LED显示屏光安全及标准化研究

论述了LED显示屏光安全以及干扰光的基本概念,分析了LED显示屏干扰光的成因,对LED显示屏干扰光的标准化工作进行了探讨和研究,并提出LED屏干扰光标准化研究的技术难点,对LED显示屏设计、安装和使用具有一定的现实意义和指导意义.     

Special problems in applying the physical optics method forbackscatter computations of complicated objects

The backscatter computation of complicated objects is carried by the physical optics (PO) method, known as the vector Kirchoff approximation. The object is described by a geometrical model using flat plates (panels). These panels can be nonperfectly conducting and multilayered. The PO solution for the scattering matrix of a single multilayered panel is evaluated in detail using the Fresnel reflection coefficients. An example of the computed reflection coefficient of a two-layered medium is presented. The phase integral of the PO method is solved analytically. The hidden-surface problem is discussed, and the procedure for the treatment of doubly reflecting panels is described. For an ideal conducting cube with additional surfaces that generate shadow and double-reflection effects, the computed radar cross section (RCS) is compared with measurements. Computational results of the RCS for nonperfectly conducting panels are given     

Recent developments in three-color plasma display panels

This paper describes recent developments in the fabrication of three-color-phosphor plasma display panels that improve both electrical and optical performance. The electro-optical characteristics of panels incorporating a phosphor bar pattern are presented, including the properties of panels fabricated with a black, UV-absorbing material surrounding the phosphors. In addition, processes developed to produce 20 × 20 in plasma panels with 512 × 512 three-color resolution elements at a total line density of 60 per inch are described.     

场致发光电源电路

详细分析了场致发光器件两种电路的各种结构形式和工作特性，这些电路能耗小、光效高，适用于场致发光显示和液晶显示的背光源。     

Printable,Transparent, and Flexible Touch Panels Working in Sunlight and Moist Environments

The ongoing revolution of touch‐based user interfaces sets new requirements for touch panel technologies, including the need to operate in a wide range of environments. Such touch panels need to endure moisture and sunlight. Moreover, they often need to be curved or flexible. Thus, there is a need for new technologies suitable, for example, for home appliances used in the kitchen or the bathroom, automotive applications, and e‐paper. In this work, the development of transparent and flexible touch panels for moist environments is reported. A piezoelectric polymer, poly(vinylidene difluoride) (PVDF), is used as a functional substrate material. Transparent electrodes are fabricated on both sides of a PVDF film using a graphene‐based ink and spray coating. The excellent performance of the touch panels is demonstrated in moist and underwater conditions. Also, the transparent device shows very small pyroelectric response to radiative heating in comparison to a non‐transparent device. Solution processable electrode materials in combination with functional substrates allow the low‐cost and high‐throughput manufacturing of touch panels using printing technologies.     

Solar thermoelectric generator for near-earth space applications

The theory, design, fabrication, and testing of flat plate thermoelectric generator panels for near-earth orbits are described. These panels are capable of producing 3 watts/ft²and 15 watts/pound when operating in a near-earth orbit. The potential advantages of these solar energy converters, as compared to photovoltaic cells, are discussed and include higher radiation resistance, improved watts/pound, and lower cost on a per-watt basis.     

Minimum-Error Splitting Algorithm for a Dual Layer LCD Display—Part II: Implementation and Results

A dual layer liquid crystal display (LCD) is able to achieve a high dynamic range by stacking two liquid crystal panels one on top of the other over an enhanced backlight unit. However, the finite distance between the two panels inevitably introduces a parallax error when the display is observed off-axis, and the dynamic range limitations of the individual panels introduce a reconstruction error near sharp edges in the input image. In Part I, we have formulated the image splitting as a constrained optimization problem in which a joint minimization of the parallax error and the visibility of the reconstruction error is performed.      

LED显示屏质量提升的探讨

近年来LED显示屏被广泛应用于室内外显示领域。文章主要依据信息产业部标准SJ/T11141-2003《LED显示屏通用规范》和SJ/T11281-2007《发光二极管（LED）显示屏测试方法》,针对LED显示屏的一些重要考核指标如亮度、均匀性、视角和安全等,探讨如何提升LED显示屏的质量。     

An experimental radome panel evaluation

Modern antenna radomes are made of materials that tend to shed water to minimize their RF attenuation when wet. The microwave performance of these materials has been studied experimentally. Radome attenuation was measured as a function of frequency, rain rate, rain incidence angle, RF incidence angle, and polarization. The tests were performed on (1) new, clean radome panels, (2) used, dirty radome panels, (3) cleaned, used radome panels, and (4) panels treated with hydrophobic paint. The results show weak loss dependence on frequency over the 13-20 GHz frequency range of interest, which increases slowly with rain rate from 2.5 to 29 mm/h except for surfaces that are wettable, where the dependence on rate is much stronger. Loss is nearly independent of rain incidence angle, but it is strongly a function of surface condition. Hydrophobic paint is shown to be very effective. The test setup used, limitations imposed by the real world, and a simplified model of radome loss derived from the test results are described     

Millimeter Wave Attenuation through Illuminated Semiconductor Panel

Attenuation of millimeter wave energy through light-illuminated semiconductor panels is determined. The expressions for the attenuation are applied to cases of uniform circular light excitation and laser beam excitation of the panel. Families of curves are given for the attenuation as a function of ratio of distance from the center of excitation to the diffusion length of the semiconductor material. The effect of surface recombination velocities of semiconductor panels is also considered.     

Scaling theory of liquid-crystal displays addressed by thin-filmtransistors

The proposed scaling theory for designing thin-film transistor/liquid-crystal displays (TFT/LCD's) addresses the need for a new design theory for fabricating TFT panels. A constant field is assumed, the same as for MOSFET scaling. A constant voltage is assumed based on the fact that the operational voltages of liquid-crystal cells are not easily scaled. Scaling is found to improve the gate delay and offset voltage characteristics in spite of the narrower busline width and the smaller pixel capacitance. The same improvements are observed even in larger, higher-resolution panels. This scheme to scale the pixel capacitance can be extended to an unloaded-pixel scheme in which there is no storage capacitance in the pixels. The trade-off in this scheme is between a short charging-time constant and a large aperture ratio, and a large voltage offset and a short discharging-time constant. The scaling theory is shown to be a valuable tool to design the next-generation TFT panels     

适合产业化的显示屏化学减薄工艺的研究

超薄显示技术已成为市场的一种主流趋势。本文利用刻蚀后清洗的间歇式工艺研究了显示屏半成品的化学减薄。在光刻胶和边框胶保护下,调整氢氟酸浓度,加入一定量的硝酸、浓硫酸和盐酸,并添加超声辅助条件,刻蚀速率明显提高。通过交替的清洗工艺有效地降低了表面粗糙度,并减少了表面白色附着物的沉淀。显示屏厚度从0.8mm减薄到0.3mm,基板表面粗糙度为11.32nm,厚度均匀性为4.76%。设计的间歇式减薄工艺可以应用到现有的显示屏生产工艺中,为制作超薄液晶显示屏和超薄有机发光显示屏提供了一条可行的方案。     

邦达不燃轻质板墙的隔声研究

邦达不燃轻质板是一种新型建筑材料。介绍了该板与75mm轻钢龙骨组成的6种构造板墙实测的隔声特性。比较分析了板的不同层数和有无玻璃棉夹芯对板墙隔声的影响。从二层增加到四层,隔声量提高6dB;板墙中增加玻璃棉夹芯层,隔声量也提高6dB。带玻璃棉夹芯的四层板墙的隔声量高达60dB。     

路灯光伏系统中太阳电池板的安装位置

以遵义市为例,通过对城市道路和草坪的遮光分析,认为城市中地面的遮光比较严重,应该灵活处理光伏系统中太阳电池板的安装。提出在形成遮光的区域把太阳电池板和灯杆分离,将太阳电池板安装在建筑物或不遮光的空地上更能发挥太阳电池的作用,优化光伏系统的结构,降低光伏发电成本。     

PDP巨头反击与LCD争夺市场份额

Market leader Matsushita Electric Industrial Co. （Panasonic） and Hitachi Ltd. announced an agreement to supply each other with giant plasma panels for televisions. Starting in fiscal 2007, Matsushita will supply Hitachi with 103-inch panels, and in fiscal 2008, Hitachi will reciprocate by supplying Matsushita with 85-inch panels.     

Autonomous robot for cleaning photovoltaic panels in desert zones

In desert zones, a continuous cleaning activity of photovoltaic panels in solar plants is required since the deposition of both airborne dust and sand after a storm can reduce their efficiency up to 80%. Manual cleaning of the photovoltaic panels in dry areas is costly, cannot make use of water and workers must be employed several times in a month, often under extreme environmental conditions. For all these reasons, the research of cleaning solutions performed by autonomous robotic systems are seen beneficial to recover the solar panels efficiency at reasonable costs also nightly. In this respect, this paper presents the implementation of an unmanned low-cost robotic device operating without rails or guides for waterless dust and sand removal from the surface of photovoltaic panels. The robot autonomously moves as a half-track and gently wipes the dust away by means of a couple of independent helical brushes that alternatively rotate, according to a defined combination of the cleaning and motion strategy. Moreover, in real-time the robot detects its spatial position by ultrasonic sensors, regulates both its speed rate and motion direction. The on-board control system, based on an ARDUINO DUE platform, settles the robot travel direction, its speed and which brush must be activated for cleaning. Experimental tests have been performed by fabricating a prototype of the device to assess its effectiveness and reliability in terms of the autonomous motion, dust removal and low power consumption.     

A 60 line per inch plasma display panel

Gas discharge plasma display panels have been under development at Owens-Illinois for several years. This display device offers many advantages including: 1) tube depth (approximately ½ in) essentially independent of display size; 2) random write capability; 3) controlled information storage; 4) selective erase and bulk erase capability; 5) positive registration of displayed information; and 6) rear projection and/or printout capability. Panels, now available (DIGIVUE® display/memory unit), with 33⅓ and 40 electrode lines per inch are appropriate for many applications. However, a somewhat higher resolution of 50 or 60 lines per inch is desired for most general-purpose individual console displays when the number of lines inXor inYexceeds several hundred. The lower density Owens-Illinois panels are constructed from a parallel plate structure that was selected because of its compatibility with high volume manufacturing processing. This study indicated that the same basic structure could be used at resolutions up to 60 lines per inch. Design dimensions were optimized for this higher resolution and good dynamic operation was obtained. Process techniques were developed to produce panels with 256 by 256 lines and 512 by 512 lines. Several panels of each of these sizes were fabricated and evaluated. The performance of these 60 line per inch panels was comparable to that of the 33 line per inch panels.     

On Analysis and Optimization of an Active Cable-Mesh Main Reflector for a Giant Arecibo-Type Antenna Structural System

The active cable-mesh main reflector of a giant Arecibo-type antenna can adjust the illuminated area to a given parabolic surface in time, which is achieved with a flexible cable-mesh structure. This paper addresses the feasibility of the active cable-mesh main reflector, including accuracy adjustment and the influence of the panel curvature. The illuminate area of the reflector needs to be adjusted to a paraboloid, which is implemented by introducing a bias distribution field vector of mesh surface and least norm solution for under-determined equations. Plane panels and spherical panels are investigated. Numerical results show that a much more better surface precision can be obtained using spherical panels     

LED显示屏驱动技术讨论：动态响应

LED驱动芯片的动态响应特性经常被忽略,但却是相当重要的一个特性。动态响应影响LED显示屏的影像质量,如灰阶、线性度、EMI、信赖性。虽然这些特性彼此间有取舍关系．但是好的驱动芯片应该能够在这些特性中取得较佳的平衡。本文将探讨动态响应的重要性及LED驱动芯片与电路板设计技术,以协助工程师设计出影像质量良好的显示屏。     

天线罩在地面天线系统中的应用

介绍了不同口径天线中使用的截球型天线罩的外形结构、电气性能指标,这种天线罩由玻璃钢单元件搭接拼装而成,采用随机分块,拼缝经过结构和电调谐.由于采用了新技术、新工艺,各项性能指标均超过欧洲进口天线罩,具有抗风能力强、外形美观、安装方便、电性能优秀、防漏雨和抗盐雾侵蚀性好的特点,可在各种环境条件下使用,应用前景广泛.该天线罩的设计方法对同类天线罩的设计有借鉴作用.