用光干涉理论和傅里叶变换的知识，定性半定量的分析超快激光和激光频率梳，根据多光束干涉的结论分析锁模技术形成超快脉冲激光的原理以及超快激光的时域特性，用傅里级数和傅里叶变换的性质分析超快激光频率梳的物理图像、脉冲激光的时域脉宽与频域带宽的关系、以及时域脉冲间隔与频域频率间隔的关系. 介绍频率梳在光频测量中的应用.

Qualitative and semi - quantitative analysis on the ultrashort pulse laser and optical frequency comb is made using the wave interference theory and Fourier transformation. Based on the known conclusions about the multiple beam interference，we analyze the principle of mode locking technology，the temporal characters of pulse laser. Using the Fourier transformation and Fourier series，we demonstrate the physical image of the optical frequency comb，derive the relation between the pulse length and the spectral bandwidth，the relation between the temporal pulse distance and the spectral frequency interval.