Integrated micro optical flying head with lens positioning actuator for small form factor data storage

Abstract

An integrated MEMS optical flying head(OFH) is presented for a small form factor with high-density portable data storage. It is composed of a high numerical-aperture(NA) objective lens, a micro lens actuator for adjusting the position of the lens, an integrated air-bearing-slider(ABS), and an embedded magnetic-field-modulation(MFM) coil for magneto-optical recording. For adjusting the optimal focal length of the lens, a vertical comb-driven actuator and a parallel plate actuator are adopted. In addition, the area-optimized torsion spring is used for vertical actuation. The ABS structure and the double layer MFM coil are fabricated on a transparent substrate bonded to the silicon actuator. The overall size of the integrated MEMS OFH assembled with the high NA(0.85) objective lens is 3 mm? 1.6 mm? 0.5 mm(in length? width? thickness), which makes it suitable for a portable optical storage device.