Optical microfiber taper has unique propagation properties, which provides versatile waveguide structure to design the tunable photonic devices. In this paper, S-tapered is fabricated by using simple fusion spicing. The spectral characteristics of integrated with ferrofluid under different magnetic-field intensities have been theoretically analyzed and experimentally demonstrated. spectrum are both found become highly magnetic-field-dependent. results indicate transmission wavelength dips...

A compact magnetic field sensor has been proposed based on multimode interference effects. It consists of typical interferometer (MMI) immersed into the fluid (MF) which is formed by a section square no-core fiber (NCF) spliced between two single-mode fibers. The transmission spectral characteristics this MMI have analyzed, and response investigated immersing NCF MF environment. maxima exhibits sensitivity −0.01939 dB/Oe in relatively linear range. Due to its low cost compactness, would find...

A simple and compact optical fiber relative humidity (RH) sensor based on SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> nanoparticles has been proposed experimentally demonstrated in this paper. S-taper is fabricated as the sensitive element using fusion spicing S-tapered region coated with a layer of hydrophilic material by direct immersion into nanoparticle solution. The resonance wavelength well peak transmission are both to...

A highly sensitive optical fiber twist sensor has been proposed by employing a Sagnac interferometer based on polarization-maintaining elliptical core fibers (PM-ECFs). The effects have theoretically analyzed and experimentally demonstrated. Based the photoelastic effect, resonance wavelength linearly shifts with increment of shift is also dependent torsion direction. maximum sensitivities reach 18.60nm/(rad/m) for clockwise (CW) direction 15.83nm/(rad/m) anticlockwise (ACW) direction,...

Remote sensing ship recognition technology is one of the important research areas for achieving ocean security monitoring. However, maritime targets features such as multi-scale, arbitrary direction, and dense arrangement, their imaging often influenced by factors sea fog surface background. It challenging fast accurate detection remote ships. We propose a new algorithm YOLO-Remote Sensing Ship Detection (YOLO-RSSD) based on YOLOv5, which effectively improves accuracy while ensuring speed....

An all-fiber twist sensor based on multimode interferometer (MMI) has been proposed and fabricated by splicing both ends of a section square no-core fiber (NCF) with single mode fiber. We have investigated the transmission spectral characteristics under different applied twisting angles. Within torsion angle range -360°~360°, wavelength sensitivities are 1.28615 nm/(rad × m(-1)) 0.11863%/ (rad m(-1)), respectively. Moreover due to trivial thermal expansion coefficient pure silica fiber, low...

An improved deep neural network incorporating attention mechanism and DSSIM loss function (AM_U_Net) is used to recover input images with speckles transmitted through a multimode fiber (MMF). The trained on relatively small dataset demonstrates an optimal reconstruction ability generalization ability. Furthermore, bimodal fusion method developed based S polarization P speckles, greatly improving the recognition accuracy. These findings prove that AM_U_Net has remarkable capabilities for...

A two-dimensional (2D) magnetic field vector sensor is proposed and experimentally demonstrated. theoretical model established to analyze the physical mechanism in detail. The transmission response of depends on angle (θ) between orientation polarization direction tilted fiber Bragg grating (TFBG) intensity (H) when keeping θ constant exhibits a sinuous behavior H constant. When -θ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> <; π - +...

A fiber-optic magnetic field sensor based on the thin-core modal interference and fluid (MF) has been proposed experimentally demonstrated. The is spliced with a fiber (TCF) between two conventional single-mode fibers immersed into MF. transmission spectra of under different intensities have measured theoretically analyzed. results show that sensitivity reaches up to −0.058 dB/Oe linear range from 75 Oe 300 Oe. Due small thermal expansion TCF material, attenuation wavelength power remain...

A dual-parameter measurement scheme based on a long-period fiber grating (LPFG) concatenated with multimode (MMF) has been proposed and experimentally demonstrated for simultaneous of magnetic field temperature. Splicing the LPFG etched MMF enables coupling between core modes different cladding as well interferences higher-order in MMF. Due to transmission mechanisms mode interference, sensor shows dip wavelength sensitivities 0.02878 nm/Oe −0.04048 nm/°C multi-mode interference (MMI)...

Abstract A laser-assisted tuning method of whispering gallery modes (WGMs) in a cylindrical microresonator based on magnetic-fluids-infiltrated microstructured optical fibres (MFIMOFs, where MF and MOF respectively refer to magnetic fluid fibre) is proposed, experimentally demonstrated theoretically analysed detail. The MFIMOF prepared by infiltrating the air-hole array using capillary action effect. fibre-coupling system set up for proposed MFIMOF-based acquire an extinction ratio 25 dB...

Ahighly sensitive refractive index (RI) biosensor based on three-layers air-holes photonic crystal fiber (PCF) with gold film the outer edge of cladding is proposed. The properties modes coupling between fundamental mode (odd mode), (even mode) and surface plasmon polaritons (SPPs) were theoretically simulated, respectively. Meanwhile, effects thickness air-hole diameter sensor performance are analyzed in detail. When energy odd even couple strongest to SPP 50 nm, maximum sensitivities this...

A magnetic field sensor based on an asymmetrical fiber modal Mach–Zehnder interferometer (MMZI) is achieved by cascading tapered with the core-offset structure. The MMZI sealed fluid and its spectral dependence has been investigated. results show that transmission variations of two dips are about 8 dB 10 for a intensity range from 0 Oe to 400 Oe, respectively. highest sensitivity reaches 0.03407 Oe−1. proposed demodulation cost-effective robust; therefore, device beneficial sensing...

A fiber-optical sensor is proposed for dual-direction magnetic field measurement by cascading an optical microfiber with a core-offset section. Due to the relative direction difference between and fiber axis, refractive index of fluid could be tuned accordingly. The transmission spectral characteristics change variation applied field. Experimental results show that different directions turn out linear responses. When perpendicular or parallel sensitivities are −0.02534 0.01111 dB/Oe,...

A compact fiber-optic magnetic-field sensor based on tapered all-solid waveguide-array fiber (WAF) and magnetic fluid (MF) has been proposed experimentally demonstrated. The WAF is fabricated by using a fusion splicer, the formed immersing into MF. transmission spectra have measured analyzed under different intensities. Experimental results show that acquired sensitivity 44.57 pm/Oe for linear intensity range from 50 to 200 Oe. All-solid very similar thermal expansion coefficient high-...

A compact and ultra-sensitive magnetic field sensor has been proposed by exploiting a microfiber-assisted Mach-Zehnder interferometer functionalized fluids. We have experimentally investigated the transmission spectral responses of to variation applied intensity environmental temperature. The interference dips exhibit sensitivity as large −1.193 nm/Oe for low range 3 Oe 21 Oe. By using sensing matrix containing well temperature sensitivities different dips, cross-sensitivity issue could be...

Metamaterials have opened up a new field of electromagnetic wave stealth that can achieve cross-band through high absorption and low infrared emission. However, traditional metamaterials make covering the terahertz band challenging certain design flaws. This Letter introduces an innovative metasurface in infrared, microwave, THz bands. We use phase change materials gradient principle to GHz absorption. also surface height-covered emitting materials, which give them lower emissivity. These...