激光光刻是加工微光学及二元光学掩模的主要手段。光刻的最细线宽对所加工的二元微器件性能起决定作用。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， 由此可判断出能光刻线条的分辨力。若入射高斯光束受到振幅或相位调制时， 胶层内的光强分布将发生变化， 从而影响曝光线条的线宽和质量。计算看出： 当入射光中心环受到遮拦时， 可以得到超过光刻物镜极限分辨的线条宽度（０．６ μｍ ）， 但此时对曝光能量控制要求很高。在激光直接写入系统上的曝光试验结果与理论计算相符。 Laser lithography is a major tool for processing micro-optics and binary optical masks. The thinnest linewidth of lithography plays a decisive role in the performance of the fabricated binary micro-device. In this paper, the convergent Gaussian beam is used to approximate the distribution of the optical field in the photoresist during laser lithography, and the resolving power of lithography lines can be judged. If the incident Gaussian beam amplitude or phase modulation, the light intensity distribution within the plastic layer will change, thus affecting the line width and quality of exposed lines. The calculation shows that when the center ring of the incident light is obscured, the line width (0.6 μm) exceeding the limit resolution of the lithography objective can be obtained, but the exposure energy control is very demanding at this time. The result of the exposure test on the laser direct writing system is in line with the theoretical calculation.