Abstract: A probe needle is successively moved to a plurality of measurement points set in a measurement region on a sample so as to measure a z-displacement amount. An excitation control unit feedback-controls a piezoelectric element so that a vibration amplitude of a cantilever is constant in accordance with the detection output by a displacement detection unit. Moreover, a vertical displacement control unit feedback-controls a vertical position scan unit so as to obtain a constant distance between the probe needle and the sample according to a frequency shift by a frequency detection unit. When changes of outputs of two feedback loops at a certain measurement point are both within a predetermined range, a main control unit issues an instruction to a horizontal position control unit to rapidly move to the next measurement point. As a result, it is possible to adaptively decide such a measurement time that both of the two feedback controls at respective measurement points are established.

Abstract: A probe needle is successively moved to a plurality of measurement points set in a measurement region on a sample so as to measure a z-displacement amount. An excitation control unit feedback-controls a piezoelectric element so that a vibration amplitude of a cantilever is constant in accordance with the detection output by a displacement detection unit. Moreover, a vertical displacement control unit feedback-controls a vertical position scan unit so as to obtain a constant distance between the probe needle and the sample according to a frequency shift by a frequency detection unit. When changes of outputs of two feedback loops at a certain measurement point are both within a predetermined range, a main control unit issues an instruction to a horizontal position control unit to rapidly move to the next measurement point. As a result, it is possible to adaptively decide such a measurement time that both of the two feedback controls at respective measurement points are established.