扩展差动共焦显微系统量程范围的方法与措施

为扩展差动共焦显微镜(HCMS)的测量量程范围,使其满足三维微细结构和三维表面轮廓测量时的需求,基于环形光瞳滤波技术提出一种扩展HCMS测量范围的环形光瞳量程扩展方法与技术。该方法应用二元光学整形原理将HCMS中两探测器探测到的光强响应曲线的半高宽拓宽,继而达到扩展量程范围的目的。与常用的通过减小共焦显微系统物镜的数值孔来扩展量程范围的方法相比,整形环形光瞳量程扩展法在扩展量程范围的同时,还改善了HCMS的分辨特性,压缩其旁瓣,避免了因减小物镜数值孔径值引起的横向分辨力降低的不足。理论分析和实验表明：当环形光内、外径半径比ε=0．5时,环形光瞳量程扩展技术使HCMS的量程扩展了1倍,同时使其横向分辨力得到改善,旁瓣得到抑制。     

可旁向测量的共焦式激光测头

本文在研究了共焦式测量原理的基础上 ,研制出一种含参考光路的可旁向测量的共焦式新型激光测头。这种测头舍弃了共焦式测头中的微型位移传感器 ,简化了系统结构 ,降低了成本。文中论述了其测量原理及结构 ,给出了测量系统的动态特性的实验结果。结果表明激光测头的测量分辨力为 0 .2 μm ,动态特性为 336点 /秒 ,测量范围为± 0 .1mm。     

光网络中保护光路的快速激活信令机制

针对通过用多协议标签交换(GMPLS)光网络中工作光路出现故障时保护光路的激活过程可能导致较长的故障恢复时间,成为限制应用的一个关键因素.本文从信令机制的角度研究缩短故障恢复时间的方法,扩展了现有的GMPSL信令协议,提出了一种保护光路的快速双向激活信令机制,分别从首尾两个方向同时激活一条保护光路,从而缩短了故障恢复时...     

DiffServ-aware OBGP——一种新的域间端到端光路创建机制

OBGP是一种分布式协议,通过在多域光网络中传递路由和信令信息,使网络边缘的客户能够建立,管理和控制自己的光路。通过扩展OBGP,提出了一种新的DiffServ—aware OBGP机制来解决目前仍然存在的一些问题,比如域的接入控制以及通过对客户请求进行区分来解决资源请求竞争问题。文章定义了对目前OBGP消息的基本扩展,以及在光路建立过程中提供区分服务所需要的其他扩展,并且详细描述了在该机制下的光路创建过程。仿真证明了新机制不仅能够根据客户请求较好地创建端到端的光路,同时在资源竞争的情况下高优先级别的客户有更高的成功率来创建所需的光路。     

具有高空间分辨力的双极性绝对式差动共焦检测方法

提出一种用于超精密三维微细结构测量的横向光学超分辨、轴向纳米级分辨的绝对式高空间分辨力共焦检测方法,该方法利用超分辨光瞳滤波技术最大程度地改善共焦显微系统的横向分辨力,利用探测器轴向偏置的双探测共焦光路布置和双探测信号归一化差动接受最大程度地改善共焦显微系统的轴向分辨力,最终实现共焦检测系统的高空间分辨力双极性绝对测量.文中以整形环形光横向超分辨为例,初步验证了提出的高空间分辨力差动共焦扫描检测方法的有效性.实验表明:当入射激光束波长λ=632.8nm,测量物镜数值孔径取NA=0.85,ε=0.5,μM=6.95时,整形环形光瞳式差动共焦传感器的横向分辨力优于0.2μm,轴向分辨力优于2nm.     

基于相位补偿的调频连续波大长度测距中的色散校正

基于调频连续波测距的原理搭建并改进了双光路调频连续波测距系统,在测量光路增加光纤延迟线使测量距离拓展到了65 m.还研究了等光频重采样中色散的影响,推导出了带有色散和光纤延迟线的重采样模型,提出了在调频连续波大长度测距中通过频率幅度来调节相位补偿系数的色散校正方法.实验表明,在45~65 m的范围内增加了光纤延迟线并且有效的校正了色散,校正色散后在65. 165 m处测距值与干涉仪测量值最大误差小于500μm,标准差为246μm,频谱分辨力高达123μm,十分接近理论分辨力.文章的研究为调频连续波大尺寸测量提供了可行性的参考.     

基于Web服务的光路封装及其提前预留管理模型

目前,很多高性能光网络平台能为网格计算环境动态提供按需专用光路,以满足e-Science等上层应用的数据密集性需求.为了更有效共享和管理光网络的光路资源,提出了一个基于Web服务的光路封装及其提前预留管理模型.详细描述了其运作机制和软件模块构成,并扩展语义Web中资源描述框架(RDF)来描述光网络中的光路资源.这有助于将光路资源以有状态Web服务形式发布并调用,及应用Web技术自动完成光路资源信息更新和管理.     

向50nm拓进的光学光刻技术

非光学下一代光刻技术的缓慢进展和国际半导体技术发展规划 (ITRS)的加速 ,使光学光刻肩负着IC产业的重任 ,进一步向亚波长图形领域进军。为此 ,人们开发了大量的光学光刻扩展技术。其中包括传统的缩短波长和增大数值孔径 ,以及为了扩展最小间距线间图形的分辨力而提高部分相干性。通过这些途径 ,在 1 93nm曝光中实现了 >0 .80的数值孔径和0 .85的部分相干性 ,并将进一步向 1 57nm乃止 1 2 6nm过渡。此间 ,离轴照明 (OAI)、移相掩模(PSM)和光学邻近效应校正 (OPC)等K1因子将作为分辨力提高技术的核心 ,补充到光学光刻技术范畴。此外 ,光学光刻的扩展还将通过像场尺寸缩小和倍率增大的方法使步进扫描光刻机更好地支持并可望进入至少 70nm的技术节点 ,乃至 50nm的下一代光刻。     

调制边缝位相的全息三缝干涉仪

本文介绍了调制一条边缝光路位相的全息三缝干涉仪。其量程比调制中缝位相的三缝干涉仪扩大一倍,并能对大范围的连续光程变化进行测量。     

新型交流数字电压表设计

设计一种基于AT89C51单片机的量程自动转换的数字电压表,以AT89C51,AD574为核心器件,采用运算放大器和集成多路模拟开关电路设计了电压表量程自动切换技术,构成完备的测量系统.可以对0～500 V电压范围的电压进行量程自动转换的精确测量.该设计具有体积小,驱动电流小,动作快,结构简单,操作方便的优点,可用于实验教学中.     

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。     

A Fully Differential Rail-to-Rail CMOS Capacitance Sensor With Floating-Gate Trimming for Mismatch Compensation

This paper presents a fully differential capacitance sensor employing the CBCM technique to map differential input capacitances into rail-to-rail differential output voltages. The circuit has been designed for measuring capacitances in the $pm hbox{25-fF}$ range, appropriate for sensing live cells using on-chip microelectrodes. An array architecture based on a shielded current routing bus has been developed for incorporating the capacitance measurement circuit into sensor arrays, with each pixel comprising four minimum-size digital transistors, enabling high-density integration. In addition to improving spatial resolution, the shielded current bus also eliminates the need for individual pixel calibration, conserves sensor evaluation speed, and provides protection from junction leakage. The sensor employs a 3-phase clocking scheme that enables on-chip gain tuning. The paper also presents a modified version of the sensor circuit incorporating floating-gate transistors for mismatch compensation and output offset cancellation, performed using a combination of impact-ionized channel hot electron injection and Fowler–Nordheim tunneling mechanisms. Chips comprising both versions of the sensor circuits in test arrays employing the shielded current routing bus were fabricated in a commercially available 2-poly, 3-metal, 0.5-$mu{hbox {m}}$ CMOS process. The sensor operation was demonstrated by measuring on-chip test capacitances comprising single and interdigitated metal electrodes, configured using different capacitance compensation schemes. The differential sensor in combination with the shielded current bus exhibits a maximum sensitivity of 200 mV/fF, a resolution of 15 aF, and an output dynamic range of 65 dB.      

A network for large numbers of interferometric sensors and fiberBragg gratings with high resolution and extended range

We describe an active form of a frequency division matrix array network developed to support both interferometric sensors and fiber Bragg gratings to demodulate both quasistatic and periodic measurands. Novel telemetry allows an improved measurement range using a single source and uses a fundamental interferometric principle for self-calibration. High resolution is achieved through active but remote demodulation of passive sensors. A resolution of 0.019 nm with a measurement range of 62.8 μm for an interferometric sensor and a strain resolution of 0.19 με with a measurement range of 6.28 mε was obtained for fiber Bragg grating sensors     

Low-Cost IR Reflective Sensors for Submicrolevel Position Measurement and Control

This paper investigates the feasibility of using commercially available, low-cost IR reflective sensors for micro- to submicroscale position measurement and control. These sensors are typically used as optical switches; however, their application for detecting fine motion, such as the movement of a piezoactuator, has not been investigated. Five IR sensors were evaluated to determine their range, resolution, linear distortion, noise characteristics, and bandwidth. Experimental results show that the performance of the IR sensors compares well with a commercial inductive sensor that costs significantly more. For example, the measured resolution was within several hundred nanometers over a $pm 200$  $mu$m range and the linear distortion was significantly lower than the inductive sensor. A selected IR sensor was used in the design of a state-feedback control system to compensate for hysteresis and creep in an experimental piezopositioner. Compared to the open-loop system, by using the IR sensor in feedback, the output hysteresis was reduced by over 95%. These results show the potential of such sensors in the design of low-cost microprecision mechatronic positioning systems.      

Smart CMOS Image Sensor With High SBR and Subpixel Resolution for Light-Section-Based Range Finding

Light-section (LS)-based range finders are commonly used for obstacle recognition in home service robots and autonomous vehicles. This paper proposes a smart CMOS image sensor for LS-based range finding. The proposed sensor can detect the laser light, even under very strong ambient-illumination levels by using a multiple-capture frame-correlated double sampling (F-CDS), which is realized with an inverter-based switched-capacitor F-CDS accumulator. The proposed sensor also includes on-chip winner-take-all circuits that significantly reduce the software and hardware complexity of interpolation for the subpixel resolution. The prototype chip was fabricated using a 0.35-mum CMOS process. The measurement results show that the proposed sensor can detect a laser line with an intensity that is 56.5 dB lower than that of the ambient illumination, providing a spatial resolution of plusmn0.16 pixels.     

1400万像素CMOS传感器高速读出及信号采集的研究

面阵图像传感器的读出电路和信号采集电路是影响图像信号性能的关键部分之一。文章介绍了采用2路双通道AD及USB2．0实现了1400万像素高分辨率CMOS面阵传感器的大动态范围,低读出噪音的高速信号采集系统,并对系统的传输速度、分辨率、图像噪音、光强测量稳定性、近红外响应等进行了实验研究。     

HeNe激光双折射外腔回馈位移测量仪研究

基于单模激光器的双折射外腔回馈位移测量系统能输出两路回馈条纹信号,且条纹相位差不受回馈外腔长的影响,因此在研制大量程、高分辨位移测量系统方面极具潜力。开展了双折射外腔回馈的相关现象研究,研制了性能优良的位移测量仪器。稳频和回馈外腔扫描技术相结合,进一步提高了系统的频率稳定度（优于10-7）和抗干扰性能力。试验对系统进行了零漂、拍频和比对测试,其量程超过200 mm,分辨率为15.82 nm,线性度优于2.310-7。分析了系统的主要误差来源,估算了总的测量误差为0.21 m。回馈位移测量仪具有结构简单、分辨率高、线性度好以及测量范围大的优点,工业应用前景广阔。     

Ozone measurement in visible region: an optical fibre sensor system

Ozone measurement based on the optical absorption of visible light at 603 nm using polymer optical fibres is investigated and tested. Comparisons with a commercial UV based sensor demonstrate the ability of the visible based sensor to measure high concentrations over a range 27-127 mg/litre. A resolution of 5 mg/litre is also demonstrated for this sensor.     

用于复杂轮廓表面数字化光纤测量系统（Ⅰ）：关键技术

本文详细论述了用于复杂轮廓表面测量的光纤传感器系统,给出了关键技术的具体实现方法。实验结果验证了方法设计的正确和有效：激光器光功率输出的稳定性好于0．07％,横向分辨力为8μm,测量范围可达6mm。     

Optical fiber pressure sensor based on photoelasticity and itsapplication

An optical fiber pressure sensor based on the photoelastic effect using a novel compensation technique is described. Two optical sources and a polarization-splitting prism are incorporated into a sensor system to minimize output drifts. The four major factors-the optical source power, the fiber loss, the optical coupling loss, and the modal power distribution in fibers-are well compensated. The measurement range of 0-147 kPa has been obtained with accuracies of 0.2% within the temperature range of -10°C to 42°C and a resolution of 10 Pa has been achieved. Compensation for fiber loss has been observed up to -30 dB. This sensor system has been successfully put into practical operation for oil storage measurement in a tank