Two-dimensional silicon-on-glass actuator combined with a dispensed polymer microlens

Actuators for objective lens positioning are indispensable components for writing and reading data to and from optical storage media. Significant advances in the technical capabilities of microlens actuators for optical heads have been achieved using MEMS technology, enabling miniaturisation and integration of optical data storage systems. In this reported work, a compact silicon-on-glass (SOG) actuator for two-dimensional (2D) positioning of a dispensed polymer microlens is developed by MEMS technology. A wafer-level process for fabrication of the SOG actuator is achieved using anodic bonding, in which a Pyrex wafer was bonded with an ultra-thin silicon wafer. Dispensed polymer microlenses are fabricated and subsequently integrated onto the 2D actuator by an automatic handling system. Typical displacements of about ±28.6 μm in the tracking direction and 3.2 μm in the focusing direction are experimentally characterised. The compact 2D SOG actuator and assembly technology may be particularly useful for expanding the application area for the optical head.