中文摘要：

建立了阶跃光激励下固体材料温度变化的三维理论模型，用本征函数法求解热传导方程得到了固体中的温度场分布，研究了样品中的温度随时间和空间的变化规律，讨论了材料的光热属性对温度场分布的影响并由此提出一种测量材料热扩散率的方法。

英文摘要：

A three-dimensional theoretical model of the temperature variation in solid materials with the step optical excitation is set up. In order to obtain the explicit expression of the temperature field in solids, the equations of heat conduction is solved by using the eigen-funetion method. The time evolutions and space distributions of the temperature in samples are studied. The influence of the material＇s optical and thermal properties on temperature distribution is discussed and a convenient method is proposed for measuring the thermal diffusivity of solids.