从理论上提出了光折变材料中光电导过程的陷阱作用机制，给出了载流子的光激发、复合及俘获过程的动力学方程，得到了陷阱作用下的光生量子效率的解析表达式。实验上，对掺杂不同浓度的C60（C70）的PVK薄膜的光生载流子量子效率随光强的变化关系进行了测量，得到了与理论预测相一致的结果。 The mechanism of photon conduction traps in photorefractive materials is theoretically proposed. The kinetic equations of photon excitation, recombination and trapping of carriers are given. The analytical expression of quantum yield of light generated by traps is obtained . Experimentally, the photon-carrier quantum efficiency of PVK films doped with different concentrations of C60 (C70) was measured as a function of light intensity, and the results consistent with theoretical predictions were obtained.