Optimal design of crosstalk in 4×10Gbit/s parallel optical modules

In order to realize crosstalk optimization of 4×10Gbit/s parallel optical modules, by using the ABCD transfer matrix method, combining with the optical fiber coupling constraint and the theory of collimating lens, focus lens and fiber end surface of the ball lens, two sets of optimization schemes were designed. Beam characteristics of vertical cavity surface emitting lasers (VCSEL) were studied, the relationship between the spot radius and divergence angle was simulated by using MATLAB, and crosstalk situation was analyzed. Optical modeling in ZEMAX non-sequential mode was founded, the parameters of lens structure and the design of fiber end face were optimized. After theoretical analysis and experimental verification, the optimized coupling beam radius and coupling efficiency were obtained. The results show that in indirect coupling optimization structure, light spot at the end of fiber is 53.72μm, coupling efficiency is up to 72.59%. In direct coupling optimization structure, light spot at the end of fiber is 3.695μm, and coupling efficiency is up to 76.11%. The design effectively solves the problem of optical crosstalk between parallel optical modules. The study is helpful for the optimization of transmission quality of optical network signal.