Miniaturized fiber optical switches with nonmoving polymeric mirrors for teleand data-communication networks fabricated using the LIGA technology

摘要

Abstract: Fiber optical switches for telecom and datacom purposes become more and more important with the growth of fiber- based networks. This paper proposes a new principle for manipulating optical light paths through switchable, but non-moving polymeric mirrors in free-space optical interconnects. To achieve this a polymeric body and a thin liquid film are moved within a cavity. By moving the body up and down perpendicular to the light path the cavity wall can be switched from total reflective to transmissive state while the liquid film remains between body and wall due to capillary forces. The body can be moved with integrated electro-magnetic actuators and so the whole concept allows the realization of very compact switching elements. The coupling of single mode optical fibers requires a lateral and angular alignment precision in the micron and millirad range for both direct coupling and expanded beam coupling concepts. To meet these requirements, the LIGA technology provides a promising approach with respect to the high precision and also low-cost fabrication by mass replication processes. The combination of LIGA technology with other precision machining technologies allows the fabrication of miniaturized systems with both micro-optic and micromechanic components which fulfill the required tolerances for optical coupling. First demonstrators of 1 $MUL 2 and 2 $MUL 2 switches with bistable electro-magnetic actuators have been fabricated to show the feasibility of the proposed principle. The measured insertion loss is less than 2 dB at 1300 nm with $MIN@40 dB crosstalk. The switching time was measured 100 ms. The capabilities of the proposed non-moving mirror principle can be applied to 1 $MUL 2 repair switches for the access area as well as to FDDI-switching-nodes up to compact N $MUL M cross-connect switches for reconfiguration purposes or parallel interconnects to optical backplanes for the office area.!11