Measuring device and method that operates according to the basic principles of confocal microscopy

A scanning system for confocal scanning of an object, comprising a light source, imaging optics for focusing light radiated from said light source onto said object to be scanned, further comprising an image detector for detecting light on an object point backscattered from said object and passing through said imaging optics, wherein

• means for varying a length of an optical path positioned between an aperture array and said object, by which means the optical distance of an image plane can be modified in a specific manner,
• means for influencing light characteristics of the light radiated by said light source onto said object and/or the light reflected from said object and impinging on a sensor, in at least one of its characteristics, during an exposure period (tB1) for acquiring an image, and during said exposure period (tB1) a profile holds which states a specific relationship between the characteristic of said light and the optical distance of the image plane from said imaging optics, and
• means for providing a measured value dependent on the properties of the light of the beam path of observation for the exposure period (tB1), a height coordinate (Zs) of said object being reconstructable from the measured value achieved during said exposure period (tB1) and a reference value, and
• means for determining a comparative value on the basis of a second image acquired in a second exposure period (tB2) and a second profile for the relationship between the characteristic of said light and said distance.