As the next-generation human–computer interface, augmented reality display technology has been gradually popular, depending on advances in system architectures. However, existing waveguide and passive retinal projection display solutions are unable to combine their respective advantages to address increasingly demanding performance requirements. Herein, we propose an active retinal projection display (A-RPD) concept based on collimated active-matrix microdisplay panels. By deriving and validating the collimation-dependent depth of focus, the optimization direction of this architecture is emphasized. Through the direct integration of pixel-to-pixel collimators on the microdisplay panels, an A-RPD prototype featuring a balanced design and performance has been successfully constructed. It enables clear retinal imaging from 40 cm to 160 cm, which significantly surpasses that of the uncollimated microdisplay. The proposed active retinal projection architecture retains the advantages of retinal projection while simplifying the architecture. This work highlights its importance and superiority and provides foundations for its further expansion in practical applications.

Thermal infrared (IR) detectors represent a crucial technology for various applications, yet achieving high performance without cooling remains challenging. Here, we demonstrate high-performance broadband IR photodetectors by integrating single-walled carbon nanotubes (SWCNTs) with a ferroelectric substrate, leveraging the pyroelectric effect for enhanced photodetection. Using aerosol chemical vapor deposition and capillary transfer techniques, we fabricate sparse SWCNT films on z-cut LiNbO₃ surfaces to create pyroelectrically gated field-effect transistors. The devices exhibit remarkable responsivity across the IR spectrum, with semiconducting channels achieving maximum relative responsivities reaching nearly 100 %/μW at 1550 nm. Our optimized SWCNT networks demonstrate exceptional specific detectivities of 1.7 × 10¹⁰ cm$ {\sqrt{{{{\text{Hz}}}}}/{{{\text{W}}}}}$ at 1550 nm and 1.4 × 10¹⁰ cm$ \sqrt{{{{\text{Hz}}}}}/{{{\text{W}}}}$ at 9.3 μm, surpassing graphene-based alternatives by several orders of magnitude and approaching theoretical limits. These results establish SWCNT-based pyroelectric photodetectors as promising candidates for room-temperature IR detection, eliminating the conventional requirement for cooling.

Type 2 diabetes mellitus (T2DM) significantly elevates fracture risk, a severe complication often underestimated by conventional bone mineral density (BMD) assessments. Here, we applied label-free multimodal nonlinear optical (NLO) imaging with AI-powered texture feature analysis to characterize T2DM-related bone quality alterations. Our results identified aberrant spatial protein distribution, characterized by increased homogeneity and reduced contrast, as a distinctive pathological feature in T2DM bone. The alterations in spatial distribution were also observed in hydroxyapatite (HA) and autofluorescent metabolites. A K-nearest neighbor (KNN) model, trained on fused texture features from these three components, achieved a superior classification accuracy of 93.56% in distinguishing T2DM-related bone tissues, markedly outperforming single-component models (~70%). This demonstrated that fused multi-component spatial distribution features offer enhanced discriminative power for quantifying T2DM-associated pathological changes. Collectively, aberrant molecular spatial distribution, particularly of protein, represents a potentially unappreciated indicator of diabetic bone quality alterations. Integrating multimodal NLO imaging with explainable AI offers a novel approach for unraveling the mechanistic underpinnings of complex pathological alterations, which not only overcomes the limitations of conventional biomarker assessment but also establishes a powerful framework for discovering new pathological targets.

Calculus equations are fundamental mathematical tools, whose numerical solution is crucial. Existing solvers with optical analog computing struggle to simultaneously integrate programmability and parallel processing, thus constraining computational speed and density. Herein, we propose a reconfigurable all-optical platform capable of solving variable-coefficient first-order ordinary differential equations in parallel. We utilize the electrically tunable liquid crystals (LCs) as computing kernels to address these equations. The solver's applicability to canonical scientific problems, such as heat conduction and resistor-capacitor circuit dynamics, is further showcased with simultaneous solving of 158 equations with only one single forward propagation of light. Experimental results confirm the efficacy of the platform in solving equations in an ultra-fast, reconfigurable, broadband, and parallel manner.

Dissipative Kerr solitons (DKSs) generated in optical microresonators have shown considerable promise across multiple applications, particularly in metrology and spectroscopy. Multistable solitons enable on-chip single-cavity dual-comb generation, and can be excited via multicolor pumping in a microresonator featuring high-quality factor and strong nonlinearity, whose dispersion profile governs the soliton velocity mismatch. However, real-time characterization of complex multistable soliton dynamics remains highly challenging due to their transient nature, large bandwidth, and high repetition rate. In this work, we generate multistable soliton dynamics using a dual-pump scheme targeting distinct cavity modes and report, for the first time, their simultaneous time- and spectral-domain characterization via a chirped coherent detection scheme. These multistable solitons are measured at different carrier-envelope offset frequencies, allowing for the observation of soliton switching and annihilation processes during pump detuning. Furthermore, the gain transfer mechanisms underpinning the influence of pump detuning on soliton dynamics are investigated. This study not only deepens our understanding of complex soliton interactions within optical microresonators but also supports enhanced control and utilization of single-cavity dual-comb sources.

Achieving realistic depth perception in augmented reality (AR) displays remains a central challenge due to the reliance on single focal planes. In the recent work published in Opto-Electronic Science, researchers from Beijing Institute of Technology and their collaborators report a hybrid metasurface-freeform optical architecture that enables simultaneous multi-focal plane display within a compact, solid-state system. By combining polarization-multiplexed metasurfaces with freeform optics through a joint design framework, the system generates multiple depth cues without time multiplexing and remains compatible with practical display hardware. This work highlights a promising route toward cross-scale optical co-design for realistic near-eye display systems.

Indium phosphide-based quantum dots (InP-based QDs) have emerged as promising candidates for next-generation display and optoelectronic technologies, offering exceptional photoluminescent (PL) properties including high efficiency, narrow emission spectra, and precisely tunable wavelengths. Nevertheless, their widespread commercialization encounters substantial obstacles, primarily stemming from persistent challenges in synthetic control and material processing. Critical performance parameters—including photoluminescence quantum yield (PL QY, currently<90% for most systems), emission linewidth (typically>35 nm) as well as external quantum efficiency (EQE) and operational stability of device—continue to show only incremental improvements, highlighting the urgent need for fundamental breakthroughs in QDs synthesis, surface engineering and device optimization. This review systematically examines the nucleation mechanisms governing InP core formation and outlines key strategies for optimizing InP-based core/shell QDs. Furthermore, we present a comprehensive analysis of recent breakthroughs in red, green, and blue-emitting InP-based QD light-emitting diodes (QLEDs) development, focusing on modulation of charge transport engineering and suppression of charge leakage. Finally, we critically evaluate the remaining commercialization challenges and future prospects for InP-based QLEDs in next-generation display and optoelectronic technologies, outlining potential pathways for overcoming current limitations.

Bound states in the continuum (BICs) have emerged at the forefront of optics and nanophotonics due to their exceptionally high quality-factors and unique topological characteristics. Advances in design capabilities, nanofabrication and characterization have enabled precise control of BIC resonances at subwavelength scale, unlocking exciting opportunities for applications in diverse areas such as lasing, optical sensing and nonlinear optics. The integration of phase-change materials and liquid crystals has facilitated dynamic control over light emission and absorption. In this Review, we provide a comprehensive overview of the latest progress in BIC research, covering both foundational concepts and recent advances. We begin with the underlying physics and highlight emerging design strategies, including machine learning and inverse design approaches. We discuss major breakthroughs in super-BICs, chiral BICs, intriguing concepts of flatband BICs and Moiré BICs, along with exotic phenomena, such as strong light-matter interaction, ultrafast dynamics and exceptional points. We further review the recent advancements and key challenges in BIC-enabled applications. Finally, we offer our perspectives on the promising future of BIC in fundamental research emphasizing emerging directions such as multilayer metasurfaces, interfacing BICs with quantum emitters, new capabilities enabled by advanced fabrication and design, and pathways towards scalable integration into photonic BIC metadevices.

With increasing demand for ocean exploration, underwater tasks become more complex. While soft robotic hands offer superior flexibility and biomimetic advantages over rigid robotic hands, their development has been hindered by low sensing accuracy and poor interactive control. Here, we propose a light-perception-based underwater digital twin hand interactive control system that integrates a multi-degree-of-freedom biomimetic pneumatic soft robotic hand with a wearable data glove based on fiber Bragg grating (FBG) sensors. By fusing data from FBGs, RGB cameras, and inertial measurement units, and optimizing control strategies through reinforcement learning, we established a light-dominated perception-control-feedback closed-loop system that significantly enhances the control performance of the system in complex and dynamic underwater environments. With light as the information carrier, the system integrates a data glove with high strain sensitivity (1.148 pm/µε, linearity = 0.9996) and high bending sensitivity (26.667 pm/°, linearity = 0.9791). It achieves four-dimensional collaborative interactive control between the human operator, machine, virtual space, and environment. The system achieves posture monitoring and precise grasping in various underwater environments, offering advantages like low cost, high precision, rapid response, and strong interference resistance. This establishes a new paradigm for underwater intelligent equipment by integrating light sensing with digital twin technology, offering broad prospects for future underwater operations.

Unveiling the vacancy oscillation mode in amorphous binary oxides films at nanoscale and its impact on ionic conductivity and conductivity spectra is vital to explore the tightly intertwined connection between reversible oxygen migration and stabilizing and controlling the ferroelectric behavior, to complement traditional ferroelectric doped-HfO₂ materials. Using terahertz time-domain spectroscopy (THz-TDS), infrared reflection spectra, and density functional theory (DFT) calculations, we investigate the optical absorption and reflection spectra of crystalline and amorphous ZrO₂ thin film by varying oxygen vacancy concentrations. Experimental results show that oxygen vacancy migration rather than intrinsic paraelectric nature in films significantly affect the conductivity and polarization behavior of ZrO₂ thin film. Notably, except for the phonon modes induce distinct absorption peaks around 11 THz, additional absorption peaks are observed in the 1–2 THz range, which are caused by localized states originated from the oxygen vacancies, supported by DFT calculations. Temperature-dependent ion migration behavior further confirms the role of vacancy oscillation modes in ionic conductivity. DFT calculations additionally reveal how oxygen vacancies alter infrared absorption and optical modes, leading to a redshift in existing absorption peaks or the introduction of new peaks. Our findings unambiguously clarify the oxygen voltammetry characteristics in amorphous ferroelectric binary oxides films. Furthermore, the strategic deployment of amorphous binary oxides films enables the use of low-temperature atomic layer deposition (ALD) growing process, effectively alleviating routing congestion of ferroelectric oxides and offering additional design flexibility for future memory devices with ultra-low effective oxide thickness (EOT) and low thermal budget, and providing alternative technological routes that are poised to propel the development of next-generation more compact ferroelectric devices for advanced process nodes.