Laser phase modulation method capable of effectively suppressing amplitude frequency effect

The invention discloses a laser phase modulation method capable of effectively suppressing an amplitude frequency effect. The laser phase modulation method comprises the following steps: (a) firstly, inputting single-frequency continuous laser generated by a single-longitudinal-mode laser to an amplitude modulator; (b) secondly, loading a microwave signal source to the amplitude modulator, and performing amplitude modulation on a direct current voltage source; (c) thirdly, inputting single-frequency pulse light output by the amplitude modulator to a phase modulator for spectrum widening; (d) finally, loading modulation of a non-sinusoidal radio frequency signal source to the phase modulator to obtain a Gaussian spectrum light pulse, wherein the non-sinusoidal radio frequency signal source is formed by reshaping a sinusoidal radio frequency signal proportionally. According to the laser phase modulation method capable of effectively suppressing the amplitude frequency effect, provided by the invention, the modulation of the non-sinusoidal radio frequency signal source is loaded to the phase modulator to obtain the Gaussian light pulse, so that the amplitude frequency effect after transmission and amplification can be better suppressed, and the flatness of spectral lines output by a system is greatly improved.