Application of a multilayered magnetostrictive film to a micromachined 2-D optical scanner

A novel two-dimensional (2-D) optical scanner has been designed, manufactured and characterized. This scanner features a large mirror (8×6 mm) and is therefore suitable for industrial applications where cheap optical sources and lenses are requested. This scanner uses a multilayer film for its actuation. This film is well known for its high magnetostriction. The mechanical design has been optimized using conventional mechanical considerations as well as finite-element simulations. The device has been characterized in two configurations. Depending on the direction of the applied magnetic field, the magnetostrictive properties of the active film or the electromagnetic force are selectively used. Using this last, total optical deflection angles of 32° and 11° for an applied magnetic field of 0.3 mT are obtained. The ratio of the corresponding resonant frequencies is around 4.5, allowing a nice scanning pattern. Compared to our previous prototype on the same project , the mechanical-magnetic sensitivity has been improved by about a factor 24 when the magnetostriction is used, and by about a factor 75 when the electromagnetic force is used.