光盘基片聚合物材料的研究进展

基于对光盘基片研究与生产的需要,在对光盘进行必要的分类及基本工作原理介绍的基础上,对目前常用的诸如PMMA、PC、PS等光盘基片材料的主要性质进行了总结,重点讨论了它们的光学性质。同时,也介绍了一些用于光盘基片的新型聚合物材料的研制动态。     

直流磁控射中Ａr气压强对ＴbFeCo磁光薄膜均匀性的影响

本文研究了磁光盘生产中Ａr气压对直流磁控溅射ＴbFeCo磁光萍膜均匀性的影响,通过调整溅射气压来提高薄膜的厚度均习性和成分均匀性,在靶－基片距离为600mm,溅射功率为６００Ｗ,溅射气压为０．６~0.8Ｐa的条件下,获得了均匀性良好的磁光薄膜,并将此工艺参数用于磁光盘的生产。     

130mm磁光盘预格式信息的测试与分析

本文对130mm磁光盘的导向槽和预格式区的记录信息位进行测试,并对其结果作了分析和讨论。     

浅谈影响高速公路沥青路面平整度的因素

高速公路行车密度大、车速高,为确保行驶车辆的安全和舒适性,对路面平整度的要求很高。部颁《公路沥青路面施工技术规范》(JTJ032-94)要求用连续式平整度仪测定的路面平整度σ≤1.8mm,沪宁高速公路为了创国优,提出了下面层σ≤1.8mm,中面层σ≤1.2mm,上面层σ≤1.0mm的标准要求。由于影响沥青路面平整度的因素很多,对每一个因素的忽视都将对沥青面层最终的平整度产生影响,因此要达到上述标准是有一定难度的。笔者通过对沪宁高速公路无锡段沥青路面的施工实践,从施工角度对影响沥青路面平整度的有关因素作如下分析。     

磁光盘记录光场畸变分析

运用光波衍射理论，针对磁光盘建立了记录光场的数学模型。该数学模型可全面描述基片杂质大小、位置、透射率对记录光场的影响。利用该数学模型可进一步研究基片杂质与磁畴特性，以及盘片误码的关系。     

超高真空中SrTiO3薄膜同质外延生长的过程研究

在超高真空下利用激光分子束外延(LMBE)方法基于SrTiO3(100)单晶基片同质外延SrTiO3薄膜.通过反射式高能电子衍射(RHEED)对生长过程进行原位监测,发现对基片的预热处理明显有利于改善其晶面结构,当在其上同质外延SrTiO3薄膜时,容易实现单晶层状生长模式,并得到原子级平整度的铁电薄膜.     

不同化学蚀刻法对石英基片激光损伤阈值的影响

为提高三倍频光学元件的表面损伤阈值,采用了不同方式对石英基片进行酸蚀刻,利用原子力显微镜观测了基片蚀刻前后的表面微观形貌,并在激光损伤测量装置上进行了R:1方式的阈值测试,比较分析了蚀刻前后基片激光损伤阈值和表面形貌的变化,并比较了不同抛光质量石英基片蚀刻效果的差异.通过实验研究,总结了不同蚀刻方式的优缺点,研究表明酸蚀刻法可以有效提高石英基片激光损伤阈值.     

无支撑、光学级MPCVD金刚石膜的研制

利用引进的6 kW微波等离子体化学气相沉积设备,进行了无支撑金刚石膜工艺的初步研究。在800~1050℃的基片温度范围内,金刚石膜都呈(111)择优取向;基片相对位置对沉积较大面积、光学级金刚石膜至关重要。制出0.25 mm厚Φ50 mm的无支撑金刚石膜。拉曼光谱和X射线衍射分析表明,合成的金刚石膜晶体结构完整,sp2含量极低;透过率测试结果说明了优良的光学性能:截止波长225 nm,光学透过率(λ≥2.5μm)≥70%。     

直流磁控溅射中Ar气压强对TbFeCo磁光薄膜均匀性的影响

本文研究了磁光盘生产中 Ar气压强对直流磁控溅射 Tb Fe Co磁光薄膜均匀性的影响 ,通过调整溅射气压来提高薄膜的厚度均匀性和成分均匀性。在靶 -基片距离为 6 0 0 m m,溅射功率为 6 0 0 W,溅射气压为 0 .6～0 .8Pa的条件下 ,获得了均匀性良好的磁光薄膜 ,并将此工艺参数用于磁光盘的生产     

钙钛矿型氧化物SrTiO3/BaTiO3多层膜的激光分子束外延生长研究

用激光分子束外延技术在SrTiO3(001)衬底上外延生长SrTiO3/BaTiO3多层膜,通过反射式高能电子衍射(RHEED)原位实时监测并结合原子力显微镜(AFM),研究了不同基片温度下所生长薄膜的表面平整度,利用X射线衍射(XRD)对外延薄膜进行了结构分析,结果表明薄膜具有二维生长模式,在基片温度为380～470℃之间生长的薄膜具有原子级光滑,并且具有完全C轴取向.同时运用X射线光电子能谱(XPS)研究了薄膜界面的互扩散,结果表明降低制备薄膜时的基片温度有利于减少互扩散.     

Subtle effects of the substrate in optical disk data storage systems

Much attention has been focused on the effects of the disk substrate in optical data storage. In particular, substrate birefringence has been studied extensively because it causes significant problems in magneto-optic systems. We investigate certain subtle effects of the substrate, such as feedback into the laser diode, in compact disk and phase-change systems. Our analysis of the compact disk system led us to discover a new technique for the rapid measurement of the substrate birefringence. We also address the question of how focusing the laser beam through the substrate will affect the depth of focus.     

Optimum depth of the information pit on the data surface of a compact disk

Abstract

The substrate of a compact disk with data storage structure (pits and lands) on one side is part of the read-out system. One would not expect the optimum pit depth to be a fixed value (a quarter wavelength, as is customarily assumed) because this value is independent of the parameters of the optical system. The quarter wavelength value is based on an inappropriate plane wave model. A model has been developed, based on the interference of converging spherical waves, for the optimum depth of the information pit on a compact disk. A simple expression was found that gives the dependence of optimum pit depth on parameters of the read-out system. In different systems the optimum pit depth will, in general, differ, ranging from a half wavelength to much smaller values. The results provide a theoretical basis for the optimum design of future systems with higher storage densities. In the present paper, the analysis is extended and several diagrams are presented, which show the dependence of detector signal contrast on system parameters.     

Double-disk solid-phase extraction: simultaneous cleanup and trace enrichment of herbicides and metabolites from environmental samples

Phenylurea and triazine herbicides, including some metabolites, were isolated from water and soil extracts by solid-phase extraction using a layered system of two extraction disks, a method called double-disk solid-phase extraction. The first disk consisted of strong anion exchange (SAX) of 10-micron styrene divinylbenzene (SDB) particles embedded in Teflon, and the second disk was a C18 disk of 10-micron particles also embedded in Teflon. A volume of 500 mL of water or aqueous soil extract is passed through the layered system with the SAX disk first. The purpose of the SAX disk is to remove the humic and fulvic acids from the water or aqueous soil extract by ion exchange through their carboxyl groups. Even during methanol elution of herbicides, the humic substances remain bound to the SAX disk with > 85% retention. Elution with methanol results in more than 90% recovery of the herbicides from the layered extraction disks. Removal of the humic and fulvic acids results in greater sensitivity for diode array detection quantitation (0.05 micrograms/L for herbicides) by substantially reducing the absorbance of the humic peak on the LC chromatogram. The herbicides adsorb to the SAX disk either through hydrogen bonding to the anion-exchange sites or by hydrophobic interaction with the SDB surface of the anion-exchange disk. The method was tested for the analysis of natural water samples from the Mississippi Embayment, a cotton-growing area of the southeastern United States.     

Permalloy disk replicator for amorphous film 2 µm bubble devices

A permalloy disk replicator in an amorphous film 2 μm bubble device has been Studied for different geometrical dimensions, and from quasi-static to 200 kHz operating frequency. Distinct regions of the margin plot are observed, and their dependence on geometry is analyzed. It is found that for reliable replication over a wide margin range, the poles from the replicator disk, from the neighboring propagation channel, and from the previously replicated bubbles must be carefully balanced. A replicator with 20% margins on 2-micron GdCoMo films is shown and methods for further improvements are discussed.     

An Empirical Investigation into the Distribution of Flatness Measurements

The flatness of individual components can critically influence the fit or lack-of-fit of compact, small assemblies. To ensure high yield, flatness is tightly toleranced and controlled. According to the standard definition of flatness, the underlying distribution of flatness measurements should be asymmetric. In this paper, 20 industrial flatness data sets from four different processes and three different materials are examined. To accommodate measurement round-off and small sample sizes, the Moran log spacing statistic is used to test if the normal distribution provides an adequate fit. The results demonstrate that the symmetric normal distribution provides an adequate fit for all the data sets. Such a result is important in confirming the use of root-mean-square tolerance analysis techniques, as well as selecting process monitoring and summarizing statistics.     

铝表面钽／镝／铅复合涂层组织结构的研究

在铝材基体上,综合应用等离子喷涂和电弧喷涂等热喷涂方法,喷涂钽,镝,铅等材料,制备具有辐射屏蔽效应的多层复合涂层,用光学显微镜和ＳＥＭ对复合涂层的组织结构进行了观察分析,定量分析了涂层的化学成分,测量了喷涂样品的平面误差和涂层重量,结果表明,涂层之间结合紧密,组织均匀致密,孔隙率低,满足了辐射屏蔽要求,达到了预期效果。     

温度对平晶平面度影响的定性分析及相关问题探讨

在测量平晶工作面的平面度时,温度不仅对平晶平面度的大小有影响,而且直接影响对平晶表面形状（凹凸）的判断。文章给出了温度对平晶平面度影响的实例分析,并提出了两种平晶表面形状判断的辅助方法,且对JJG28—2000《平晶》检定规程中平晶表面形状判断方法进行了必要的补充说明。     

大型硅晶片平面度精密纳米计量技术

描述了一种基于斜率传感器的大型硅晶片平面度扫描测量系统．采用二维斜率传感器对晶片表面扫描，以获得表面绕X和Y轴的倾斜度．斜率传感器装在X向滑板上，而晶片固定在可绕Z轴转动的主轴上．对斜率传感器Y向的输出积分，得到晶片表面各个同心圆上轮廓截面高度．对斜率传感器X向的输出积分，得到晶片表面沿X向的截面轮廓，从而获得各同心圆轮廓之间的关系．构建了一个包括基于自准直原理的小型斜率传感器、气浮主轴、气浮导轨的实验系统，提出一种斜率传感器现场标定方法，用此系统测量了直径300mm的硅晶片平面度。     

Dual-wavelength optical head with a wavelength-selective filter for 0.6- and 1.2-mm-thick-substrate optical disks

A dual-wavelength optical head, believed to be new in design, for 0.6- and 1.2-mm-thick-substrate optical disks was developed by use of 650- and 780-nm-wavelength light and a wavelength-selective filter, which reduces the spherical aberration that is due to the difference in substrate thicknesses and restricts the numerical aperture for 780-nm-wavelength light. According to this configuration, both high light power efficiency and wide image field characteristics are obtained, which are suitable not only for read-only but also for recordable or rewritable optical disk systems. A reading operation for a digital video disc and for a compact disc and a recording operation for a phase change optical disk were successfully demonstrated.     

光盘振动模态的电视激光全息测量与分析

采用激光全息(TV—holography)振动测试技术测量和分析了CD光盘的固有频率、模态振型以及模态分布情况。采用非接触声激励和非接触式激光全息摄像精确地测量出了CD光盘从零节圆到三节圆五节径的振动模态，最高模态频率达6300Hz。分析了节径振型和节圆振型间的关系和出现规律。结果表明：光盘的振型节线是由中心对称和轴对称的节径和节圆组成的，它们对应的振型也是中心对称和轴对称的；光盘的各阶固有频率是按一定的顺序排列的，节径和节圆的出现是有规律的，文中给出了表示这些规律的表达式。