Journal Description
Photonics
Photonics
is an international, scientific, peer-reviewed, open access journal on the science and technology of optics and photonics, published monthly online by MDPI.
- Open Access— free for readers, with article processing charges (APC) paid by authors or their institutions.
- High Visibility: indexed within Scopus, SCIE (Web of Science), Inspec, CAPlus / SciFinder, and other databases.
- Journal Rank: JCR - Q2 (Optics)
- Rapid Publication: manuscripts are peer-reviewed and a first decision is provided to authors approximately 14.8 days after submission; acceptance to publication is undertaken in 2.6 days (median values for papers published in this journal in the first half of 2024).
- Recognition of Reviewers: reviewers who provide timely, thorough peer-review reports receive vouchers entitling them to a discount on the APC of their next publication in any MDPI journal, in appreciation of the work done.
- Companion journal: Lights.
Impact Factor:
2.1 (2023);
5-Year Impact Factor:
2.1 (2023)
Latest Articles
A Fast Solution of the Dynamic Rate Equation for a High-Power Fiber Laser
Photonics 2024, 11(9), 881; https://doi.org/10.3390/photonics11090881 (registering DOI) - 19 Sep 2024
Abstract
In the study of dynamic behaviors, such as nonlinear effects, power evolution, and pulse evolution of light in fiber gain media, solving dynamic rate equations in fiber laser systems is involved, which is computationally intensive and directly affects overall computational efficiency. A modified
[...] Read more.
In the study of dynamic behaviors, such as nonlinear effects, power evolution, and pulse evolution of light in fiber gain media, solving dynamic rate equations in fiber laser systems is involved, which is computationally intensive and directly affects overall computational efficiency. A modified difference scheme is proposed to solve fiber dynamic rate equations efficiently. The advantages of the improved scheme and its convergence rate are analyzed. By incorporating a correction coefficient into the finite difference, the approximations of spatial and temporal derivatives are improved, greatly enhancing the performance of the numerical method. The computational results of the proposed method are compared with those of the conventional upwind difference scheme, demonstrating that the improved method is more stable and requires fewer sampling points to maintain a certain level of precision, thereby saving significant computation time and computational resources. The power and spectral evolutions of the fiber laser oscillator under different pump conditions are simulated and compared with experimental data, validating the applicability and reliability of the rapid solving method.
Full article
(This article belongs to the Special Issue High-Power Fiber Lasers)
Open AccessCommunication
Quality Assessment of Perovskite Solar Cells: An Industrial Point of View
by
Nicolò Lago, Francesco Moretti, Noah Tormena, Alessandro Caria, Matteo Buffolo, Carlo De Santi, Nicola Trivellin, Andrea Cester, Gaudenzio Meneghesso, Enrico Zanoni, Matteo Meneghini, Fabio Matteocci, Jessica Barichello, Luigi Vesce, Aldo Di Carlo and Federico Quartiani
Photonics 2024, 11(9), 880; https://doi.org/10.3390/photonics11090880 (registering DOI) - 19 Sep 2024
Abstract
The mass production of photovoltaic (PV) devices requires fast and reliable characterization methods and equipment. PV manufacturers produce a complete module roughly every 20 s, and the electrical performance assessment is typically completed in less than 1 s. Times are even more stringent
[...] Read more.
The mass production of photovoltaic (PV) devices requires fast and reliable characterization methods and equipment. PV manufacturers produce a complete module roughly every 20 s, and the electrical performance assessment is typically completed in less than 1 s. Times are even more stringent during cell manufacturing. To be competitive in the PV market, perovskite solar cells and modules aim to the same target, i.e., fast and reliable quality assessment. This communication report discusses the limit of characterizing the current perovskite technology. Standard current vs voltage measurements are compared to maximum power point tracking (MPPT), and a fast MPPT procedure is developed to meet the highly demand standard for quality control in the industry of PV production.
Full article
(This article belongs to the Special Issue Advances in Perovskite Solar Cells)
Open AccessCommunication
Improving the Performance of Bidirectional Communication System Using Second-Order Raman Amplifiers
by
Zhongshuai Feng, Peili He, Wei Li, Kaijing Hu, Fei Tong and Xingrui Su
Photonics 2024, 11(9), 879; https://doi.org/10.3390/photonics11090879 (registering DOI) - 19 Sep 2024
Abstract
In order to achieve low-cost scalability, the same-wavelength bidirectional (SWB) fiber communication system is a better solution. We present a detailed investigation of the performance of the different orders Raman amplifiers in same-wavelength bidirectional fiber communication systems. We discuss how to suppress the
[...] Read more.
In order to achieve low-cost scalability, the same-wavelength bidirectional (SWB) fiber communication system is a better solution. We present a detailed investigation of the performance of the different orders Raman amplifiers in same-wavelength bidirectional fiber communication systems. We discuss how to suppress the main factor affecting system performance which is Rayleigh scattering noise (RSN). By using different Raman amplifiers to construct different quasi-lossless transmission, the performance changes in the same-wavelength bidirectional fiber optic communication system were studied. On this basis, multi-channel and same-wavelength single fiber bidirectional system experiments were conducted to compare the performance of second-order Raman systems and first-order Raman systems. The results indicate that the Rayleigh scattering suppression effect of second-order Raman systems is better, and compared to first-order Raman systems, the average signal-to-noise ratio (SNR) can be increased by 2.88 dB.
Full article
(This article belongs to the Special Issue Advancements in Optical Sensing and Communication Technologies)
Open AccessArticle
Asymmetric Optical Scanning Holography Encryption with Elgamal Algorithm
by
Chunying Wu, Yinggang Ding, Aimin Yan, Ting-Chung Poon and Peter Wai Ming Tsang
Photonics 2024, 11(9), 878; https://doi.org/10.3390/photonics11090878 - 19 Sep 2024
Abstract
This paper proposes an asymmetric scanning holography cryptosystem based on the Elgamal algorithm. The method encodes images with sine and cosine holograms. Subsequently, each hologram is divided into a signed bit matrix and an unsigned hologram matrix, both encrypted using the sender’s private
[...] Read more.
This paper proposes an asymmetric scanning holography cryptosystem based on the Elgamal algorithm. The method encodes images with sine and cosine holograms. Subsequently, each hologram is divided into a signed bit matrix and an unsigned hologram matrix, both encrypted using the sender’s private key and the receiver’s public key. The resulting ciphertext matrices are then transmitted to the receiver. Upon receipt, the receiver decrypts the ciphertext matrices using their private key and the sender’s public key. We employ an asymmetric single-image encryption method for key management and dispatch for securing imaging and transmission. Furthermore, we conducted a sensitivity analysis of the encryption system. The image encryption metrics, including histograms of holograms, adjacent pixel correlation, image correlation, the peak signal-to-noise ratio, and the structural similarity index, were also examined. The results demonstrate the security and stability of the proposed method.
Full article
(This article belongs to the Special Issue Holographic Information Processing)
►▼
Show Figures
Figure 1
Open AccessArticle
Kilowatt-Level High-Efficiency Narrow-Linewidth All-Fiber Tm3+-Doped Laser
by
Hongyu Wang, Qilai Zhao, Hang Liu, Yuxin Sun, Jialong Li, Junjie Zheng, Ye Yuan, Qianwen Zhang, Changsheng Yang, Yujun Feng, Yinhong Sun, Zhongmin Yang and Shanhui Xu
Photonics 2024, 11(9), 877; https://doi.org/10.3390/photonics11090877 - 19 Sep 2024
Abstract
In this study, a kilowatt-level high-efficiency narrow-linewidth all-fiber Tm3+-doped continuous-wave laser operating at 1.95 μm is demonstrated. Benefitting from an advanced boost design of a two-stage main amplifier, it not only effectively manages heat dissipation resulting from the high pump-induced quantum
[...] Read more.
In this study, a kilowatt-level high-efficiency narrow-linewidth all-fiber Tm3+-doped continuous-wave laser operating at 1.95 μm is demonstrated. Benefitting from an advanced boost design of a two-stage main amplifier, it not only effectively manages heat dissipation resulting from the high pump-induced quantum defect but also realizes the controlled extraction of optical gain and improves the optical conversion efficiency. Finally, this laser system has realized an output power of 1018 W, a linewidth of 3.8 GHz, and a slope efficiency of 60.0% simultaneously. Moreover, a high optical signal-to-noise ratio of over 45 dB and excellent beam quality of M2 factors 1.19 are obtained. To the best of our knowledge, this represents the narrowest linewidth and highest slope efficiency achieved in a kilowatt-level Tm³⁺-doped fiber laser. Such a high-performance laser is ideally suited for mid-infrared generation and remote sensing applications.
Full article
(This article belongs to the Section Lasers, Light Sources and Sensors)
►▼
Show Figures
Figure 1
Open AccessArticle
The Correction Method for Wavefront Aberration Caused by Spectrum-Splitting Filters in Multi-Modal Optical Imaging System
by
Xiaolin Liu, Ying Huang, Xu Yan, Li Wang, Qiang Li, Tingcheng Zhang, Bin Hu, Wenping Lei, Shengbo Mu and Xiaohong Zhang
Photonics 2024, 11(9), 876; https://doi.org/10.3390/photonics11090876 - 19 Sep 2024
Abstract
In current biomedical and environmental detection, multi-modal optical imaging technology is playing an increasingly important role. By utilizing information from dimensions such as spectra and polarization, it reflects the detailed characteristics and material properties of the targets. However, as detection system performance becomes
[...] Read more.
In current biomedical and environmental detection, multi-modal optical imaging technology is playing an increasingly important role. By utilizing information from dimensions such as spectra and polarization, it reflects the detailed characteristics and material properties of the targets. However, as detection system performance becomes more complex, issues such as aberrations introduced by multilayered lenses, signal attenuation, decreased polarization sensitivity, and latency can no longer be ignored. These factors directly affect the assessment of image details, influencing subsequent analyses. In this paper, we propose a method for designing and optimizing spectrum-splitting filters that considers the wavefront aberration and transmittance of the multi-modal optical imaging system. The method of optimizing coating phases to minimize scalar phase aberrations while maximizing system transmission leads to substantially improved imaging performance. Simulation and experimental results demonstrate that the method can improve the imaging performance. The proposed approach has potential applications in fields such as biomedical field, multi-spectral, remote sensing and microscopy.
Full article
(This article belongs to the Special Issue Optical Technologies for Biomedical Science)
►▼
Show Figures
Figure 1
Open AccessArticle
Comparative Study on the Interest in Non-Uniform Rational B-Splines Representation versus Polynomial Surface Description in a Freeform Three-Mirror Anastigmat
by
Clément Freslier, Guillaume Druart, Alice Fontbonne, Thierry Lépine, Christophe Buisset, Tibor Agocs, Arnaud Heliere, Fanny Keller, Jean-Baptiste Volatier, Stéphane Beaussier and Paul Jougla
Photonics 2024, 11(9), 875; https://doi.org/10.3390/photonics11090875 - 18 Sep 2024
Abstract
Novel freeform optical design methods can be classified in two categories, depending on whether they focus on the generation of a starting point or the development of new optimization tools. In this paper, we design a freeform three-mirror anastigmat (TMA) and compare different
[...] Read more.
Novel freeform optical design methods can be classified in two categories, depending on whether they focus on the generation of a starting point or the development of new optimization tools. In this paper, we design a freeform three-mirror anastigmat (TMA) and compare different surface representations using either a differential ray tracer as a new optimization tool or a commercial ray tracer (ANSYS-ZEMAX OpticStudio). For differential ray tracing, we used FORMIDABLE (Freeform Optics Raytracer with Manufacturable Imaging Design cApaBiLitiEs), an optical design library with differential ray tracing and Non-Uniform Rational B-Splines (NURBS) optimization capabilities, available under the European Software Community License (ESCL). NURBS allow a freeform surface to be represented without needing any prior knowledge of the surface, such as the polynomial degree in polynomial descriptions. OpticStudio and other commercial optical design software are designed to optimize polynomial surfaces but are not well-suited to optimize NURBS surfaces, requiring a custom optical design library. In order to demonstrate the interest in using NURBS representation, we designed and independently optimized two freeform telescopes over different iteration cycles; with NURBS using FORMIDABLE or with XY polynomials using OpticStudio. We then compared the resulting systems using their root mean square field maps to assess the optimization quality of each surface representation. We also provided a full-system comparison, including mirror freeform departures. This study shows that NURBS can be a relevant alternative to XY polynomials for the freeform optimization of reflective three-mirror telescopes as it achieves more a uniform imaging quality in the field of view.
Full article
(This article belongs to the Special Issue New Advances in Freeform Optics Design)
►▼
Show Figures
Figure 1
Open AccessArticle
Accurate Inspection and Super-Resolution Reconstruction for Additive Manufactured Defects Based on Stokes Vector Method and Deep Learning
by
Shangrongxi Sun, Xing Peng and Hongbing Cao
Photonics 2024, 11(9), 874; https://doi.org/10.3390/photonics11090874 - 18 Sep 2024
Abstract
Defects in additive manufacturing processes are closely related to the mechanical and physical properties of the components. However, the extreme conditions of high temperatures, intense light, and powder during the manufacturing process present significant challenges for defect detection. Additionally, the high reflectivity of
[...] Read more.
Defects in additive manufacturing processes are closely related to the mechanical and physical properties of the components. However, the extreme conditions of high temperatures, intense light, and powder during the manufacturing process present significant challenges for defect detection. Additionally, the high reflectivity of metallic components can cause pixels in image sensors to become overexposed, resulting in the loss of many defect signals. Thus, this paper mainly focuses on proposing an accurate inspection and super-resolution reconstruction method for additive manufactured defects based on Stokes vector and deep learning, where the Stokes vectors, polarization degree, and polarization angles of the inspected defects are effectively utilized to suppress the high reflectivity of metallic surfaces, enhance the contrast of defect regions, and highlight the boundaries of defects. Furthermore, a modified SRGAN model designated SRGAN-H is presented by employing an additional convolutional layer and activation functions, including Harswish and Tanh, to accelerate the convergence of the SRGAN-H network and improve the reconstruction of the additive manufactured defect region. The experiment results demonstrated that the SRGAN-H model outperformed SRGAN and traditional SR reconstruction algorithms in terms of the images of Stokes vectors, polarization degree, and polarization angles. For the scratch and hole test sets, the PSNR values were 33.405 and 31.159, respectively, and the SSIM values were 0.890 and 0.896, respectively. These results reflect the effectiveness of the SRGAN-H model in super-resolution reconstruction of scratch and hole images. For the scratch and hole images chosen in this study, the PSNR values of SRGAN-H for single image super-resolution reconstruction ranged from 31.86786 to 43.82374, higher than the results obtained by the pre-improvement SRGAN algorithm.
Full article
(This article belongs to the Special Issue New Perspectives in Optical Design)
►▼
Show Figures
Figure 1
Open AccessReview
A Comprehensive Exploration of Contemporary Photonic Devices in Space Exploration: A Review
by
Muhammad A. Butt
Photonics 2024, 11(9), 873; https://doi.org/10.3390/photonics11090873 - 18 Sep 2024
Abstract
Photonics plays a pivotal role in propelling space exploration forward, providing innovative solutions to address the challenges presented by the unforgiving and expansive realm of outer space. Photonic-based devices, encompassing technologies such as lasers, optical fibers, and photodetectors, are instrumental in various aspects
[...] Read more.
Photonics plays a pivotal role in propelling space exploration forward, providing innovative solutions to address the challenges presented by the unforgiving and expansive realm of outer space. Photonic-based devices, encompassing technologies such as lasers, optical fibers, and photodetectors, are instrumental in various aspects of space missions. A notable application is in communication systems, where optical communication facilitates high-speed data transfer, ensuring efficient transmission of information across vast interplanetary distances. This comprehensive review unveils a selection of the most extensively employed photonic devices within the realm of space exploration.
Full article
(This article belongs to the Special Issue Innovations in Optical Wireless Communications: Challenges and Opportunities)
►▼
Show Figures
Figure 1
Open AccessReview
Advances in Photoacoustic Endoscopic Imaging Technology for Prostate Cancer Detection
by
Ningning Wei, Huiting Chen, Bin Li, Xiaojun Dong and Bo Wang
Photonics 2024, 11(9), 872; https://doi.org/10.3390/photonics11090872 - 18 Sep 2024
Abstract
The rapid progress in biomedical imaging technology has generated considerable interest in new non-invasive photoacoustic endoscopy imaging techniques. This emerging technology offers significant benefits, including high spectral specificity, strong tissue penetration, and real-time multidimensional high-resolution imaging capabilities, which enhance clinical diagnosis and treatment
[...] Read more.
The rapid progress in biomedical imaging technology has generated considerable interest in new non-invasive photoacoustic endoscopy imaging techniques. This emerging technology offers significant benefits, including high spectral specificity, strong tissue penetration, and real-time multidimensional high-resolution imaging capabilities, which enhance clinical diagnosis and treatment of prostate cancer. This paper delivers a thorough review of current prostate cancer screening techniques, the core principles of photoacoustic endoscopy imaging, and the latest research on its use in detecting prostate cancer. Additionally, the limitations of this technology in prostate cancer detection are discussed, and future development trends are anticipated.
Full article
(This article belongs to the Special Issue New Perspectives in Biomedical Optics and Optical Imaging)
►▼
Show Figures
Figure 1
Open AccessReview
Photonic Angular Momentum in Intense Light–Matter Interactions
by
Alex Schimmoller, Spencer Walker and Alexandra S. Landsman
Photonics 2024, 11(9), 871; https://doi.org/10.3390/photonics11090871 - 17 Sep 2024
Abstract
Light contains both spin and orbital angular momentum. Despite contributing equally to the total photonic angular momentum, these components derive from quite different parts of the electromagnetic field profile, namely its polarization and spatial variation, respectively, and therefore do not always share equal
[...] Read more.
Light contains both spin and orbital angular momentum. Despite contributing equally to the total photonic angular momentum, these components derive from quite different parts of the electromagnetic field profile, namely its polarization and spatial variation, respectively, and therefore do not always share equal influence in light–matter interactions. With the growing interest in utilizing light’s orbital angular momentum to practice added control in the study of atomic systems, it becomes increasingly important for students and researchers to understand the subtlety involved in these interactions. In this article, we present a review of the fundamental concepts and recent experiments related to the interaction of beams containing orbital angular momentum with atoms. An emphasis is placed on understanding light’s angular momentum from the perspective of both classical waves and individual photons. We then review the application of these beams in recent experiments, namely single- and few-photon transitions, strong-field ionization, and high-harmonic generation, highlighting the role of light’s orbital angular momentum and the atom’s location within the beam profile within each case.
Full article
(This article belongs to the Special Issue Optical Vortex: Fundamentals and Applications)
►▼
Show Figures
Figure 1
Open AccessArticle
Second-Order Microring Filter with Large Free-Spectral-Range and Wavelength-Tunable-Range over 50 nm
by
Jiamei Gu, Shuojian Zhang, Qiongchan Shao, Mingyu Li, Xiao Ma and Jian-Jun He
Photonics 2024, 11(9), 870; https://doi.org/10.3390/photonics11090870 - 16 Sep 2024
Abstract
The high-order microring filter has been proposed for a larger free spectral range (FSR) compared with the single microring filter; therefore, it has great potential to be used in wavelength division multiplexing (WDM) systems. In this article, we have designed and fabricated a
[...] Read more.
The high-order microring filter has been proposed for a larger free spectral range (FSR) compared with the single microring filter; therefore, it has great potential to be used in wavelength division multiplexing (WDM) systems. In this article, we have designed and fabricated a second-order microring filter made up of two rings connected in series with two Ti thermal heaters deposited above them. The large FSR of 56.8 nm is obtained by decreasing the difference of the radii between the two series rings, achieving similar FSRs to that of higher-order filters but with a simpler and more compact design. The average electrical tuning efficiencies of the two heaters are 0.186 nm/mW and 0.207 nm/mW, and the center wavelength of the filter can be tuned over the entire FSR with an applied electrical power of less than 40 mW.
Full article
(This article belongs to the Special Issue Silicon-Based Integrated Optics: From Design to Applications)
►▼
Show Figures
Figure 1
Open AccessArticle
Analysis of the Temperature Field Characteristics and Thermal-Induced Errors of Miniature Interferometric Fiber Optic Gyroscopes in a Vacuum Environment
by
Zicheng Wang, Xiuwei Xia, Wei Gao and Xiangjun Zhang
Photonics 2024, 11(9), 869; https://doi.org/10.3390/photonics11090869 - 16 Sep 2024
Abstract
This paper investigates the mechanism of thermal-induced errors in interferometric fiber optic gyroscopes (IFOGs) caused by temperature changes in a vacuum environment, proposing a method for calculating thermal-induced errors in small fiber coils. Firstly, based on the Shupe effect and the thermal stress
[...] Read more.
This paper investigates the mechanism of thermal-induced errors in interferometric fiber optic gyroscopes (IFOGs) caused by temperature changes in a vacuum environment, proposing a method for calculating thermal-induced errors in small fiber coils. Firstly, based on the Shupe effect and the thermal stress caused by temperature changes around the fiber coil, a three-dimensional thermal-induced error model for small fiber coils is established. Secondly, a spatial fiber optic inertial measurement unit (IMU) model is designed using the Creo 3D modeling software (creo 7.0.0). The model is then imported into the Ansys finite element simulation software (ANSYS Workbench 15.0), where a temperature field is applied to the IMU based on actual temperature profiles to obtain the temperature distribution of the fiber coil at different times in a vacuum state. These data are then used in the three-dimensional thermal-induced error model to calculate the thermal-induced error of the FOG. Finally, a thermal vacuum experimental platform is set up to collect temperature variation data from the inertial measurement components. The experimental data are compared with the three-dimensional error model proposed in this paper as well as traditional error models. The root mean square error is approximately 33% lower than that of traditional error calculation methods, which also proves the theoretical accuracy.
Full article
(This article belongs to the Special Issue Advances in Optical Fiber Sensing Technology)
►▼
Show Figures
Figure 1
Open AccessArticle
A Modified Current-Mode VCSEL Driver for Short-Range LiDAR Sensor Applications in 180 nm CMOS
by
Juntong Li, Yeojin Chon, Shinhae Choi and Sung-Min Park
Photonics 2024, 11(9), 868; https://doi.org/10.3390/photonics11090868 - 16 Sep 2024
Abstract
This paper presents a modified current-mode vertical-cavity surface-emitting laser (VCSEL) driver as a transmitter for short-range light detection and ranging (LiDAR) sensors, where a stable bias generator is suggested with a regulated cascode current mirror circuit to provide the bias current of 1
[...] Read more.
This paper presents a modified current-mode vertical-cavity surface-emitting laser (VCSEL) driver as a transmitter for short-range light detection and ranging (LiDAR) sensors, where a stable bias generator is suggested with a regulated cascode current mirror circuit to provide the bias current of 1 mA with a trivial deviation of 5.4%, even at the worst-case process–voltage–temperature (PVT) variations. Also, a modified current-steering logic circuit is exploited with N-type MOSFET (NMOS) switches to deliver the modulation currents of 0.1~10 mApp to the VCSEL diode simultaneously, with no overshoot distortions. Post-layout simulations of the modified current-mode VCSEL driver (m-CMVD), using 180 nm CMOS technology, demonstrate very large and clean output pulses with significantly reduced signal distortions. Hereby, the VCSEL diode is transformed into an equivalent circuit with a 1.6 V DC voltage and a 50 Ω resistor for circuit simulations. The proposed m-CMVD consumes a maximum of 11 mW from a 3.3 V supply voltage and the chip core occupies an area of 0.196 mm2.
Full article
(This article belongs to the Special Issue Semiconductor Lasers: Innovations, Challenges, and Future Perspectives)
►▼
Show Figures
Figure 1
Open AccessArticle
Enhanced Three-Axis Frame and Wand-Based Multi-Camera Calibration Method Using Adaptive Iteratively Reweighted Least Squares and Comprehensive Error Integration
by
Oleksandr Yuhai, Yubin Cho, Ahnryul Choi and Joung Hwan Mun
Photonics 2024, 11(9), 867; https://doi.org/10.3390/photonics11090867 - 15 Sep 2024
Abstract
The accurate transformation of multi-camera 2D coordinates into 3D coordinates is critical for applications like animation, gaming, and medical rehabilitation. This study unveils an enhanced multi-camera calibration method that alleviates the shortcomings of existing approaches by incorporating a comprehensive cost function and Adaptive
[...] Read more.
The accurate transformation of multi-camera 2D coordinates into 3D coordinates is critical for applications like animation, gaming, and medical rehabilitation. This study unveils an enhanced multi-camera calibration method that alleviates the shortcomings of existing approaches by incorporating a comprehensive cost function and Adaptive Iteratively Reweighted Least Squares (AIRLS) optimization. By integrating static error components (3D coordinate, distance, angle, and reprojection errors) with dynamic wand distance errors, the proposed comprehensive cost function facilitates precise multi-camera parameter calculations. The AIRLS optimization effectively balances the optimization of both static and dynamic error elements, enhancing the calibration’s robustness and efficiency. Comparative validation against advanced multi-camera calibration methods shows this method’s superior accuracy (average error 0.27 ± 0.22 mm) and robustness. Evaluation metrics including average distance error, standard deviation, and range (minimum and maximum) of errors, complemented by statistical analysis using ANOVA and post-hoc tests, underscore its efficacy. The method markedly enhances the accuracy of calculating intrinsic, extrinsic, and distortion parameters, proving highly effective for precise 3D reconstruction in diverse applications. This study represents substantial progression in multi-camera calibration, offering a dependable and efficient solution for intricate calibration challenges.
Full article
(This article belongs to the Special Issue Recent Advances in 3D Optical Measurement)
►▼
Show Figures
Figure 1
Open AccessArticle
Hunting for Monolayer Black Phosphorus with Photoluminescence Microscopy
by
Chenghao Pan, Yixuan Ma, Quan Wan, Boyang Yu, Shenyang Huang and Hugen Yan
Photonics 2024, 11(9), 866; https://doi.org/10.3390/photonics11090866 - 14 Sep 2024
Abstract
Monolayer black phosphorus (BP) holds great promise for naturally hyperbolic polaritons and correlated states in rectangular moiré superlattices. However, preparing and identifying high-quality monolayer BP are challenging due to its instability and high transparency, which limits extensive studies. In this study, we developed
[...] Read more.
Monolayer black phosphorus (BP) holds great promise for naturally hyperbolic polaritons and correlated states in rectangular moiré superlattices. However, preparing and identifying high-quality monolayer BP are challenging due to its instability and high transparency, which limits extensive studies. In this study, we developed a method for rapidly and nondestructively identifying monolayer BP and its crystal orientation simultaneously using modified photoluminescence (PL) microscopy. The optical contrast of monolayer BP has been significantly increased by at least twenty times compared to previous reports, making it visible even on a transparent substrate. The polarization dependence of optical contrast also allows for the in situ determination of crystal orientation. Our study facilitates the identification of monolayer BP, expediting more extensive research on and potential industrial applications of this material.
Full article
(This article belongs to the Special Issue Recent Advances in Infrared Photodetection and Imaging)
Open AccessArticle
In-Vivo Dosimetry for Ultra-High Dose Rate (UHDR) Electron Beam FLASH Radiotherapy Using an Organic (Plastic), an Organic–Inorganic Hybrid and an Inorganic Point Scintillator System
by
Verdi Vanreusel, Hugo Vallet, Jordi Wijnen, Benjamin Côté, Paul Leblans, Paul Sterckx, Dirk Vandenbroucke, Dirk Verellen and Luana de Freitas Nascimento
Photonics 2024, 11(9), 865; https://doi.org/10.3390/photonics11090865 - 13 Sep 2024
Abstract
Dosimetry is crucial in radiotherapy to warrant safe and correct treatment. In FLASH radiotherapy, where ultra-high dose rates (UHDRs) are used, the dosimetric demands are more stringent, requiring the development and investigation of new dosemeters. In this study, three prototype fiber-optic dosemeters (FODs)—an
[...] Read more.
Dosimetry is crucial in radiotherapy to warrant safe and correct treatment. In FLASH radiotherapy, where ultra-high dose rates (UHDRs) are used, the dosimetric demands are more stringent, requiring the development and investigation of new dosemeters. In this study, three prototype fiber-optic dosemeters (FODs)—an inorganic, an organic–inorganic hybrid metal halide, and an organic (plastic) scintillator are optimized and investigated for UHDR electron irradiations. The plastic FOD is developed by Medscint, whereas the others are in-house made. The stem signal is minimized by spectral decomposition for the plastic scintillator, and by band-pass wavelength filters for the inorganic and organic–inorganic hybrid metal halide FOD. All prototypes are tested for the dose rate defining parameters. The optimal band-pass wavelength filters are found to be centered around 500 nm and 425 nm for the inorganic and organic–inorganic hybrid metal halide FODs, respectively. A sampling frequency of 1000 Hz is chosen for the inorganic and organic–inorganic hybrid metal halide FODs. The plastic FOD shows to be the least dose rate dependent with maximum deviations of 3% from the reference for the relevant beam settings. The inorganic and organic–inorganic hybrid metal halide FODs, in contrast, show large deviations of >10% from the reference and require more investigation. The current FOD prototypes are insufficient for application in UHDR electron beams, and require further development and investigation.
Full article
(This article belongs to the Special Issue Optical Fibre Sensing: Recent Advances and Future Perspectives)
►▼
Show Figures
Figure 1
Open AccessReview
Advances in High-Efficiency Blue OLED Materials
by
Xiaoxue Yang, Ge Mu, Kangkang Weng and Xin Tang
Photonics 2024, 11(9), 864; https://doi.org/10.3390/photonics11090864 - 13 Sep 2024
Abstract
Organic light-emitting diode (OLED) technology has rapidly emerged in the display and lighting sectors due to its high contrast ratio, wide viewing angle, and sleek design. Beyond these attributes, OLEDs have also demonstrated crucial applications in medicine, fashion, sports, and more, leveraging their
[...] Read more.
Organic light-emitting diode (OLED) technology has rapidly emerged in the display and lighting sectors due to its high contrast ratio, wide viewing angle, and sleek design. Beyond these attributes, OLEDs have also demonstrated crucial applications in medicine, fashion, sports, and more, leveraging their emissive properties and flexible design. As the cornerstone of full-color displays, blue OLEDs, whose performance directly impacts color rendition and saturation, have garnered significant attention from both scientific researchers and industrial practitioners. Despite the numerous advantages of OLED technology, blue OLEDs still confront formidable challenges in terms of luminous efficiency, durability, and material stability. This review examines the evolution of blue OLED materials over recent years, specifically focusing on three generations: fluorescent, phosphorescent, and thermally activated delayed fluorescence (TADF). Through molecular design, device structure optimization, and the application of innovative technologies, remarkable advancements have been achieved in enhancing the luminous efficiency, lifetime, and color purity of blue OLEDs. However, to advance commercialization, future efforts must not only ensure high efficiency and long lifetime but also improve material stability, environmental sustainability, and reduce development costs. Emerging materials such as thermally activated exciton materials and the application of hyperfluorescent (HF) OLED technology represent vital driving forces for the continuous advancement of blue OLED technology. It is anticipated that significant milestones will continue to be achieved in the development of highly efficient blue OLEDs in the future.
Full article
(This article belongs to the Special Issue Organic Photodetectors, Displays, and Upconverters)
►▼
Show Figures
Figure 1
Open AccessCommunication
Ultra-Wideband Cross-Polarization Converter Using Metasurface Operating in the X- and K-Band
by
Muhammad Basir Abbas, Faizan Raza, Muhammad Abuzar Baqir, Olcay Altintas, Musarat Abbas, Muharrem KaraaSlan and Qaisar Abbas Naqvi
Photonics 2024, 11(9), 863; https://doi.org/10.3390/photonics11090863 - 12 Sep 2024
Abstract
The ultra-wideband polarization converters have been of interest to researcher due to their demand in satellite communication and navigation systems. This paper presents an ultra-wideband reflective cross-polarization converter comprising a stair-shaped metasurface. By observation, the alleged structure allows the conversion of linearly polarized
[...] Read more.
The ultra-wideband polarization converters have been of interest to researcher due to their demand in satellite communication and navigation systems. This paper presents an ultra-wideband reflective cross-polarization converter comprising a stair-shaped metasurface. By observation, the alleged structure allows the conversion of linearly polarized waves to orthogonal components, having a polarization conversion ratio of greater than 90% spread across the large frequency range of 12.94 to 16.54 GHz and 17.54 to 26 GHz. A highly efficient, ultra-high frequency polarization conversion is achieved by the utilization of strong electromagnetic resonance coupling between the upper and lower layers of the metasurface. Further, it is depicted that the polarization converter has a wide obliquity of incidence wave. Moreover, the simulation and measured results show a good match. The linear polarization converter is simple in design but is of high performance, and therefore, might be useful in satellite communication, imaging systems, and navigation systems.
Full article
(This article belongs to the Special Issue Nonlinear Optical Phenomena in Rare Earth Doped Crystals)
►▼
Show Figures
Figure 1
Open AccessArticle
Double-Pulse Laser Fragmentation/Laser-Induced Fluorescence Method for Remote Detection of Traces of Trinitrotoluene
by
Sergei Bobrovnikov, Evgeny Gorlov and Viktor Zharkov
Photonics 2024, 11(9), 862; https://doi.org/10.3390/photonics11090862 - 12 Sep 2024
Abstract
This paper presents the results of an experimental study of the dynamic characteristics of the process of laser fragmentation/laser-induced fluorescence (LF/LIF) of trinitrotoluene traces on a paper surface under synchronized double-pulse laser irradiation. An Nd:YAG-laser (266 nm) was used for the fragmentation of
[...] Read more.
This paper presents the results of an experimental study of the dynamic characteristics of the process of laser fragmentation/laser-induced fluorescence (LF/LIF) of trinitrotoluene traces on a paper surface under synchronized double-pulse laser irradiation. An Nd:YAG-laser (266 nm) was used for the fragmentation of TNT molecules, while fluorescence excitation of their NO fragments was performed using a KrF laser with a generation line of 247.867 nm in the region of the location of the bandhead of the P12 branch of the γ(0, 2) absorption band of the NO molecule. It was shown that the dissociation process of TNT traces has an inertial character and continues after the cessation of the fragmenting laser pulse. It was found that with the delay values between the fragmenting and probing laser pulses in the region of 200 ns, the efficiency of the LF/LIF method can be increased by 12 times. This paper presents the results of an experimental evaluation of the efficiency of two-pulse LF/LIF compared to single-pulse laser exposure, where the fragmentation of TNT molecules and excitation of their NO fragments were simultaneously performed by KrF laser pulses. The possibility of multiple increases in the efficiency of two-pulse LF/LIF with an increase in the energy density of the fragmenting laser radiation was shown. The obtained results are important in terms of increasing the sensitivity and/or range of the LF/LIF method for remote detection of traces of nitrocompounds.
Full article
(This article belongs to the Section Lasers, Light Sources and Sensors)
►▼
Show Figures
Figure 1
Journal Menu
► ▼ Journal Menu-
- Photonics Home
- Aims & Scope
- Editorial Board
- Reviewer Board
- Topical Advisory Panel
- Instructions for Authors
- Special Issues
- Topics
- Sections
- Article Processing Charge
- Indexing & Archiving
- Editor’s Choice Articles
- Most Cited & Viewed
- Journal Statistics
- Journal History
- Journal Awards
- Conferences
- Editorial Office
- 10th Anniversary
Journal Browser
► ▼ Journal BrowserHighly Accessed Articles
Latest Books
E-Mail Alert
News
Topics
Topic in
Applied Sciences, Electronics, Optics, Photonics, Technologies
The Extended Technological Platform Based on Optics and Microwaves: Conventional and Hybrid Solutions
Topic Editors: Francesco Prudenzano, Antonella D’Orazio, Maurizio FerrariDeadline: 30 September 2024
Topic in
Automation, Biosensors, Fibers, Photonics, Sensors
Advance and Applications of Fiber Optic Measurement: 2nd Edition
Topic Editors: Flavio Esposito, Stefania Campopiano, Agostino IadiciccoDeadline: 30 November 2024
Topic in
Chemistry, Materials, Micromachines, Molecules, Photonics
Materials, Structure Designs and Device Fabrications for Highly Efficient/Long Lifetime Organic Light-Emitting Diodes
Topic Editors: Ping Chen, Jwo-Huei JouDeadline: 31 December 2024
Topic in
Crystals, Nanomaterials, Micromachines, Coatings, Materials, Photonics
Laser-Induced Damage Properties of Optical Materials
Topic Editors: Laixi Sun, Yafei Lian, Jin Huang, Hongjie LiuDeadline: 31 March 2025
Conferences
Special Issues
Special Issue in
Photonics
Single Frequency Fiber Lasers and Their Applications
Guest Editors: Ting Feng, Guolu Yin, Wanjing Peng, Bin YinDeadline: 20 September 2024
Special Issue in
Photonics
Progress and Prospects in Optical Fiber Sensing
Guest Editor: Xiangge HeDeadline: 20 September 2024
Special Issue in
Photonics
Photon-Photon Collision Using Extreme Lasers
Guest Editor: Luis RosoDeadline: 20 September 2024
Special Issue in
Photonics
Applications of Single-Photon Detector
Guest Editors: Yi-Shan Lee, Jau-Yang WuDeadline: 20 September 2024