In an adjusting device for displacing individual elements (2) of optical systems or of measuring systems in which the element to be displaced is movable on a base (1) along a predetermined direction (x) by means of a piezoelectric actuator arrangement (21, 22) which is supported by the element (2) and which is constructed and controllable in such a way that it exerts shock pulses on the element (2) in order to carry out a stepwise movement of the element (2) on the base (1), the element (2) is arranged in a body (1; 27) which has an open or closed hollow cross section and is supported in a frictional engagement on this body, at least at one location, with the intermediary of a pretensioned spring device (8, 8′).