IMPROVED WIDE-RANGE BIMORPH SCANNERS

The kinematics of two types of bimorph frames is analyzed. The displacements of frames using divided electrodes are comparable with those using single electrodes and are free of unwanted movements. A range of +/- 75-mu-m has been obtained with a 2D scanner in the form of a square frame with sides 25 mm long using two-phase operating voltages of +/- 150 V. Using custom-made three electrode bimorphs with sections polarized in opposite directions an electrostatically fully screened design was possible. The lowest eigenfrequencies are about 2.5 kHz.