改进的斑点法测量自聚焦透镜光学参数

改进的斑点法测量自聚焦透镜的主要参数是利用直径不同的近轴平行光束垂直入射到自聚焦透镜端面，在出射端面测量光束光斑大小之差，从而确定了自聚焦透镜的周期长度ｐ，焦距ｆ以及中心折射率ｎ０和分布常数Ａ。     

用斑点法测量自聚焦透镜光学参数

本文通过对自聚焦透镜射线轨迹的分析,提出了使用斑点法测量自聚焦透镜各种光学参数。这种方法原理清晰,设备简易,操作方便。是—种很有价值的测量方法。     

LD光束经自聚焦透镜变换后的特性研究

通过两种方法对二极管经过自聚焦透镜的光束变换规律进行了分析，利用计算机模拟了自聚焦透镜的输出端沿轴线任一点的光斑形状，从而给出了自聚焦透镜输出光束的特性，并讨论了它对二极管端面泵浦耦合光学系统效率的影响。     

光纤和自聚焦透镜的端面检查

本文描述了自聚焦透镜的一种检查方法，用来测定光纤和自聚焦透镜的端面质量，同时可测定光纤的数值孔径（NA）。该方法简单易于操作，适用于设备较小的条件下使用。     

激光二极管的自聚焦透镜耦合理论与设计

分析了自聚焦透镜对激光二极管(LD)远离透镜主轴的大发散角光束的耦合公式,利用光线追迹法得到了用自聚焦透镜耦合时自聚焦透镜各个参数对耦合结果的影响,从而得到了获得较小聚焦光斑时的自聚焦透镜的最佳参数及在测量面上的相对输出光强分布。为利用自聚焦透镜耦合大发散角的激光二极管光束提供了参考依据。     

自聚焦透镜光学加工研究

本文主要通过自聚焦透镜光学加工研究,介绍一种比较合理实用的加工方法,用这种方法加工成的自聚焦透镜可达到很高的光学质量指标和尺寸精度。本文还对简易而实用的小直径圆柱形透镜端面与其母线垂直度测量方法作了具体分析和阐述。     

一种改进的中值滤波方法及其在自聚焦透镜端面图像特征提取中的应用

针对自聚焦透镜端面图像的特点,本文提出了一种改进型中值滤波方法,并应用该方法进行了图像缺陷特征的提取实验。文中详细介绍了改进中值滤波方法的基本原理,包括模板取值规则、位置设定及比较试验结果。另外,给出了实验装置的构成及原理,针对自聚焦透镜表面缺陷所进行的一系列的图像处理实验,包括阈值分割及缺陷形态学统计等,实验结果证明了该方法的有效性。     

端面球透镜光纤与激光器的耦合

一、前言激光器与光纤的耦合在光通信系统中占有比较重要的地位。如何提高耦合效率以及改进耦合器的结构性能是最近几年中耦合器研制方面的主要课题之一。对此,国内外都进行了许多研究,取得了很大的进展。特别是激光器与光纤的耦合,在耦合方式上有端面球透镜、锥状透镜、柱透镜、自聚焦透镜,以及这些透镜     

自聚焦透镜列阵调制传递函数的测量

介绍了白聚焦透镜列阵（SLA）成像的特点和制作自聚焦透镜列阵的主要考虑因素，分析了通过测量自聚焦透镜列阵调制传递函数（MTF）来评价其成像质量的可靠性。对调制传递函数的测量原理和方法进行了介绍，分析了用该函数评价自聚焦透镜列阵成像质量合理性的主要依据，从理论上给出了自聚焦透镜列阵的调制传递函数值随波长和空间频率变化的曲线图，并分析了测量值与理论值之间存在差距的影响因素。实验测得A和B两种类型的自聚焦透镜列阵当共轭距（TC）设计存红光波段时，其调制传递函数值分别为58．57％和60．78％，同时测得绿光波段为52．03％和56．34％，蓝光波段为49．94％和53．01％。实验结果显示，B型透镜列阵的成像质量要优于A型。     

自聚焦透镜列阵象平面上的辐照度与曝光量

本文分析了单位放大率成象条件下自聚焦透镜及其列阵在朗伯光源照射时，象面上的辐照度与曝光特性。自聚焦透镜的长度对辐照度和曝光量的大小与起伏有密切联系。讨论涉及单根自聚焦透镜和一列、两列透镜列阵。选择适当的透镜长度，可兼顾辐照度与曝光量的大小与起伏，从而获得较满意的象质。由自聚焦透镜列阵的曝光量要求可确定复印设备中使用的光源强度和扫描速度。本文对单根、一列、二列自聚焦透镜列阵的辐照度作了实验测量，所得结果与理论分析较好地符合。     

光学系统基于质心的色差矫正

在成像光学系统的设计过程中必须对其垂轴色差进行校正.在一束特定成像光束所形成的弥散斑上,作色差计算的光斑中心不是主光线与像面的交点,而应该是弥散斑中所有光线交点的"重心"所在,也就是所谓的质心,它是由被追迹的光线的分布和数量决定的.本文介绍了如何基于质心计算垂轴色差,提供了在ZEMAX中编写的计算参考波长质心坐标的宏程序,有助于设计结果与实际情况的进一步吻合.     

Air core coils for deflecting micron-size electron beams

Bobbin-type air core coils have been designed and experimentally evaluated for astigmatic properties in line scan operation over deflection angles of ± 20°. The approximate design technique is successful in specifying the proper operating focal distance when this is comparable to the coil length. Line fields in excess of 20 000 spot diameters have been measured using a 10 kV beam having a 5 × 10-³radian convergence half-angle.     

深紫外CMOS图像传感器测试匀光系统设计

匀光系统的均匀性是实现深紫外CMOS图像传感器参数测试的关键。根据傅里叶光学理论,结合ArF准分子激光输出光斑特点,设计了复眼阵列匀光系统的初始结构,并在ZEMAX非序列模式下建立了匀光系统模型。针对ZEMAX光源中光线采样随机性的特点及匀光系统均匀性的要求,对追迹光线数目及复眼阵列中透镜元个数进行了优化。在透镜元大小为1mm、采用1亿根光线并做30次平均后,在12mm×12mm光斑范围内获得了均匀性为0.986的均匀照明光斑,满足CMOS图像传感器测试对光斑均匀性优于0.97的要求。     

激光粒度仪光学系统设计方法

以米氏散射理论为依据,提出了一种可以提高激光粒度仪测量精度的光学系统设计方法。该方法设计激光粒度仪光学系统时,光阑位置在激光粒度仪测量区域内采用变焦方式,同时控制每个视场上光线、主光线和下光线在接收器件-环形光电探测器的位置,控制光阑位置变焦时每个视场上光线、主光线和下光线在接收器件位置,使测量区域内散射角相同的光线形成的弥散斑最小。光学系统对光线的会聚真实地体现了激光粒度仪的测量理论的物理意义,提高了激光粒度仪的测量精度。     

A high-resolution electron gun for thermoplastic recording using prefocus deflection

A demagnification gun of high resolution was developed for thermoplastic recording by deflecting the electron beam at the entry of a large focusing lens. The unconventional approach of prefocus deflection allows close spacing between the "short" focusing lens and the target (phosphor screen or thermoplastic tape) required for demagnification and results in a gun with a relatively short length. The diameter of the focusing lens is about three times larger than the 25-mm diameter area to be scanned in order to keep spot distortions of the deflected beam at a minimum. Electrostatic focusing combined with magnetic deflection was selected. The special focusing lens that is used is shaped for low aberrations, increased demagnification and increased deflection sensitivity. Small deflection fields are required since the electron beam is being deflected in the accelerating field while the electron velocities are still low. The gun operates at 10 kv and delivers a 5-micron spot at 1µa. This corresponds to a resolution of 5000 spot diameters at average current densities in excess of 5 amp/cm². In spite of the high resolution, the over-all length of the gun measured from the target is only 9 inches.     

激光钠信标光斑漂移和光斑半径的数值模拟与分析

激光钠信标的光斑漂移、光斑半径的变化对自适应光学校正有直接的影响。在激光钠信标光斑漂移方差和有效半径理论模型的基础上,采用数值模拟的方法,在三种大气湍流模式下,具体研究了激光钠信标光斑与激光光斑漂移方差和有效半径的差异,计算了不同发射口径时激光钠信标光斑的长曝光与短曝光有效半径的平均值,分析了有再泵浦能量激光对激发钠信标光斑漂移方差和平均有效半径的影响。研究结果表明,大气湍流强度、激光发射口径以及再泵浦激光能量都能够影响激光钠信标光斑漂移和光斑半径。     

用蒙特卡罗方法和MATLAB计算冷屏内壁表面辐射光线在探测器芯片上的分布状态

以圆形冷屏中的640×512面阵器件为例,基于几何光学的基本原理,将冷屏内壁表面辐射抽象为一定数量、可用MATLAB随机产生的几何光线.追踪这些光线的去向,统计出其中直接投射、或者经过一次反射后落入探测器各光敏元的光线数量,通过直方图、散落点图等途径分析冷屏内壁表面辐射光线在探测器芯片上的分布状态.     

A hybrid representation of the Green's function in an overmodedrectangular cavity

A hybrid ray-mode representation of the Green's function in a rectangular cavity is developed using the finite Poisson summation formula. To obtain a numerically efficient scheme for computing the field generated by a point source in a large rectangular cavity, the conventional modal representation of the Green's function is modified in such a way that all the modes near resonance are retained while the truncated remainder of the mode series is expressed in terms of a weighted contribution of rays. For an electrically large cavity, the contribution of rays from distant images becomes small; therefore, the ray sum can be approximated by one or two dominant terms without a loss of numerical accuracy. To illustrate the accuracy and the computational simplification of this ray-mode representation, numerical examples are included with the conventional mode series (summed at the expense of long computation time) serving as a reference     

ULSI中金属互连系统上的热点分析

针对金属互连系统上的热点将对集成电路芯片的性能和可靠性产生重大的影响,详细讨论了ULSI金属互连系统上的热点位置和温度分布模型,并通过该模型比较了不同通孔直径和高度情况下,金属互连系统上的热点位置和温度的差别。结果表明,通孔直径和高度对金属互连系统上的热点有重大的影响。     

Self‐Organized Periodic Microholes Array Formation on Aluminum Surface via Femtosecond Laser Ablation Induced Incubation Effect

Laser surface structuring has been demonstrated to be a versatile technology to create various functional materials by modifying solid surface properties. An interesting experimental phenomenon of self‐organized periodic microholes array formation is demonstrated by exposing an aluminum surface to femtosecond laser irradiation. The microholes with a diameter much smaller than focal laser spot size are produced along laser scan paths due to the incubation effect of multiple laser scans, and they spontaneously form a highly ordered microholes array after 80 scans. It is found that the microhole period and diameter are highly dependent on laser fluence, and controllable microholes arrays with different periods and diameters are achieved by adjusting laser fluence. The physical mechanism behind the formation of the microholes array is attributed to femtosecond laser‐induced melting and Marangoni effect. The research provides a novel processing approach to achieve controllable microholes surface materials fabrication at a high speed on metal substrates, which are of great interests for various technological applications.