Free-space fiber-optic switches based on MEMS vertical torsion mirrors

This paper reports on the design, fabrication, and performance of a novel M EMS (micro-electro-mechanical-system) fiber-optic switch based on surface-m icromachined vertical torsion mirrors. The vertical torsion mirror itself c an be used as a 1 x 2 or an ON-OFF switch. A 2 x 2 MEMS fiber-optic switch with four vertical torsion mirrors has also been fabricated. The switching voltage is measured to be 80 V for switching angles of 45 degrees. We have achieved a switching time of less than 400 mu s (fall time) and an optical insertion loss of 1.25 dB for single-mode fibers. In addition, a bulk-micro machined silicon submount has been developed to package the switch with mic roball lenses and multimode fibers with passive alignment. With the microma chined switch chip and the hybrid-packaging scheme, the size, weight, and p otentially the cost of the fiber-optic switches can be dramatically reduced .