SBN:Cr晶体的光折变四波混频相位共轭特性实验研究

从实验上研究了同成分SBN:Cr晶体在He-Ne激光照射下的四波混频相位共轭特性.首先测量了在不同泵浦光与信号光光强比m及不同光束夹角2θ的情况下,晶体的四波混频相位共轭反射率R随泵浦光强比p的变化关系.其次测量了泵浦光束与信号光束耦合方向对SBN:Cr晶体的四波混频相位共轭特性的影响,并就两种不同掺杂浓度的晶体样品进行了对比,所得实验结果与理论分析基本一致.最后,利用SBN:Cr晶体四波混频相位共轭特性进行了图象畸变消除实验.

EXPERIMENTAL INVESTIGATION OF THE PHASE CONJUGATION BY PHOTOREFRACTIVE FOUR-WAVE MIXING IN SBN:Cr CRYSTALS

It presents the experiment results of the phase conjugation by photorefractive degenerate four wave mixing(DFWM)in congruent SBN:Cr crystals illuminated by He-Ne laser(632.8nm). The dependences of the phase conjugate reflectivity of crystal on pump ratio p are measured under different wave coupling directions, beam ratios m and beam crossing angles 2θ.It is shown that the crystal sample doped with 1000ppm Cr has higher phase conjugate reflectivity than that sample doped with 500ppm Cr.Using wave coupling theory, the experimental results are qualitatively analyzed and essentially explained. The phase conjugator based on photorefractive DFWM can be effectively used to correct the distortion of an image. A primary result is also given in this paper.