全固态人眼安全拉曼激光器
发布时间：2018-10-14 08:59
【摘要】：1.5μm波段激光具有较高的人眼损伤阈值,而且处于“大气窗口”,在激光雷达,激光测距,大气遥感及空间光通信方面都有着重要应用。利用受激拉曼散射效应,可以将1.3μm转换为1.5μm。1.3μm在光纤通信、激光显示、医学等领域都有着广泛应用。Nd:YAP(掺钕铝酸钇)晶体4F3/2-4I13/2跃迁可输出波段在1.3μm附近,具有较大的跃迁截面和热导率,适合侧面泵浦。Nd:YAP晶体是自然双折射晶体,可输出为线偏振光,不会受到热退偏效应的影响。本论文的方案是采用准连续(QCW)激光二极管(laser diode,简称LD)侧面泵浦Nd:YAP晶体,BBO晶体电光主动调Q,结合ABCD激光传输矩阵,利用MATLAB软件数值模拟了平平腔和平凹腔的输出特性,选择合适的腔长和元件位置,产生1.34μm基频光。拉曼介质采用Ba(NO3)2(硝酸钡)晶体,利用外腔结构和单通拉曼发生器结构实现1.56μm人眼安全激光输出。本论文还对Nd:YAP晶体在1μm波段激光的输出特性进行了研究,在此基础上利用单通拉曼发生器结构激发Ba(NO3)2晶体产生了正三阶斯托克斯波长。主要研究内容概括如下:(1)采用b轴切割的Nd:YAP晶体作为激光晶体,BBO(偏硼酸钡)晶体电光主动调Q,分别利用平平腔和平凹腔实现1.34μm基频光高效输出。重频20Hz时,平平腔和平凹腔分别可获得单脉冲能量19.2mJ和18.3mJ,在平平腔时得到最窄脉宽38ns。实验还研究了Nd:YAP晶体中4F3/2-4I11/2跃迁产生的1080nm的输出特性,利用平平腔结构,重频20Hz时可得到1080nm单脉冲能量48.6mJ,脉宽27ns。(2)利用拉曼发生器结构,在基频光1.08μm和1.34μm分别获得正三阶斯托克斯波长(1218.50nm 1396.87nm和1637.25nm)和正一阶斯托克斯波长(1562.68nm)输出。在外腔拉曼激光器实验中,在基频光1.34μm单脉冲能量19.2m J时,获得一阶斯托克斯波长输出单脉冲能量1.83mJ,中心波长为1562.68nm,转换效率9.53%,脉宽被压缩到9ns。
[Abstract]:The 1.5 渭 m band laser has high threshold of human eye damage and is in the "atmospheric window". It has important applications in lidar, laser ranging, atmospheric remote sensing and space optical communication. Using stimulated Raman scattering, 1.3 渭 m can be converted to 1.5 渭 m.1.3 渭 m in optical fiber communication, laser display, medicine and other fields. The 4F3/2-4I13/2 transition band of Nd:YAP crystal can be near 1.3 渭 m. The Nd:YAP crystal is a natural birefringent crystal, which can output linearly polarized light without the effect of thermal depolarization. The scheme of this thesis is to use quasi continuous (QCW) laser diode (laser diode, (LD) side-pumped Nd:YAP crystal, BBO crystal electro-optic active Q-switched, combined with ABCD laser transmission matrix, using MATLAB software to simulate the output characteristics of flat cavity and concave cavity. A 1.34 渭 m fundamental frequency light is generated by selecting the appropriate cavity length and the position of the element. The Ba (NO3) 2 (barium nitrate) crystal is used in the Raman medium, and the external cavity structure and the single pass Raman generator structure are used to realize the 1.56 渭 m human eye safe laser output. The output characteristics of Nd:YAP crystal at 1 渭 m wavelength are also studied in this paper. On the basis of this, the structure of single pass Raman generator is used to excite Ba (NO3) 2 crystal to produce positive third order Stokes wavelength. The main research contents are summarized as follows: (1) the Nd:YAP crystal cut by b axis is used as the laser crystal, BBO (barium metaborate) crystal, the electrooptic QQ is actively switched, and 1.34 渭 m fundamental frequency light output is realized by using flat cavity and concave cavity respectively. The single pulse energy 19.2mJ and 18.3 MJ can be obtained in flat cavity and concave cavity respectively when 20Hz is repeated, and the narrowest pulse width is 38 ns in flat cavity. The output characteristics of 1080nm produced by 4F3/2-4I11/2 transition in Nd:YAP crystal are also studied. Using flat cavity structure, 1080nm monopulse energy 48.6 mJ and pulse width 27ns2 can be obtained when 20Hz is repeated. (2) Raman generator structure is used. The output of positive third order Stokes wavelength (1218.50nm 1396.87nm and 1637.25nm) and positive first order Stokes wavelength (1562.68nm) are obtained at 1.08 渭 m and 1.34 渭 m of fundamental frequency light, respectively. In the experiment of external cavity Raman laser, when the fundamental frequency light is 1.34 渭 m single pulse energy is 19.2m J, the first order Stokes wavelength output single pulse energy is 1.83 MJ, the center wavelength is 1562.68 nm, the conversion efficiency is 9.53 and the pulse width is compressed to 9ns.
【学位授予单位】：北京工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN248
本文编号：2269995
[Abstract]:The 1.5 渭 m band laser has high threshold of human eye damage and is in the "atmospheric window". It has important applications in lidar, laser ranging, atmospheric remote sensing and space optical communication. Using stimulated Raman scattering, 1.3 渭 m can be converted to 1.5 渭 m.1.3 渭 m in optical fiber communication, laser display, medicine and other fields. The 4F3/2-4I13/2 transition band of Nd:YAP crystal can be near 1.3 渭 m. The Nd:YAP crystal is a natural birefringent crystal, which can output linearly polarized light without the effect of thermal depolarization. The scheme of this thesis is to use quasi continuous (QCW) laser diode (laser diode, (LD) side-pumped Nd:YAP crystal, BBO crystal electro-optic active Q-switched, combined with ABCD laser transmission matrix, using MATLAB software to simulate the output characteristics of flat cavity and concave cavity. A 1.34 渭 m fundamental frequency light is generated by selecting the appropriate cavity length and the position of the element. The Ba (NO3) 2 (barium nitrate) crystal is used in the Raman medium, and the external cavity structure and the single pass Raman generator structure are used to realize the 1.56 渭 m human eye safe laser output. The output characteristics of Nd:YAP crystal at 1 渭 m wavelength are also studied in this paper. On the basis of this, the structure of single pass Raman generator is used to excite Ba (NO3) 2 crystal to produce positive third order Stokes wavelength. The main research contents are summarized as follows: (1) the Nd:YAP crystal cut by b axis is used as the laser crystal, BBO (barium metaborate) crystal, the electrooptic QQ is actively switched, and 1.34 渭 m fundamental frequency light output is realized by using flat cavity and concave cavity respectively. The single pulse energy 19.2mJ and 18.3 MJ can be obtained in flat cavity and concave cavity respectively when 20Hz is repeated, and the narrowest pulse width is 38 ns in flat cavity. The output characteristics of 1080nm produced by 4F3/2-4I11/2 transition in Nd:YAP crystal are also studied. Using flat cavity structure, 1080nm monopulse energy 48.6 mJ and pulse width 27ns2 can be obtained when 20Hz is repeated. (2) Raman generator structure is used. The output of positive third order Stokes wavelength (1218.50nm 1396.87nm and 1637.25nm) and positive first order Stokes wavelength (1562.68nm) are obtained at 1.08 渭 m and 1.34 渭 m of fundamental frequency light, respectively. In the experiment of external cavity Raman laser, when the fundamental frequency light is 1.34 渭 m single pulse energy is 19.2m J, the first order Stokes wavelength output single pulse energy is 1.83 MJ, the center wavelength is 1562.68 nm, the conversion efficiency is 9.53 and the pulse width is compressed to 9ns.
【学位授予单位】：北京工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN248
【参考文献】
相关期刊论文 前1条
1 朱海永;张戈;黄呈辉;魏勇;黄凌雄;陈静;陈玮冬;位民;陈振强;;高功率连续侧面泵浦1341.4 nm Nd:YAP激光器[J];强激光与粒子束;2006年09期
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