光折变晶体全息存储中散射噪声特性的研究

Study on the Characteristics of Scattering Noise in Photorefractive Holographic Storage

采用信噪比损失系数 (LSNR)深入研究了光折变铌酸锂晶体中散射噪声对全息输入图像像质的影响。对不同掺杂物质、不同掺杂浓度、不同处理方法以及不同记录方式的大量晶体进行了实验研究 ,并重点考察了物光束引起的散射噪声的特性。实验结果表明 ,氧化态晶体的散射噪声的影响小于生长态和还原态晶体 ,反射光路较之透射光路和邻面入射 ( 90°)

The effects of scattering noise on input images for holographic storage in photorefractive lithium niobate crystals have been investigated in detail by means of measurements of loss of signal-to-noise ratio (LSNR). A variety of lithium niobate crystal samples with different dopants, different doping concentrations different annealing after growth, and used for different recording geometries are studied. More attention has been paid to the characteristics of scattering noise resulting from object beams. The experimental results show that the effect of scattering noise in oxidized crystals is less significant than that in reduced or as-grown crystals. Comparing with transmission and 90°C recording geometries, reflection geometry is less subject to the effect of scattering noise.