【毕业论文】大气对激光的吸收特性研究论文.docVIP

湖北汽车工业学院本科毕业设计（论文） PAGE I 毕 业 设 计（论 文） 题 目： 大气对激光吸收特性的研究 系 别： 理学系 专 业： 光信息科学与技术 班 级： 学生姓名： 学 号： 指导教师： 摘 要 自1960年第一台激光器问世以来，激光在航空、军事、医学、生物工程等领域得到了广泛的应用，激光技术的研究也越来越受到人们的重视。大气作为激光传输中最常见的介质，对激光具有强烈的吸收作用，这是激光技术的应用基础理论。本文通过分析大气层结构以及大气对激光的吸收、散射、折射等特性，设计了大气对激光吸收特性的实验，研究了激光在大气中的传输，并利用朗伯吸收定律计算了大气对激光吸收的粗略定量规律。实验结果表明激光在大气中传输时，光强变化符合指数衰减规律。由于不考虑激光在大气中传输时所发生的重要色散现象，可认为衰减系数近似等于吸收系数。因此，测得粗略的吸收系数为1.33129m-1，这表示激光强度大致以每米1.33129的指数形式衰减。研究还表明吸收系数越大，吸收明显增强。 关键词：激光技术；大气特性；吸收系数；传输规律 Abstract Since the first laser was invented in 1960, lasers had been widely used in some fields such as aviation, military, medical and biological engineering and so on, and the research for laser technology had also captured more and more people’s attention. The atmosphere as a normal media for laser transferring absorbs laser energy violently, which acts as the basic application theory of laser technology. By analyzing the configuration of atmospheric layers and the characteristics of atmospheric absorption, scattering, refraction of lasers and so on, the paper designs experiment on atmospheric absorption characteristic of laser at first, and then studies laser transferring in atmosphere, finally calculates the coarse quantity rule of atmospheric absorption of laser by Lambert’s absorption law. As the important atmospheric scattering phenomenon generated by laser transferring is neglected, the diminishing coefficient is regarded as nearly equal to absorption coefficient. So the measured coarse absorption coefficient is 1.33129m-1 which means that the laser intensity decreases about 1.33129 times per meter exponentially. It is also showed from investigation that the absorption coefficient becomes larger, the atmospheric absorption increases evidently. Key words: Laser technique; Properties of air; Absorption coefficient; Rules of transferring 目录 TOC \o 1-3 \h \z \u HYPERLINK \l _Toc262110269 第1章 绪论 PAGEREF _Toc262110269 \h 1 HYPERLINK \l _Toc262110270 1.1 课题的研究背景及现实意义 P