Method for automatically determining the focusing of a geometrical figure imaged by a focusing optical system

摘要

Method for automatically determining the focusing of a geometrical figure, preferably a point, imaged by a focusing optical system, the imaging plane lying outside the focal plane of the optical system. An image-processing processor is arranged in the imaging plane. The use of only one optical chain and of a CCD sensor in adjusting the optical system of this optical train is rendered possible by determining for different prescribed focal settings of the optical system the associated magnitudes of the imaged geometrical figure in the imaging plane. The minimum extent of the imaged geometrical figure is determined. The focal setting belonging to the minimum extent of the imaged geometrical figure is determined as the locus of the optimum sharp focus of the imaged geometrical figure. IMAGE