分割电极片状压电致动器—（二）位移特性及狭缝宽度对其影响的实？…

研究了悬臂梁式分割电极片状压电致动器的位移特性，理论分析表明，分割电极缝宽度会减小致动器自由端的位移输出，但光缝宽度小于致动器电极宽度的１０％时，可忽略狭缝宽度的影响。致动器端部位称的结果大于理论计算值。与现有磁头悬浮臂尺寸相近的致动器在，２０Ｖ－５０Ｖ的电压驱动下均可获得１μｍ－２μｍ的致动位移。对９８５０道／厘米的密度磁盘，该位移能覆盖至少一个磁道宽度，满足磁头定位两级间伺服系统对第二级致动器     

分割电极片状压电致动器——(二)位移特性及狭缝宽度对其影响的实验研究

研究了悬臂梁式分割电极片状压电致动器的位移特性。理论分析表明，分割电极狭缝宽度会减小致动器自由端的位移输出，但当狭缝宽度小于致动器电极宽度的１０％时，可忽略狭缝宽度的影响。致动器端部位移的测试结果大于理论计算值。与现有磁头悬浮臂尺寸相近的致动器，在２０Ｖ～５０Ｖ的电压驱动下均可获得１μｍ～２μｍ的致动位移。对９８５０道／厘米的密度磁盘，该位移能覆盖至少一个磁道宽度，满足磁头定位两级伺服系统对第二级致动器位移的基本要求。     

电子陶瓷薄膜动压悬浮流延的动力学特性分析

为了解决电子陶瓷薄膜的高精密与超薄化流延问题将硬磁盘存储系统中磁头相对磁盘的动压悬浮运动理论运用于电子陶瓷流延过程中,建立了动压悬浮流延法,并给出了流延头相对流延辊子的动静态物理模型.根据该模型所确立的动力学方程式,对其流延过程的动力学特性进行了计算机仿真,获得了系统各参数对流延系统稳定性的影响规律,并利用仿真结果得到实现系统动压悬浮的合理参数,确保了系统的稳定性。     

分割电极片状压电致动器（一）端部位移和电场诱导应力的理论研究

研究了悬臂梁式分割电极片状压电致动器的位移特性。沿厚度方向极化的ＰＺＴ压电陶瓷薄长片，一端固定、一端自由构成悬臂梁。其上下两表面的电极均沿长度方向分割成对称的两部分。施加电场使其中一半在ｄ３１模式作用下伸长，而与其对称的另一半缩短，则压电片沿宽度方向产生弯曲，自由端便可产生致动位移。理论分析结果表明，在适当的驱动电场（不低于１００Ｖ／ｍｍ）作用下，毫米尺寸的致动器可产生微米量级的端部致动位移。电场诱导应力远小于材料的抗张强度。该分割电极压电致动器可用于精密定位，尤其适合在高密度硬磁盘驱动器的磁头定位两级伺服系统中作第二级致动器。     

光刻伺服盘两级定位器测试系统研究

本文从理论上对圆光栅的特性进行了分析及计算,设计出了光刻伺服磁盘两级定位系统位置传感器的执行机构,并采用AMS—200A型人射光干涉显微镜构成磁盘两级定位器定位精度测量系统,通过计算磁头在寻道和定道两个过程的驱动指令运行时间的总和来得到磁盘的平均找道时间,最后通过实验得到磁盘两级定位系统在平均找道时间为24.5ms时的定位精度为0.19μm。     

超声调制电加工系统换能器的特性分析与研究

根据压电振子的动态特性和超声复合电加工振动系统对换能器的要求,设计压电陶瓷换能器;利用ANSYS有限元法对压电陶瓷晶堆进行建模,分析压电陶瓷晶堆的动力学特性。通过ANSYS参数化设计方法,运用多物理场耦合模块分析了压电陶瓷晶堆片数、输入电压信号大小、输出振动位移幅值和晶堆固有频率之间的相互关系,验证了压电换能器设计的合理性及特性分析的正确性。     

数字音频磁盘录制和编辑系统（续上期）

硬磁盘驱动系统图见图5。数据信号经过信道编码和磁头放大电路由磁头进行读或写其内容。磁头自身的前后直线移动是由定位器控制的,定位器的伺服系统提供磁头准确定位。磁盘在马达的带动下旋转,检测信     

昆腾推出便携式计算机用2.5英寸硬磁盘系列

为了给便携式计算机用户提供与台式计算机同样的性能与可靠性,美国昆腾公司(Quantum Cor-poration)最近宣布推出一系列全新的2.5英寸硬磁盘Quantum Europa~(TM),这种新型硬磁盘把磁阻磁头和PRML技术揉合在一起,大大地增加了存储量,提高了性能,并节省了电能。 这套为笔记本型计算机用户设计的硬磁盘有三种规格,分别拥有     

4000TPI光刻面伺服系统的高速寻道机理

光刻伺服盘是一种新的磁头伺服定位技术［１］，通过对４０００ＴＰＩ光刻面伺服系统的光刻伺服图形结构的分析，本文提出了一种简单可靠的磁头过道脉冲检测方式，可显著提高磁头寻道速度，保证磁头在高道密度下高速寻道。     

新型录像机伺服系统故障检修捷径与技巧(上)

<正> 录像机能否正确记录和重放稳定图像,关键在于视频磁头是否准确地跟踪磁迹,而伺服系统则是视频磁头精密跟踪磁迹的重要保证。伺服系统按处理信号的方式可分为模拟伺服和数字伺服两大类。早期生产的录像机一般采用模拟伺服而近期生产的新型录像机均采用数字伺服。数字伺服比模拟伺服具有稳定性高和抗干扰能力强等优点。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks