Insect eyes represent a paradigm of miniaturized visual systems, offering exceptional wide-field vision, high sensitivity to motion, and an infinite depth of field. In this article, a detailed analysis of the structural characteristics and functional mechanisms underpinning various natural compound eye systems is conducted, establishing a foundation for engineered design. Building on a biological basis, multiple types of biomimetic compound eyes (BCEs) with distinct configurations are designed and fabricated. Key optical properties such as angle of view, optical crosstalk, and imaging performance are evaluated. The work highlights the critical trade-offs in biomimetic design and demonstrates the influence of structural features on integration strategies and imaging outcomes. The experimental results demonstrate that the BCE-based visual systems successfully replicate the wide-field vision inherent in their biological counterparts. The findings offer valuable insights into the design, fabrication, and application of insect-eye visual systems that hold significant potential for advancing a new generation of optical devices, including miniaturized robotics, medical and industrial endoscopes, and ultracompact surveillance systems.

Based on LTCC technology, a single through-hole double-helix transverse thermoelectric generator (TEG) structure with short-distance vertical thermal drive is proposed. A staggered distribution of cold and heat sources in the longitudinal direction is established in this structure. Hence, the external temperature difference can be effectively concentrated on both sides of the transverse Y-type thermoelectric unit, reducing the thermal resistance loss. In order to solve the problem of electrode encirclement in the single-helix transverse thermoelectric array structure, a cascaded structure of double-helix thermoelectric units is designed to construct a high-density parallel power generation unit to improve the energy harvesting capacity. The experimental results show that the output voltage of the proposed 170 pairs of thermocouple double-helix transverse TEG can reach up to 231.8mV, while the maximum output voltage factor is 0.12 mV & centerdot;cm(-2)& centerdot;K-2 with the maximum output power factor of 0.004 & micro;W & centerdot;cm(-2)& centerdot;K-2. Compared with the single-helix lateral TEG, the power generation capacity of the double-helix inductance TEG is increased by 82.52%. This work can provide additional solutions for energy harvesting of micro energy.

To address the critical challenge of low thermoelectric conversion efficiency in high-temperature, highly turbulent waste heat recovery, a novel fish-fin convergent annular thermoelectric generator (FF-CATEG) device is proposed. An annular contraction-type thermal conduction ceramic component is designed along the axial gradient direction, with fish-fin-like fins and thermocouple annular arrays introduced on the inner and outer walls of the ceramic, respectively. Therefore, the directional transport through the cross-coupling of fluid kinetic energy and thermal energy is achieved, significantly improving the thermoelectric conversion efficiency of the proposed structure. Experimental validation demonstrates that the optimized FF-CATEG attains a maximum net output power of 6.17 W at a pipe contraction angle of 3.5° and a fin coverage of 13.44%. With a temperature difference of 320 K and a waste heat fluid velocity of 14.5 m/s, the thermoelectric conversion efficiency is enhanced to 3.97%, representing a substantial 39.3% improvement compared to the finless configuration. This study presents a new approach for recovering waste heat from turbulent flows.

Holographic 3D displays offer a promising solution to the vergence-accommodation conflict (VAC) but often require complex optics or suffer from limited resolution. This paper proposes a compact binocular holographic display system using a single phase-only spatial light modulator. The method employs depth-division multiplexing (DDM), where left and right views are numerically encoded at distinct axial distances using an iterative phase optimization algorithm. An optical configuration consisting of a beam splitter and a mirror maps these depth-separated reconstructions into spatially distinct viewing zones. Our method enables full-resolution binocular 3D display from a single-frame hologram, without sacrificing the resolution or frame-rate that exists within conventional spatial division. Furthermore, the framework extends to volumetric 3D display by optimizing multiple depth layers to provide correct accommodation cues. Experimental results validate that the system delivers high-fidelity binocular holographic displays with negligible crosstalk. Additionally, the proposed algorithmic framework demonstrates robust adaptability to various interpupillary distance configurations, demonstrating significant potential for compact and VAC-free near-eye 3D display applications.

Non-line-of-sight (NLOS) imaging aims to recover hidden scenes from indirect reflections, but most existing methods rely on fixed or manually tuned priors, limiting adaptability and stability across diverse conditions. We introduce a structure-guided adaptive total variation (SG-ATV) reconstruction framework that enables stable passive NLOS imaging using a conventional color camera. The key innovation is a structure-guided adaptive total variation (TV) formulation that computes spatially varying regularization weights, automatically balancing detail preservation and noise suppression and overcoming long-standing issues of parameter sensitivity and color noise in passive NLOS reconstruction. The framework dynamically adjusts the regularization weights throughout the iterative process, eliminating manual tuning. Structural information extracted from a fast preliminary reconstruction is used to construct a guidance map that robustly steers the subsequent optimization across different scenes and noise conditions. Experiments demonstrate that the proposed method improves reconstruction efficiency by approximately 30 times while maintaining high robustness and generalization. In terms of quality, it increases the peak signal-to-noise ratio (PSNR) from 17.52 dB to 58.92 dB and reduces color deviations (ΔE = 0) from 28.6 to nearly zero, achieving near-perfect color and structural fidelity. Moreover, the proposed prior-guided mechanism provides a scene-independent weighting strategy that can be directly integrated into other TV-based or optimization-driven NLOS reconstruction pipelines, offering broader applicability without additional parameter tuning.

Accurate identification of disease vectors is crucial for public health, yet distinguishing morphologically similar species demands significant taxonomic expertise and data resources. This study proposes MVP-Net, an AI-driven framework designed to extract a minimal sufficient set of diagnostic anatomical views from multi-view imagery for efficient identification. The framework was evaluated on regionally collected datasets of Calyptratae (8 views) and Culicidae (11 views) from routine surveillance in Shanghai. Under all-view fusion, MVP-Net achieved Top-1 accuracies of 87.04% for Calyptratae and 100% for Culicidae. After Pareto-based view optimization, the required input was reduced to 5 views for Calyptratae and 2 views for Culicidae, lowering computational cost by 37.49% and 81.82%, respectively, while retaining comparable classification performance (86.11% for the recommended Calyptratae configuration and 100% for the recommended Culicidae configuration). These results show that MVP-Net can reduce view redundancy while preserving comparable identification performance within the current Shanghai surveillance setting, providing a practical approach for optimizing regional multi-view auxiliary identification workflows.

Holographic near-eye display (HNED) is currently a promising technology capable of providing all the three-dimensional (3D) visual cues for human eyes. However, the generation of a computer-generated hologram (CGH) always relies on the repetitive computation of diffraction propagation from point-cloud or multiple depth-sliced planar images, which inevitably leads to an increase in computational complexity. This paper presents an efficient computation method of CGH based on applying a Programmable Digital Free-form Lens Phase (PDFLP) in the calculation of diffraction. Our approach encodes the depth information from an RGBD image directly into a programmable free-form lens phase profile, enabling the generation of a 3D hologram from a 2D image through a single-step angular spectrum diffraction calculation, thereby significantly reducing computational complexity. Compared to traditional layer-based methods, the computational speed of the proposed approach is independent of the number of quantization layers, thus enabling real-time computational speed even under very dense depth sampling. Both simulation and experimental results validate the proposed method.

To alleviate visual fatigue caused by the vergence-accommodation conflict (VAC) in conventional near-eye displays, we propose a compact binocular holographic display architecture based on a single phase-only spatial light modulator (SLM). A customized frequency-domain polarization multiplexing mask integrated into a 4-f optical relay enables physical separation of the two viewing channels, allowing independent wavefront reconstruction of two viewpoints. In addition, a dual channel band-limited polarization-multiplexed optimization framework with a 39.77% spectral utilization ratio is employed to generate multi-depth holographic 3D images with accurate focus cues. Both numerical simulations and optical experiments demonstrate high-fidelity reconstruction with a peak signal-to-noise ratio (PSNR) up to 28.08 dB and a structural similarity index (SSIM) up to 0.9608, validating the feasibility of the proposed system for compact next-generation AR/VR holographic displays.

Holographic display technology holds immense potential in augmented reality (AR) and virtual reality (VR). However, traditional color holographic display methods typically employ sequential illumination by synchronizing red, green, and blue (ROB) illumination with holograms of each individual component, which reduces the effective frame rate by a factor of three. The depth division multiplexing (DDM) technique can employ simultaneous ROB illumination over the spatial light modulator (SLM) and maintain the full SLM frame rate. The single-frame hologram is iteratively optimized by assigning each color component to different depth planes. However, since it explicitly defines content at multiple planes, it suffers from significant inter-plane crosstalk noise between colors. To overcome such limitations, we propose an optimization method for single-frame color hologram generation based on stochastic gradient descent (SOD). By formulating a dedicated loss function, the method directly optimizes the phase distribution to suppress crosstalk between different color components, while simultaneously enabling the use of the full SLM frame rate within a compact and simple optical setup. Experimental results demonstrate that, compared with traditional approaches, the proposed method significantly enhances the performance in single-frame-based color holographic displays.

Holography enables true 3D projection and displays, but speckle noise will seriously influence the quality of reconstructed images in holographic displays. For micromirror device (DMD) based holographic near-eye display systems, binary modulation exacerbates this issue by introducing quantization noise and amplifying inter-pixel interference. In this paper we propose a framework combining pixel separation into temporal multiplexing based speckle suppression. In pixel separation, we segment a target image into sub-frame consists of separated light spots, which reduces voxel overlap to mitigate interference and breaks random phase disorder. The sub-frames with different sampling offsets are then displayed sequentially via the DMD's high frame rate to reproduce a non-fragmented and speckle suppressed holographic image. Experiments demonstrate high-contrast, low-speckle 3D images, advancing applications in potential virtual reality (VR) and augmented reality (AR) displays.

Conventional metasurfaces are inherently frequency-selective, limiting wavefront control to a single operating frequency. Achieving independent manipulation at multiple frequencies remains a significant challenge for expanding the capabilities of integrated optics. Here, we propose and demonstrate an all-silicon metasurface platform that enables arbitrary independent wavefront shaping at two distinct terahertz frequencies. Our design leverages meta-molecules that synergize geometric and propagation phases to decouple the phase profiles for each frequency under a single polarization. This work provides a versatile platform for spatial-domain multiplexing, paving the way for high-capacity communication and multifunctional terahertz photonic devices.

Edge detection plays a crucial role in fields of industrial inspection and medical imaging, where extraction of object contours is essential. Conventional digital approaches often require significant computational resources, increasing system complexity and power consumption. In this work, we present a metalens-based near infrared imaging system that directly performs edge extraction during imaging. By leveraging subwavelength structures to spatially manipulate the light field, the metalens acts as a compact optical differentiator, enabling real-time edge detection without the need for subsequent digital processing. The metalens has a diameter of 200 μm and a high numerical aperture (NA) of 0.7. Its fabrication complexity is reduced through a single Pancharatnam-Berry (PB) phase design. The metalens is manufactured via two-photon lithography. Both simulations and experimental results demonstrate the effectiveness of the metalens in finding edge information. This approach significantly reduces the burden on image processing and paves the way toward compact, low-power, and high-speed imaging solutions suitable for applications in near-infrared vision and automated inspection.

Based on shared-via low temperature cofired ceramic (LTCC) technology, a heterogeneously integrated chain-type micro thermoelectric generator (& micro;TEG) is proposed in this work. The multilayer LTCC process enables a vertically interwoven thermoelectric arm configuration based on a shared hot-cold metal layout, which increases lateral integration density and reduces the effective thermal transport length. Large-aperture metallized vias are implemented as combined vertical thermal pathways and electrical interconnects, facilitating coupled transverse electrical conduction and longitudinal heat flow. The thermoelectric performances are experimentally characterized using cavity aluminum plate to regulate heat-flux distribution. The fabricated & micro;TEG incorporating 64 pairs of interwoven thermocouples achieves a voltage factor of 2.35 & times;10-1mVcm-2K-1 and a power factor of 1.87 & times;10-2 mu Wcm-2K-2 under temperature difference of 90 K. Relative to a bilayer transverse thermoelectric generator fabricated with the same LTCC process, the power generation capability of the proposed structure is increased by 70.1%. This work presents an effective method for capturing thermal energy in high-density integrated power components.

Longitudinal multifocal metalenses are pivotal for miniaturized multimagnification and 3D imaging, yet integrating tailored multifocal distributions, achromaticity, and polarization multiplexing in a single-layer design remains challenging. Here, we report a nanoprinted geometric-phase metalens that generates a longitudinally separated triple-wavelength multifoci, each wavelength producing three independent foci. The spatial overlap creates hybrid foci featuring a discrete-wavelength achromatic primary focus alongside companion foci, with fully tailorable polarization and intensity. Utilizing the optimized two-photon polymerization lithography, we achieve a 650 nm lattice period and an aspect ratio of similar to 16, overcoming prior limits in phase sampling and diffraction loss. The fabricated metalens exhibits axial chromatic aberration below 1 mu m and near-diffraction-limited focusing. Two prototypes are demonstrated for coherent red-yellow-green characterization and incoherent red-green-blue imaging, both enabling high-quality achromatic multimagnification. This strategy provides a compact, low-cost route toward integrated metalens optical systems.

Polarization multiplexing enhances communication capacity but faces material limitations requiring complex device cascading. This paper proposes a strategy for generating multiple polarization states by combining geometric phase and propagation phase in spatially interleaved meta-atoms. This strategy enables the simultaneous generation of scalar (including linearly polarized, circularly polarized) and vector beams (VBs) in the transmitted wave, along with precise wavefront shaping capabilities for these distinct polarization states. Two all-silicon terahertz metasurfaces are designed that are capable of independently manipulating both the phase and amplitude of different polarization states in transmission. The first metasurface achieves focusing with multi-polarization states under left-handed circularly polarized (LCP) illumination, while the second realizes longitudinal focusing of vortex beams exhibiting multiple polarization states under LCP excitation, with each vortex beam carrying unique topological charges. This approach paves new avenues for advanced terahertz polarization manipulation, offering significant potential for next-generation communication and secure information transmission.

Concentration measurement has important applications in many fields, including pollution assessment in environmental science and drug dosage calculation in biomedical research. In the conventional methods, concentration is determined by measuring absorbance along a fixed long optical path. However, it is not suitable for high-concentration measurement. Herein, we have proposed a few-step variable optical-path-length slope method (fs-VOSM) for ultrabroad dynamic-range concentration measurement. As a proof of the method, we devised an fs-VOSM system in which a reference path is included to enhance the accuracy and repeatability. The measurement is conducted at 5 positions along ultrashort optical path (0-20 μm) for 800 ms. In the measurement of potassium dichromate solution concentration, the fs-VOSM system exhibits a wide dynamic range from 0.879 to 70.726 g/L with coefficient of variation (CV < 1.4%) and high accuracy (relative error within ±3.5%). We prospect that the fs-VOSM can be widely adopted in many advanced instruments such as process analyzer, flow injection analyzer, and turbidity meter.

Viscosity is an inherent frictional characteristic of fluids that enables them to resist flow or deformation, thereby reflecting their flow resistance. It is significantly affected by concentration, but traditional viscosity measurements are limited to discrete concentrations, and multiple experiments are required for different concentrations, so the process is time-consuming. To overcome this limitation, this study presents a “viscosity–diffusion coupling” measurement system using a liquid-core cylindrical lens (LCL) as both the diffusion chamber and imaging element. It captures concentration profiles via focal plane imaging and solves Fick’s second law and Stokes–Einstein relation numerically to determine the viscosity at varying concentrations. Experiments on the viscosity of glycerol solutions (0–50% mass fraction) at three temperatures were conducted and showed strong agreement with literature values. The method enables continuous viscosity measurement across varying concentrations within a single experiment, demonstrating reliability, accuracy, and stability in the rapid assessment of concentration-dependent viscosity.

Arthropods have intricate compound eyes and optic neuropils, exhibiting exceptional visual capabilities. Combining the strengths of digital imaging with the features of natural arthropod visual systems offers a promising approach to harness wide-angle vision and depth perception while addressing limitations like low resolving power. Here, we present an artificial intelligence–assisted biomimetic system modeled after arthropod vision. We developed a biomimetic compound eye camera with an effective pixel number of 4.3 megapixels capable of producing full-color panoramic images with a viewing angle of 165° and resolving power of 40 micrometers. Using rich visual information, our system achieves high-fidelity image reconstruction, precise 3D position prediction, high-accuracy classification, and pattern recognition through a multistage neural network. Moreover, our compact biomimetic visual system can simultaneously track the 3D motion of multiple miniature targets independently. The proof-of-concept biomimetic arthropod visual system offers a computational panoramic imaging solution, advancing applications in industry, medicine, and robotics.

Metal-Organic Frameworks (MOFs) have shown great promise in environmental protection, owing to their exceptional properties including ultrahigh surface area and porosity, tunable pore size, and easy chemical functionalization. However, emerging evidence from experimental studies indicates that MOFs have side effects on human health due to metal ions doping, resulting in excessive reactive oxygen species (ROS) production, pro-inflammatory responses, and liver fibrosis. In this study, we investigated the impact of MOF-199 on human bronchial epithelial (HBE) cells by using transcriptome sequencing analysis. The results indicated that the stimulation of MOF-199 enhanced ROS generation, upregulated cytoplasmic Ca2+ levels, then activated the Grb2/SOS/Ras/Raf pathway, induced cell apoptosis, and ultimately resulted in lung fibroblasts through TGF-β secretion. The results were validated in vitro and in vivo. Therefore, it is necessary to carefully evaluate the nanosafety of MOF-199 in environment treatments.

Computer‐generated holography (CGH) has advanced the development of human‐centric holographic near‐eye displays. Recent work has proposed an end‐to‐end convolutional neural network that converts 2D images into 3D holograms, enabling real‐time 3D holographic displays from widespread available images. However, the high computational cost of deep learning‐based methods limits their practical application. Deploying such algorithms on resource‐constrained mobile platforms requires more efficient models with reduced computational memory and power demands, which plays a crucial role in promoting human‐centric virtual reality/augmented reality displays. In this article, a lightweight 3D hologram generation model is proposed using neural network quantization from the input of single 2D image. Specifically, a 2D‐to‐3D CGH model is quantized from 32‐bit floating‐point to 8‐bit integer precision. The results show that the INT8 model reduces size by 60%, improves processing speed by a factor of three, and achieves comparable hologram quality to the FP32 model. This work enables the practical deployment of 2D‐to‐3D CGH model on low‐power platforms, bridging the gap between high‐performance holographic computation and real‐world wearable display systems.