新型大屏幕彩电蓝背景控制电路的原理与检修

<正> 现在的新型大屏幕彩电大都设置有蓝背景控制电路,以便彩电在无信号或电视信号行不同步时电路自动切换,使显像管的屏幕上呈现背景光栅。各种新型大屏幕彩电的蓝色背景控制电路的结构大同小异,工作原理基本相同。下面以乐华R-3303型33英寸大屏幕彩电为例,介绍蓝背景控制电路的原理。由于蓝背景控制电路与字符显示电路联系较为紧密,故先简略地介绍一下字符显示信号流程。然后介绍蓝色背景显示控制电路的原理。     

LED大屏幕控制电路设计方案研究

在综合分析LED大屏幕显示系统设计中控制电路的诸多设计方案的基础上，分别给出了以单片机、可编程逻辑器件和嵌入式计算机技术为控制核心的不同设计方案的实现方法，对这几种方案的特点进行了比较，并介绍了应用情况。     

大屏幕温度及时间显示器的研制

大屏幕时钟及温度显示器目前广泛应用于各种场合，然而目前市场流行的大屏幕时钟及温度显示器均存在时间数据修改困难的缺点，而时钟数据会因使用时间长而产生积累误差，因此必须修改。针对此问题。以AT89C52单片机作为控制核心，采用了红外遥控技术进行编码和解码，实现了10米以内，可稳定有效遥控修改时钟数据。     

基于红外遥控技术的大屏幕时间显示器的研制

文章以AT89C51单片机作为控制核心,采用了红外遥控技术进行编码和解码,实现了10m以内稳定有效遥控修改大屏幕时钟显示数据.     

会展用大屏幕LED显示系统的设计与实现

LED显示系统是半导体技术的一种典型且广泛的应用。文中设计了一种适合会展用的LED显示系统,该显示系统分为硬件系统和软件系统,在由输入信号的控制下,完成数据的储存与更新、画面显示、动画处理等功能。设计的大屏幕LED显示系统,只需要辅以简单的外围电路即可满足会展时大屏幕LED的使用,增强了LED大屏幕的普适性。实际应用表明该设计稳定可靠,具有较强的实用性。     

单片机大屏幕温湿度测控电路

附图是一款大屏幕LED显示的温湿度测量与控制电路.使用自带12位A/D转换功能的SN8P1704A单片机为核心制作(有关SN8P1704A的资料,可以参考本刊2004年5月的<用SN8P1704制作通用数字电压表>一文).     

LED大屏幕显示系统的对比度与亮度调节技术

提出了一种实现LED大屏幕显示系统的亮度与对比度调节技术，介绍了该技术的算法与实现电路。     

大屏幕显示器件综述

本文介绍了各种显示器件在大屏幕显示中的应用，以及它们实现大屏幕显示的方法，并讨论了各类显示器件在大屏幕应用中优缺点和研制动态。     

一种工业显示屏的设计

一种为自动控制系统设计的工业显示屏,具有数码显示、指示灯显示和语音提示功能.文中介绍以单片机为核心的硬件电路结构、SPI接口的显示驱动电路、语音提示控制电路以及相关设计思想.     

基于VRS51L3074的LED显示屏控制系统

介绍市场上第一款内嵌铁电存储器的高性能8051单片机VRS51L3074,重点分析该单片机SPI模块的CS3扩展功能,说明了LED显示屏的工作原理,设计了基于VRS51L3074的LED显示屏控制系统,对输出电路进行了优化.实现了显示数据以"直接存储器访问(DMA)"方式输出.     

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.     

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.     

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.     

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.     

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.