Superior Accuracy With Direct-Metrology Capacitive Sensors
Capacitive position feedback is used in the top-of-the-line model. PI’s proprietary capacitive sensors measure position directly and without physical contact. They are free of friction and hysteresis, a fact which, in combination with the positioning resolution of well under 1 nm, makes it possible to achieve very high levels of linearity. A further advantage of direct metrology with capacitive sensors is the high phase fidelity and the high bandwidth of up to 10 kHz.
Alternatively compact, more cost-efficient strain gauge sensors (SGS) featuring nanometer resolution are implemented. Absolute-measuring SGS-sensors are applied to appropriate places on the drive train and thus measure the displacement of the moving part of the stage relative to the base.