Laser pulse generated by phase modulation with certain spectrum distribution can suppress buildup of stimulated Brioullin scattering in large aperture laser optics and smooth the speckle pattern illuminating the target by spectral smoothing dispersion, but spectral distortion happening during the pulse transmission and amplification in each system of the laser facility can induce FM-to-AM effect, which will seriously affect the performance of the laser facility and physics experiments. The principal of phase modulated pulse, the reason why FM-to-AM effect happened and the factors which induced the FM-to-AM effect are introduced. And also the progress on suppression of FM-to-AM effect in National Ignition Facility, Laser Mégajoule laser megaioule facility and SG-Ⅲ laser facility are reviewed.