时空混合控制式自由立体显示系统背光刷新方式优化研究

时空混合控制式自由立体显示是一种新型的自由立体显示技术,具有全分辨率和低串扰率优点,消除了背光源刷新与屏幕图像刷新不同步所导致的时域串扰率升高,这是时空混合控制式自由立体显示的关键问题之一。本文介绍了时空式立体显示系统的原理和动态背光的工作方式,提出了扫描式和垂直式两种不同的背光源刷新方式,着重对比了两种背光源刷新方式对屏幕亮度和串扰率的影响。通过实验测量给出了时空式自由立体显示系统背光源刷新的最优化参数设置。在优化配置条件下,系统串扰率低至2.64%,证明动态背光同步技术可以有效降低系统的时域串扰率。     

侧面发光光纤的制备原理及其应用

侧面发光光纤又称通体发光光纤、线型光纤、泄漏型光纤、大口径导光管甚至还被称为霓虹光纤等。它不仅能将光从光纤一端面传输至另一端面，而且还能将光从其包层表面泄漏出来，使光纤整体发光。本文介绍了侧面发光光纤的种类，简述了侧面发光光纤的制备原理及其方法。本文还叙述了侧面发光光纤的性能特征及其应用。     

自由立体显示器的光学性能测量与研究

为了评价自由立体显示器的光学性能,以八视点狭缝光栅自由立体显示器为例,针对不同的视点图像,测量了不同视角下的亮度值与色度值,研究自由立体显示器的光学性能,其光学性能包括自由立体显示器的最佳观看位置、串扰、可视范围、亮度均匀性、色度均匀性和莫尔条纹。结果表明,这种测量及分析方法实现了对多视点立体显示器光学性能的定量评估,增强了评估立体显示器性能的客观性,对自由立体显示器的设计具有指导意义。     

基于聚合物光纤局域网系统的自由空间光通信

设计了与125 Mbps聚合物光纤局域网兼容的自由空间光通信系统,以实现楼宇间的数据通信,克服聚合物光纤传输距离较短的缺点.自由空间光通信包括发射和接收两个部分,发射部分由650 nm半导体激光器,驱动电路和准直扩束镜组成,接收部分由接收透镜和光电探测器组成.半导体激光器的调制发射功率为3 dBm,光电探测器的探测灵敏度为-27 dBm.分析了大气对光信号的衰减以及大气湍流造成的光斑抖动对通信的影响,记录了系统的信号传输波形和通信眼图.实验表明,自由空间光通信可以延长聚合物光纤局域网的通信距离,使其在实际工程中的应用更加灵活.     

狭缝光栅自由立体显示器的立体图像串扰度

为了表征狭缝光栅自由立体显示器存在的左右眼视差图像的混叠程度,提出了立体图像串扰度C的概念。根据狭缝光栅自由立体显示器的结构和工作原理,应用几何光学知识,分析得出了立体图像串扰度C的计算公式,并给出了一个具体的狭缝光栅自由立体显示器的计算结果。通过观看实验,证明了所定义的立体图像串扰度C可以定量描述观看者在立体可视区域看到的立体图像的串扰程度。     

4/spl times/16 polymer fiber optical array couplers

A 4/spl times/16 plastic array coupler for power splitting in large-core polymer optical fibers is proposed and fabricated. Maximum coupling efficiencies of up to 84.7% and 91.4% were observed using, respectively, the total internal reflection type and metal coating type micromirrors formed along polymer fibers of 1.0-mm core diameter and 0.485 numerical aperture. The coupling uniformity for the two cases were 86% and 74%, respectively. The coupling efficiency and its relation to misalignments are studied.     

Field-emission display based on nonformed MIM-cathode array

We developed nonformed metal-insulator-metal (MIM) cathodes and demonstrated their suitability for field-emission displays (FEDs). The MIM cathodes have an emission current density of 5.8 mA/cm² at an operation voltage of 9 V. The cathodes are operated in the nonformed state, and they exhibit no fluctuation in the emission current, even without a ballast resistor. At a cathode-anode separation of 2 mm and an acceleration voltage of 4 kV, the divergence of the emitted electron beam is 25 μm. These features make nonformed MIM cathodes suitable for high-voltage acceleration-type FEDs. We also fabricated a prototype 3.8-cm diagonal frit-sealed color display, and demonstrated its matrix-multiplexing operation     

光开关选通的光纤激光水听器时分复用阵列

为了降低传感器系统的成本及体积,利用光纤激光传感单元的特性,采用光开关选通的光纤激光水听器时分复用技术,构建了实用的基于光开关的4元光纤激光水听器时分阵列。进行了理论分析和实验验证,分析了使用光开关选通的光纤激光水听器时分复用阵列方案的选通脉宽和损耗,指出了各通道光脉冲对干涉信号的采样率的限制因素。结果表明,光开关选通的光纤激光水听器时分阵列可以很好地完成复用信号的采集和复用,实验中4元时分复用水听器相邻通道的串扰为-17dB。     

光二极管线阵用于激光与光学显示——一种简单的光学多道显示仪

介绍光二极管线阵组成的简单光学多道分析系统的原理和性能,及其在激光与光学显示上的应用。     

聚合物光纤用氟树脂(续前)

2.2　 THV氟塑料THV最初是由德国 Hoechst(赫思特 )公司于2 0世纪 80年代初开发的 ,其原商品名为Hostaflon TMTFB.X,1 993年 ,Hoechst公司将该技术和市场转让给美国 3M公司 ,其商品名改为 3MTMTHV,1 996年美国 3M公司和 Hoechst公司于 1 996年合资组成 Dyneon公司 ,因而该产品现称为 Dy-neon TMTHV。THV系列氟塑料主要是由四氟乙烯( TFE)、六氟丙烯 ( HFD)和偏氟乙烯 ( VDF)等采用乳液共聚法制备成的 [7] ,THV就是以这三种单体的第一个英文字母命名的。THV氟塑料同常规氟塑料有以下不同之处 :1 )它可熔融加工 ,加工温度…     

聚合物光纤用氟树脂

分析了聚合物光纤对氟树脂的要求，详细介绍了七种氟树脂的性能及其加工工艺，这些氟树脂包括Teflon AF,THV,FEP氟化丙烯酸树脂，Cytop,F24 ,氟化聚碳酸酯。     

紧凑型增强现实头盔显示器光学系统设计

设计了一种用于增强现实的紧凑型头盔显示器光学系统,该系统视场角26.3°×19.7°,焦距32 mm,出瞳距离20 mm,出瞳直径8 mm。在光学系统中使用衍射面与高次非球面设计,实现了光学系统的轻量化,系统内、外两个光通道的光能量利用率分别为1／4和1／2,光学系统镜头直径小于45 mm,重量小于8 g,不仅在结构上满足使用者头戴要求,而且成像质量接近衍射极限,最大场曲和最大像散分别为45μm和46μm,畸变小于5％,最大垂轴色差值仅为6.9μm,满足增强现实“虚实结合”显示需求。     

满足夜视兼容显示应用的三基色LED背光配色方法

三基色LED背光存在两个独立的配色自由度,约束条件为夜视辐亮度不超标及与参考点之间色坐标偏差最小,在这两个约束条件下存在唯一最优的配色方案。本文通过二元线性回归方法,得到色坐标和辐亮度之间的近似依赖关系,并给出通过最少三次试配色获得的辐亮度测量结果推出最佳色坐标配置的计算方法。通过对多于三次测量数据残差的分析,表明在基本测量精度和样本点选取范围内,辐亮度估计的偏差可以控制在2%以内。     

Near hexagonal close-packed optical fiber array for parallel optical interconnection

In conventional optical fiber based two-dimensional (2-D) parallel optical interconnection (POI), optical fiber arrays are aligned to 2-D light sources and detectors using precisely fabricated hole-plate or stacked V-groove plates. All these structures have problems in making positioning components and assembly with high accuracy. For polymer optical fibers with large diameter, the whole dimension of the array will be too large if they are positioned using V-grooves or hole-plate. This paper proposes a 2-D near hexagonal close-packed (NHCP) optical fiber array for 2-D POI. NHCP array has a cross-sectional profile of near-hexagonal lattice and with fibers precisely positioned at each node of lattice. Compared with perfect HCP lattice, NHCP lattice is slightly stretched in one dimension and still have all fibers with nonuniform diameter packed tightly with high packing fraction. The position of fibers in NHCP array is very important when aligned to 2-D light sources and detectors. This paper deduce the analytically expression for the probability distribution of fiber position which is related to variance of fiber diameter and structure parameters of NHCP array, and verified it by computer simulation. Experiment samples of NHCP array have been made showing that NHCP array is easy to be fabricated.     

基于半导体光放大器的可扩展型光开关矩阵

未来的高速和高度灵活的光分组交换网络要求开关速度达到纳秒量级且集成度高的大规模空间光开关矩阵。在分析了基于半导体光放大器的常用结构形式的光开关矩阵存在规模局限性的基础上,综述了新型的可实现大规模集成的基于半导体光放大器的光开关矩阵的基本原理和研究现状。     

Code reusuable optical CDMA system using an array of superstructured fiber Bragg gratings

We have proposed a user extensible optical CDMA system which employs a repeated use of codes in the encoders and the decoders. In this study, we report the user-extension effect by using an array of superstructured fiber Bragg grating (SSFBG) as an encoder and a decoder through the simulations and the experiments. We performed the experiments by using 4 SSFBGs in each encoder and decoder. We have shown that the capable number of users can be increased up to ₆₃C₁?₆₃C₁?₆₃P₂ when 63 orthogonal codes are used.     

Compact modal interferometer built with tapered microstructured optical fiber

A modal interferometer was built with tapered large-mode-area microstructured optical fiber (MOF). The tapering was introduced by slowly stretching the fiber while it was heated with a high temperature flame torch. With this "slow-and-hot" tapering process, the MOF air holes collapse and the taper waist is transformed into a solid unclad multimode fiber. This allows the coupling between the fundamental HE/sub 11/ MOF mode and the HE/sub 1m/ modes of the solid fiber. The beating of the HE/sub 1m/ modes makes the transmission spectra of the taper to exhibit an oscillatory pattern. The influence of the taper geometry and wavelength on the interference pattern is discussed. The interferometer can be used for diverse applications.     

POF在局域网中的应用

综合比较了各种局域网接入方式，介绍了国内外近期有关聚合物光纤局域网的研究成果。认为聚合物光纤在短距离光通信中具有成本与技术优势，特别在局域网与光纤入户中的应用潜力巨大。     

Thermally stable high-bandwidth graded-index polymer optical fiber

High-bandwidth poly (methyl methacrylate) PMMA base graded-index polymer optical fiber (GI POF) with high thermal stability is proposed. No distortion of bandwidth was observed even after more than 10000 hours aging at 85°C by selecting the large sized aromatic dopant which has a stable secondary interaction with PMMA matrix and maintains the high glass transition temperature (Tg) of the core of GI POF. The relationship between the heat-drawing condition from the GI preform to the fiber and the thermal stability in the attenuation was investigated. It was clarified that the length shrinkage of the fiber during the aging at high temperature caused large attenuation increase. On the other hand, the degree of shrinkage could be tightly controlled by changing the heat-drawing tension. It was confirmed that the GI POF drawn with optimized heat-drawing tension had no shrinkage of the fiber during aging at 70°C and no attenuation increase was observed     

渐变折射率塑料光纤的研究动态

介绍了渐变折射率塑料光纤 (GI- POF)的传输性能、制造方法和应用 ,简述了国内GI- POF的研究动态和展望。