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研究了在实际应用中4 f 传像系统分辨率的影响因素及其作用机制，用于指导系统的设计和装调。首先，在理论上分析了由装调误差引起的像差对系统光学传递函数(MTF)产生的影响，并建立了描述二者关系的数学模型。基于该模型研究了1 μ m分辨率4 f 光学系统的装调误差，仿真计算了系统含有透镜偏心、倾斜、位移误差对MTF的影响，得到了分辨率随误差的变化曲线。实验结果表明，倾斜在15'以内，偏心误差在0.02 mm，位移在0.01 mm范围内，装调误差均会导致分辨率下降，虽然倾斜在极小范围内微调时分辨率会提高，但总的变化趋势不变。绘制的装调误差与分辨率的关系图，可为高分辨率4 f 系统的误差预估提供参考。

To measure infrared radiation characteristics of air targets, the calibration system for a 1 m aperture infrared measurement system was designed. A mathematic model of calibration for the infrared measurement system was given and a radiometric calibration system was established by combinations of a cavity blackbody and a collimator as the standard radiation source. Because the spectral response of the infrared measuring system is selective, the calibration principle based on conventional radiometric calibration method has theoretical errors and reduces the precision of radiometric calibration. To solve the problem, a relative spectral calibration method based on a monochromator and a standard radiometer was proposed. The mathematical model was given and a relative spectral calibration was performed. Finally, the experiments on radiation characteristic measurement were performed in the field by using the blackbody as a simulated target. The results show that the measurement max error from the 1 m aperture infrared radiation characteristic measurement system is 9.5% and improves by an average of 8.7% as compared with that of the conventional method. These show that the proposed method meets the requirements of practical applications and is suitable for the radiometric calibration in the out-fields.

This paper selected four major ecosystem services,biodiversity conservation,soil conservation,water conservation and nutrients conservation,to evaluate the ecosystem services of the Three Gorges Reservoir(TGR) area using GIS and RS techniques.We investigated the importance and spatial distribution of these services in a quantitative way.The results indicate that:(1) The percentage of the area with extremely and strongly important biodiversity conservation service reaches 15% of the total TGR area.The areas with extremely important biodiversity conservation present patchy distributions in the northeastern,central and southeastern parts of the TGR area;(2) The percentage of the areas with extremely important soil conservation is 68.80%.These areas are mainly distribute in Wanzhou and the regions northeast to Wanzhou;(3) The areas dominated by the slightly important water conservation service are widely distributed in the study region and are followed by those with extremely important water conservation service.The areas with extremely important water conservation service are located along the main streams,and the areas with moderately important water conservation service are distributed along the two sides of the main streams;(4) The areas with slightly important nutrients conservation service occupy the largest areas of the TGR area and are followed by those with extremely important nutrients conservation.The areas with extremely important nutrients conversation service are mainly distributed in zonal distribution along two sides of the rivers and streams,and the ridges;(5) The percentage of the areas with extremely and moderately important ecosystem services is about 50%.The areas with extremely important ecosystem services are distributed along the first watershed of main rivers and streams,and the ridges in the paralleled ridge-valley region in the west of the study region.The areas with moderately important ecosystem services are mainly distributed along the two sides of the above-mentioned areas and scatteringly distributed along the main streams.

A new wide viewing angle liquid crystal device was developed using PET technology.The liquid crystal molecule was twisted by double electric field.The rising time of the design with negative liquid crystal is slightly greater than the positive's,and the falling time is accordance with the positive liquid crystal.Compared with positive liquid crystal,the transmittance is increased about 10%.The relationship of transmittance with response time and voltage,was analyzed in the effect of three electrodes.The wide viewing angle technology monopoly of FFS and IPS was effectively solved.

To improve the understable imaging system caused by the high work frequency of image composing circuit on a satellite,the structure of a camera was innovated.A composion and compression method of Time Delay Integration CCD(TDICCD) based on a Field Programming Gate Array(FPGA) platform was proposed for satellite remote sensing data.The principle of real-time compostion and compression for multi-channel satellite remote sensing data was introduced.Then,based on the characteristics of TDICCD linear array push-broom imaging mode,the improved JPEG-LS was used.By taking adaptive quantization to control the coding rate dynamically,composion and compression of image data were simultaneously achieved on the FPGA.At last,an experiment platform was established for the validation.Experimental results indicate that the system clock has reduced to 80 MHz and 64 MHz,respectively,from the original 100 MHz in the lossless and 2-time compression and the Peak Signal Noise Ratio(Reconstruct PSNR) of the image is higher than 80 dB.As the proposed algorithm has low storage capacity,the average processing time of one line image is 57.5 μs,smaller than the smallest line period of the camera.The proposed algorithm is stable and the system is reliable and achieves the composion and compression of multi-channel TDICCD remote image within the camera.

Pr3+-doped 12CaO·7Al2O3(C12A7∶Pr3+) powders were prepared using the coprecipitation method and were characterized by XRD,excitation and emission spectra,fluorescence lifetime,afterglow decay,thermoluminescence and photostimulated luminescence.The emission peaks at 491,535,614 nm are attributed to the transition of 3P0→3H4,3P0→3H5 and 1D2→3H4 of Pr3+ ions.The long afterglow emission locate at 491,535,614 nm,the time of the afterglow emission is about 300 s.By fitting the thermoluminescence spectrum data,the depth of the trap is about 0.63 eV.After the samples were irradiated by UV light(230 nm) for 5 min and placed in the dark for 5 min to drain the afterglow,the intensive photostimulated luminescence(PSL)is observed under infrared excitation(808 nm) due to the existence of the shallow traps.Our results indicate that C12A7∶Pr3+ phosphor with three-wavelength phosphorescence and two-wavelength optical storage can be used in optical storage field as one kind of multi-dimension recording materials.

This paper gives a main structure of the display-control terminal equipment,and shows the function of virtual oscillograph and virtual meter by dynamic pictures switching and waves moving,which is based on programming of DSP.After the experiments on the vehicle,this system goes well and shows good performance of human-computer interaction.

A model and harmonic simulation analysis and experiments have been done separately by the finite element analysis software ANSYS and its first five natural frequencies,vibration models and the frequency response curve of rotating mirror were obtained.In the displacement frequency response curve of rotating mirror,the resonance bands of torsional vibration and bending vibration were overlapped,and the maximum peak value at the first bending vibration was greater than others.The stress of the first bending vibration was much larger than the others and the maximum stress appeared in the shaft.The main form of failure is the damage of the shaft,and the front bending vibration is the main reason of rotating mirror failure.With the model of rotating mirror natural frequency sensitivity compiled by ANSYS Parametric Design Language,the numerical analysis and experiment of rotating mirror natural frequency have been done using the Probabilistic Design System of ANSYS to study the interrelationship between physical dimensions and the natural frequencies.The numerical results reveal that the dependency of the circumcircle radius R5 of mirror body and the radius of shaft 2 with the same frequency is opposite,and the degree of correlation of R5 and R2 is higher than anther.The results of experiment show that the change mode and degree due to the same change of different structural parameters of rotating mirror is identical with numerical analysis.This study provides a quantifiable indicator for dynamic design of rotating mirror.