Abstract:建立了圆柱形激光晶体的热传导模型.通过求解泊松方程,得到了在不同Nd离子掺杂浓度和不同泵浦光半径情况下激光晶体内的温度和温度场分布.研究结果表明,当其他条件不变时,随着Nd离子掺杂浓度的增加,Nd∶YAG晶体端面中心温度会升高,而晶体中心轴温度却会快速衰减.对于相同晶体,在泵浦功率一定时,随着泵浦光斑半径的减小,Nd∶YAG晶体端面中心温度会升高.如果采用低掺杂浓度的晶体作为增益介质,同时合理增加泵浦光斑半径,则可以有效抑制晶体的热效应.这一结论为提高激光器的稳定性、研究晶体的热效应提供了理论依据.

Abstract:The distribution characteristics of infrared images of liquid-layers in etching process of semiconductor are studied. Through the processing of infrared images, characterization of thermal convection between liquid-layers at any time is realized. The chemical reaction occurred in the etching process of semiconductor can result in energy release and absorption which can cause the exchange of energy between liquid-layers, and hence lead to the change of etching temperature. This characteristic can be monitored by an infrared thermal imager in real time and thus the basis can be laid for the further analysis and characterization of thermal convection of liquid-layers. Experimental results have shown that the closer the location to the interface of semiconductor material with the etching liquid, the more remarkable the temperature change of liquid-layers is. Moreover, the temperature is decreased in a gradient form from internal area to external area around the semiconductor material. The thermal convection of horizontal liquid-layer is obviously quicker than that of the vertical liquid layer. The extracted infrared cross-section image can clearly characterize the temperature changing characteristics of the horizontal liquid-layer and the vertical liquid layer. The method is of important value to the analysis of thermal convection information of liquid-layers at any time.

Abstract:A thermal conduction model of cylindrical laser crystals was established. The temperature distribution in the laser crystals with different Nd concentration and different pumping radii were obtained by using the Poisson equation. The study result shows that with the increase of Nd ion concentration, the central temperature at the end of the ND : YAG crystal will rise and the temperature at the central axis of the crystal will decrease under the same condition. For the same crystal, when the pumping power is given, the central temperature of the Nd : YAG crystal will rise. If a lower ion doped crystal is used as the laser midium and the pumping radius is increased rationlly, the thermal effect of the crystal can be restained. The conclusion has provided a theoretical direction for the improvement of the stability of lasers and the study of the thermal effect of crystals.

Abstract:本文在研究45°扫描镜地面像元变化过程的基础上，对45°镜多元并扫像元变化特征和扫描轨迹进行了分析，给出了扫描轨迹计算式。讨论了像旋对地面分辨率的影响，分析了系统是否存在漏扫的条件，得出了不漏扫遥感器扫描参数需满足的条件。

Abstract:Based on the study of imaging changes of a 45?rotating scanning mirror on the ground, the imaging characteristics and scanning traces of the 45?rotating scanning mirror are analyzed and the calculating method of the scanning trace on the ground is given. The influence of image rotation on the ground resolution is discussed, the missing scanning condition of the system is analyzed and the condition which the remote sensor should meet to avoid missing scanning is provided.

Abstract:美国洛斯阿拉莫斯国家实验室的科学家开发出了一种新颖的全内反射红外显微分光成像方法。这种新颖成像方法的成像面积和采集时间要比现有的商业衰减全反射（ATR）系统大得多和快得多。其测量速度比现有的采用内部反射元件的商业系统快10倍，可达到的图像尺寸则要比采用焦平面列阵的ATR方法所能达到的图像尺寸大20倍。

Abstract:A method for evaluating the infrared signatures of decoys by using small patches and entropy is proposed. Firstly, a small patch method is used to segment the image patches with high values, then the image matching probability is calculated and the evaluation standard is determined by using entropy, and finally the effectiveness of the decoy is evaluated. The higher the matching probability between the real target and the decoy is, the greater the similarity of them is and the better the effectiveness of the decoy is. This method can eleminate the error in image information extraction very well.

Abstract:Firstly, the status, function, challenges of airborne radars in modern wars are presented and the infrared signatures of all parts of an airborne radar are further analyzed. Secondly, how the airborne radar confront the point-type infrared missile is studied emphatically. Finally, the relationship of the launch time of an infrared decoy with its sustained time in two different launch ways is obtained. This can provide the theoretical basis for the airborne radar to confront the point-type infrared missile.

Abstract:Penetration of the ballistic missile in infrared wavebands is achieved mainly by controlling the infrared signatures of its warhead and by implementing infrared jamming to the interceptors. After these measures are adopted, the ballistic missile will be not easy to be detected by interceptors and its penetration in infrared wavebands will be achieved succesfully.

Abstract:In this paper, the beam characteristics of semiconductor lasers are studied and their far-field images which are the Fourier transform of near-field images are analyzed and deduced. The semiconductor laser beam has a bad directivity and its divergence angles in the fast and slow axes have a large difference which can causes the beam spot emitted by the semiconductor laser to be elliptical. This is disadvantage to its transmission in a long distance, so the collimating technology of the laser beam is also studied.

Abstract:系统地研究了Er3 :Yb3 共掺磷酸盐玻璃波导的性质,在稳态情况下建立并求解速率方程.利用数值分析的方法模拟了980nm二极管激光器抽运时激光器的放大自发辐射(ASE)特性.模拟时用到的主要参数为:信号光的散射损耗α(1530)=8.2×10-2 dB/cm,980nm时Yb3 的吸收和发射截面积分别为5.4×10-25m2和6.9×10-25m2,980nm时Er3 的吸收和发射截面积分别为1.65×10-25m2和1.21×10-25m2,Yb3 Er3 间的能量传递系数为1.9×10-23m3/s

Abstract:Laser modulation techniques have been widely used in laser displays. In this paper, the operation principles and development status of various modulation techniques are presented, compared and analyzed.

Abstract:The purpose of this paper is to discuss the method for evaluating sleep quality by using the Thermal Texture Maps (TTM) and its application value. The sleep quality of 281 cases were evaluated and the results were compared with the detail statement records of patients. As a result, among 281 cases, 119 cases of sleep disturbance were found by the TTM technique and 122 cases had the detail statement records of sleep disturbance. The pick-out rate is 97.5%. So, it is concluded that the evaluation of sleep quality by TTM is simple, easy and accurate and has a apparent practical value to diagnosis.

Abstract:宇航工业需要把高光谱分辨率和大空间信息量结合起来的傅里叶变换光谱仪(FTS).依靠三十多年的经验,加拿大ABB公司(前身为Bomem公司)报以成像傅里叶变换光谱仪.

Abstract:一、探测器技术 1.集成焦平面列阵技术在激光微型卫星网络中的使用(Shlomi Arnon)