High bandwidth electro-optic scanner for optical data storage

Beam deflectors can be used as fine tracking actuators to improve track acc ess time and data rate in future high performance optical disk drives. In t his paper we report on the use of an electro-optic (EO) scanner for optical data storage. Track following has been accomplished using this EO actuator with a servo bandwidth of 200 kHz, and single-stage high-speed track switc hing/following has been demonstrated in a new optical head tracking system with reduced offset. A fine tracking experiment has also been demonstrated using an EO actuator with a voice coil motor (VCM) actuator to extend the f ine tracking range. A new compensator design method, the PQ method, has bee n used for this scanner/VCM compound actuator system. Significant improveme nts in track switching/following speed are demonstrated with the scanner/VC M compound actuator as compared to tracking with the VCM actuator alone.