从色散型介质中三次激光模型出发 ,通过泛函导数 ,应用小τ近似计算两维色噪声 ,得到激光场定态强度分布 ,研究了定态强度分布的极值点随抽运参量和强度噪声相关时间的变化情况。应用平移 1 N展开方法 ,得到激光场瞬态解 ,即本征值随抽运参量的变化情况。研究结果表明 ,抽运参量和噪声相关时间是激光系统出现一级相变类比的关键因素 ,相位噪声相关时间对强度谱分布中的线宽影响较大 Starting from the cubic laser model in dispersive media, the two-dimensional color noises are calculated by functional derivative and small τ-approximation to get the steady-state intensity distribution of the laser field. The extreme point of the steady-state intensity distribution is studied with the pumping parameters and the intensity noise Relevant time changes. Applying the translation 1 N expansion method, the transient solution of the laser field is obtained, that is, the variation of the eigenvalue with the pumping parameters. The results show that the pumping parameters and noise-related time are the key factors in the first-order phase transition analogy of the laser system. The phase noise correlation time has a great influence on the linewidth in the intensity spectrum