Gimbal-Less Two-Axis Electromagnetic Microscanner with Twist Mechanism

We present an electromagnetically driven microscanner based on a gimbal-less twist mechanism. In contrast to conventional microscanners using a gimbal-less leverage mechanism, our device utilizes a gimbal-less twist mechanism to increase the scan angle in optical applications requiring a large scanning mirror. The proposed gimbal-less scanner with twist mechanism increases the scan angle by 1.55 and 1.97 times for the slow and fast axes, respectively, under the same force; 3.64 and 1.97 times for the slow and fast axes, respectively, under the same maximum stress, compared to the gimbal-less leverage mechanism. The scanner with a 3-mm-diameter mirror and a current path composed of a single-turn coil was fabricated, and it showed the maximum scan angle of 5 degrees (quasi-static) and 22 degrees (resonant) for the slow and fast axes, respectively. The experimentally estimated crosstalk was as small as 0.47% and 0.97% for the fast and slow axes affected by the other axes, respectively, which was determined using a newly employed methodology based on fast Fourier transform.