<p>We present a comprehensive numerical investigation of temporal interference phenomena in the nonlinear propagation of triangular optical pulses through dispersive nonlinear fibers. The pulse dynamics are modeled using the generalized nonlinear Schrödinger equation, incorporating group-velocity dispersion, third-order dispersion, self-phase modulation, and the delayed Raman response. Owing to the inclusion of third-order dispersion, initially symmetric triangular pulses with a linear intensity profile develop asymmetric temporal profiles during propagation. We demonstrate that the interplay of nonlinear phase modulation and dispersion gives rise to controlled temporal interference patterns, a time-domain analogue of spatial diffraction, where the input pulse width functions as an effective “temporal aperture.” By tuning pulse width and separation, we achieve deliberate manipulation of interference fringes and spectral modulations, enabling engineering of pulse coherence and temporal structure. Under appropriate dispersion-nonlinearity balance, triangular pulses exhibit soliton-like reshaping and stability. Quantitative analysis of broadening, asymmetry, and bit-error-rate evolution confirms that shorter pulses are very sensitive to nonlinear distortions, whereas broader pulses maintain coherence over longer distances. These results establish triangular pulses as versatile testbeds for shape-dependent nonlinear dynamics and provide guidelines for dispersion-managed pulse shaping, ultrafast communications, and waveform synthesis.</p>