Iet Optoelectronics最新文献

{"title":"Semitransparent Perovskite Solar Cells: Concept, Materials, Architectures and Challenges for Next-Generation Photovoltaics","authors":"Amina Shafique,&nbsp;Uzma Amin,&nbsp;Ahmed Abu-Siada","doi":"10.1049/ote2.70045","DOIUrl":"https://doi.org/10.1049/ote2.70045","url":null,"abstract":"<p>The rapid advancement of photovoltaic technologies has intensified the demand for lightweight, low-cost and visually seamless solar cells for next-generation applications, including building-integrated photovoltaics (BIPV), electric vehicles (EVs), portable electronics and semi-transparent energy-harvesting surfaces. Among emerging technologies, ultrathin and semitransparent perovskite solar cells have attracted significant attention due to their exceptional power conversion efficiencies, high optical tunability and compatibility with flexible and transparent substrates. This review paper critically evaluates semitransparent perovskite solar cells (ST-PSCs) by systematically linking absorber thickness and composition, micro structured architectures, transparent electrodes, optical performance, stability and application requirements. Rather than assessing devices solely based on power conversion efficiency (PCE), the review provides a comprehensive comparison using PCE alongside average visible transmittance (AVT), light utilization efficiency (LUE), colour-rendering index and reported stability conditions. It distinguishes between transparent, semitransparent, ultrathin and micro structured PSC architectures and explains the physical mechanisms governing the fundamental trade-off between photovoltaic efficiency and optical transparency. Transparent electrodes are critically assessed in terms of their electrical, optical, mechanical, manufacturing and stability characteristics, whereas the specific requirements of BIPV are examined at both device and module levels. Recent experimental and theoretical advances are further reviewed to identify practical pathways towards scalable, durable and visually acceptable photovoltaic windows and other transparent energy-harvesting surfaces.</p>","PeriodicalId":13408,"journal":{"name":"Iet Optoelectronics","volume":"20 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/ote2.70045","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149205938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optical Half Adder Based on Linear Optical Interference Using a Multimode Interference Structure","authors":"Yohei Aikawa,&nbsp;Hiroyuki Uenohara","doi":"10.1049/ote2.70044","DOIUrl":"10.1049/ote2.70044","url":null,"abstract":"<p>With the rapid growth of artificial intelligence, photonic computing has attracted increasing attention as an energy-efficient alternative to electronic computing. Optical half adders have been realized using semiconductor optical amplifiers (SOAs), plasmonic waveguides, photonic crystals (PhCs) and inverse-designed photonic structures. However, many existing approaches rely on nonlinear effects, metallic absorption, limited complementary metal oxide semiconductor (CMOS) compatibility or computationally intensive optimization. In this paper, a two-bit optical half adder based on passive linear optical interference is proposed. The device consists of a four-input, three-output silicon-on-insulator (SOI) waveguide circuit employing multimode interference structures and Y-branch waveguides. It operates with two binary phase-shift keying (BPSK) input signals and a single probe light, simultaneously performing XOR and AND logic operations. The device was analytically designed, fabricated on an SOI platform and experimentally demonstrated. Measured extinction ratios of 6.8 and 5.5 dB were obtained for the XOR and AND outputs, respectively. The proposed MMI-based device offers low power consumption, low insertion loss, low design complexity and CMOS compatibility, making it a promising building block for future photonic computing systems.</p>","PeriodicalId":13408,"journal":{"name":"Iet Optoelectronics","volume":"20 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/ote2.70044","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149021181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine Learning-Based Radio Environment Map Estimation for Indoor Visible Light Communication","authors":"Helena Serpi,&nbsp;Christina (Tanya) Politi","doi":"10.1049/ote2.70043","DOIUrl":"https://doi.org/10.1049/ote2.70043","url":null,"abstract":"<p>This paper presents a machine learning-based methodology for constructing optical radio environment maps (REM) for indoor visible light communication (VLC) systems, explicitly positioned as an empirical benchmarking and evaluation framework. First, the REM estimation is evaluated on configurable simulated datasets generated by a physics-based indoor VLC simulator, and then the selected method is benchmarked against alternative learning and interpolation-based methods on experimental measurements. The evaluation of decision trees and multilayer perceptron (MLP) models on simulator RSS datasets for different room geometries and transmitter configurations shows that tuning sample size, epochs and batch size allows MLPs to achieve superior accuracy-performance trade-offs. Subsequently, a comprehensive comparison of MLP against kernel-based regressors, interpolation methods and neural architectures (CNN and U-Net) reveals that although spatial extrapolation degrades performance, multiple models achieve comparable interpolation accuracy. Specifically, MLP optimally balance accuracy and computational efficiency, training roughly three times faster than convolutional architectures. Furthermore, data augmentation using SMOGN and Gaussian process regression (GPR) was investigated, demonstrating that GPR-based synthetic data can reduce required real-world measurements by up to 83% without compromising prediction accuracy. These results confirm the practical viability of data-driven REMs for indoor VLC applications such as network planning, localisation and digital twins.</p>","PeriodicalId":13408,"journal":{"name":"Iet Optoelectronics","volume":"20 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/ote2.70043","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148994055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hybrid VLC–IR Communication System With Beam-Steered Uplink and Turbo Coding Under Mobility","authors":"Saeed Ahmed Ansari","doi":"10.1049/ote2.70041","DOIUrl":"https://doi.org/10.1049/ote2.70041","url":null,"abstract":"<p>We evaluate a hybrid visible light communication (VLC) downlink and beam-steered infrared (IR) uplink in a 5 × 5 × 3 m indoor room under line-of-sight (LOS), non-line-of-sight (NLOS) and user-mobility scenarios. A MATLAB-based framework is used to analyse bit error rate (BER), signal-to-noise ratio (SNR), spectral efficiency, received power and delay metrics. The evaluation follows classical indoor optical wireless channel models with explicitly parameterised noise, reflection and mobility assumptions to ensure reproducibility. With Turbo coding, the BER falls below <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>1</mn>\u0000 <msup>\u0000 <mn>0</mn>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>3</mn>\u0000 </mrow>\u0000 </msup>\u0000 </mrow>\u0000 <annotation> $1{0}^{-3}$</annotation>\u0000 </semantics></math> once the electrical SNR exceeds 10 dB, following the theoretical BPSK–AWGN waterfall trend whilst exhibiting a clear coding gain relative to the uncoded BPSK benchmark under both LOS and NLOS conditions. VLC achieves high SNR and spectral efficiency near the room centre but degrades towards boundaries due to multipath and shadowing. The IR uplink with adaptive beam steering provides more uniform coverage and robustness in mobility and NLOS conditions. A qualitative comparison with RF systems highlights differences in spectrum availability, interference characteristics and spatial confinement. These findings confirm the feasibility of hybrid VLC–IR systems for smart-building and indoor IoT scenarios. Future extensions will explore machine-learning-based steering and integration with IEEE 802.11bb standards to support large-scale deployment.</p>","PeriodicalId":13408,"journal":{"name":"Iet Optoelectronics","volume":"20 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/ote2.70041","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148783925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction to “Optical Digital-to-Analog Converters (oDACs): A Solution to Overcome the Limitations of Conventional High-Speed Optical Transmitters”","authors":"","doi":"10.1049/ote2.70042","DOIUrl":"https://doi.org/10.1049/ote2.70042","url":null,"abstract":"<p>K. Moschopoulos, V. Tsourtis, S. Sygletos, et al., “Optical Digital-to-Analog Converters (oDACs): A Solution to Overcome the Limitations of Conventional High-Speed Optical Transmitters,” <i>IET Optoelectronics</i> (2026): e70021, https://doi.org/10.1049/ote2.70021.</p><p>Shortly after publication, the authors reached out to inform us of an error in the authors' contributions.</p><p>The correct author contributions are listed as follows:</p><p>“Konstantinos Moschopoulos led the writing of the manuscript and contributed to all simulation studies. Stylianos Sygletos revised the manuscript and performed the simulation studies of Section 4. Vassilis Tsourtis contributed to Section 5 by providing electronic expertise. Elias Giacoumidis and André Richter assisted with the simulations for Section 3. Moshe Nazarathy and Ioannis Tomkos conceived the oDAC concept and contributed to the overall revisions and proofreading of the document. Ioannis Tomkos provided the funding as a PI of FLEX-SCALE.”</p><p>The authors apologize for this error.</p>","PeriodicalId":13408,"journal":{"name":"Iet Optoelectronics","volume":"20 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/ote2.70042","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148753432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Image-Based Detection in an Angle-Interrogation Surface Plasmon Resonance Refractive Index Sensor Using a Simple Bilayer-Coated Prism","authors":"Masoumeh Feyzian,&nbsp;Mahdi Shayganmanesh,&nbsp;Mohammad Hossein Mahdieh","doi":"10.1049/ote2.70040","DOIUrl":"https://doi.org/10.1049/ote2.70040","url":null,"abstract":"<p>In this paper, we report the design and fabrication of a surface plasmon resonance (SPR) sensor for measuring variations in the refractive index of liquid solutions. The sensor employs a simple Kretschmann configuration in which only two layers of chromium and gold with optimised thicknesses were deposited on a prism and the laser beam reflection is evaluated via image processing instead of photodiode. A computer simulation programme was developed to predict resonance curves by analysing the effect of key parameters. To validate the system, calibration experiments were carried out using sugar solutions with concentrations of 0%, 5%, 15% and 20%. The results show that the implemented SPR sensor achieves a sensitivity of 165.16 deg/RIU, an FWHM of 7 deg, a quality factor of 25.6 RIU⁻¹ and a dynamic range of 1.00–1.37 RIU. These findings demonstrate the reproducibility and robust performance of the proposed setup, highlighting its potential as a low-cost and reliable platform for refractive index sensing in chemical, biological and industrial applications.</p>","PeriodicalId":13408,"journal":{"name":"Iet Optoelectronics","volume":"20 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/ote2.70040","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148173982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Terahertz Metamaterial Sensor With Graphene Resonator for Ethanol‒Water Concentration Sensing","authors":"Roktim Barua,&nbsp;Muhammad Asad Rahman,&nbsp;Sumaia Jahan Mishu,&nbsp;Nipa Dhar","doi":"10.1049/ote2.70038","DOIUrl":"https://doi.org/10.1049/ote2.70038","url":null,"abstract":"<p>This paper presents a terahertz metamaterial sensor designed to detect changes in ethanol concentration in water, which is highly relevant for chemical analysis, food safety, and biomedical sensing applications. The sensor comprises three distinct layers: a graphene-based resonator at the top, an intermediate dielectric spacer layer, and a metallic layer at the bottom, forming a compact and efficient absorber structure. The sensor exhibits an absorption of 99% at a resonant frequency of 6.08 THz for 0% ethanol concentration, with a quality (Q) factor of 31.48. Furthermore, the effects of various graphene material parameters, such as chemical potential and relaxation time, on absorption performance have been systematically investigated through numerical simulations to achieve an optimal response and enhanced sensing performance. As the ethanol concentration increases, the resonant frequency gradually shifts to lower values due to the rise in the effective refractive index near the sensing region, enabling reliable refractive index discrimination. The proposed sensor achieves a high figure of merit (FOM) of 12.4, indicating excellent resolution for refractive index detection, along with a sensitivity of 2369 GHz/RIU and a full width at half maximum (FWHM) of 190 GHz. These results demonstrate that the proposed graphene-based terahertz sensor offers a promising platform for high-resolution, noncontact liquid sensing in the terahertz frequency regime.</p>","PeriodicalId":13408,"journal":{"name":"Iet Optoelectronics","volume":"20 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/ote2.70038","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148173833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rigorous Performance Characterisation of AI-Enhanced 6G Underwater Optical Wireless Networks: Link Budget Correction and Empirical Gain Validation","authors":"Yousuf Islam,&nbsp;Md. Imam Hossain,&nbsp;Md. Jehadul Islam Mony","doi":"10.1049/ote2.70039","DOIUrl":"https://doi.org/10.1049/ote2.70039","url":null,"abstract":"<p>The incorporation of sixth-generation (6G) technologies into underwater optical wireless communication (UWOC) holds the potential for Gbps-class maritime connectivity; however, the field is presently affected by significant overestimations in the systematic link budget found in existing literature. Certain modelling discrepancies found in the literature—such as using absorption instead of total beam attenuation, assumptions of coherent detection in IM/DD systems, neglecting the Hermitian symmetry factor in DCO–OFDM throughput and the unexamined application of laboratory-measured AI gains to analytical budgets—result in range forecasts that surpass physically consistent predictions by two to three times. This study introduces a revised intensity-modulated direct-detection (IM/DD) framework for DC-biased optical OFDM (DCO–OFDM) that corrects for each of these issues. The net throughput is rigorously calculated to be 776 Mbps for QPSK, explicitly considering the 511 usable subcarriers dictated by Hermitian symmetry in a 1024-point transform. Symbol-level Monte Carlo simulations across 40.9 million bits per distance point confirm the analytical BER predictions within 0.3 orders of magnitude at error rates relevant to operational use, whereas a controlled experiment with an MLP equaliser shows that, in a known, stationary and linear LTI channel with perfect channel state information (CSI) provided to the minimum mean squared error (MMSE), the gains of +4 to −6 dB that are often associated with deep learning equalisers diminish to zero. This highlights the necessity of channel uncertainty, transmitter nonlinearity and rapid fading as essential conditions for achieving the benefits of AI-assisted equalisation. The revised framework offers a self-validated range of 44.8 m (only with MRC diversity) and a projected range of 46 m (assuming literature-based CSI prediction) at BER <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>&lt;</mo>\u0000 <mn>1</mn>\u0000 <msup>\u0000 <mn>0</mn>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>9</mn>\u0000 </mrow>\u0000 </msup>\u0000 </mrow>\u0000 <annotation> ${&lt; } 1{0}^{-9}$</annotation>\u0000 </semantics></math> in clear ocean conditions. System-level evaluations of proton-exchange membrane fuel cells indicate that AI-driven load smoothing yields minimal efficiency improvements (&lt; 0.2%) at average AUV power levels, confirming that the 1.8× endurance benefit over lithium-ion batteries is solely due to energy density rather than intelligent power management. By providing fully disclosed parameters and empirical validation for every asserted advantage, this research establishes a scientifically credible benchmark for future calibration of 6G subsea architectures.</p>","PeriodicalId":13408,"journal":{"name":"Iet Optoelectronics","volume":"20 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/ote2.70039","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148173832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Position Estimation Method Using RGB Values of LED Colour Temperature in a Fuzzy Logic System","authors":"Myung-Hoon Sung,&nbsp;Wu-Sung Choi,&nbsp;Jun-Hee Lee,&nbsp;Jae-won Kim,&nbsp;Yong-Gyu Jeong,&nbsp;So Hyeon Jo,&nbsp;Joo Woo,&nbsp;Han Byeol Bae,&nbsp;Suk Kun Jee,&nbsp;Jae Hoon Jeong,&nbsp;Teak Young Seung","doi":"10.1049/ote2.70035","DOIUrl":"https://doi.org/10.1049/ote2.70035","url":null,"abstract":"<p>Localisation in tunnel environments remains a challenging problem due to the limited availability of GPS signals. To address this issue, this study presents a localisation system that exploits the colour temperature characteristics of indoor LED lighting. Unlike previous LED-based localisation studies that rely on large colour temperature differences and limited experimental areas, the proposed approach intentionally reduces the colour temperature gap between LEDs and expands the experimental environment to better reflect realistic tunnel conditions. The proposed system analyses both chromaticity and frequency components of LED signals to estimate position. Experiments conducted in a controlled environment simulating tunnel conditions demonstrate that the proposed method achieves positioning accuracy within 10 cm over an expanded two-dimensional area. Specifically, the <i>X</i>-axis coordinate is estimated based on LED colour temperature information, whereas the <i>Y</i>-axis coordinate is inferred from frequency-domain features extracted using bandpass filtering and frequency component ratio (FCR). These results indicate that reliable localisation can be achieved using practical LED configurations even in environments where GPS signals are unavailable.</p>","PeriodicalId":13408,"journal":{"name":"Iet Optoelectronics","volume":"20 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/ote2.70035","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148173827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":13408,"journal":{"name":"Iet Optoelectronics","volume":"20 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148092878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}