共查询到20条相似文献,搜索用时 62 毫秒
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随着信息科学的迅速发展,对存储介质的存储密度和存储容量的要求在不断提高,然而传统的信息存储方法已几乎接近物理极限,于是寻找新的存储介质和存储方法就成为近年来信息科学的研究热点。光存储技术是继磁存储技术之后的又一新兴技术,它利用光改变物质物理或者化学性质存储信息,近年来不仅取得了重大的技术突破,而且形成了一个庞大的产业。现在以光盘为代表的光学数字数据存储技术已成为信息存储中不可缺少的载体。与以往的磁存储相比,光盘存储的优点是存储容量大、密度高、寿命长、信息的信噪比高,可以非接触式读写和擦除等。 相似文献
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The advantages of read-only storage is the predominance of optical recording
relative to magnetic and other rewritable methods. Multilevel (ML) read-only
technology has been a trend to improve the data capacity and transfer rate. Based on
the principle and coding method of ML, this paper demonstrates some ML read-only
recording methods, of which a new ML read-only recording is developed. This
recording method integrates amplitude modulation achieved by the reaction mechanism
of physics and chemistry of photoresist with the run-length-limited technology. The
discs can be achieved using standard photoresist mastering and replication
techniques with great compatibility to conventional binary read-only discs. 相似文献
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介绍了可用于可录、可擦除、全息光存储及超分辨掩膜层的氧化物、次氧化物薄膜材料的种类、制备方法、光存储特性和存储机制。这类薄膜材料由于具有种类多、应用范围广、制备方法多样、写入灵敏度高和记录稳定性好等优点 ,正受到各国研究者越来越多的关注。分析总结了这类材料的研究现状、存在的主要问题和未来发展方向 相似文献
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用金属有机物化学气相沉积法外延制备了一个透射式蓝延伸GaAs光电阴极,积分灵敏度达到1980 μA/lm,同时与美国ITT公司的一条蓝延伸阴极光谱响应曲线对比,分别对两者进行了光学结构拟合. 结果表明,国内阴极在Ga1-xAlxAs层厚度、Al组分、电子扩散长度和后界面复合速率上与国外 存在差距,这导致国内阴极的蓝延伸性能不及国外.国内蓝延伸阴极的表面电子逸出几率、发射层厚度与 国外阴极拟合结果一致,这使得两者长波响应性能差别远小于短波部分的差别.另外响应波段全谱的吸收率 小于国外阴极,导致国内透射式蓝延伸GaAs光电阴极光谱响应、积分灵敏度尚不及国外. 相似文献
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基于Polytec激光测振仪的光存储设备振动测试分析系统 总被引:2,自引:0,他引:2
针对光存储设备振动频率高的特点,采用Polytec激光测振仪拾取振动信号,并给出了基于Polytec激光测振仪的光存储设备振动测试分析系统。可用于硬盘盘片、磁头滑块、折臂组件、光盘盘片等振动测试,为光存储设备动态特性的测试和分析建立了良好的实验基础。 相似文献
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Kai Zhong Gao Olle Heinonen Yonghua Chen 《Journal of magnetism and magnetic materials》2009,321(6):495-507
In this paper, we present a review of the write and read processes in perpendicular magnetic recording. We also discuss their impact, based on recording physics aspects, on design considerations for writers and readers. For the write process, we discuss fundamental write-ability limitations as well as possible paths to ultra-high areal density perpendicular recording. The impacts of different medium designs, geometrical scaling, and the breakdown of scaling, both in terms of write-ability and transition curvature, are shown based on different modeling techniques, including analytical formulas, finite element modeling (FEM), and micromagnetic simulations. Basic design rules as well as alternative designs that enable high areal density are briefly explained. For the read-back process, the relation between reader signal to noise ratio (SNR) and resistance, as well as reader resistance shunt and spacing loss, are discussed. Finally, we use a simple example to illustrate, both from a write as well as a read-back perspective, the complicated nature of perpendicular recording systems, and how different medium designs impact recording head technology for ultra high density perpendicular recording. 相似文献
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运用矢量衍射理论的计算方法(耦合波方法,时域有限差分法),对两种多阶光存储方案(坑深调制,坑形调制)进行了原理性分析,并简略分析了利用相变材料的幅值调制实现多阶存储的原理.由此得出多阶光存储技术的实现是利用了光与物质之间的相互作用,使光对记录介质产生作用,同时介质也对光的某些特性进行调制,而这些特征的改变一般都不止两个状态0或1,用数字方式将这多个状态记录下来便实现了多阶数字存储.此外,还提出了多阶光盘前端信号处理系统的设计与开发.该系统是多阶光存储实验系统的重要组成部分,可输出RF,TE,FE等伺服与误差信号,并将信号反馈给多阶处理芯片;同时系统还可对光学头的激光读写功率及写入时间进行控制,并能使其实现自动调焦和道跟踪.
关键词:
多阶光存储
矢量衍射理论
时域有限差分法 相似文献
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The extended boundary condition method is applied to both circular and elliptical regions for calculating cutoff frequencies Vc of weakly guiding optical waveguides, which consist of a uniform cladding and a core with arbitrary shape and index profile. The frequency shift formula method is explained by means of the extended boundary condition method on circular regions. Comparing the method with analytic and other rigorous methods, we show that it is indeed a powerful tool. Numerical results confirm that the mode designation and arrangement order in elliptical and rectangular waveguides are, in general, dependent on the aspect ratio. 相似文献
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光信息科学与技术专业的建设 总被引:1,自引:0,他引:1
就光信息科学与技术专业建设的专业定位、课程设置、学生毕业后的去向等问题发表了个人的看法。介绍了在这方面的一些做法,提供了有关数据,可供同类专业的建设参考。 相似文献