基于LiNbO_3晶体的透射式共光轴体全息存储技术  

Transmission Type of Collinear Volume Holographic Storage Technology Based on LiNbO_3 Crystal

作　　者：李建华[1] 曹良才[1] 谭小地[1] 何庆声[1] 金国藩[1] 

机构地区：[1]清华大学精密测试技术及仪器国家重点实验室,北京100084

出　　处：《光学学报》2012年第4期76-82,共7页Acta Optica Sinica

基　　金：国家973计划(2009CB72400703);国家自然科学基金(60807005;61177001)资助课题

摘　　要：共光轴体全息存储是体全息存储技术实用化的一个发展方向。为了选择合适的参数以搭建基于晶体的透射式共光轴体全息存储系统,对该系统的存储容量、串扰特性和晶体在共光轴存储结构中的存储特性等进行了研究。从理论上分析了共光轴体全息存储系统的存储密度、物镜的参数、空间光调制器的像素尺寸、有效像素数目和移位复用间隔等之间的关系,给出了点扩展函数表达式的物理解释,并根据点扩展函数分析了系统的串扰特性,优化了存储偏振光方向以使晶体表现出最大的动态范围。根据分析优化结果搭建了基于LiNbO3晶体的透射式共光轴体全息存储实验系统,实现了高分辨图像的记录与再现。与传统的双轴系统相比,所搭建的共光轴系统具有光路结构紧凑的特点。Collinear（Coaxial） volume holographic data storage（CVHDS） is one of the promising technologies for the commercialization of the volume holographic data storage.In order to optimize the parameters for the construction of transmission type of CVHDS system,some CVHDS properties such as storage density,crosstalk characteristics and crystal storage property are investigated.The relation between the storage density of CVHDS and the parameters of objective lens,the pixel pitch of the spatial light modulator（SLM）,the effective pixel number of the SLM and the shift pitch for multiplexing are theoretically derived.The physical interpretation for the expression of the point spread function is proposed.The crosstalk property is analyzed for different reference patterns based on point spread function.Then the polarization state in the photorefractive crystal is optimized for as larger dynamic range as possible.Finally,the transmission type of CVHDS system based on LiNbO3 crystal is constructed for the data-storage experimental test.Data-storage experimental results indicate that pictures with high resolution can be recorded and reconstructed with high fidelity by this system.Compared with the two-axis geometry,the optical setup of the CVHDS system is more concise and smaller in size.

关 键 词：全息 共光轴系统 透射式结构 数据存储 LINBO3晶体 

分 类 号：O438.1[机械工程—光学工程]