一种控制环形激光器光学腔长的新方法

提出了一种控制环形激光器光学腔长的新方法.该方法是利用压电陶瓷电控环形激光器毛细管内干燥空气的折射率,实现对环形激光器光学腔长的控制.这种控制方法对环形激光器性能影响很小,具有响应速度快、灵敏度高、功耗低等优点,可用于全反射棱镜式环形激光器、反射镜式环形激光器的稳频系统.对于激光陀螺、激光计量等应用具有重要意义.     

几种新型全反射棱镜式环形激光器的模式选择技术

根据全反射棱镜式环形激光器(TRPRL)的矩阵光学理论和环形He-Ne激光器内环形激光的工作理论,研究了TRPRL的激光模式选择技术方法,可令环形激光器内的顺时针和逆时针两个方向上的激光工作在单谱线、单横模、单纵模的状态,从而在环形激光器内形成稳定的驻波,输出到光电探测器上稳定的干涉条纹信号波形。采用缩短TRPRL的毛细管直径方法,可抑制3.39μm谱线;由于TRPRL的特殊的环形激光器结构,采用分立式特殊结构设计的选频光阑,选频光阑可以放到环形激光器的光路任意位置处,而多个选频光阑即可有效抑制1.15μm的谱线;根据不同波长激光腰斑半径的不同,在光腰处采用特制的椭圆小孔光阑,抑制0.63μm激光的高阶横模。对于TRPRL在全反射棱镜式激光陀螺(TRPLG)中的应用具有重要意义。     

全反射棱镜式环形激光器的温度效应

根据矩阵光学理论,研究了全反射棱镜式环形激光器（TRPRL）光路的温度效应.从理论上给出了描述光路中光学元件在介质折射率变化时的3×3变换矩阵,建立了折射率变化时谐振腔内光路的偏转模型,由此讨论了温度变化导致TRPRL光路的偏转规律,并研究了降低TRPRL温度效应对其性能影响的方法.所得结论对TRPRL的设计和运用有重要指导意义.     

全反射棱镜式激光陀螺自适应稳频技术EI北大核心CSCD

针对全反射棱镜式激光陀螺在稳频过程中相敏信号易受噪声干扰的现象,研究了全反射棱镜式激光陀螺自适应稳频技术。理论分析了全反射棱镜式激光陀螺的稳频特性,结合自适应噪声对消原理,建立了全反射棱镜式激光陀螺自适应稳频系统的数学模型。通过硬件电路设计,搭建了基于递归最小二乘算法的自适应稳频控制系统。分别对原有稳频技术与自适应稳频技术进行了实验测试,实验结果表明,自适应稳频能有效消除噪声对相敏信号的干扰,稳频精度提高了近一个数量级,陀螺精度相应提高了60%以上。此分析结果为提高全反射棱镜式激光陀螺的性能提供了重要参考。     

全反射棱镜式激光陀螺自适应稳频技术

针对全反射棱镜式激光陀螺在稳频过程中相敏信号易受噪声干扰的现象,研究了全反射棱镜式激光陀螺自适应稳频技术。理论分析了全反射棱镜式激光陀螺的稳频特性,结合自适应噪声对消原理,建立了全反射棱镜式激光陀螺自适应稳频系统的数学模型。通过硬件电路设计,搭建了基于递归最小二乘算法的自适应稳频控制系统。分别对原有稳频技术与自适应稳频技术进行了实验测试,实验结果表明,自适应稳频能有效消除噪声对相敏信号的干扰,稳频精度提高了近一个数量级,陀螺精度相应提高了60%以上。此分析结果为提高全反射棱镜式激光陀螺的性能提供了重要参考。     

全反射棱镜式激光陀螺标度因数补偿技术

针对全反射棱镜式激光陀螺标度因数随温度周期性变化的现象,根据矩阵光学方法研究了稳频状态下温度变化对环形激光面积的影响,获得了全反射棱镜式激光陀螺标度因数与稳频电压的关系,并得出光束偏移是引起标度因数随温度周期性变化的原因。根据标度因数与稳频电压的关系,建立了全反射棱镜式激光陀螺标度因数补偿模型,通过实验对比了补偿前后标度因数的非线性度。结果表明,根据该补偿模型对全反射棱镜式激光陀螺标度因数进行补偿,标度因数非线性度提高了一个数量级以上,对提高全反射棱镜式激光陀螺的性能具有一定的参考价值。     

温度扰动对棱镜式激光陀螺特性的影响

考虑温度扰动的情况下,对光在棱镜表面反射和折射的传输矩阵进行了修正.根据激光环形腔自洽理论,建立了温度扰动下的棱镜式激光陀螺腔内光束传输物理模型,分析了温度扰动对陀螺频率偏移、标度因数等参数的影响.理论分析表明,当温度在-40~70℃范围波动时,激光陀螺光学腔长变化量、频率偏移量和标度因数变化量依次为10.04μm、0.011 MHz和1.96×10~(-10).建立了棱镜式激光陀螺变温实验系统,实验结果与理论分析相吻合.     

基于角锥棱镜的非平面单频环形腔本征态分析

对基于角锥棱镜的非平面单频环行激光器的本征态问题进行了详细讨论,通过参考光线研究了该环形腔的光路闭合情况.腔内允许存在的四个本征椭圆偏振态,由于模式竞争,最终仅存一个本征模式振荡,从而实现单频运转.通过对腔内环路矩阵结构的分析,得出该环形腔中线偏振模式的产生需要系统的光路结构对称.对角锥棱镜的圆柱部分施加磁场,随着磁场的增大,对称光路结构中的本征态结构发生变化,并在适当磁场处出现线偏振模式.     

角锥型全固态非平面环形激光器473 nm单频运转

提出并实现了由热键合直角棱镜与角锥棱镜构成的新型946 nm及473 nm单频非平面环形激光器.直角棱镜由无掺杂的YAG晶体和2 mm厚的Nd∶YAG晶体热键合形成,可提供激光增益、光路闭合及对946 nm激光起偏等多种复合功能.角锥棱镜由熔融石英材料构成,在环形永磁铁作用下,提供法拉第旋转作用.实验上实现了该结构的946 nm腔内倍频,并获得了473 nm单频单向激光输出.     

角锥型全固态非平面环形激光器473 nm单频运转

提出并实现了由热键合直角棱镜与角锥棱镜构成的新型946 nm及473 nm单频非平面环形激光器.直角棱镜由无掺杂的YAG晶体和2 mm厚的Nd∶YAG晶体热键合形成,可提供激光增益、光路闭合及对946 nm激光起偏等多种复合功能.角锥棱镜由熔融石英材料构成,在环形永磁铁作用下,提供法拉第旋转作用.实验上实现了该结构的946 nm腔内倍频,并获得了473 nm单频单向激光输出.     

A mirror-free cavity configuration for a CW ring dye laser

A new cavity configuration without mirrors is described for a CW ring dye laser. The cavity design is based on a new type of focusing prism which uses the Brewster angle of incidence and total internal reflection. Special roof prisms allow wavelength tuning. All of these elements are made from uncoated quartz thus allowing dye laser operation over a large range of wavelengths. CW operation as well as synchronously pumped mode locked operation with intracavity doubling is reported using the Rhodamine 6G dye.     

Art output mirror for fir laser

ATR prism was used firstly as the FIR laser output coupler. Such output mirror possesses good separation of the pump (λ≈10μm) and FIR radiation without losses. Transmittance of this mirror can be simply controlled by adjustment of gap between two output prisms. The dependence of mirror output characteristics on pump radiation polarization, prism refractive index, gap between prisms are under consideration.     

光波导技术同步测量棱镜及波导薄膜参数

依据全反射理论和棱镜耦合原理,实现了对棱镜折射率及波导薄膜材料折射率和厚度的同步测量。使用高准直半导体激光器激光入射到棱镜内部与波导膜的分界面上,逐步旋转棱镜或改变棱镜的入射角,得到棱镜耦合M线,曲线前面几组的波谷为波导模激发,在M线左侧收尾处有一个不完整波峰,其反射光强随入射角迅速衰减,为全反射时的临界点,由此可实现棱镜及波导薄膜参数的同步测量;用此法测量了棱镜耦合一体化平面波导棱镜的折射率和聚甲基丙烯酸甲酯(PMMA)聚合物波导薄膜的折射率和厚度。测量棱镜折射率精度为±1.9×10-4,波导薄膜折射率和厚度的精度分别为±6.2×10-4 μm和±1.6×10-2 μm。     

A prism anamorphic system for Gaussian beam expander

Basic properties are given of the prism anamorphic expander of a Gaussian beam composed of a couple of prisms in tandem. Its shorter overall length for a given expansion, relative ease of optical adjustment, a sharp selection of polarization component, and rather small inclusive dispersion make it an excellent beam expander in a specific laser cavity. The design principle is presented of the prism system with a grating for an anastigmatic optical resonator for a dye laser of narrow linewidth and of short pulse duration.     

考虑晶体应力情况下的单块非平面环形腔分析

简要分析了单块非平面环形腔单频激光器的基本原理,并采用琼斯矩阵计算了单块单向行波非平面环形腔内的本征偏振态。深入分析了磁场强度、输出面偏振反射系数、入射角、非平面角及腔内其它参量对各本征偏振态的损耗及两本征偏振态间损耗差的影响,并且指出如何选择各参量以降低本征偏振态的损耗且增大两本征偏振态间的损耗差。最后还通过计算晶体应力在两个本征偏振态方向引起的相位差,讨论了应力作用方向以及应力双折射系数对腔内本征偏振态的损耗和两本征偏振态间损耗差的影响。     

The Optimum Coupling Coefficient of Optically Pumped NH3 Far-Infrared Cavity Laser

Based on the semiclassical density matrix theory, the optimum output power reflection coefficient (coupling coefficient) of output coupler for optically pumped NH₃ far-infrared (FIR) cavity laser was calculated by means of iteration method. Experimentally, FIR Fabry-Perot cavity laser was designed and constructed by using inductive metallic meshes as couplers, and the measurement showed that the theoretical calculation were in agreement with experimental results.     

可调谐激光器腔内色散棱镜及其组合

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。     

Direct intensity modulation of a rectangular ring laser with bidirectional lasing characteristics

The direct intensity modulation of a three-guide coupled rectangular ring laser having bidirectional lasing characteristics is reported for the first time. The rectangular laser cavity consists of four low loss total internal reflection mirrors and an output coupler made out of three passive coupled waveguides. The laser is fabricated using a total cavity length of 580 μm with active section lengths of 250 μm. For both the clockwise and counterclockwise circulating directions, a lasing threshold of around 38 mA is obtained at room temperature under continuous wave operation. A maximum 3-dB modulation bandwidth of approximately 3.2 GHz is observed in both circulating directions.     

Generation of a radially polarized laser beam by use of a conical Brewster prism

To generate a radially polarized laser beam we designed and fabricated a new Brewster optical element that consists of convex and concave conical prisms. The lateral surface of the convex conical prism was coated with a dielectric multilayer (SiO2 and Ta2O5) to enhance polarization selectivity. By combining two prisms we obtained a conical Brewster prism without beam divergence owing to refraction. A radially polarized TEM01* (R-TEM01*) mode laser beam was demonstrated when this prism was used inside a Nd:YAG laser cavity.