针对序列图像中目标因不显著、被遮挡等情况而出现的虚警或丢失问题，提出一种基于自动选取辅助目标的建筑物目标间接定位方法，提高目标跟踪稳定性。该方法首先自动选取红外图像中形状稳定、灰度显著的区域作为辅助目标。定位建筑物目标后，提取其与目标相对位置关系,之后利用该相对位置间接定位，最后融合直接识别及间接定位结果定位目标，并能实时更新辅助目标，保证其时刻处于视场中。实验结果表明：通过间接定位能解决目标虚警或丢失问题，提升目标定位过程中算法的准确性及鲁棒性。

目前太赫兹技术的研究主要集中在它的产生、探测机理研究上。由于太赫兹波处于微波和可见光之间的频率范围，已有的微波和光波理论是否能适用于太赫兹波或者具有某些共同的特性仍需实验验证。通过实验分析验证了太赫兹波在空气介质中在垂直于传播方向的平面内场振幅是服从高斯函数分布的，测量给出了太赫兹波的能量分布图。根据测试数据推导出太赫兹波在空气介质中能量衰减公式，利用法布里珀罗(F-P)干涉仪原理设计出太赫兹波长仪，对美国Corehent公司SIFIR-50 THz太赫兹激光器发射的1～3 THz波长进行了测量。讨论分析了远场发射角、光束入射角度、机械振动、温度波动和折射率n波动等相关因素对测量精度的影响。

研制了一种下一代小型化实时成像的激光雷达样机，这种新的激光雷达系统由激光二极管、准直镜、MEMS微扫描器、收集光学、带通滤波器、光电探测器和信号处理装置组成，其核心器件是基于MEMS的微扫描反射镜。详细分析了系统的结构和参数，结果表明：其距离分辨率为1cm，视场角为24°，谐振频率为1.5kHz。该下一代MEMS微扫描器激光雷达系统具有高精度、低成本、小体积和三维实时成像等优点。

A novel hybrid fitting energy-based active contour model in the level set framework is proposed. The method fuses the region and boundary information of the target to achieve accurate and robust detection performance. A special extra term that penalizes the deviation of the level set function from a signed distance function is also included in our method. This term allows the time-consuming redistancing operation to be removed completely. Moreover, a fast unconditionally stable numerical scheme is introduced to solve the problem. Experimental results on real infrared images show that our method can improve target detection performance efficiently in terms of the number of iterations and the wasted central processing unit (CPU) time.

We propose improved multilevel filters (IMLFs) involving the absolute value operation into the algorithmic framework of traditional multilevel filters (MLFs) to improve the robustness of infrared small target enhancement techniques under a complex infrared cluttered background. Compared with the widely used small target enhancement methods which only deal with bright targets, the proposed technique can enhance the infrared small target, whether it is bright or dark. Experimental results verify that the proposed technique is efficient and practical.

A novel indirect building localization technique based on a prominent solid landmark from a forward-looking infrared imagery is proposed to localize low, deeply buried, or carefully camouflaged buildings in dense urban areas. First, the widely used effective methods are applied to detect and localize the solid landmark. The building target is then precisely indirectly localized by perspective transformation according to the imaging parameters and the space constraint relations between the building target and the solid landmark. Experimental results demonstrate this technique can indirectly localize buildings in dense urban areas effectively.

A joint clustering and classification approach is proposed. This approach exploits unlabeled data for efficient clustering, which is applied in the classification with support vector machine (SVM) in the case of small-size training samples. The proposed method requires no prior information on data labels, and yields better cluster structures. Through cluster assumption and the notions of support vectors, the most confident k cluster centers and data points near the cluster boundaries are labeled and used to train a reliable SVM classifier. Our method gains better estimation of data distributions and mitigates the unrepresentative problem of small-size training samples. The data set collected from Landsat Thematic Mapper (Landsat TM-5) validates the effectiveness of the proposed approach.

A 128×128 elements cylindrical liquid crystal (LC) lens array with electrically controllable focal length is proposed. The cylindrical LC lens array uses transparent indium tin oxide (ITO) films as electrode, avoiding to affect the optical path operating in the voltage-off status. As the top electrode of the cylindrical LC lens array contacts with LC, the operation voltage root-mean-square (RMS) amplitude can be as low as 1.4 V and the response time is about 20-30 ms. The special optical focusing feature of the cylindrical LC lens array is got. And the focal length of this array is about 60-450 \mu m.

理论上分析并从实验上验证了通过改变外加电场的频率来驱动的128×128元变焦液晶透镜阵列。将上电极设计为圆孔阵列,由于圆孔电极在单元区域内形成的非均匀电场分布,从而使液晶分子在不同位置处旋转角度不同,在液晶层内形成了折射率梯度分布,由此单元区域具有了光学聚焦特性。分析了由于外加电场频率改变引起液晶介电常数变化给液晶透镜阵列焦距带来的影响。实验中制作的液晶透镜阵列的焦距调节范围为20-600 μm,焦点尺寸为10 μm,响应时间为微秒量级,可以呈清晰的多重影像。通过使用外加电场的频率可以得到变焦液晶透镜阵列,降低了液晶透镜阵列的工作电压,提升了液晶透镜阵列工作响应速度。