本文分析了利用强度自相关和干涉自相关信息获取超短光脉冲形状和啁啾特性的方法及其缺陷。提出了一种直接测量超短光脉冲幅度谱和相位谱的原理和测量装置，并对锁模脉冲进行了测量。然后由逆傅里叶变换即可得到脉冲时域特性（脉冲形状和宽度），且由相位谱可得超短脉冲的各阶啁啾系数。 In this paper, the methods and shortcomings of obtaining shape and chirp characteristics of ultrashort optical pulses by using intensity autocorrelation and interference autocorrelation information are analyzed. A principle and measuring device for directly measuring the amplitude and phase spectra of the ultrashort optical pulse are proposed. The mode-locked pulse is measured. Then, the time-domain characteristics (pulse shape and width) of the pulse can be obtained by the inverse Fourier transform, and the chirp coefficients of each order of the ultrashort pulse can be obtained from the phase spectrum.