Development of the core technologies for large-scale 3D-MEMS optical switches

MEMS optical switches have been given attention as a key fabric for large-scale optical switches because of their potentially compact and low-cost features. The main components of the switch are MEMS mirror array and an optical fiber collimator array. MEMS mirror array can directly handle multi-channel optical signals from fiber to fiber without converting them to electric signals, which enables us to realize all-optical, free-space cross-connection. The MEMS mirror developed by NTT, which is made of single-crystal silicon, has the flatness of optical quality and a durable mechanical structure. The mirror also has a unique terrace-shape driving electrode to make it tilt at low-driving voltage. Optical fiber collimator array is another key component for MEMS optical switch. We propose a novel way to make a low-cost and high-accuracy optical fiber collimator array. This paper demonstrates the characteristics of the two main components mentioned above which constitute the free-space optical switch module.