数字录像机的技术性能与选型分析

目前,广播电视正处在从模拟向数字过渡时期,从数字化发展趋势和当前产品的实用水平看,将来的录像机必定是数字处理的录像机,数字录像机的应用将大大提高电视信号的质量,使电视节目的制作、播出和传输发生质的飞跃。随着数字技术的发展,数字录像机的质量、功能、系统配置日臻完善,各电视台现在使用的模拟录像机将逐渐被数字录像机所取代。针对现今多种格式的数字录像机,     

数字录像机模型及实现

本讲述了数字录像机的基本概念、优点。描述了理想数字录像机的结构、原理。并介绍了目前国内出现的几种数字录像机解决方案。最后对数字录像机的广泛应用做了总结和归纳。     

松下数字录像机特殊功能的操作

目前无论中央电视台还是各地方电视台或电教馆多数采用模拟分量录像机或模拟复合录像机，而近两年数字录像机已经成熟并打入市场，开始为广播电视服务。录像机的数字化意味着视频信号各种处理的数字化；声音、视频和控制信号传输的数字化；各种控制、调整和自我诊断信号的数字化。数字录像机无论是在声音、视频质量上，还是本机功能上都是模拟录像机所不及的。根据各厂商设计人员思路不同，数字录像机在信号处理上分别采用压缩和非压缩两种方式。我台目前后期机房使用的数字录像机有SONY公司的DVW-500P，DVW-510P；松下公司的AJ-D350E数字录像机等。本仅对松下数字录像机的特殊功能加以介绍。     

浅谈数字BETACAM录像机的特点

引 言 数字录像机的发展已有十几年的历史。早在1987年和1988年,索尼公司分别发表了3/4英寸D1格式数字分量录像机及D2格式数字复台录像机。1990年及1993年,松下公司又分别发表了D3格式1/2英寸数字复合录像机及D5格式1/2英寸数字分量录像机。它们都有很高的图像及声音质量,多带复制能力很强,但由于其生产和使用成本非常昂贵,无法得到普及。随着数字压缩技术的突破性进展及纠错技术能力的提高,1993年索尼公司推出了数字Betacam录像机,1995年JVC公司推出了Digital—S数字录像机,同     

DVCRPO数字录像机的维护保养与故障处理

目前各电视台大量采用数字录像机,数字录像机已成为电视台的主流机型,相较于模拟机型,数字设备记录的音质、图像效果优越,但价格较昂贵.目前市场上数字设备主要集中在两大公司,其生产的数字录像机格式不同,各电视台也多为两种不同格式的数字录像机共存,下面介绍松下DVCRPO数字录像机在使用中应如何维护保养.     

数字录像机中的误码修正和补偿

数字录像机与模拟录像机一个最基本的差别是误码修正和误码补偿技术。在数字录像机中,有了这种技术就能使S/N较差,但只要在允许范围内的情况下完全恢复原来的数据。这在模拟录像机中是完全不能做到的。这种技术对录像机的复制特性是一关键性贡献。但反过来说,如果数字录像机没有     

浅析数字录像机的发展动态及应用

通过数字录像机的发展状况,压缩技术及在非线性编辑中硬盘录像机的使用,分析了数字录像机的性能、原理。     

消费电子产品的新领域：数字磁带录像机

可供录像,放像的家用数字磁带录像机已经研制成熟,并有少量产品问世,本文扼要概述了将成为新一代家用录像机换代产品的ＤＶ数字录像机以及用于数字广播接收的Ｄ－ＶＨＳ数字录像机的记录格式体制,技术规范,类型和主要功能。     

数宇录像机中的误码修正和补偿

数字录像机与模拟录像机一个最基本的差别是误码修正和误码补偿技术。在数字录像机中，有了这种技术就能从S／N较差但只要在允许范围内的情况下完全恢复原来的数据。这在模拟录像机中是完全不能做到的。这种技术对录像机的复制特性是一关键性贡献。但反过来说，如果数字录像机没有误码修正能力，那么它的复制特性就差得多。因此误码修正技术一直是数字录像机研究的重要课题。     

盒式磁带录像机的维护

随着电视技术不断发展，电视设备数字化呈必然趋势。数字录像机已进入实用阶段。数字录像机以其优良技术指标和优质的画面正引起各家电视台的注意。但是，数字录像机和数字录像带因其价格昂贵等其他原因（比如制式）要达到普及仍需相当长的时间。我们通常使用的录像机仍然是以Sony SP系列为代表的盒式磁带录像机。下面就盒式磁带录像机的维护和保养谈一下体会，供有关人员参考。     

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.     

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.     

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.     

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.     

避免MOS管在测试时受EOS损坏的方法

由于MOS管是浅结系列产品,极有可能在测试时遭到静电击穿或过压过流而损坏。文中主要介绍MOS管在测试过程中,会造成实际测试时器件加上了允许的最大电压、电流或功率而导致器件损坏的情况。例如,在测试过程中电源连接不良,测试片与器件接触不良,管脚接错,在测试程序中未设置正确的电压和电流钳位或DUT板损坏等。然后,针对此类现象的发生,提出了在测试过程中应采取的相应措施,从而有效地保证产品质量。     

一种改善LED背光亮度均匀性的新型反射膜研究

在LCD的LED背光腔体的底面设计了新型曲面形状及性能的反光膜,将扩散膜反射回灯腔底部的光重新反射回出光口以改善亮度均匀性能;在侧面设计了镜面反射膜,将位于LED矩阵边缘区域由LED射向灯腔侧壁的光反射重新射向出光口,增加了LED背光边缘区域的亮度,从而改善了背光边缘区域较暗的亮度不均匀状况.根据此类反射膜的设计完成了反射膜的制备,并应用于38 cm LED背光源样品.测试结果显示,设置反射膜的LED背光的亮度均匀性值为10.2%,明显优于未设置反射膜的值16.8%,亮度提高了29%左右,表明该种新型反射膜可以提高亮度并改善亮度均匀性.     

圆球微腔对水蒸汽的敏感特性仿真实验研究

研究了圆球微腔在水蒸汽传感中应用的可行性。通过测试在有/无水蒸汽的气室环境下,圆球微腔透射光谱的变化来对气室水蒸汽浓度情况进行传感测试。仿真实验结果显示:在有无水蒸汽干扰的条件下系统输出光强有明显的变化,即研制基于圆球微腔的传感器是可行的。     

位屏蔽多叉树搜索射频识别防碰撞算法

针对RFID树型防碰撞算法中时隙数多、数据通行量大等问题,提出了一种改进的多叉树防碰撞算法,阅读器准确检测碰撞位并向标签反馈碰撞位信息,标签对阅读器已知的ID位进行屏蔽,把ID号转换成连续碰撞的序列号.阅读器利用屏蔽位信息和标签返回的碰撞位编码信息,对标签进行分层分类搜索.通过对标签ID进行屏蔽,阅读器和标签间仅发送对方不知道的碰撞位信息.该算法减少了碰撞时隙和识别时隙,避免了空闲时隙,减少了阅读器和标签间的数据通信量.理论分析和仿真结果表明,该算法减少了系统的时隙总数和数据通信量,提高了阅读器的识别效率.     

Design and nonlinearity compensation of Fabry-Perot type tunable optical filters for dynamic strain sensing systems

The collected spectrum of the fiber Bragg grating （FBG） and the loss of the detected optical power are discussed with respect to the 3-dB bandwidth of a Fabry-Perot （F-P） type tunable optical filter （TOF）, respectively. And the optimized parameters of the TOF are obtained consequently. It is demonstrated that the relationship between the transmission wave- length of the TOF and its drive voltage is nonlinear. A new method to compensate the nonlinearity of the TOF is proposed. The linear sweeping of the transmission wavelength of the TOF is achieved through modifying the drive voltage using interpolation algorithm. It is observed that the average error and the maximum error of the transmission wavelength are reduced sharply under linear fit. The dynamic strain sensing is realized by use of a reference FBG and moving averaging algorithm in this system.     

Quantum theory analysis of the action micromechanism exerted on bioparticles from laser microbeams

The effect of laser microbeam trapping the bioparticles has been appfied widely in the biology .However the micromechanism of the acting that realizes the laser-microbeam trapping bioparticles is still lacking. In this paper ,the act microchenism of the gradiant force of laser microbeam for the bioparticles is analysed by means of quantum theory ,The result accords with our experiment.