The resonance - enhanced multi - photon ionization ( rempi ) spectrum of no in the region of 420 - 680nm is obtained by using optical parameter generator and amplifier ( opg / opa ) as radiation source . the opg / opa was pumped by nd : yag ( quantel ) laser 本工作以超短脉冲( 35ps ) nd : yag激光的三倍频输出( 355nm )泵浦光学参量发生放大器作为激发源,获得了no分子在420 680nm波长范围内的多光子共振离化光谱。