压电微流量阀驱动电源的研究

研究了一种低纹波输出的压电陶瓷驱动电源,实现对压电驱动微流量阀的输出微流量的控制.利用单片机控制数字频率合成芯片来产生各种函数信号,研究了高低压稳压电路、小信号放大处理及功率放大电路,控制信号经滤波、放大及稳压等处理后,函数信号形成高压输出,驱动压电陶瓷,对微流量阀阀芯位移进行驱动,从而实现对微流量阀输出微流量的精密控制.通过对该电源输出特性的试验研究,结果表明,该电源具有良好的输入输出线性特性及低纹波特性,其线性度拟合相对误差仅为84 mV,高压输出纹波电压低于10 mV,这对提高微流量阀输出微流量的控制精度具有重要意义.     

一种压电陶瓷微位移器驱动电源研究

在研究压电陶瓷微位移器的基础上,针对压电陶瓷的驱动特点和要求,设计了一种驱动电源。以单片机Atmega128和高压运算放大器PA78为核心器件,以及相关电路构成电压控制型驱动电源。介绍了主要模块电路的功能和实现,并对驱动电源进行测试实验。驱动电源可输出0~300 V连续电压,分辨率可达10 mV、静态纹波＜5 mV。结果表明该电源具有线性度高、稳定性好、分辨率高等优点。     

一种高压压电陶瓷驱动电源的设计

为了满足压电陶瓷在振动平台微位移测试系统中输出更大范围的微位移及保持更高精度的条件,设计了一种高压大电流、带有直流偏置可连续调频调幅的正弦波输出压电陶瓷驱动电源。该文介绍了该驱动电源的设计方案、关键电路设计、控制系统软件设计及实验测试。该驱动电源以全桥逆变电路、隔离直流-直流抬压电路为核心,采用电压、电流双闭环比例-积分控制正弦脉宽调制(SPWM)波的基波来调节输出电压。通过搭建实验平台,验证了当压电陶瓷电容为5μF时,该驱动电源能实现在5 Hz～1 kHz频响内电压100倍增益放大,输出0～1 000 V的动态正弦电压,最大输出功率达到7 kW。结果表明,设计的压电陶瓷驱动电源具有输出电压高,输出功率大,频率响应快,且减小了电源整机体积和质量。     

压电微位移致动器的研制及其应用

文章是以光纤光栅传感系统中匹配FBG光纤解调为背景展开研究的,对压电陶瓷的材料特性、压电陶瓷驱动电源的软硬件设计和压电微位移致动在匹配FBG光纤解调中的应用等问题进行了探讨,开发了实用的压电微位移致动器。针对压电陶瓷的容性负载特性,提出了驱动电源的设计方案,完成了驱动电源软硬件设计,构建了直流稳压电路、PA78组成的混合放大电路。实验表明,所研制的压电微位移致动器具有良好性能,可应用于光纤光栅传感系统的匹配FBG光纤解调中。     

负载刚度对压电元件输出特性影响的研究

压电元件在驱动微操作系统时,其输出位移要小于空载状态下的输出位移,针对众多引起压电元件输出位移减小的原因,重点分析了压电陶瓷输出位移与负载刚度之间的关系,并进行了压电陶瓷驱动弹性负载的实验。实验结果表明,压电元件的输出位移随着负载刚度的增加而减少。此结果为设计微操作系统时选用压电元件提供了理论依据。     

一种大容性负载的压电陶瓷驱动电源设计

压电陶瓷作为微定位系统的动能器件,可达到纳米级的位移精度。针对位移驱动型压电陶瓷的大容性负载特点,基于PA92设计了一种高精度、大电流的动态驱动电源。通过电容超前反馈、隔离电阻结合反馈及相位补偿等方式提高了电源的稳定性。分析结果表明,该电源能有效应用于纳米级定位系统中,在大容性负载时具有良好的动态性能,输出电压精度可达0.5 mV。     

高精度大功率压电陶瓷驱动关键技术

压电陶瓷驱动电源是压电陶瓷微位移系统中的关键部件。以高压功率放大器PA93为核心,提出了一种新型高精度、大功率压电陶瓷驱动电源,适合驱动大行程、大推力压电陶瓷致动器。重点阐述了电路的设计方案,对复合放大电路进行了特性分析。实验结果表明,该驱动电源具有精度高,输出电压高,电流大,稳定性好的特点。当驱动等效负载电容为24 μF的压电陶瓷时,在0~100 Hz频率范围内实现了0~10 V信号到0~100 V信号的动态放大,输出电压精度优于3×10-5,最大输出电流350 mA。     

基于自适应逆控制的压电驱动电源

为了减少压电驱动器迟滞非线性,提高微系统的定位精度,该文设计了基于自适应逆控制的压电驱动电源。选用型号TMSF320F28335的数字信号处理(DSP)芯片,对信号调节器、前级DC-DC的Boost升压电路和后级DC-AC的单相全桥逆变电路进行设计分析。在CCS6.0软件开发环境下进行编程,实现了SPWM驱动信号的生成、对位移信号进行AD采样和Prandtl-Ishlinskii自适应逆模型的功能。为了验证所设计的压电驱动电源的自适应控制性能,采用压电陶瓷驱动器开展了基于自适应逆的驱动控制实验。结果表明,在不采用控制的条件下,1 Hz时压电陶瓷驱动器的输出位移均方根误差(RMSE)为3.239 5μm,绝对值平均误差(MAE)为2.985 1μm;随着频率的增加,20 Hz时RMSE、MAE的最大值分别为21.402 9μm、19.306 2μm。使用基于自适应逆控制的压电驱动电源,1 Hz时RMSE为0.324 9μm, MAE为0.265 6μm; 20 Hz时压电陶瓷驱动器的输出位移RMSE为12.639μm, MAE为11.956 1μm。     

基于PA85的新型压电陶瓷驱动电源

压电陶瓷驱动电源是压电陶瓷微位移器应用中关键部件.PA85是一种高压、高精度的MOSFET运算放大器.文章介绍了一种基于PA85的新型压电陶瓷驱动电源,详细介绍了电源复合放大电路部分的设计原理和并对其稳定性进行了分析.该电源具有精度高,驱动能力强,结构简单,稳定性好的特点.     

基于PA85的新型压电陶瓷驱动电源

压电陶瓷驱动电源是压电陶瓷微位移器应用中关键部件。PA85是一种高压、高精度的MOSFET运算放大器。文章介绍了一种基于PA85的新型压电陶瓷驱动电源，详细介绍了电源复合放大电路部分的设计原理和并对其稳定性进行了分析。该电源具有精度高，驱动能力强，结构简单，稳定性好的特点。     

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.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

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.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.