电象的选择不唯一

通过实例证明了电象的选择不唯一,同时也指出了有关文献在论证电象选择唯一性时的不妥之处．     

Metal wave-guide to dielectric image guide transition using exponential taper

A unique metal wave guide to dielectric image guide transition has been developed using exponential taper in dielectric wave guide. The propagation characteristics have been computed theoretically and taper impedance for the different cross-sections have been evaluated, so as to match it with the metal wave guide for efficient mode conversion. Transmission loss and return loss for triangular and exponentail taper with frequency for same dimensional parameters have been measured.     

快反系统中平面反射镜的轻量化设计

根据快速控制反射镜系统(快反系统)对平面反射镜的设计要求,对快反镜的轻量化结构进行了优化设计。选择比刚度大、热变形系数小的碳化硅为镜坯材料,采用背部开槽式结构减重,背部3点式支撑,对不同筋宽和镜面厚度等多种轻量化方案进行了有限元分析。结果表明:筋宽越大,镜体刚度越好,但筋宽增大到一定程度时,反射镜刚度的改善程度减缓;镜面越厚,镜体内应力、自重变形越大。结合反射镜设计要求和有限元分析结果,加工制备了筋宽为4 mm,镜面厚度为4 mm的碳化硅反射镜,镜体轻量化率达55%。实测反射镜的面形精度,其RMS值不超过λ/30,与分析结果相符,满足系统的使用要求。     

碳化硅指向反射镜轴的高精度镶接技术研究

碳化硅具有优异的热学性能和机械性能,是高性能空间光学应用中的优选材料。但由于它的硬度很高,使得碳化硅反射镜的高精度加工和装配变得很困难。为了提高碳化硅反射镜与两个镜轴固接后的位置精度,采用了结合衬套修正的偏心轴补偿镶接方案。结果表明,这种方法可以将镶接完成后的两个镜轴的同轴度误差降低到0.005mm。由于在镶接过程中仅需要通用的加工设备和工装夹具,因此可以在保证良好经济性的前提下提高碳化硅反射镜的装配精度。     

四程放大系统腔镜位置变形镜的面形解

 根据在大型高功率固体激光装置中自适应光学技术的应用研究，将变形镜置于腔镜位置，有利于提高自适应光学系统的校正动态范围。基于变口径90°翻转四程放大系统的光路特点，从理论上比较完整地解决了四程放大系统腔镜位置变形镜面形解的存在性问题，并对口径变换比值(缩束比)与面形求解之间的关系问题进行了数值模拟，结果表明:只要缩束比小于1，对应系统连续波前畸变的腔镜位置面形解是存在的，且随着缩束比减小，解的收敛性增强。     

机械转镜隔离器

本文介绍一种新的,适用于高功率激光核聚变装置的隔离器.这种高速机械转镜隔离器(通光口径(?)140mm,转速6000rpm.)具有很高的隔离比和很低的插入损耗,还同时具有空间滤波和隔反向激光的功能.对发展这种隔离器需解决的同步问是,作了详细的讨论.测得同步精度优于0.3μs,复原精度优于1".对影响精度的因素作了分析.     

水冷式离焦变形镜技术研究

根据非稳腔薄片激光器腔内离焦的特点和主动校正的应用需求,针对性地设计离焦变形镜,对激光器腔内离焦进行实时补偿。采用压电陶瓷作为驱动器,圆形镜面圆心处设置1个驱动器,圆周上均布4个驱动器的5通道布局模式,仿真分析了筋板厚度和镜片厚度对离焦的校正效果影响,在优化设计的基础上研制出水冷式离焦变形镜,其静态面形PV值为0.34 m,波前动态范围为16 m。在离焦变形镜和二维变形镜组合模式下进行了薄片激光器强光主动光学校正试验,谐振腔腔内像差PV值从6.76减小到1.44,光束质量从19.5提高到6.5,有效地改善了输出光束质量,验证了离焦变形镜对非稳腔薄片激光器离焦校正的有效性和实用性。     

Grazing-incidence aplanatic mirror systems

In this paper the author adapts his own as well as other authors' results concerning aplanatic mirror systems to the condition of grazing-incidence, systematically taking account of extraparaxial constants.     

水冷式离焦变形镜技术研究

根据非稳腔薄片激光器腔内离焦的特点和主动校正的应用需求,针对性地设计离焦变形镜,对激光器腔内离焦进行实时补偿。采用压电陶瓷作为驱动器,圆形镜面圆心处设置1个驱动器,圆周上均布4个驱动器的5通道布局模式,仿真分析了筋板厚度和镜片厚度对离焦的校正效果影响,在优化设计的基础上研制出水冷式离焦变形镜,其静态面形PV值为0.34 m,波前动态范围为16 m。在离焦变形镜和二维变形镜组合模式下进行了薄片激光器强光主动光学校正试验,谐振腔腔内像差PV值从6.76减小到1.44,光束质量从19.5提高到6.5,有效地改善了输出光束质量,验证了离焦变形镜对非稳腔薄片激光器离焦校正的有效性和实用性。     

Characteristic investigation of Golay9 multiple mirror telescope with a spherical primary mirror

The sparse aperture provides a novel solution to the manufacturing difficulties of modern super large telescopes. Golay configurations are optimal in the sparse aperture family. Characteristics of the Golay9 multiple mirror telescope having a spherical primary mirror are investigated. The arrangement of the nine sub-mirrors is discussed after the planar Golay9 configuration is analyzed. The characteristics of the entrance pupil are derived by analyzing the sub-aperture shapes with different relative apertures and sub-mirror sizes. Formulas about the fill factor and the overlay factor are deduced. Their maximal values are presented based on the derived tangency condition. Formulas for the point spread function (PSF) and the modulation transfer function (MTF) of the Golay9 MMT are also deduced. Two Golay9 MMT have been developed by Zemax simulation. Their PSF, MTF, fill factors, and overlay factors prove that our theoretical results are consistent with the practical simulation ones.     

Wolter-I-like X ray telescope structure using one conical mirror and one quadric mirror

Nested multilayer mirrors are commonly used in X ray telescope structure to increase the collecting area. To balance the difficulty and cost of producing these mirrors, Wolter-I structures are replaced with conical Wolter-I structures, but these can lead to significantly poorer angular resolutions. In this Letter, we consider changing one of the mirror shapes(paraboloid or hyperboloid) of a Wolter-I structure to a conical mirror shape, while the other mirror shape remains a quadric surface-type structure, which can thus ensure the imaging quality. The cone-hyperboloid structure is nested to obtain on-axis angular resolution and off-axis images.     

大型天文望远镜主镜镀膜技术

采取主镜镜面向上真空蒸镀制备方式,开展了大型天文望远镜主镜铝加介质保护反射膜技术研究。结合ZZS3200型镀膜设备真空室几何配置,对传统膜厚分布计算物理模型进行了修正,分别分析了铝膜与介质膜层膜厚均匀性。结果表明:理论分析与实验数据一致,直径2.4 m范围内膜厚不均匀性约5.5%。通过优化工艺,成功制备出1.8 m平面镜薄膜元件,在350~1 800 nm波段范围内,膜层平均反射率88.6%,通过了环境稳定性测验。     

Graded reflectivity mirror unstablelaser resonators

The graded reflectivity mirror (GRM) unstable resonator has become the resonator of choice for many solid-state laser systems. This tutorial review discusses through a step-by-step approach the inner workings of such resonators, in order to identify for potential designers and users tradeoffs which are involved in their design. Geometrical and diffractive contributions to the mode definition are discussed using a canonical formulation applicable to all types of unstable resonators. Particular attention is given to super-Gaussian resonators, which are nowadays the most widely used. The beam-shaping action of an amplifying medium is illustrated through a practical example, which makes clear the necessity to use a proper simulation software to predict correctly the behaviour of the resonator. This revised version was published online in November 2006 with corrections to the Cover Date.     

Grand unification and mirror particles

The grand unification model containing standard and mirror particles is constructed. In models of this kind there exist such strings that a standard particle transforms into a mirror particle in going around the string.     

Alpha channeling in mirror machines

The injection of radio frequency waves can cool charged particles trapped in a magnetic mirror. This cooling effect relies upon waves with azimuthal and axial phase velocities resonating with ions in different axial locations. The ions are then forced to diffuse along highly constrained orbits, such that they can only exit the magnetic trap at low energy. This cooling effect may have application to magnetic fusion mirror machines, where the free energy of the fusion by-products, the alpha particles, might be channeled into the waves that effect the cooling, thereby both extracting the fusion ash quickly and making that energy available in a convenient form for more useful purposes.     

Multilayered “black mirror”

Journal of Applied Spectroscopy -     

Positronium versus the mirror universe

A mirror universe of fermions and forces isomorphic to but distinct from those we see couples directly to our universe only by gravity. Particles at any mass scale enjoying both normal and shadow forces forge an electromagnetic link (by radiative corrections) between the two universes such that mirror particles display conventional electric charges 10⁻³–10⁻⁵ e. This produces mixing between triplet positronium and its analogous mirror state through a one-photon annihilation diagram. Consequent effects are contrary to experiment. The possible existence of such a mirror universe is thereby excluded.     

Normal-incidence electrostatic Rydberg atom mirror

A Rydberg atom mirror has been designed and its operational principle tested experimentally. A supersonic expansion containing H atoms moving with a velocity of 720 m/s initially propagates toward a quadrupolar electrostatic mirror. The H atoms are then photoexcited to n=27 Rydberg states with a positive Stark shift and move in a rapidly increasing electric field. The H atom beam is stopped in 4.8 micros, only 1.9 mm away from the photoexcitation spot, and is then reflected back. The reflection process is monitored by pulsed field ionization and imaging.