only provides various lattice sites for Bi3+ ions occupying to achieve tunable luminescence but can also be non-equivalently substituted by Tb3+ ions to produce persistent or thermo-luminescence. Furthermore, in the pattern “8888” constructed by the mixture of polyacrylic acid (PAA) with KLSO: Tb3+/Bi3+ phosphors, we selectively trigger the three luminescent modes of Bi3+ and Tb3+ ions to realize the design of differential display in the fields of thermal response, time resolution, and luminescence color for optical anti-counterfeiting. The differentiated display can only be presented under specific multi-stimuli response, which further improves the security of information. Our work provides a new insight for designing advanced materials and can be expected to inspire future studies to explore optical anti-counterfeiting technology.

The main directions of scientific research in the field of introducing promising optical technologies in the infrastructure of transport systems.

Projects for the development of the transport system of the Russian Federation involve the introduction of advanced optical technologies in the infrastructure of high-speed modern transport systems in the context of the implementation of un- manned maintenance technologies. The article presents the following areas of research carried out by the authors: — organization of high-speed super-long single-span trunk communication lines without intermediate allocation of digital channels and paths laid in areas with limited access by the maintenance personnel in areas with no infrastructure (underwater obstacles, mountainous terrain, desert and swampy areas). The authors of the article highlighted the main factors influencing the design features of high-speed ultra-long single-span communication lines; — application of photonic switching (PS) technology in high-speed backbone communication networks to ensure operational logical reconfiguration of channel structures and digital paths. Within the framework of this direction of research, the authors have proposed methods for calculating the probabilities of the occurrence of internal blockages in various structures of PS based on the use of the method of mathematical induction in order to synthesize PS structures of a given capacity; — development of effective technologies for remote monitoring of the health of transport infrastructure facilities using passive optical transmission lines. Within the framework of this line of research, the authors analyze the features of the physical prop- erties of optical fibers used as a distributed sensor on the basis of which an integrated system can be built that can measure various physical parameters, such as vibration, deformation, temperature and other parameters.

Fluorescent reflector and image-processing-based D2D beam-steering system for V2V applications

Device-to-device (D2D) communication that delivers a dedicated channel with low latency and high spectral efficiency has been considered an essential solution for vehicle-to-vehicle (V2V) communication. To achieve such D2D-V2V communication, the beam-steering technique using optical wavelengths can be an attractive candidate due to the advanced optical wireless technologies for point-to-point applications. Recently, there has been research on high-performance optical beam-steering techniques based on microelectromechanical systems mirrors and spatial light modulators in quasi-static indoor environments. Due to the optomechanical complexity, size, and cost, however, their suitability for D2D-V2V applications is problematic. In this work, a cost-effective optical beam-steering system based on a fluorescent reflector and stereo vision for D2D-V2V is introduced. Proof-of-concept demonstration using off-the-shelf devices and components shows that the proposed system can support +-30-deg field of view with a data rate of 300 Mb/s.

Clinical utility of Abbott Alinity hq extended red blood cell parameters in differentiating β-thalassemia trait and iron deficiency anemia.

The objective of the study was to evaluate the performance of the Abbott Alinity hq advanced multi angle polarized scatter separation (MAPSSTM )-based optical RBC technology, for the differentiation between iron deficiency anemia (IDA) and β-thalassemia carrier status. Four hundred and sixty-four samples were analyzed. 228 were healthy controls, 30 were β-thalassemia carriers, and 40 were IDA. Receiver operating characteristics analysis evaluated the performance of red cell parameters and mathematical formulas. RBC concentration was the most efficient discriminant (area under the curve; AUC of 0.963, Youden Index of 0.88) followed by red blood cell distribution width in size distribution (AUC of 0.960 and YI of 0.86), and red blood cell distribution width coefficient of variation (AUC of 0.924, and YI of 0.74). The absolute reticulocyte concentration showed good diagnostic efficiency, with AUC of 0.808. Hemoglobin distribution width, the %CV of directly measured cellular hemoglobin concentration, and CHCr, the average hemoglobin concentration of reticulocytes have emerged as novel discriminating parameters, with AUC of 0.749 and 0.785, respectively. The England and Fraser index was the best discriminating mathematical formula based on Youden Index of 0.91. The Ricerca, red blood cell distribution width index, Green and King, and Mentzner Index formulas also showed strong discriminative power. The Shine and Lal index, together with the recent mathematical formula M/H, (ratio of percent microcytic and hypochromic red blood cells) demonstrated moderate performance with AUC of 0.796 and 0.740, respectively. Extended red cell analysis delivered by the advanced optical technology on the Alinity hq hematology analyzer has efficient diagnostic utility in the initial discrimination of the two most common microcytic anemias: IDA and β-thalassemia trait.

Medical needs related to the endoscopic technology and colonoscopy for colorectal cancer diagnosis

BackgroundThe high incidence and mortality rate of colorectal cancer require new technologies to improve its early diagnosis. This study aims at extracting the medical needs related to the endoscopic technology and the colonoscopy procedure currently used for colorectal cancer diagnosis, essential for designing these demanded technologies.MethodsSemi-structured interviews and an online survey were used.ResultsSix endoscopists were interviewed and 103 were surveyed, obtaining the demanded needs that can be divided into: a) clinical needs, for better polyp detection and classification (especially flat polyps), location, size, margins and penetration depth; b) computer-aided diagnosis (CAD) system needs, for additional visual information supporting polyp characterization and diagnosis; and c) operational/physical needs, related to limitations of image quality, colon lighting, flexibility of the endoscope tip, and even poor bowel preparation.ConclusionsThis study shows some undertaken initiatives to meet the detected medical needs and challenges to be solved. The great potential of advanced optical technologies suggests their use for a better polyp detection and classification since they provide additional functional and structural information than the currently used image enhancement technologies. The inspection of remaining tissue of diminutive polyps (< 5 mm) should be addressed to reduce recurrence rates. Few progresses have been made in estimating the infiltration depth. Detection and classification methods should be combined into one CAD system, providing visual aids over polyps for detection and displaying a Kudo-based diagnosis suggestion to assist the endoscopist on real-time decision making. Estimated size and location of polyps should also be provided. Endoscopes with 360° vision are still a challenge not met by the mechanical and optical systems developed to improve the colon inspection. Patients and healthcare providers should be trained to improve the patient’s bowel preparation.

System design and demonstration of performance monitoring of a butterfly‐shaped arch footbridge

This paper presents an overview of the structural performance monitoring system for a butterfly-shaped arch footbridge located at The Hong Kong Polytechnic University. The system is the product of a multidisciplinary academic collaboration of the pooling expertise of four academic departments, namely, structural engineering, traffic engineering, surveying, and optical communication engineering. This system consists of 88 sensors of 13 types, including an advanced Brillouin optical time-domain analysis technology, an optical fiber Bragg grating technology, a global navigation satellite system (GNSS), and high-performance video cameras. The paper summarizes the modular design, subsystem framework, and advanced features of the monitoring system. Preliminary monitoring results, such as high spatial resolution distributed temperature/strain measurement, global heat-transfer analysis, pedestrian traffic analysis, dynamic characteristics, and GNSS measurements, are introduced. A fire accident is employed to demonstrate the function and value of the monitoring system and provided a rare opportunity to detect damages in a real structure. The monitoring system not only monitors the performance of the bridge in real-time but also provides a multifunctional platform, including an Internet-based software for research and teaching and a touchscreen visualization platform for public education.

Novel Co‐Doped Y2GeO5:Pr3+,Tb3+: Deep Trap Level Formation and Analog Binary Optical Storage with Submicron Information Points

AbstractOptical information storage (OIS) is considered as one of the most promising data storage methods due to unique advantages of high security, long life, and low‐energy consumption. Combination of optically stimulated luminescence of electron‐trapping materials (ETMs) and advanced optical technology has been proved to be a feasible approach to break through physical limitations of traditional storage technology. However, inorganic ETMs are limited to laboratory research, and have not realized the submicron recording point of “microscopic” analog optical storage so far. In this work, an exemplary application of OIS employing inorganic ETMs by a custom‐built optical system has been realized for the first time. Multidimensional triple traps are tailored through co‐doping of selective rare‐earth ions Tb3+ into Pr3+‐activated Y2GeO5. Furthermore, first principles calculations, combined with X‐ray photoelectron spectroscopy and low‐temperature electron spin resonance spectra, reveal the nature of trap levels. Remarkably, a {10 × 10} array of information points is automatically recorded in a bit‐by‐bit mode by a 515 nm femtosecond laser, then decoded by linear continuous scanning, and the emission spectrum between each two information points is detected to realize “0” and “1” in binary information. Hopefully, the present work can push forward practical application of inorganic ETMs in high‐density and super‐speed OIS.

Gaussian Pulse Propagation via Bright and Dark Solitons through an Atomic Medium

We study the Gaussian pulse propagation and its absorption, dispersion, and distortion in an atomic medium for advanced optical technology. The output pulse intensity distribution in time and Rabi oscillations, as well as the phase of control fields, show significant dark and bright forms of soliton shapes. We investigate the localized intensity of dark and bright solitons with the intensity of control fields in time domain within the normal and anomalous group velocity dispersion regions. Uniform undistorted pulse intensity and bright soliton are noted in time domain with the phase variation of control fields. These theoretical results are useful for optical fibers due to their minimum losses of the signal quality.

Label-free methods for optical in vitro characterization of protein-protein interactions.

Protein–protein interactions are involved in the regulation and function of the majority of cellular processes. As a result, much effort has been aimed at the development of methodologies capable of quantifying protein–protein interactions, with label-free methods being of particular interest due to the associated simplified workflows and minimisation of label-induced perturbations. Here, we review recent advances in optical technologies providing label-free in vitro measurements of affinities and kinetics. We provide an overview and comparison of existing techniques and their principles, discussing advantages, limitations, and recent applications.

Recent Progress of Advanced Optical Manufacturing Technology

Recent Progress of Advanced Optical Manufacturing Technology

3D printing enabled by light and enabling the manipulation of light: feature issue introduction

This feature issue aims at highlighting the two-way connection between optics and photonics and 3D printing. One direction concerns novel photoresist materials and technical advances in optics-based 3D additive manufacturing. The other direction uses such advanced optical 3D printing technologies for the realization of novel micro-optical components, micro-optical systems, 3D artificial materials called metamaterials, micro-robots, and more. All of these would be difficult if not impossible to manufacture otherwise.

3D printing enabled by light and enabling the manipulation of light: feature issue introduction

This feature issue aims at highlighting the two-way connection between optics and photonics and 3D printing. One direction concerns novel photoresist materials and technical advances in optics-based 3D additive manufacturing. The other direction uses such advanced optical 3D printing technologies for the realization of novel micro-optical components, micro-optical systems, 3D artificial materials called metamaterials, micro-robots, and more. All of these would be difficult if not impossible to manufacture otherwise.

Skin tags imaged by reflectance confocal microscopy, optical coherence tomography and multispectral optoacoustic tomography at the bedside

Skin tags are common and mostly benign, but occasionally contain skin cancers. This study analysed skin tags by combining three advanced optical imaging technologies: reflectance confocal microscopy (RCM), optical coherence tomography (OCT) and multispectral optoacoustic imaging (MSOT) supplemented by dermoscopy MATERIALS AND METHODS: A prospective clinical study recruiting patients with skin tags from a university hospital clinic over a 2-week period. OCT, RCM and MSOT imaging were performed prior to excisional biopsies. Image features such as pigmentation, cell types and skin architecture, angiographic information demonstrating vascular pattern were captured, analysed, and compared to melanin and haemoglobin content in MSOT as well as histopathology. Six patients with dermal naevi (2); compound naevi (3); neurofibroma (1) were included. All skin tags except the neurofibroma were pigmented (5/6), with sparse (5/6) and dense (4/6) hyperreflective nests and band-like collagen in dermis in 6/6 lesions on RCM. Dermoscopy showed dots (5/6) and coiled vessels (5/6). Linear vertical vessels were present in all OCT images. MSOT images consisted of a compact shell-like superficial melanin area, same shape and size as the skin tag, dermal vessels were visible in 4/5 naevi, HbO2 signal clearly demarcated blood vessels located below the melanin signal. OCT showed linear vessels in all lesions. Pigmentation was identified by RCM as benign nests of melanocytes. MSOT supplemented with spatial distribution of melanin and HbO2 that indicated all skin tags were benign with no infiltration of vessels inside the melanin signal. Each advanced method proved indispensable for fast diagnosis. Larger studies are warranted for validation.

Imaging dendritic spines: molecular organization and signaling for plasticity.

The structural plasticity of dendritic spines is considered to be essential for various forms of synaptic plasticity and, ultimately, learning and memory. The process is mediated by signaling pathways that promote the reorganization of the actin cytoskeleton and subsynaptic structures, which in turn cause structural and functional changes in dendritic spines. Recent advances in optical technologies have started to reveal the fine molecular structures and dynamic signaling occurring inside spines, providing significant insights into the molecular regulation of spines. Here, we highlight recent studies to resolve the molecular mechanisms underlying the spine actin cytoskeleton and plasticity with high spatiotemporal resolution. Moreover, we discuss new genome editing-based approaches in imaging the molecular structure and plasticity of dendritic spines.