Given that the current research on amplitude-frequency effects is primarily limited to focusing on pulse top modulationfrom a time-domain perspective, which fails to comprehensively reveal its characteristics in the frequency domain or other dimensions, this study commences from a single-frequency laser phase modulation model, combining theoretical simulations and experimental verifications. It investigates the impact of single-order frequency loss, overall frequency loss, and modulation depthchanges on the excitation of amplitude-frequency effects, considering factors such as waveform intensity modulation, excited amplitude modulation signal strength, and spectrum distribution changes. The research results indicate that as the phase-modulatedlaser deviates further from the center position of the filter, the waveform intensity modulation increases accordingly, while the excited modulation signal strength exhibits a trend of first rising and then falling. Compared with single-order frequency loss, theamplitude-frequency effects excited by overall frequency loss mainly concentrate on the fundamental frequency and second harmonic. Additionally, an increase in modulation depth leads to an enhancement in spectral width and an intensification of the excited modulation signal strength.