Development Of Optical Technology Research Articles

Recent Patents for Optical Alignment

Background: The installation of optical devices is a necessary operation before their use. Therefore, the configuration of the optical system affects the performance of the whole optical system. However, in the process of optical system installation, there are still some technical breakthroughs to be made in order to better carry out optical system installation in the future. Objective: Through the introduction and discussion of the devices, methods and patent features of optical alignment testing in recent years, some valuable conclusions are summarized, and future research and development are prospected. Methods: The patents of optical system assembly were studied, and the patents and research progress of optical alignment were summarized. Results: With the development of optical technology, optical alignment has become more and more important, so optical alignment is needed to realize the design of optical systems. Conclusion: It is concluded that there is still a large space for the development of optical alignment, and the main development trend is towards high precision and large caliber

Optical properties of crystalline materials based on AgCl0.25Br0.75 – TlCl0.74Br0.26 and AgCl0.25Br0.75 – TlBr0.46I0.54 systems

For the development of optical technologies aimed at research, diagnostics and operation in a wide spectral range, the creation of new materials capable of being highly transparent and effective for transmitting electromagnetic waves in the visible, IR and THz regions is required. This article studies the properties of single crystals and two-phase ceramics based on solid solutions of the AgCl0.25Br0.75 – TlCl0.74Br0.26 and AgCl0.25Br0.75 – TlBr0.46I0.54 systems. The materials showed transparency in the range of 0.4–60.0 and 350–1500 μm (0.20–0.86 THz). With an increase in the proportion of thallium halides in the AgCl0.25Br0.75 solid solutions, a shift and the transmission spectrum broadening to longer wavelengths was observed. These effects are typical for compounds with both Fm3m and Pm3 m type cubic crystal lattice. The refractive indices of the developed materials have normal wavelength dispersion and vary from 2.107 to 2.539 depending on the system and composition. The indicators for solid solutions with an intermediate composition of homogeneity regions lie within the values characteristic of boundary compositions. Based on this data a description of the index dependence by the Sellmeier equation, adapted by Fleming, was obtained. The refractive indices imaginary parts of all developed materials were 0.11*10−4–3.55*10−4, which was 2–4 times lower in comparison with other substances based on silver and thallium halides. The materials were characterized by a photostability improvement with an increase in the part of thallium halides in the solid solution, as well as with a growth in the amount of the orthorhombic phase in the case of two-phase ceramics. The materials showed low values of optical losses, as well as high functional properties. This makes single crystals and ceramics promising for transmission and fiber optics designed to operate in a wide spectral range.

Advances in the Regulation of Neural Function by Infrared Light.

In recent years, with the rapid development of optical technology, infrared light has been increasingly used in biomedical fields. Research has shown that infrared light could play roles in light stimulation and biological regulation. Infrared light has been used to regulate neural function due to its high spatial resolution, safety and neural sensitivity and has been considered a useful method to replace traditional neural regulation approaches. Infrared neuromodulation methods have been used for neural activation, central nervous system disorder treatment and cognitive enhancement. Research on the regulation of neural function by infrared light stimulation began only recently, and the underlying mechanism remains unclear. This article reviews the characteristics of infrared light, the advantages and disadvantages of infrared neuromodulation, its effects on improving individual health, and its mechanism. This article aims to provide a reference for future research on the use of infrared neural regulation to treat neuropsychological disorders.

Face in the mirror, what do you see? Catoptric autoexperimentation and the physiognomic gaze

AbstractTo critically explicate the visual epistemology for catoptric autoexperimentation in the contemporary science of facial behavior, by way of its historical progenitors, I draw upon the pragmatic semiotics of the catoptric phenomenon. This problematization of catoptrics is fundamentally about two different but related concepts: the semiotic threshold and the iconicity debate. Based on primary sources both Western and Eastern, I trace a transcultural history of scientific ideas about performing catoptric auto-experimentation through privileged case studies from physiognomic literary corpora. I probe the ways in which self-recognition has long been pragmatically necessitated as well as processually normative in the study of the face, the research and development of optical technologies has in turn led to paradigm shifts in physiognomic thought, and the procatoptric staging behind the catoptric prosthesis conditions its visual epistemology. I propose that the catoptric prosthesis is not pre- but post-semiotic. That is, the mirror only becomes a mirror when part of a semiotic process and sign relation. The extreme of iconicity that is perceptually afforded by the catoptric prosthesis, far from disqualifying it from the status of a sign, is exactly what distinguishes its role and importance for this semiosis of the face.

Singular optics empowered by engineered optical materials

Abstract The rapid development of optical technologies, such as optical manipulation, data processing, sensing, microscopy, and communications, necessitates new degrees of freedom to sculpt optical beams in space and time beyond conventionally used spatially homogenous amplitude, phase, and polarization. Structuring light in space and time has been indeed shown to open new opportunities for both applied and fundamental science of light. Rapid progress in nanophotonics has opened up new ways of “engineering” ultra-compact, versatile optical nanostructures, such as optical two-dimensional metasurfaces or three-dimensional metamaterials that facilitate new ways of optical beam shaping and manipulation. Here, we review recent progress in the field of structured light–matter interactions with a focus on all-dielectric nanostructures. First, we introduce the concept of singular optics and then discuss several other families of spatially and temporally structured light beams. Next, we summarize recent progress in the design and optimization of photonic platforms, and then we outline some new phenomena enabled by the synergy of structured light and structured materials. Finally, we outline promising directions for applications of structured light beams and their interactions with engineered nanostructures.

A quantum model of charge capture and release onto/from deep traps.

The rapid development of optical technologies and applications revealed the critical role of point defects affecting device performance. One of the powerful tools to study the influence of defects on charge capture and recombination processes is thermoluminescence. The popular models behind thermoluminescence and carrier capture processes are semi-classic though. They offer a good qualitative description, but implicitly exclude the quantum nature of the accompanying parameters, such as frequency factors and capture cross sections. As a consequence, results obtained for a specific host material cannot be successfully extrapolated to other materials. Thus, the main purpose of our work is to introduce a reliable analytical model that describes non-radiative capture and release of electrons from/to the conduction band (CB). The proposed model is governed by Bose-Einstein statistics (for phonon occupation) and Fermi's golden rule (for resonant charge transfer between the trap and the CB). The constructed model offers a physical interpretation of the capture coefficients and frequency factors, and seamlessly includes the Coulomb neutral/attractive nature of traps. It connects the frequency factor to the overlap of wavefunctions of the delocalized CB and trap states, and suggests a strong dependence on the density of charge distribution, i.e. the ionicity/covalency of the chemical bonds within the host. Separation of the resonance conditions from the accumulation/dissipation of phonons on the site leads to the conclusion that the capture cross-section does not necessarily depend on the trap depth. The model is verified by comparison to the reported experimental data, showing good agreement. As such, the model generates reliable information about trap states whose exact nature is not completely understood and allows performing materials research in a more systematic way.

Enhanced property of flexible UV photodetectors based on electrospinning ZnO–SnO2 heterojunction nanofibers by the formation of Zn2SnO4

Developing new photodetectors with good photoresponse, high stability, flexibility, and minimalization is urgently demanded facing the rapid development of optical technology. In this work, ZnO–SnO2 heterojunction nanofibers are synthesized by electrospinning. The flexible UV micro-photodetector is fabricated by combining ZnO–SnO2 heterojunction nanofibers with photolithography-patterned Au microelectrodes on PI substrate. An extremely low dark current (∼10−11 A) is obtained due to the formation of Zn2SnO4 layer at the large interface of ZnO–SnO2 heterojunctions. Upon exposure to UV light with power density of 24 μW cm−2, the photodetector exhibits high on–off ratio of ∼104, high responsibility of 267 A W−1, and fast response speed of 2.75 s. The photodetector has good photoelectric properties and high UV selectivity. Moreover, the flexibility of the UV photodetector is demonstrated. The photoresponse remains ∼60% of the initial level even under a large bending angle of 45°. The combined utilization of electrospinning and photolithography is convenient to fabricate flexible UV photodetectors.

Diesel Spray: Development of Spray in Diesel Engine

Research and development in the internal combustion engine (ICE) has been growing progressively. Issues such as air pollution, fuel cost, and market competitiveness have driven the automotive industry to develop and manufacture automobiles that meet new regulation and customers’ needs. The diesel engine has some advantages over the gasoline or spark ignition engine, including higher engine efficiency, greater power output, as well as reliability. Since the early stage of the diesel engine’s development phase, the quest to obtain better atomization, proper fuel supply, and accurate timing control, have triggered numerous innovations. In the last two decades, owing to the development of optical technology, the visualization of spray atomization has been made possible using visual diagnostics techniques. This advancement has greatly improved research in spray evolution. Yet, a more comprehensive understanding related to these aspects has not yet been agreed upon. Diesel spray, in particular, is considered a complicated phenomenon to observe because of its high-speed, high pressure, as well as its high temperature working condition. Nevertheless, several mechanisms have been successfully explained using fundamental studies, providing several suggestions in the area, such as liquid atomization and two-phase spray flow. There are still many aspects that have not yet been agreed upon. This paper comprehensively reviews the current status of theoretical diesel spray and modelling, including some important numerical and experimental aspects.

Optical techniques in non-destructive detection of wheat quality: A review

Wheat quality detection is essential to ensure the safety of wheat circulation and storage. The traditional wheat quality detection methods mainly include artificial sensory evaluation and physicochemical index analysis, which are difficult to meet the requirements for high accuracy and efficiency in modern wheat quality detection due to the disadvantages of subjectivity, destruction of sample integrity and low efficiency. With the rapid development of optical technology, various optical-based methods, using near-infrared spectroscopy technology, hyperspectral imaging technology and terahertz, etc., have been proposed for wheat quality detection. These methods have the characteristics of non-destructiveness and high efficiency which make them popular in wheat quality detection in recent years. In this paper, various state-of-the-art optical-based techniques of wheat quality detection are analyzed and summarized in detail. Firstly, the principle and process of common optical non-destructive detection methods for wheat quality are introduced. Then, the optical techniques used in these detection methods are divided into seven categories, and the comparison of these technologies and their advantages and disadvantages are further discussed. It shows that terahertz technology is regarded as the most promising wheat quality detection method compared with other optical detection technologies, because it can not only detect most types of wheat deterioration, but also has higher accuracy and efficiency. Finally, the research of optical technology in wheat quality detection is prospected. The future research of optical technology-based wheat quality detection mainly includes the construction of wheat quality optical detection standardization database, the fusion of multiple optical detection technologies and multiple quality index information, the improvement of the anti-interference of optical technology and the industrialization of optical inspection technology for wheat quality. These studies are of great significance to improve the detection technology of wheat and ensure the storage safety of wheat in the future.

Determination of the Diffusion Coefficient of 40%-Glucose in Human Gum Tissue by Optical Method

The problem of increasing the depth of light penetration in biotissues, which is solved by the use of immersion agents, including hyperosmotic ones, such as glucose, is urgent because of the significant development of optical technologies and methods used for non-invasive diagnostics of biotissues, as well as for clarifying the protocols of photodynamic therapy, photothermal destruction, optical biopsy, tomography, etc. In this case, it is important to determine the quantitative characteristics of the diffusion of immersion agents in biological tissues. In this work, the effective diffusion coefficient of 40% glucose solution in the human gum mucosa tissue has been determined in vitro, which was (4.1 ± 0.8) × 10–6 cm2/s. The method is based on the recording of the kinetics of changes in the diffuse reflectance spectra and the application of a free diffusion model.

Analysis of Coordinates Decoupling of Multi-Dimensional Precision Optical Adjusting Frame in Optical Alignment

Information technology has much promoted the development of optical technology. With the help of computer technology, people can design and manufacture more complex optical systems than before, to obtain ideal imaging quality. The complexity of the optical system brings enormous challenges to optical alignment. Optical system alignment is the crucial link of transforming the excellent optical design into instruments with good performance in reality. Precision alignment of an optical system requires precise adjustment of each component's degree of freedom using a specific adjusting mechanism. Due to the quantification and compensation correction for the coordinates coupling relationship among each dimension adjusting freedom of the adjusting frame can not be carried out. Generally, the coordinates coupling problem is usually ignored in optical system alignment, to cause the optical adjustment error. This paper carries out an analysis for the coupling relationship among each dimension motion freedom of multi-dimensional precision optical adjusting frame in details by mathematical modeling and simulation, the decomposed transformation for each dimension adjusting mount of multi-dimensional precision optical adjusting frame, and the compensation correction for the coordinates coupling among each dimension adjusting mount. The test results show that this method can effectively reduce the difference between the actual mechanical adjusting mount and the expected optical adjusting mount, to achieve more accurate optical adjustment.

Optical gas detection: key technologies and applications review

Rapid identification and detection of gases is a major problem that needs to be solved urgently by researches from worldwide. With the development of optical technology, optical gas detection technology has attracted great attention due to its remarkable advantages of high efficiency, multi-component detection ability and high sensitivity. In this paper, the theoretical foundation of optical gas detection technology is first introduced. Then the working principles and applications of various optical detection technologies for typical gases according to active and passive detection are reviewed. Using these gas detection technologies, dozens of gases have been continuously monitored at long distance with high sensitivity. The measurements of gas composition, concentration, temperature and other parameters in a variety of scenarios are realized, which effectively reduces the occurrence of dangerous accidents. By summarizing and analyzing the technical problems that still exist in the current optical gas detection technology, the future development trend is prospected.

Ultrahigh-Resolution Optical Vector Analyzers

The optical vector analyzer is a device used to measure the magnitude, phase responses, and other parameters of optical devices. There have been increasingly higher demands placed on optical vector analyzers during the development of optical technologies, which are satisfied by the creation of new devices and their operating principles. For further development in this area, it is necessary to generalize the experience gained during the development of optical vector analyzers. Thus, in this report, we provide an overview of all the basic types of approaches used for the realization of optical vector analyzers, including the advanced ones with the best performances. The principles of their working, as well as their associated advantages, disadvantages, and existing solutions to the identified problems, are examined in detail. The presented approaches could be of value and interest to those working in the field of laser dynamics and optical devices, as we propose one use of the optical vector analyzer as being the characterization of Fano resonance structures.

Diagnostic prospects and preclinical development of optical technologies using gold nanostructure contrast agents to boost endogenous tissue contrast.

Numerous developments in optical biomedical imaging research utilizing gold nanostructures as contrast agents have advanced beyond basic research towards demonstrating potential as diagnostic tools; some of which are translating into clinical applications. Recent advances in optics, lasers and detection instrumentation along with the extensive, yet developing, knowledge-base in tailoring the optical properties of gold nanostructures has significantly improved the prospect of near-infrared (NIR) optical detection technologies. Of particular interest are optical coherence tomography (OCT), photoacoustic imaging (PAI), multispectral optoacoustic tomography (MSOT), Raman spectroscopy (RS) and surface enhanced spatially offset Raman spectroscopy (SESORS), due to their respective advancements. Here we discuss recent technological developments, as well as provide a prediction of their potential to impact on clinical diagnostics. A brief summary of each techniques' capability to distinguish abnormal (disease sites) from normal tissues, using endogenous signals alone is presented. We then elaborate on the use of exogenous gold nanostructures as contrast agents providing enhanced performance in the above-mentioned techniques. Finally, we consider the potential of these approaches to further catalyse advances in pre-clinical and clinical optical diagnostic technologies.

Определение коэффициента диффузии 40%-глюкозы в ткани десны человека оптическим методом

Due to the significant development of optical technologies and methods used for both noninvasive diagnostics (optical biopsy, tomography, etc.) and improvement of therapeutic protocols (photodynamic therapy, photothermal destruction, etc.), the increasing of the penetration depth of light into tissues is an urgent problem, which is solved using immersion agents, including hyperosmotic, such as glucose. Moreover, the determination of the quantitative characteristics of the diffusion of immersion agents in tissues is important. In this work, we determined the effective diffusion coefficient of a 40%-glucose solution in human gingival mucosa tissue in vitro, which was (4.1 ± 0.8) • 10-6 cm2/s. The method is based on recording the kinetics of changes in the diffuse reflection spectra and applying the free diffusion model.

Surface profilometry of silicon wafers using wavelength-tuned phase-shifting interferometry

Surface profile is one of the key evaluation indexes in the optical industry. With the development of optical technology, wavelength-tuned phase-shifting interferometry has been widely used for measuring the surface profiles of optical components based on the high accuracy of this technique. However, coupling errors caused by higher harmonics and phase-shift errors may lead to systematic errors in the calculated phase. In this research, to suppress coupling errors effectively, we propose an 8N - 7 phase-shifting algorithm consisting of a novel polynomial window function and discrete Fourier transform. By locating eight multiple roots on the characteristic diagram, the polynomial window function of the proposed algorithm is derived based on the theory of characteristic polynomials. The characteristic polynomial of the 8N - 7 algorithm is estimated based on a Fourier representation. Phase errors are discussed and compared to the errors in other algorithms. The results indicate that the 8N - 7 algorithm has the smallest phase error among the compared algorithms and can compensate for up to sixth-order nonlinearity in phase measurements. Finally, the proposed algorithm was applied to profile the surface of a silicon wafer. The results revealed that the standard deviation across 20 experiments was 3.231 nm, which is much smaller than the standard deviations of conventional phase-shifting algorithms.

Subcycle Transient Scanning Tunneling Spectroscopy with Visualization of Enhanced Terahertz Near Field

The recent development of optical technology has enabled the practical use of a carrier-envelope phase-controlled monocycle electric field in the terahertz (THz) regime. By combining this technique...

A Guide to Emerging Technologies for Large-Scale and Whole-Brain Optical Imaging of Neuronal Activity.

The mammalian brain is a densely interconnected network that consists of millions to billions of neurons. Decoding how information is represented and processed by this neural circuitry requires the ability to capture and manipulate the dynamics of large populations at high speed and high resolution over a large area of the brain. Although the use of optical approaches by the neuroscience community has rapidly increased over the past two decades, most microscopy approaches are unable to record the activity of all neurons comprising a functional network across the mammalian brain at relevant temporal and spatial resolutions. In this review, we survey the recent development in optical technologies for Ca2+ imaging in this regard and provide an overview of the strengths and limitations of each modality and its potential for scalability. We provide guidance from the perspective of a biological user driven by the typical biological applications and sample conditions. We also discuss the potential for future advances and synergies that could be obtained through hybrid approaches or other modalities.

Application of fluorescence in the identification of circulating tumor cells

There are many ways to identify circulating tumor cells in the current. Fluorescence has a wide range of applications in the identification of circulating tumor cells. The labeled cells can be observed and counted more intuitively by labeling the tumor cells with fluorescent group containing antibodies, probes and aptamers, and cytokine, CD45 and fluorescence in situ hybridization are widely used in the identification of various circulating tumor cell related tests. In recent years, people have explored the feasibility of using fluorescent probes to directly identify circulating tumor cells. With the development of biopsy probes and optical sectioning imaging technology of confocal microscopy, it is possible to directly identify circulating tumor cells with fluorescent probes in the future. Key words: Neoplasm circulating cells; Fluorescence; In situ hybridization, fluorescence; Probe

Multi-objective evolutionary optimization for geostationary orbit satellite mission planning

In the past few decades, applications of geostationary orbit (GEO) satellites have attracted increasing attention, and with the development of optical technologies, GEO optical satellites have become popular worldwide. This paper proposes a general working pattern for a GEO optical satellite, as well as a target observation mission planning model. After analyzing the requirements of users and satellite control agencies, two objectives are simultaneously considered: maximization of total profit and minimization of satellite attitude maneuver angle. An NSGA-II based multi-objective optimization algorithm is proposed, which contains some heuristic principles in the initialization phase and mutation operator, and is embedded with a traveling salesman problem (TSP) optimization. The validity and performance of the proposed method are verified by extensive numerical simulations that include several types of point target distributions.