大型干涉仪镜子的支承设计与温度变形分析

在星间激光通信中,涉及对大口径衍射极限激光波面的检测,为保证测量精度,必须严格控制波面干涉仪镜子的自重和温度变形。采用有限元方法对大型干涉仪镜子在不同支承方式下的表面变形进行了分析,结果表明,接触角为180°的钢带支承是较好的支承方式,反射镜表面变形峰谷(PV)值仅为1.35nm,均方根(RMS)值为0.363nm。根据这一结论,设计了一个固定支承点与浮动支承相结合的超静定钢带支承结构。在该结构下,分析了镜子轴向、径向、周向的温度梯度效应,分析数据表明,镜子的热弹性变形远大于自重变形,建议采取一定的温控措施,并采用平均效应的方法降低热效应的影响。     

Corrected mirror systems with double reflection

We propose objectives consisting of two mirrors with central holes for passage of a light beam. The optical layout ensures multiple reflection of rays from both mirrors. We consider several approaches to calculating the design parameters for which three and four aberrations do not occur. The objectives can be used in optical devices operating in the UV and IR regions of the spectrum. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 2, pp. 267–270, March–April, 2007.     

平面反射镜表面散射光干涉

激光束照射到表面被粘污的反射镜上会产生干涉环,入射光束和反射光束在被粘污表面产生散射光干涉.随着入射角的变化,光束在反射镜玻璃片内光程改变,引起干涉环从中心冒出或缩进,干涉环级数的变化与入射角的平方成正比.     

Structural optimization design for large mirror

The system design must be started from the concept with low cost and high performance. In this point, the topological shape of the structure is very important in the view of the structural rigidities and light-weight design.In this paper, the optimization methodology is presented in the design stage of the large optical mirror. We obtain the optimal layout through the topology optimization and then design the details through the size or shape optimization for structural rigidity.     

线电荷与接地半无限大导体板所形成的电场

将镜像法和保角变换法相结合,计算由线电荷与接地半无限大导体板所形成的电场,给出其电势分布和场强分布,进一步得出等势线方程和电场线方程,并利用数学软件MATLAB绘制出等势线图和电场线图.     

一种离轴凸双曲面单修加工及检测方法的研究

离轴凸双曲面的加工和检测是非球面加工检测中的一个比较困难的问题.结合一块口径φ230mm、离轴量226mm的凸双曲面镜,提出了离轴凸双曲面镜单修加工以及采用离轴Hindle球检测偏转角度的离轴凸双曲面镜这一方案.给出了单修加工工艺,并解决了检测光路的搭建难点.加工完成的离轴凸双曲面的面形精度RMS优于λ/50(λ=63...     

A high-precision 1D dynamic angular measuring system based on linear CCD for Fengyun-2 meteorological satellite

The Fengyun-2 (FY-2) meteorological satellite uses a one-dimensional dynamic angular measuring system to evaluate the stepping accuracy of the scanning mirror. The basic principle of this angular measurement is detecting the light-spot position displacement using a linear charge-coupled device (CCD). This paper presents the design of this non-contact and non-destructive measuring system. To achieve high repeatability and accuracy the centroid method is employed to estimate the light-spot energy gravity, with 20-segment polygonal approximations as a nonlinear compensation. Experimental results show that the measurement system can achieve dynamic angular measurement with up to ±5″ accuracy and 3.5″ repeatability, which makes a credible evaluation for the scanning mirror of FY-2 meteorological satellite.     

Athermal metal-free planar waveguide concave grating demultiplexer

An athermal metal-free planar waveguide concave grating demultiplexer is proposed. We designed the dielectric mirror at the grating facet instead of coating with the metal on the back wall of the grating facet. The transfer-matrix method is introduced to design the dielectric mirror and the reflectance spectral responses of the 2D waveguide structure are simulated using the FDTD software (RSoft, Inc.). To reduce the temperature sensitivity of the device, the three-focal-point method is introduced. We use the design example to show the high-reflectance bandwidth of the dielectric mirror. The fabrication errors are also taken into consideration. By using the numerical model of the scalar diffraction theory, the flat-top spectral responses of the channels are simulated.     

具有有源闭合腔的光纤光栅传感系统地址查询技术

基于熔融拉锥技术研制的3 dB宽带耦合器的光纤环形镜的工作原理,提出了一种新型的具有有源闭合腔装置的光纤光栅传感系统。在用作闭合共振腔端镜的环形镜中写入十个波分复用光纤光栅传感元,利用共振腔中接入的法布里-珀罗滤波器,通过控制电压对传感光栅的波长扫描,实现对传感地址的查询。用非平衡的迈克耳孙扫描干涉仪将传感光栅的波长漂移信息变为相移信息,实现传感信号的解调。系统传感灵敏度的实验值为1.5835°/10-6ε,与理论值(1.6662°/10-6ε)基本吻合。     

用多面体测试分度误差研究

采用多面体和光电平行光管测试圆刻机分度误差，比较了１２、３６、７２面体的测试特点，从数据分析中可找到一些造成误差的因素