After comparing different structures of wide-angle projecting lenses, a wide-angle lens for 162.6 cm(64 in) rear projection laser display is designed. The focal length of the system is 7.38 mm, the wavelength used in the design is F, d, C and the full field of view reaches 100°. The technical indii of the projection lens are summarized as follows: DMD (Digital Micromirror Delice) is used in the light digital processing, 90% MTF is greater than 0.6 at the Nyquist frequency; the barrel distortion of the system is smaller than 1.4%,and 90% of the energy in the point target is focused in a pixel dimension. Furthermore,a right angle prism is used to fold the optical path to decrease the length of the lens,so that the whole optical length of the system is 259 mm after outspreading the right angle prism. The vignetting factor of the wide angle is negative, which enhances the image illumination after projection.Moreover, an aspheric surface with the small size, zero conic constant and the maximum eight order coefficient is used to promise the feasibility of the mounting. Analytical results show that the design can decrease the production costs of the projecting system and promote the technological industrialization.

To master the temperature distribution and "Solar cooker" of a Five-hundred-meter Aperture Spherical Radio Telescope(FAST) and to protect instruments in a feed cabin under the solar radiation, the temperature distributions of the FAST are studied in detail,which includes Sun parameters, "Solar cooker" calculation, heat flows and the temperature distribution of the FAST under different work conditions. The results indicate that the feed cabin temperature distribution is not only relevant to the reflector reflectivity, porosity rate, and the radiation time, but also to the reflectivity of the shield, materials, the diameter of microwave inlet and other factors. The analysis results of work conditions show that the reflector reflectivity is 0.2, porosity rate is 0.4 and the maximum temperature of the feed cabin is 47.56 ℃ at 12:00.Furthermore, the temperature of reflector surface reaches maximum 68.34℃ at 14:00, in which the minimum temperature is 35.03 ℃,and the temperature difference of reflector is 33.31 ℃. Moreover,the time domain of solar cookers is simulated.Finally,this paper gives the comments and suggestions for the design and use of FAST. The research in this paper not only obtains the temperature distribution of the FAST,but also provides references for the design and use of the FAST.

The fractal elements were exploited to design single layer Frequency Selective Surfaces (FSSs) as multi-band pass filters to meet the multi-band and integration requirements of the communication apparatus.Firstly, the geometry expression of a Y aperture fractal FSS with a symmetry structure and anti-cross polarization was proposed by recursion and iterative operations. Then, combined with Floquet theory and the full-wave periodic method of moment,an electric field integral equation to describe the current distribution of the FSS surface was obtained to quantitatively analyze the frequency response of the lattice and structural parameters of Y aperture fractal FSS, such as pole length, aperture width,and the different polarizations of incident electromagnetic wave. Finally,a FSS sample was achieved by the photolithography technology and experiments in the anechoic chamber. Experimental results show that the estimation empirical constant κ is 0.79 for designing the resonant frequencies of FSS and the bandwidth expands to 650 MHz when the width of aperture varies from 1.0 mm to 1.5 mm.Moreover, the effects of incident angle is highly sensitive to the lattice of the periodic unit cell. Obtained results are well coincident with that of theoretical calculation,which means the single-layer fractal FSS with multiband characteristics can satisfy the engineering requirements after parameter optimization.

To measure the coordinate of Center of Rotation(COR) for projection in an X-ray CT imaging system,calibrate the projection geometry coordinate system,and to eliminate the CT image artifacts caused by the positioning error of COR, this paper derives two lemmas based on the advantages and disadvantages of existing methods,i.e. ‘A particle is scanned a circle by a CT scanner, then The integral of the particle's projection addresses under each projection view equals to zero’ and ‘The sum of the crossing point coordinates of projection sine curves of random two particles equals to zero’. According to the above lemmas,an appropriate threshold is set to segment the sinogram to a binary image, the projection addresses of the rays penetrating the object are got based on the segmentation results and then the coordinate of COR for projection is obtained by calculating the mean of these projection addresses. The experimental results show that the method can measure the COR precisely and can improve the reconstructed image quality greatly.Moreover, the repeated measurement accuracy is less than 0.08 pixel. Compared with the existing methods, this method is simple and robustness and can meet the practical engineering requirements.

To improve the Photon Detection Efficiency(PDE), quantum efficiency and the dynamic detection range of a Multi-pixel Photon Counter(MPPC),its detection characteristics, especially photon number resolving capability were researched. By taking the MPPC as a photon detecting device and utilizing the Peltier effect and external trigger technology, the temperature of MPPC was controlled down to 15 ℃ and the dark counts of MPPC was reduced to 6.5×10-4 count/pulse.Then,by using the Poisson distribution the output signal of MPPC was fitted in the statistical method.Obtained results indicate that the intensity of laser pulses obeys the Poisson distribution. According to the PDE given in the datasheet, the energy resolution of MPPC was calculated.Furthermore,combined the energy resolution and intensity distribution, the average energy of laser pulses was obtained. The experimental results indicate that the MPPC has the energy resolution about 1.96×10-18 J in 532 nm and the average photon number of laser pulse after attenuation is 1.665 and 4.201, respectively. In conclusion,the MPPC is capable of photon resolving and suit for the ultralow light detection in a large dynamic range.

This paper describes the basic principle of multiple diffraction, including diffraction indexing and its intensity calculation, as well as the direction determination of the incident X-ray that meets the Bragg condition for two specific crystal planes. It proposes a X-ray energy calibration method based on the crystal multiple diffraction. In theory, this calibration method can reach a very high precision of 1 eV when the scanning step is 1″. To verify the feasibility of this method, a test is performed on the 14B diffraction beam line of Shanghai source,and the 180° Φ scanning diffraction pattern for the silicon(111) is collected at 10 keV. All the possible diffraction planes are set up and the glitch is indexed according to the angle difference of them. After indexing of the glitch, the calibrated energy of 10.06 keV is obtained. The experimental results are consistent with the theoretical results well, which proves that the calibration method can achieve a high precise calibration for photon energies when the angle scanning accuracy meets the needs of experiments.

In order to suppress the electromagnetic interference of a high-power TEA CO2 laser for the other electronic equipment, the near-field electromagnetic radiation characteristics of the laser were measured and analyzed, and an electromagnetic shielding cabin was designed and validated. According to the work principle of high-power TEA CO2 laser, the main electromagnetic radiation sources of the laser in working process were analyzed, then it points out that the main part of electromagnetic radiation tests is the spark switch, main circuit and the part of light out by combing of laser electromagnetic radiation theory and the actual structure. After analysis of test results, the main frequencies of laser radiation in different directions were obtained. Based on the above, the shielding cabin was designed, and its shielding effectiveness was verified near the cabin's door. The results show that the electromagnetic radiation of the high-power TEA CO2 laser is magnetic field source in the near-field zone, and the shielding efficiency is 40 dB for the whole frequencies and more than 60 dB for some special frequencies.

On the basis of biological visual systems and object recognition technologies, several key technologies of artificial compound eyes, including its structure, splicing, fiber coupling and optical signal receiving technique were studied and a bionic compound eye receiving system was designed for staring laser radars.By imitating the structures and shapes of compound eyes of insects,the system consists of 16 lens arrays,and its whole field angle is 2 °.The optical system was designed by the Zemax software and optical signals were received by fiber coupling technology.The detection results were studied experimentally,and it shows that this receiving system can well reflect the contour of detecting target,and the detection range is more than 200 m. On the experimental setup,a range image with 20 frames is obtained,and pixel space is 1.72 m×1.72 m. Obtained results verify the feasibility of proposed system and indicate that the system can be used in the missile end-guiding and the topographic matching of aerocrafts in low altitudes.

The disturbance estimation and compensation was introduced into close loop control systems to improve the low speed performance and disturbance rejected ability of photoelectric stabilized platforms. An original Velocity based Disturbance Observer (VDOB) was proposed and its characteristics were studied. The working principle of regular Disturbance Observer (DOB) was introduced and its drawbacks in applications to stabilized platforms were pointed out. By introducing a nominal model of stabilized platforms, the VDOB was established based on velocity signals, the structure of closed loop control system with VDOB was given, and its transfer behavior, disturbance rejected ability and robustness were analyzed. Finally, some simulations and experiments were carried out. Experiment results show that the PI controller with VDOB can overcome the speed creeping problem existed in traditional PI controllers when the platform does sinusoidal movement. Furthermore, the velocity disturbance isolation level of the platform after using PI controller with VDOB is increased by about 14 dB, Correspondingly, the stabilization precision of platform is increased from 0.03°(RMS) to 0.0044°(RMS) when the vehicle on platform is moved in sinusoidal manner at 1 Hz and 6.3(°)/s. In conclusion, the proposed VDOB is effective and valuable.

With the aim to realize Quantum Efficiency(QE) measurement of photon detectors based on Spontaneous Parametric Down-conversion(SPDC),two type of coincidence count systems were set up,the correction factors of coincidence count were analyzed and the real experimental methods of correction factors were given. Firstly, the principle of SPDC and the technique using SPDC to calibrate the QE of photo detectors was introduced. Then the design of two type of coincidence count systems, gated dual-photon counter coincidence count system and TAC/MCA coincidence count system,were introduced. Finally, the main correction factors, accidental coincidence, missing coincidence, dead time of counters and detectors were analyzed, and the calculation and test methods were also given. Experimental results show that the deviation between this two type of coincidence setups is less than 0.4% after correction, which indicates that the two setups can satisfy the requirement of QE measurement.

A novel force control method was proposed based on the Magnetorheological torque-servo (MRT) to control the polishing force to maintain a polishing pressure constant in precise NC polishing of aspheric parts. The mechanism, model and affect factors of the method were investigated,and a corresponding polishing system was developed. Firstly, the mechanism of the polishing force control method based on the MRT was presented. Then the principle of constant pressure polishing was analyzed by using Preston equation,and the model of polishing pressure was established according to Hertz theory. Finally, the control model of polishing force was deduced to realize the constant pressure polishing, and the affecting factors of model were discussed. Experimental results indicate that the surface roughness of the part improves from initial value 1.6 μm to 0.067 μm and 0.028 μm respectively, and the unevenness of surface roughness is 94.4% and 11.4%, respectively after polishing with the constant force and constant pressure and the polishing time in 90 min, which means the polishing quality and effciency have been improved greatly. It is concluded that the method can control the polishing force and polishing pressure independently, actively and real time and can improve the surface quality of parts remarkably.

In order to improve the surface precision of a thin primary mirror in a large aperture telescope at different altitude angles, the active correction procedure based on vibration modal calibration was proposed. For a thin primary mirror with the 620 mm in diameter, 18 mm in thickness and the axial munting in 36 points active support, the lateral mounting in 6 tangent points passive support, the free vibration mode of primary mirror was analyzed by finite element method and the first 10 vibration modes of the primary mirror were calibrated. Their RMS values were unified to 1 000 nm, also the calibration forces were calculated. Furthermore,the surface of the primary mirror with different altitude angles was analyzed, the deformations were fitted by the modal vibration mode using least square method, and the corrective forces were calculated. Finally the corrected surface precision and initiative surface precision were compared, and the fitted surface precision and remanent surface precision were analyzed after the second active correction. Corrected results demonstrate that the deformation (RMS) of the primary mirror is corrected from 27.64 nm to 12.95 nm while it is vertically positioned by using the maximum corrective force of 2.23 N, and it is corrected from 7.68 nm to 2.84 nm while horizontally positioned by using the maximum corrective force of 0.59 N. The simulation shows the algorithm using modal vibration to actively correct the primary mirror surface is feasible.

To achieve the stable and precise transfer of micro metallic powders in the laser microcladding fabrication,micro characteristics of micro metallic powder transfer, called pulse-transfer are studied based on a new principle of microfluidic drive and control, in which microfluidic flows are driven by the pulsed local inertia force in micro channels. By using this technique, the flow of microfluidics can be controlled in pulse (or digital) demands. An experimental system of pulse-transfer for micro metallic powders is built to determine influencing rules of four system parameters, voltage amplitude U, frequence f, the inner diameter d of micro-nozzle, and the angle of transfer θ, on micro characteristics (powder transfer rate and stablity) of irregular micro chromium powders. The system parameters are optimized according to the influencing rules for transferring irregular micro chromium powders, and the effects of powder transfer are experimentally investigated. Experimental results indicate that the pulse-transfer system has excellent micro characteristics, and its powder transfer rate Q is within a few ten μg per second and relative stadard deviation C·V for evaluating transfer stability is smaller than 7%. The transfer of micro metallic powders with greater stability and precision is experimentally verified by using the technique of microfluidic digitalization,which demonstrates that the research method can be applied to experimental and theoretical studies of micro powder transfer in different fields of engineering.

A flexible support structure was proposed to keep higher surface figure accuracy of space mirrors under gravity and uniform temperature change load cases. According to the optical design requirements, the structural form of a mirror was determined, and then a flexible support structure of the primary mirror was designed. By adopting finite element analysis software, the mirror component was analyzed and its structure was optimized. Analysis results show that the first order natural frequency of the mirror component is 179 Hz, and the surface figure accuracy RMS of the mirror reaches 5.06, 4.43 and 7.59 nm when gravity load is applied in the directions of X, Y, and Z axes respectively. Furthermore,the integrated surface figure accuracy RMS of the mirror reaches 6.08, 6.32 and 8.08 nm respectively under the load cases of gravity in three directions coupled with uniform temperature rise of 4 ℃. Laboratory test results indicate that the mirror can offer a good image quality under the condition of 4 ℃ uniform temperature change, the mechanical test results are consistent with that of the theoretical analysis and the change of the surface figure accuracy is not obvious after dynamic and thermal vacuum tests. Analysis and experimental results demonstrate that designs of the mirror and its support structure are effective, which can meet the requirements of space applications.

To improve the linear contour accuracy of 2X/Y gantry linear feed axes, the research of the literature focuses on the straightness accuracy measurement, evaluation and error compensation of the axes. Firstly, The cause of linear contour error in interpolation process and its compensation complexity were analyzed for a 2X/Y gantry feed axis driven by linear motors. Then a learning algorithm based compensation method was applied to increase the contour accuracy for this type of gantry axis.In proposed method, the 2D time function of a laser interferometer was utilized to acquire real-time interpolation error data and the least square method was taken to evaluate and determine the ideal linear equation. A model based on least square support vector regression technique was established to recognize the error. With the support vectors after learning process, the real-time compensation values were acquired through the model regression calculation. Finally, the compensation output strategy and corresponding realization system were also proposed. To demonstrate the procedure of the proposed approach, an experiment was conducted on the self-construction 2X/Y axis feeding platform. The result shows that the combination technique can compensate the interpolation error and can increase the straightness accuracy by 53%.

A calculating model based on difference method was proposed to calculate the image motion velocity vector to campensate precisely the image motion of a space camera. Firstly, the earth imaging model was established by utilizing coordinate transformation,and the relative motion between the image point and the image plane was analyzed in vertical, roll and pitch attitudes according to the states of the image motion. Then, a method was proposed to calculate the image motion velocity vector according to the law of the relative motion between the image point and the image plane. Finally, the proposed method was compared with the coordinate transformation method. The result shows that the error between the two methods is within 0.1%, which proves the efficiency of this method. The proposed method overcomes the complex compulation from traditional methods and can be used in calculating the image motion velocity vectors for other space cameras.

In order to improve the precision of Nonplanar Four Mode Differential Laser Gyros (NFMDLG), a compensation method by using reciprocal biasing is proposed. Expressions of reciprocal biasing and bias of the NFMDLG are derived according to the classic theory of a gas laser. The bias characteristics of the left circularly polarized gyro in the NFMDLG on the left and right sides of a gain curve are analyzed for two cases, respectively. Then,it points out that the bias caused by a magnetic circular dichroism loss is identical in number while reverse in sign for the two cases. An experimental system is established to measure the reciprocal biasing and bias synchronously,which verifies the theoretical analysis by varying the discharge current and temperature. Finally,a method is proposed to compensate the bias error of NFMDLG with reciprocal biasing. Experiments show that the bias drift resulted from temperature variation in the range of 10-60 ℃ is less than 0.01 Hz,and that resulted from 0.2 mA current variation is reduced by four-fifths after compensation. In conclusion,the reciprocal biasing can compensate effectively the bias caused by the mode pulling effect.

The structure of detecting electrodes in a conductivity detector was studied to decrease the effect of the stray capacitance between the two electrodes on the detecting signal in capillary electrophoresis. The boundary element method was used to study the stray capacitance of two electrodes in contactless conductivity detection. Then,an electric field software was taken to simulate the electric field distribution of electrodes and to optimize the electrode structure with contactless conductivity.On the basis of simulated results,a novel sandwich electrode structure was proposed to decrease the direct capacitive coupling between the two electrodes. The effective length of the electrode is 200 μm,which decreases the stray capacitance between the two electrodes and overcomes its defect to be easy to breakdown. The experimental and simulation results indicate that the stray capacitance of proposed electrode structure is obout 10-5 F,which has been decreased about one order of magnitude as compared with those of conventional electrode structures. Moreover, two inorganic cations can be separated in 40 s at 220 V/cm separation voltage. In conclusion,the sandwich electrode structure is suitable for the contactless conductivity detection and improves detection sensitivity.

The angular momentum flywheel subsystem of a Single Gimbal Control Moment Gyro(SGCMG) was designed to improve the attitude control accuray of satellites. Firstly, the impact of angular velocity fluctuations on the output torque of SGCMG was analyzed in theory. The conclusion suggests that when the expected speed is 5 000 r/min and the torque fluctuation is less than 0.002 Nm, the angular velocity fluctuations should be less than 5 r/min. Then, the angular momentum flywheel was driven by a Brushless Direct Current Motor(BLDCM), the control driver circuit was designed by a Field Programming Gate Array(FPGA),and an adaptive compensation PI control strategy was established to track the expected angular velocity. Test and experiments show that it takes 25 s to reach a steady-state from stillness to 5 000 r/min,the overshoot is less than 15 r/min and the steady-state accuracy is 2 r/min. Analysis of the data collected real-time by PC shows the rationality of the subsystem and indicates the angular moment wheel designed satisfies the requirement of the SGCMG, reduces the impact of angular velocity fluctuations on the output torque of SGCMG,and improves the platform control accuracy of satellites.

On the basis of target acquisition, recognition and visual blurring, a novel method by using a single camera as a monocular measurement system was presented to overcome the effect of matching of feature points and extraction errors of a single feature point on the measuring results. The principle of monocular vision measurement for target distances based on the feature points was introduced. Firstly, it sets up the mapping relationship between image points and target points according to the pinhole imaging principle, then also describes the area mapping relationship between the object area and the image area of an object by analysis of the object image, and establishes the model of line distance measurement. Finally, the distance measurement between optical center and target was transformed into that between optical center and feature points by processing images and extracting feature points. The proposed measurement principle was verified experimentally. Based on the measuring error increased with the measuring distance, it analyzes the error sources and corrects obtained data. Results show that thelargest error ratio has is 1.68%, as compared with that of 6.72% from the reference 12,both the feasibility and effectiveness of the proposed principle are proved.

A circuit design method was proposed to compress the space of circuit in a photoelectric encoder and to reduce its size, then the signal processing of the circuit was studied. The basic principle, signal characteristics and signal processing requirements of the photoelectric encoder was introduced and the characteristic of traditional process circuit was analyzed. It points out that the traditional scheme based on amplifiers and comparators is the reason that the circuit structure is larger. To improve the traditional scheme, the methods of A/D through processing and time sharing driving photoelectric signal acquisition were proposed to replace the traditional hardware scheme to compress the space of circuit. The design principle of high integrated circuit of encoder was explained, then a 16-bit smaller encoder with the circuit board area of 415 mm2 and the volume of Ф25 mm×16 mm was designed. Obtained results demonstrate that the circuit design technique for high integrated photoelectric encoders based on SOC single-chip is a better way to compress the circuit space, for it has fewer components, simple circuits and higher integration.

In order to predict the variation of inductive crosstalk of the cable bundles as the automobile was in motion, both the prediction model of the inductive crosstalk best/worst cases and the amended model by Monte Carlo method were established. According to the extreme position of wires in cable bundles, the prediction interval of the inductive crosstalk best/worst cases was defined. By using the Monte Carlo method the mathematical expectation of the inductive crosstalk was obtained, and the confidence level for the expectation was defined under the circumstance of 80% confidence level. Here, the confidence level was the amended prediction interval. By comparison with the results from EMC Studio electromagnetic simulation software, it is shown that the cable bundle crosstalk in all selected positions are in the best/worst case interval and most of them are in the amended interval when the frequencies are lower than 5 MHz.The length of the amended interval has decreased by 40%. Moreover,the electrical dimensions tend to electrically large and the error also increases when the frequencies are higher than 5 MHz.It concludes that the both models are simple and convenient to predict the inductive crosstalk rapidly according to different accuracy requests.

To overcome the influence of the nonlinear friction on the gimbal servo-system of a double gimbal control moment gyro with harmonic drivers,the methods of modeling and compensation of the nonlinear friction are proposed. Firstly, the nonlinear friction torque and the angle acceleration of a gimbal motor and the relationship between the friction torque and the current of the gimbal motor are deduced according to the mathematical model of gimbal servo-system. Then, based on the angle position measured by encoders, the angle velocities of the motor and loader sides are calculated and an angle acceleration estimator is designed to estimate the angle accelerations of the motor and loader sides. Furthermore, the nonlinear friction torque is calculated and modeled as the Coulomb, viscous and Stribeck friction model. Finally, a feedforward compensation controller based on the model is designed to restrain the nonlinear friction and to improve the control precision. Experimental results indicate that compared with those of the conventional PID control method, the peak-peak value of angle velocity error curve has decreased by 28.2% and the mean squared error decreased by 25.7% after the feedforward compensation controller is added. It concludes that the feedforward compensation controller decreases the angle velocity error caused by nonlinear friction and improves the control precision of the servo-system.

The sucking outflow phenomena of a passive piezoelectric pump under the square wave driving is studied and, a hydrodynamics model and a vibration model of passive piezoelectric pump are built to analyze theoretically the physical process of the sucking outflow process.Then,an open height formula of the existing valve in sucking processing is derived. The open height of the piezoelectric pump is measured during the sucking outflow process under different frequencies of 0.4,0.8,6,45 Hz, and the other factors effecting on the sucking outflow in the formula are verified. In the theoretical analysis,it points out that the flow inertia is the root cause for the outflow sucking phenomena, and the inertial flow also exists during the draining process. The experiment indicates that when the piezoelectric frequency increases, the open height of the output valve during sucking process decreases. When the exiting valve rigidity and the loadings in input and output increase, the outflow decreases.The results above are coinciden with the formula well. It concludes that the output flow of the piezoelectric pump should include two parts: cubage flow and inertial flow, which should be considered in the same time when the flow of the piezoelectric pump is controlled precisely.

An adaptive smoothing algorithm within a scale space framework is proposed to extract the features of noisy range image of a laser rangefinder. The method is composed of feature estimation and multi-scale smoothing. A Unscented Kalman Filter(UKF) is used to construct an adaptive feature estimator to estimate the topology of points,then the Mahalanobis distances obtained by estimation are taken to calculate the smoothing mask. In order to provide a more efficient estimation of different major geometries by a single model, an adaptive curve model which varies depending on the local nature of range image is employed. Experimental results indicate that the Peak Signal-to-Noise Ratio (PSNR) gain of the adaptive algorithm has reached 10.55 dB and the Mean Square Error(MSE) has been reduced by 58.24% when the noise variance is 2.25×10-4 m2. The proposed method with a adaptive model can improve the correctness of feature extraction by 10% comparing to the smoothing algorithm with a fixed neighborhood model, while the time consuming is reduced by about 55%.

As the serious lead deviation of the radar will effect on the tracking ability of ship-based optoelectronic equipment a new controlling algorithm combined the semi-automatic searching and TV tracking is provided based on inertial navigation platform and apply to a optoelectronic searching and tracking system.The algorithm is mainly divided into two steps.Firstly the artificial mode turns into a auto-searching when the deviation of guide exceeds the current scene under the course of radar leading.Sencudly when the extration threshold of the image is satisfied for the contrast of the target in the searching scene, the speed computed by using the CA model Least Square Method feeds back to the speed loop, and then combines the TV information to accomplish the closed-loop control of TV tracking. The algorithm is verified by a experiment the Experiment show that the target capturing distance is 16.4 km on the great lead deviation by using the algorithm,which is highter 11 km than that by using the traditional algorithm. The algorithm can implement the semiauto matic searching and tracking,and can reduce capturing and tracking time,improre the optoelectric count measure ability when the lead deviation of the radar is great.

A camera calibration method based on the flexible spliced two-dimensional target is proposed to orercome the problems in the camera calibration that a large scale target with high precision is hard to fabricate, and the smaller one cannot satisfy the required accuracy. According to this problem. The flexible spliced two-dimensional target consists of many small planar targets (called sub-target). Each sub-target includes a matching area and an extending area. Those sub-targets are combined into a virtual large scale planar target (called mother-target) by encode in the matching area and the camera parameters are calibrated by the mother-target. Simulation and real experiment results indicate that the accuracy of the proposed calibration method is almost the same as that of Zhang’s calibration method using a large planar target with the point numbers similar to that of the flexible spliced two-dimensional target. The relative error of the calibration result of them is less than 2%. This method shows his advantages in that the target is convenient to be fabricated, and the area of target can be extended infinitely.

As the Non-negative Matrix Factorization (NMF) algorithm has a higher iteration time complexity and the Gradient Projection(BP) optimization method can significantly reduce the NMF iteration time complexity, an image fusion algorithm by combiing the improved PGNMF and Nonsubsampled Contourlet Transform (NSCT) is proposed in this paper. Firstly, the reistered oriinal images are decomposited in multi-scale and multi-direction decomposition in NSCT domain. According to the characters of the different areas, different fusion rules are designed in the NSCT domain. The low-pass sub band coefficients used as original data impose to the IPGNMF algorithm,to obtain the fused low-pass sub band coefficients and the band-pass directional sub band coefficients impose to the Neighborhood Homogeneous Measurement (NHM) algorithm,to obtain the fusion band-pass directional sub band coefficients. Finally, the fused result is obtained through inverse NSCT. The propose algorithm has been experimented on two groups of different scene images,and experimental results show that it superior to those conventional fusion methods based on NSWT,IPGNMF and NSCT in subjective and objective standards.As contrasted with NSCT method in two groups images, its entropy, definition and QABIF have been increased by 0.0627%、0.901%、3.1201% and 2.769%、2.203%、1.049%,respectively。

The thermal characteristics of ball screws in servo systems were analyzed,then a simplificated temperature filed model was established to predict the temperature distribution and variations of the ball screws quickly and accurately. The simplified model can predict the unsteady temperature rising of the ball screws, however, there are big errors when the model was used to predict the steady temperature variations of the ball screws. A new simplified model was built by introducing the factor of time modification in the simplified model. The new model has a good performance in predicting the process of steady temperature, however, there exist big errors when the new mode was used to predict the unsteady temperature rising of the ball screws. Based on the performance of the two models abore, a new interval model was also built and the parameters of the new interval model were identified by the LS method. The results show that the error of temperature prediction is less than 0.5 ℃ for a single thermal source, and less than 0.8 ℃ for the double thermal sources.It concludes that the interval model built in the paper has good performance in prediction the temperature variations of ball screws.

For the problems of low motion estimation accuracy and affecting easily by various interferences an improved optical flow algorithm with five-confidence-point restraint based on gradient thresholds was put forward in this paper.The five-confidence-point weighted method was applied to calculate the time and space gradient values of each image pixel and to reduce the effect of noise on the single pixel, and the gradient threshold was adopted to process the basic optical flow constraint equation.Therefore, the interference data which will disturb the motion estimation in the optical flow field were eliminated and the motion estimation accuracy of motion image was improved. The experiments were carried out by the traditional algorithm and the improved one, respectively for global and local movements. The contrastive analysis shows that the improved optical flow algorithm can figure both scene global motion and local motion in the scene and has advantages of high motion estimation accuracy and strong anti-interference, better robustness and convergence as compared with that traditional one.Furthermore,it can the shorten computation time by 1/3. It can be expected that this algorithm have potential application in driving environment sensing and traffic flow analysis.

In order to overcome the wave-front distortion caused by atmosphere turbulence and optical system aberration, the Phase-Diverse Speckle (PDS) method was used to collect simultaneouslly two or more short-exposure optical images formed by focusing or defocusing to estimate both the object and the wave-front phase.To verify the improvement of image resolution and phase estimation of PDS method,A comparison experiment on high-resolution imaging and phase estimation comparison was carried out based the PPS method and a Shack-Hartmann sensor. By shifting the high accurate translation stage at a certain distance,the focusing and defocusing images were obtained,then the wavefront phase based on the image was camparied with that from the Shack-Hartmann sensor. Experiment results indicate that the estimated wave-front phase is highly according with that detected by Shack-Hartmann and the resolution of the restored image can increase by 12% compared with the origin image formed by focus plane. In conclustion, the proposed method can be used to restore the degradative images in large aperture telescopes.

To solve the problem brought by high dimensionality of multi-spectral images during color reproduction, a nonlinear dimensionality reduction method for multi-spectral images was presented. Firstly, according to the characteristics of human visual system, the CIE standard observer color matching functions were weighted to the source spectral reflectance and a Principal Component Analysis (PCA) method was used to the weighted spectrum to effectively improve the colorimetric precision and color difference stability of dimensionality reduction. Then, for the spectral reflectance loss caused by weighting color matching functions, a PCA method was imposed on the lost spectrum to compensate the lost spectral accuracy caused by the improvement of colorimetric precision to effectively improve the spectral precision of dimensionality reduction. Finally the principal components obtained from the first two steps were combined to form the low-dimensional spectral data. Experiments show that the proposed method can offer the average spectral precision in 0.013 9, average colorimetric precision in 0.705 8, and the color difference stability in 1.950 6,which is increased by 14% and 15%,47% and 68%,as well 84% and 82% as comparied those of the PCA cand LabPQR methods. The method outperforms the existing methods in the colorimetric accuracy, spectral accuracy and color difference stability under different illuminants.