【作者】 陈嘉佳；

【导师】 黄战华；

【作者基本信息】 天津大学 ， 光学工程， 2007， 硕士

【摘要】 随着科学技术的巨大发展,人们对信息的需求与日俱增。图像作为信息传递的重要载体,在航空、军事、生物医学、天文气象、地理、工业以及农业等人类生活各个方面广泛应用,它在人们生活中的作用不可取代。但是由于各种环境及其它因素的制约,如典型的热源辐射空气环境,不可避免地会带来图像的失真和变形。本文在实验和理论分析的基础上,对热源辐射空气环境下变折射率介质中的光学成像影响进行分析研究,获得了光学成像变形的规律和幅度,利用统计计算和数字图像算法对图像进行补偿。本文的主要工作包括以下几个方面:通过非均匀介质中的光学理论分析,得到非均匀介质光波传播的基本公式和传递函数。完成了球形空气团模型和变折射率空间光线追迹算法,求出了的空间成像变形,理论计算与实验的相符,为变折射率空间成像分析奠定了基础。研究了有无热源辐射的情况下图像变形现象,确定了图像变形的总体分析方法,得到了图像变形的总体规律。采用高速摄像仪和高像素数码相机进行了热源辐射环境下空气折射率分布变化引起光学成像变形的实验研究,获得了成像变形随时间、热源温度高低、热源距离远近变化的影响规律。根据大量的实验计算和相关理论分析获得的变形规律和幅度,通过统计计算和图像处理方法进行了图像位移和畸变的补偿,提高了图像的质量和测量精度。更多还原

【Abstract】 With the development of the science and technology, needs of the information is growing day by day. As an important carrier of information, images have been used widely in many fields and can’t be replaced, such as aviation, military, biomedicine, astronomy, geography, industry, agriculture and so on. But some image distortions will inescapably occur by different environmental factors and others. Based on the experiment, Research of image distortion caused by the change of the air’s distribution of refractive index in a thermal radiation field has been performed. It shows that the optical image characteristics can be gathered by calculation and the image can be reconstructed by image processing.Some researches in this dissertation have been carried out as the following:A basic equation and a transfer function of light-wave transmission in the m non-uniform medium are educed based on the Fourier optics– Eigen wave function expansion theory of space electromagnetic field distribution. It shows conformity comparing the actual image distortion with the theoretic image distortion which is calculated by the light-tracing algorithm based on the globular air mass model.Based on the research of image distortion comparing the image in the thermal radiation field with the one not in, the general method of the analyses is determined and the characteristic of displacement of image distortion is got.Research of image distortion caused by the change of the air’s distribution of refractive index in a thermal radiation field has been performed by the high-speed camera and the high-element camera. It gets the influence on imaging which is changed with the time, the temperature and the distance of thermal radiation field.According to the research on the image distortion in a thermal radiation field. It shows that the optical image characteristics can be gathered by calculation and the image can be reconstructed by image processing. Thus, the image quality and measurement accuracy have been improved.更多还原