We present a compact multimodal endomicroscope that enables simultaneous fluorescence (FL) and optical coherence tomography (OCT) imaging. While current endoscopy techniques are effective for wide-area and rapid inspection, there is a growing demand for real-time precise diagnostics, including detailed tissue morphology and tumor invasion depth. Histological analysis through biopsy remains the diagnostic standard but involves a time-consuming process that can delay treatment decisions. Our approach integrates two complementary imaging modalities—FL for visualizing tissue morphology and OCT for cross-sectional imaging—within a single probe compatible with standard gastrointestinal endoscopic channels. The system employs a Lissajous scanning mechanism to achieve forward-viewing, uniform illumination, and high-speed imaging. A compact imaging probe is fabricated by assembling a composite fiber, piezoelectric tube actuator, and asymmetrically attached polymer stiffener in parallel, enabling combined fluorescence and optical coherence imaging with complementary performance characteristics. Real-time image reconstruction is implemented using parallel computing to support high-throughput data processing. Imaging experiments on phantom targets and ex-vivo animal tissues confirm the system’s capability to produce detailed, co-registered images of tissue morphology and structure. This technology offers a promising platform for enhancing diagnostic accuracy and enabling real-time decision-making in gastrointestinal endoscopy.

Most micro-electromechanical systems (MEMS) gyroscopes use capacitive detection to sense displacement from angular velocity, but parasitic capacitance and electromagnetic interference limit precision. Micro-opto-electro-mechanical systems (MOEMS) gyroscopes replace capacitive readout with optical detection, improving sensitivity and interference resistance, yet integrating optical structures with diverse motion modes remains challenging. We propose a high-sensitivity MOEMS y-axis gyroscope based on a double-layer two-dimensional photonic crystal array (2L2DPCA). One photonic layer is fixed to the substrate and the second is attached to a movable sensing mass, which enhances light confinement and reduces optical energy loss. A dual-decoupled beam design isolates nonplanar motion and suppresses cross-coupling in the x and y axes. Simulations show excellent in-plane uniformity and coupling-error suppression. Mechanical sensitivity reaches 57.82 nm/(°/s); overall output sensitivity after optoelectronic conversion is ≈31.24 mV/(°/s). Angular random walk (ARW) is 3.77×10⁻⁵ °/h1/2 for coupling gaps d≈0.1–0.2μm. Experimental results validate rotational response and indicate real-time performance potential in engineering and aerospace environments. The proposed device combines high sensitivity, reduced noise, and robust anti-interference characteristics, improving measurement accuracy and dynamic range for compact navigation and precision sensing applications.

This article presents a bendable substrate MnxCa(0.90−x)Ni0.10Fe2O4 based metamaterial absorber for RF energy harvestingfrom Wi-Fi frequency of 5 GHz to the achievement of the Sustainable Development Goals. The bendable metamaterial absorber (BMMA) energy harvester unit cell constructed with the physical dimension of 21 × 21 mm2. The proposed unit cell consist of cross sign shaped resonator surrounded by circular ring resonator is located middle portion and boundary split outer ring resonator. Based on the simulation findings, the proposed BMMA energy harvester provides maximum absorption efficiency of 99.42% at 5 GHz. Due to the axis symmetrical design, the energy harvester unit cell shows an excellent angle insensitive up to 90 degrees for polarization angle and up to 45 degrees for incident angle, for both TE and TM modes. The proposed BMMA exhibits single negative properties, and it shows excellent absorption efficiency under convex bending conditions. The lightweight, flexibility of the structure indicate that MnxCa(0.90−x)Ni0.10Fe2O4 based bendable metamaterial absorber energy harvester have significant potential for RF energy harvesting application from Wi-Fi frequency of 5 GHz and it achieve Sustainable Development Goals (SDGs), specially alignment with SDG 7 (Affordable and Clean Energy), SDG 9, SDG 11, and SDG 13.

In this paper, we present the design and characterization of a low-power, compact, infra-red emitter array using a titanium nitride micro-hotplate fabricated in an 8-inch wafer. The device has three emitters as an array, with an area of 6.2 × 104 μm2 each emitter. We first present the design and simulation, where the mechanical structures and electrical routings of the emitters are developed considering both the thermal performance and KOH etching process requirement. Moreover, we experimentally present the electro-thermal and optical performance. The emitter has a DC power consumption of 63.75 mW, a total emission of 0.55 mW across the 2.5 to 15 μm wavelength range, a 65.6% frequency modulation depth of 100 Hz, and a maximum operation temperature of 408 °C. Given the increasing demand for low-power, high-performance IR light sources, the proposed devices are promising for gas sensing and spectroscopic analysis applications.

The demand for high-power, high-density VCSEL light sources in applications such as space, artificial intelligence, silicon photonics, and autonomous vehicles is steadily increasing. VCSEL chips are epitaxially grown on GaAs substrates and then packaged by attaching them to a mounting bracket using high-temperature-resistant adhesives. This issue limits the VCSEL’s output power, and restricts its application range. We propose first removing the VCSEL epitaxial layer from the GaAs substrate and transferring it to a CuW substrate. The VCSEL chip is then mounted on an AlN substrate using a metal eutectic bonding technique. The results indicate that bonding 36 VCSELs with a wavelength of 840 nm to CuW chips and mounting them onto an AlN substrate to form an array achieved voltage of 8.59 V and a driving current of 18 A. The output optical power reached 57.68 W, with a reduced packaging thermal resistance of 0.232 K/W.

A resonant waveguide grating structure based on periodically perforated metal slits (PPMSs) was specified in experiments for metal-slit cavity resonance in the frequency range of 0.1–1 terahertz (THz), including the structural symmetry, thickness and distributed length of a metal-slit array. In dielectric-medium perturbation experiments, 2D spatial confinement of a metal-slit cavity resonance wave in a large area was characterized with distinct transmittance dip at 0.5 THz and relevant redshift effect of glucose dispersion responsivity. This metal-slit-cavity resonance wave was thus used as an optical probe of one PPMS-based glucose refractometer for recognizing molecular density range of 0–24 µg/mm2, a resolution density of 1.6 µg/mm2, and a trace density of 2.61 µg/mm2. For a megahertz-frequency resolution of THz optomechatronic system, PPMS-based glucose refractometer potentially could realize a detection of limit lower than 2.2 ng/mm2, equaling 1.8 mg/dL, and would also be comparable to other sensing schemes of glucose through optical probes of infrared ray–visible light waves.

In this work, the complete development of a line module type silicon carbide (SiC) deformable mirror (DM) for adaptive optics (AO) is described. To eliminate the risk of fracture and misalignment during the simultaneous assembly of all actuators and the base plate of a DM, the line module concept is introduced. This line module is a pre-assembled set consisting of a line-shaped base plate to which actuators and flexures are glued in a row. This concept helps reduce the risk of actuator breakage during the assembly process while also providing flexibility by enabling the easy exchange of the line module if defective actuators are found. Flexible stand mounts are used to minimize mirror surface distortion caused by mounting. Distortions of the mirror faceplate in the complete assembly of the DM, caused by assembly tolerances, gravity, and temperature variations, are assessed through simulations. Considering the flattening of the mirror faceplate to its initial state, the distortions are found to be sufficiently low. Finally, the mirror surface stroke is checked with an interferometer, and the dynamic responses and coupling ratios are measured using a laser displacement sensor. The results show that the line module type SiC DM fulfils the design goals.

Large-sized ground telescopes have been developed to meet the high demands for opto-mechanical imaging systems in space and military applications. In line with these advancements, we developed a 1-m class ground telescope for astronomical imaging and satellite laser ranging (SLR). In a ground telescope, mirror deflection is mainly induced by gravity and temperature change. In particular, the gravity vector varies depending on the pointing direction of a telescope, so the surface deformations of the mirrors due to self-gravity need to be managed in different observation directions. This study introduces a mechanical design for an optical tube assembly (OTA) and suggests an optimized design for the secondary mirror (M2) assembly. For a kinematic positioning of the M2, its lightweight was achieved based on the partially open-back structure with hexagonal pocket cells. Then, we optimized the flexure mount design with a bipod structure to minimize the surface errors (SFEs) of the M2 in both the horizontal and vertical pointing directions. Additionally, we simulated the deflections of the primary mirror (M1) and M2 assemblies when installed on the telescope. Based on our design, the M2 was fabricated and processed, and we demonstrated its assembly process and surface quality test.

With the advancement of artificial intelligence technology, there is a growing demand for smart vehicle cockpits. As a result, the performance requirements for automotive displays are increasing. However, commonly used side-light and direct-light backlight modules, which provide planar light sources for displays, struggle to meet the demands for lightweight, thin designs with high uniformity and high luminance simultaneously. Therefore, we propose the use of zero-optical-distance Mini-LEDs in conjunction with a high-luminance composite light-guide for automotive display backlights. This approach involves a direct-side composite light guide that integrates a microstructure of the light incident surface (MLIS). The design includes embedding the light source within perforations and optimizing the curvature to enhance performance. This design expands the distribution, which increases the spacing between light sources and reduces the optical mixing distance (OMD). In this paper, we use an 8.8-inch module for experiments, with a thickness of 3 mm and an input power of 9.72 watts. The module achieves an average luminance of 72,562.3 cd/m2 and a uniformity of 90.79%. This results in a zero-optical-distance, lightweight, thin, and highly uniform high-luminance compound light-guiding planar light-source.

Photoacoustic microscopy (PAM) has emerged as a promising biomedical imaging technique, renowned for its capability to visualize the microvasculature and measure oxygen saturation levels in biological tissues, both non-invasively and in real-time. PAM combines the contrast benefits of optical imaging with the penetrating benefits of ultrasound. It offers high spatial resolution and deep tissue imaging, which is what microscopic and macroscopic imaging can’t do separately. This review presents fundamental knowledge of PAM’s theoretical model and the sensing mechanism. Using a Micro-Electro-Mechanical Systems or Microelectromechanical Systems (MEMS), various PAM optimizing techniques are covered, ranging from design, materials, and algorithms. Discussions also include opinions on future MEMS-based PAM technology development tendencies.