CN1274915A - 固定式三维光子存储装置 - Google Patents
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- 239000013078 crystal Substances 0.000 claims abstract description 36
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 22
- 229910052742 iron Inorganic materials 0.000 claims description 10
- GQYHUHYESMUTHG-UHFFFAOYSA-N lithium niobate Chemical compound [Li+].[O-][Nb](=O)=O GQYHUHYESMUTHG-UHFFFAOYSA-N 0.000 claims description 9
- WSMQKESQZFQMFW-UHFFFAOYSA-N 5-methyl-pyrazole-3-carboxylic acid Chemical compound CC1=CC(C(O)=O)=NN1 WSMQKESQZFQMFW-UHFFFAOYSA-N 0.000 claims description 7
- 239000011777 magnesium Substances 0.000 claims description 4
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- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 2
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 2
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- 229910052738 indium Inorganic materials 0.000 claims description 2
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 claims description 2
- 229910052749 magnesium Inorganic materials 0.000 claims description 2
- 239000011701 zinc Substances 0.000 claims description 2
- 229910052725 zinc Inorganic materials 0.000 claims description 2
- 230000005055 memory storage Effects 0.000 claims 1
- 230000003287 optical effect Effects 0.000 abstract description 3
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- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
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- G11B7/125—Optical beam sources therefor, e.g. laser control circuitry specially adapted for optical storage devices; Modulators, e.g. means for controlling the size or intensity of optical spots or optical traces
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- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/12—Heads, e.g. forming of the optical beam spot or modulation of the optical beam
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Abstract
本发明属信息存储。它包括计算机、精密转台、写入光源、读出光源、透镜、空间滤波器、空间光调制器、反射镜、相位失配调整器、光折变晶体(如双掺铌酸锂等)与CCD构成;利用绿光(532nm)作为写入光,红光(670nm)作为读出光,使得图像的信噪比大大提高,并解决了光固定的难题。采用透射式配置,并利用双凸非规则透镜作为相位失配调整器,大面积无畸变的复现存储图像,并利用动态差分编码解码技术,实现了海量高速数字存储的目的,并有效的降低了误码率(小于10-6)。
Description
本发明属信息存储。
现有存储器多采用二维存储方式,如磁盘、光盘等,存储容量一般可达10GBytes,目前最高为35GB,存取速率不超过1MB/s,因此已远远不能满足未来信息存储、传输与处理的要求。高密度数据存储技术始终是信息技术和计算机技术发展中不可缺少的关键研究领域,预计到2005年,新型网络系统和第三代多媒体出现时,计算机外部存储容量至少应为100GB,数据传输率至少为40MBps,现有的各种外存设备都不能满足要求,即使目前刚进入市场的DVD光盘系统也与此目标相距甚远。唯一的出路是利用新原理、采用新技术、启用新材料才有可能研究开发出新一代高密度、高速存储技术和系统。
以全息存储为基础的三维存储技术同时具有容量大、数据传输速度高、数据搜索时间短等优良性能。三维体全息技术以页面全息图的方式并行地在介质的整个体积内进行信息存储和检索。理论估计存储密度可达1013bits/cm3,数据传输速率可达到或超过109bits/s,读取一个数据页面(每页包含高达106bits)的时间小于100μs。但现有的关于三维存储器的研究通常采用90度配置,并利用绿光光源作为读出光源,固定时间难以保证,并且系统不易小型化。
本发明目的是提供一种固定式三维光子存储装置,它是一种三维存储系统,可以实现信息的海量存储,并达到高速存储与读出的目的,解决光固定时间难以保证的难题,使其更好地应用于多媒体数据等信息的存储,适应未来信息高速发展的需要。
本发明包括写入系统和读出系统,写入系统包括计算机、精密转台、写入光源、透镜、空间滤波器、空间光调制器、反射镜、光折变晶体(如单掺、双掺铌酸锂,钽酸锂)与电荷耦合器件(CCD)构成;读出系统包括计算机、精密转台、狭缝、相位失配调整器、读出光源、光折变晶体(如单掺、双掺铌酸锂,钽酸锂)、透镜与CCD构成。读出系统中使用的光折变晶体是利用写入系统记录了信息的光折变晶体。
从透镜106和反射镜108出射到光折变晶体107上的两束光的夹角为2θ,10°≤θ≤35°;相位失配调整器202的出射光和从光折变晶体204到透镜207的衍射光夹角为180°-2α,α和θ的关系为λwsinθ=λrsinα,其中λw和λr分别为写入光和读出光的波长。
空间光调制器由计算机控制显示所要存储信息,光折变晶体被固定在精密转台上,精密转台由计算机控制可转到需要的任意角度,CCD采集的图象送回计算机进行处理。在使用绿光记录红光读出时要使用相位失配调整器,以达到相位匹配的目的。相位失配调整器为双凸非规则透镜,横向焦距为50~400mm,纵向焦距为300mm~无穷大。
本发明的具体实施步骤:采用光折变晶体(如单掺、双掺铌酸锂,钽酸锂)作为三维全息存储光盘材料,利用晶体的光折变特性进行全息存储,采用绿光激光器(波长532nm)作为写入系统光源,采用小型半导体激光器(红光,典型波长670nm)作为读出光源,采用透射式配置存储,利用双凸非规则透镜作为相位失配调整器,采用动态差分方法进行编码和解码。
下面结合说明书附图详细描述本发明:
图1是写入系统示意图;图2是读出系统示意图。
(一)写入过程(图1):I、由计算机112控制将存储文件进行编码,形成编码图形,并控制空间光调制器104产生编码图像或存储图像(若直接存储图像);II、写入时用绿光激光器(波长532nm)100作为写入光源,写入光由激光器100发出后,经分束镜101分为二束光,其中一束光1经滤波器102滤波,再经透镜103准直,再经空间光调制器104调制成所需信息光后,经反射镜105反射,再经聚焦透镜106入射到晶体107上;另一束光2经反射镜108反射作为参考光直接入射到晶体107上,两束光在晶体107中干涉记录光栅。III、记录完毕后由计算机控制转台109转动角度进行下一存储图像的存储。从而达到存储多页全息图的目的。
(二)读出过程(图2):I、由计算机206控制转台203转到所需角度,用半导体激光器200作为光源,采用红光(波长650~690nm,典型波长670nm)作为读出光,读出光从激光器200发出后,经狭缝201调制后,再经作为相位失配调整器的双凸非规则透镜202,入射到晶体204上,其衍射光通过透镜207成像在CCD205上,CCD接收光图像信息,通过计算机进行解码并还原成计算机文件;II、计算机控制转台203转动在特定角度读取原来存储的特定图像(文件)。读出系统中使用的光折变晶体是利用写入系统记录了信息的光折变晶体。
本发明采用光折变晶体(如单掺、双掺铌酸锂,钽酸锂)作为三维全息存储光盘材料,不同晶体的组分如下:
同成分单掺铌酸锂: 掺铁0.02~0.05wt%
钽酸锂晶体: 掺铁0.02~0.05wt%
双掺铌酸锂晶体: 掺铁0.007~0.03wt%与掺镁1.0~5.5mol.%、
掺铁0.01~0.05wt.%与掺铟0.75~3.0mol.%或
掺铁0.02~0.06wt.%与掺锌1.5~6.5mol.%,
其中同成分配比为[Li]/[Nb]=0.87~0.95。
本发明的存储容量可表示为PQR,其中P为单页图的存储容量,P=1K~10Mbits,Q为在单点按某种编码方式可存入全息图的数目,在我们的装置中采用角度编码,单色存储方式下Q~1000,双色存储方式下Q~200,R为光折变晶体上可以利用的点的个数,R~20/cm3。我们在尺寸为1.2×1.4×0.45mm3的LN:Fe,Mg(Fe 0.02wt.%,Mg 1.0mol%)晶体内实现了0.5Gbits的数据存储,存储量至少可达到50Gbits/cm3。
本发明采用了透射式配置,利用绿光作为写入光,红光作为读出光,采用小型半导体激光器,使系统小型化、更紧凑,读出光波长(650~690nm,典型波长670nm)远离写入光的波长(532nm),由于光栅矢量的失配,大大抑制写入的噪音栅的读出,进一步提高图像的信噪比,实现高清晰度的图像再现。另外采用双凸非规则透镜作为相位失配调整器,可大面积无畸变的复现存储图像,并利用动态差分编码解码技术,实现了海量高速数字存储的目的,并有效的降低了误码率(小于10-6),同时解决了光固定的难题,使三维光子存储器真正实用化。
Claims (6)
1.一种固定式三维光子存储装置,其特征在于它包括写入系统和读出系统,所说的写入系统包括计算机、分束镜、精密转台、写入光源、透镜、空间滤波器、空间光调制器、反射镜、光折变晶体与CCD构成;所说的读出系统包括计算机、精密转台、狭缝、相位失配调整器、读出光源、光折变晶体、透镜与CCD构成;
所说的写入系统中,计算机(112)分别和空间光调制器(104)、精密转台(109)、CCD(111)连接,光折变晶体(107)固定在精密转台(109)上,分束镜(101)位于写入光源(100)的前方,分束镜(101)和反射镜(105)之间依次安放空间滤波器(102)、透镜(103)、空间光调制器(104),反射镜(108)位于分束镜(101)和光折变晶体(107)之间,透镜(106)位于分束镜(101)和光折变晶体(107)之间,透镜(110)和CCD(111)依次安放在光折变晶体(107)后与透镜(106)的对侧,从透镜(106)和反射镜(108)出射到光折变晶体(107)上的两束光的夹角为2θ,10°≤θ≤35°;
所说的读出系统中,计算机(206)分别和精密转台(203)、CCD(205)连接,光折变晶体(204)固定在精密转台(203)上,狭缝(201)位于读出光源(200)的前方,狭缝(201)后依次安放相位失配调整器(202)、精密转台(203),光折变晶体(204)后依次安放透镜(207)和CCD(205);相位失配调整器(202)的出射光和到透镜(207)的衍射光夹角为180°-2α,α和θ的关系为λwsinθ=λrsinα。
2、按照权利要求1所说的固定式三维光子存储装置,其特征在于所说的相位失配调整器(202)为双凸非规则透镜,横向焦距为50~400mm,纵向焦距为300mm~无穷大。
3、按照权利要求1所说的固定式三维光于存储装置,其特征在于所说的反射镜(105)和反射镜(108)可以只选用其中一个或再加入多个反射镜。
4、按照权利要求1所说的固定式三维光子存储装置,其特征在于所说的光折变晶体是单掺、双掺铌酸锂或钽酸锂,其组分如下:
同成分单掺铌酸锂:掺铁0.02~0.05wt%
钽酸锂晶体: 掺铁0.02~0.05wt%
双掺铌酸锂晶体: 掺铁0.007~0.03wt%与掺镁1.0~5.5mol.%、
掺铁0.01~0.05wt.%与掺铟0.75~3.0mol.%或
掺铁0.02~0.06wt.%与掺锌1.5~6.5mol.%;
其中同成分配比为[Li]/[Nb]=0.87~0.95。
5、一种固定式三维光子存储方法,其特征在于它包括下述步骤:
(1)由计算机将存储文件进行编码,形成编码图形,并通过空间光调制器产生编码图像或存储图像;
(2)用绿光激光器作为写入光源,激光从激光器发出后经分束镜(101)分为二束光,其中一束光1经滤波器(102)滤波,再经透镜(103)准直,再经空间光调制器(104)调制成所需信息光后,经反射镜(105)反射,再经聚焦透镜(106)入射到晶体(107)上;另一束光2经反射镜(108)反射作为参考光直接入射到晶体(107)上,两束光在晶体(107)中干涉记录光栅;
(3)记录完毕后由计算机(112)控制转台(109)转动角度进行下一存储图像的存储;
(4)重复(1)到(3)实现多幅图的存储;
所说的读出过程包括下述步骤:
(1)由计算机控制转台转到所需角度,用红光半导体激光器作为读出光源,读出光经狭缝(201)后,再经相位失配调整器(202),入射到光折变晶体上,衍射光经过透镜(207)成像在CCD上,CCD接收光图像信息,通过计算机进行解码并还原成计算机文件;
(2)计算机控制转台转动角度读取下一幅图像。
6、按照权利要求5所说的固定式三维光子存储方法,其特征在于所说的绿光的波长为532nm。
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US09/875,947 US6738337B2 (en) | 2000-07-20 | 2001-06-08 | Only-readable three-dimensional optical storage device |
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CN1809877B (zh) * | 2003-05-15 | 2010-05-12 | 汤姆森特许公司 | 高数据密度体全息数据存储方法和系统 |
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GB0121308D0 (en) | 2001-09-03 | 2001-10-24 | Thomas Swan & Company Ltd | Optical processing |
JP4631439B2 (ja) * | 2005-01-06 | 2011-02-16 | ソニー株式会社 | ホログラム記録再生装置およびホログラム記録再生方法 |
GB2504970A (en) | 2012-08-15 | 2014-02-19 | Swan Thomas & Co Ltd | Optical device and methods to reduce cross-talk |
CN103064275B (zh) * | 2013-01-17 | 2016-08-24 | 京东方科技集团股份有限公司 | 全息3d实现装置及方法 |
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US5943145A (en) * | 1995-05-05 | 1999-08-24 | Lucent Technologies Inc. | Phase distance multiplex holography |
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CN1809877B (zh) * | 2003-05-15 | 2010-05-12 | 汤姆森特许公司 | 高数据密度体全息数据存储方法和系统 |
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US20020018429A1 (en) | 2002-02-14 |
US6738337B2 (en) | 2004-05-18 |
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