Optik最新文献

{"title":"Integrated all-fiber-optic sensor based on FPI and MZI composite structures for temperature and strain measurement","authors":"Yinggang Liu,&nbsp;Xinyi Xu,&nbsp;Rui Zhou,&nbsp;Rui Li,&nbsp;Fei Li","doi":"10.1016/j.ijleo.2024.172111","DOIUrl":"10.1016/j.ijleo.2024.172111","url":null,"abstract":"<div><div>In this paper, a temperature and strain sensor based on fiber-optic Mach-Zehnder interferometer (MZI) cascaded with Fabry-Perot interferometer (FPI) is designed and fabricated. The integrated sensor structure consists of no-core fiber (NCF) sandwiched by two sections of multi-mode fiber (MMF), hollow-core fiber (HCF), and two single-mode fibers (SMF) which are cascaded at the ends of the MMF and the HCF. Due to the thermal expansion effect, thermo-optic and elasto-optic effects of fiber material, the increase of the temperature and strain will make the change of the transmission mode, which will cause the spectral fringes wavelength shifting with strain, and the intensity of the spectral fringes varying with temperature but not strain variations in multiple temperature ranges. The series experiments valid show that the sensor with integrated structure realizes the strain and temperature measurements in multiple temperature ranges, and the minimum and maximum temperature sensitivities are − 0.278 dBm/°C and − 0.670 dBm/°C in the temperature range of 68–86 °C and 123–141 °C, respectively. The strain sensitivity is 2.17 pm/με all over the measured range. The integrated sensor structure has the advantages of high sensitivity, multiple measuring ranges, simple manufacturing, and low cost, which has the potential to be applied in the field of the internal strain and temperature measurements of different structures.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"319 ","pages":"Article 172111"},"PeriodicalIF":3.1,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accounting for intensity variation within pixels of Shack-Hartmann wavefront sensors","authors":"Suman Sangiri ,&nbsp;Alfredo Dubra ,&nbsp;Vyas Akondi","doi":"10.1016/j.ijleo.2024.172107","DOIUrl":"10.1016/j.ijleo.2024.172107","url":null,"abstract":"<div><div>The accuracy of centroiding algorithms in Shack-Hartmann wavefront sensing is limited by the implicit approximation of uniform pixel illumination. Iterative centroiding algorithms are further limited by the consideration of full pixels to define the image domain for centroiding. Here, we demonstrate two practical and complementary approaches to mitigate both these sources of error. First, we consider partial or ‘fractional’ pixels to maintain centroiding area symmetry around the center of mass. Secondly, we propose methods to perform piece-wise polynomial interpolation to calculate intensity distribution within pixels, which is then used to estimate the centroid within each pixel area. This approach that accounts for intensity non-uniformity across pixels notably reduces centroid errors up to a factor of 5 across lenslet image widths ranging from 1.33 to 3.10 pixels full-width-half-maximum (FWHM). Consequently, wavefront sensing errors decrease from 14 % to 4 %, on average, for FWHM = 1.35 pixels, demonstrating a substantial benefit when the number of pixels per lenslet is minimized to enhance the signal-to-noise ratio or increase frame rate.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"319 ","pages":"Article 172107"},"PeriodicalIF":3.1,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optomechanical entanglement induced by backward stimulated Brillouin scattering","authors":"P. Djorwé ,&nbsp;A.-H. Abdel-Aty ,&nbsp;K.S. Nisar ,&nbsp;S.G.N. Engo","doi":"10.1016/j.ijleo.2024.172097","DOIUrl":"10.1016/j.ijleo.2024.172097","url":null,"abstract":"<div><div>We propose a scheme to generate robust optomechanical entanglement, i.e., the entanglement between a mechanical and an optical modes. This scheme is based on a Backward Stimulated Brillouin Scattering (BSBS) process, which is hosted within an optomechanical structure. Our benchmark system consists of an acoustic (mechanical) mode coupled to two optical modes through an electrostrictive (radiation pressure) effect. After determining the optimal acoustic parameters allowing the entanglement in our system, we have shown that both the acoustic coupling and the decay rate require a certain threshold from where the optomechanical entanglement is generated. For instance, to generate an optomechanical entanglement in our proposal, the strength of the used acoustic decay rate most exceed both the mechanical and optical decay rates, which is the figure of merit of our proposal. The generated entanglement is robust enough against thermal fluctuation. Our work provides a new scheme for entanglement generation based on BSBS effect, and can be extended to microwaves and hybrid optomechanical structures. Such a generated entangled states can be used for quantum information processing, quantum sensing, and quantum computing.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"319 ","pages":"Article 172097"},"PeriodicalIF":3.1,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization of C-like sandwich wall structure for high microwave transmission","authors":"Manal M. Al-Ali ,&nbsp;Abd Alghany Jaradat ,&nbsp;Ahmed M. Al-Khateeb ,&nbsp;Sami H. Mahmood","doi":"10.1016/j.ijleo.2024.172096","DOIUrl":"10.1016/j.ijleo.2024.172096","url":null,"abstract":"<div><div>A multilayered structure of five planar slabs ((Glass epoxy/PU Foam/Vacuum/PU Foam/Glass epoxy) was investigated for broadband microwave propagation. In this study, theoretical calculations of the transmittance, reflectance and absorbance characteristics of the multilayer structure were carried out using the ABCD transfer matrix method, and numerical calculations were obtained using the COMSOL Multiphysics simulation software. The propagation characteristics were investigated as a function of frequency up to the Ka-band and versus angle of incidence ranging from normal to grazing incidence. The results of the theory and simulation were in excellent agreement. The average transmittance for unpolarized or circularly polarized wave was 97% over the S to the K bands, whereas up to 86% transmission was observed at the end of the Ka-band. Higher than 95% transmission of incident waves with frequency 10 GHz was observed over a wide range of angles of incidence up to <span><math><mrow><mn>70</mn><mo>°</mo></mrow></math></span>, after which the transmittance decreased sharply to zero at a grazing incidence (<span><math><mrow><msub><mrow><mi>θ</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>=</mo><mspace></mspace><mn>90</mn><mo>°</mo></mrow></math></span>). The results revealed that the absorbance is negligibly small and the incident energy was either transmitted or reflected. The reflectance for both TE and TM wave modes increased appreciably in the angular range <span><math><mrow><mn>75</mn><mo>°</mo><mo>≤</mo><msub><mrow><mi>θ</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>≤</mo><mn>90</mn><mo>°</mo></mrow></math></span> and approached 100% at grazing incidence. The curves of the reflectance versus angle of incidence for representative frequencies in the S and X bands revealed a Brewster-like effect for the TM wave mode, while the reflectance of the TE mode varied monotonically, without showing a minimum characteristic of a Brewster-like reflectionless condition.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"318 ","pages":"Article 172096"},"PeriodicalIF":3.1,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142593556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel reddish-orange emitting BaBPO5:Eu3+ phosphor for n-UV warm white-LEDs: Synthesis and study of structural and spectroscopic investigations","authors":"T. Chandra Mohan ,&nbsp;T. Raghu Raman ,&nbsp;K. Venkata Rao ,&nbsp;P. Sai Dinesh ,&nbsp;Y.C. Ratnakaram","doi":"10.1016/j.ijleo.2024.172103","DOIUrl":"10.1016/j.ijleo.2024.172103","url":null,"abstract":"<div><div>A novel reddish-orange emitting 2Ba_2-xO-B₂O₃-P₂O₅:xEu³⁺ (x= 0.04, 0.06, 0.08, 0.10, 0.12 and 0.14 mol%) phosphor with different concentrations of Eu³⁺ ions were synthesized through high temperature solid-state reaction technique. The crystal structure has been studied by X-ray diffraction technique for all the concentrations of Eu³⁺ ions. The morphology and elemental analysis of the optimal ∼0.1 mol% concentration was examined by the SEM-EDS images. The functional groups were analysed by the FTIR characterization technique. The thermal properties were studied by the TGA-DSC analysis. The energy band gap of all the samples were analysed by using UV–VIS DRS technique. The photoluminescence properties of BaBPO₅:Eu³⁺ phosphor with different concentrations of Eu³⁺ ions were investigated at λ_em = 611 nm and λ_ex = 394 nm. Variation in emission intensity with Eu³⁺ ion concentrations, phonon side bands, multi-phonon relaxation rate and energy transfer mechanisms were studied. The BaBPO₅:Eu³⁺ phosphors exhibit characteristic emission peaks corresponding to ⁵D₀ → ⁷F_J (<em>J</em> = 0, 1, 2, 3, 4) transitions of Eu³⁺ ions under n-UV excitation. Among all the transitions, ⁵D₀ → ⁷F₁ (593 nm) transition shows higher intensity and asymmetric ratio (R₂₁) for all concentrations of Eu³⁺ ions were calculated. The lifetimes of ⁵D₀ level of Eu³⁺ ions in BaBPO₅: Eu³⁺ phosphor were calculated by using fluorescent decay curve analysis. The CIE color coordinates reveal, reddish-orange emission in the low CCT range. These findings imply that BaBPO₅: 0.1Eu³⁺ phosphor is a promising candidate for solid-state lighting applications as well as phosphor-converted warm w-LEDs.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"318 ","pages":"Article 172103"},"PeriodicalIF":3.1,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142593461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Autoencoder-based image fusion network with enhanced channels and feature saliency","authors":"Hongmei Wang ,&nbsp;Xuanyu Lu ,&nbsp;Ze Li","doi":"10.1016/j.ijleo.2024.172104","DOIUrl":"10.1016/j.ijleo.2024.172104","url":null,"abstract":"<div><div>The existing deep learning based infrared and visible image fusion technologies have made significant progress, but there are still many problems need to be solved, such as information loss (targets and texture, etc.) of both infrared and visible images, noise and artifacts existing in fused image. To address these issues in fusion, an infrared and visible image fusion method based on autoencoder network is proposed in this paper. Firstly, novel enhanced channels are designed and input parallelly with source images into the network to enhance the specific features and reduce information loss in feature fusion. Then, the feature maps are obtained by the encoder. Next, a feature fusion method based on feature saliency is proposed, using a pre-trained classifier to measure the saliency of features, and the fused image is obtained by the decoder finally. Experimental results demonstrate that the targets are obvious and the textures are plentiful in the fused images generated by the proposed method. Also, the objective metrics of the proposed method are higher than the state of the art methods, which demonstrate that the proposed method is effective to fuse the infrared and visible images.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"319 ","pages":"Article 172104"},"PeriodicalIF":3.1,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of freeform elements with a large exit pupil for AR display","authors":"Olga Afanaseva,&nbsp;Artem Solomashenko,&nbsp;Maria Shishova,&nbsp;Larisa Timashova,&nbsp;Gaik Sagatelyan,&nbsp;Ivan Tsyganov","doi":"10.1016/j.ijleo.2024.172101","DOIUrl":"10.1016/j.ijleo.2024.172101","url":null,"abstract":"<div><div>This work presents an augmented reality display consisting of two freeform lenses. The first lens is composed of two aspherical polished surfaces and one plane surface, while the second lens acts as a compensator to allow distortion-free viewing of the surrounding area. One benefit of this design is the large size of the exit pupil, reaching up to 12 mm, and the low distortion value of 1.63 %. The optics has a thickness of 22 mm and is compatible with 0.49-in. diagonal displays. The field of view is limited to 28°, which is sufficient for various augmented reality applications.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"319 ","pages":"Article 172101"},"PeriodicalIF":3.1,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of complex instability in a Thulium-doped figure-eight fiber laser including a polarization-imbalanced NOLM with no polarization control.","authors":"L.A. Rodríguez-Morales ,&nbsp;O. Pottiez ,&nbsp;I. Armas-Rivera ,&nbsp;L.M. González-Vidal ,&nbsp;M. Durán-Sánchez ,&nbsp;M.V. Hernández-Arriaga ,&nbsp;M. Bello-Jiménez ,&nbsp;J.P. Lauterio-Cruz ,&nbsp;H.E. Ibarra-Villalon ,&nbsp;J.C. Hernandez-Garcia","doi":"10.1016/j.ijleo.2024.172100","DOIUrl":"10.1016/j.ijleo.2024.172100","url":null,"abstract":"<div><div>This study proposes a Thulium-doped figure-eight (F8) fiber laser design to be used as a platform to explore complex dynamics in passively mode-locked fiber laser systems. The proposed scheme incorporates a polarization-imbalanced nonlinear optical loop mirror (PI-NOLM) without a polarizer in the ring section. The absence of a polarizer prevents controlling the polarization state at the PI-NOLM input, which in turn allows the PI-NOLM switching power to vary dynamically during the laser operation. This leads to an intermittent noise-like pulse (NLP) operation, which is affected by complex instability in the form of non-periodic Q-switched-like behavior. Using real-time time-domain mapping techniques, we get a deep insight into the laser intricate dynamics, which involves not only NLPs, but also solitons and quasi-continuous-wave components with their subtle interactions. This study highlights the importance of the PI-NOLM in F8 laser schemes for the study and understanding of complex dynamics in Thulium-doped fiber lasers, which have been less extensively studied compared to other rare-earth-doped lasers. Our findings will contribute to the optimization and design of advanced laser systems for various scientific and industrial applications.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"318 ","pages":"Article 172100"},"PeriodicalIF":3.1,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142579007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Holographic solar concentrator with wide band using multi-wavelength transmission grating","authors":"Hui-Ying Wu ,&nbsp;Chang-Won Shin ,&nbsp;Ki-Chul Kwon ,&nbsp;Kwon-Yeon Lee ,&nbsp;Sang-Keun Gil ,&nbsp;Nam Kim","doi":"10.1016/j.ijleo.2024.172106","DOIUrl":"10.1016/j.ijleo.2024.172106","url":null,"abstract":"<div><div>A multi-wavelength holographic grating using photopolymer is presented for a holographic solar concentrator system. Currently, volume holographic optical elements (HOEs) have been proposed for application in solar concentrators due to their advantages, such as lightweight, selective wavelength, and passive tracking. However, their efficiency depends on the central wavelength, which is determined by both the recording material and the recording angle. In this work, a transmission holographic grating with multiple wavelengths is proposed to enhance the performance of holographic solar concentrator systems. The diffraction efficiency and spectral range are significant factors in determining the concentrated efficiency of solar energy. The optimal efficiency of transmission grating is derived based on the optical characteristics of the photopolymer and the wavelength selectivity is then analyzed to compare the concentrated efficiency. The experimental results indicate that the dichromatic transmission grating with an average diffraction efficiency of 70 % and a wavelength band of 278 nm has a concentrated efficiency of 48.7 %. Compared to monochromatic and trichromatic holographic grating, dichromatic grating can concentrate more energy with a wider spectral band.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"318 ","pages":"Article 172106"},"PeriodicalIF":3.1,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142593462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bio-calcium oxide derived from eggshell-titanium dioxide@graphene oxide for photodegradation of dyes and antibacterial activities","authors":"Nguyen Huu Hieu ,&nbsp;Ton That Buu ,&nbsp;Nguyen Duy Hai ,&nbsp;Vo Minh Quan ,&nbsp;Bo Khanh Ngoc ,&nbsp;Dang Hai Minh Tam ,&nbsp;Nguyen Thanh Hoai Nam ,&nbsp;Le Gia Han ,&nbsp;Mai Thanh Phong","doi":"10.1016/j.ijleo.2024.172099","DOIUrl":"10.1016/j.ijleo.2024.172099","url":null,"abstract":"<div><div>The utilization of calcium oxide (CaO) derived from calcined eggshells is considered a primary source of materials for semiconductor incorporation, which is a facile and environmentally friendly method. This work introduces a novel composite, namely calcium oxide-titanium dioxide@graphene oxide (CaO-TiO₂@GO) with photodegradation efficiency of various organic pollutants such as crystal violet (CV), malachite green (MG), rhodamine B (RhB), and methyl orange (MO). The results showed that the synergistic efficiency of the combination of GO and CaO-TiO₂ increased the adsorption-photodegradation efficiency with the removal of CV, MG, RhB, and MO of 99.72, 99.41, 97.21, and 80.09 %, respectively. The kinetics of dye photodegradation follows a pseudo-first-order kinetics model, the reusability toward CV removal reaches over 85 % after 5 cycles, and the free radical scavenging experiment identifies that the •O₂⁻ plays a major role in the photodegradation mechanism. In addition, the fundamental antibacterial performance toward strains of <em>Pseudomonas aeruginosa</em> and <em>Bacillus subtilis</em> was reported with antibacterial inhibition diameters of 12.1 and 11.2 mm, respectively.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"318 ","pages":"Article 172099"},"PeriodicalIF":3.1,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142579008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}