1999 results about "Optical pathlength" patented technology

The invention discloses a solar cell and a photovoltaic module. Wherein the semiconductor substrate comprises a first surface and a second surface which are opposite to each other, and a side surface connected with the first surface and the second surface; in the direction from the first face to the second face, the side face comprises a first area and a second area which are sequentially arranged, the first area is provided with a first texture structure, and the second area is provided with a second texture structure. The first texture structure and the second texture structure can enable light incident to the side face to be reflected and refracted for multiple times, the advancing direction of the incident light on the side face of the semiconductor substrate is changed, the optical path is prolonged, the light trapping effect is generated, and generation of photon-generated carriers is increased, so that when the side face of the semiconductor substrate is provided with the first texture structure and the second texture structure, the light trapping effect is improved. More light rays can be absorbed and utilized by the side surface of the semiconductor substrate, and the photoelectric conversion efficiency of the solar cell can be improved.

The invention discloses a heat shrink tube detection method based on image recognition, particularly relates to the technical field of electric power material defect detection, and is used for solving the problems of defect contour distortion, positioning deviation and insufficient classification precision caused by optical ghost interference in heat shrink tube detection. A mapping relation of light refraction paths is established based on brightness gradient difference and refractive index difference, theoretical ghost interference fringes are generated by dynamically adjusting optical path difference of an interferometer, and abnormal areas deviating from theoretical distribution are screened; meanwhile, light source incident angle optimization and defect displacement calculation are combined, residual ghost interference is eliminated, finally, accurate classification and positioning of defects are achieved through multi-dimensional matching of geometric parameters and historical defect data, complex algorithm dependence is reduced while the detection precision is improved, and the real-time detection requirement of an industrial production line is met.

The invention discloses a vehicle-mounted holder laser telemetering scanning type gas leakage positioning system, and relates to the technical field of gas leakage monitoring. The vehicle-mounted pan-tilt laser telemetering scanning type gas leakage positioning system comprises a data acquisition unit for acquiring laser absorption second harmonic signal intensity of an inspection vehicle on a set route; the concentration inversion processing unit is used for inverting the gas concentration on the basis of the signal; the concentration analysis unit is used for identifying an abnormal inspection point by comparing the concentration change rate; the leakage direction analysis unit is used for predicting the leakage direction by combining wind direction concentration data; according to the invention, a signal saturation upper limit value and an optical path length value are introduced to carry out normalization processing, concentration inversion calibration is carried out in combination with a gas absorption coefficient, independent calculation is carried out at each inspection position point, and the accuracy of the inspection is greatly improved by combining remote measurement concentration distribution data, image data and a leakage position analysis unit for accurately positioning a leakage point in combination with a gas diffusion model. And continuous, dynamic and high-precision concentration distribution reconstruction in space is realized.

The invention discloses a detection and analysis system for an oil-controlling and soothing extract, particularly relates to the field of extract detection, is used for solving the problem of accurate quantitative analysis of complex components, and is characterized in that omnibearing characteristics of a sample are synchronously acquired and captured through multiple spectrums, and the information is fused into a high-dimensional data framework, so that the limitation of a single spectrum is avoided; thirdly, noise is removed through accurate calibration, sparse decomposition and cross-modal verification are combined, and it is ensured that extracted component signals truly reflect chemical characteristics and are not covered by redundant interference; on the basis, a clear signal of a target active component is further separated by utilizing dynamic convolution and an attention mechanism, and irrelevant background influence is eliminated; finally, through segmented modeling and geometric constraint, absorbance change is accurately converted into concentration data, and the concentration data can be kept stable even under the background fluctuation or nonlinear condition, so that the quantitative inversion error of the active component is reduced under the scene of background signal fluctuation or non-uniform optical path, and the accuracy of a determination result is improved.

The invention relates to the cross technical field of atmospheric science and communication technology, in particular to an atmospheric refraction and waveguide environmental parameter detection and prediction method and device, and the method comprises the following steps: carrying out the power distribution of a light beam of a broadband light source through employing a light splitting element based on the emission of the broadband light source, and forming a detection light beam and a reference light beam, and guiding the detection light beam to pass through a preset open atmosphere optical path, and guiding the reference light beam to pass through a known refractive index stabilizing medium or a vacuum pipeline. The detection light beam and the reference light beam are formed through light splitting of the broadband light source, the detection light beam penetrates through the open atmosphere path, the reference light beam passes through the stable medium, Fourier transform is carried out on interference signals of the two light beams to extract wavelength phase difference mapping data, and tiny optical path change caused by atmospheric refractive index disturbance can be captured. Compared with the traditional single-point or single-path measurement, the sensing sensitivity and the measurement dimension of the atmospheric refractive index spatial nonuniformity are improved by using the broadband spectral information.

The invention provides a container multi-angle imaging quality detection method and system, and the method comprises the steps: carrying out the illumination and imaging of a target container from a plurality of preset visual angles through employing light sources with different wavelengths, and obtaining a refraction displacement fingerprint data set; carrying out regional division on the surface of the container according to the data set, calculating the refraction influence degree of each region under different visual angles, and generating a regional visual angle weight distribution diagram; performing optical path reverse tracking processing on the images acquired at each view angle by using the distribution map, constructing a light propagation path model, and performing position mapping and distortion compensation to obtain a corrected image; and finally, according to the corrected image and the regional view angle weight distribution diagram, defect detection is carried out by adopting a regional adaptive fusion algorithm. According to the method, through technical means such as region adaptive division, optical path reverse tracking and region adaptive fusion, multi-view images can be accurately aligned and fused, meanwhile, observation characteristics of different regions are considered, and the reliability of a defect detection result is ensured.

The invention relates to an error compensation method of a birefringence self-calibration laser level meter, in particular to the field of laser level meters, and aims to improve the precision of the laser level meter by combining a birefringence effect, physical modeling and neural network optimization. Firstly, temperature data are collected in real time, Kalman filtering is used for noise reduction, and accurate data are provided for physical modeling; then, through physical constraints such as a heat conduction equation and a Jones matrix, a coupling relation between the temperature gradient and optical parameter changes is established; then, dynamically optimizing the refractive index correction by using a physical information neural network to avoid an overfitting problem; and finally, calculating optical path difference compensation by using a hardware accelerator, correcting a system error in real time, and feeding back and adjusting a network weight. According to the method, the precision and the stability of the laser level meter in an environment with relatively large temperature change are effectively improved.

The invention discloses an optical time stretching sweep frequency interference measurement Doppler effect compensation method and device, and relates to the technical field of non-cooperative target absolute distance measurement. In order to solve the defect that the absolute distance measurement precision is reduced due to the fact that the Doppler effect cannot be efficiently suppressed in a complex environment in the prior art, the technical scheme provided by the invention comprises the following steps: generating a sweep frequency laser signal and splitting the sweep frequency laser signal to form measurement light, reference light and resampling light; performing time stretching processing on the reference light to obtain a chirp signal; performing interference on measurement light and the chirp signal to obtain a measurement interference signal; performing interference on the reference light and the resampling light to obtain a reference interference signal; performing cross-correlation processing on the measurement interference signal and the reference interference signal, and extracting an optical path difference; and carrying out distance calculation by combining the resampling data, and outputting a target distance after the Doppler effect is compensated. The method is suitable for optical measurement work for performing high-precision absolute distance measurement on a non-cooperative target in a tiny vibration or disturbance environment.

The invention discloses an all-optical ultrasonic imaging system based on phase modulation, and belongs to the technical field of imaging. The system comprises a laser assembly, an ultrasonic detector, an interference device and an imaging assembly, the laser assembly is used for providing continuous laser for the interference device; the interference device comprises a reference optical fiber arm, a sample optical fiber arm and an optical path adjusting device and is located between the ultrasonic detector and the imaging assembly. Wherein the interference device is used for dividing laser into reference light and detection light, and transmitting the detection light to the ultrasonic detector for phase modulation; the optical path adjusting device is used for adjusting the optical path difference of the two arms, forming interference light of the reference light and the phase-modulated detection light and inputting the interference light into the imaging assembly; the ultrasonic detector is used for generating ultrasonic waves, projecting the ultrasonic waves to a to-be-detected area, and performing phase modulation on the detection light in response to ultrasonic echoes of the to-be-detected area; and the imaging assembly is used for generating a corresponding image according to the interference light.

The invention provides an optical measurement method and device, and belongs to the technical field of optical measurement, and the method comprises the steps: starting a light source with the wavelength changing dynamically to generate a sweep frequency optical signal; dividing the light into a measuring beam and a reference beam by using a light splitting component, guiding the measuring beam to irradiate a target to be measured and then return along the same path, and guiding the reference beam to enter an optical component of which the optical path changes along with the wavelength and then return; based on the low-coherence characteristic of the light source, when the optical paths of the two light beams meet the interference condition, detecting an interference signal by using a sensing component; the optical path difference is determined according to time information in the interference signal, and the thickness of each reflection interface is calculated by combining refractive index data of a target to be measured. Different from the traditional low-coherence interference measurement which depends on a motor and the like to control the movement of a reflector, the method avoids the limitation of mechanical driving on the measurement frequency, and achieves the high-speed optical thickness measurement.

The invention relates to the technical field of total phosphorus detection, in particular to a method for determining total phosphorus in water, which comprises the following steps: 1) digestion treatment: adding an oxidant into a water sample to be detected, and then performing microwave digestion treatment to obtain digested water; a molybdate reagent is added into the digested water, then an improved ascorbic acid solution is added, a chromogenic reaction is completed at the set temperature, and the improved ascorbic acid solution is obtained by mixing an ascorbic acid solution and sodium ethylene diamine tetracetate; measuring the concentration: measuring the absorbance value of the obtained color development product by using a spectrophotometer and a long-optical-path cuvette; and drawing a standard curve: using a phosphorus standard solution as a quality control sample, adding a plurality of calibration points in a low-concentration interval of 0.0-0.1 mg / L, carrying out colorimetric determination, and establishing quadratic equation fitting according to absorbance and concentration so as to determine the total phosphorus content of the water sample to be detected, and the method has the advantages of high sensitivity and good accuracy in total phosphorus testing.

The invention relates to the technical field of large-aperture telescope construction, in particular to a large-aperture spliced telescope progressive generation method, which comprises the following steps of S1, constructing a local co-phase region at the edge of a large-aperture telescope by using spliced sub-mirrors through assistance of a small-aperture secondary mirror, and forming local co-phase imaging capability; s2, the step S1 is repeated, and equal-area local co-phase regions are constructed at the symmetrical positions of the edge of the large-aperture telescope; s3, constructing an interference imaging system through optical path difference adjustment, zero interference elimination and two symmetrical local co-phase regions; s4, repeating the steps S1 to S3, constructing more symmetrical and equal-area local co-phase regions at the edge of the large-aperture telescope, and constructing interference imaging in which the plurality of symmetrical local co-phase regions participate; and S5, constructing local co-phase regions in sequence from the edge to the center until the construction of the whole large-aperture telescope is completed.

The invention relates to the technical field of length measurement, and particularly discloses a length measurement device based on laser interference, which comprises a laser measurement module, an air curtain channel module, an air curtain construction module and a channel adjustment module, the laser measuring module is used for transmitting and receiving laser, the optical path difference change is measured according to the interference principle, and the micro length change of the workpiece can be continuously and accurately measured in real time while the machining module carries out machining operation on the workpiece; a linear channel is formed between the laser head and the measuring reflector through the air curtain channel module, inert gas is continuously introduced into the channel through the air curtain construction module, and an air curtain atmosphere with stable laminar flow is formed, so that pollutants and interference factors such as oil mist, dust, cutting fluid splashing and hot air turbulence generated in a machining area are effectively blocked, and the machining precision is improved. Therefore, the measurement light beam is prevented from being interfered by environmental factors in the propagation process.

The embodiment of the invention discloses a laser and related equipment and method. The laser comprises a laser generation module, a first coupler and a reflective space structure composed of at least one reflective element, multiple paths of laser generated by the laser generation module form optical pulses in the first coupler through interference, the optical pulses are divided into two paths, one path of first optical pulse is transmitted to the reflective element, and the other path of first optical pulse is transmitted to the second coupler. And the other path of second optical pulse is output. The first light pulse is reflected back to the laser generating module by the reflecting element. The optical path of the optical pulse transmitted in the space can be changed by controlling the reflection element to move, so that the repetition frequency of the optical pulse generated by the laser generation module can be adjusted. It is understood that the back-and-forth optical path of the optical pulse in the space can be adjusted by controlling the reflection element to move, equivalently, the optical path of the optical pulse in the space is changed exponentially, and the repetition frequency of the optical pulse can be adjusted in a larger range, for example, large-range frequency modulation over 2 MHz can be achieved.

A push-pull type optical fiber MEMS accelerometer based on a Michelson interferometer comprises a mechanical assembly and two sensing optical fibers, the mechanical assembly is composed of a fixed base and an acceleration sensing chip, the acceleration sensing chip comprises an external frame, a mass block and two sets of spring cantilever beams, the external frame is provided with a thin optical fiber groove, and the thin optical fiber groove is provided with an optical fiber. The mass block is provided with two convex structures serving as reflecting surfaces, and two air cavities are formed between the end face of the sensing optical fiber and the top faces of the convex structures of the mass block and serve as sensing arms of the Michelson interferometer. When the accelerometer is subjected to the action of external acceleration, the mass block moves relative to the external frame to drive the cavity lengths of the two air cavities to change in a push-pull manner, so that the optical path is changed and an interference signal is generated. Interference signals are acquired and demodulated through a photoelectric detector, a data acquisition circuit and a computer, and vibration acceleration signals can be obtained. The invention has the advantages of high sensitivity, strong common-mode noise suppression capability and the like, and is suitable for various dynamic vibration response measurement occasions.

The invention discloses a high-precision spectral interference signal demodulation method for micro distance measurement. The method comprises the steps of S1, interference spectrum shaping; measuring an interference spectrum and a reference spectrum; selecting a six-item combined cosine window as a primary function of an interference signal to obtain a shaped interference spectrum; s2, performing non-uniform Fourier transform to obtain a frequency spectrum of the target signal; s3, on the basis of a multi-spectral-line interpolation algorithm, interpolation is carried out on the window function to solve a fitting function, and a center frequency k is obtained; and S4, outputting a result. And solving and outputting an optical path difference d. According to the method, a six-item cosine combination window is selected as a primary function of an interference signal, and the problem that the accuracy of signal extraction is influenced by mutual superposition of side lobes and even main lobes of a direct current item and a solved frequency item is solved; an interference spectrum is processed by using a fast non-uniform Fourier transform algorithm, accuracy can still be kept under the conditions that the distance to be measured is increased and sampling is gradually sparse, and the problem of resampling deviation caused by a traditional interpolation method can be solved.

The invention discloses a method and a device for correcting laser focusing aberration in a transparent material, and belongs to the technical field of laser processing. The method comprises the steps that a machining light path containing an object plane, an aspheric reflector and a 4F device is built in Zemax, the surface type of the aspheric reflector is optimized with the minimum focus aberration as the target, and a rise table is derived; an optical path difference and a laser phase are calculated through Matlab, and a phase diagram is generated; and an actual machining light path is built, and a phase diagram is loaded to achieve low-aberration machining. Simulation optimization and phase modulation are combined, aberration caused by refractive index difference is effectively counteracted, wavefront errors are reduced by 58%, the thickness of a machining damage layer is reduced by 70%, the method is suitable for various transparent materials, the machining precision and the material utilization rate are improved, and the method is suitable for high-precision laser machining scenes.

The invention relates to the technical field of real-time rendering, in particular to a real-time light and shadow tracking and rendering system for a virtual reality environment, and the system comprises a light source reachability pre-calculation module which projects a connecting line to a light source to each unit in a three-dimensional grid covering a volume medium based on the scene geometry of the virtual reality environment and the position of the light source. According to the method, the connection line shielding proportion judgment is executed based on the scene geometry and the light source position, the optical path density field data reflecting shielding space distribution is established, and the density representation of illumination reachability is constructed on the voxel level, so that the subsequent light path propulsion has the density sensing capability, and the recognition precision of the complex shielding structure is enhanced. And extracting a normal gradient in the G-Buffer and a brightness variance of a previous frame, fusing an inter-frame geometric boundary change and a brightness fluctuation behavior, constructing a pixel-level feature intensity value set, and writing the pixel-level feature intensity value set into a two-dimensional map for guiding subsequent sampling density regulation and control and realizing local response of cross-frame dynamic information.

The invention provides a rapid evaluation method and system for the soil fertility level, and relates to the technical field of soil fertility detection.The rapid evaluation method comprises the steps that an original absorbance spectral data curve is obtained by scanning a soil sample, the moisture peak absorbance, the actual peak position wavelength and the moisture synthetic frequency characteristic peak width are extracted, and a spectral data basis is provided; a water-salt optical path coupling factor is calculated, water-salt correction operation is carried out in combination with a volume correction coefficient, a virtual dry soil spectrum data curve is obtained, interference of salt on a water optical path is quantified, and a water background and salt masking are eliminated; constructing a characteristic virtual baseline of the organic matter and the total nitrogen, calculating an integral area to obtain characteristic intensity of the organic matter and the total nitrogen, and providing a physical input variable for quantitative inversion; introducing a water-salt optical path coupling factor to invert the organic matter content and the total nitrogen content, and correcting signal depression caused by salt stress; the effective fertility index is calculated and graded by combining the organic matter content and the total nitrogen content of the soil, and the actual fertilizer supply capacity of the soil is comprehensively evaluated.

The present invention discloses a device and method for semiconductor grain double-sided simultaneous fully equal optical path confocal imaging detection based on polarization separation imaging method. The device includes a CMOS or CCD polarization camera, a telecentric imaging lens, a polarization cube beam splitter, a right-angle image rotation prism, a semiconductor grain, and a transparent glass stage for placing the semiconductor grain, which are sequentially arranged in the optical path direction. The advantages of the device and method of the present invention are as follows: It can achieve double-sided simultaneous fully equal optical path confocal polarization imaging detection of the object to be measured, that is, △ = 0, without the need to use a large-depth-of-field telecentric lens to compensate for the optical path difference of double-sided imaging; the double-sided simultaneous polarization imaging detection device has a simple and compact structure and is easy to assemble and debug.

The invention relates to the technical field of image processing, in particular to an optical thin film quality detection method based on image processing, which comprises the following steps: S101, acquiring a transient light field image sequence of an optical thin film in a dynamic stress field; s102, performing spectral analysis on the brightness time sequence of each pixel point, extracting a dominant frequency component as a brightness oscillation period, processing time domain fluctuation data by adopting a Fourier transform algorithm, and calculating a local optical path difference variation based on the brightness oscillation period of each pixel point in the image sequence; and S103, projecting the phase distortion field to a preset film elastic modulus distribution model, establishing a phase distortion-stress distribution-defect mapping relation, and identifying a modulus mutation region. A dynamic stress field is generated through the synergistic effect of mechanical vibration and thermal radiation, remarkable stress concentration can be generated at the micro-defect position, the deformation difference of the micro-defect is amplified, and therefore the sensitivity of defect detection is improved.

The invention belongs to the field of optical coherence layer imaging, and particularly discloses a spectrum calibration method for a linear field spectral domain OCT (optical coherence tomography) system, which comprises the following steps: acquiring interference signal instantaneous phases corresponding to two optical path differences by adjusting a lifting platform at a sample mirror in the linear field spectral domain OCT system, and subtracting the interference signal instantaneous phases to obtain an instantaneous phase difference; based on the calibration light source, discrete spectral lines are generated on a detector through a sample arm in the shielding line view field spectral domain OCT system, and spectral intensity distribution corresponding to the calibration light source is obtained; calculating the sub-pixel position of the peak value of each spectral line and the instantaneous phase difference corresponding to the sub-pixel position based on the instantaneous phase difference and the spectral intensity distribution corresponding to the calibration light source; and based on the wave number and the instantaneous phase difference corresponding to each spectral line, determining a linear relationship between the instantaneous phase difference and the wave number through linear fitting, and calibrating the corresponding wave number based on the linear relationship. According to the method and the device, the linear field OCT spectrum calibration result with higher precision can be realized.

The invention discloses a phytoplankton primary productivity in-situ fluorescence detection device and method, and belongs to the technical field of aquatic ecology monitoring. The device adopts a modular integrated design and comprises a multi-band LED excitation light source, a laser induction module, a photomultiplier receiving system and an anti-vibration circuit structure, and synchronous detection of chlorophyll concentration and photosynthetic activity is realized through a short-optical-path optical design. The method is based on spectrum inversion and fluorescence kinetic analysis, a standard spectrum library is constructed, chlorophyll concentration distribution and photosynthetic parameters are calculated through least square fitting, and primary productivity data are output in combination with a photoresponse model. The device has the diameter of 67 mm, supports deployment of Argo and other mobile platforms, solves the problems that a traditional method is poor in timeliness and equipment is discrete, and has the advantages of being high in detection efficiency, high in anti-interference performance and wide in applicable water depth range.

The invention is suitable for the technical field of optical measurement, and provides a back drill stub length detection method, a signal processing assembly and a system. The method for detecting the length of the back drill stump comprises the steps that the optical path difference between first reflected light and second reflected light is obtained, the first reflected light is reflected light generated by reflecting an incident light beam of a back drill hole to be detected on the surface of a dielectric layer of the back drill hole to be detected, and the second reflected light is reflected light generated by reflecting the incident light beam of the back drill hole to be detected; the second reflected light is reflected light obtained by reflecting a light beam, passing through the dielectric layer, of the incident light beam by the signal layer of the back drilling hole to be detected; and according to the optical path difference and the refractive index of the dielectric layer, determining the stub length of the back drilling hole to be measured. According to the embodiment of the invention, the same incident light beam can be reflected by different layers of the back drilling hole to be detected, the stub length is determined based on the optical path difference between the two reflected light beams, and the detection efficiency is improved.

A laser processing apparatus includes a laser oscillator that oscillates processing laser light to be incident on a processing point on a processing surface of a workpiece, a coupling mirror that deflects or transmits the processing laser light and measurement light to be incident on the processing point toward the processing point, a measurement light deflection unit that changes an incident angle of the measurement light on the coupling mirror, a lens that concentrates the processing laser light and the measurement light on the processing point, a controller that controls the laser oscillator and the measurement light deflection unit, a measurement processor that measures a depth of a keyhole generated at the processing point by the processing laser light by using an optical interference signal based on an interference generated by an optical path difference between the measurement light reflected at the processing point and reference light, and a beam position measurement unit that measures positions of the processing laser light and the measurement light.

The invention discloses a device and a method for manufacturing a laser three-dimensional body with a complex structure, and solves the problems of low processing precision and low processing efficiency of the existing femtosecond laser processing technology. The light beam position presetting unit, the dispersion compensation unit, the acousto-optic modulation unit, the optical relay compensation unit and the microscopic focusing unit are sequentially arranged on a light path where the processing laser is located in the emitting direction of the processing laser. The light beam position presetting unit is used for adjusting the optical axis space position of the processing laser; the dispersion compensation unit is used for performing dispersion compensation on the processing laser after the optical axis spatial position adjustment; the acousto-optic modulation unit is used for dividing the processing laser subjected to dispersion compensation into a plurality of sub-beams through amplitude modulation of electric signals with different and / or the same frequency, and adjusting the spatial position of each sub-beam; the optical relay compensation unit is used for adjusting the optical path of each sub-beam; and the microscopic focusing unit is used for focusing the sub-beams after the optical path adjustment.

The invention discloses a dynamic leaching-spectrophotometric detection method for the release rate of nutrients in a slow-release fertilizer, and relates to the field of agrochemical analys.The detection method comprises the following steps that S1, a slow-release fertilizer sample is placed in a leaching column to be leached, and leachate is collected; s2, sequentially adding a masking agent solution and a chromogenic reagent into the leachate, and carrying out chromogenic reaction; s3, pumping the solution into a double-optical-path flow cell, and measuring absorbance values under a target nutrient characteristic absorption wavelength and a background interference characteristic wavelength; s4, calculating the corrected net absorbance; and S5, calculating the nutrient concentration, and drawing a nutrient release kinetic curve. By adopting a dual-wavelength synchronous detection and real-time dynamic subtraction correction algorithm, the method can eliminate system errors of time-varying background chromaticity, so that accurate and reliable absorbance readings can be obtained at the initial stage of nutrient release even if the nutrient concentration in the leachate is very low, thereby ensuring the authenticity of the initial stage of a release curve and improving the accuracy of nutrient release. And initial release kinetic parameters are accurately captured.

A self-calibrating hybrid spectrophotometer comprises a receptacle for receiving the cuvette, first and second optodes that are configured to permit light to enter the cuvette, third and fourth optodes that are configured to permit light to leave the cuvette, and a controller that is configured to control delivery of light to one of the first and second optodes. Light entering one of the first and second optodes is received at the third and fourth optodes after having interacted with the turbid sample along different paths having different lengths. Measurements made at the third and fourth optodes in response to having illuminated both the first and second source optodes provide two slopes of optical transmittance as a function of path length. The spectrophotometer uses these slopes to identify a slope that is indicative of the absorption coefficient and the reduced scattering coefficient of the sample.

The invention relates to the technical field of medical image information processing, discloses an ICG fluorescence image and MRCP three-dimensional model registration fusion display method and system, effectively solves the problems of deep biliary tract structure blurring and form distortion caused by liver tissue scattering effect in intraoperative fluorescence imaging, uses a preoperative model as anatomical prior, and improves the accuracy of the intraoperative fluorescence imaging. A viewpoint correlation optical path depth field is constructed through reverse ray tracing, a spatial variation point spread function is generated accordingly, physical reverse recovery of scattering halo in a fluorescence image is achieved, non-specific background noise such as vascular leakage is effectively inhibited in combination with topological gravitational constraint of a central skeleton, and the detection accuracy is improved. The real pipe diameter and the center line position of the deep bile duct are accurately recovered, non-rigid registration correction is performed on the three-dimensional model based on the recovered high-fidelity image, and projection errors caused by respiratory movement and soft tissue deformation are eliminated.

The invention provides a Mach-Zehnder interferometer optical fiber sensor based on an arc-shaped concave cavity single-mode optical fiber. The device is characterized by comprising an incident optical fiber 1, a beam splitter 2, an interference arm 3, a beam combiner 4 and an emergent optical fiber 5 which are connected in sequence. The incident optical fiber 1 is used for transmitting an input optical signal, the beam splitter 2 couples the optical signal in the incident optical fiber 1 into the interference arm 3, the interference arm 3 is used as a transmission waveguide, three arc-shaped concave cavities with different depths and curvature radiuses are arranged in the interference arm 3, and when a solution to be detected is immersed in the concave cavities, the refractive index change modulates an interference spectrum through an optical path difference and a phase difference; according to the design of the three concave cavities, refractive index distribution of three independent positions in the reaction process can be measured at the same time, the beam combiner 4 recombines optical signals in the interference arm 3 and couples the optical signals into the emergent optical fiber 5, and the emergent optical fiber 5 is responsible for outputting the optical signals and transmitting the optical signals to detection equipment for analysis. According to the invention, multi-position synchronous detection is realized through the multi-cavity gradient sensitive characteristic and in combination with the femtosecond laser micromachining technology, the problem of accidental errors of a traditional single-position sensor is solved, and the sensor is suitable for scenes such as microfluidic reaction requiring dynamic monitoring of refractive index change.