紫外LED照射器的控制系统设计

介绍了一种应用于紫外光固化领域的紫外LED照射器的总体结构及其工作原理,设计了紫外LED照射器的控制系统。该系统采用DSP+FPGA架构,DSP完成数据处理和系统控制功能;FPGA对DSP进行I/O口扩展以及完成一些辅助功能。照射器的最大紫外光照射功率达8 000 mW/cm2,可实现多种照射模式。此外,存储模块的引入可以方便用户设置及数据的掉电保存。相对于传统的固化设备,本次设计从仪器操作的便捷性以及功能的多样性进行了改进。     

光固化时间对白光LED光学性能影响

在贴片式白光LED封装中的荧光粉涂覆环节采用光固化的方法,研究UV固化时间对LED光学性能的影响。实验选取了九种固化时间,对封装出来的样品进行外观物理特性的观察测试并对完全固化的样品进行恒流老化和光度色度参数测试。结果表明:固化时间大于120 s时胶体基本固化;不同固化时间样品的峰值波长、色温、显色指数的最大值与最小值分别平均相差约1.2 nm、200 K、1.3个单位;固化时间大于210 s时,光通量的衰减率明显大于其他固化时间。该光固化胶在106.6 mW/cm2的紫外光功率密度下,固化120~180 s较为合适。从光学的角度探讨固化时间对LED性能的影响,对光固化技术在LED封装上的应用具有指导意义。     

彩色LED旋转显示屏的设计

为解决普通LED旋转屏显示色彩单一的缺陷,根据时间混色法利用单片机和三色LED设计了一种4 096色LED旋转屏。该旋转屏上的像素颜色编码为12 bit数据,通过4种亮度不同的帧的叠加,实现RGB每种颜色的16级灰度;利用在相邻两列LED显示间隙插入黑时隙的方法,降低了LED显示屏横向显示拖影等问题。经过实测验证表明,系统稳定、显示效果良好。     

曝光机对印制电路板阻焊层品质的影响

在印制电路板（PCB）阻焊层制作中，曝光环节尤为重要，不同颜色的阻焊油墨均会吸收紫外光，造成光固化，不同曝光机产生的紫外光波长不同，造成阻焊油墨光固化的程度也不同。以直接成像（DI）曝光机、卤素灯曝光机、发光二极管（LED）灯曝光机3种设备特性，对阻焊油墨性能的影响开展研究，以提高阻焊油墨与曝光设备的匹配性，提高阻焊品质和生产效率。经过测试，阻焊油墨与曝光机类别存在一定的适配关系，在适配情况下，阻焊油墨可提升光固化效果，提高阻焊品质和生产效率。     

DSM Desotech：紫外光固化光纤涂料领域中的领导者

DSMDesotech公司是为当今多个先进领域发展高性能紫外光（UV）固化材料的全球领先公司。在电信业,DSMDesotech是保护光纤、光缆产品的涂料、油墨和光纤带涂料等材料的世界领导供应商。     

DSM Desotech：紫外光固化光纤涂料领域中的领导者

DSM Desotech公司是为当今多个先进领域发展高性能紫外光（UV）固化材料的全球领先公司。在电信业,DSM Desotech是保护光纤、光缆产品的涂料、油墨和光纤带涂料等材料的世界领导供货商。     

DSM Desotech:紫外光固化光纤涂料领域中的领导者

DSM Desotech公司是为当今多个先进领域发展高性能紫外光（UV）固化材料的全球领先公司。在电信业,DSM Desotech是保护光纤、光缆产品的涂料、油墨和并带料等材料的世界领导供应商。     

LED阵列型紫外光固化光源系统

提出了一种适用于紫外光固化的新型光源系统.该系统以大功率紫外光LED和光学系统组成阵列结构来实现固化光源的高辐照度,大功率LED阵列由多路可控恒流源系统控制,根据固化材料的特点外部设定驱动电流,控制光源发光强度.与常用的高压汞灯相比,该系统无需高压驱动和冷却设备,具有操作简单、固化效率高和绿色无污染等优点.实验结果表明,该系统能够发出均匀稳定的高强度紫外光.     

DSM Desotech:紫外光固化光纤涂料领域中的领导者

DSM　Desotech公司是为当今多个先进领域发展高性能紫外光（UV）固化材料的全球领先公司。在电信业，DSM　Desotech是保护光纤、光缆产品的涂料、油墨和并带料等材料的世界领导供应商。     

DSM Desotech:紫外光固化光纤涂料领域中的领导者

DSM Desotech公司是为当今多个先进领域发展高性能紫外光（UV）固化材料的全球领先公司。在电信业，DSM Desotech是保护光纤、光缆产品的涂料、油墨和并带料等材料的世界领导供应商。     

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