Method for determining the profile of a material surface by point-by-point scanning according to the auto-focussing principle, and coordinate-measuring device

摘要

The invention relates to a method for determining the profile of a material surface by point-by-point scanning according to the auto-focussing principle and to a coordinate-measuring device. An optical system (16) is located in a contact probe (10) which can move in relation to the material surface. The path of the image rays of said optical system has two optical paths of different lengths. Contrast values are measured at the ends of each of the optical paths. The contact probe (10) is adjusted in terms of its distance from the material surface (14) in such a way that the contrast values are equal. The profile of the material surface (14) is then determined based on the position of the contact probe (10) in relation to the material surface.