Based on Rayleigh-Sommerfeld diffraction formula, the analytical expression of the collimation field of semiconductor laser off-axis beams is derived by the method of stationary phase.

• 根据瑞利索末菲衍射公式,利用稳相法得出了半导体激光器远轴光束经过透镜准直后的场分布解析表达式。