Miniaturized Optical Displacement Sensor Assembly Design

We studied a two-input, two-output control system for an HDD requires a sensor to measure displacement between a VCM and a second-stage actuator We thus considered a displacement sensor using the optical lever method. To realize the displacement sensor, an LD and a PD were assembled to the head arm The fabricated sensor showed resolution of 15 nm and bandwidth of 30 kHz From these experimental results, we confirmed that it is possible to realize a measurement system that can detect accurately displacements in a hard disk enclosure.