High Speed 2-Axis Rotational MEMS Micromirror

Researchers at MMDL and Ryerson University have developed a high speed two-axis rotational morror driven by repulsive force electrostatic MEMS actuators. The micromirror was fabricated using surface micromachining technology, PolyMUMPs, and can achieve large rotations as well as out-of-plane translational motions. The micromirror can achieve optical rotation angles of up to +/-2.5° in both axes and a translation stroke distance of 86μm.The micromirror was demonstrated by steering a laser beam to generate static images on a wall.

The 2-axis rotational micromirror utilizes the repulsive force electrostatic actuators to achieve high speed rotational motions. The mirror consists of four actuators located orthogonally around a central reflective surface of 1 mm in diameter. The reflective surface is suspended by flexure beams and springs. The micromirror can also exhibit out-of-place translational motion giving an added third degree of freedom.

The micromirror is demonstrated in vector, point-to-point, display applications. A well collimated laser light is bounced off the mirror surface and steered in a high speed pattern to generate an image on a screen or backdrop. The high speed micromirror is capable of producing images over 30 fps with no distortion, generating static images or smooth animations.


MEMS micromirror shown being rotated along a single axis.


Image generation by micromirror. Both static images and animations can be produced.