用于微装配的三维微力传感器的研究

采用硅基应变片设计了一种可用于精密微装配作业过程,检测x、y、z方向微接触力的三维微力传感器;经微小改动后,该传感器可成为五维微力传感器。分析了力传感器测量原理,建立其测量模型,并设计了传感器信号放大电路。测试了微力传感器的性能指标,在x、y、z3个方向的微力测量分辨率为0.001 N,测量精度可达0.005 N,测量范围为-0.5~ 0.5 N。最后设计了微装配作业控制系统,并利用该传感器实现力位移混合控制,顺利完成了180μm微型轴与200μm微型孔间的精密微装配实验研究。     

面向毫克级仿昆扑翼微飞行器的力-力矩传感器

毫克尺度微型仿生飞行器基于柔性高频翅拍运动的升力机制,具有柔性大变形、振动非线性、多自由度力-力矩耦合等特征,其有效升力/力矩范围处于mN/(μN·m)量级,通用力传感器较难准确测定力学参数,进而给微型仿生飞行器的设计与控制带来一定的困难。文章提出了一种面向微型扑翼飞行器的新型力-力矩传感器,它可以在固定约束条件下实现微飞行器高频扑翼运动产生的升力和力矩的测量,为扑翼飞行器控制力和力矩解耦研究提供精度较高的数据。该传感器采用对称式多悬臂梁柔顺机构将升力/力矩转化为微小形变,结合高带宽、高精度电容位移测量装置,可以采集高频振动条件下的微小升力/力矩。基于梁理论进行了传感器力学建模,并结合有限元仿真验证了原理的可行性。对被测对象微型仿生扑翼飞行器的主要测量参数范围开展结构与工艺设计,实验结果显示,该传感器的升力测量范围为-10~10mN,力矩测量范围为-20~20μN·m,特征频率为1kHz,升力和力矩的灵敏度分别为0.01mN和0.01μN·m,经验证,对整机重量在80~250mg、工作频率在1~200Hz范围的微型扑翼飞行器具有较强的适用性。     

一种集成三维微力传感器的微夹持器研制

微操作中力的检测与控制是实现无损伤操作的关键。因此,该文提出了一种以压阻检测技术为基础,集成三维微力传感器的微夹持器。传感器标定实验结果表明,该传感器具有耦合小,测量分辨率高,线性度好的优点。传感器量程为-10~ 10 mN,在x、y向的分辨率均为2.4μN,z向的分辨率为4.2μN。微夹持器采用压电陶瓷驱动两级柔性放大机构,实现张合量300μm,完成了微夹持实验。     

激光位移传感器在物体表面形状测量中的应用

激光位移传感器对位移的测量不仅是非接触式的测量方式,而且具有较高的精度,具有广泛的应用。本文研究了一种利用激光位移传感器测量工件上点的二维坐标,从而实现物体形状的高精度测量。通过一维电位移平台带动激光位移传感器扫描物体的表面,然后对测量的数据进行处理,进而得到物体的表面形貌。实验中采用的位移传感器分辨率为0.3μm,一维电位移平台重复定位精度高于2μm。     

微型反射式横向位移光纤传感器研究

提出了一种测量横向位移的微型反射式光纤传感器，可用于测量物体相对传感器轴线垂直方向的微位移变化量。从光纤出射光场的光强分布函数出发，用数值积分的方法求解出了反射式横向位移传感器的光强调制曲线，进而设计了光纤传感探头和电路。结果表明，传感器的测量线性范围是1mm，分辨率达lμm。     

共光路双频外差干涉法测量模拟磁头磁盘静态间隙

提出了一种共光路外差干涉测量模拟磁头磁盘静态间隙的方法，该方法以低频差横向塞曼双频激光器作为光源，采用专门设计的双折射透镜分光和相位测量技术，实现了对光波半波长的3600细分，从而使测量分辨率达到0．1nm。原理实验结果表明，该系统在无恒温的普通实验室条件下，1h内稳定测量实验结果漂移小于4nml利用压电陶瓷（PZT）微动工作台（步进分辨率1nm）驱动反射镜（模拟磁头）产生位移，在1μm范围内与该系统测量结果进行比对，得到线性相关系数优于0．9998。     

光杠杆式nm级微位移激光测量系统的研究

提出了一种全新的nm级微位移测量方法，改进了传统光杠杆测微位移的原理，研究开发了一种激光微位移测量系统。该方法可以将微位移量放大10^2量级以上，测量系统的理论分辨率为4nm、实测分辨率小于10nm，实验验证了该系统的可行性和可靠性。该系统适用范围广、灵敏度高、重复性好和结构简单，便于构成微电机系统（MEMS），实现系统微型化及自动化。     

一种基于厚膜陶瓷电容的微位移传感器

为深入研究微纳米环境中物体的受力与运动状态,实现微纳米环境下的位置感知与位移操作,建立纳米尺度下位移、力检测的理论方法,研制了一种基于厚膜陶瓷电容的微位移传感器。通过采用厚膜混合集成工艺将信号处理电路与厚膜电容芯片一体化集成,即用厚膜电路替代PCB电路板,以达到降低由于温度效应和寄生电容等导致的非线性误差,提高传感器的分辨率和稳定性的效果。传感器性能标定实验结果表明,0~1 000nm量程范围内位移检测分辨率优于2nm,传感器稳定性得到显著提高,能够用于检测纳米级微小位移变化量。此外,还从材料物理属性和电路优化设计等方面分析了一体化集成的厚膜电路相对于PCB电路板的优越性。     

基于反射式塑料光纤传感器的微位移测量技术研究

近年来,高精度的位移测量精度要求越来越高,为响应这一需求,本文依据待测位移量可由反射光强变化得出的原理设计了一种基于塑料光纤的位移传感器.本文所涉及的光纤位移传感器以静态拉伸式杨氏模量测量实验中钢丝长度的微小变化为待测量进行设计.在整个传感器系统制作完成后,结果显示,在0~3mm的位移范围内,测量输出与实际位移成线性关系且线性度为0.6%,在较大位移区间内实现了具有良好线性度的测量,同时,根据实验结果测得灵敏度为2.13mV/μm,保证了测量的精准度.这种设计方法的使用扩大了塑料光纤的应用领域,同时,优化了传感器的精准度和线性化精度等性能指标.     

激光三角位移传感器误差补偿的建模研究

为降低激光三角位移传感器非线性误差对其测量精度的影响,研究了激光三角位移传感器误差补偿的建模方法。深入了解激光三角位移传感器工作原理,在此基础上定量分析该传感器非线性误差。利用神经网络构建激光三角位移传感器误差补偿模型,使用多层神经网络获取线阵CCD与接收透镜之间的夹角。以及入射光线与接收透镜之间的夹角的映射关系。运用所得映射实现激光三角位移传感器误差补偿。实验结果表明：激光三角位移传感器的重复性优良,且测量时的光斑在线阵CCD上的成像质量较为优异。该方法补偿后的激光三角位移传感器残差大幅度下降,最大下降幅度约为46%。将待测物体表面粗糙度控制在5.6μm～9.6μm范围内,可获得更好的激光三角位移传感器误差补偿效果。     

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.     

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.     

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.     

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