66 results about "Single-mode optical fiber" patented technology

This invention discloses an FBG strain sensor based on misaligned fusion spliced ​​coreless optical fiber and its fabrication method. The sensor comprises an input single-mode fiber, multiple segments of coreless optical fiber, and an output single-mode fiber connected sequentially. The input single-mode fiber is fused together with the first segment of the coreless fiber in a misaligned manner, and the next segment of the coreless fiber is fused together with the previous segment in a misaligned manner, with the misalignment direction of the next segment opposite to that of the previous segment, but the misalignment distance being the same. The output single-mode fiber and the last segment of the coreless fiber are fused together axially. The central axes of the input and output single-mode fibers are collinear, and the cores of the input and output single-mode fibers are connected by a photolithographically written straight waveguide. A fiber Bragg grating is then optically etched along the straight waveguide. This invention uses femtosecond lasers to fabricate the FBG on the misaligned fiber structure, increasing the structure's strain response and making the strain sensitivity of the FBG on this structure higher than that of an FBG fabricated on ordinary silica optical fiber.

This invention discloses a multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping, comprising a 1.5μm Brillouin pump, a 1.45μm tunable broadband Raman pump, a wavelength division multiplexer (WDM) I, and a passive fiber. The 1.45μm tunable broadband Raman pump includes a wavelength-tunable cascaded random Raman fiber laser, a WDM II, and a single-mode fiber I. The wavelength-tunable cascaded random Raman fiber laser is injected into the single-mode fiber I through the WDM II. This multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping provides a 1.45μm tunable broadband Raman pump source by back-Raman amplification of the broadband seed light. Working together with the 1.5μm Brillouin pump, it can achieve ultra-wideband multi-wavelength random fiber laser output. By simultaneously tuning the output wavelengths of the Brillouin pump and the Raman pump, wavelength tuning of the broadband multi-wavelength random fiber laser can be achieved.

This utility model discloses a broadband high-speed photodetector module, including: a housing and a driving circuit. The housing has an internal mounting cavity, a high-speed broadband response photodetector, and is fixed inside the housing via an SMA interface. An OLED display screen is embedded on the front of the housing and connected to the driving circuit via a flexible circuit board. The high-speed broadband response photodetector has a spectral response range of 800nm ​​to 1650nm, fully covering the wavelength requirements of multimode and single-mode optical fibers. It solves the limitations of traditional modules with single wavelength or narrow spectrum, significantly improves compatibility with different optical fiber systems, and is suitable for complex hybrid optical fiber network scenarios. Through the coordinated design of the cylindrical body on the side wall of the housing, the air outlet, and the heat dissipation components, the heat generated by the photodetector during operation can be quickly dissipated, avoiding performance degradation or device damage due to temperature rise, and ensuring long-term stable operation of the module under high-speed and high-load conditions.

The application discloses an optical metamaterial fiber coating composite process and relates to the technical field of fiber coating. The optical metamaterial fiber coating composite process comprises the following steps: S1, raw material and equipment preparation: selecting a fiber base material, a metamaterial coating raw material and auxiliary modified raw material, the fiber base material being one of a single-mode optical fiber, a PA66 polymer fiber or a glass fiber, the purity of the metamaterial coating raw material being greater than or equal to 99.5%; selecting a coating equipment, a plasma cleaning machine, an ultrasonic cleaning machine and a low-temperature annealing furnace, completing equipment debugging and calibration and ensuring that equipment operation parameter errors meet preset standards. The optical metamaterial fiber coating composite process is convenient for applying a constant extrusion force to the glue during coating and compounding, the glue can enter the inside of the fiber base material, coating and compounding are more sufficient, and the quality of coating and compounding is improved.

The utility model discloses a kind of non-contact optical coherence elastic imaging endoscope devices, comprising: non-contact ultrasonic excitation and optical detection integrated probe and high-speed sweep frequency laser, the integrated probe includes air-coupled ultrasonic transducer, collimating optical fiber, off-axis parabolic mirror and polymer resin packaging shell, air-coupled ultrasonic transducer diameter is not greater than 2.5 mm, center frequency is not less than 250 kHz, collimating optical fiber is single-mode fiber and emission end integrated collimator is used to produce collimating beam, off-axis parabolic mirror focal length is greater than 7 mm, the polymer resin packaging shell is used to integrally package integrated probe, the polymer resin packaging shell is designed using 3D printing, and it is windowed at the exit end of the off-axis parabolic mirror;The scanning speed of this high-speed sweep frequency laser is 100 kHz, center wavelength 1310 nm, bandwidth 100 nm, synchronous output trigger clock and sampling clock.

This invention discloses a simple, multifunctional, integrated 5G analog fronthaul in-band full-duplex communication method for remote units (RUs). This method primarily relates to the fields of optical communication technology and microwave technology. The system structure of the method, as shown in Figure 1 of the specification, includes a laser, downlink vector signal, electrical local oscillator signal, downlink interference signal, target signal, reference signal, 90° electrical coupler, dual-polarization quadrature phase-shift keying modulator, phase modulator, single-mode fiber, optical coupler, polarization beamsplitter, polarization beam combiner, polarization controller, polarizer, and photodetector. The remote unit (RU) uses a single phase (PM) modulator to achieve self-interference cancellation (SIC) combined with anti-fiber dispersion transmission and down-conversion, eliminating the need for bias control and additional local oscillator (LO) branches, resulting in a simple structure. At the central office (CO), the carried downlink signal and local oscillator signal are single-sideband modulated to achieve anti-fiber dispersion transmission. The RU uses wavelength reuse technology to perform PM cascaded down-conversion on the signal received from the uplink, and the SIC is moved from the RU to the CO to simplify the RU. The entire link has no optical filter and is reconfigurable.

This application discloses a distributed fiber optic vibration sensor wiring method and wiring device for bridge structures. The method includes the following steps: determining the key monitoring areas of the bridge; deploying a wiring device in the key monitoring areas; sequentially passing single-mode optical fibers through the fiber inlet and outlet ports to obtain an optical fiber sensing network; winding the single-mode optical fibers according to a set method to form redundant fiber segments; using cyanoacrylate adhesive to couple and fix the straight segments of the main optical fibers along the centerline of the bridge structure to the bridge surface; dynamically adjusting the number of winding turns of the redundant fiber segments by controlling the servo motor in the wiring device according to the real-time vibration frequency and amplitude of the bridge; by deploying a wiring device with redundant optical fibers in the key monitoring areas, the density of local optical fiber sampling points is increased by utilizing the redundant segments to meet the bridge monitoring requirements; and the winding speed is dynamically adjusted by the servo motor to ensure that the optical fibers maintain constant tension during storage and deployment, thus avoiding damage to the optical fibers.

The application discloses a fiber Bragg grating soil pressure sensor and a manufacturing method thereof, and solves the problems of small range, poor dynamic matching with the rock-soil medium and insufficient high-frequency signal capturing capacity of the existing sensor. A linear groove is arranged on the inner bottom of a circular box-shaped shell, a first single-mode optical fiber with a fiber Bragg grating is arranged in the linear groove, and protection and sealing are performed on the first single-mode optical fiber. When a dynamic impact soil pressure acts on the circular box-shaped shell, elastic deformation occurs according to the small deflection plate shell theory. The deformation is transmitted to the fiber Bragg grating, and the center wavelength of the FBG is shifted. Through the establishment of a linear mapping relationship between the pressure and the wavelength shift of the FBG, the wide frequency response characteristic is ensured while the large-range dynamic impact soil stress measurement is realized, and the high-frequency signal capturing capacity of the FBG is greatly improved.

This invention discloses a three-dimensional waveguide glass chip based on CPO (Continuous Photonic Optical Array) with an integrated weak-reflection grating sensor array, relating to the field of integrated photonic sensors. The three-dimensional waveguide glass chip of this invention has a multi-core single-mode fiber array connection unit on the left end and a single-mode multi-core fiber optic connection unit on the right end, connected in the middle by a femtosecond laser direct-write multi-channel three-dimensional waveguide. The end directly connected to the optical chip also integrates a weak-reflection fiber grating for temperature measurement. Simultaneously, multiple three-dimensional waveguide glass chips connect to the optical chip, forming a grating temperature sensing array. The signal processing end uses host computer software to perform real-time online monitoring of optical loss and the periphery of the optoelectronic chip interface. This three-dimensional waveguide high-density optical connector with an integrated weak-reflection grating sensor array for CPO applications features low loss, low power consumption, high capacity, and multifunctionality, and can monitor chip temperature and interface quality using non-primary communication bands.

The application provides a fiber sensor for high-frequency vibration detection, comprising a sensor diaphragm which is a deflected-hole fiber sensor diaphragm or a deflected-slot fiber sensor diaphragm, and a single-mode optical fiber, a light source, a circulator, an amplifier and a collection card connected in sequence; the deflected-hole fiber sensor diaphragm and the deflected-slot fiber sensor diaphragm are formed by presetting a plurality of holes or arc-shaped slots on the diaphragm which are not overlapped with the geometric center of the diaphragm and are symmetrically distributed, then the plurality of holes or arc-shaped slots are collectively deflected relative to the geometric center of the diaphragm, so that the holes or arc-shaped slots on the diaphragm finally present an asymmetric structure. The sensor device has the characteristics of high sensitivity, strong anti-interference ability and convenient production, and greatly increases the range of frequency domain response compared with the sensor made of the traditional diaphragm.

The invention discloses a sensing probe assembly, a fluidic optical fiber sensing system and a preparation method, and relates to the cross technical field of optical fiber sensing technology and microfluidic detection. One free end of a single-mode optical fiber in the sensing probe assembly is fixed to the outer wall of a first square capillary tube through ultraviolet curing glue, and a second square capillary tube is coaxially or parallelly inserted into an inner cavity of the first square capillary tube. A uniform air gap is formed between the inner wall of the first square capillary tube and the outer wall of the second square capillary tube, a microfluid channel is formed in the middle of the second square capillary tube, and broadband light beams emitted from the single-mode optical fiber are vertically incident. The micro-fluidic chip sequentially penetrates through the ultraviolet curing adhesive, the upper wall of the first square capillary tube, the air gap and the upper wall of the second square capillary tube, enters the micro-fluidic channel filled with liquid to be detected, then penetrates through the lower wall of the second square capillary tube and finally reaches the lower wall of the first square capillary tube. The probe has the advantages of high detection sensitivity, strong light beam coupling stability and the like.

This invention belongs to the field of fiber optic sensing technology, and discloses an integrated fiber optic sensor for seawater temperature, salinity, and depth based on a composite microstructure and its fabrication method. A single-mode fiber, a first coreless fiber, and a graded-index fiber are sequentially fused together to form a collimation structure for long-distance beam transmission. One end of the graded-index fiber is sequentially connected to a hollow-core fiber and a second coreless fiber. The core of the hollow-core fiber is filled with polydimethylsiloxane, located at the intersection of the cores of the graded-index fiber and the hollow-core fiber. The microsphere structure is divided into a cladding cavity and an air cavity from the outside to the inside. One end face of the second coreless fiber intersects with the air cavity and cladding cavity of the microsphere structure. Test results show that the integrated fiber optic sensor for seawater temperature, salinity, and depth based on the composite microstructure has the potential for integrated measurement of seawater temperature, salinity, and depth parameters.

This invention discloses a low detection limit fiber optic gas sensor, comprising an input single-mode fiber, a tapered fiber, and an output single-mode fiber. A PDMS / MOF gradient composite film is uniformly distributed in the waist region of the tapered fiber. In the PDMS / MOF gradient composite film, the MOF doping gradient decreases from the outer surface towards the waist region. This sensor, by distributing the PDMS / MOF gradient composite film in the tapered region, leverages the excellent gas adsorption capacity of MOF, the light transmittance and gas permeability of PDMS, and the gradient design of MOF doping to further improve sensor sensitivity and reduce manufacturing costs. Combined with the sensitization mechanism of the dispersion inflection point of the tapered fiber structure, it achieves low detection limit gas detection. Furthermore, the fabrication method is simple and inexpensive.

The utility model relates to elevator intercom technical field, concretely is a kind of elevator two-way visual intercom system for subway station, including elevator side part, transmission layer architecture and car control room side integrated system, elevator side part is integrated car terminal, five-way intercom unit and dome camera by distributed POE equipment, transmission layer uses single-mode optical fiber backbone network and VLAN isolation technology to realize low-delay audio and video transmission, car control room side is integrated SIP protocol stack, video management and information publishing function by industrial-grade host computer, support one-key lock elevator and multi-elevator split-screen monitoring. System is compatible with existing elevator intercom equipment through five-way intercom converter, realize new and old system intercommunication, solve the problem that traditional scheme wiring is complex, response delay is high, function is single, significantly improve emergency rescue efficiency.

The present invention relates to a DC electric field sensing system with a rotating structure, so as to achieve accurately measuring the DC electric field. The system includes a laser, a rotating structure, and a detector, wherein the rotating structure includes a single-mode fiber-optic slip ring, a collimator lens, a polarizer, a quarter-wave plate, a crystal, and a multi-mode fiber-optic slip ring. Experimental results show that the technical solution has advantages such as fast response, and strong resistance to electromagnetic interference, and makes it possible to inhibit beam deviation, achieve beam collimation, and enable high-precision measurement, by using the rotating structure and the fiber-optic slip ring.

Silicon photonics technologies adds integrated optics functionality to CMOS integrated circuits thereby leveraging high volume manufacturing. Independent of geometry or technology these silicon photonic devices require packaging with single mode optical fibers to interface to the optical network and / or co-packaging with active semiconductor devices, discrete microoptoelectromechanical systems (MOEMS)s or monolithically integrated MOEMS. Stringent performance constraints and minimizing manufacturing costs / times are consistent demands on such photonic circuits. Accordingly, there is a demand for low-cost and low-loss optical coupling technologies for packaging that can easily be scaled for mass production that overcome limitations in the prior art. The inventors have established design methodologies, packaging schemes and component designs that leverage automated passive assembly techniques for speed / cost in combination with directly written optical interconnects that allow for offsetting the losses that would arise from the manufacturing tolerances of these passive assembly techniques.

This invention discloses a photonic terahertz communication system based on non-uniform probabilistic shaping, belonging to the field of terahertz communication. Specifically, it includes a transmitter and a receiver. The transmitter incorporates non-uniform probabilistic shaping and phase fuzzy encryption techniques, using photonic beat frequency generation to produce a terahertz signal. This signal is then transmitted wirelessly via single-mode fiber to the receiver, where it is mixed with a frequency-multiplied local oscillator signal to achieve down-conversion of the terahertz signal, obtaining an intermediate frequency (IF) signal. The IF signal is then sampled and input to an RX-DSP module for digital signal processing, ultimately obtaining the original data and calculating the bit error rate (BER). This invention improves the system's BER performance and significantly enhances the security of the photonic terahertz communication system.

The application discloses a graphene-coated surface saturable absorber device of a multimode optical fiber with an internal microstructure, which adopts a mixed structure of graphene and a graded-index multimode optical fiber. The saturable absorber device comprises a first single-mode optical fiber, a mixed structure based on a multimode optical fiber, and a second single-mode optical fiber. The mixed structure based on the multimode optical fiber is composed of a tapered graded-index multimode optical fiber with an internal microstructure and a single-layer graphene film. The graded-index multimode optical fiber is first subjected to a micro-tapering treatment, then a microstructure is inscribed in the core inside the taper waist, then the graphene film is coated on the surface of the taper waist of the optical fiber, and finally the single-mode optical fibers are fused at both ends of the multimode optical fiber. The saturable absorber combines the nonlinear multimode interference effect in the multimode optical fiber and the saturable absorption characteristics of graphene, can perform secondary compression on the pulse width of a high-energy pulse, and thus obtains an ultrashort pulse. The application has the advantages of a solid structure, strong stability, a high damage threshold and the like, and provides an effective technical means for obtaining a stable ultrashort pulse mode locking.

A surgical robotic system includes a control tower having a first component configured to transmit and receive communication data, a first multimode fiber optic connection, a first single mode fiber optic connection and a first optical bulkhead connector coupled to the multimode fiber optic connection and the single mode fiber optic connection. The system also includes a surgeon console having a display configured to display video data, a second component configured to transmit and receive the communication data, a second multimode fiber optic connection, a second single mode fiber optic connection, a second optical bulkhead connector coupled to the second multimode fiber optic connection and the second single mode fiber optic connection. A main cable coupled to the first and second optical bulkhead connector, which interconnects the control tower and the surgeon console and is configured to transmit video data along with the communication data.

The utility model discloses a kind of double-parameter optical fiber laser sensors based on Sagnac ring cascaded liquid phase filling MZI, belong to optical fiber sensor technical field, by LD pumped laser source (1), wavelength division multiplexer (2), holmium-doped optical fiber (3), optical circulator (4), sensing probe A (5), first coupler (6), sensing probe B (7), second coupler (8), optical spectrum analyzer (9), first single-mode optical fiber (501) polished in side edge, large core diameter hollow optical fiber (502) fills PDMS (503), few-mode optical fiber (504), fiber bragg grating (505), second single-mode optical fiber (506), third single-mode optical fiber (701), first panda polarization maintaining fiber (702), second panda polarization maintaining fiber (703), fourth single-mode optical fiber (704);The utility model can effectively improve the sensitivity of device to temperature by hollow optical fiber filling PDMS;By panda polarization maintaining fiber rotation shaft fusion splicing makes that interference phase difference amplification, spectral line drift is more obvious, so improve the sensitivity of device to temperature;Different reflection peak signals of few-mode optical fiber grating and Sagnac interference spectrum signals can establish sensitivity matrix to realize double-parameter measurement to temperature and strain, with excellent reliability and stability.

The application discloses a single-mode fiber to multi-mode fiber mode converter which comprises a single-mode fiber head assembly, a transmitting end C lens, a birefringent crystal sequence, a receiving end C lens and a multi-mode fiber head assembly arranged coaxially; an air gap is arranged between the light emitting end of the single-mode fiber head assembly and the transmitting end C lens, and an outer envelope tube of the transmitting end collimator is coaxially fixed to the outer circumferential side of the single-mode fiber head assembly and the transmitting end C lens; the single-mode fiber to multi-mode fiber mode converter can stably assemble each optical component and ensure the overall assembly precision by means of the outer envelope tubes of the transmitting end and receiving end collimators and the inner and outer envelope tubes of the crystal group; all the components are packaged by the overall outer envelope tube, the internal optical structure is effectively protected, and the firmness of the device structure is enhanced.

This invention relates to a single-mode optical fiber supporting fiber-to-chip interconnect applications, comprising a core layer and a cladding layer, wherein the core layer R1 has a radius of 4.2–6.2 μm, and Δ n The cladding thickness ranges from 0.25% to 0.4%, and from the inside out, it consists of an inner cladding, a first planarization layer, a first depressed cladding, a second planarization layer, a second depressed cladding, and an outer cladding. The radius of the inner cladding, R2, is 5.6–9 μm, and Δn2 decreases linearly. The radius of the first planarization layer, R3, is 8.1–9.2 μm, and Δn2 decreases linearly. n 3 is -0.05% to 0.05%, the radius of the first indented blanket R4 is 18.8 to 28.4 μm, Δ n 4 is -0.95% to -0.55%, the radius R5 of the second flattening layer is 24.2 to 29.2 μm, Δ n 5 is -0.05% to 0.05%, the radius of the second indented blanket R6 is 35 to 50 μm, Δ n The 6-value is -0.50% to -0.75%, and the outer cladding layer is a pure silica glass layer. This invention has a low cutoff wavelength, a large mode field diameter, and good bending performance in short-distance applications.

This invention belongs to the field of micro / nano fiber fabrication technology. It discloses a vanadium dioxide-based micro / nano fiber temperature sensor and its fabrication method, including the following steps: (1) After removing a portion of the coating layer on the surface of a single-mode fiber, the fiber cladding in the area where the coating layer has been removed is etched or the area where the coating layer has been removed is heated and stretched using a melt stretching method to obtain a micro / nano fiber; (2) Vanadium metal is deposited onto the etched or stretched area of ​​the micro / nano fiber by magnetron sputtering to obtain a vanadium metal film with a nanometer-level thickness; (3) The deposited micro / nano fiber is annealed in an inert atmosphere to transform the vanadium metal film into an M-phase vanadium dioxide film, thereby obtaining a micro / nano fiber temperature sensor. This invention uses a method of magnetron sputtering to deposit a metal film followed by tube furnace annealing to obtain a vanadium dioxide thin film. The vanadium dioxide thin film can be prepared in a controllable manner, and the pure vanadium dioxide M-phase thin film can be prepared stably and repeatedly. Moreover, the thickness of the coating can be selected independently.

This application provides a ring beam shaping system based on multimode fiber mode interferometry, comprising an input unit, a mode conversion unit, and an output unit. The input unit is a single-mode fiber with a first fiber parameter, used to input a Gaussian beam. The mode conversion unit is a multimode fiber with a second fiber parameter, connected to the single-mode fiber via fusion splicing, used to excite and interfere with higher-order modes. The output unit is a ring-core fiber with a third fiber parameter, connected to the mode conversion unit via fusion splicing, used to maintain and output a ring beam distribution. The core diameters of the single-mode fiber, multimode fiber, and ring-core fiber increase progressively, as do the NA values ​​of the single-mode fiber, multimode fiber, and ring-core fiber. This system achieves high-quality ring beam output through a simple, flexible, and efficient all-fiber structure, significantly reducing cost and complexity, improving stability and reliability, and has broad application prospects.

This utility model relates to the field of fusion splicing device technology, specifically a fusion splicing device for single-mode optical fiber. It includes a base, a displacement component located on the top of the base near the left side, and a first conveying component, a cutting component, and a first positioning component arranged sequentially from left to right on the top of the displacement component. A second conveying component is located on the top of the base near the right side, and a second positioning component is located to the left of the second conveying component. A fusion arc generator is located between the second positioning component and the first positioning component. This single-mode optical fiber fusion splicing device provides stable support to the bottom of the single-mode optical fiber through a first arc-shaped guide plate. Combined with the precise downward cutting of the cutter at the rectangular clearance hole, it effectively prevents bending deformation caused by the flexibility of the optical fiber during the cutting process, ensuring a flat cut end face and providing a high-quality mating surface for subsequent fusion splicing, significantly improving fusion splicing reliability.

The application discloses a hollow optical fiber light-heat spectrum gas sensor and a gas concentration detection system thereof, and relates to the technical field of optical fiber gas detection. The first sensor (00) is sequentially connected with a detection light (1), an incident detection light end single-mode optical fiber (2), a to-be-detected gas molecule (3), a Bragg hollow optical fiber (10), a multimode optical fiber (12), an incident pump light end single-mode optical fiber (13) and a pump light (14). The Bragg hollow optical fiber (10) is a hollow optical fiber with four high-refractive Bragg layers doped in a solid cladding. The application adopts a full optical fiber, naturally forms a gas passage in the optical fiber, and does not need to additionally introduce a complex gas interface structure. The sensor has the advantages of fast response speed, good stability, simple manufacturing process, low cost, avoidance of a tedious processing process such as femtosecond laser drilling, and avoidance of a bulky space alignment structure. The application provides a feasible technical path for realizing the application of the optical fiber gas sensor in multiple fields.

The application discloses a kind of double-channel parallel FPI composite optical fiber temperature salt synchronous measurement sensor and method, belong to marine environment monitoring technical field, the sensor includes light source, light path guiding module, sensor probe and spectral detection module;Sensor probe is connected by single-mode optical fiber, mode control optical fiber, side hole optical fiber and single-mode optical fiber in sequence, two micropores are equipped on side hole optical fiber, respectively constitute temperature sensing cavity and salinity sensing cavity;Sensor probe receives optical signal, after mode excitation, transmission to side hole optical fiber, generate multiple interference signals in probe and superimposed to generate composite interference spectrum;Wherein, two sensing cavities are reflected interference modulation to optical signal, so that temperature and salinity modulation component are contained in multiple interference signals;Spectral detection module receives returned composite interference spectrum and resolves, obtains temperature parameter and salinity parameter, by implementation the application, temperature salt cross talk can be effectively inhibited, and the precision of temperature and salinity parameter synchronous measurement under marine environment is improved.

This invention relates to the field of biomedical detection technology and provides a method for glucose detection based on a hollow antiresonant optical fiber using a polylysine and phenylboronic acid composite membrane. The detection method includes a light source, an optical fiber isolator, a first single-mode optical fiber patch cord, a microfluidic device, a hollow antiresonant optical fiber, a second single-mode optical fiber patch cord, a spectrometer, and a computer. The hollow antiresonant optical fiber is fabricated using a stacked drawing and pressure-assisted splicing process. Gold wires are filled within two selected symmetrical small antiresonant tubes, and the outer wall of these tubes is coated with a polylysine and phenylboronic acid composite membrane. The microfluidic device integrates filtration, temperature control, flow rate control, and pressure monitoring functions. When the polylysine and phenylboronic acid composite membrane specifically binds to glucose molecules in the test solution, the refractive index of the composite membrane is changed, further altering the resonance conditions of surface plasmon resonances, ultimately causing a quantitative shift of the loss peak. The spectrometer collects data, and the computer analyzes the glucose concentration. This method features high sensitivity, strong specificity, good anti-interference, good stability, and integration, providing a new solution for glucose detection and meeting the needs of medical testing and health monitoring.

This invention discloses a coupling structure and method for an anti-resonant hollow fiber and a single-mode fiber, belonging to the field of fiber coupling technology. The technical solution is as follows: a coupling structure for an anti-resonant hollow fiber and a single-mode fiber, characterized by comprising a broadband light source, a first single-mode fiber, an anti-resonant hollow fiber, a tapered coreless fiber, a tapered single-mode fiber, a second single-mode fiber, and a spectrometer. The beneficial effect of this invention is that by adjusting the parameters of the tapered coreless fiber, the light emitted from the anti-resonant hollow fiber is focused into the tapered single-mode fiber, thereby achieving mode field diameter matching between the single-mode fiber and the anti-resonant hollow fiber. Simulation and experimental results show that, compared to the traditional coupling of a tapered single-mode fiber and an anti-resonant hollow fiber, fusing a tapered coreless fiber at the tip of the tapered single-mode fiber significantly improves the coupling efficiency.

This invention provides a demodulation method and system for free-space optical communication links based on helical fractional orbital angular momentum. N data streams are loaded onto a Gaussian beam, and at least one modulated beam of helical fractional OAM (Optical Aspect-Oriented Motion) is generated through a spatial optical phase modulation module. After coaxial beam combining, the beam is emitted in free space and imaged onto the demodulation phase modulation module plane via an optical relay imaging system. A conjugate helical phase map is loaded to demodulate the target OAM, and the focusing optics module is adjusted to couple the peak of the target OAM beam into a single-mode fiber, while non-target OAM beams are isolated. After verifying the demodulation isolation, the demodulation phase map is switched to sequentially recover each data stream. This invention achieves hybrid multiplexing of helical fractional and integer OAM, and achieves a mode isolation of ≥5dB through a dual isolation mechanism of phase conjugate demodulation and spatial optimal focusing. This improves fiber coupling efficiency and communication link robustness, significantly expanding the channel capacity and spectral efficiency of free-space optical communication.