Abstract: A transducer in an imaging optical system for generating optical contrasts in the near-field representation of topographies of an object by outcoupling evanescent waves from the underside of the transducer. The transducer comprises a substrate having a transparent plane-parallel protuberance corresponding to the field size of the imaging optical system and pointing toward the object. The specimen outcouples evanescent waves from an underside of the transducer, where the transducer underside is arranged in a focal plane of the imaging optical system.

Abstract: A microscope with a Kohler illumination device having an at least approximately infinite beam (17) is described. An optical slit (6) is provided in the field diaphragm plane (LF) which is followed by an optical transmission grating (12) in the infinite (17). The resulting zero-order and first-order diffraction images are imaged either simultaneously or one after the other on a sensor (13). The spectral and densitometric distribution in a preselected object (10a) is determined by means of evaluation devices connected after the sensor (13). It is thereby possible, for example, to determine simultaneously the width of an object by means of the densitometric distribution and the height of an object by means of the spectral distribution.

Abstract: An apparatus for producing an optical image contrast which may be used in a microscope is disclosed. Specifically, the apparatus is based on the Moire effect and uses two screens or gratings which are rotated simultaneously at different angular velocities in order to increase the depth of focus and resolution achievable with conventional systems.

Abstract: An optical component is described which can be introduced into a finite or an infinite beam path and which is provided with a spectrally selective filtering characteristic and thus as the same time compensates the thereby generated geometric-optical negative influence by appropriate image-relevant compensation measures. The optical component exhibits at least one optically effective, non-planar surface. It has, for example, the property of completely absorbing visible light and of being completely transparent to shorter- or longer-wavelength light. In addition to this, a laser autofocus arrangement known per se is described, which is equipped with the optical component according to the invention, whereby a dark field illumination with an incident light microscope can be achieved while maintaining the autofocus function.

Abstract: An automatic focusing apparatus for optical instruments, in particular for reflected light microscopes, wherein a measuring point is produced on the surface of an object by an eccentric measuring beam formed by blocking a portion of the path of a full beam. The measuring point is imaged onto a photoelectric device by reflecting the measuring beam along the blocked out path. When the object plane wanders from the focal plane, the photoelectric device actuates a control device which returns the object plane to the focal plane. The apparatus comprises a source of light to produce a, preferably pulsed, laser light for the full measuring beam, an optical structural element for geometrically blocking one-half of the full measuring beam to produce the eccentric measuring beam and simultaneously for geometrically blocking the reflected measuring beam from the path of the full measuring beam.