毕业设计说明书
基于980nm半导体激光器 光束准直系统的设计
学生姓名: 学号: 学 院: 专 业: 指导教师:
2012年 6 月
清华大学2012届毕业设计说明书
基于980nm半导体激光器光束准直系统的设计
摘要:半导体激光器具有体积小、重量轻、功耗低和可直接调制等优点,在激光雷达、激光通信、固体激光器的抽运、激光泵浦、激光扫描、激光测距、激光指挥笔等方面得到了非常广泛的应用。
由于半导体激光器的结构特点,使得它发出的光束在垂直于结平面方向上远场发散角和平行于结平面方向的远场发散角相差较大。所以在几乎所有要求较高的应用领域中,其输出光束都必须通过特殊的光学系统进行准直。
柱透镜因其结构简单、材料便宜以及加工容易而在半导体激光束准直领域获得较多的应用,但普通的柱透镜其准直能力非常有限,为了提高柱透镜的光束准直能力,就有必要设计出更加合理和可行的结构。
在本文中,基于柱透镜对半导体激光器光束准直的理论分析,设计了相互正交的柱透镜组作为设计模型,对980nm半导体激光器进行光束准直,并且利用ZEMAX软件对设计系统各部分准直效果进行模拟。
关键字:半导体激光器,光束准直,柱透镜,高斯光束
清华大学2012届毕业设计说明书
Based on the 980nm semiconductor laser beam
collimation system design
Abstract:Owing to its compactness,lightness,and low cost,semiconductor laser play an important role as coherent source in various fields of technology such as military,industry and medicine use and so on.
However,the output beam quality of semiconductor laser is poor.Because of the waveguide properties of their active areas,semiconductor lasers generate large divergence-angle beams with alliptically shaped intensity profile.And the beam of semiconductor laser has astigmatism.So,the output beam must be collimated by optical systems in most practical work.
Because of simple structure and easy fabricating,the cylindrical lenses have been used in many practical applications for beam collimating of semiconductor lasers.
In this paper, Based on the cylindrical lens for semiconductor laser beam collimation theory analysis, Design of orthogonal cylindrical lens group as a design model, The 980nm semiconductor laser beam collimation,and using the ZEMAX software to the design of each part of the system of collimating and shaping effects simulation.
Key words:Semiconductor Laser,Beam collimation, Cylindrical lens, Gaussian beam
清华大学2012届毕业设计说明书
目 录
1 绪论???????????????????????????????? 1 1.1 选题目的及意义?????????????????????????? 1 1.2 980nm半导体激光器的发展及其应用????????????????? 1 1.2.1 半导体激光器发展史??????????????????????? 1 1.2.2 980nm半导体激光器的研究状况??????????????????? 3 1.2.3 980nm半导体激光器的主要应用???????????????????4 1.3 准直技术的意义与研究??????????????????????? 5 1.3.1 半导体激光器光束准直的意义??????????????????? 5 1.3.2 准直技术的研究现状和发展方向?????????????????? 6 1.4 本论文主要工作???????????????????????????7 1.5 本章小结??????????????????????????????8 2 半导体激光器????????????????????????????9 2.1 半导体激光器的基本原理???????????????????????9 2.1.1 受激辐射?????????????????????????????9 2.1.2 实现条件?????????????????????????????9 2.2 半导体激光器的器件结构??????????????????????10 2.2.1 异质结半导体激光器???????????????????????10 2.2.2 量子阱半导体激光器???????????????????????11 2.2.3 表面发射激光器???????????????????????13 2.3 半导体激光器的优缺点???????????????????????13 2.4 本章小结?????????????????????????????14
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清华大学2012届毕业设计说明书
3 半导体激光器的光束准直理论?????????????????????15 3.1 半导体激光器的光束特性??????????????????????15 3.2 高斯光束的基本理论????????????????????????15 3.3 激光束准直系统介绍????????????????????????16 3.3.1 圆柱透镜系统??????????????????????????16 3.3.2 非球面柱透镜准直系统?????????????????????17 3.3.3 光纤耦合系统??????????????????????????18 3.3.4 棱镜组折反射光束整形??????????????????????20 3.3.5 异型棱镜光束整形????????????????????????21 3.4 本章小结?????????????????????????????22 4 半导体激光器准直系统设计??????????????????????23 4.1 准直系统设计方案?????????????????????????23 4.2 准直设计优化仿真?????????????????????????27 4.2.1 光学设计软件??????????????????????????27 4.2.2 ZEMAX软件仿真?????????????????????????27 4.3 本章小结????????????????????????????30 5 全文总结??????????????????????????????31 5.1 主要工作及结论??????????????????????????31 5.2 工作展望?????????????????????????????31 参考文献???????????????????????????????32 致谢 ???????????????????????????????? 34
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