A system for visualizing a three-dimensional target area of an object with a measuring device which determines a distance of a surgical instrument in a target area with respect to a predetermined structure in the target area, a display unit for representing the views, and a control unit. The control unit controls the display unit such that the display unit is in a first display mode when a determined distance is greater than a predetermined first limit value, and switches from the first display mode into a second display mode when the determined distance changes from being greater than a predetermined second limit value, which is smaller than or equal to the predetermined first limit value, to smaller than the predetermined second limit value.