| The volume holographic storage technique nowadays has aroused scientists' great interest in researching because of some brilliant characters such as high storage density, high redundancy, capable of concurrent content addressing, high data transmission rate, short access time and strong anti-interference ability, which make it has wide application prospect in military, commercial and medical field. But recently, the volume holographic storage system still has some problems in attaining multiple information storage of uniform diffraction efficiency as well as noise reduction etc.This paper analyzes and investigates some main issues of practical process of the volume holographic storage technique. First of all, taking Mg as the dopant, using Czochralski method and by appropriate selection of some parameters of crystal growth technology such as temperature gradient, pulling rate and rotation speed etc, Mg, Fe co-doped lithium niobate crystals were grown. And by polarizing as well as redox processing, the photorefractive crystals with macro-defect-free and good optical homogeneity were gained. Then the paper amends the traditional exposure project of diffraction efficiency uniformity and put forward a more ideal one. The new project not only considers the Erase-effect in volume holographic storage, but also takes the influence, which recording the geometric configuration of optical path when storing may have upon the refractive index demodulation degree of grating, into account. The modified project settles the problem of the traditional way that the prophase stored images may have relatively exorbitant diffraction efficiency, and strictly realizes the uniformity of diffraction efficiency. At last, the paper sets up a volume holographic storage system, realizes storage and reappearance of dozens of hologram images. It also analyzes the image quality of the reappeared hologram images, concludes the reason that affect the quality of output image and puts forward some solutions.
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