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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.

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.

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.