Two bifunctional nanophosphors of BaLaAl3O7:xTb3+ (BLAO:Tb) and BaYAl3O7: yTb3+ (BYAO:Tb) have been designed and prepared by the high-temperature solid state reaction method. The green photoluminescence (PL) of the BYAO:Tb sample is significantly stronger than that of the BLAO:Tb sample. The optimal Tb3+ doping concentrations of two systems are 4 and 5 mol%, respectively. In addition, the BLAO:Tb and

Monitoring the polarization signature of the sky is valuable for navigation, meteorology, and remote sensing. However, the neutral points—Babinet (above the Sun), Brewster (below the Sun), Arago (above the anti-Sun), and the Fourth (below the anti-Sun)—remain underutilized as meteorological tools. The neutral points are formed through multiple scattering, making them useful markers for atmospheric

Given the challenges faced by object detection methods that rely on visible light in complex environments, many researchers have begun to explore the combination of infrared and visible imaging for multi-modal detection. Existing results show that multi-modal fusion has proven effective for improving object detection outcomes. However, most current multi-modal detection methods rely on fixed-parameter

In this paper, we investigate and analyze the optical unidirectional transmission based on a tapered fiber-based asymmetric Sagnac interferometer. By carefully designing the asymmetric structure, there are the different coupling conditions and different intensities of multi-mode interferences in the Sagnac loop when the light enters from the different input ports. The maximal difference of the transmission

Spherical markers are important in near-infrared (NIR) locators of orthopedic surgical robots. The spherical markers suffer from poor occlusion resistance due to occlusion by medical staff or blood contamination. Solutions to this challenge, such as adding markers or cameras, are limited by space and system complexity in the surgical environment. Compared with spherical markers, planar markers have

The holographic Maxwellian display, as a promising technique, offers a potential solution to the vergence–accommodation conflict in see-through near-eye displays for augmented reality applications. However, traditional holographic Maxwellian displays primarily rely on iterative or non-iterative algorithms, which face the challenge of balancing image quality and computational efficiency. To address

This project presents the design and fabrication of a polarization-independent liquid crystal-on-a-silicon (PI-LCoS) phase modulator that utilizes a polymer quarter-wave plate (QWP) for polarization conversion. The device features a novel silicon backplane including DRAM-based analog pixel circuit with fine grayscale control, and small pixel size, achievable using standard foundry processes. We demonstrate

This paper presents a new method for analyzing ghost paths for camera lens design using a method that predefines ray orders and uses cloud-based parallel processing. Our method enables comprehensive ghost analysis of complex optical systems with multiple reflections, which were previously considered computationally impractical. The performance evaluation demonstrated the successful processing of over

To enhance chaotic complexity and conceal time-delay signatures, we propose an optically chaotic secure communication system. The system combines chaotic intensity signals from an amplified spontaneous emission (ASE) noise source with an electro-optical phase delay oscillating feedback loop through optical injection. It integrates all-optical intensity chaos and electro-optical feedback to produce

This study proposes a solid-state device that can be updated to high-response spatial light modulators. We demonstrate an electro-optic grating device based on the Kerr effect in potassium tantalate niobate (KTN) crystals that exhibit a relative dielectric constant exceeding 10,000. The time response in spatial light modulation can be enhanced by a quadratic electro-optic material with high permittivity

A bundle of digitally directed beams, capable of instantaneously controlling their direction at every point within a field of view, is proposed for the inspection of microscale defects in manufacturing processes.

A rigorous treatment of the reflection and transmission of an electromagnetic wave by a superconductor in its ground state is reported. Starting from Maxwell’s equations, a calculation on the reflection and refraction at the interface between a metallic and superconducting plate is made. For the metal, a complex conductivity \(\sigma ^{\textrm{Re}} + i\sigma ^{\textrm{Im}}\) derived from the Drude-Zener

In this paper, an all-dielectric metasurface refractive index sensor based on Fano resonance is proposed. The unit structure consists of two silicon ellipsoidal columns with rectangular holes deposited on a silicon dioxide substrate. Based on the theory of bound states in the continuum (BIC), the transition from BIC to quasi-bound states in the continuum (QBIC) can be achieved by modifying the tilting

We investigate the photoelectron momentum distributions (PEMDs) of hydrogen atoms ionized by a parallel two-color chirped laser field, employing the semi-classical two-step model (SCTS). By modulating the chirp parameter and adjusting the ionization time offset on the attosecond timescale, we demonstrate the ability to control electronic interference across different orbitals. We present PEMDs images

Infrared sensors are widely used in human action recognition because of their low light influence and excellent privacy protection. However, the traditional deep learning networks and training or testing methods tend to fall into the trap of local optimum because of the similarity between infrared image classes and the lack of discriminative features such as texture and depth, and thus obtain poor

Turbulence effect is an important factor leading to performance degradation of underwater wireless optical communication (UWOC) systems. In order to improve the reliability of the communication system, this paper adopts a UWOC system based on low-density parity-check (LDPC) code and pulse position modulation (PPM) to overcome the effects caused by turbulence, and proposes an improved Offset Min-Sum

Injection-molded lenses have an inhomogeneous stress-induced birefringence that can degrade optical performance. This paper presents a new approach for measuring and analyzing inhomogeneous anisotropic samples. The birefringence distribution is characterized by 3D index ellipsoids, and a tomographic reconstruction of this 3D distribution is developed from a linear line projection relationship between

In this study, we present a through-focus re-radiation simulation aimed at detecting scattering from semiconductor structures. We employ the beam synthesis propagation (BSP) module within the finite-difference time-domain (FDTD) method, optimizing the simulation of optical systems by reducing time and computational resources typically required for imaging and illumination. To validate the approach

In this paper, we report the theory of a self-coupling laser sensor array system for improving the signal-frequency inversion problem and the results of velocity measurements with this system. A self-coupling laser sensor is an interferometer that uses optical beats produced by the interference between the light returned from the laser target and the light in the active layer of the laser diode. Using

The demand for fast, accurate, and cost-effective methods for three-dimensional shape and color measurements has been increasing. Ideally, both the shape and color of an object should be obtained in a single shot. Color fringe projection profilometry allows single-shot 3D shape measurement; however, it faces challenges when applied to colored objects. The fringe patterns are attenuated, leading to

In various sports, the motion information of athletes is often measured for monitoring and evaluation, and the direct use of common optical equipment to determine the position and orientation of moving objects according to geometric information in a scene has become an important research topic in image understanding. As many sports grounds have a center circle and halfway line, we propose an algorithm

This study investigates the entanglement and squeezing characteristics of light generated by a non-degenerate, coherently driven three-level laser in an open cavity, coupled to a two-mode vacuum reservoir through a single-port mirror. By normal ordering the noise operators, we simplified the calculations and derived the evolution equations for the atomic operators using the master equation. From the

A novel self-powered ultraviolet (UV) photodetector (PD) based on a CuI/MgZnO heterojunction modified by an ultrathin Cu2O layer has been fabricated by the successive ionic layer adsorption and reaction (SILAR) method. Compared with the CuI/MgZnO self-powered PD, the optimised heterojunction PD (CuI/Cu2O/MgZnO) exhibits significantly improved self-powered properties. Under 325 nm UV light at an intensity

In the industrial production of steel materials, various complex defects may appear on the steel surface owing to the influence of environmental and other ambient factors. These defects are often accompanied by large amounts of background texture information. Especially, some defects with the low resolution and small size are prone to false alarms and missing detections. Aiming to address the issues

Background Two-dimensional mapping based on reflectance measurements is a promising approach for evaluating the characteristics of breast cancer and its response to chemotherapy. However, three-dimensional imaging should enable extraction of more accurate values and distributions of the parameters, potentially increasing the validity of the assessment. Therefore, we have been developing reflectance

With the development of deep learning and structured light streak projection techniques in three-dimensional (3D) imaging, research on the direct reconstruction of 3D shapes from single-streak images has attracted much attention. However, accurately reconstructing 3D shapes is particularly challenging when dealing with objects with specular reflective surfaces. To address this problem, this paper proposes

A microchannel plates (MCPs) photon-counting detector with a cross-delay line (XDL) is expected for high-quality and wide-field target imaging. However, it is a great challenge for the uniformity of system response as the increasing of effective detection area. In this article, we develop a XDL photon-counting detector with a wide field of 120 mm × 50 mm. Additionally, we investigate the origin of

Novel hexagonal form factor for evaluating chromaticity distribution of color speckle using red, green, and blue lasers is proposed. The measured color speckle distribution data were plotted on CIE 1931 chromaticity diagram. Only the small amount of outer rim data was extracted from the whole data of the chromaticity distribution to introduce the novel form factor. Specifically, the highest 1% and

3D displays sometimes evoke illusion of perceived rotation angle change. In hollow face illusion, the direction of the 3D face changes according to the observation angle although the 3D face itself is static. Arc 3D display can show simple 3D image that is visible over a wide viewing angle by use of a thin substrate and illumination light. This structure is suitable for various applications such as

A simple photonic crystal fiber (PCF) arranged in a square geometry with two gold-coated air holes and one material-infiltrated core is proposed. A broadband polarization filter and a temperature sensor can be achieved based on the same simple PCF structure, with a hollow core separately filled with liquid crystal and toluene. The polarization filtering and sensing properties of the proposed PCF were

Mid-air imaging, a visual display technology for augmented reality (AR) that enables multiple people to view images simultaneously without the need for special eyewear, involves the formation of real images in mid-air through various optical elements. This paper presents a novel mid-air imaging optical plate, termed the truncated cylindrical array plate (TCAP). TCAP is composed of transparent cylinders

Electro-optic (EO) modulators are crucial components to generate high-speed photonic signals in the modern photonic communication system. Here we study the performance of a hybrid EO modulator employing a Si slot waveguide and a BaTiO3 layer, where the EO effect of BaTiO3 is stronger than that of widely used LiNbO\(_3\). We demonstrate that an appropriate design for the slot waveguide, the BaTiO\(_3\)

This paper proposes a novel pixel shift-based dual-phase modulation method (PS-DPMM) designed to enhance the spatial resolution of complex amplitude modulations. Conventional techniques, including off-axis computer-generated holograms (CGH), double-phase holograms (DPH), and kinoforms, often encounter issues like low diffraction efficiency, limited spatial resolution, and high speckle noise. Although

Multiplication is a fundamental operation in computer systems but is often constrained by the carry-delay inherent to conventional addition methods. Ternary optical computing offers an efficient solution, leveraging its advantages such as large data capacity, reconfigurable processing, and MSD adder without carry-delay. This study introduces and develops a modified signed digit (MSD) multiplication

In surveillance camera systems and other human-image analysis systems, it is important to measure human shapes with high resolution. However, the spatial resolution and image quality achievable through approaches based solely on optical design and image processing are fundamentally limited by hardware constraints and the inherent difficulty of the inverse problems involved. To overcome these limitations

A simple-structured total internal reflection terahertz filter based on a microstructured optical fiber is proposed in this paper, consisting of two non-uniform thickness dielectric tubes symmetrically nested within an outer cladding. The investigation uses the finite element method and the simulation results show that the x-polarized fundamental mode (XPFM) is well confined within the fiber core,

In this paper, a switchable multi-wavelength fiber laser mode locked by molybdenum disulfide (MoS2) film wrapped microfiber is demonstrated. By tuning intra-cavity loss and linear birefringence, switchable single-, double-, and triple-wavelength conventional solitons (CSs) are formed. Additionally, quadruple-wavelength solitons with center wavelengths of 1528 nm, 1532 nm, 1552 nm, and 1562 nm are realized

Underwater images often suffer from color shift and visual blur due to light absorption and scattering in the water medium. An adaptive image enhancement method is proposed for underwater image quality improvement. First, adaptive color compensation is proposed based on the color features of the image, and selectively apply the gray world assumption according to the degree of color unevenness. Second

The formation of thrombus in blood may be a cause of thrombosis which induces symptoms, such as myocardial infarction, cerebral infarction, and economy class syndrome. Recently, investigations on blood flows inside artificial blood vessel and artificial organ have been performed energetically for clinical application. Thus, in vitro monitoring of thrombogenesis in blood flow inside them is thought

Heat-assisted magnetic recording (HAMR) is a promising technology for improving the recording density of hard disk drives. A near-field transducer (NFT), which forms a small light spot on a recording medium, is necessary in HAMR. The authors’ group previously proposed a novel device, in which a metal nano-antenna acting as an NFT is attached to a semiconductor ring resonator acting as a light source

Nonlinear photoacoustic-based methods for measuring high-speed blood flow velocity typically use a single-pulse laser or a dual-pulse laser system with high repetition rate to achieve thermal tagging and acoustic excitation at the same time. However, the peak power of the pulsed laser is too high and can easily exceed the damage threshold, causing the blood to be overheated, which limits the application

An aerial 3D image formed by the use of a 3D-shaped light source gives a greater sense of reality compared to the conventional aerial 2D image. In particular, an aerial image of hollow face evokes a kind of illusion that the direction of the face changes depending on the viewing direction. In this study, we investigate the viewing zone of an aerial 3D display that employs a 3D object as a light source

Optical interconnection technology is the most promising solution for on-chip multi-core interconnection because of its advantages over electrical interconnection. To improve the performance of on-chip optical interconnection network architecture, a novel 5 × 5 full-duplex communication optical routing switch based on microring is proposed. A novel microring resonator switch formed by covering a layer

In this paper, based on a scale-adapted set of Laguerre-Gaussian modes, a theoretical model has been presented for evaluating the coupling efficiency of modes and mode crosstalk between different spatial modes caused by transverse offset and angular misalignments. A proof-of-model demonstration is performed for three-mode fiber, and the results show that the coupling efficiency and mode crosstalk of

In this paper, we revealed that the pseudo-3D perception of a 2D aerial image is increased by reducing the luminance and contrast of the background pattern, and by adding image movement that changes the shape and shading of the aerial image. In recent years, aerial images are used in our daily lives as entertainment, aerial touch panels etc. Most of them are 2D aerial images, but we sometimes perceive

The purpose of this study is to apply digital image processing to original images acquired with common digital devices to generate the resulting images that are easy for the elderly to see without using colorimetric values. Therefore, we propose an image enhancement method to improve color visibility of digital images for the elderly, taking account of their color vision characteristics. The proposed

Terahertz imaging technology has been widely used in security inspections due to its ability to detect various concealed hazardous materials and the advantage of being harmless to the human body. However, limited by the terahertz imaging system, it is challenging to detect concealed objects due to hard samples and imbalanced categories caused by terahertz image quality. To solve these issues, we propose

Two technologies for improving image gaps and narrow viewing angle were applied to a space-saving compact aerial display with striped retro-reflector on a LED panel. The aerial image gaps created by the striped retro-reflector structure was smoothed by scrolling the images perpendicular to the stripe direction. The narrow viewing angle inherent to the compact aerial display was successfully improved