75 results about "Fiber optic coupler" patented technology

A system and method for locking laser frequency based on a hollow fiber FP resonant cavity are characterized in that the output end of a laser is connected with the first port of an optical fiber circulator, the second port of the optical fiber circulator is connected with the input end of an optical fiber coupler, and the first output end of the optical fiber coupler is connected with the input end of a polarization controller; a second output end of the optical fiber coupler is connected with an input end of the optical trap, an output end of the polarization controller is connected with an input end of the hollow-core optical fiber Fabry-Perot resonant cavity, and an output end of the hollow-core optical fiber Fabry-Perot resonant cavity is connected with a third port of the optical fiber circulator; the second output end of the optical fiber coupler is connected with the input end of the optical trap, the second output end of the optical fiber coupler is aligned with the input end of the optical trap, and optical signals output by the second output end of the optical fiber coupler directly enter the optical trap. The system is simple in structure, low in implementation cost, wide in locking range, high in anti-interference capability and high in integration degree.

Quantum teleportation is essential for many quantum information technologies, including long-distance quantum networks. Using fiber-coupled devices, including state-of-the-art low-noise superconducting nanowire single-photon detectors and off-the-shelf optics, we achieve conditional quantum teleportation of time-bin qubits at the telecommunication wavelength of 1536.5 nm. We measure teleportation fidelities of ≥9% that are consistent with an analytical model of our system, which includes realistic imperfections. To demonstrate the compatibility of our setup with deployed quantum networks, we teleport qubits over 22 km of single-mode fiber while transmitting qubits over an additional 22 km of fiber. Our systems, which are compatible with emerging solid-state quantum devices, provide a realistic foundation for a high-fidelity quantum Internet with practical devices.

The invention discloses a laser Doppler heterodyne noninvasive blood glucose concentration measuring device and method, and belongs to the technical field of medical detection. Comprising a laser generating module which comprises a laser, and a first 1 / 2 wave plate and a polarization splitting prism which are sequentially connected with the laser; and the interference light path module is connected to the two sides of the polarization splitting prism respectively and comprises a first optical fiber coupler connected with the polarization splitting prism, and a second 1 / 2 wave plate and a second optical fiber coupler which are sequentially connected with the other side of the polarization splitting prism. The device has the advantages that noninvasive detection can be achieved, blood sampling wounds are avoided, and the comfort level of a patient is improved; the measurement precision is high, and the blood glucose value can be quickly and accurately obtained by using heterodyne interference and frequency shift technologies.

The invention discloses a fiber-optic gyroscope interference light path device for improving reciprocity. The fiber-optic gyroscope interference light path device comprises a light path part and a circuit part, wherein the light path part is connected with the circuit part; the light path part comprises a light source, an optical fiber coupler and an interference light path; wherein the interference light path comprises a Y waveguide, an optical fiber ring and a detector; the light source is connected with the optical fiber coupler through an optical fiber; the optical fiber coupler is connected with the Y waveguide through an optical fiber; the Y waveguide is connected with the optical fiber ring through an optical fiber; the optical fiber coupler is connected with the detector through an optical fiber; the light source and the detector are both connected with the circuit part. According to the invention, the reciprocity is improved, and the full-temperature zero-bias stability qualification rate after compensation of the fiber-optic gyroscope product is realized.

The invention provides a self-calibration high-strength optical fiber hydrophone based on an end face reflection principle, and relates to the technical field of hydrophones. Comprising the steps that a laser light source emits a first laser beam, and an optical fiber isolator suppresses reflection and outputs a second laser beam. And the optical fiber variable optical attenuator adjusts the incident power and outputs a third laser beam. The 1 * 2 optical fiber coupler splits the laser beam into a fourth laser beam and a fifth laser beam, and the first photoelectric detector monitors power. The optical fiber circulator transmits the fifth laser beam to the optical fiber sensing module, generates reflected light and transmits the reflected light to the second photoelectric detector, and the second photoelectric detector converts the reflected light into a voltage signal. The data acquisition card acquires the signals, the signal demodulation processing unit calculates sound pressure sensitivity according to a mapping relation formula of the voltage signals and sound pressure, and the standard voltage module provides standard voltage for the data acquisition card. The problem that in the prior art, a high-strength hydrophone cannot be repeatedly used and cannot be self-calibrated after being damaged is solved.

The present invention discloses a low-loss and low-power compact heterodyne acousto-optic modulation module. The 0th-order light output by the first fiber acousto-optic modulator is used as the incident light to connect to the output light position of the 1st-order diffracted light of the second fiber acousto-optic modulator; the 1st-order diffracted light output by the first fiber acousto-optic modulator is used as the incident light to connect to the output light position of the 0th-order light of the second fiber acousto-optic modulator; the incident light position of the second fiber acousto-optic modulator is used as the output light position to output the outgoing light; the two-stage fiber acousto-optic modulators adopt the same drive circuit and the radio frequency signals work alternately. The drive circuit of the present invention adopts a scheme of external clock input, homologous dual channels, adjustable dual-channel delay, and timing control. The present invention does not have a fiber coupler. By controlling the diffraction of the two AOMs relative to the trigger signal to adjust the relative delay between pulses, and controlling the turn-on time of the two AOMs to obtain two pulse signals with different frequencies, it has the advantages of low power consumption, small loss, and arbitrarily adjustable delay.

The present invention discloses an ultra-fine diameter heterogeneous fiber optic hydrophone and its manufacturing process. The hydrophone includes a core shaft, a sensitizing cylindrical shell, and a heterogeneous fiber optic interferometer. A cavity is disposed through the core shaft. Sensitizing cylindrical shells are symmetrically arranged on both sides of the core shaft. A heterogeneous fiber optic interferometer is installed in the cavity of the core shaft. The heterogeneous fiber optic interferometer includes a heterogeneous fiber optic coupler, a reference arm ultra-short fine diameter fiber, and a sensing arm ultra-fine diameter fiber. The heterogeneous fiber optic coupler, the reference arm ultra-short fine diameter fiber, and the reference arm mirror are fixedly arranged flatly in the cavity. The sensing arm ultra-fine diameter fiber is evenly wound around the sensitizing cylindrical shell and its end is connected to a sensing arm mirror. The present invention uses ultra-fine diameter ultra-small mode field fibers and fine diameter small mode field fibers to form a heterogeneous fiber optic interference structure, and the fiber is coiled and packaged in an ultra-fine high-sensitivity structure, realizing the fabrication of an ultra-fine diameter, low optical insertion loss, and high-sensitivity hydrophone, which can be applied to fields such as underwater acoustic target detection, environmental noise measurement, and undersea mineral resource exploration.

The present invention relates to the technical field of fiber optic sensors. Disclosed are a differential vernier effect-based probe, a manufacturing method, and an ocean temperature sensor. In the present invention, a fiber optic cable is connected to a fiber optic coupler / splitter, the fiber optic coupler / splitter being further connected to sensing arm A and sensing arm B; sensing arm A extends into a temperature sensing tube fixed in a quartz tube; sensing arm B extends into the quartz tube; sensing arm B is located outside the temperature sensing tube; reflective film A and reflective film B are fixedly connected to the end of the temperature sensing tube away from the fiber optic coupler / splitter, reflective film A being located inside the temperature sensing tube; a cavity between sensing arm A and reflective film A forms a main scale cavity; reflective film B is located outside the temperature sensing tube, the ends of reflective film B and sensing arm B extending into the quartz tube being arranged opposite to each other; and a cavity between sensing arm B and reflective film B forms a vernier cavity. The probe further comprises an evacuated unit, the evacuated unit being fixed on a sensor base. The sensor probe of the present application can effectively improve the signal-to-noise ratio and sensitivity.

The application discloses a kind of spectrometer performance calibration devices for frequency domain OCT system, include: two groups of calibration light path components, light source drive board and fiber coupler;Two groups of calibration light path components are connected to fiber coupler;Fiber coupler is connected to light source drive board;Calibration light path component includes: six-dimensional adjustment frame, installation lens barrel, corner cube, optical flat, two-dimensional adjustment frame, collimating lens and collimating adjustment frame;Corner cube is installed to installation lens barrel;Installation lens barrel is connected to six-dimensional adjustment frame;Optical flat is installed to two-dimensional adjustment frame;Collimating lens is installed to collimating adjustment frame;Collimating adjustment frame is equipped with fiber connection part;Two-dimensional adjustment frame is between installation lens barrel and collimating adjustment frame.This application's spectrometer performance calibration device for frequency domain OCT system, simple structure can obtain signal-to-noise ratio with depth variation curve and other performance indicators, judge spectrometer assembly and debugging result, improve instrument consistency.

An embodiment of the present invention discloses a fiber optic hydrophone and a manufacturing method thereof, which comprises assembling an inner skeleton and an outer skeleton into one body; fixing a portion of a first fiber reserved section located at a first end of the inner skeleton and a portion of a second fiber reserved section located at a first end of the outer skeleton in parallel with each other in a first fiber paralleling groove, and fixing a portion of the first fiber reserved section located at a second end of the outer skeleton and a portion of the second fiber reserved section located at a second end of the outer skeleton in parallel with each other in a second fiber paralleling groove; making a fiber optic coupler by using the remaining first fiber reserved section and the remaining second fiber reserved section located at the first end of the inner skeleton; passing an end portion of the first fiber optic located at the first end of the inner skeleton and an end portion of the second fiber optic located at a gap between the inner skeleton and the outer skeleton so that the fiber optic coupler is located in the gap and is encapsulated without a metal protective tube, thereby improving the axial symmetry of the fiber optic hydrophone, reducing the difficulty in achieving the acceleration resistance performance of the fiber optic hydrophone, and facilitating the miniaturization of the fiber optic hydrophone.

The invention provides optical fiber optical tweezer fluorescence lifetime detection equipment and a detection method. A light beam emitted by a light source is divided into two paths, two paths of received optical signals are coupled by using a first optical fiber coupler, and the coupled optical signals are transmitted to a connected optical fiber circulator and are transmitted to a displacement control assembly through the optical fiber circulator. The displacement control assembly captures target tiny particles by using one path of light signals, excites the target tiny particles by using the light signals corresponding to the other path of light beams to generate excitation fluorescence signals, and performs photon number detection on the excitation fluorescence signals by using the detection assembly to determine the fluorescence lifetime of the target tiny particles. According to the method, the fluorescence lifetime of the tiny particles can be detected while the tiny particles are flexibly controlled, and the method is simpler, more convenient and more efficient, and is suitable for ultrafast signal detection of a precise large instrument.

The invention discloses a DAS-based liquid medicine oil-water layering identification system and a working method thereof, and belongs to the field of optics-pharmacy crossing. The method is used for accurately identifying the oil-water layering condition in the liquid medicine, and is convenient for scientifically and effectively evaluating the excellence of the liquid medicine. The system comprises a laser source, a first optical fiber coupler, a phase modulator, a first optical fiber circulator, an acousto-optic modulator, a Faraday polarization mirror, an erbium-doped optical fiber amplifier, a second optical fiber circulator, an optical fiber Bragg grating, a third optical fiber circulator, a sensing optical fiber, a liquid container, a piezoelectric transducer, a polarization beam splitter, a polarization controller and a second optical fiber coupler. The system comprises a first optical fiber coupler, a second optical fiber coupler, a third optical fiber coupler, a fourth optical fiber coupler, a first photoelectric balance detector, a second photoelectric balance detector, a data acquisition card, a computer and a radio frequency signal source. According to the invention, the high-resolution DAS is used for measuring the oil-water layering condition of the liquid medicine; meanwhile, the system has the advantages of high response, high sensitivity, high fidelity, high resolution, small size, corrosion resistance and the like.

The utility model provides an infrared optical fiber coupling accessory ATR optical fiber spectrum probe data exchangeable device which comprises an optical fiber coupler IC card annular card reader unit and an ATR optical fiber spectrum probe, the optical fiber coupler IC card annular card reader unit is provided with a card reading chip and a processor which are in signal connection, and the ATR optical fiber spectrum probe comprises an ATR probe. The ATR probe is respectively connected to the light outlet knob handle and the light inlet screwing handle through the optical fiber main body, the IC card is embedded in the light outlet knob handle, the processor reads information of the IC card through the card reading chip and uploads the information to the stone spectrometer host through the power supply and communication connecting line, and the stone spectrometer host judges whether the ATR probe meets the requirement or not according to data. The data exchangeable device for the ATR optical fiber spectrum probe of the infrared optical fiber coupling accessory solves the problem of matching attribution interactive verification of the ATR optical fiber spectrum probe of the optical fiber coupling accessory and an infrared spectrometer.

The application relates to a fiber-optic gyroscope Y waveguide nonlinearity index measuring device, which comprises a light source, a fiber coupler, a measured Y waveguide, a fiber ring, a photoelectric detector, a measurement algorithm operator, a high-linearity voltage signal amplifier, a data collector and an upper computer; wherein the light source, the fiber coupler, the Y waveguide and the fiber ring are sequentially connected; the photoelectric detector is connected with the fiber coupler and the measurement algorithm operator; the high-linearity voltage signal amplifier is connected with the Y waveguide and the measurement algorithm operator respectively; the measurement algorithm operator is connected with the data collector; and the data collector is connected with the upper computer. The application can solve the problems that the Y waveguide nonlinearity index of the fiber-optic gyroscope is difficult to measure and cannot be quantitatively tested, and can effectively evaluate the quantitative relationship between the Y waveguide nonlinearity index and the threshold and scale factor nonlinearity indexes of the gyroscope.

The invention relates to a neutron detector comprising an optical fission chamber having a reflective optical cavity and a detection head coupled to the chamber comprising an optical lens and an optical fiber coupler. Specifically, the invention relates to a neutron detector (1) comprising at least one sealed ionization chamber (2), referred to as OFC (abbreviation of optical fission chamber), each chamber implementing an optical conversion and comprising an optical cavity, the operation of which is based on the optical conversion and which contains, at one of its longitudinal ends, a window and an optical lens as an optical interface, a mirror for reflecting photons away from the window is included at the other end.

The present application relates to a kind of liquid leakage judgment and leakage location positioning system and method, including the broadband light source, spectrum analysis module and fiber coupler respectively connected on optical fiber circulator, fiber coupler is connected multiple groups of liquid leakage monitoring sensor respectively;Liquid leakage monitoring sensor includes at least two groups of fiber collimator arranged horizontally on the same axis, wherein a group of fiber collimator is connected fiber grating, and float is arranged in the direction perpendicular to the axis of two groups of fiber collimator;Broadband light source generates optical signal, and optical signal is sent to fiber collimator by fiber coupler, and the reflection signal generated by fiber grating is acquired by spectrum analysis module;The bottom of float has opening, and the liquid leakage enters the inside of float by opening and pushes it to rise, and the light path between two fiber collimators is shielded, and reflection signal disappears in spectrum analysis module, and the position of liquid leakage monitoring sensor corresponding to disappeared signal is positioned leakage position.

The application relates to the technical field of electro-optical frequency comb generation, and discloses a super-narrow-line-width, wide-band, flexible-repetition-frequency and adjustable electro-optical comb generation system and method, which comprises a pump laser generation branch, a fiber ring cavity, and a frequency shift injection locking branch.The pump laser generation branch comprises a distributed feedback laser, a first polarization controller and a first circulator; the fiber ring cavity comprises a second circulator, a Brillouin gain fiber, a fiber delay line, a fiber coupler, a second polarization controller, an electro-optical modulator, a dispersion compensation fiber, an optical amplifier, a flat filter and an isolator; and the frequency shift injection locking branch comprises a narrow-bandwidth filter, a polarization controller and a frequency shifter.The electro-optical frequency comb generation device of the application has a novel structure, realizes super-narrow-line-width, wide-band, flexible-repetition-frequency and adjustable electro-optical comb output, solves the limitations of narrow bandwidth and wide comb line width of a traditional electro-optical frequency comb generated based on electro-optical modulation, and does not need complex active optoelectronic feedback to maintain stable operation of the system.

The invention discloses an optical fiber coupling device, an optical module and an active cable. The optical fiber coupling device comprises an optical assembly which comprises a first block body, a photoelectric conversion accommodating space arranged at the bottom of the front end of the first block body, and a plurality of optical fiber counter bores which are arranged at the rear end of the first block body and extend towards the front end of the first block body, the reflecting surface is arranged on the first block body and is used for implementing light propagation between the optical fiber counter bore and the photoelectric conversion accommodating space; and the jumper comprises a second block body and a plurality of optical fiber through holes which are formed in the second block body and penetrate through the second block body in the front-back direction. When the front end of the jumper is in butt joint with the rear end of the optical assembly, each optical fiber through hole is opposite to the corresponding optical fiber counter bore. The optical fiber coupling device has lower requirements on processing precision and assembling precision, the manufacturing cost is easy to reduce, the overall size is smaller, and the development requirements of miniaturization and high-density integration of an optical module are easy to meet.

The application relates to the field of power electronic devices, in particular to a full-fiber isolation SiC MOSFET gate driver suitable for super-high voltage and application, which comprises a transmitting side, a fiber group and a receiving side connected in sequence, the transmitting side comprises a constant-current laser driver, a semiconductor fiber-coupled laser, a fiber coupler of an FC joint, a high-speed optical transmitter driver and an optical transmitter, the fiber group comprises quartz power optical fibers and plastic signal optical fibers of the FC joint, and the receiving side comprises a beam expander, a laser cell, a 5V voltage-lifting IC, a 25V voltage-lifting IC, an optical receiver, a non-isolated driving IC and a push-pull current expansion circuit; the application adopts power optical fibers and signal optical fibers to transmit power and signals, has the great advantage that the isolation voltage is theoretically infinitely high, and common-mode interference caused by coupling capacitance is eliminated; meanwhile, the device efficiency is reasonably calculated, high-efficiency voltage-lifting ICs are matched, 0.8W driving power is realized, and the driving power is sufficient to drive a 6.5kV 25A high-voltage SiC MOSFET module to work at a switching frequency of 100kHz or above.

The invention discloses a double-sideband FSI optical fiber measurement system and a double-sideband FSI optical fiber measurement method based on temperature drift self-reference correction, which are used for correcting optical fiber short-time amplification measurement error and long-time optical path drift fluctuation caused by temperature drift. Comprising the following steps: 1) generating a double-sideband sweep frequency optical signal through an MZM; 2) establishing wavelength division multiplexing optical paths of the measurement interferometer and the self-reference interferometer; 3) performing frequency mixing interference on the multiplexing measurement light and the reference light, and acquiring an orthogonal interference signal; 4) resolving a corresponding phase difference of the two interferometers based on a time-shifting Ap-FFT algorithm; 5) constructing a double-sideband FSI dynamic measurement formula, and correcting a short-time temperature drift amplification error; 6, a long-time optical fiber optical path-temperature drift model is established, a temperature drift self-correction formula is derived, and long-time optical fiber temperature drift self-correction.According to the long-time optical fiber temperature drift self-correction method, the effect of complex active temperature control is achieved only by adding two optical fiber couplers, measurement limitation caused by temperature control limit is overcome, the optical fiber measurement precision and stability are remarkably improved, and meanwhile cost expenditure is reduced.

The present invention discloses a detection unit with increased detection length, which is used to extend the detection range of a distributed physical quantity measurement device, and is characterized in that it includes: a fiber optic coupler, wherein the fiber optic coupler includes a main body, which is used to couple the distributed physical quantity remote detection device to introduce detection light into at least a first port of the main body; a second port including a reflective structure to provide reference light to the main body; and a third port for coupling with a sensing fiber to introduce measurement light including information about the measured physical quantity into the main body. The present invention applies a distributed physical quantity detection unit with increased detection length to a distributed physical quantity measurement device based on optical frequency domain reflection technology. The system measurement length is no longer occupied between the measuring host and the measured structure, and the sensing fiber can be arranged far away from the host, which is suitable for measurement occasions where the measuring host and the measured structure are far apart. The present invention also discloses a corresponding distributed measurement device.

A Fabry-Perot sensor cavity length demodulation system and a Fabry-Perot sensor cavity length demodulation method. The demodulation system comprises: a first light source (1) emitting light of a first wavelength; a second light source (2) emitting light of a second wavelength; a wavelength division multiplexer (3) receiving light from the first light source (1) and light from the second light source (2); a fiber coupler (4) receiving and coupling light of the first light source (1) and light of the second light source (2); a Fabry-Perot sensor (5) receiving coupled light from the fiber coupler (4) such that the coupled light is reflected at a first plane and a second plane of the Fabry-Perot sensor (5) to interfere and return the interference light to the fiber coupler (4); a demultiplexer (6) receiving the interference light and separating the interference light into a first light beam (L1) and a second light beam (L2); a first detector (7) and a second detector (8) respectively receiving the first light beam (L1) and the second light beam (L2) and transmitting a first interference signal of the first light beam (L1) and a second interference signal of the second light beam (L2) to a processor (9), the processor (9) being configured to obtain and analyze a first curve (S1) of the first interference signal and a second curve (S2) of the second interference signal to determine an inflection point of a physical quantity to be measured causing a cavity length change in the first curve (S1) and / or the second curve (S2), the first curve (S1) being a curve of light intensity of the first interference signal with respect to the cavity length, and the second curve (S2) being a curve of light intensity of the second interference signal with respect to the cavity length.

Systems disclosed herein are directed to optical terminals configured for free space communication comprising at least one lens collector assembly comprising a lens and a dual clad fiber optic coupler attached to the at least one lens, and a transceiver operably connected to the at least one lens collector assembly.

This invention discloses a small, high-precision fiber optic angular acceleration measurement device. The light source module is connected to a fiber optic circulator via a polarizer, and the fiber optic circulator is connected to an optical modulator via a fiber optic coupler. The optical modulator is connected to a polarization-maintaining fiber optic ring, used to split the linearly polarized light into two counter-propagating beams that enter the polarization-maintaining fiber optic ring, and to receive the interference signal returned from the polarization-maintaining fiber optic ring and input it into the fiber optic coupler. The fiber optic coupler splits the interference signal into two outputs: one path enters a first photodetector via the fiber optic circulator, and the other path enters a second photodetector. The first photodetector converts the received optical signal into an electrical signal and inputs it into a first digital signal acquisition processor. The second photodetector converts the received optical signal into an electrical signal and inputs it into a second digital signal acquisition processor. The first and second digital signal acquisition processors respectively acquire and process the input signals and input them into a data processing unit to calculate the angular acceleration value.

This invention discloses a miniature beam-splitting optical path system for atomic interferometry, comprising a main optical path and primary and secondary reflection sub-paths. Laser light is input into the main optical path after purification and polarization, and then split by a half-wave plate and a polarizing beam-splitting prism. The split beam consists of a primary reflection and a secondary reflection generated by the secondary reflection, which passes sequentially through a quarter-wave plate and a 0° mirror and re-enters the polarizing beam-splitting prism. The primary and secondary reflections then enter their respective sub-paths for further splitting. Independently adjustable right-angle prisms and polarizing beam-splitting prisms within the sub-paths eliminate the influence of the incident direction of the light entering subsequent optical paths. This miniature beam-splitting optical path system and method can output multiple laser beams with consistent polarization, adjustable power and frequency. It can be input and output via fiber optic couplers, and is suitable for atomic interferometry and other fields. It improves the efficiency of laser energy utilization and the stability of laser parameters, easily maintains symmetrical optical path distribution, and enhances system integration.

An OCT online monitoring device for processing transparent and non-transparent composite materials. The present invention relates to the technical field of composite material monitoring, and specifically to the technical field of OCT online monitoring devices for processing transparent and non-transparent composite materials. The present invention first adopts a method of alternately emitting a low-coherence light source and a high-spectral integrated light source to extract the structural information of transparent and non-transparent composite materials, and adopts a dual-path method to simultaneously collect the structural information of transparent and non-transparent composite materials for analysis and processing, thereby improving the comprehensiveness and accuracy of monitoring transparent and non-transparent composite materials. The device comprises: a composite light source, a fiber optic coupler, a reference arm, a sample arm and an imaging processing unit; the fiber optic coupler is respectively connected to the composite light source, the reference arm, the sample arm and the imaging processing unit. The present invention can monitor the microscopic evolution of processing processes such as melting, welding and solidification in real time under non-contact conditions, and provide a high-resolution and dynamic process control basis for composite material molding.

A fiber coupler (135) for coupling a plurality of cores (160) of a multi-core optical fiber (105) to an integrated photonic device comprises a grating array comprising a plurality of polarization splitting gratings (180) arranged in a manner that corresponds to the plurality of cores (160) in the multi-core optical fiber (105). The fiber coupler (135) also comprises first and second mode converters (235, 240) extending from first and second sides of each of the plurality of polarization splitting gratings (180) to receive first and second polarization modes of the optical signal scattered by the polarization splitting grating (180). A plurality of waveguides (145-a, 145-b) extends from ends of each of the mode converters (235, 240) to guide a single polarization mode of one of the optical signals.

This invention discloses an experimental method for measuring the electron-hole recombination emission rate. The apparatus for this method includes a laser chip (with an anti-reflection coating on only one end of its horizontal two-sided end face), a plano-convex lens, a polarizer, a fiber optic coupler, an optical fiber, and a spectrometer. The plano-convex lens, polarizer, plano-convex lens, and fiber optic coupler are placed sequentially on the same horizontal line on both sides of the chip. The fiber optic coupler is connected to the spectrometer via an optical fiber. First, energy is applied to the laser chip, causing it to emit light from both sides. The spectra from both sides are focused onto the fiber optic coupler by the plano-convex lens and then transmitted to the spectrometer via the optical fiber. By rotating the polarizer, different polarization spectra can be selected to obtain specific spectral images under transverse electric / magnetic field modes. Finally, by substituting the spectral data from both ends into the established formula, the electron-hole recombination rate of the laser chip can be calculated.

This invention specifically relates to a refractive index measurement system and method based on fiber optic interferometry, used for real-time monitoring of the refractive index of transparent gases and liquids. It addresses the technical problems of existing air refractive index measurement methods, which either struggle to accurately obtain the absolute value of the refractive index, or involve complex procedures, cumbersome optical path adjustments, susceptibility to vibration interference, and low dynamic response speed. The fiber optic interferometry-based refractive index measurement system includes a tunable fiber laser, a first fiber coupler, a transmitting probe, a receiving probe, an attenuator, a second fiber coupler, a photoelectric converter, and a recording device. The first fiber coupler splits the optical signal emitted from the tunable fiber laser into two paths, one input to the transmitting probe and the other to the attenuator. The input of the second fiber coupler is connected to the output of the attenuator and the output of the receiving probe. This invention offers high reliability and a fast response time of 0.2 ms; it can perform refractive index monitoring in various scenarios.

The application relates to a miniaturized near-infrared spectrometer imaging system, and relates to the field of near-infrared spectrometers, which comprises a light source module, a sample light line generation module, a fiber coupler, a fiber F-P filter, a photodetector and a multimode optical fiber; the light generated by the light source module can irradiate a sample through the sample light line generation module and generate sample light lines; the fiber coupler and the fiber F-P filter are connected through the multimode optical fiber, and the fiber F-P filter and the photodetector are connected through the multimode optical fiber; the fiber coupler receives the sample light fiber and transmits the sample light fiber to the photodetector through the multimode optical fiber, the fiber F-P filter and the multimode optical fiber. The application has the effects of reducing the baseline drift and noise of the spectrum, improving the accuracy of the spectrum, and being smaller in size and lighter in weight.