| Volume holographic optical storage technology as the most distinctive and the most promising storage technology is the research priorities in the field of optical storage. Niobate crystals with tungsten bronze structure many of which are excellent photorefractive materials. Strontium-calcium-barium niobate crystals ((Ca0.28Ba0.72)χ(Sr0.60B0O.40)1-χNb2O6, abbreviated as CSBN) with a tungsten bronze structure niobate are growth by State Key Laboratory of Crystal Materials of Shandong University. CSBN crystal belongs to tetragonal system, space group P4bm; with a non-center symmetry, similar to the SBN structure. According to subscript x with different values in the general formula CSBN, there are three different types of CSBN crystals, such as CSBN25 (χ=0.25), CSBN50 (x=0.50), CSBN75 (χ=0.75). This thesis research is mainly on CSBN50 crystals.Digital image processing technology forms a new kind of measurement techniques-image measurement technology in the field of precision measurement. Image measurement technology is a new kind of precision measurement technology, with high-resolution, high-speed, dynamic range, informative and automation, and many other advantages. This paper improve the traditional optical holographic storage experimental system, study holographic storage properties used a new type of calcium strontium barium niobate crystals, deal with experimental results combined with the advantages of image measurement technology above-mentioned, and analyze the reasons for the formation of experimental phenomena. The following aspects are including:Firstly, in order to determine the best conditions for holographic storage experiments, holographic storage performance of CSBN50 is measured. With two-wave coupling experimental methods, under certain conditions, diffraction efficiency of CSBN25, CSBN50 crystals are obtained. It is found that when the angle between two beams is about 25°, the diffraction efficiency is almost in the maximum value. Then under the same experimental conditions, the readout diffraction images time-varying are recorded used CSBN50 crystals as storage medium, using image acquisition software. It is found that the readout image is clear, and becomes dark from the center to the edge gradually. According to the analysis of the readout diffraction images, it is obtained that the erasure time of CSBN50 crystal is about 55s. Finally, it is decided that the best angle between object light and reference light is 25°for holographic storage experimental system, including optical design, the coordination of various parts of the system. Improve the traditional volume holographic storage experimental system, optimize the experimental optical path, reduced the cost of the experiment. A set of image storage automatically, real-time reception and real-time processing, extracting image information, highlight the image features, in order to analyze the reasons for the formation of experimental phenomena.Volume holographic storage experiments are accomplished used CSBN50 crystals with the improved experimental systems. Two rather special experimental phenomena are found during the reconstructing accompanying with grating erasure: one is the readout image is gradually erased from center to edge, and the other is that the edge of the readout image appears to be enhanced for a while and then fades until the readout image disappears completely. By building models of the original and readout images, it is considered that the reason for the first phenomenon should be Gaussian laser intensity distribution and the reason for the second phenomenon may be self-pumped phase conjugation.
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