Gimbaled scanning micro-mirror actuation scheme and architecture

A micro-electro-mechanical system device for actuating a gimbaled element, the device comprising:

• (a) an electromagnetic actuator for actuating a first angular degree of freedom (DOF) of rotation about the vertical axis;
• and
• (b) an electrostatic actuator for actuating a second angular DOF of rotation about the horizontal axis, wherein said horizontal axis and said vertical axis are orthogonal and coplanar,
• wherein the horizontal axis comprises an internal axis driven electrostatically and the vertical axis comprises an external axis driven electromagnetically,
• wherein said electromagnetic actuator comprises:
• (a) external fixed electromagnet coils;
• and
• (b) internal rotating magnets, thereby to define an electromagnetic subsystem,
• and wherein the electromagnetic subsystem includes an electro-magnetic circuit, a ferromagnetic material, said coils, and said magnets, and is symmetrically located around the vertical axis, such that the electro-magnetic circuit, the ferromagnetic material, the coils, and the magnets each encompass the vertical axis.

A method for using a micro-electro-mechanical system device to actuate a gimbaled element, the method comprising:

• (a) using an electromagnetic actuator for actuating a first angular degree of freedom (DOF) of rotation about the vertical axis;
• and
• (b) using an electrostatic actuator for actuating a second angular DOF of rotation about the horizontal axis, wherein said horizontal axis and said vertical axis are orthogonal and coplanar,
• wherein the horizontal axis comprises an internal axis driven electrostatically and the vertical axis comprises an external axis driven electromagnetically, and
• also comprising providing an electromagnetic actuator with a symmetric structure, which is symmetric with respect to the horizontal plane, thereby to define a plane of symmetry, and with respect to the vertical z axis, thereby to define an axis of symmetry, and which is operative for actuating forces produced by said electromagnetic actuator, to create only a rotational movement of said first DOF about said vertical axis, wherein the electromagnetic actuator's symmetric structure includes two pairs of magnet-assemblies, each individual pair from among said pairs comprising two magnets arranged symmetrically about the vertical axis and engaging top and bottom ends thereof.