A high fill factor linear mirror array for a wavelength selective switch

Abstract

Optical networks require optical switching systems with high linear fill factor mirror arrays for wavelength add/drop nodes. The mirrors presented here use coils attached to the mirrors interacting with the field from a permanent magnet array. Results of magnetic and mechanical FEA modeling are presented. Fill factors in excess of 90% were achieved, and mirror rotation in excess of 5° (mechanical angle) with less than 10 mA current was demonstrated. Mirrors operated in excess of 2.8 billion cycles with no fatigue or failures.

Optical MEMS for Lightwave Communication

“…Several types of WSS micromirror arrays have been reported, including electrostatic [83], [84] and electromagnetic [85] actuations. The key parameters are large continuous scan angle and high fill factor, with the mirror size and pitch matching those of the optical system.…”

Solution hardened platinum alloy flexure materials for improved performance and reliability of MEMS devices

“…While hysteresis can be indicative of plastic behavior of the flexure, fatigue and creep are also important issues when considering material behavior in metal flexures. We have previously reported that angle versus current performance of a mirror built using this flexure material is linear [18][19][20]. The very small level of hysteresis indicates that dislocation movement is greatly reduced in these alloys, allowing precise and repeatable actuation.…”

“…Platinum alloy flexures were used to support electromagnetically actuated micromirrors used for optical switching [18][19][20]. Figure 5 provides an example of the fabrication process used to realize these micromirror devices [19].…”

Design and fabrication of a high fill-factor micro-mirror array

“…Among all the actuation mechanisms, electrostatic actuation has been one of the most popular approaches for driving MEMS devices. Now, several electrostatic actuated micromirror arrays with a traditional design has been reported [5][6][7], in which movable mirror plates are built with fixed parallelplate electrodes on an insulation layer. An intrinsic characteristic of this structure is that it needs a high driving voltage to obtain a large tilted angle.…”