382results about How to "Realize simultaneous measurement" patented technology

The invention discloses a video-image-based method for detecting a non-contact vital sign. The method comprises the following steps of: acquiring video images continuously according to a fixed frame frequency, detecting a region of interest (ROI) region automatically, separating a vital sign signal from a multichannel signal separated from the ROI region, extracting the frequency of the vital sign signal and converting the frequency into the vital sign to acquire a detection result. The invention also discloses a video-image-based system for detecting the non-contact vital sign. The method and the system have the advantages of quickness, real time, capacity of realizing continuous monitoring, high robustness, low cost, wide application range and the like.

The related integrated on-line gas detector can continual detect the content of CO, CO2, SO2, NO, NO2, N2O, CH4, HCl, H2S, HF, O2, H2 and Cl2 in smoke gas, kiln gas and furnace gas, which comprises: a sampling probe, a back-blow valve, a pump, a dehydrator, a fine filter, a bypass valve, a check valve, a stable valve, a flowmeter, a gas analysis sensor, a controller, a signal display, a signal output interface, an operation button, a drier, a power, an outdoor case, a sampling pipe, a sample-gas pipe, and a back-blow pipe. This invention has wide application.

The invention relates to a method using three-dimensional mechanics characteristics and tissue specific imaging of blood vessels and plaques for detection. The method is on the basis of a multi-beam focus wave and superfast plane wave alternative transmitting sequence and can also be extended to a line-by-line scan imaging manner; the forms and the functions of the blood vessels and the plaques are evaluated and imaged respectively from the aspects of the radial-direction, circumferential and axial-direction three-dimensional mechanics characteristics, blood vessel wall shear rate, plaque form and tissue characterization, and the like; the new method which is provided for detection of the vulnerable plaques of a carotid artery is regarded as the improvement of the existing method.

The invention discloses a device for measuring spatial motion with six degrees of freedom and a dynamic measuring method. A fixed platform (1) of the measuring device is provided with six Hooke hinges (2), and a moveable platform (10) is arranged above the fixed platform (1). The moveable platform (10) is provided with six ball hinges (9) which are respectively connected with the corresponding six Hooke hinges (2) through branched chains. A revolute joint (6) of each branched chain is provided with a spiral coder (5). The dynamic measuring method comprises the steps of establishing a coordinate system, measuring an angle-time curve of relative motion of upper and lower support rods of the revolute joint (6) by the spiral coders (5), so as to obtain the law of motion with the spatial six degrees of freedom of an object measured by a positive solution of the angle-time curve of the spiral coder (5) and the like. The device and the method not only measure the motion with the six degrees of freedom simultaneously, but also ensures the accuracy of measuring results, and have the characteristics of being good in flexible, strong in adaptation, wide in measuring range, high in accuracy and the like.

The invention discloses an optical fiber disturbance detection method. According to the method, in the measuring process, segmentation frequency scanning is performed, a scattering curve of he same frequency light is used for measuring dynamic disturbance, correlation detection is performed on the distribution curve, obtained through K-set measurement, of the light power of backward Rayleigh scattering light of any point on a sensor fiber along with the frequency and the distribution curve, obtained through first-set measurement, of the light power of backward Rayleigh scattering light of the corresponding point along with the frequency so as to measure quasi-static disturbance, and therefore simultaneous measurement of dynamic disturbance signals and quasi-static disturbance signals is achieved, and the measuring function and application range of a full-distributed type optical fiber sensor are greatly expanded. The invention further discloses an optical fiber disturbance detection device. The device in a measuring system is simple in structure and low in cost, the measuring time is much shorter than the dynamic and quasi-static disturbance measuring time performed by utilizing two sets of systems, and the continuous measurement of dynamic and quasi-static disturbance can be achieved.

The invention relates to a multifunctional integrated type soil body freezing and thawing test system which comprises five parts including a model bearing system, a temperature controlling system, a water replenishing system, an atmospheric environment simulation system and a data acquisition system. Temperatures of an upper temperature controlling plate and a lower temperature controlling plate in a model box are respectively controlled by a cold bath, a fan and a rotatable sprinkler head are arranged at the top of a box body, and thus simulation of atmosphere rainfall and field wind is realized. the water replenishing system is arranged at the bottom of the box body, a soil sample test section is provided with a temperature sensor, a volume unfrozen-water content sensor, a soil water potential sensor, a heat flux sensor, a deformation sensor and the like, which are used for effectively testing physical mechanical factors such as temperature, volume unfrozen-water content, soil water potential, a heat flux and deformation of a soil sample in a freeze-thawing process, thus measurement precision and range are greatly improved. The defect and the deficiency of size effect caused by small size of an existing freezing-thawing test system are overcome. The multifunctional integrated type soil body freezing and thawing test system is simple in structure, easy to operate, accurate in measurement, low in requirement of a working environment condition, and stable to work.

The invention discloses a method for measuring straightness accuracy and positions thereof based on a double frequency interference principle. The measuring method adopts a double frequency optical laser to output laser beams containing cross-line polarized lights which are processed by the light splitting of a common spectroscope and a depolarization dispersion prism, the beam splitting of a Wollaston prism, the reflection of a right-angle prism, and the transmission of the Wollaston prism, the light splitting of a polarization splitting prism, the beat frequency of an analyzer to finally obtain a first-path reference signal and a second-path reference signal. The measuring method utilizes the dichroism and polarization property of optical devices to make up a double light path measurement structure based on the heterodyne interference principle; the simultaneous measurement of the straightness accuracy and the positions thereof is realized by measuring the optical path difference of the double path, thus having measuring accuracy of the nanometer straightness accuracy and the positions thereof. The method is mainly applied in the motion displacement measurement of an accurate work table, the straightness accuracy detection of an accurate guide rail and the like belonging to fields such as super-precision processing technology, micro-photo dynamoelectric systems, integrated circuit chip manufacturing technology, etc.

The invention relates to the field of two-phase / multi-phase flow measurement, aims to realize the non-intrusive and high precision synchronization acquisition of the flow parameters of a liquid film in (outside) a pipeline and temperature field distribution, and is used for the deep study of a liquid film flow characteristic, a heat transfer characteristic and the like. The employed technical scheme is that according to the liquid film temperature field and flow field simultaneous measurement method based on laser induced fluorescence, when a liquid film with dissolved fluorescent dye forms a dynamic liquid film in a pipeline inner / outer wall or a flat panel, a liquid film fluorescence image is taken through a high speed camera, for a same taken fluorescence image, based on a high speed calibration parameter, the geometric feature of the liquid film fluorescence image is accurately extracted, and flow field characteristics comprising a liquid film thickness and a velocity are obtained. At the same time, based on a calibrated temperature-fluorescence intensity calibration curve, laser intensity calibration and a fluorescence intensity extraction method, a liquid film fluorescence image brightness is accurately extracted, and the instantaneous and time averaged temperature field distribution of the liquid film are obtained. The method is mainly applied to a two-phase / multi-phase flow measurement occasion.

The invention relates to a cavity enhanced absorption spectrum device and method for simultaneous measurement of trace gas concentration and aerosol extinction. The LED temperature is controlled by a semiconductor refrigeration chip to ensure the stability of light intensity output. High reflectivity mirrors at both ends of an optical cavity have the same curvature radius and reflectivity greater than 99.9%, and compose a stable optical resonator. Usually, cavity enhanced absorption spectrum measures the light intensity in the cavity with or without gas absorption and the variation curve of the high reflectivity mirrors' lens reflectivity along with the wavelength, and finally the concentration of absorption gas in the cavity can be obtained. The device and the method provided by the invention can realize simultaneous measurement of trace gas concentration and aerosol extinction. The actual measured total absorption coefficient is divided into two parts, one part is a trace gas absorption structure changing rapidly along with the wavelength, and the other part is gas scattering and aerosol extinction coefficient changing slowly along with the wavelength. Nonlinear least-square fitting is carried out on the measured total absorption coefficient to calculate the concentration of the to-be-measured trace gas, and finally the gas absorption structure and gas scattering are deducted from the total absorption coefficient so as to obtain the aerosol extinction coefficient.

The invention discloses an orthogonal polarization optical fiber biological refractive index sensor and a detecting method thereof. The refractive index sensor includes a broadband light source, a polarizer, a polarization controller, a sensor probe and an orthogonal polarization demodulation processing unit which are sequentially connected with one another by optical fibers; the sensor probe includes a microfluidic control chip for control of injection and discharge of a trace biological solution, and tilted optical fiber optical gratings arranged in microfluidic channels of the microfluidic control chip; the orthogonal polarization demodulation processing unit includes an optical fiber polarization beam splitter, a first spectral detector, a second spectral detector and a spectrum differential module; the sensor probe is connected with the input ends of the first spectral detector and the second spectral detector through the optical fiber polarization beam splitter, and the output ends of the first spectral detector and the second spectral detector are connected with the spectrum differential module. The refractive index sensor has the advantages of high measuring precision of the refractive index, and can realize simultaneous measurement of environmental temperatures.

The invention belongs to the technical field of radioactive waste detection, and discloses neutron gamma combined measuring equipment. The neutron gamma combined measuring equipment comprises a gamma detector part, a transmission source part and a neutron measurement device. When the neutron gamma combined measuring equipment is used for measuring materials in waste bin, the neutron measurement device is fixed, the waste bin rotates on a rotating platform, and the transmission source part and the gamma detector part synchronously move in the height direction of the waste bin to realize simultaneous measurement by neutrons and gamma rays in the waste bin. The equipment is easy to operate, and can perform quantitative analysis on the materials in the waste bin.

The invention aims to provide a distributed optical fiber sensing device for simultaneously detecting Brillouin scattering and Raman scattering, which is characterized by comprising a narrow band light source, two optical couplers, a coded pulse optical modulator, an optical amplifier, three optical fibers, three photoelectric detectors, an electric decoder, an optical frequency shifter, an electronic processor, a light polarization controller and a wavelength division multiplexer. The distributed optical fiber sensing device has the advantages that the Brillouin scattering distributed optical fiber sensing and the Raman scattering distributed optical fiber sensing are simultaneously realized in the same device system; the Brillouin scattering is subjected to temperature compensation by the Raman scattering, so that double parameters of the temperature and the strain are simultaneously measured; and due to the utilization of a coding modulation and optical coherent detection technology, the detectable signal-to-noise ratio is improved, the sensing distance is lengthened and the detection accuracy is improved.

The invention relates to an enhanced multi-group photoacoustic spectrum gas sensing device based on a quartz tuning fork and belongs to the field of a photoacoustic spectrum detection technology. According to the invention, the quartz tuning fork with high quality factor is used to replace a traditional broadband microphone so as to broaden the dynamic range and realize miniaturization of the whole gas sensing device. By arranging a fiber-optic amplifier between a light source and an optical fiber coupler, laser output power of the light source is increased. Thus, it is easy to capture a weak photoacoustic signal generated by the quartz tuning fork, and detection sensitivity of the gas sensing device can be enhanced.

The invention discloses a laser radar system for measuring Raman spectra of atmospheric water and fluorescence spectra of aerosols.The system consists of a transmitting unit, an optical receiving and signal detection unit and a control unit.The transmitting unit adopts a seed injected solid laser to output ultraviolet laser with the narrow linewidth of 354.8 nm and guide the ultraviolet laser to the zenith.The optical receiving and signal detection unit collects backward scattering light from atmospheric substances, produces inhabitation superior to 15 orders of magnitude to nearby light of 354.8 nm and distinguishes and records signal light in the spectrum band range of 393.0-424.0 nm at the spectral precision of 0.8 nm.The control unit guarantees the orderly work of the whole radar system.Under the radiation of ultraviolet laser with the wave length of 354.8 nm, the vibrational-rotational Raman spectrum regions of gas-state, liquid-state and solid-state water sequentially correspond to the ranges of 395-409 nm, 396-410 nm and 401-418 nm.The laser radar system can simultaneously record the Raman spectra produced by the three states of water and fluorescence spectra of produced by aerosol particles and achieve simultaneous detection of the atmospheric water, aerosols and other substances.

The invention belongs to the field of precise optical measurement, and relates to a method for measuring inside and outside outline as well as wall thickness of a differential confocal targeting trigger-type hollow sphere and a device therefor. The method utilizes a differential confocal 'optic probe' sensor to collimate the inner and the outer surfaces of the hollow sphere, and the collimation is matched with the rotation of a working platform, so that the measurement for the outlines of the inner and the outer surfaces as well as the wall thickness of the whole hollow sphere can be completed. Meanwhile, pupil filter technique can be used for improving the resolution and the sensitivity of a system. The invention provides the method for measuring the outlines of the inner and the outer surfaces as well as the wall thickness of the hollow sphere in a trigger way by utilizing a zero point of a differential confocal response curve for a first time, so that the problem that the outlines of the inner and the outer surfaces as well as the wall thickness of the hollow sphere can not be measured at the same time. The differential confocal 'optic probe' sensor detects light intensity signals, and has the advantages of high accuracy, strong ambient interference resistance capability, not damaging measured objects, etc.

The invention provides a physiological signal remote monitoring system based on multimodal imaging technique and application thereof; the physiological signal remote monitoring system comprises an integrated imaging module, a hyperspectral imaging module and a control terminal; the hyperspectral imaging module is disposed above the integrated imaging module, and the integrated imaging module and the hyperspectral imaging module are respectively in communication connection with the control terminal. The physiological signal remote monitoring system integrating the 5 imaging modes of hyperspectral mode, visible light mode, near-infrared mode, far-infrared mode and laser bio-speckle mode can provide high-precision extraction and analysis for physiological signals; meanwhile, the physiological signal remote monitoring system allows coordinated data acquisition among multimodal devices and coordinated processing and analysis among data, such that the different application needs such as sleep monitoring and diseased pig screening are met.

The invention discloses a method for quickly measuring the content of phosphorus, lead and zinc in industrial ferrous dust. The method comprises the steps of sample decomposition, setting the instrument analysis parameters of an ICP (Inductively Coupled Plasma) spectrometer, interference correction, making a working curve, and analyzing the content of to-be-measured elements in a measured sample by using an ICP spectral method, wherein the sample decomposition comprises sample pre-decarburizing treatment and sample pressure-microwave digestion. The invention provides a new method for improving the speed and the accuracy in a chemical test of hazardous elements in metallurgical dust.

The invention relates to a three-direction displacement measurement method based on a laser speckle imaging technology. The three-direction displacement measurement method based on the laser speckle imaging technology can achieve synchronous three-direction displacement measurement. According to the technical scheme, the method includes the following steps that firstly, two laser transmitter sets are installed on a reference point, and a laser speckle imaging system is installed on a position I; secondly, light beams are transmitted to an imaging target surface by the laser transmitters and are focused to form a speckle image by an imaging lens, the speckle image is received by an imaging photoelectric device, and the coordinate values of the center points of two speckles relative to the imaging system are found out by a signal processing unit through an image processing algorithm and serve as original values; thirdly, the laser speckle imaging system is moved to a position II, light beams are transmitted to the imaging target surface by the laser transmitters, and the coordinate values of the center points of two speckles relative to the imaging system are found out and serve as test values; fourthly, the test values are compared with the original values, and the horizontal displacement and the vertical displacement are worked out; fifthly, the three-direction displacement of the position II where test points are located relative to the position I is worked out.

The invention discloses a high sensitive biochemical sensor based on a resonance oscillation type micro cantilever beam structure. The biochemical sensor comprises a resonance oscillation chamber, a cantilever beam and a Whist bridge type detection circuit, wherein a micro column structure (3), a liquid storage tank (4) and a liquid leakage hole (5) through which biochemical solution flows are etched at the free end of the cantilever beam; the support end of the cantilever beam is connected with the Whist bridge type detection circuit; the Whist bridge type detection circuit is composed four U-shaped piezoresistance bars (1), three input electrodes (8, 9, 10) and two output electrodes (7, 11); and the four piezoresistance bars (1) are connected with the input electrodes (8, 9, 10) and the output electrodes (7, 11) through a signal transmission line (2). With the adoption of the biochemical sensor, micro biochemical molecules can be sensed with a high sensitivity by detecting the frequency change after an object to be tested is absorbed; biochemical molecules with micromass can be detected; and the biochemical sensor can be widely used in engineering fields such as medicine and chemistry.

The invention discloses a system for measuring loss of an optical resonant cavity based on an optical cavity ring-down method and mainly overcomes the defect that the conventional system cannot measure the loss of a ground mode and a high-order mode simultaneously. The whole measurement system comprises a laser (1), an acousto-optic switch (2), an optical system (3), a resonant cavity fixing device (8), a ring-down light signal measurement device (15) and a main control computer (14); the laser sends a laser beam which enters the resonant cavity to be measured through the acousto-optic switchand the optical system to form resonant light; when the light intensity of the resonant light is greater than the preset turn-off threshold value of the acousto-optic switch, the acousto-optic switchis turned off to ensure that the resonant cavity to be measured generates ring-down light in a plurality of modes; the ring-down light is subjected to photoelectric conversion and analog-to-digital conversion and then is transmitted to the main control computer; and the main control computer fits and calculates the acquired data so as to obtain the loss of a plurality of laser modes. The system has the advantage of measuring the loss of the plurality of laser modes of the optical resonant cavity simultaneously and is suitable for high-efficiency measurement of the loss of the optical resonantcavity.

The invention discloses a large-scale structure three-dimensional dynamic online measurement device and method. Multiple camera sets are employed, and each camera set comprises two cameras having different shooting angles, three-dimensional full field deformation of a large-scale complex structure can be measured, full field deformation conditions can be observed in real time, and a deformation field of each frame of the cameras can be analyzed after testing; through a fitting splicing method applied to a common imaging region of the camera sets, results of the camera sets are integrated to a coordinate system, the quantity of the camera sets can be enhanced according to demands, various types of large-scale structures can be measured, and full field three-dimensional coordinates and deformation fields of the structures can be measured; slit distances of curved structure surfaces are measured through edge detection, characteristic point extraction and pole line fitting, and all the slit distances of the visual field can be simultaneously measured; change of the structure is not required in a measurement process, no contact structure is needed, and deformation fields and the slit distances are processed simultaneously.

The invention discloses a double-arm robot performance measuring method based on multiple laser trackers. The double-arm robot performance measuring method based on the multiple laser trackers comprises the following steps that (1-1) a double-arm robot tool coordinate system is established; (1-2) a coordinate conversion relation between base coordinate systems of the laser trackers and base coordinate systems of mechanical arms is established; (1-3) a public base coordinate system is unified; (1-4) robot performance measurement point planning is performed; (1-5) the laser trackers and an I / O synchronization technology are used for simultaneously measuring a double-arm robot; and (1-6) and data processing is performed, and a test report is generated. The double-arm robot performance measuring method has the characteristics that two arms of the double-arm robot can be simultaneously measured, the linkage characteristics of the two-arm robot can be evaluated, the movement points of the two arms do not need to be aligned in timing sequence, the measurement precision is high, and the test process is simple.

The invention relates to the field of oceanographic parameter monitoring and optical fiber sensing, and in particular refers to a multifunctional marine environment monitoring device based on a distributed optical fiber sensing technology and a method. The device consists of a sea platform, a distributed optical fiber sensing system, a cable winding tray, a cable and an anchor body. According to the invention, distributed, multi-parameter, real-time and reliable marine environment monitoring is realized; the device and the method are applied to the field of marine environment monitoring; temperature, depth and density of seawater of different hydrology levels and sea current velocity can be measured at the same time.

The invention relates to a method for measuring rainfall by pulse illumination optics. According to the method, controllable pulsed light is adopted, the transmission of the controllable pulsed light is consistent with frame synchronizing signals of image video signals, and the pulsed light is transmitted twice at certain time intervals T in each frame of exposure time; actually, each frame of acquired image is acquired by performing double exposure on precipitation particles, the double exposure makes particles appear at two different positions of the same fame of image, and the velocity of the particles is calculated by measuring the distance in which the particles are moved within the time T on each frame of image; the volume of the particles can be calculated according to particle sizes of precipitation particles in a measured clear precipitation particle image, the instantaneous precipitation values can be calculated by combining sampling areas, and the instantaneous rainfall is integrated to acquire gross rainfall; and rain, snow or hail can be identified according to the image of the precipitation particles and parameters such as drop spectrum distribution, velocity and the like. According to the method, particle size and dropping velocity can be simultaneously measured, and the method is extremely economic.

The invention provides a method for measuring contact finger pressure of a disconnecting switch based on an optical fiber Bragg grating sensor, belonging to the technical field of photoelectron measurement. The device comprises an optical fiber Bragg grating displacement sensor, an optical fiber Bragg grating pressure sensor and the disconnecting switch; the optical fiber Bragg grating displacement sensor is fixedly arranged on a contact wall of a static contact of the disconnecting switch; and the optical fiber Bragg grating pressure sensor is fixedly arranged at the outer side of a spring of the disconnecting switch; and a formula in the specification is utilized to realize the accurate measurement of the contact finger pressure of the disconnecting switch. According to the method disclosed by the invention, the difference on temperature and pressure responses by a sensing grating is utilized to simultaneously measure temperature and pressure; and the method has stronger anti-electromagnetic interference capability, realizes online safety monitoring and accurate measurement on the disconnecting switch, and has stronger anti-interference capability.

Disclosed in the invention is a testing apparatus for steam turbine blade with shroud ring and boss lashing wire structures. The testing apparatus comprises a testing rack, a blade root fixing device, two sets of loading devices, a vibration excitation device, and a measurement device. The blade root fixing device is fixed at a base plate of the testing tack. The loading devices are fixed in groove holes of side plates by two loading plate support units; one set of the loading device is used for providing a circumferential torque for the shroud ring of the turbine blade; and the other set of loading device is used for providing a circumferential torque for the boss lashing wire of the turbine blade. The vibration excitation device is fixed at groove holes of the side plates by two exciter support standing plates. And the measurement device is fixed at the testing rack. According to the invention, the testing apparatus can be used for simulating measurement of steam turbine blades that have different lengths and have the shroud ring and boss lashing wire structures on the actual operation condition, thereby laying the foundation of further development of the steam turbine blade with the shroud ring and boss lashing wire structures.

The invention discloses a fiber grating sensing system capable of simultaneously measuring transverse pressure and temperature based on polarization measurement, and belongs to the field of optical fiber sensing. The fiber grating sensing system mainly comprises a tunable laser with high stability, an optical isolator, an optical circulator, a Bragg fiber grating, a polarization-dependent loss tester and a spectrum analyzer. When the fiber grating is subject to the simultaneous action of transverse pressure and temperature, the polarization-dependent loss property of the transmission end obviously changes due to the dual-deflection effect, and the size of the transverse pressure can be demodulated through the measurement of the polarization-dependent loss tester. The reflective light of the fiber grating is inputted to the spectrum analyzer through the optical circulator, and the temperature is measured by analyzing the movement of the center wavelength of the reflective light spectrum. The fiber grating sensing system has the advantages that the dual parameters of the transverse pressure and the temperature can be simultaneously measured, the sensitivity is high, the structure is simple, and the full-light sensing is realized.

The invention discloses a method and an apparatus for simultaneous determination of post-buckling deformation parameters and elastic moduli of an elastomeric material. The method is as follows: a PLC controller controls a linear stepping motor through a driver, a movable supporting baffle plate is pushed by the linear stepping motor so as to allow a sample to undergo post-buckling deformation, a scanner acquires a post-buckling deformation image of the sample and transfers the image to a notebook computer, and image processing analysis software is used to process the sample so as to obtain the skeleton of the post-buckling deformation image; a coordinate of a point at a leftmost end of the sample and a coordinate of a point at a rightmost end of the sample are determined according to the skeleton of the post-buckling deformation image, a coordinate of the midpoint of chord length between the leftmost end point coordinate and the rightmost end point coordinate is calculated, and then flexibility of the midpoint, corners at the ends and elastic moduli are calculated. According to the invention, synchronous determination of the elastic moduli in a pressure bar post-buckling method and the post-buckling deformation parameters of the pressure bar are realized, which enables the processes of determination and calculation of the elastic moduli to be simplified; test operation is simple, determination precision is improved, and miniaturization, intelligentization and automation of the apparatus are realized.

The invention relates to a method and a device for measuring the refractive index and the thickness of an ice layer in an ICF pellet. The device comprises a light source (a laser or an LED), a beam expander, a beam splitter, a first reflector, a second reflector, a pellet to be measured, a wavefront sensor, a lens, a CCD image sensor and a computer. Through the device, an optical path is divided into two paths, and in combination with the two optical paths, the average refractive index of the ice layer is worked out on the basis of the known average thickness of the ice layer; the average thickness of the ice layer is worked out on the basis of the known average refractive index of the ice layer; therefore, the refractive index and the thickness of the ice layer of the pellet are acquired. Through the method and the device, a double-optical path system and a double-optical path method which are based on optical path difference and ray deflection are provided, and simultaneous measurement of the refractive index and the thickness of the ice layer of the ICF pellet is achieved; fast and non-contact measurement can be achieved, and the measurement accuracy is high; the refractive index distribution of the ice layer of the pellet can be acquired.