Patent ID: 7441445

Claim:
A surface information measuring apparatus which is a surface information measuring apparatus for measuring shape information of a sample surface or physical information of a sample by making a stylus proximate to or brought into contact with the sample surface, said surface information measuring apparatus comprising: a probe having the stylus at a front end thereof and arranged on an upper side of the sample; a Z actuator fixed with the probe at a front end thereof for making the probe proximate to or remote from the sample surface by being elongated or contracted in a Z direction orthogonal to the sample surface when the Z actuator is applied with a voltage; applying means for applying the voltage to the Z actuator; and controlling means for controlling to operate the applying means; wherein the Z actuator includes a piezoelectric member having a section in a cylindrical shape and formed by being elongated in the Z direction and capable of being elongated or contracted in the Z direction, and a plurality of divided electrodes provided to be respectively electrically independent from each other in a state of being divided by at least 3 or more in a peripheral direction at an inner peripheral face or an outer peripheral face of the piezoelectric member for applying the voltages to elongate or contract the piezoelectric member in the Z direction within ranges of regions brought into contact therewith; wherein the applying means are made to be able to apply simultaneously the voltages of amounts respectively different from each other to the plurality of divided electrodes; and wherein the controlling means controls the applying means to apply the voltages by previously determined rates of voltage applying amounts such that elongating or contracting amounts of respective contact regions of the piezoelectric member respectively brought into contact with the plurality of divided electrodes respectively become the same.