排序方式: 共有42条查询结果,搜索用时 31 毫秒
21.
A novel hybrid surface micromachined segmented mirror array is described. This device is capable of scaling to large apertures for correcting time-varying aberrations in laser applications. Each mirror is composed of bottom electrode, support pan, and mirror plate, in which a T-shaped beam structure is used to support the mirror plate. It can provide mirror with vertical movement and rotation around two horizontal axes. The test results show that the maximum deflection along the vertical direction of the mirror plate is 2μm, while the rotation angles around x and y axes are±2.3°and±1.45°, respectively. 相似文献
22.
23.
24.
光学记录系统的组成,有光源为单一模式的半导体激光器、准直物镜、柱面扩束物镜、旋转多面体、fθ透镜及光敏介质。在不修正半导体激光器象散值Δs时,准直物镜的焦点基本上位于半导体激光器的垂直平面光束原始发散点位置上;柱面扩束物镜仅在激光器的平行平面上具有光焦度,其倍率Γ应满足于关系式;光敏介质应位于fθ透镜后焦点附近。 相似文献
25.
26.
27.
基于小波变换的最小二乘相位解缠算法 总被引:1,自引:2,他引:1
最小二乘法是求解二维相位解缠问题最稳健的方法之一,其本质是在最小二乘意义下使缠绕相位的离散偏导数与解缠相位的偏导数整体偏差最小,并等效为可求解一大型的稀疏线性方程系统。由于系统矩阵结构的稀疏性,在采用迭代法求解时收敛速度非常慢。为了改善收敛特性,提出一种基于多分辨率表示的离散小波变换相位解缠算法。利用小波变换将原线性系统转化成具有较好收敛条件的等价新系统。仿真实验表明,该方法能够很好的恢复真实相位,其解缠效果优于Gauss-Seidel松弛迭代和多重网格法。 相似文献
28.
29.
Attenuation characteristics of a light attenuator combined by polarizers with different extinction ratios 下载免费PDF全文
This paper deals with a systematical analysis and an algorithm of attenuation characteristics of a light attenuator combined by n pieces of polarizers (n-LACP) whose extinction ratios are different from each other.The attenuation ratio expression of a two-LACP is deduced.We find that the monotonic attenuation interval depends on the first polarizer and that the attenuation range depends on the second one.For the three-LACP,a method for obtaining a monotonic attenuation interval is proposed.Moreover,the attenuation ratio expression is demonstrated.Analysis and experiment show that when the initial status of the three-LACP is at the maximum output,if the second or third polarizer rotates alone,the minimum attenuation ratios can reach K-1 2 and K-1 3,respectively,and if the first polarizer rotates,a minimum attenuation ratio of K-1 2 K-1 3 can be obtained (K 1,K 2 and K 3 represent the extinction ratios of the three polarizers in turn).Furthermore,the attenuation ratio expression of n-LACP and the relevant attenuation characteristics are proposed.The minimum attenuation ratio of an n-LACP is (K 2 K 3 ··· K n)-1. 相似文献
30.
介绍了基于微机电系统技术的微变形反射镜的基本结构和电极分布.分析了微机系统变形镜的变形原理,推导了微变形镜的镜面变形与外加驱动电压的关系.分析了基于计算机控制的频闪显微干涉测量系统的组成及测试原理,并利用该系统实现了对微变形镜静态电压-位移曲线、静态面形、动态离面变形以及谐振频率的测试.实验表明,测试结果与理论分析有很好的一致性. 相似文献