The zoom optical system is not only suitable for daily life such as photography, surveillance and microscopy, but also widely used in aerospace and national defense construction. With the expansion of the application range, there are more and more requirements for its performance indicators. This design realizes a 15 mm~300 mm wide spectrum four component continuous zoom optical system. The system uses a positive group compensation structure to achieve 20 times optical zoom, it can work in the spectrum range of 450nm~900nm, and the working temperature range is − 40 ℃~ 60 ℃. It uses 18 spherical glass lenses with a total length of 160mm, a maximum aperture of 66 mm, a long focal F number of better than 5, the system has compact structure and miniaturization requirements. In the visible light band, realize the modulation transfer function (MTF) of the central field of view >0.4@145 lp/mm, MTF of full field of view >0.2@145 lp/mm. In the near infrared band, MTF of the central field of view >0.4@60 lp/mm and MTF of full field of view >0.2@60 lp/mm. From the design results, the design meets the requirements of high performance index, and has certain reference significance for the design of zoom optical system with wide spectrum, large zoom ratio and miniaturization.

As an important accessory of the high and low temperature test device of the photoelectric imaging system, the optical window assembly is assembled on the side of the high and low temperature test box. Combined with the comprehensive detector of the photoelectric system outside the box, it is used to detect the performance index of the photoelectric imaging system under high and low temperature conditions. It is an important part of the high and low temperature performance detection device of the photoelectric imaging system. According to the application requirements and material analysis, multispectral ZnS is selected as the optical window material to meet the performance index detection requirements of multispectral photoelectric system; Through the heat conduction theory, the low-temperature service state of the optical window module is analyzed, focusing on the influence of the heating of the window module under the low-temperature condition on the surface shape of the window module, and the structural form to realize the micro stress assembly and the design scheme to solve the frost and fog of the window module under the low-temperature condition are put forward; The finite element calculation results are extracted, processed and combined by sigfit, and the caliber is analyzed by code v φ The wave aberration RMS of 310mm window module in the temperature range is better than that of λ/ 15. They all meet the optical performance requirements of window components and have been verified by the physical prototype. Therefore, the structural design scheme of the multispectral optical window assembly not only meets the requirements of multi band use, but also meets the requirements of low-temperature defrosting and defogging, and ensures the optical performance requirements under high and low temperature conditions.

Ultraviolet (UV) image intensifiers are widely used in corona detection, strategic national defense, scientific research and other fields. However, due to the lack of available materials for the UV optical lens and the difficulty of chromatic aberration correction, it is difficult to meet the needs of wide spectrum. The applicability of single-layer diffractive optical element (SLDOE) and double-layer diffractive optical element in broadband UV optical system is analyzed. A set of UV optical systems with wide spectrum and high resolution are designed respectively. The working wavelength range of the single-layer diffractive UV optical system is 230 nm~280 nm, and the modulation transfer function (MTF) value at the cut-off frequency of 60 lp·mm⁻¹ is better than 0.47; the working wavelength range of the double-layer diffractive UV optical system is 200 nm~ 400 nm, MTF value at the cut-off frequency of 60 lp·mm⁻¹ is better than 0.49. The design results show that DOE can effectively correct the chromatic aberration of the UV spectrum. Compared with the existing wide spectrum UV system, the optical systems are relay imaging systems with wider UV spectral range and higher imaging resolution in this paper.

Low illumination night vision equipment based on CMOS devices has good concealment and lower cost than infrared thermal imaging equipment. It is an important means to expand human visual perception under low illumination conditions and widely used in military and civil fields. In order to meet the requirements of equipment maintenance and support under the condition of low illumination at night, a large field of view low illumination night vision goggle optical system is designed. By selecting the appropriate optical glass material, it has a good spectral response in the visible/near infrared band. The designed large relative aperture eyepiece has a field of view angle of 74.46°, focal length of 46mm, F# 1.2, distortion less than −7.14%, total length of the system less than 80mm and lens weight less than 100g. Under the spectral range of 486 ~ 950nm, the eyepiece can meet the maintenance, training and scene observation under the condition of no lighting at night, which provides a new technical means for the development of optical module of low illumination night vision headwear system.

This paper designs an optical system for panoramic surveillance cameras that can achieve clear all-weather imaging. Using a panoramic annular structure, the structure is divided into two parts: camera head unit and relay lens unit. The camera head unit completes the full field of view target search, The relay lens unit performs secondary imaging of the intermediate virtual image formed by the head unit and converges it on the detector. The design adopts multiple structural optimization methods to achieve visible light and near-infrared dual band imaging. The field of view of the optical system is 360°×（40°~100°）, the focal length is −2.75 mm, and the number of F is 3.28. The modulation transfer function (MTF) value of design results is close to the diffraction limit at the full field of view, The diffuse spot radius of each field of view is less than the selected CCD pixel size, The distortion is less than ±2%, and the day and night defocus is less than 0.002 mm, The design results well meet the requirements of all-weather panoramic monitoring.

A scheme for coherent noise suppression by an off-axis illumination system is proposed. An illumination system with the ability to suppress coherent noise is designed, and the illumination system is simulated by the non-sequential mode of Zemax to obtain an off-axis annular light spot with a thickness of 90 μm. To verify the ability of this illumination system to suppress coherent noise, it is used as the light source of a 3/4-inch Fizeau interferometer, and a comparison experiment is set up with a light source wavelength of 632 nm, and circular noise spots of size 120~500 μm and scratches of 100×350 μm are set. Error analysis of this illumination system was performed to optimize the imaging quality of the illumination system and adjust the parameters of the interferometric system, and finally, the contrast of the interference fringe was improved to 97.60% with illumination light of 42 μm ring thickness and an interference cavity length of 15 mm.

DETR is a target detection algorithm based on transformer, which has the advantages of fast detection speed and good detection effect. A measurement system based on DETR and binocular vision principle for people, cars, bicycles, signal lights and other targets in road environment is introduced. The principles of binocular ranging, camera calibration, target detection and target matching are analyzed, and the measurement system is constructed on this basis. The target detection algorithm is used to detect the target in the field of vision, and the principle of binocular vision is used to measure the distance of the detected target. The source of measurement error in the measurement system is analyzed and the influence on the results is calculated. The algorithm is tested in Kitti data set and real environment. The system baseline is 45 cm, the detection rate of 15-80 m specified target is higher than 90.6%, and the ranging error is less than 5.8%. The algorithm in this paper runs on RTX 2080ti platform and can run in real time.

In order to meet the high-precision measurement requirement of spectral emissivity of high temperature material coating, including the stealthy materials, thermal protection materials, heat insulating coat and so on, the measuring methods for normal spectral emissivity of materials at 1 273 K～3 100 K was explored. A measurement model of normal spectral emissivity of materials was established firstly based on the emissivity definition. On this basis, the measurement facility of normal spectral emissivity of materials was built, the wavelength range is 0.7 μm to 14 μm. In order to overcome the technical difficulties of the cavity effect caused by heating the sample in the measuring device, a temperature sample furnace with a movable graphite crucible was developed, and good experimental results were obtained. The normal spectral emissivity of two samples (SiC and low emissivity coating) were measured by this facility. The results show that normal spectral emissivity of two samples decrease with wavelengths and increased with temperature. Finally, the measurement uncertainty of normal spectral emissivity of materials at high temperature was analyzed, the relative expanded uncertainty is 3.6%.

Research of theoretical modeling and simulation analysis for Fast Steering Mirror (FSM) is carried out to guide the design of FSM effectively. Compared with the single degree of freedom motion model, the multiple degrees of freedom motion differential equation of a two-axis FSM is derived based on the dynamics analysis. The transfer function of the controlled object and rejection of the base disturbance is developed. The influence of the flexible hinge's resonant frequency on the characteristic of the controlled object has been simulated. When the rotation natural frequency is high, the controlled object is an under damped system which has resonance peaks. The simulation model is built for the FSM control system with the structural characteristic. The influence of the bias between the center of mass of the load and the support center of the flexible hinge and the structural resonant frequency on the disturbance rejection characteristic is researched. The disturbance rejection will be better when the non-working axis resonant frequency is higher. The non-working axis resonant frequency should be more than two times of the gain crossover frequency. The working axis resonant frequency should be selected in consideration of the requirement of the disturbance rejection performance and the limitation of the motor torque. Finally, the simulation model is validated via the vibration experiment.

In near-shore scenes, under the influence of background, the probability of false detection and low detection accuracy of ship critical parts are high. To address the above problems, this paper proposes a detection network for ship critical parts based on semantic features, which named CPDNet (critical part detection network). Firstly, by optimizing the network structure and adopting attention mechanism, the feature expression ability and the perception ability of the ship's critical parts are improved. Secondly, based on semantic information, a semantic mask module is designed to reduce the impact of background on detection accuracy. In addition, the angle parameter is added to make the network applicable to targets with orientation. Finally, a ship's critical parts dataset, named CP-Ship, is constructed to verify the effectiveness of the proposed network. The experimental results on the CP-Ship dataset show that the average accuracy of the proposed network is 11.35% higher than RetinaNet. Compared with other network models, the proposed network performs well in both detection accuracy and speed.

Camouflage effect evaluation is an important content in the development of camouflage technology. In order to make full use of spectral details to evaluate the hyperspectral camouflage effect of targets, a camouflage effect evaluation method based on spectral index is proposed, which has the advantages of visualization and quantitative analysis. In terms of visualization, the hyperspectral image is segmented by spectral index to realize the camouflage effect evaluation of visual interpretation; In terms of quantitative analysis, based on the existing remote sensing spectral indexes, new camouflage spectral indexes are constructed to quantify the spectral characteristics of the target and background, and the spectral consistency coefficient index is proposed to weight and synthesize the spectral indexes, so as to quantitatively evaluate the camouflage effect of the target. The experimental results show that our method can effectively identify the hyperspectral camouflage effect before and after target camouflage, and when the similarity of traditional indicators reaches more than 99%, this method can still effectively identify the target and give an objective evaluation. Its evaluation results are more accurate, comprehensive, scientific and reasonable in terms of the consistency of single spectral segment and the overall matching of wide spectral segment.

Optical fiber refractive index sensor is widely used for monitoring in various complex environments. A high-sensitivity refractive index sensor based on the structure of few-mode fiber (FMF)-coreless fiber (CLF)-FMF was designed, and the experimental verification was carried out. The sensor consisted of a thinned section of CLF fused between two small sections of FMF to form a Mach-Zehnder interferometer (MZI) for measuring external refractive index, and the fiber Bragg grating (FBG) was used for temperature compensation. The resonance trough of interference spectrum generated by MZI structure was affected by both refractive index and temperature, while FBG was only affected by temperature. The sensitivity matrix was constructed by using the refractive index and temperature sensitivity coefficients of MZI and FBG to realize the simultaneous measurement of refractive index and temperature. Experimental results show that the refractive index sensitivity of MZI is 345.66 nm/RIU, and the temperature sensitivity is 0.0134 nm/℃. Meanwhile, the temperature sensitivity of FBG is 0.0104 nm/℃.

The evolution between different types of pulses is the embodiment of the passive mode-locking fiber laser rich dynamics. A hybrid mode-locking fiber laser with multiple pulse switching was reported. When the pump power was 400 mW, the mutual switch of pulses between soliton molecules, harmonic mode-locking and soliton clusters were realized. Then, when the pump power was increased to 600 mW, the noise-like pulse output was realized, and the corresponding output power and single pulse energy were 15.2 mW and 0.86 nJ, respectively. By adjusting the polarization controller, the central wavelength of noise-like pulse could be tuned from 1 895 nm to 1 930 nm. The designed laser has the advantages of mode-locking switching, wavelength tuning and automatic start.

In the evaluation and analysis of high-power laser system, the beam quality of laser is the decisive factor of the system beam quality and also an important index of acceptance and appraisal of laser, among which the beam divergence angle is an important parameter to identify the laser beam quality. The range of laser wavelength tested in this system is relatively wide, generally between 0.532 μm~10.6 μm, and no suitable detector can cover the whole band. Therefore, a new method was adopted to solve the measurement problem of wide-band beam divergence angle. The method of combining charge coupled device (CCD) imaging and scanning slit was used to measure the wide-band beam divergence angle. The CCD method was used to measure the laser beam divergence angle in visible and near-infrared band (0.532 μm~1.2 μm), and the scanning slit method was used to measure the laser beam divergence angle in mid-infrared band (1.2 μm~10.6 μm). The combination of the two methods can accurately measure the laser beam divergence angle in different wavebands.

In view of the phenomenon that the scale factors of the laser gyro with total reflection prism changes periodically with temperature, the influence of temperature changes on the ring laser area under the condition of frequency stabilization was studied by matrix optical method. The relationship between the scale factors of the laser gyro with total reflection prism and the frequency stabilization voltage was obtained, and it was pointed out that the beam offset was the cause of the periodic change of scale factors with temperature. According to the relationship between the scale factors and the frequency stabilization voltage, the scale factor compensation model of the laser gyro with total reflection prism was established, and the nonlinearity of the scale factors before and after compensation was compared through experiments. The results show that the nonlinearity of the scale factors is increased by more than one order of magnitude by using the proposed model to compensate the scale factors of the laser gyro with total reflection prism. The research has certain reference value for improving the performance of laser gyro with total reflection prism.

Microchip solid-state laser is an important light source for precision measuring instruments because of its small size and long life. The plano-plano and half-external cavity Nd:YAG and Nd:YVO₄ microchip lasers were constructed. The length of the laser resonator was changed by controlling the expansion and contraction of the piezoelectric ceramics. At the same time, the longitudinal mode and wavelength were observed by using F-P scanning interferometer and wavemeter. The cavity tuning characteristics of the two microchip solid-state lasers were studied, including the relationship between the cavity length and the optical power, the optical power and the variation rules of single and double longitudinal modes in the process of laser longitudinal mode sweeping through the laser output bandwidth. The experimental results show that the single and double longitudinal modes appear alternately during the process of cavity tuning, and the cavity length and pump current jointly affect the output mode and optical power of the laser.

In order to break through the restriction of application scene caused by the limitation of single wavelength of conventional laser projector and realize the layer projection of different parts, different materials and different assembly processes, a multi-color layer laser scanning and auto-focus projection system was designed and established. Two wavelengths of laser were adopted as the light source, and according to the different positions of dichromatic mirror, the two laser scanning and auto-focus projection schemes of multi-color co-optical axis and separate optical paths were proposed, and the corresponding mathematical models of optical system were deduced. By adjusting the distance between mirror groups through the auto-focus function of the system, the minimum light spots of different colors could be focused on the projectors at different distances. Two kinds of projection optical systems were simulated by ZEMAX optical design software, and the reliability and projection effect of the two systems were compared and analyzed. The experimental results show that on the projection plane at 3 m, the spot diameter of various wavelengths of the co-optical axis system is within 0.8 mm and the spot size is uniform, which can achieve the scanning and auto-focus projection function of multi-color layers.

The natural forest areas in China are widely distributed and the terrain is complex. Relying on the traditional patrol detection method of forest rangers to prevent and control forest diseases and insect pests is inefficient, so it is difficult to find early forest diseases and insect pests in time, which may miss the best time for prevention and control. In view of this problem, a deep learning network based on multispectral image detection of forest diseases and insect pests was designed, and a set of detection software was developed. Through the UAV hanging flight experiment, the built deep learning network was used to complete the detection of infected areas in forest areas, and the detection results were analyzed.

In the existing methods, images of markers are often taken from bottom to top. When the blade is twisted greatly, there is an obvious angle between the principal optic axis of the camera and the normal vector of a marker plane, resulting in perspective distortion of the captured images, which leads to relatively large measurement errors. In order to solve the problem raised above, a method of measuring the torsion angle of helicopter blade root based on the perspective transformation was proposed. Firstly, the target was vertically fixed under the blades, so that the camera was directly facing the propeller hub to capture images. Secondly, the four vertex coordinates of the blades in the target images of azimuth to be measured and positive azimuth were calculated when operating at the low-speed leveling state, and the perspective transformation matrix of the azimuth to be measured was solved. Moreover, the perspective transformation matrix was used to correct the distorted image of the azimuth to be measured under the high-speed motion state of the blades. Finally, the coordinates of the circle center in the reference image and the corrected image were obtained, and then the torsion angle of azimuth to be measured was calculated. The experimental results show that the measurement error of each azimuth is less than 0.2°. This method not only has high measurement accuracy, but also has the advantages of multi-azimuth dynamic measurement, which has a good application prospect in the field of motion parameters measurement of helicopter blade root.

For requirements of detecting, positioning and warning of sniper in sniping operation, the research of optical properties for gun flame and smoke was developed. According to the documentary data for gun flame and smoke and performance parameters of optical measuring equipment, a detailed field test scheme of optical properties for gun flame and smoke was designed. The optical properties for gun flame and smoke of a 5.8 mm and 7.62 mm caliber ballistic rifle were tested in the field. The test results show that the radiation of gun flame and smoke is mainly concentrated in 2 μm~5 μm, the duration was approximately 6 ms, the maximum radiation energy appears around 2 ms, and the radiation intensity of gun flame and smoke of 5.8 mm ballistic rifle is higher than 7.62 mm in both medium waves and long waves. The measurement results of optical properties for gun flame and smoke provide an important basis for the detection of gun flame and smoke and the improvement of weapon propellant.

Speckle correlation is the basis of speckle-based optical measurements and imaging recovery technologies, which determines the resolution of the opitcal system. At present, the theoretical description of speckle size (granularity or resolution) is not accurate enough and lacks of experimental verification. The influencing factors of speckle pattern autocorrelation size were explored, compared it with the same numerical aperture objective, and the scattering lens properties of thin scattering medium were revealed. Through the multiple sets of measurements for speckle autocorrelation and lens focusing size, the results show that the apodization function will affect the resolution, and the Abbe criterion needs to be corrected according to the specific optical path, which has a certain reference value for speckle-based measurement and imaging technology.

As the standard infrared light source, it is required that 30℃~420℃ blackbody can quickly heat up to the setting temperature, and keep the temperature stable. For the characteristics of large difference and large lag of heating and cooling power, the self-tuning method of impulse response based on the bang-bang control was used to obtain the parameters of blackbody temperature rise overshoot and maximum heating and cooling rate. Using the compound intelligent temperature control strategy, the temperature of 30℃~420℃ blackbody could rise speedily in the first stage. When approaching the setting temperature, the blackbody gradually reached and stabilized at the setting temperature. The experimental results show that 30℃~420℃ blackbody rises to the target temperature without overshoot, and the temperature stability is ±0.03 ℃/min, which reached the international level of similar products.

In order to reduce the inconsistency of spectral radiance caused by the aiming area differences between different spectroradiometers, the influence of field of view (FOV) angle and positioning on measurement accuracy was discussed. By establishing the spectral radiance measurement model of sunlight whiteboard and tungsten halogen lamp whiteboard, the differences between the average radiance and central radiance in the field of view of different geometric optical paths were analyzed. Numerical simulation shows that the correction factor of sunlight whiteboard path is only related to the size of FOV angle, while that of tungsten halogen lamp whiteboard path decreases with the increases of the measurement distance. When the distance is 600 mm, the correction factor of 8° and 14° FOV angle changes to 0.993 5 and 0.980 2, respectively. Finally, the experiment verified the influence of the angle error and displacement error on spectral radiance when using the tungsten halogen lamp whiteboard system. The results show that the correction factor presents asymmetry to the horizontal angle error and displacement error, and the difference between the two sides is as high as 2%. Therefore, the measurement results can be corrected according to the FOV angle and geometric positioning, which helps to improve the uncertainty level of spectral radiance measurement.

In order to measure the reflectivity of large-aperture and high-reflectivity optical elements in high energy laser transmission system, a precision measurement system for two-dimensional scanning of large-aperture optical elements was designed. The structure and working principle of the system were introduced, the factors affecting the measurement accuracy of the system were analyzed, and the influence of systematic error of the scanning system on the measurement accuracy was theoretically analyzed. The results show that the measurement error is 10⁻⁶ magnitude when the horizontal deviation is 0.29 mm perpendicular to the beam propagation direction. When the variation of cavity length is small, the rotation axis deviation can be compensated and the system can be fine adjusted by adjusting the ring-down cavity mirror. By fitting the data of light intensity and time, the corresponding first-order exponential function fitting curve was obtained, and the ring-down time as well as the reflectivity was obtained by calculation. Through contrast analysis, this kind of error analysis method can more effectively measure the reflectivity of cavity mirrors and can reduce the error brought by the experimental data itself.

To improve the calibration efficiency and accuracy of line structured light sensor, a plane checkerboard and concentric circle complementary line structured light calibration system was designed integrating with self-backlighting and pose-adjustable functions. Based on the geometric relationship between the real projection position of the concentric circle center and the center of projection ellipse, the nonlinear optimized compensation model for eccentric error was established, which precisely determined the eccentric error compensation position of the circle center under the perspective projection. Compared with the traditional calibration method, the proposed method reduced the re-projection error by 84.7% and effectively solved the problem of high-precision calibration for eccentric error compensation of circular markers. By combining the plane passing through the optical center and the center line of the light bar with the target plane in the camera coordinate system, the coordinate information of the spatial intersection lines was obtained for many times to increase the feature points, and the problem of lower calibration precision of plane fitting due to the fewer feature points was solved by using the least square method to fit the optic plane equation. In complex environments, the average error of the outer diameter of the large-size grinding wheel is 0.005 1 mm measured by repeated experiments, and the results show that the designed calibration system has certain precision, simplicity, and practicability.

To verify the influence of optical axis pointing error on optical attitude measurement accuracy and provide a theoretical basis for subsequent real-time equipment to realize attitude measurement, based on the central axis method, the algorithm steps were split, and the influence of optical axis pointing error was traced. It was concluded that the influence of pointing error on attitude processing results could be analyzed from two aspects. At the same time, the direct influence of the intersection algorithm in the model and the indirect influence of the dynamic reference outside the model were deduced and analyzed. Through the combination of simulation calculation and measured data, the conclusion that the pose angle error is no more than 0.1° in typical medium and long-term optical attitude measurement in the pointing error of 200" was obtained. It lays a theoretical foundation for the reliability analysis of the existing attitude measurement and the capability expansion of the subsequent range equipment.

Aiming at the influence of airborne panoramic video stream, a panoramic real-time splicing method based on embedded mode was proposed. The speeded up robust features (SURF) points in the image were extracted to generate the feature descriptors. The matching degree was determined by calculating the Euclidean distance between two feature points. After affine transformation, the Poisson transform was used to realize the fusion and smoothing between images. The above processes were executed concurrently on the target equipment, and customized optimization was carried out according to the characteristics of each process to realize the panoramic real-time splicing. After test, the proposed method realizes the seamless effect at the splicing joint, and the splicing speed reaches 30 Hz, which can meet the requirements of real-time display.

Gray method of tooth surface objects is one of the important methods to extract the gear interference image foreground region in laser phase-shifting interferometry. In view of the problem of limited measurement efficiency and limited accuracy caused by the manual threshold setting and neglect of different image edge features, a foreground region extraction method of gear interference image based on adaptive threshold was proposed. Firstly, the morphological characteristics of gear tooth surface and difference of each edge vertex were analyzed, and the image was divided into regions. Then, according to the changing rule of edge gray scale, the mask results were obtained by selecting qualified pixels through neighborhood window, so as to realize the foreground region extraction. Finally, the segmentation results of four groups of algorithms and traditional methods were compared according to five kinds of image evaluation indexes. The results show that the matching accuracy between the algorithm and reference results is improved by about 3.5%～4.5% based on the automatic image processing, the probabilistic rand index (PRI) is improved by about 3%～4%, the variation of information (VOI) is improved by 15%～25%, the global consistency error (GCE) is reduced by 2.5%～3.5%, and the final phase information accuracy is increased by 9 μm～15 μm. The results meet the requirements of accuracy, and the method can be widely used in foreground extraction of gear interference image.

Aiming at the problem that existing image deblurring algorithms based on convolutional neural network are not clear in the restoration of image texture details, an image deblurring algorithm based on multiple local residual connection attention network was proposed. Firstly, a convolutional layer was used to extract the shallow features. Secondly, a new multiple local residual connection attention module based on residual connection and parallel attentional mechanism was designed to eliminate the image blur and extract the context information. Moreover, a pairwise connection module based on dilated convolution was adopted to restore details. Finally, a convolutional layer was used to reconstruct the clear images. The experimental results show that the peak signal to noise ratio (PSNR) and structure similarity (SSIM) on GoPro data set are 31.83 dB and 0.927 5, respectively. Both qualitative and quantitative results show that the proposed method can effectively restore the texture details of blurred images, and the network performance is better than that of the comparison method.

Aiming at the problems of large amount of point cloud data, long registration time and low registration accuracy in the registration process of point cloud, a point cloud registration algorithm based on intrinsic shape signatures (ISS) and 3D shape context (3DSC) was proposed. Firstly, the down-sampling of point cloud was carried out by using a voxel grid filter. Then, the ISS algorithm was adopted to extract the feature points, which were described by 3DSC, and the rough matching was performed according to the improved random sample consensus (RANSAC) algorithm. Finally, the improved iterative closest point (ICP) algorithm was utilized to accurately match the point cloud. The experimental results show that compared with 3D normal distribution transformation (NDT) algorithm based on ISS+3DSC and ICP algorithm based on sample consensus initial aligment (SAC-IA), the proposed algorithm has higher registration accuracy and efficiency, and also has a better matching effect on point clouds with large data volume.