58results about How to "High measurement sensitivity" patented technology

The invention discloses a Rydberg atom microwave measurement sensitivity improving method based on atom velocity selection, and relates to the field of Rydberg atom microwave measurement, and the method comprises the steps: moving the frequency of probe light to an energy level resonance transition position of cesium atoms from a ground state to an excited state, scanning the frequency of the coupled light within a Rydberg state energy level preset range, and observing an EIT signal; the frequency of the detection light is changed, the detuning amount of the detection light is selected to enable the EIT signal to reach the maximum, and the frequency of the detection light is locked to the frequency corresponding to the maximum position of the EIT signal; meanwhile, a local oscillation field signal generator in the Rydberg atomic microwave sensitivity measurement device is turned on, and corresponding EIT-AT splitting is generated; the frequency of the coupling light is locked to the coupling light laser frequency corresponding to the lowest point of EIT-AT splitting, and the Rydberg atom microwave measurement sensitivity reaches the maximum. The cesium atom speed is screened and controlled, and the signal-to-noise ratio of the measurement signal is improved, so that the measurement sensitivity is improved.

The invention discloses a laser triangular displacement measuring method and device adopting a multi-view metasurface. Firstly, a transmitting mirror group, a receiving mirror group and an optical filter in a traditional laser triangular displacement sensor are integrated into an integrated multi-view metasurface module based on the metasurface technology, and the module can simultaneously achieve the effects of collimation of emergent laser, imaging of scattered light spots on a target measured object and filtering of stray light of non-working wavelength in the environment; the system has extremely high function integration level, and meanwhile, the complexity of the system is also reduced. A target measured object is scanned by building a displacement calibration experiment platform, the mapping relation between the displacement of the target measured object and the position of an equivalent light spot is obtained, and laser triangular displacement measurement is achieved. The laser triangular displacement measuring device is simple in system composition, easy to assemble and compact and small in whole, can be easily integrated on a moving device to achieve high-precision scanning, and is not prone to mechanical interference.

The invention relates to a broadband electromagnetic current transformer suitable for a 10kV power distribution network intelligent fusion complete switch and a performance detection method of the broadband electromagnetic current transformer. The broadband electromagnetic current transformer comprises a primary side current transformer and a secondary side current transformer, the primary side current transformer comprises a shielding shell, an outgoing line and a magnetic core arranged in the shielding shell; the magnetic core comprises a framework, a metal ring belt and an enameled wire; an annular groove is formed in the shielding shell, and an annular cutting gap communicated with the annular groove is formed in the circumferential wall of the inner ring of the shielding shell; the secondary side current transformer comprises a first reference layer, a second signal layer, a third signal layer and a fourth reference layer; high-frequency transient information generated in the fault process can be effectively collected, the bandwidth range, the measurement precision and the sensitivity of the transformer are improved, the secondary side current transformer adopts a four-layer PCB design, and double constraints of high-frequency signal transmission on a winding in a traditional Rogowski coil are overcome. According to the performance detection method, any field actual waveform can be simulated and output for sensor performance test so as to control the factory performance of a switch.

The present invention relates to the field of optical detection, and in particular to a spectral confocal displacement measurement system based on heterodyne interference and a measurement method thereof, wherein a tunable laser emits monochromatic light of different wavelengths, which is divided into two beams of illumination light by a first beam splitter, one beam of illumination light is incident on a beam combiner after being modulated by a first acousto-optic frequency shifter, and the other beam of illumination light is incident on a beam combiner after being modulated by a second acousto-optic frequency shifter, and the two beams of illumination light after being modulated are combined by the beam combiner and incident on a sample through transmission of a second beam splitter and focusing of an objective lens to generate heterodyne interference, forming two light spots with overlapping areas on the sample; the sample reflects the incident light beam, and the reflected light beam is then sequentially transmitted by an objective lens, reflected by a second beam splitter, focused by a third focusing lens, and suppressed by stray light of a third pinhole, and received by a photodetector, and converted into an electrical signal and transmitted to a processor. The present invention can realize the combination of heterodyne interference technology and spectral confocal microscopy technology, and improve the measurement resolution.

This invention discloses an insulating encapsulation structure and connection method for a probe temperature sensor, relating to the field of temperature sensor technology. The insulating connection bracket has an outer insulating and thermally conductive protective layer, and contains insulating adhesive and a temperature-sensing component. The specific implementation is as follows: an insulating layer assembly, a built-in snap-fit ​​structure within the insulating connection bracket, and an eccentric cavity for housing the temperature-sensing component. A thermistor glass body is used as the insulator. In the insulation process, direct contact between the glass body and the inner wall of the bracket reduces one useless insulating layer. The cavity formed by the end of the insulating connection bracket and the insulating layer assembly houses the temperature-sensing component. The cavity contains a clearance structure for the thermistor pins and multiple layers of insulation between the pins and the conductive copper wires. A fluid insulating adhesive is used, and then the insulating connection is cured. Finally, the encapsulation is placed inside a metal shell containing insulating adhesive and cured, thus forming multiple layers of effective insulation and sufficient safe insulation thickness between the thermistor conductive pins and the metal shell.

The invention provides a digital heterodyne interference demodulation technology based on a chaotic signal enhancement array. An all-optical random code optical path module, a heterodyne interference optical path module, a sensing array module and a data processing module are included. The all-optical random code optical path module is composed of a polarization controller (PC), an electro-optical modulator (EOM), an erbium-doped optical fiber amplifier (EDFA), a highly nonlinear optical fiber (HNLF), a band-pass filter (BPF) and a first optical fiber coupler which are sequentially connected through optical fibers, wherein EOM electric control signals are connected through a chaotic entropy source. The heterodyne interference light path module is composed of a single-frequency laser, a second optical fiber coupler, an upper interference arm, a lower interference arm, an optical fiber circulator, an acoustic optical modulator (AOM) and a third optical fiber coupler; the sensor array module is composed of a plurality of optical fiber weak reflection points (FWR) and optical fiber sensors connected between the FWR and the FWR. The data processing module is composed of a photoelectric detector (PD), a plurality of delay units, a plurality of multipliers, a phase demodulator and a computer. The method has the advantages that on the basis of a traditional digital heterodyne interference demodulation method, a chaotic entropy source all-optical true random code is introduced to serve as a digital modulation signal, and the spatial resolution of a demodulation system can be improved to the magnitude of cm as high as 10 Gb / s; the infinite code length effect of the all-optical random code in the chaotic signal enhanced heterodyne interference breaks through the signal-to-noise ratio limit of the traditional digital enhanced heterodyne interference method.

The utility model relates to the technical field of coal slime water treatment, in particular to a coal slime water solid content detection device which comprises a supporting frame, and an ore pulp constant volume device is placed on the supporting frame. Lifting weighing parts are arranged at the bottom of the ore pulp constant volume container at intervals, and the weighing ends of the lifting weighing parts can jack the ore pulp constant volume container away from the supporting frame from bottom to top and weigh the ore pulp constant volume container. According to the utility model, the mass of solid matters in the slime water pulp can be accurately calculated, so that the accuracy of slime water pulp concentration calculation is improved.

The application aims to provide a biaxial anisotropic material dielectric constant temperature variation test system and method, and belongs to the technical field of microwave and millimeter wave test. The system innovatively designs a free space terminal short circuit test system, realizes the acquisition of S21 parameters of microwave materials under high temperature through symmetrically arranging two antennas, and inversely obtains electromagnetic parameters based on the S21 parameters. Meanwhile, the test system can rotate the sample and rotate the antenna by 90 degrees, so as to realize the extraction of electromagnetic parameters of isotropic materials and biaxial anisotropic materials under high temperature in a wide frequency band, and has the advantages of large test range, simple detection mode, high measurement precision and the like.

The present invention provides a detection system for early tumor screening and its application in the preparation of tumor antigen detection products, belonging to the technical field of early tumor screening. The present invention provides the application of a micro-pot array chip combined with micron-sized magnetic beads in the preparation of an ELISA detection product for early tumor screening. The present invention uses micron-sized hydrophilic micro-pots as reaction carriers for ELISA detection, and uses micron-sized magnetic beads to encapsulate capture antibodies used to capture tumor antigens. By limiting the fluorescent groups produced by a single enzyme-catalyzed substrate to an extremely small volume, a high local concentration of fluorescent product molecules is ensured to generate a sufficiently strong optical signal to be detected, thereby realizing the detection of extremely low concentrations of tumor antigens. At the same time, the present invention can reduce the amount of sample collection, such as the amount of blood collection, and the amount of serum required for detection can be achieved by drawing blood from the fingertips, greatly reducing the degree of trauma to the patient.

The application discloses a multi-signal detection device based on quantum entanglement and joint measurement, comprising a laser, an optical parametric amplifier group, a signal loading module group, a beam splitter network group and a balanced homodyne detection device group arranged in sequence along an optical path. The device adopts a modular optical structure design, and through the synergistic effect of compressed light source, entangled state preparation, interference measurement and joint detection, realizes the function of quantum enhanced measurement. The application also discloses a method for multi-signal detection by using the device, and through the introduction of quantum entanglement resources and the combination of joint measurement mechanism, the sensitivity of multi-parameter measurement is significantly improved. The measurement precision of multiple parameters to be estimated can all break through the standard quantum limit, and reach the quantum Cramer-Rao bound of the system; meanwhile, the estimation precision of each parameter presents good consistency.

The application discloses a kind of high-sensitivity magnetic field detection device and method, device includes sequentially arranged in light propagation direction narrow line width tunable light source, polarized light formation module, first convex lens, second convex lens, Fabry-Perot cavity and detection calculation module, the Fabry-Perot cavity is equipped with the magneto-optical crystal that circled magnetic field coil, wherein, narrow line width tunable light source emits elliptically polarized signal light, polarized light formation module is formed into linearly polarized light of preset angle by signal light, Fabry-Perot cavity is formed with the linearly polarized light of resonance by injection, and linearly polarized light is shot from the cavity after being incident with two modes of light beam after magneto-optical crystal, detection calculation module includes connected detection unit and calculation unit, detection unit receives two modes of light beam, and calculation unit calculates the magnetic field applied to magneto-optical crystal according to the frequency difference of two modes.The application simple structure, simple operation, wide use, high sensitivity.

The invention discloses a strong pumping bilateral resonance modulation-demodulation magnetic sensitivity enhancement method of a quantum magnetic compass. The method comprises the following steps: constructing a quantum magnetic compass platform comprising a sensing unit and external optical and microelectronic devices; quantum state enhanced reading containing magnetic vector information is realized by using a pumping enhancement mode; a standard diamond is used, the thermal conductivity and the light transmission of the diamond are utilized, the initialization of a quantum state is realized by using near-saturation external pump light, the line width is narrowed, and the magnetic measurement sensitivity is improved; noise in the environment is filtered out in a modulation and demodulation mode, and high-robustness extraction of quantum information is achieved. By enhancing the laser pumping power, the emission speed of the solid-state quantum color center ensemble fluorescence photons is increased, the full width at half maximum of a magnetic resonance curve is compressed, and the measuring capacity of the solid-state quantum color center to a magnetic field is improved; accurate measurement of external magnetic field signals through the solid quantum color center in the diamond is realized.

The present application relates to shear stress detection technical field, especially to a kind of stress detection device, comprising: first mechanical arm, second mechanical arm, detection component and power component, its first mechanical arm and second mechanical arm are respectively with same rotational speed along opposite rotating directions movement, to the part to be measured is applied a pair of equal, opposite force moment, to twist the part to be measured;Detection component is used to detect the torque generated by the part to be measured twisted by first mechanical arm and second mechanical arm.This application is by first mechanical arm and second mechanical arm with same rotational speed, opposite direction to part exert torque load, while with the flexible detection band and the strain matrix on it that adhere to the surface of part, real-time acquisition and processing the multidimensional torsional stress generated by part surface in the process of twisting, realize the directional, real-time detection of torsional stress.

This invention provides an IGBT device. A temperature sensor is integrated on one side of the cell region within the IGBT device to monitor the device's actual temperature in real time. Multiple diodes are connected in series within the temperature sensor to amplify the temperature sensing signal, improving measurement accuracy and sensitivity, and enhancing the anti-interference capability of the temperature sensing. Each diode is located on the field oxide layer to achieve electrical isolation. Furthermore, the field oxide layer has a specific size to prevent high-voltage breakdown and enhance device reliability. Each diode also has an N-type doped region and a P-type doped region; the N-type and P-type doped regions are respectively connected to metal plugs for electrode leads. Furthermore, the metal plugs are of a specific size to reduce contact resistance and further enhance device performance.

The application discloses a device and method for measuring fluorescence quantum yield of two-dimensional transition metal chalcogenide compound material, and belongs to the technical field of optical measurement and material characterization. The method comprises the following steps: calibrating a system response function about wavelength; measuring the absorption rate of the two-dimensional transition metal chalcogenide compound material to incident laser; measuring the photoluminescence spectrum of the two-dimensional transition metal chalcogenide compound material; measuring the integral intensity of the diffuse reflection spectrum under the same condition by using a diffuse reflection mirror; and calculating the fluorescence quantum yield of the two-dimensional transition metal chalcogenide compound material according to the system response function, the absorption rate of the two-dimensional transition metal chalcogenide compound material to incident laser, the photoluminescence spectrum of the two-dimensional transition metal chalcogenide compound material and the integral intensity of the diffuse reflection spectrum. The fluorescence quantum yield of the two-dimensional transition metal chalcogenide compound material can be accurately measured, so that the quantitative, rapid and non-destructive characterization of the light-emitting efficiency of the two-dimensional transition metal chalcogenide compound material is realized.

The present application proposes a wide-band phase object, a 4f optical nonlinear measurement system and a measurement method. The phase object uses two glass slides to overlap to produce a gap to meet the basic requirements for making a phase object, and is made into an ordinary phase object and an absorptive phase object, which is placed on a rotating platform. The thickness of the phase object is controlled by adjusting the rotation angle of the rotating platform to achieve the control of the phase of the phase object. When the phase produced by the phase object is an integer multiple of π / 2, complete interference bright or dark lines will appear on the central liquid film or film, and the nonlinear refraction phenomenon of the sample to be measured can be clearly observed, and the optimal sensitivity can be achieved at this time. Another use of fixing the phase object on the rotating platform is that the thickness of the phase object can be freely and accurately controlled. Under continuous wavelength waves, the appropriate thickness at the corresponding wavelength can be found by adjusting the rotation angle of the rotating platform to achieve the optimal measurement sensitivity.

The invention discloses an interference type all-fiber flow velocity sensor and a manufacturing method thereof, the interference type all-fiber flow velocity sensor comprises a silica fiber, a hollow fiber, a transmission fiber, a shell, an armoring structure and a fiber connector, two ends of the hollow fiber are respectively welded with the silica fiber and the transmission fiber to form a Fabry-Perot cavity for sensing fluid flow velocity, and the Fabry-Perot cavity is marked as a measurement area; the housing is sleeved outside a sensitive assembly composed of the silica fiber, the hollow fiber and the transmission fiber, and is provided with a window for a measurement area. The non-welding end of the transmission optical fiber extends out of the shell, penetrates through the armored structure and then is connected with an optical fiber connector; the optical fiber connector is connected with a demodulation device, and transmits the interference signal to the demodulation device for resolving. The method is simple in process, low in manufacturing cost and high in measurement sensitivity, and is an optimal measurement method for engineering application.

The invention discloses a relaxation fluctuation suppression method influenced by temperature change of an optical pump atom magnetometer, and the method comprises the following steps: constructing a relaxation noise model influenced by temperature based on the optical pump atom magnetometer, the relaxation noise model comprising a mapping relation between a measurement error of the optical pump atom magnetometer and a gas chamber temperature of an environment where the relaxation noise model is located; based on the mapping relation and the heat transfer principle, an air chamber heating thermal model is constructed, and the air chamber heating thermal model describes the dynamic relation between the heating film input voltage and the air chamber temperature; updating parameters of the air chamber heating thermal model in real time by applying a self-adaptive model predictive control algorithm; on the basis of the updated thermal model parameters, model predictive control algorithm control is executed so as to restrain air chamber temperature fluctuation, and then relaxation fluctuation of atoms in the optical pump atom magnetometer is restrained; the establishment time and overshoot of air chamber heating are effectively reduced, the low-frequency noise level of the optical pump atom magnetometer is reduced, and the measurement sensitivity is improved.

The utility model discloses a multi-point detection fiber bragg grating sensor for soil moisture content. The multi-point detection fiber bragg grating sensor comprises an optical fiber protection tube and a measuring tube assembly, one end of the optical fiber protection tube is connected with the head end of the measuring tube assembly; the measuring pipe assembly comprises a plurality of measuring pipes, and every two adjacent measuring pipes are connected through a heat insulation pipe. Densely distributed optical fibers are arranged in the measuring tube assembly, and optical fiber grating regions are arranged at the positions, corresponding to the measuring tubes, of the densely distributed optical fibers respectively; a heating resistance wire is arranged in each measuring tube; and densely distributed optical fibers led out from the measuring tube assembly and a lead connected with the heating resistance wire are fixed in the optical fiber protection tube. The soil moisture detector can be inserted into soil to detect the moisture content of different positions of the soil at one time, the detected soil cannot be damaged, the measurement precision is high, and the detection process is convenient and fast.

The invention discloses a Raman grating magneto-optical trap gravimeter realized by pulse laser. The Raman grating magneto-optical trap gravimeter comprises a central controller, a coherent laser generator and a grating magneto-optical trap gravimeter, the central controller controls the coherent laser generator and is used for outputting control voltage so as to control operation of the seed light laser, the optical fiber electro-optical modulator, the pulse laser generator, the multi-stage optical fiber amplifier and the optical fiber acousto-optic modulator. The seed light laser outputs continuous laser to be injected into the optical fiber electro-optical modulator; the optical fiber electro-optical modulator adopts a radio frequency signal to modulate input continuous laser and then injects the continuous laser into the pulse laser generator; the pulse laser generator continuously converts laser into short-pulse laser and injects the short-pulse laser into the multi-stage optical fiber amplifier; a frequency doubling crystal after short pulse laser amplification; frequency is increased and converted into the required laser wavelength, the laser wavelength is injected into the optical fiber acousto-optic modulator, and the output of the optical fiber acousto-optic modulator is injected into the grating magneto-optical trap gravimeter. The device is simple in structure and low in cost, and the research, development, production and application cost of the device is reduced.

The invention discloses a temperature-drift-resistant high-sensitivity micro-vibration sensor and a measuring circuit thereof. The temperature-drift-resistant high-sensitivity micro-vibration sensor comprises a vibration sensing module and a measuring circuit module, a signal output by the vibration sensing module is conditioned by the measuring circuit module and then enters the data acquisition device; by adopting the two-stage piezoelectric bimorph design for the sensor, the two-stage piezoelectric bimorph can be connected in series to increase the sensitive area of a piezoelectric material under the condition of the same central mass, so that the measurement sensitivity of the sensor is improved, and the contradiction between the high sensitivity and the high-frequency measurement performance of the sensor is solved; by adopting the piezoelectric bimorph design and the precise differential amplification design for the output signal of the piezoelectric bimorph in the measurement circuit, the influence of the temperature effect of the piezoelectric material on the low-frequency measurement performance of the sensor can be avoided. And finally, high-precision measurement of micro vibration in a broadband range is realized.

The invention provides an optical microcavity dispersion measurement method based on dispersion linetype real-time calibration, which is applied to the technical field of microcavity dispersion measurement, and comprises the following steps: converting the position extraction of an optical sideband into the position extraction of a dispersion linetype, and demodulating the optical sideband through a frequency mixer to obtain a sideband harmonic peak of a specific dispersion linetype; adjusting the phase difference between a modulation signal and a demodulation signal of the high-stability radio frequency source, identifying the position of a dispersion line type sideband harmonic peak, and extracting the frequency interval of the sideband harmonic peaks on the two sides of each resonance mode; dynamically calibrating the optical fiber Mach-Zehnder interferometer based on the number of sinusoidal signal cycles in the frequency interval of the dispersion line type sideband resonance peaks on the two sides of each resonance mode to obtain a calibrated Mach-Zehnder interferometer; and generating a dispersion measurement result of the optical microcavity according to the calibrated Mach-Zehnder interferometer interference signal. According to the invention, the dispersion measurement precision and the automation level can be improved.

The invention discloses a sample pre-concentration and separation system and method for measuring trace substances in an environmental water body, belongs to the field of detection of trace gas dissolved in a water body, and aims to solve the technical problems of low separation degree and sensitivity of single equipment in the prior art. The device comprises a gas sample introduction module, a sample quantification module, a water sample pretreatment module, a trapping analysis module and a separation detection module. According to the invention, two sets of pre-column and analytical column systems are utilized to realize echelon separation of components with different properties, substances with different separation activities can realize respective effective separation under flow path switching, confusion caused by similar functional groups is effectively avoided, interference is eliminated, and the separation degree and measurement sensitivity of a target object are improved; meanwhile, two sets of detectors are adopted, so that the detection requirements of different sensitivities can be met.

According to the gyroscope, a detection beam in a second direction is adopted to realize vibration in a first direction, the vibration in the first direction is coupled with an angular velocity in a third direction to generate a Coriolis force in the second direction, and the detection beam is directly connected with a driving beam, so that the Coriolis force can be directly acted on the detection beam by the beam; the attenuation in the transmission process is greatly reduced, the detection sensitivity is remarkably improved, and the overall performance is optimized.

The present invention relates to the technical field of servo motor position detection, and in particular to a servo motor and a servo motor position detection method. The method comprises: installing a choke ring, a multi-pole magnetic ring, and a circular magnetic sensor detection unit in the motor; applying an AC sinusoidal voltage excitation to the circular magnetic sensor detection unit; sensing the sinusoidal change of the magnetic field through the circular magnetic sensor detection unit, and outputting a standing wave signal; superimposing the standing wave signals output by each circular magnetic sensor detection unit to obtain a traveling wave signal; and detecting the traveling wave signal through a time-grid signal processing system to determine the position of the motor. The present invention can increase the output signal, improve the position detection accuracy and measurement sensitivity of the servo motor; reduce the harmonic components of the output signal, and improve the measurement accuracy; directly add the output electrical signals of each magnetic sensor, thereby avoiding the problem that a multiplier is required in the previous motor position detection method based on the time-grid technology, and the more probes there are, the more complicated the multiplication circuit will be.

A partial discharge intelligent sensing device disclosed by the present invention comprises a longitudinal translation support, a transverse translation support and a sensor shell, a control panel is fixedly arranged on one side of the sensor shell, a mounting support is arranged in the sensor shell, and a cooperative structure is arranged at the upper end of the sensor shell. The invention relates to the technical field of partial discharge sensor equipment. According to the partial discharge intelligent sensing equipment, in the moving process of the sensor shell, the detection coil is located in the sensor shell, and the detection coil and the sensor shell are relatively fixed, so that the moving track of the detection coil is the same as that of the sensor shell, and under the condition that the current at the partial discharge position is not changed, the detection coil is not damaged. In the process that the detection coil gradually moves, the relative position of the detection coil and the discharge position is changed, and when the detection coil gradually gets close to the discharge position, a current position signal detected by the detection coil can be gradually increased, so that the purpose of positioning the discharge position is achieved.

The application discloses a vertically electrostatically driven voltage sensitive element and a preparation method thereof. The method comprises the following steps: composing the voltage sensitive element by a bottom plate module, an electrostatic driving module, an induction measurement module and a supporting module, and arranging the electrostatic driving module, the induction measurement module and the supporting module on the bottom plate module; symmetrically arranging the electrostatic driving module on both sides of the induction measurement module, vertically vibrating the electrostatic driving module according to the electrostatic force, driving the induction measurement module by the electrostatic driving module, and vertically vibrating the induction measurement module to measure the current electric field of the voltage sensitive element; and connecting the supporting module with the induction measurement module to support the induction measurement module to vertically vibrate. The application can improve the measurement sensitivity. The application can be widely applied in the technical field of sensors.

The invention provides equipment and a method for measuring lodging resistance of rice, and relates to the technical field of agricultural machinery. The equipment comprises a vertical supporting rod and an overturning supporting rod hinged to the lower end of the vertical supporting rod, a thrust measuring part is installed at the hinged position, a straw holding assembly and a lower straw shearing assembly are integrated on the thrust measuring part, and a mass measuring part and a power supply battery are arranged on the vertical supporting rod. The method comprises the following steps: measuring internode breaking strength; selecting rice plants and measuring the height; bundling at a position 20cm away from the ground surface; applying a thrust to incline for 45 degrees, and measuring the thrust; after shearing, weighing the weight of the upper part; and calculating a bending moment and a lodging index. According to the scheme, thrust, weight and shearing parameters are synchronously obtained through an integrated structure, the field test efficiency and data accuracy are improved, manual operation errors are reduced, and the method can be used for evaluating the lodging resistance of rice.

The invention discloses a method and device for measuring a polarization extinction ratio signal, and the method comprises the following steps: dividing stable wide-spectrum light emitted by a white light source into two beams, one beam is used as signal light, and the other beam is used as reference light; the signal light reflected by each event point of the to-be-detected distributed polarization-maintaining device is coupled with the reference light passing through the delay line to generate a beat frequency interference signal; obtaining a distance-return loss curve, and determining the position of each event point according to the peak position; changing a delay line scanning range, changing polarization state directions of the signal light through a polarization controller, and performing delay line scanning in each polarization state direction; and finding echo reflection peaks of all fast and slow axes on the multiple groups of curves corresponding to each event point, converting the echo reflection peaks into return loss values of the fast and slow axes of the corresponding event point, calculating the maximum difference value of the return loss values of the fast and slow axes, and calculating the actual extinction ratio of the corresponding event point according to the extinction ratio definition. The method is simple and high in measurement precision.

A kind of deep sea high-precision high-pressure temperature control triaxial test device, including pressure chamber for placing soil sample, confining pressure loading mechanism and counter pressure loading mechanism, the confining pressure loading mechanism is used to apply pressure to the soil sample in the pressure chamber, the counter pressure loading mechanism is used to inject water into the soil sample pore in the pressure chamber, the pressure range of the confining pressure and pore pressure that soil sample in the pressure chamber is subjected to is 20-60MPa, the pressure chamber is connected with confining pressure pipeline and counter pressure pipeline, the pressure difference between the confining pressure pipeline and counter pressure pipeline is the effective stress of soil.The beneficial effects of the present application are: by measuring the pressure difference between confining pressure and counter pressure, the effective stress of soil is directly obtained, the traditional way of measuring confining pressure and pore pressure respectively and then calculating effective stress by formula is abandoned, thereby eliminating the error superposition problem caused by large-range sensor measurement respectively.