Based on the theoretical analysis of fiberoptical coupling

the spectral response of fused optical fiber coupler has numerically modeled by simulating the fabricating process of fiber tapers. The influence of different fusion lengths and drawing distances on the spectral response has been analyzed in details. The results indicate that a shorter fusion length leads to a stronger vibration of the curves of normalized power vs. drawing distance and thus a shorter time for reaching a normalized power of 0.5

which results in more envelopes in the curves. Also

a longer drawing distance leads to more envelopes

smaller wavelength intervals and thus a more sensitive spectral response. The validity of the theoretical results has been confirmed by the experiments. This theoretical model is potentially useful for fabricating fused optical fiber couplers.