This paper suggests a method for analyzing moving-magnet type actuators for optical pickups. To move the objective lens to the desired position, voice coil actuators use the electromagnetic force, which is the force exerted on a charge moving in a magnetic field. When an electric current passes through a coil, the coil becomes an electromagnet by the solenoid effect. This causes the force between a coil electromagnet and a permanent magnet. The force affects flexible modes of voice coil actuators because it is dynamic force with the frequency same as that of a driving current. Therefore, the analysis, which considers both the electromagnetic force and that between a coil electromagnet and a permanent magnet, is suggested. The moving-magnet-type actuator is fabricated and its dynamic behaviors are measured experimentally to demonstrate and validate the analysis method. As a result, it is verified that the analysis method offers more exact simulations than current methods. Finally, the dynamic behaviors of the moving-magnet-type actuator are improved using the analysis method.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering