Add to ORKGIn this paper simulation results of Fabry-Perot mode-locked lasers are presented that are based on measured modal gain data of InGaAsP quantum well optical amplifiers. Gain spectra were measured for various values of injected current density. The gain spectra were fitted to an analytical formula to describe the spectra using a few parameters. These were used as input parameters in a series of simulations of mode-locked lasers. The performance of three-section passively mode-locked lasers (amplifier, saturable absorber and passive waveguide) was studied for various lengths of the absorber and passive waveguide sections as well as various reflectivity values of the resonator mirrors