Patent ID: 7939789

Claim:
A method for reproducibly determining object characteristics, comprising: imaging an object onto a detector using imaging optics and detecting the object thereon; determining a correction function k by positioning a filter in the beam path in front of the detector to determine a defined change to the brightness I impinging on the detector; and applying the correction function k to a brightness measuring result N originally detected by the detector, such, that a corrected brightness measuring result N′ is proportional to a brightness I impinging on the detector; wherein the detector includes a plurality of detector elements; wherein a shading correction is carried out on the individual detector elements; wherein a common non-linearity correction function {tilde over (ƒ)}(N) is applied to all of the detector elements, wherein all the detector elements are corrected individually by subtraction of the black value (b ij ), and in that these values are used to form an average value, so that an average value ( N l ) formed from the corresponding pixel values of the measuring window is provided for a profile channel (l).