双侧横向抽运的染料激光放大器的实验研究

染料激光器以其激光光谱覆盖范围广、激光波长连续可调节、可以实现窄激光脉宽和窄激光线宽运转等特点在激光光谱学、激光受控化学反应、激光大气传播等许多领域得到了广泛的应用.为了获得高输出功率的染料激光,通常将染料激光振荡器输出的激光注入到染料激光放大器进行功率放大.本文对我们自己研制的双侧横向抽运方式的染料激光放大器进行了实验研究. 实验获得了染料激光输出功率34 W,抽运激光功率提取效率37%的结果.文中对实验结果进行了必要的分析,讨论了染料溶液浓度、染料激光波长、注入染料激光功率及抽运激光功率对染料激光放大器输出激光功率以及抽运激光功率提取效率的影响,给出了相应的实验结果曲线.(OC36)     

空阴极氦-氪离子激光器的实验研究

通过改革HCD He-Kr离子激光器的结构和电源,激光输出特性获得了很好的改善。通过观察各种自发辐射谱线输出波形,分析研究了激光输出波形的形成机理。实验结果指出,阴极溅射是影响He-Kr HCD离子激光器激光输出波形和输出功率的主要原因之一。     

染料液晶同激光的非线性光学效应研究

本文研究了激光同染料液晶的非线性光学效应。理论分析了激光在染料液晶中的传输过程,分别计算了当入射激光功率为10mW/cm2和50mW/cm2时的输出激光光强分布。实验测量了532nm连续激光通过染料液晶传输后的光限幅曲线,观察了输出激光光斑形状随入射激光光强的变化,实验结果与计算结果基本相吻合。     

CO2激光辐照下热敏电阻温升的数值计算与实验

对激光照射下热敏电阻的温升进行计算,得到温升和热敏电阻输出信号与入射激光功率的关系：当激光功率小于热敏电阻的破坏阈值时,输出信号与激光功率近似线性关系;同时计算了破坏阈值的大小。实验采用CO2激光器,测量了热敏电阻输出信号与入射激光功率的曲线,分析表明,热敏电阻吸收激光能量造成的热破坏是主要原因,在允许的误差范围内,计算与实验结果基本一致。     

高功率准分子激光参数测量研究

介绍了对高功率XeCl准分子激光MOPA系统中前三台激光器的输出激光进行的参数测量.实验分别对MOPA系统的前端输出种子光及其经过一级、二级、三级放大后所得激光进行了测量,研究包括采用哈特曼波前传感器对激光近场波前的测量和采用激光光束分析仪对激光远场光强的测量两个方面,分别得出激光的近场相位均方根误差和不同光斑尺寸定义下的远场发散角等实验测量结果,将实验结果与系统设计值进行比较分析,从而对激光器系统输出激光作出评价.     

光纤技术用1.318μm和1.338μmNd~(3+):YAG固体激光器

根据光纤技术对1.3μmNd~(3+):YAG激光输出的要求,我们研制了1.3μmNd~(3+):YAG固体激光器,在全腔水冷聚光腔和泵浦灯、激光棒分别水冷的聚光腔中,分别获得了阈值750W、连续输出功率900mW和阈值1000W、连续输出功率6W的激光输出。本文报道了该激光器的实验研究和激光输出参量测量结果,同时讨论了获得1.318μm和1.338μm激光输出的途径和方法。     

CO2激光辐照下热敏电阻温升的数值计算与实验

对激光照射下热敏电阻的温升进行计算,得到温升和热敏电阻输出信号与入射激光功率的关系当激光功率小于热敏电阻的破坏阈值时,输出信号与激光功率近似线性关系;同时计算了破坏阈值的大小.实验采用CO2激光器,测量了热敏电阻输出信号与入射激光功率的曲线,分析表明,热敏电阻吸收激光能量造成的热破坏是主要原因,在允许的误差范围内,计算与实验结果基本一致.     

Yb∶YAG陶瓷强化Cr,Yb∶YAG自调Q微片激光器性能研究

报道了通过键合Yb∶YAG激光陶瓷来强化Cr,Yb∶YAG自调Q微片激光器激光性能的研究结果。实现了Yb∶YAG/Cr,Yb∶YAG自调Q微片激光器的激光输出。当吸收抽运功率为7.1W时获得了0.53W的自调Q激光输出,对应的光-光转换效率为7.5%。在实验中获得了脉冲能量大于25μJ、脉冲宽度小于3ns、峰值功率高达9kW的自调Q激光脉冲输出。同时研究了输出耦合镜透射率对Yb∶YAG/Cr,Yb∶YAG自调Q微片激光器激光性能的影响。     

脏外染料被动压缩准分子激光的输出脉冲特性研究

用紫外染料PTP、BPBD、t-B_uPBD等对XeC1准分子激光施行腔外被动压缩,获得了压缩比为3的XeC1激光脉冲透射输出和压缩比大于8的染料辐射输出。提出“光子传输速率方程”来描述被动压缩现象,计算机模拟计算结果较好地解释了准分子激光压缩及染料辐射的实验结果。     

LD端面抽运Nd:YAP 1341.4nm激光器

为了研究Nd:YAP晶体在LD端面抽运中的1341.4nm激光输出特性,采用理论计算和实验测量了实验系统的热焦距,对比了平平腔和平凹腔激光输出结果。采用输出耦合率为T=2.4%的平凹腔和输出耦合率为T=2.6%的平平腔,分别得到了3.15W和2.86W的1341.4nm线偏振激光输出,对应斜效率分别为18.4%和17.5%。结果表明,Nd:YAP作为1.3μm波段激光晶体具有潜在的优点。     

脉冲激光泵浦的钛宝石激光器

本文主要从理论和实验上研究了脉冲钛宝石激光器的输出特性     

Far-infrared raman laser with high intensity laser pumping

Theoretical and experimental results are presented for a pulsed far-infrared (FIR) molecular gas laser with high intensity laser pumping. In these FIR lasers, high intensity pumping is found to produce stimulated Raman emission at very large offsets (up to 30 GHz) from resonance with the intermediate state. A theoretical, density matrix model is developed for these lasers to account for simultaneous Raman emission on rotational levels in the ground and excited vibrational states (double Raman resonance). This theoretical approach is necessary in the case of off-resonant, high intensity pumping. Theory predicts the FIR emission frequency, the FIR laser gain, and the pump threshold intensity as a function of pump laser frequency. Experimental results are obtained onP-,Q-, andR-branch transitions in¹²CH3F and¹³CH3F using a single-mode, grating tuned CO2TEA pump laser with an intensity of up to 40 MW/cm². Good agreement is obtained between theory and experiment for the observed values of FIR emission frequency and pump threshold intensity. These results indicate that a widely tunable (150-1200 mum), pulsed FIR CH3F laser could be constructed with a tunable, multiatmospheric CO2pump laser of modest power (about 2-5 MW).     

飞秒激光在材料微加工中的应用

本文介绍了飞秒激光的特性以及超短脉冲激光与材料相互作用的机理，并着重指出了其与长脉冲激光的区别。飞秒激光可产生超高光强、具有精确的损伤阈值(并且损伤阈值较低较低)、很小的热影响区、几乎可精密加工所有种类材料，并且，加工精度极高，可进行亚微米尺寸的精密加工。通过分析飞秒激光材料微加工的特性，综述超短脉冲激光材料微加工的应用研究现状。     

激光参数对激光激发超声信号的影响分析

研究了激光参数对激光激发超声信号的影响.研究中首先理论分析激光激发超声过程中,激光参数对激发超声信号的影响.同时,设计并搭建一种激光激发超声的实验装置,实验验证理论分析结果.该实验装置应用脉冲激光配合光衰减结构对被测目标激发产生超声波,通过超声探头实现激光超声信号的探测.实验中以铝板为检测对象,对激光脉冲能量和照射光斑大小对激发超声信号的影响进行实验分析.通过理论分析及实验验证,可得出照射光斑直径与激光能量会直接影响入射激光功率密度,从而影响激发超声的幅度.     

扭动光束钕玻璃棒状激光放大器

利用扭动入射激光束抑制在钕玻璃内部产生的热自聚焦效应。在5～10毫秒脉宽范围内,钕玻璃的破坏阈值提高了一倍以上,同时大幅度地提高了光束亮度。建立了两种扭动光束的复元机构。     

The self-pulsing laser oscillator

The self-pulsing laser oscillator is examined theoretically by developing a simple model based on the assumption that the pulse in the laser cavity is a 180° pulse for the medium. The concept of an optical 180° pulse is closely analogous to the idea of a 180° RF pulse discussed in spin-echo studies. The range of parameters for which a laser oscillator is expected to be self-pulsing is found from this theory, and the results are compared with experimental observations of the behavior of a 6328 Å He-Ne laser oscillator. Observations of self-pulsing are made as a function of cavity length, position of the gain medium in the laser cavity, and laser excitation. Observations of pulse widths and output frequency spectra are also reported. It is found that the main features of the experimental observations agree well with the theoretical predictions.     

The reliability of laser diodes and laser transmitter modules

This paper reviews the reliability of laser transmitter modules for use in optical fibre transmission systems. Methods for reliability testing and lifetime prediction are discussed and the dominant failure mechanisms affecting laser modules are described. The current status of laser module reliability is discussed, based on both published results, and on the findings of a study at BT Laboratories of the reliability of commercial laser modules from ten manufacturers. It is concluded that significant progress has been made in the reliability of laser diodes, through the understanding of basic failure mechanisms, leading to long predicted lifetimes for a number of different laser structures. However, module packaging is less reliable and further work is required to identify and eliminate those materials and processing technologies which lead to the risk of early failure.     

HY-2卫星激光反射器理论分析及激光测距实验

激光反射器作为一种被动无源光学合作目标,是人造卫星激光测距系统中的重要组成部分。对于运行在低轨卫星中的激光反射器,既要在较大的激光入射角范围提供服务,又要将角反射器阵列结构所引入的综合测距误差控制在一定范围内,以保证高精度的激光测距,因此绝大多数采用半球形阵列结构。文中以我国海洋二号卫星激光反射器为例,对半球形激光反射器的远场衍射分布、相对有效反射面积分布、距离更正误差分布和激光测距综合精度等核心技术参数进行理论分析。并以国内流动式卫星激光测距系统TROS1000对海洋二号卫星激光反射器进行追踪和激光测距实验,测量结果表明,激光测距内符合精度为1.1 cm,理论分析与实测结果相符。标志着海洋二号卫星激光反射器性能优良,这对以后激光卫星反射器的设计具有指导意义。     

XeCl激光泵浦的ns染料激光器

报道了以XeCl准分子激光作泵浦源,通过所谓的“控制腔瞬态过程”的方法,直接获得ns染料激光脉冲的实验结果。与N_2光泵浦比较,XeCl激光泵浦可得到更短波长和更高阈值系统的激光振荡。     

带空间滤波器的激光聚焦系统对多模激光的聚焦

本文简单介绍了使用带空间滤波器的激光聚焦系统对多模激光进行聚焦的结果。