傅里叶极限分辨率的激光线宽测量

Laser Linewidth Measurement at Fourier Limit Resolution

提出了一种基于时间分辨及傅里叶变换测量激光线宽的方法,其分辨率仅受限于傅里叶极限。在实验上通过时间分辨方法测量了半导体激光器和光纤激光器的线宽,并与射频频谱分析的方法进行比较。对两种激光器在不同积分时间内进行线宽测量,结果证明这种傅里叶极限线宽测量的方法相比于射频频谱分析的方法具有更小的测量误差,通过时间分辨方法获取频谱信息具有实时采集的优势。

A method for measuring laser linewidth at Fourier limit based on time resolution and Fourier transform is proposed,whose resolution is limited by Fourier transform.In experiments,the linewidths of a fiber laser and a semiconductor laser are measured by the time-resolved method,which are compared with those by the traditional radio frequency(RF)spectral methods.The linewidth measurement results of these two lasers under different integration time show that the proposed measurement method at Fourier limit has smaller measurement errors than those by the RF spectral analyzer.Moreover,the acquisition of spectral information by the time-resolved method has the advantage of real-time acquisition.