焦深大小将直接影响激光光刻加工的最细线宽和线条的边缘倾角从而影响被加工器件性能．传统的几何光学焦深概念对有光刻胶存在时的激光光刻已不适用．本文导出了会聚的高斯光束用于激光光刻时在光刻胶内的光场近似分布形式，由此可判断出光刻胶对光刻线条的分辨率和焦深的影响，从而提出激光光刻时焦深的新概念和估算 Depth of focus will have a direct impact on the thinnest line width of the laser lithography process and the edge of the line to affect the machined device performance. The traditional concept of geometrical optical depth of focus has not been applied to laser lithography in the presence of photoresists. In this paper, the convergent Gaussian beam is used to approximate the distribution of the light field in the photoresist during laser lithography, and the influence of the photoresist on the resolution and depth of focus of the lithography line can be judged. Engraved deep new concepts and estimates