Study of the Image Quality based on MTF in Volume Hologram Storage System

摘要

The combination of excellent linear, nonlinear properties and good mass productivity of lithium niobate (LiNbO_3) single crystals has made them important for extensive industrial applications. However, when LiNbO_3 devices, such as frequency doubling converters, waveguide lasers, optical switches, and parametric oscillators, are operated at a high laser intensity, their optical performance is severely restricted by the laser-induced refractive index inhomogeneity, which has been labeled "optical damage" or "photorefraction". Especially, when LiNbO_3 crystals are used as holographic storage media, higher light-induced scattering resistance ability can improve the quality of the storage information, suppress the generation of noise, and reduce the bit error rate. There are many factors to influence the bit error rate of read-out image in holographic storage. Above all, SLM and CCD play the key role as well as the signal matching between these devices. In this paper, the output response of CCD to the periodic pixel distribution of SLM is analyzed based on the modulation transfer function theory and numerical simulation method. The influence of fill-factor, contrast and phase matching between CCD and SLM on bit error rate are also studied. Finally, the computer simulation result on bit error is given in this paper.