摘要 |
According to the present invention, a moving element Ai such as an electrostatically driven actuator is displaced by supplying a drive signal thereto. Meanwhile, a displacement sensing section 6 senses its displacement and a calibrating section 15 automatically calibrates the correlation between the drive signal and the displacement, thereby compensating for a variation in the characteristic of the actuator with time and according to the environment. A switching section 7 selectively connects the single displacement sensing section to a plurality of moving elements Ai one after another, thereby cutting down the circuit for displacement sensing.
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