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报道了对光辐照YBa_2Cu_3O_6.92材料的正电子寿命谱研究结果，给出了正电子寿命参数随辐照时间变化的基本特征，利用两态捕获模型对实验结果进行了初步分析，计算了局域电子密度尼和空位浓度已随辐照时间的变化，发现光诱导而产生Cu－O链区域电子结构的变化，证明O（1）和0（5）位之间的氧迁移和重新分布使得氧有序乃是光诱导电性的主要原因，为YBa_2Cu_3O_6.92体系光电导机理的理解提供了重要的正电子实验证据。
The research results of positron lifetime spectra of YBa_2Cu_3O_6.92 material irradiated by light are reported. The basic characteristics of the positron lifetime parameters with the change of irradiation time are given. The experimental results are preliminarily analyzed by using the two-state capture model. The electron density and the vacancy concentration of the domains have been changed with the irradiation time, and it was found that the light-induced changes in the electronic structure of the Cu-O chain region proves that oxygen migration and redistribution between O (1) and 0 (5) Oxygen order is the main reason of photoinduced electrical conductivity and provides important positron experimental evidence for the understanding of photoconductivity mechanism of YBa_2Cu_3O_6.92 system.