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PhC structure for high contrast XOR/OR/NOT logic

optical AND QUANTUM ELECTRONICS 2024年第5期56卷 1-14页

作者： Shreya, Kalapatapu Shaik, Enaul Haq Balaji, v. R. Dhanabalan, Shanmuga Sundar Sridarshini, T. Hegde, Gopalkrishna Vellore Inst Technol Sch Comp Sci & Engn Chennai CampusVandalur Kelambakkam Rd Chennai 600127 Tamil Nadu India Vasireddy Venkatadri Inst Technol Dept Elect & Commun Engn Guntur 522508 Andhra Pradesh India Vellore Inst Technol Ctr Healthcare Advancement Innovat & Res Vandalur Kelambakkam Rd Chennai 600127 Tamil Nadu India RMIT Univ Funct Mat & Microsyst Res Grp Sch Elect & Comp Engn Melbourne Vic 3001 Australia Anna Univ Coll Engn Dept Elect & Commun Engn Guindy Campus Chennai 600025 India Indian Inst Sci Ctr Nanosci & Engn Bengaluru 560012 India

In this paper, we propose a single photonic crystal structure to implement NOT/XOR/OR optical logic gates using interference phenomenon. The gates are designed as T-shaped waveguides. The filter rods used in the design enhance the contrast ratio by up to 82.25 dB compared with the existing designs reported in the literature so far, and provides a maximum bit rate of 1.567Tbps with a response time of 0.63 ps. The proposed design exhibits minimum power loss, and performance parameters are enhanced compared to existing reported works. Photonic logic gates emerged as a potential substitute for their traditional electronic counterparts due to quick speed, low power consumption, and compatibility with current optical communication networks. The size of the proposed device is 144 mu m2, can be used for future optical computing and communications.

关键词： Interference T-shaped waveguide Logic gates Contrast ratio NOT/XOR/OR

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design of ophthalmic contact lens using Q-type aspheres with reduced error budget for high visual acuity 25

Design of ophthalmic contact lens using Q-type aspheres with...

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Conference on current developments in Lens design and optical engineering XXv

作者： Peng, Wei-Jei Lee, Tsung-Xian Natl Taiwan Univ Sci & Technol Grad Inst Appl Sci & Technol 43Sec 4Keelung Rd Taipei 106 Taiwan Natl Taiwan Univ Sci & Technol Grad Inst Color & Illuminat Technol 43Sec 4Keelung Rd Taipei 106 Taiwan

ISBN: (纸本)9781510679221;9781510679238

This paper investigates the design of an ophthalmic rigid contact lens (CL) that has a Q-type aspheric surface to reduce the tolerance error budget and produce higher visual acuity. CLs for myopia correction are typically made with spherical surfaces;when such CLs are worn in darkness, the visual acuity degrades severely due to the spherical aberration generated by pupil dilation. To maximize visual acuity, an aspheric CL is essential because it can correct the spherical aberration. In this study, a CL is designed based on a schematic eye model for evaluating the modulation transfer function (MTF) on the retina, and the result shows that the visual acuity produced by an aspheric CL is superior to that produced by a spherical CL. The traditional power-series polynomial is commonly used for aspheric surface design, but the aspheric slope cannot be controlled during optimization. The large slope departure from a best-fit sphere leads to high tolerance sensitivity and an inflection point;however, the CL does not permit such results. To solve this problem, the Q-type polynomial with slope constraint proposed by Forbes is applied to the aspheric CL in this study. The Q-type aspheric polynomial can not only enhance the optimization efficiency due to its orthogonal characteristics, but also reduce error budget for maximal manufacturing yield. The simulation results demonstrated that the spherical aberration is successfully reduced by the Q-type aspheric CL for better visual acuity in darkness.

关键词： Rigid contact lens Q-type asphere power-series asphere myopia correction spherical aberration schematic eye model

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optical design process of a human eye inspired lens 23

Optical design process of a human eye inspired lens

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Conference on current developments in Lens design and optical engineering XXIII Part of SPIE Optics and Photonics Conference

作者： Allain, Guillaume Thibault, Simon Univ Laval Fac Sci & Genie Dept Phys Genie Phys & Opt 1045 Ave Med Laval PQ G1V 0A6 Canada COPL 2375 Rue Terrasse Quebec City PQ G1V 0A6 Canada

ISBN: (纸本)9781510654198;9781510654181

Bio-inspired optical design can be described as a conscious decision in the design process to take inspiration from physical adaptation that were brought up by natural selection. The usual goal is to introduce non-conventional techniques or material in order to achieve better performance or novel applications. However, when the target is to imitate closely the form-factor, appearance and optical properties of a biological system, new requirements are added to the design process and new problems arises. In this paper, we will expose the design of an optical system that draws most requirements from both the optical properties and the form-factor of the human eye. However, contrary to human eye models, the main requirements for this project is to make a realistic design which can be assembled as a prototype. The design process will be laid out, by firstly introducing system requirements and various performance targets that comes from the bio-inspired design. The constraints associated with using entrance pupil's appearance as a requirement will be presented. This paper will also specifically be looking at distortion as a solution for modulating resolution throughout the field of view and as a tool to aid in those novel problems.

关键词： optical design Bio-inspired design Human eye optical design methodology optical Distortion

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current status of digital twin architecture and application in nuclear energy field

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ANNALS OF NUCLEAR ENERGY 2024年 202卷

作者： Hu, Mengyan Zhang, Xueyan Peng, Cuiting Zhang, Yixuan Yang, Jun Huazhong Univ Sci & Technol Sch Energy & Power Engn State Key Lab Coal Combust & Low Carbon Utilizat Wuhan 430074 Peoples R China Huazhong Univ Sci & Technol Luoyu Rd 1037 Huazhong Peoples R China

Digital Twin (DT) technology has gained significant attention in various areas, including nuclear energy. Technologies such as machine learning, artificial intelligence, and high-fidelity modeling and simulation have been studied to further the digitalization of the nuclear industry. In this paper, an overview of the DT initiatives and developments for the design optimization and intelligent transformation of nuclear energy systems is described to provide a development trend of DT technology for nuclear reactors. For the design of DT for complex systems such as nuclear reactors, Model Based Systems engineering (MBSE) technology offers requirements models, design processes, and system verification that are clearer, more precise, and more comprehensive. Four properties of Digital Twin for Nuclear Reactor System (DTNRS) are summarized, which are given by the block definition diagram of MBSE philosophy. Then, to bridge the gap between numerical models and theoretical research of DT, a systematic and hierarchical "v " architecture is proposed, which reflects the digital -related technologies of the DTNRS throughout the whole life cycle. Furthermore, a four -layered decomposition construction model is developed and a prospective application scenario of DTNRS is pictured. Finally, the five -step instructive demonstration of the DTNRS is given based on a Generation III (GEN-III) reactor with its visualized condition map.

关键词： Digital twin Digital reactor MBSE Systematic and hierarchical "v " architecture Thermal -hydraulic

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Dioptric Plan Multi Apochromat objectives for microscopes. optical design 14

Dioptric Plan Multi Apochromat objectives for microscopes. O...

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current developments in Lens design and optical engineering XXIv 2023

作者： Frolov, Dmitry N. vinogradova, Olga A. Frolov, Alexey D. Pavlii, Aleksandr D. Project Labor-microscopes St.-Petersburg Russia LLC "Optotekhnika" St.-Petersburg Russia

ISBN: (纸本)9781510665460

For some types of studies on a microscope, optics is required, which has a multi apochromatic aberration correction in a continuous spectral range from the nearest short -wave Uv to the nearest IR spectral areas. In the NUv range, in some cases, it is required to ensure the focus of laser sources radiation on the wavelengths of 248, 222, 213 and even 193 Nm. The work is also required for the near IR region, for example, for focusing laser sources radiation on wavelengths 1315, 1523 and even 2010 and 2080 nm. A priori such optics should also work in a visible spectral range. All studies can be carried out within the indicated a continuous NUv - NIR of the range. We propose to investigate the fundamental possibility of creating lens objectives for which chromatic aberrations are corrected in a wide spectral range. In addition, optics are required for research in the SWIR, MWIR, and LWIR spectral ranges. © 2023 SPIE.

关键词： Microscopes

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Single elemental planar light concentrator using skewed v-groove optics

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RESULTS IN engineering 2024年 24卷

作者： Ramachandran, Animesh M. Asok, Adersh CSIR Natl Inst Interdisciplinary Sci & Technol NII Ctr Sustainable Energy Technol Thiruvananthapuram 695019 Kerala India Acad Sci & Innovat Res AcSIR Ghaziabad 201002 India

Light concentrators are widely used to address the challenges of solar radiation's limited energy density. However, traditional light concentrators suffer from bulkiness, higher focal length, low solar acceptance, and cost factor due to the usage of large imaging optics elements. Waveguide-based planar light concentrators (PLC) have been engineered as a solution to these challenges. They work by collecting light at the incident face and channeling it to the lateral face of the waveguides. However, the existing PLC designs mostly consist of multiple optics elements, resulting in the need for precise positioning and point-to-point solar tracking. Addressing these complexities, a new design for waveguide-based PLC is presented. It features a simplified array of skewed v-grooves within an optical slab, essentially creating a single elemental optics. This novel skewed v-groove-based PLC (Sv-PLC) introduces a low-concentration (i.e., <10X geometric concentration (GC)) solution that offers high angular acceptance along one axis. The current study aims to establish the novel design concept, validate, optimize, and assess the design through the Ray-tracing simulation. Further, based on the simulation results, a functional prototype was successfully fabricated in PMMA using laser machining. The results of the optical characterization of the Sv-PLC showed that the optical Efficiency (OE) was approximately around half the theoretical OE. Angular-dependent ray trace results showed a lower OE drop (<10 %) for incident angles less than 15 degrees, degrees , and a maximum drop of 30 % (for a 10X GC design) for an incident angle of 23.5 degrees degrees (i.e., half the angle shift of the sun through seasons).

关键词： Ray tracing

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Halogen source illumination optimization using a beam shaping biconic lens array 14

Halogen source illumination optimization using a beam shapin...

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current developments in Lens design and optical engineering XXIv 2023

作者： Smeesters, Lien Rosseel, Dries vervaeke, Michael Thienpont, Hugo Department of Applied Physics and Photonics Pleinlaan 2 Brussels1050 Belgium

ISBN: (纸本)9781510665460

Illumination optical design using non-coherent sources is of major interest for sensing applications requiring a uniform illumination. We present the development of a custom biconic lens array, enabling beam shaping of a halogen source array to a rectangular uniform illumination. First, the tungsten halogen sources were accurately modelled considering the near-field emission pattern and broadband spectrum. Following, the illumination lens array is optimized, including a study on the optimal arrangement and pitch of the array, and ensuring a manufacturable design by taking the optical and mechanical tolerances into account. The optimized lens array comprises of custom lenses (Ø 20 mm) featuring a first spherical surface and a second biconic surface with different radii of curvature and aspherical coefficients (up to the 8th order) in the X and Y direction. A spatial uniformity, defined as the standard deviation of the flux distribution, of 0.0002 was achieved within the envisioned illumination area of 50 x 20 mm2 being close to a perfect uniformity considering a targeted value of 0. Finally, the aspheric biconic lens is manufactured using ultraprecision diamond tooling (Nanotech 350FG), and its performance is successfully validated in a laboratory demonstrator setup, giving rise to an optimized and uniform halogen source illumination. © 2023 SPIE.

关键词： optical design

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Realizing low-distortion in miniature wide-angle lens with freeform optics technique 23

Realizing low-distortion in miniature wide-angle lens with f...

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Conference on current developments in Lens design and optical engineering XXIII Part of SPIE Optics and Photonics Conference

作者： Zhuang, Zhenfeng Parent, Jocelyn Roulet, Patrice Thibault, Simon Immervision Inc 2020 Robert Bourassa BlvdSuite 2320 Montreal PQ H2A 2A5 Canada Univ Laval Dept Phys Genie Phys & Opt 2375 Rue Terrasse Laval PQ G1V 0A6 Canada

ISBN: (纸本)9781510654198;9781510654181

Distortion is one major shortcoming of conventional wide-angle lens. The correction of distortion can maximize field of view in a wide-angle lens and benefit natural scenes. In this paper, we propose a compact wide-angle lens utilizing freeform surfaces to address the shortcoming. The design approaches, including the starting point selection, freeform surface conversion scheme, and system optimization, are discussed in detail. Moreover, freeform diagnostic tools are developed aiming to facilitate system optimization and visualize the critical aspects of optical performance. The simulation results are demonstrated and discussed. Analysis results demonstrate that the design strategies proposed in this paper have been shown to be effective in reducing distortion as well as improving optical performance. We envision that the proposed design schemes will have a positive effect on research and application values for wide angle lens system.

关键词： Lens system design optical systems geometric optical design aspherics

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Testing of fiber optic based sensors for advanced reactors in the Texas A&M University TRIGA reactor

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ANNALS OF NUCLEAR ENERGY 2024年 196卷

作者： Gates, J. Tyler Tsvetkov, Pavel v. Texas A&M Univ Nucl Engn Dept College Stn TX 77843 USA

An optical Fiber Based Gamma Thermometer has been developed and tested at the Texas A&M University reactor as well as the Ohio State Research Reactor. This sensor technology provides temperature measurement of a thermal mass undergoing gamma heating, from which the gamma flux along the length of the sensor may be calculated. The gamma flux data from an array of OFBGTs could allow the determination of local power density within a nuclear reactor core in three dimensions. The design of the sensor makes use of optical fiber as a truly distributed temperature sensor with a spatial resolution less than 1 mm and temperature accuracy of +/- 1 degrees C. The testing program showed that the system provided the expected temperature data for each location. Overall, this sensor technology shows promise for current Light Water Reactors as well as advanced nuclear reactors by providing an unparalleled level of precision in reactor power measurement.

关键词： optical fiber Gamma thermometer Advanced reactor Instrumentation Research reactor

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CO_(2) conversion to solar fuels and chemicals:Opening the new paths

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Journal of Energy Chemistry 2024年第4期91卷 680-683页

作者： Gabriele Centi Claudio Ampelli Department of Chemical BiologicalPharmaceutical and Environmental Sciences(ChiBioFarAm)University of MessinaERIC aisbl and CASPE/INSTMV.le F.Stagno d'Alcontres 3198166 MessinaItaly

This future article discusses the new prospects and directions of CO_(2)conversion via the photo-electrocatalytic(PEC)*** second(2nd)generation solar fuels and chemicals(SFs)are generated directly in PEC systems via electrons/protons reactions without forming molecular H_(2)as an intermediate,overcoming the thermodynamics limitations and practical issues encountered for electro-fuels produced by multistep thermocatalytic processes(***_(2)conversion with H_(2)coming from water electrolysis).A distributed and decentralized production of SFs requires very compact,highly integrated,and intensified *** the existing reactors of advanced design(based on artificial leaves or photosynthesis),the integrated photovoltaic plus electrocatalytic(Pv-EC)device is the only system(demonstrated at large scale)to produce SFs with high solar-to-fuel(STF)***,while the literature indicates STF efficiency as the main(and only)measure of process performance,we remark here the need to refer to productivity(in terms of current density)and make tests with reliable flow PEC systems(with electrodes of at least 5–10 cm^(2))to accelerate the scaling-up *** approaches that minimize downstream separation costs is also *** limitations exist in PEC systems,but most can be overcome by proper electrode and cell engineering,thus going beyond the properties of the *** examples of current developments,we present the progress of(i)artificial leaf/tree devices for green H_(2)distributed production and(ii)a PEC device producing the same chemicals at both cathode and anode parts without downstream operations for green solvent distributed *** on these developments,future directions,such as producing fertilizers and food components from the air,are *** aim is to provide new ideas and research directions from a personal perspective.

关键词： Solar fuels Artificial leaf PEC devices Pv-EC devices Cell engineering green H_(2) Chemicals from theair

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