MEMS technology in optical switching

All-optical switching fabrics based on the Micro-Electro-Mechanical Systems (MEMS) technology are now widely available on the market. This paper reviews working principles and architectures of MEMS-based optical switches from the past to the present day. During the last two decades, many approaches and actuating mechanisms emerged. In general, optical MEMS-based switches can employ movable micromirrors as basic switching element, or movable couplers (resonators). The switching speed can vary from less than to tens of ms. This paper briefly describes principles of all of these switches. Optical properties (insertion loss, crosstalk) and switching speed are also discussed.