The Essential Research Of Holographic Storage Material Based On The PQ-doped PMMA

With the coming of the era of big data, there is a huge demand for long-term preservation of massive data in the field of information. Optical storage with long life and high density will play important roles in it. Holographic storage technology use the principle of holography to record data. The biggest advantage of holographic storage technology is high density. There are many kinds of holographic recording materials, such as silver halide emulsion, dichromate gelatin, photorefractive polymer materials, photochromic materials and photopolymer. Among them, photopolymer material is a kind of ideal holographic storage material. It has attracted much interest due to its advantages, such as low cost, high diffraction efficiency, high sensitivity, large dynamic range, long service life and so on. It was widely used in the research on holographic data storage. In the study of lots of photopolymer, phenanthrenequinone-doped poly(methyl methacrylate) photopolymer(PQ/PMMA) can be prepared simply and easy to be saved. It has good optical properties and inspired the extensive research interest in this field. However, how to improve the refractive index modulation, diffraction efficiency and storage density is important precondition and technical bottleneck to realize holographic data storage.Using the theory of polarization holographic is an important technical way to improve the storage density of optical storage. We can increase the coding efficiency within the page, restrain the reproduced the noises and enhance the storage density by using polarization state as the information which can be modulated. PQ/PMMA photopolymer have nice polarization sensibility and it is a good material for polarization holography. However, polarization holography has not received much attention owing to the lack of a systematic theory. In this thesis, we optimized the synthesis process of PQ/PMMA photopolymer and studied its characteristic of holographic optical response. Based on the tensor theory, the characteristics of recording and reconstruction process in polarization holography and conventional holography have been studied. In order to explore the material properties, we made some exploratory research work in the following aspects:1) We designed the experimental scheme for detecting the photo-induced anisotropy and holographic characteristics of PQ/PMMA, respectively. As it showed a good property for conventional holography, we studied the optical properties for polarization holography based on the tensor theory. Meanwhile, we verified the validness of the tensor theory through these experiments.2) We studied the effect on the optical properties with changing the concentration of PQ in the material. Through related experimental data, we concluded that the diffraction efficiency can be improved with the increasing of the concentration of PQ. The photo-sensitivity can be as well. PQ/PMMA is not only suitable for conventional holography, but also applicable to polarization holography. In addition, thanks to the nice optical properties of PQ/PMMA, it can be applied to holographic data storage as a good recording material.