Movement dynamics analysis for an optical pickup head lens actuator in a digital versatile disc system

With the rapid development of CD/DVD (compact disc/digital versatile disc) technology, the disc rotation speed and the information density have increased greatly to fulfil the demand of high information bit rate transfer. As one of the most important elements in a DVD pickup head, objective lens actuators are required to provide a more precise means to accurately follow the disc deviation. The design of the lens actuator becomes all the more important and critical. In order to give complete suggestion to the design of the lens actuator, we put forward the movement differential equations as a new theoretical means to analyse the characteristics of the lens actuator reliably and rigorously. Based on the theoretical analyses, many important and effective methods are proposed. A typical experiment verifies that the performance of our lens actuator head, which adopts these methods, can satisfy the high speed and high density requirement of DVD systems.