基于光线追迹的LED裸眼三维显示技术准直性研究

在LED集成成像裸眼三维显示中,LED大屏幕的单个像素点的发散角很大,使用平凸及双凸透镜,图像的重构光线发散且相邻透镜单元间的像素串扰大,导致立体场景再现的过程中图像不清晰,影响重构三维图像的质量。根据光线追迹原理,分析了LED集成成像的成像过程,研究不同形状透镜阵列与LED集成成像相邻透镜单元间像素点间串扰的关系,仅使用单个凹凸透镜有效地控制了重构光线的发散问题,使通过透镜的重构光线更加汇聚准直,光线平行出射,有效地减小了相邻透镜间的像素串扰,提高了成像质量。通过比较字母模型成像的仿真结果,凹凸透镜非常适用于LED集成成像,成像的效果优于其他形状透镜。     

微透镜阵列扫描成像系统的衍射分析与研究

微透镜阵列是微光学元件典型器件之一,广泛的应用于光束整形、精密测量、光学成像等场景。本文研究了微透镜阵列扫描成像系统的工作机理,并重点分析了影响成像质量的光场衍射效应和杂散光串扰,完成了微透镜阵列扫描成像系统衍射效应的推导与仿真,揭示了衍射效应与焦距及子单元孔径之间的关系,为微透镜阵列扫描成像系统的实际应用提供了导向,并为微透镜阵列的光束控制应用提供理论支撑,为微透镜阵列的建模、设计等提供依据。     

立体视区完整的无串扰集成成像3D显示

集成成像三维（3D）显示技术具有连续视点、无需助视设备等特点，但普遍存在的视觉串扰现象严重影响立体观看效果。分析图像元在立体视区成像的有效像素区域，推导出图像元上的串扰图像区域分布的变化规律，提出一种立体视区完整的无串扰集成成像3D显示结构。精确设计具有渐变孔径的掩模板阵列，其既能完全透过有效像素光线，使光线向主视区和各阶立体视区成像，保留了集成成像立体视区分布的完整性，又能阻挡串扰像素光线的出射，消除了相邻视区间的串扰，实现了立体视区完整的无串扰集成成像3D显示。提出的结构简单易于实现，有助于集成成像显示技术的进一步推广。     

基于3DS MAX的集成成像研究

集成成像(II)是一种利用二维微透镜阵列进行三维信息的记录和重现的技术.介绍了集成成像技术的基本原理及其优缺点,提出了一种基于三维设计和动画制作软件3DsMAX的II技术,利用3DS MAX来实现II的三维信息的记录,利用显示器和菲涅尔微透镜阵列组成的实验装置实现II的三维信息的重现,解决了常规II技术存在的空间反转和串扰问题,从而研制出基于Il技术的原理性裸眼三维显示器.     

液晶微透镜阵列直接成像

针对传统显微镜结构复杂且视场角小等问题，提出一种两路低电压驱动的液晶微透镜阵列结构，透镜的焦距由3个电极控制，中间电极为圆孔阵列图案电极，作为孔径光阑以阻止微透镜外的杂散光。对该阵列的波前和光焦度进行了测试，搭建了一套简易液晶微透镜阵列直接成像系统，每个微透镜都对待观察物体的不同区域成像，通过近平行光照明减小相邻微透镜间的串扰，拼接所有单元图像得到完整图像。该系统无需额外的光学器件，结构简单紧凑。液晶微透镜阵列具有大视场，成像区域具备可扩展性，为实现大视场下的简易显微成像提供了新思路。     

光学胶膜液体可变焦微透镜阵列

微透镜阵列在光束匀化、波前测量、集成成像等领域有广泛应用。设计了一种基于光学胶膜(Optically Clear Adhesive, OCA)的液体可变焦微透镜阵列。采用矩形排列的硅微孔阵列控制单个透镜的孔径和排布,并以OCA光学胶膜和去离子水作为微透镜阵列的塑形材料。通过调整微流体腔内液体注入的体积实现对透镜焦距从1.46~10.44 mm的调整。依据聚焦与成像实验证实了微透镜阵列具有良好的均匀性。最后,将该微透镜阵列应用于激光光束匀化整形,通过一对微透镜阵列实现了光束匀化整形。进一步通过固定一对微透镜阵列的间距实现匀化光斑尺寸在7.2~8.4 mm内可调,为匀化光斑尺寸可调提供了新思路。     

高填充因子微透镜阵列的快速制备及特性分析

微透镜阵列是一种被广泛应用于光信息处理、光传感、光计算、光通信和高灵敏度成像等领域的精密光学元器件之一。通过一些先进的制造技术已经可以制造出不同几何形状、轮廓和光学特性的微透镜阵列。然而,由于三维微制造工艺的难度,使得高填充因子微透镜阵列中的微透镜很难实现紧密排列。提出了一种快速、低成本的微流体操纵技术,用于制备高填充因子微透镜阵列,且对其制备工艺进行了初步的演示。这种易于操作的制造技术适用于微透镜阵列的大批量生产,极大地提高了生产效率。通过预先制备出的三种不同尺寸(微柱直径分别为300、500、700 μm)的微柱,实现了与其对应不同形状和尺寸的微透镜阵列的制备,并搭建了一套光学成像系统以对这些微透镜阵列进行成像性能的评估。主要对微透镜阵列的焦距、成像精度和每个微透镜阵列中各个微透镜子单元成像的均一性进行测试,利用所提出的微流体操控技术制备的微透镜阵列具有良好的成像性能,有望能够被应用到三维成像、光均匀化等诸多应用中。     

基于微透镜阵列光束均匀化的傅里叶分析

为了提高高功率固体激光器泵浦光束的均匀性,分析了成像型和衍射型微透镜阵列匀化光束的基本原理,基于菲涅尔衍射和傅里叶变换公式,推导出了微透镜阵列焦平面上光强分布的解析表达式,比较了两种光束微透镜阵列对光束匀化的效果。同时,研究了成像型微透镜阵列子透镜的相对孔径及微透镜阵列间距对光强分布的影响。结果表明,成像型微透镜阵列具有更好地匀化效果,且子透镜孔径是影响光束均匀性最主要的因素。     

基于不同微透镜阵列参数的集成成像微图像

提出一种基于不同微透镜阵列参数的集成成像微图像阵列生成方法。在该方法的拍摄过程中, 首先通过微透镜阵列1拍摄三维场景获得微图像阵列1, 再通过一个包括虚拟显示和虚拟拍摄两个步骤的像素映射算法, 生成与微图像阵列1参数不同的微图像阵列2。在显示过程中使用的微透镜阵列2与拍摄时的微透镜阵列1具有不同的参数, 微图像阵列2通过微透镜阵列2重建出全真的3D图像, 重建的3D图像没有图像缩放和畸变。同时本文还推导了微图像阵列1、2和微透镜阵列1、2各参数应满足的数学关系。实验结果验证了理论推导的正确性。     

基于不同微透镜阵列参数的集成成像微图像阵列生成方法

提出一种基于不同微透镜阵列参数的集成成像微图像阵列生成方法。在该方法的拍摄过程中,首先通过微透镜阵列1拍摄三维场景获得微图像阵列1,再通过一个包括虚拟显示和虚拟拍摄两个步骤的像素映射算法,生成与微图像阵列1参数不同的微图像阵列2。在显示过程中使用的微透镜阵列2与拍摄时的微透镜阵列1具有不同的参数,微图像阵列2通过微透镜阵列2重建出全真的3D图像,重建的3D图像没有图像缩放和畸变。同时本文还推导了微图像阵列1、2和微透镜阵列1、2各参数应满足的数学关系。实验结果验证了理论推导的正确性。     

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.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

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.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

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.