Abstract
We have developed and demonstrated a novel non-contact deformable mirror actuator for spherical aberration compensation. It consists primarily of two components: a mirror element and an electromagnet. A magnetic ring with low stiffness placed on a mirror deformed the mirror into an ideal parabolic shape by applying a magnetic force generated from an electromagnet underneath. We developed the fabrication process of the mirror element consisting of polydimethylsiloxane (PDMS) and a silicon-on-insulator (SOI) substrate. Moreover, we fabricated and evaluated the performance of the deformable mirror that had an effective diameter of 4 mm. A maximum 6.5-μm mirror deformation could be achieved. Moreover, the focal length could be controlled from 1.8×10^<-3> m to 24 m by changing the applied current. These results show the deformable mirror actuator can compensate the spherical aberration for the four recording layers of an optical disc.
