PIEZOELECTRIC INERTIAL STEPPING MOTOR WITH SPHERICAL ROTOR

A piezoelectric inertial stepping motor for multiple rotations of small optical or mechanical components has been developed. The spherical rotor can be rotated about two or three orthogonal axes. Angular step resolution of 1 arcsec is achieved and the maximum speed lies in the range of degrees per second. The design is compact and eliminates mechanical backlash. Simple electronic control is achieved with only one wire per rotational axis. Low-voltage signals between 15 and 30 V are sufficient for driving the motor. No voltage is necessary for maintaining the rotor in a static position. A first application is described with laser optics as they are used in the detector of a scanning force microscope, offering the advantage of remote controlled adjustment.