【摘 要】
：
A novel pre-collimating scheme in laser-focused chromium (Cr) atomic deposition is presented. It consists of three apertures, which are one main pre-collimating aperture at centre and two probing apertures with uniform dimension at both sides of the centr
【机 构】
：
DepartmentofPhysics,TongjiUniversity,Shanghai200092
【出 处】
：
ChineseOpticsLetters
论文部分内容阅读
A novel pre-collimating scheme in laser-focused chromium (Cr) atomic deposition is presented. It consists of three apertures, which are one main pre-collimating aperture at centre and two probing apertures with uniform dimension at both sides of the central one. The calculations show that the Cr atomic beam is divided into three parts accordingly after going through this scheme, and the full-width at half-maximum (FWHM) of each part decreases while the peak value increases after one-dimensional (1D) Doppler laser collimation, subsequently. Compared with that before laser collimation, the central part does not have displacement, but each part of the other two has the same displacement to the centre after laser collimation. These phenomena which are agreed with experiment prove that the novel pre-collimating scheme is a feasible means to solve the problem which we cannot observe the collimation of Cr atomic beam after substrate in laser-focused deposition with a pre-collimating scheme of only one aperture, because the atoms will be obstructed completely by the substrate.
其他文献
An all-optical wavelength reuse technique employing cost effective power efficient vertical surface emitting laser (VCSEL) is proposed to address uplink data streaming from end-users by exploiting the same wavelength assigned to them. A saturated optical
根据光电探测器的"猫眼效应",针对成像光学系统的视轴,从理论上分析了利用激光对超视距系统进行视轴对准的可行性,特别分析了激光器输出功率参数、接收探测器焦平面是否离焦等关键参数.研究结果表明,基于"猫眼效应"的超视距系统进行视轴对准在理论上和实验设计上是可行的.
近年来,深度学习在图像超分辨重建方面表现出色。然而,由于复杂的海洋环境,传统的图像超分辨算法存在着调节参数困难等问题,单帧图像超分辨率算法亦存在病态的恢复,生成的像素点具有不确定性。提出了一种多帧图像的超分辨重建算法以用于海面图像重建研究,利用深度学习中的卷积神经网络来学习多帧低分辨率图像与高分辨率图像之间的映射关系,从而实现超分辨率重建。同时,由于海洋监测成像系统需要更多的高频信息来判别目标及锁
所谓分子分光学，就是使用能产生光或微波的“光源”以及能测量它的波长或频率的分光器，以分析分子的频谱，并求得能级构造的一种过程，这是最标准的叙述方式。显然就“光源”而言，要求能得到任意波长的“强”辐射；就分光器而言，要求对波长或频率的测量精度好，分辨率高。在作实验时精力也应该放到这些方面。
设计并搭建了一种基于复合型液晶空间光调制器(LC-SLM)的自适应光学原理校正系统,其中一个空间光调制器用于波前模拟,另一个用于波前校正。利用Zygo干涉仪对畸变波前进行了检测,通过程序计算获得了畸变波前的共轭波前,产生了相应的灰度图,将其加载到LC-SLM以进行畸变波前补偿,实现了静态波前校正。计算得到的斯特列尔比由校正前的0.3795增大到0.8268,环围灰度平均值由校正前的382.75增大到1164.5,光斑亮度聚集情况明显改善。相比纯相位空间光调制器,复合型空间光调制器节约了成本,适合实验室批量
研究了角反射器阵列形成赝相位共轭波的能力,计算了其对泽尼克多项式表示的各阶像差的保真度;分析了在共光路共模块自适应光学系统中角反射器阵列与哈特曼夏克波前传感器二者之间单元数目、位置匹配方面的问题,对失配所带来的误差进行了计算.
A finite element model was constructed using a commercial software Fidap to analyze the Cu-base filler metal droplet spreading process in laser brazing, in which the temperature distribution, droplet geometry, and fluid flow velocity were calculated. Mara
基于表面等离子激元自发辐射放大噪声系数理论, 研究了长程表面等离子激元噪声系数变化规律, 设计了嵌有金属条的长程表面等离子结构.数值模拟得到表面等离子及周期条状长程表面等离子的噪声系数变化规律.给出入射波长从0.5 μm到1.75 μm, 每隔0.25 μm的噪声特性, 发现随着波长的增加噪声系数趋近于常数.仿真结果表明: 表面等离子及长程表面等离子自发辐射放大的噪声系数随着增益介质增大而明显增强；周期条状长程表面等离子结构中, 随着金属膜厚度以及金属条高度及个数增加导致噪声系数增加, 其中金属膜厚度对于