Abstract: The invention is directed to an arrangement for autofocusing onto a measuring location on an object moving in a direction which is at least approximately vertical to the optical axis of the imaging optics. According to the invention, a diaphragm device is to be provided the diaphragm opening of which extends in a direction aligned with the direction of movement of the measuring location; a receiving device for the measuring light has receiving areas arranged in a row beside each other and is inclined relative to the optical axis so that the image from the diaphragm device is incident on the receiving areas at an inclination of an angle &agr;; wherein the receiving device and the diaphragm opening are positioned relative to each other in such a way that characteristic measuring values are measured on the receiving areas when the measuring location is in or near the focus position.

Abstract: Displaceable optics in microscope illumination, particularly a displaceable collector, comprising an outer guide sleeve and a preferably cylindrical optics housing which slides in the guide sleeve, characterized in that Teflon strips are provided between the optics housing and guide sleeve for flexible centering of the optics.