Focusing Actuator for Magneto-optical Disk Drives
Junichi Ichihara, Koichi Tezuka and Akihiko Makita
Atsugi Laboratory, Fujitsu Laboratories, Ltd., 10-1, Morinosato Wakamiya, Atsugi, Kanagawa 243-01, Japan
Magneto-optical disk drives have some disadvantages compared with hard disk drives such as low access speed and low data rate. A small-light optical head and high speed rotation of the drive would improve the performance , as well as achieving over write. This paper details the development of a small-light focusing actuator, which can be used in high speed rotation of disks and make optical heads small and thin. It discusses the actuator suspension which raises the frequencies of higher order mechanical resonance. It also includes a parallel leaf spring suspension with the visco-elastic damping layer. It experimentally evaluates the vibration characteristics. Results show that the frequencies of higher order mechanical resonance are above 50kHz. The actuator is driven by a novel moving coil motor which makes the moving part thin and stiff. This paper describes the design and performance of the motor.