Results in OpticsPub Date : 2025-04-08DOI: 10.1016/j.rio.2025.100825
Thi-Hanh-Thu Vu , Quang-Khoi Nguyen
{"title":"Precision optical model of asymmetry emission band of red light emitting diodes and its application in improving the color rendering index of white LEDs","authors":"Thi-Hanh-Thu Vu , Quang-Khoi Nguyen","doi":"10.1016/j.rio.2025.100825","DOIUrl":"10.1016/j.rio.2025.100825","url":null,"abstract":"<div><div>We have proposed and demonstrated a<!--> <!-->precision<!--> <!-->optical model for<!--> <!-->red light-emitting diodes and applied this model to improve the color rendering index of phosphor-converted white light-emitting diodes. The inherent asymmetry properties of red light emission bands have been conquered and effectively modeled. The accuracy of the red light optical model is confirmed with the experimental<!--> <!-->spectrum and verified by normalized cross-correlation. In an application, the<!--> <!-->Gaussian functions-based mathematical<!--> <!-->model is applied to simulate the emission spectrum of white light with and without adding red light. The supplement of red light is optimized<!--> <!-->to improve the CRI index of output white light. As a result, the color performance of white LEDs is improved when the CRI value<!--> <!-->significantly<!--> <!-->increases from 79 to 93 by adding an optimized amount of red light. The effect of added red light on white-LEDs properties has been investigated including correlated color temperature,<!--> <!-->output lumen, CIE-chromaticity coordinates, and luminous efficiency of radiation. In addition, the effect of adding red light on color rendering quality of output white light is studied with the IES TM 30–18 application.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"21 ","pages":"Article 100825"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143816938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Results in OpticsPub Date : 2025-04-05DOI: 10.1016/j.rio.2025.100822
Md. Murad Kabir Nipun , Md. Jahedul Islam , Md. Moniruzzaman
{"title":"A triple-band metamaterial absorber for gas sensing and refractive index detection through enhanced FOM and Q-factor performance in the THz regime","authors":"Md. Murad Kabir Nipun , Md. Jahedul Islam , Md. Moniruzzaman","doi":"10.1016/j.rio.2025.100822","DOIUrl":"10.1016/j.rio.2025.100822","url":null,"abstract":"<div><div>In this paper, a new micro-arranged triple band interconnected oval-shaped split ring with an external split circle symmetrical metamaterial absorber (MMA) is discussed. This design contains three layers where lead glass is sandwiched between two copper layers as a resonator surface and ground, which has a strong ability to identify the variation of refractive index for different gas sensing through THz frequency spectral analysis. The working frequency of the proposed absorber is 9 to 10 terahertz (THz) where the three absorption peaks are having 99.95%, 96.42%, and 99.98% absorptions at 9.42 (f1), 9.86 (f2), and 10.03 (f3) THz, respectively. The figure of merit (FOM) of the proposed MMA having value of 15.45, 23.82, and 29.87shows progressively higher sensing application and precisely identify small changes in refractive index. To measure the Sensitivity, refractive index (n) has been varied from 1 to 1.05 and the results are 2.016, 2.556 and 1.41 THz per refractive index unit where these values indicate an effective sensitivity for detecting small changes in refractive index. The quality factors (Q-factors) of this triple band MMA are 72.53, 92.11, and 213.24 indicating sophisticated accuracy and better capability to spot and respond to minute changes in its environment. This MMA shows a great polarization independency as it has symmetrical construction. To explore the absorption and sensitivity property of this unique MMA, several parametric simulations have been done such as surface current, different gas layers and in addition permittivity and permeability are also analyzed. As a whole, this MMA shows versatility, with excellent FOM values and Q-factors, making it a reliable option for both wide-band sensing as well as high-precision sensing. This ability to react to changes in refractive index makes it a brilliant candidate for sensing applications in fields such as environmental monitoring, clinical examination, and chemical sensing.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"21 ","pages":"Article 100822"},"PeriodicalIF":0.0,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143828989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Results in OpticsPub Date : 2025-04-04DOI: 10.1016/j.rio.2025.100818
Inam Vulindlela , Athandwe M. Paca , Edson L. Meyer , Mojeed A. Agoro , Nicholas Rono
{"title":"Design and computational investigation of PbS-based bifacial quantum dot-sensitized solar cells","authors":"Inam Vulindlela , Athandwe M. Paca , Edson L. Meyer , Mojeed A. Agoro , Nicholas Rono","doi":"10.1016/j.rio.2025.100818","DOIUrl":"10.1016/j.rio.2025.100818","url":null,"abstract":"<div><div>Recently, numerical simulation of solar cells has drawn significant scientific interest in photovoltaics because of its potential to reduce research expenses and time before laboratory fabrication of solar cells. In this study, we investigated the performance of a solar cell with a general configuration of FTO/ETL/PbS/P3HT/Au using SCAPS-1D simulation software (version 3.3.10). Several electron transport layer (ETL) materials, including TiO<sub>2</sub>, ZnO, tungsten disulfide (WS<sub>2</sub>), tin (IV) oxide, and buckminsterfullerene (C<sub>60</sub>), were initially tested. After optimization, WS<sub>2</sub> was identified as the best ETL material, exhibiting a power conversion efficiency (PCE) of 4.91 %. Subsequently, the WS<sub>2</sub>-based device architecture was used to test various hole transport layer (HTL) materials, including organic materials like poly(3-hexylthiophene) (P3HT) and 2,2′,7,7′-Tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9′-spirobifluorene (spiro-OMeTAD), as well as inorganic materials such as CuSCN, Cu<sub>2</sub>O, and copper zinc tin selenide (CZTSe). Among the HTLs tested, CZTSe exhibited the highest PCE of 13.47 %. The ideal defect density for each device was maintained at 1.0 × 10<sup>14</sup> cm<sup>−3</sup>. Furthermore, a bifacial version of the device, Ag/FTO/WS2/PbS/CZTSe/Au, was simulated, showing a bifacial factor (BF) for PCE of 81.74 % and a bifacial gain (BG) of 81.89 %. Based on the simulation results, we predict that the PbS-based bifacial solar cell can achieve a PCE greater than 24 %, demonstrating its potential for high-efficiency solar energy conversion. This study systematically optimized both the electron and hole transport layers in PbS-based bifacial solar cells, demonstrating the potential of WS<sub>2</sub> as an effective electron transport material and CZTSe as a promising hole transport material for achieving high-efficiency performance.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100818"},"PeriodicalIF":0.0,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143769146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Results in OpticsPub Date : 2025-04-01DOI: 10.1016/j.rio.2025.100816
Shiva Khani , Mohsen Hayati
{"title":"High resolution refractive index and temperature sensor with Fano resonance in disk and parenthesis-shaped plasmonic cavities","authors":"Shiva Khani , Mohsen Hayati","doi":"10.1016/j.rio.2025.100816","DOIUrl":"10.1016/j.rio.2025.100816","url":null,"abstract":"<div><div>A surface plasmon-based sensor with high resolution for refractive index and temperature sensing is proposed in this work. This structure comprises a disk cavity (DC) coupled to four parenthesis-shaped cavities (PSCs) and two plasmonic waveguides. The finite difference time domain (FDTD) numerical method is utilized to study the suggested sensor’s performance. The frequency response of the suggested sensor has a Fano resonance (FR) mode with a sharp edge at the wavelength range of 700–800 nm which is suitable for sensing applications. The generated FR mode is tunable, and its location is tuned by varying the radii of DC and PSCs. Results show that the maximum sensitivity (S<sub>λ</sub>) of 735 nm/RIU is obtained, and the FoM* value of 25,357 RIU<sup>−1</sup> is also realized for the suggested plasmonic sensor. As an application for the sensor topology, it is simulated again using the FDTD method for different ambient temperatures. The suggested sensor achieves a relatively high-temperature S<sub>λ</sub> of about 0.285 nm/<sup>o</sup>C. Due to the noteworthy and simple structure of the suggested sensor and its high FoM*, it may be an appropriate candidate for optical integrated circuits, especially in high-sensitive sensors.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100816"},"PeriodicalIF":0.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143760982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Results in OpticsPub Date : 2025-03-31DOI: 10.1016/j.rio.2025.100824
Marco Laurence M. Budlayan , Dina C. Palangyos , Jonathan N. Patricio , Susan D. Arco , Raphael A. Guerrero
{"title":"Tunable optical beam focusing using static water droplets on an electrospun polymer fiber","authors":"Marco Laurence M. Budlayan , Dina C. Palangyos , Jonathan N. Patricio , Susan D. Arco , Raphael A. Guerrero","doi":"10.1016/j.rio.2025.100824","DOIUrl":"10.1016/j.rio.2025.100824","url":null,"abstract":"<div><div>This work explores the use of static water microdroplets on a microfiber to vary the width of an optical beam. Varying the water droplet volume changes the beam width without replacing any optical components. A surface derived from glass deposited with polyvinyl chloride (PVC) microfibers <em>via</em> electrospinning was used to sustain the droplet shape on the surface. Scanning electron microscopy revealed the presence of randomly intertwined microfibers with diameters of less than 3 µm which afforded the surface a hydrophobic property. A decrease in the optical transmittance of the films and an increase in the water contact angle were also observed as fiber density increases. Results revealed an increase in the beam size with increasing droplet volume manifesting a defocusing or magnifying effect as the beam passed through the droplets. The beam maintained its Gaussian profile, confirming that the presence of the deposited fibers did not significantly alter the beam type. By using droplets with different liquid volumes (5–60 µL), we replicate the action of a convex lens with varying focal length.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100824"},"PeriodicalIF":0.0,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143746734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Results in OpticsPub Date : 2025-03-31DOI: 10.1016/j.rio.2025.100820
R. Girija , H. Singh , G. Abirami
{"title":"Noise estimation in medical images based on fast discrete curvelet transform via wrapping","authors":"R. Girija , H. Singh , G. Abirami","doi":"10.1016/j.rio.2025.100820","DOIUrl":"10.1016/j.rio.2025.100820","url":null,"abstract":"<div><div>These days, image processing is a developing field of study. Images have many contribution to research in a number of areas, including biomedical, security, education, and space. Digital images are inherently noisy during the processes of acquiring, coding, transmitting, and processing and the significant barrier is the problem of image corrupted brought on by noise. The two primary causes of the noise are either the transmission procedure from one location to another or the acquisition process itself. Denoising and categorising noise are crucial components of image analysis in medical field. However, there are numerous methods for modifying the image data in order to eliminate noise and restore image quality. A quick overview of the main types of noise is presented in this paper. The process of estimating noise and filtering to produce improved medical images is covered by the proposed framework. In this piece of work, several and various kinds of noise are estimated and detected: Gaussian noise, white noise, Brownian noise, salt-and-pepper, periodic and speckle noises.The proposed system reduces the noising factor in medical images based upon fast discrete curvelet transform (FDCT) via wrapping. MSE has been calculated between original and recovered image.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100820"},"PeriodicalIF":0.0,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Simulation and optimization of lead-free CH3NH3SnI3 perovskite solar cells using SCAPS-1D","authors":"Revathy Raghunathan Lekshmy , Ehsan Raza , Zubair Ahmad , Jolly Bhadra","doi":"10.1016/j.rio.2025.100823","DOIUrl":"10.1016/j.rio.2025.100823","url":null,"abstract":"<div><div>Recent advances in photovoltaic technology have made perovskite solar cells attractive prospects for future energy solutions. However, the presence of lead (Pb) in many perovskite materials causes environmental and health problems, limiting their practical utility. This work investigates the possibility of lead-free perovskite solar cells (PSCs) with CH<sub>3</sub>NH<sub>3</sub>SnI<sub>3</sub> as the absorber layer. CH<sub>3</sub>NH<sub>3</sub>SnI<sub>3</sub> is chosen for its advantageous qualities such as non-toxicity, good visible light absorption, and smaller band gap. The SCAPS-1D modeling tool was used to model these cells performance in the AM 1.5 G solar spectrum. The study looks at how varying absorber layer thicknesses, doping levels, defect densities, operating temperatures, back contact materials,series and shunt resistance affect the performance of the solar cell. The simulated device structure is FTO/TiO<sub>2</sub>/IDL/CH<sub>3</sub>NH<sub>3</sub>SnI<sub>3</sub>/Carbon, with TiO<sub>2</sub> as the electron transport layer (ETL) and CH<sub>3</sub>NH<sub>3</sub>SnI<sub>3</sub> as the absorber layer. At 300 K, the device exhibits an open-circuit voltage (Voc) = 0.886 V, a fill factor (FF) = 81.58 %, a short-circuit current density (Jsc) = 30.68 mA/cm<sup>2</sup>, and a power conversion efficiency (PCE) = 22.23 %.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"21 ","pages":"Article 100823"},"PeriodicalIF":0.0,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143834058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Results in OpticsPub Date : 2025-03-31DOI: 10.1016/j.rio.2025.100821
Vo Quang Sang, Pham Van Quan, Bui Dinh Bao
{"title":"Optimized Fresnel lens design for enhanced Passive infrared sensors in advanced security monitoring systems","authors":"Vo Quang Sang, Pham Van Quan, Bui Dinh Bao","doi":"10.1016/j.rio.2025.100821","DOIUrl":"10.1016/j.rio.2025.100821","url":null,"abstract":"<div><div>Passive Infrared (PIR) motion sensors are integral to modern residential and commercial security systems, valued for their reliability, cost-effectiveness, and ability to detect motion through infrared radiation. These systems typically employ Fresnel lenses to focus infrared signals onto pyroelectric detectors, thereby enhancing detection range and differentiating between dynamic objects and background noise. However, conventional coaxial Fresnel lens designs are hindered by uneven light intensity distribution, resulting in reduced sensitivity and non-uniform detection across the field of view. This paper presents a breakthrough<!--> <!-->non-coaxial Fresnel lens architecture<!--> <!-->that addresses these limitations through advanced optical design and optimization techniques. By redistributing infrared radiation uniformly across the sensor’s surface, the proposed design significantly enhances detection uniformity and sensitivity. The methodology leverages<!--> <!-->advanced ray tracing and optical simulation tools<!--> <!-->(Zemax Optics Studio) in both sequential and non-sequential modes to optimize key performance parameters such as light uniformity, focusing efficiency, and aberration minimization. The results reveal that the optimized Fresnel lens achieves superior performance in small-angle, high-gain, and short focal length applications, offering unprecedented consistency in motion detection. This innovative approach establishes a new benchmark for Fresnel lens design, enabling the development of next-generation PIR sensors for advanced security systems, with broader implications for imaging, automation, and renewable energy applications.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100821"},"PeriodicalIF":0.0,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143746626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Results in OpticsPub Date : 2025-03-25DOI: 10.1016/j.rio.2025.100808
M.E. Ateuafack , Pristina C. Kemayou , Paul V. Djaba , Lavoisier Wah , J.T. Diffo , L.C. Fai
{"title":"Unraveling energy dissipation dynamics in 2D coplanar magnonic cavities: Insights into mode interactions and resonance phenomena","authors":"M.E. Ateuafack , Pristina C. Kemayou , Paul V. Djaba , Lavoisier Wah , J.T. Diffo , L.C. Fai","doi":"10.1016/j.rio.2025.100808","DOIUrl":"10.1016/j.rio.2025.100808","url":null,"abstract":"<div><div>This study investigates the intricate dynamics of energy dissipation in a two-dimensional coplanar magnonic cavity structure, driven by the cavity Lenz effect. We examine the interactions between coupled photonic modes, specifically the dipole (D) and quadrupole (Q) modes, and a magnon mode within the system, aiming to uncover the mechanisms governing dissipation processes. Analysis of the transmission spectrum reveals a fascinating degeneracy between the perpendicular D-mode and the Q-mode, providing new insights into the interplay between dissipation and system behavior. Through theoretical exploration, we detail the resonance phenomena involving the magnon mode, the external photon bath frequency, and the microwave cavity mode, offering a deeper understanding of the complex energy loss dynamics. Our findings emphasize the importance of strategies to minimize energy dissipation and enhance light absorption in magnonic cavities, paving the way for advancements in nanoscale energy harvesting technologies. Moreover, reducing energy loss in these systems will facilitate the development of next-generation optoelectronic and electronic devices.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100808"},"PeriodicalIF":0.0,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143705685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Elaboration of spin coated deposition of tin oxide thin films: Effect of concentration","authors":"Hanane Meddas , Lakel Abdelghani , Dakhlaoui Amel , Bouaicha Saliha , Slatnia Randa , Aida Mohamed Salah Belahssen Okba","doi":"10.1016/j.rio.2025.100811","DOIUrl":"10.1016/j.rio.2025.100811","url":null,"abstract":"<div><div>Tin oxide (SnO<sub>2</sub>) thin films were deposited on glass substrates using a cost effective spin coating method. The effect of solution molarity on their microstructural, optical and electrical properties was investigated. For this purpose, solutions of tin chloride salt were prepared with various molarity in the range of 0.1 to 0.25 M. The synthetized films structure and morphology were characterized by different techniques such as: X-rays diffraction (XRD) and scanning electron microscopy (SEM). The optical and electrical properties were studied by mean of UV visible spectroscopy and four probes conductivity measurement. The XRD patterns of all samples revealed well-crystallized and pure SnO<sub>2</sub> films with tetragonal rutile structure. The SEM images reveal a smooth and dense film pinholes free. The optical analyses show that the films exhibit an optical transparency that reaches up to 98 % in the visible range and that the optical band gap decreases from 3.97 to 3.82 eV when the concentration increases from 0.1 to 0.25 M. The films electrical conductivity varies in the range from 76 to 100 (Ω.cm)<sup>-1</sup>. The largest figure of merit of 9.8 × 10<sup>-3</sup>, was measured in the films prepared at low solution concentration.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100811"},"PeriodicalIF":0.0,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143705684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}