Design optimization of an asymmetric optical pickup

An asymmetric actuator can be used to reduce the distance between the reflective mirror and objective lens of a small optical disk drive for use in the notebook-sized personal computer data storage devices. However, this asymmetric actuator is very sensitive to the subsidiary resonance. A main factor causing the subsidiary resonance is found and verified by experimental results. An analytical approach using a simple lumped parameter system model is presented. The main factor causing the subsidiary resonance is significantly reduced by adding upper yoke and further improved by design optimization process.