Silicon Microlens Surface Mounted on V-groove for Low-cost Optical Modules

摘要

We propose a silicon microlens that is mountable on a silicon v-groove platform for low-cost telecommunication optical modules. The proposed silicon microlens has a rod shape which has the diameter of 125μm, identical to a single-mode fiber. Therefore, it can be passively embedded in the v-groove in conjunction with the optical fiber with high precision. We employed diffractive microlens that can be fabricated on the top surface of the rod by conventional LSI technology. Better coupling efficiency between a laser diode and an optical fiber is expected with silicon diffractive lenses as compared with conventional silica ones. The coupling efficiency of ―0.7 dB between two single-mode fibers was obtained with silicon lenses significantly better than―1.4 dB of insertion loss obtained by a pair of silica diffractive lenses. With good coupling efficiency and the ease of packaging by surface mount technology (SMT), silicon diffractive microlens is promising for low-cost and high-performance optical module applications.