Diffractive optical elements (DOEs) are specialized components that manipulate light through diffraction for various applications, including holography, spectroscopy, augmented reality (AR) and virtual (VR), detection ranging (LiDAR). The performance of DOEs is highly determined by fabricated materials fabrication methods, in addition to the numerical simulation design. This paper presents a microfabrication technique optimized DOEs, enabling precise control critical parameters, such as...

The humidity has often been measured through a single point sensor. Where, the could be varied at different locations as well depending on environmental conditions. present paper developed dual measuring sensor by using polymer optical fiber (POF) based illuminating fiber. sensor's basic structure is to twist two fibers and bend them certain radius. However, cascading of twisted micro (TMB-1 TMB-2). twisting couples light from one another side coupling method. An increase in level leads...

Abstract An improved Fourier modal method (FMM) is developed for the design of metasurface diffractive optical elements (DOEs), which combines iterative transform algorithm (IFTA) with FMM. In which, IFTA executed a coarse solution; then, FMM precise solution. We take 5 × DOE nanorods as an example to explore (IFTA + FMM). By varying diameter on DOE, spot array has been created diffraction angle 48°× 48° in far field. The analysis results show that FMM) requires fewer iterations, about 17...

The emissions of volatile organic compounds (VOCs) from two new furniture including footstool and bedside table, were measured in an environmental chamber. Nine VOCs benzene, toluene, ethylbenzene, m/p-xylene, o-xylene, styrene, n-undecane, n-butyl acetate identified quantified by thermal desorption gas chromatography. effect loading rate (the ratio the surface area to chamber volume) on was investigated. release dominant organics differed with significant differences observed at different...

In the method of monitoring liquid level based on ultrasonic impedance, near-field effect can seriously affect validity results. this paper, we explore factors affecting length near field. Based that, propose optimal and minimum buffer block to avoid The evaluations show that when parameters probe are 15 mm in diameter, 1 MHz frequency, ±15 V emitted wave amplitude, best results obtained is 22 mm. When diameter 10 mm, should be ≥5 ensure measured evaluation precision This research...

A refractive index (RI) sensor based on plastic optical fiber (POF) with narrow groove structures coated a gold layer (POF-NGS (Au)) is proposed and demonstrated. The was characterized using intensity interrogation, where the change in transmission power induced by light filed interaction Surface Plasmon Resonance (SPR). Narrow lengths of 5 mm were fabricated an ultraviolet laser, sputtered to surface whole fiber. effect machining pitch RI response studied. In this paper, dB $\mu \text{W}$...

Abstract A novel high sensitivity relative humidity (RH) sensor was proposed by using micro structure plastic optical fiber (POF) based on the surface plasmon resonance (SPR) effect and evanescent wave (EW) loss. The fabricated POF coated with a gold layer agarose, adopting sputtering dip-coating technique. These construction effects attenuation of power caused SPR EW loss were used to perform RH detections. agarose’s different refractive indexes (RIs) fluctuations in transmission when...

In this study, a novel high-reliability liquid leakage sensor with V-shaped defect coupling structure (VDCS) is proposed and experimentally demonstrated using polymer optical fibers (POFs) based on light-emitting diode (LED) side-coupled light source. Liquid detection achieved changes in the refractive index as medium transforms from air to liquid. The LED lamp both provides source assists positioning. efficiency of POF varies depth angle VDCS. Experimental results show that high when VDCS...

An approach to improve the side-coupling ratio of macro-bend polymer optical fiber (POF) coupler is proposed in this paper. Two naked POFs are twisted and twined around a cylinder achieve continuous liquid level sensing. Through filling gap between two with UV cement, both sensitivity measurement range increased substantially. The reversibility also improved since eliminated, little can exist structure decreasing. design turns out be good method enhance performance, could applied...

Topology architecture has a decisive influence on network reliability. In this paper, we design novel redundancy topology and analyze the structural robustness, number of redundant paths between two terminal nodes, reliability proposed by using natural connectivity time-independent time-dependent pair reliability, k-terminal all-terminal comprehensively quantitatively, compare these measures with AFDX in three scenarios. The evaluations show that robustness analysis, when no nodes are...

Background: Postpartum haemorrhage (PPH) is a serious complication and cause of maternal mortality after delivery. This study used machine learning algorithms new feature selection methods to build an efficient PPH risk prediction model provided ideas reference for management. Methods: The clinical data women who gave birth at Wenzhou People's Hospital from 1 January 2021, 30 March 2022, were retrospectively analysed, the divided into high group (337 patients) low (431 based on amount blood...

The three polypyrrole (PPy) films with different mixture ratios, namely PPy1, PPy2, and PPy3, were synthesized by chemical oxidation pyrrole ferric chloride (FeCl3). roughened plastic optical fiber (POF) taper assembled PPy (POF-PPy1, POF-PPy2, POF-PPy3) facilely prepared bent U shape structure for testing ethanol gas at room temperature. morphologies of the POF studied using electron microscopy. effect on response was investigated results showed that POF-PPy2 exhibited a high sensitivity...

Selecting and designing the optimum ultrasonic probe is vital for measurements experiments. The amplitude of emitted wave excitation signal as well diameter natural frequency seriously affect validity results. In this paper, we analyze significance key parameters theoretically. Further, an external fixed-point liquid level monitoring system was assembled according to principle reflection transmission. On experimental platform, study that evaluation through a simulation experiment, select...

An optical fiber liquid level sensor based on two twisted polymer fibers twining around a racetrack column is demonstrated in this study. The side-coupling power of the passive modulated by refractive index (RI) environment medium and decreases while increases. variation patterns bent section straight form step attenuation, which can improve measurement range with superior sensitivity distinguish liquids different RIs. Furthermore, cost-effective also shows good reversibility low...

A quasi-distributed liquid leakage (QDLL) sensor in local area is proposed and experimentally demonstrated, providing a real-time yet low-cost method than the existing QDLL sensor. The mainly consists of flexible lamp belt (FLB) with light-emitting diodes (LEDs) polymer optical fiber (POF) processed side-coupling structures. structures are illuminated by LEDs one one, forming series sensing probes. lights side-coupled into POF through structure pulse sequences obtained from power meters...

We experimentally demonstrated the enhanced propulsion of 250 nm gold nanospheres using an optical nanofiber decorated with five nanoparticles. By tuning input laser wavelength to 808 nm, phenomenon occurred due excitation local surface plasmon resonance (LSPR) Simulated results indicate considerably scattering force on provided by LSPR, which lead velocity. The velocity was measured be about 10 times larger for LSPR nanoparticles than conventional evanescent field around nanofiber.

We experimentally demonstrate an optical transportation and controllable positioning of polystyrene nanospheres using a 3 μm diameter microfiber. By placing the microfiber in microfluidic channel injecting 980 nm laser light into fiber, suspended water were stably trapped to delivered along direction propagation. Furthermore, by increasing velocity fluid opposite light, it was found that, once increased 6 μm/s, spheres stopped their forward progress halted on microfiber, so realized.

Gold nanoparticles are gaining increasing attention due to their biological and medical applications. In this letter, we experimentally demonstrate the optical manipulation of 250-nm-diameter gold along an nanofiber (550 nm in diameter) injected by 808-nm laser light. The situated evanescent field trapped gradient force move direction light propagation scattering force. velocities reach as high 132 μm/s at power 80 mW.

A simple and low-cost continuous liquid-level sensor based on two parallel plastic optical fibers (POFs) in a helical structure is presented. The change the liquid level determined by measuring side-coupling power passive fiber. ratio increased just filling gap between POFs with ultraviolet-curable cement, making proposed competitive. experimental results show that declines as rises. sensitivity measurement range are flexible affected geometric parameters of structure. higher 0.0208 μW/mm...

A multipoint liquid level sensor based on the RI modulation of macrobend polymer optical fiber (POF) couplers is proposed. By twinning two twisted POFs around a race-track column, series U-shaped sensing heads are achieved. The output power in passive declines step form while immersed into turn. introduction UV cement gap between improves side-coupling ratio, increasing attenuation per step. For measurement range 100 cm, resolution 2 cm. can differentiate different liquids with low...