共查询到18条相似文献,搜索用时 62 毫秒
1.
2.
3.
可实现存储光栅快速增强的新型全息存储结构 总被引:4,自引:0,他引:4
提出一种新型全息数据存储结构,该结构包含两块存储的内容完全相同的光折变晶体,无需相位共轭器,仅利用两束时域快速调制的平面参光波便可实现对存储全息图的迅速增强。文章讨论了调制速率,读出光强比,晶体非线性耦合强度及初始光栅强度对增强速度及可获得的饱和衍射效率的影响。 相似文献
4.
数字体全息数据存储中的两种信道编码方法 总被引:1,自引:0,他引:1
本文提出的用于数字体全息数据存储系统的两种信道编码方法,不但可有效抑制系统中各种大尺度噪音的影响,而且有利于多重体全息图的均匀记录,并可简化存储器进行内容寻址操作时匹配阈值的设置.文章讨论了两种编码方法的实现复杂度,分析了其误码率性能. 相似文献
5.
全息透镜用于彩色胶片全息高密度存储 总被引:1,自引:0,他引:1
本文提出一种利用全息透镜实现彩色胶片全息高密度存储的方法。用红、绿、蓝三基色激光分别记录三个焦距相同的全息透镜,用三个全息透镜依次用三基色波长记录胶片的傅氏全息图,用原参考光照明再现,可合成彩色像。 相似文献
6.
7.
大数据时代对数据存储提出了新的要求,为克服目前存储技术无法逾越的障碍,全息存储回到人们的视野,为了解决传统全息存储的记录密度与理论值相差较大的问题,本文作者团队提出了将光的振幅、相位和偏振均作为调制变量的多维调制全息数据存储技术;为验证多维调制的实验结果,针对具有偏振响应的全息存储材料特性提高方面也开展了研究。这些研究成果加速了全息存储技术应用的产业化步伐。本文以该团队在北京理工大学期间开展的多维调制全息数据存储技术的研究成果为基础,分别从光的振幅、相位和偏振调制机理出发,综述了各个调制方法的理论基础和应用实例,以及提高全息存储材料性能的有效手段,最后进行了总结和展望。 相似文献
8.
9.
分析传统磁存储及光盘存储的极限,概述体全息存储的基本原理及特点,并重点介绍该技术最新的研究动态和未来发展方向。 相似文献
10.
根据全息存储二值图像的特性,提出了评价重构图像信噪比的方法,并对掺铁铌酸锂晶体中角度复用全息存储图像的信噪比作了详尽的定量研究,包括存储过程中图像信噪比的动态演变,以及页内和页间串扰对重构图像信噪比的影响.测量结果表明,串扰噪声引起的信噪比下降趋势与理论分析一致,图像信噪比的恶化主要是由于相干光学噪声和测量仪器的噪声;实验结果还表明即使在较小的衍射效率下也可获得较好的存储图像信噪比,从而为存储容量和图像质量之间的最佳均衡创造了条件. 相似文献
11.
实验研究了基因改性菌紫质BR_D96N薄膜在不同偏振光记录下的全息存储特性,比较了不同 偏振态记录光和读出光对衍射像光强及信噪比的影响. 实验结果表明,与其他偏振全息记录 相比,正交圆偏振光记录可实现衍射光偏振状态与散射噪声偏振状态的分离,得到高信噪比 的衍射像,同时还具有高的衍射效率. 以 He_Ne 激光器(633nm,3mW)为记录和读出光源 ,用空间光调制器作为数据输入元件,CCD作为数据读出器件,采用傅里叶变换全息记录的 方法,在 BR_D96N 薄膜样品60μm×42μm的面积上进行了正交圆偏振全息数据存储,达到 了2×108bit/cm2的存储面密度,并实现了编码数据的无误读出与 还原.
关键词:
菌紫质
偏振全息
光致变色
光致各向异性
高密度光存储 相似文献
12.
13.
近场光学在高密度存储中的应用 总被引:3,自引:0,他引:3
近场光学在高密度存储方面有着很大的潜力 ,使得近场光学存储近年来得到了广泛的关注。近场光学存储具有高密度大容量及可以利用许多已有相关技术等优点 ,预计近场光学存储密度能达到 7Gbit/ cm2 ;它还可以采用硬盘驱动器中的空气悬浮磁头技术和磁光存储中的技术等 ,使近场存储的研究和开发更加迅速。目前 ,近场光学存储主要有三种方案 :探针型方案、超分辨率近场结构、固体浸没透镜方案 ,这三种方案都是通过不同的方法缩小记录光斑来实现高密度的存储。介绍了近场光学存储的原理、研究现状及材料 ,并对三种近场存储方案的实现方法和发展概况作了详细的阐述 ,分析了这三种方案的优缺点 相似文献
14.
15.
二极管激光泵浦固体激光器和稳频研究 总被引:1,自引:0,他引:1
用调制法布里-珀罗干涉仪方法稳定二极管激光泵浦的NdYVO4单频激光器的频率。在锁定情形下,激光频从自由运行慢漂移1.43MHz/s和抖动±2.5MHz分别改善到75.75kHz/s和±1MHz 相似文献
16.
Ruggedized digital holographic data storage with fast access 总被引:2,自引:0,他引:2
Recent investigations in holographic mass memory systems have produced proof-of-concept demonstrations that have highlighted their potential for providing unprecedented capacity, data transfer rates and fast random access performance (Heanue et al. 1994; Hong et al. 1995; Psaltis and Mok 1995; Bernal et al. 1996; McMichael et al. 1996). The exploratory nature of most such investigations has been largely confined to benchtop experiments which have ignored the practical constraints of packaging and environmental concerns. We have embarked on an effort to demonstrate the holographic mass memory concept by developing a compact prototype system geared for avionics and similar applications which demand the following features (mostly interdependent factors): (1) solid state design (no moving parts), (2) fast data seek time, (3) robust with respect to environmental factors (temperature, vibration, shock). In this paper, we report on the development and demonstration of two systems, one with 100 MB and the other with more than 1 GB of storage capacity. Both systems feature solid state design with the addressing mechanism realized with acoustooptic deflectors that are capable of better than 50 sec data seek time. Since the basic designs for the two systems are similar, we describe only the larger system in detail. The operation of the smaller system has been demonstrated in various environments including hand-held operation and thermal/mechanical shock; a photograph of the smaller system is provided, as well as actual digital data retrieved from the same system. 相似文献
17.
M. Sutkowski T. Grudniewski R. Zmijan J. Parka E. Nowinowski-Kruszelnicki 《Opto-Electronics Review》2006,14(4):335-337
Liquid crystal devices as a medium for holograms storage have been investigated. Long term memory effects in LC cells have
been observed. Experiments proved that certain combination of insulating alignment layers has a major influence on the long
term memory effect. Optimal liquid crystal cell construction allows us to achieve sufficient diffraction efficiency to record
holographic patterns and to develop a re-writable holographic medium. The configuration of PVK and polyimide layers in LC
cell construction with specific LC mixture was tested. The method of permanent and re-writable recording of optical data (holographic
pattern) onto LC cells was achieved. However, the method of erasing recorded data was realized but mechanisms of this phenomenon
are not clearly understood yet. 相似文献
18.
We propose a method for gray level holographic digital data storage by using three-gray levels in the phase mode. Gray level data pages are displayed on a SLM operating in the phase mode to obtain a homogenized Fourier spectrum by suppressing the extremely high intensity DC component in the Fourier spectrum of conventional amplitude based binary/gray level data pages. Holographic interferometry has been used to recover the gray level amplitude data page from phase data page. Numerical simulation results are presented for three-gray level data pages. Fourier plane homogeneity, bit-error-rate, storage density, phase modulation error of the SLM, and misalignment tolerances are investigated through computer modeling. A comparison of the present method with the amplitude-modulated gray level case with and without using a phase mask in conjunction with the data page is carried out. An experimental demonstration of the proposed three-gray level phase data page method is also presented. 相似文献