Yuji Sakata

Wide bandwidth scanning Kerr microscope based on optical sampling technique using externally triggerable pulse laser diode

We have developed a wide bandwidth scanning Kerr microscope to diagnose HDD heads using an optical sampling technique. By using an externally triggerable pulse diode laser source, the temporal response and frequency dependence of the magnetization behavior can be easily evaluated. The developed system has 5 GHz of the measurement bandwidth and 0.3 μm of the spatial resolution.

Development of an Isolation Table with an Active Vibration Control Mechanism.

Isolation tables are effective in preventing vibration. If objects on a table move, however, the table starts vibrating at a low frequency, with a large displacement due to the force of the impact. Some equipment on an isolation table cannot be kept at a constant distance from equipment on the ground. To overcome this problem, An active vibration control mechanism based on state feedback control using 4 voice-coil motors was developed. This system could suppress the displacement of the isolation table at 100 μm even if some objects on the table moved.