系统研究了γ射线辐照和电子束轰击着色的氯化钠晶体的光致变色特性及其形成机理。在448 K，着色晶体经几个激光脉冲照射就能有效地产生F→C转换，产生的胶体心尺度随着色剂量增加而增大。在着色氯化钠晶体中观测到吸收带位于625 nm的新的胶体心。在523 K，可有效地产生C→F转换，实现了F和C心的可逆转换，在F带激光照射下，F→C转换主要通过F和F′心光致电离后产生的可动缺陷来实现的，并从机理上提出了简明的物理解释。

The photochromic property and colloidal formation mechanism of the sodium chloride crystal material colored by γ ray irradiation and electron beam bombardment are investigated systematically. The F→C conversion can be created efficiently by irradiating the colored crystals with a few laser pulses at 448 K. The sizes of the produced colloids augment with the increase of the colored doses. A new colloid whose absorption band located at 625 nm is produced and observed for the first time in the colored sodium chloride crystal. The C→F conversion can be carried out efficiently at 532 K, so the reversible conversion from F center to C center is realized. The F→C conversion is realized mainly by means of the agglomerating of mobile defects produced by the photoionization of F and F' centers under the F band laser irradiation. The brief physical interpretation is given on the colloidal formation mechanism.