新型复合补偿器研究

本文给出了一种新型复合补偿器,它由两个λ/4波片和一个λ/2波片组成。利用琼斯矩阵方法对其进行系统的研究,结果表明其延迟量连续可调,满足补偿器要求。实验测量结果与理论结果相符。     

三元复合式消色差补偿器的研究与测试

光学补偿器是一种光相位可在一定范围内连续可调的延迟器件,是偏光技术中的一个重要光学元件。对于三元复合式补偿器来说,只需转动其中的一个波片便可实现延迟量在0～2π之间连续可调,而且调节方便,调整量大,精度高。本文在复合式补偿器研究基础上,进一步从理论和实验上证明了该补偿器不仅具有相位补偿性能,而且在一定的光谱范围内满足消色差性能,削弱了延迟量对波长的依赖关系,适合于复色光使用。     

基于PLC的PMD补偿器中PDL效应的分析

应用穆勒（Müller）矩阵对硅基平面光波导线路（Planar lightwave circuit PLC）补偿器中PDL对差分群时延(Differential group delay DGD)分布的影响进行了分析,在不同的PDL值下对各种不同级次的PLC单元级联情况的DGD值分布进行了讨论,并与Maxwell分布进行了比较,得到了在特定PDL值情况下最为优化的PLC级次.     

近红外偏振干涉相位补偿器的稳定性

相位补偿器是偏振干涉仪的核心部件,其稳定性直接影响偏振干涉光谱仪的可靠性.本文分析了相位补偿器的光程差相对灵敏度、光楔倾斜误差、斜入射角误差和温度适应性等指标,并给出相应的误差容限计算公式.研究表明:相位补偿器移动光楔沿运动方向的抗干扰能力是经典迈克尔逊干涉仪的2/Δnsinθ倍,抗倾斜能力是经典迈克尔逊干涉仪的1.75/Δn倍;当入射光以微量倾斜误差入射后,相位补偿器不会产生额外的附加光程差;―20~85℃范围内的温度变化对相位补偿器产生的最大光程差误差为1.8μm,具有很高的热稳定性;当光楔角为30°时,干涉仪在性能、尺寸和成本之间达到均衡;晶体材料的双折射率差通常远小于1,偏振干涉的稳定性更加明显.本研究为相位补偿器在更为复杂的环境中的应用奠定了基础.     

非球面零检验的镜式补偿器设计

根据三级像差理论，推导镜式补偿器在检验光路中初始结构参数计算公式，讨论计算机最佳优化设计方法，并给出设计实例。     

石榴石型偏振调节器温度效应研究

采用磁控溅射法制备了石榴石型偏振调节器并研究了温度对其的影响.利用斯托克斯偏振仪和CCD,研究激光透过石榴石及石榴石型偏振调节器的偏振极化性质和光斑变化.实验结果表明:在25～75℃温度范围内,激光穿过不同材料时,斯托克斯参量变化趋势不同;但是因方位角不改变,激光的偏振度、线偏振度、圆偏振度基本不变.     

1/4波片延迟量的相位调制椭偏测量法

利用椭偏测量术中的相位调制椭偏测量原理测量了1/4波片的延迟量。该方法预先对测量光束的偏振态进行调制,以生成随时间变化的光强信号,通过对信号中的谐变成分进行分析而获得待测波片的延迟量。测量了四个波片,其中三个波片的延迟量已经用电光调制法精确测量过,经对比测量的结果符合较好。观察到了和理论相符的云母波片延迟量的振荡现象。实验结果说明这种方法是一种有实际意义的方法。     

特大非球面度离轴非球面补偿器结构设计与装调

针对快焦比特大非球面度离轴非球面反射镜,设计了3片式Offner补偿器。为应对3片式补偿器对中心偏差及镜间隔严格的公差要求,设计了相应的补偿器镜筒结构。该结构使透镜中心倾斜及平移调整相分离,实现补偿器的高精度装调。根据中心偏差测量仪的测量结果,2片补偿镜之间倾斜误差4.4″,平移误差3.5 μm, 镜间隔误差3.8 μm;补偿镜组与场镜之间倾斜误差5.3″,平移误差4.2 μm, 镜间隔误差7.2 μm,满足检测使用要求。利用该补偿器及4D动态干涉仪对精抛光阶段的离轴非球面进行检测,面形结果PVq值达到0.135λ,RMS值达到0.019 5λ,优于设计要求。     

斑马鱼肌肉结构的定量偏振成像

偏振成像可用于表征各向异性肌肉组织,但是常规偏振成像方法只能给出定性的结构形态,无法对肌肉发育过程进行定量的比较。构建了一套定量偏振成像系统,采用两个互相垂直的偏振片同步旋转得到一系列图像,经过图像处理获取斑马鱼每个肌节定量的相位延迟量。该定量偏振图像与光源亮度、曝光时间等无关,可以用来比较不同时间拍摄的斑马鱼肌肉形态和分布。研究发现野生型和肌肉受损型斑马鱼肌肉生长变化过程不同。     

直流电流补偿器

电流补偿器相当一个零内阻的电流测量仪器,可直接测量电流,因此是一种精密测量仪器     

用计算全息标校补偿器的技术

用计算全息(CGH)模拟理想非球面主镜的反射波面,用补偿器对该计算全息进行检验,只要计算全息的制作误差能够满足要求,就能实现直接对补偿器的标校。介绍了计算全息标校补偿器的原理、方法,并进行了误差分析。实验采用电子束制作的计算全息实现了对850 mm F/2抛物面主镜补偿器的标校,补偿器产生的标准非球面精度不低于计算全息模拟的主镜面形精度,均方根(RMS)误差为0.012λ。研究表明,用计算全息模拟主镜反射波面对补偿器进行标校是一种行之有效的方法,结合先进的微电子制造技术,可实现对补偿器的高精度标校。     

Temperature Tuning of Casimir Effect

We theoretically investigate the additional correction to the Casimir effect due to the change of dielectric constant with temperature, which is different from the previous research that have widely taken dielectric constants of materials as a value independent of temperature. It is found that such a correction can go beyond 20% for some cases and it should not be ignored. Due to the prominent correction, it is possible to tune the Casimir force by such an effect.     

Raman Shift Temperature Effect and New Temperature Measurement Method

The existing distributed optical fiber Raman temperature measuring principle is to use the relationship between Stokes and anti-Stokes intensity ratio and temperature to obtain the temperature. However, it is difficult to process the light intensity signal, since the Raman scattering peak intensity is relatively weak. According to the bond relaxation theory and the relationship between Raman frequency shift and bond parameters, a linear relationship between Raman frequency shift and temperature is established. And a new method for measuring Raman frequency shift temperature is proposed. The Raman frequency shift high temperature effects of diamond, graphite, CdS, Bi2Se3 and Sb2Te3 are calculated. These calculation results match well with the experimental ones and the Raman reference frequency and the atomic cohesive energy are obtained. The proposed method effectively avoids the influence of Raman peak strength on temperature measurement and provides a new theoretical method for the rapid development of distributed optical fiber Raman temperature measuring techniques.     

磁光Kerr效应的温度特性研究

从磁光Kerr效应的微观量子表述出发,分别研究了铁磁材料和亚铁磁材料的磁光Kerr效应的温度特性。结果表明,磁光Kerr转角θK与材料磁化强度随温度变化关系不同。铁磁材料θK对磁化强度M的级数展开式中仅含M奇次项。亚铁磁材料可以出现磁化强度M≠0而磁光Kerr转角θK=0情况。     

Influence of Annealing Temperature on Berthelot-Type Hopping Conduction Mechanism in Carbon-Nickel Composite Films

Electrical conductivity of carbon-nickel composite films annealed at temperatures 300,500 and 800℃ is studied over a temperature range of 50-300 K.While the conductivity data above room temperature show extended state conduction,lowering the temperature from 150 to 50 K leads to the Berthelot-type conduction mechanism.It can be seen that the films annealed at 500℃ have the maximum conductivity.The extent of the carrier wave function at 500℃ has the minima 2.87 × 10~(-7) cm and 2.45 × 10~(-7) cm in octahedral-metal stretching vibrations and intrinsic stretching vibrations of the metal at the tetrahedral site,respectively.The average distances between two vibration octahedral and tetrahedral sites at 500℃ also have the minima 1.13 × 10~(-7) cm and 0.97 × 10~(-7) cm,respectively.The Berthelot temperature for films annealed at 800℃ has the minimum of 94.3K.     

温度误差对激光陀螺零偏温度补偿精度的影响分析

分析了温度测量误差对环形激光陀螺(RLG)零偏补偿精度的影响,通过仿真,在动态温度模型中,发现温度测量误差主要通过温度变化率对补偿结果产生影响,提出了该模型在陀螺零偏动态温度补偿中是否考虑温度测量误差的标准。仿真结果表明,对使用的温度补偿模型与温度传感器而言,在温度补偿精度明显小于0.001°/h时,要考虑温度测量误差的影响。     

Effect of Annealing Temperature on Track Diameter

In exposing cellulose nitrate CN85 plastic films to alpha particles derived from a ²⁴¹Am source, track diameters were measured with regard to different annealing temperatures. The results have shown that the diameters of the tracks are decreasing when the annealing temperatures are increasing.

Kunstharzfolien aus Zellulosenitrat CN85 wurden einer Alphastrahlung ausgesetzt, die einer ⁴²¹Am-Quelle entstammten. Es wurden die erzeugten Spurendurchmesser im Hinblick auf die Ausheilungstemperatur vermessen und es konnte gefunden widen werden, daβ die Spurendurchmesser mit steigender Ausheilungstemperatur abnehmen.     

Influence of Composite Effect from Quantum Channels on Entanglement

The dynamics of entanglement between two qubits in the local damping two-sided channel and singlesided channel are compared through non-Markovian process and Markovian process. The entanglement between two qubits is found to be longer in the single-sided channel case due to the weakening of the dissipative effects. In the two-sided channel, influenced by the entanglement between qubits, the previous independent dissipative channels incline to the composite effect of the Markovian process. This composite effect results in the dissipative effect of one channel affecting the qubits in the other channel, especially inhibiting the backflow effect in the non-Markovian channel, which is disadvantageous to the entanglement maintenance between qubits. In the Markovian channel, the composite effect of the damping two-sided channels is more obvious since there is no backflow effect, thus more disadvantageous to the entanglement maintenance.