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分析了色散棱镜的特性及其顶角设计问题。讨论了色散棱镜和扩束棱镜在布鲁斯特角入射状态下,可组合使用的形式及单程角色散。提出将色散棱镜与扩束棱镜组合使用,可减少色散棱镜个数而获得更大角色散的方法。并据此设计了两个色散棱镜组,在Ti∶S激光器中得到实际使用。 相似文献
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本文推导了双扩束棱镜系统的角色散公式,从理论上证明了一个不带标准具的、由双棱镜扩束系统组成的调谐腔,能够达到GHz量级(~10~(-2)(?))的窄带可调谐激光,且经实验验证获得了小于4GHz的激光输出,为采用多棱镜系统以获得小于1GHz的窄带激光提供了理论依据.此外,还分析了这种系统具有反射损耗小、偏振运转和调整容易等优点,表明双(多)棱镜扩束系统是一种比较理想的光扩束、滤波、调谐多功能的光学元件. 相似文献
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本文指出,利用扩束棱镜将高斯光斑在一维方向扩束,能明显地提高多个探测器所探测的激光陀螺拍频信号的信噪比. 相似文献
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《物理学报》2021,(15)
角锥棱镜是激光反射器的主要光学组件,在合作目标卫星激光测距中发挥着关键作用.精确计算角锥棱镜的远场衍射图样是估算激光测距回波能量的必要过程.本文基于角锥棱镜的反射原理,分析了不同激光入射方向对反射器有效反射面积的影响,提出了一种适用范围更广的有效反射面积计算方法,同时分析了激光入射方向对角锥棱镜光学反射率的影响.在此基础上,应用光学标量衍射理论建立了远场衍射图样算法,分别对多种激光入射方向的镀金属(银)膜和无镀膜角锥棱镜进行了远场衍射图样仿真计算,得到了两类角锥棱镜的远场衍射图样分布随入射方向变化的规律.搭建了角锥棱镜远场衍射图样测试系统,通过实测结果与仿真计算的对比分析,验证了仿真计算的准确性. 相似文献
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<正> 本文用数学方法论证棱镜转动定理,并用解析法求解反射棱镜的特征方向、极值轴向和象偏转极值。一、反射棱镜的作用矩阵透镜本身是一个旋转体,其光轴为旋转轴,物、象关系是轴对称的,分析计算时在一个平面内研究物点和象点关系就可以了。反射棱镜则由于反射面的作用,光轴变成折线,光轴有 相似文献
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为了对大口径平面镜面形轮廓的五棱镜扫描法测试进行误差分析和修正,对五棱镜转动时出射光角度的变化进行了分析与精确计算。首先建立了合适的坐标系并规定了角度的正负,然后由入射光的偏摆角和俯仰角计算入射光向量,接着介绍了五棱镜的作用矩阵与坐标转换矩阵,在此基础上详细分析了五棱镜转动的整个过程并且计算了出射光向量。然后计算出射光的偏摆角和俯仰角,再计算当五棱镜没有转动时出射光的偏摆角和俯仰角。最后计算出射光偏摆角和俯仰角的变化。特别分析了当入射光垂直入射五棱镜的情况。随后进行了实际计算与实验,总结了出射光角度变化的一些规律。将计算数据与实验数据进行了比较,结果最大偏差为1"。最大偏差在实验精度范围内,证明了计算方法是正确的。 相似文献
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杨松许韬刘在洲席文强 《光学与光电技术》2023,(3):100-104
波罗棱镜谐振腔激光器具有机械稳定度高、光束质量好的特点。波罗棱镜会使入射光退偏,调Q时1/4λ波片无法有效工作,需要使用适当的波片补偿。利用琼斯矩阵建立波罗棱镜谐振腔调Q的数学模型并进行求解计算。分析了不同波罗棱镜方位角下的最优补偿波片并计算了波片公差、波罗棱镜折射率公差、方位角安装公差等对消光比的影响。当波罗棱镜水平放置,波片相位公差±0.02λ,关门消光比大于20 dB;波罗棱镜45°/135°放置时,存在四种对应的最优关门波片,波罗棱镜方位角0±4.66°的范围内,关门消光比可大于30 d B。以上结果为波罗棱镜谐振腔调Q激光器的设计提供更优及更具工程化意义的依据。 相似文献
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Calculations of the effects of amplified spontaneous emission (ASE) in laser amplifiers designed to amplify sub-picosecond pulses are presented. A one-dimensional code is used with some simple approximations to account for aspect ratio variation in cases of cylindrical symmetry. Gain depletion due to ASE is compared for various multi-pass geometries. Optimisation for short pulse amplification of a telescopic, beam-expanding, 4-pass amplifier is considered.On leave from Electrotechnical Laboratory, Tsukuba, Ibaraki, Japan 相似文献
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Numerical Investigation of Surface Plasmons Associated Subwavelength Optical Single-Pass Effect
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Surface plasmons (SPs) associated optical single-pass effect has been investigated in novel subwavelength metallic structures, including single slit and grating structures. With influence of SPs, these metallic structures can enhance transmission in incident direction and suppress it in the opposite direction, exhibiting a single-pass effect. The finite difference time domain method is employed to study the influences of structure parameters on far-field transmission, near-field electric field distribution and extinction ratio of the single-pass transmission effect. A maximal extinction ratio of 47.83dB is achieved in the grating structure. 相似文献
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The use of a low finesse enhancement cavity resonant with a low average power (<1 W) and a high repetition rate (78 MHz) pump source is shown to achieve 55% conversion efficiency into signal and idler from the coupled pump in an optical parametric process, whereas an equivalent amount of pump power in a single-pass configuration leads to negligible conversion. Careful comparison of the intracavity conversion process to the single-pass case is performed to assess the underlying impedance matching that yields the high conversion results. 相似文献
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CAO Sansong 《Chinese Journal of Lasers》2002,11(6):409-412
The output of Nd∶YAG single-pass laser amplifiers is studied analytically and experimentally. Methods of analysis for single-pass Nd∶YAG laser amplifier are presented. A flashlamp-pumped Q-switched Nd∶YAG oscillator/amplifier laser system has been developed with the average output power of 121.5 W. 相似文献
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The output of Nd∶YAG single-pass laser amplifiers is studied analytically and experimentally. Methods of analysis for single-pass Nd∶YAG laser amplifier are presented. A flashlamp-pumped Q-switched Nd∶YAG oscillator/amplifier laser system has been developed with the average output power of 121.5 W. 相似文献
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V. V. D’yachenko M. A. Irzak E. N. Tregubova O. N. Shcherbinin 《Technical Physics》2003,48(8):1061-1066
Feasibility of rf plasma heating in the Globus-M spherical tokamak at frequencies several times higher than the ion cyclotron
frequency is considered. Results from a numerical analysis of this problem by using one-and two-dimensional codes are presented.
It is shown that, for the plasma parameters attainable in this device, the single-pass absorption of fast magnetosonic waves
reaches 60%. The energy is released near the plasma axis. The radiation resistance of a one-loop antenna should be close to
1 Ω. The design of an antenna that allows one to match the rf oscillator to the load is described. The parameters of the antenna
resonator required for optimum operation of the antenna are given. 相似文献
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All optical techniques used to probe the properties of Bose-Einstein condensates have been based on dispersion and absorption that can be described by a two-level atom. Both phenomena lead to spontaneous emission that is destructive at the low energies involved with ultracold atomic systems. Recently, both were shown to lead to the same limit to the signal to noise ratio for a given destruction. We develop a new method for calculating the phase shift of a laser beam and show that no single-pass optical technique using classical light and a three-level atom can exceed this limit. This puts significant restrictions on potential nondestructive measurement schemes. 相似文献
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In this paper, effects of process variables on wall thickness, powder primary efficiency and speed of forming a thin metallic wall in single-pass coaxial laser cladding are investigated, and some resolution models are established and testified experimentally. With some assumptions, each of wall thickness, powder primary efficiency and formation speed can be defined as a function of the process variables. Wall thickness is equal to width of the molten pool created in single-pass laser cladding and determined by laser absorptivity, laser power, initial temperature, scanning speed and thermo-physical properties of clad material. Powder primary efficiency and formation speed are both dependent on an exponential function involving the ratio of melt pool width, which is decided by the process variables, to powder flow diameter. In addition, formation speed is influenced by powder feed rate. In present experiment, a 500 W continual-wave (CW) CO2 laser is used to produce thin-wall samples by single-pass coaxial laser cladding. The experimental results agree well with the calculation values despite some errors. 相似文献