Abstract: An objective changer for a telescope-type stereomicroscope which has two telescope systems whose entrance-side beam paths are oriented parallel to one another, which includes a carrier and an objective holder which is held at the carrier so as to be movable relative to the carrier between a first stereoscopic working position and a second stereoscopic working position and a third working position. The objective holder has at least a first and a second receptacle for stereo objectives and a third receptacle for an additional objective. The two telescope system beam paths penetrate one of the receptacles for the stereo objectives at least in the stereoscopic working positions when the objective changer is arranged at the stereomicroscope.

Abstract: An objective changer for a telescope-type stereomicroscope which has two telescope systems whose entrance-side beam paths are oriented parallel to one another comprises a carrier and an objective holder which is held at the carrier so as to be movable relative to the carrier between a first stereoscopic working position and a second stereoscopic working position and a third working position. The objective holder has at least a first and a second receptacle for stereo objectives and a third receptacle for an additional objective. The two telescope system beam paths penetrate one of the receptacles for the stereo objectives at least in the stereoscopic working positions when the objective changer is arranged at the stereomicroscope.

Abstract: The invention is directed to an afocal zoom system, particularly for use in microscopes, comprising at least four optical assemblies, two of which assemblies are movable relative to one another and to the rest of the assemblies for the purpose of changing the magnification. It is the object of the invention to develop an afocal zoom system which enables a relatively small structural size for a microscope also in combination with a suitable drive mechanism. This object is met by an afocal zoom system of the type described above in which every adjustable magnification can be achieved by a displacing movement of the two movable optical assemblies in the same direction.

Abstract: The invention is directed to a device for switching a swivelable holder between two positions, e.g., for switching microscope objectives. The actuating element and swivelable holder are connected by two stretchable connection elements which serve to transmit the rotational movement and to fix the swivelable holder in the switching positions.

Abstract: The invention is directed to a device for switching a swivelable holder between two positions, e.g., for switching microscope objectives. The actuating element and swivelable holder are connected by two stretchable connection elements which serve to transmit the rotational movement and to fix the swivelable holder in the switching positions.

Abstract: The invention is directed to an afocal zoom system, particularly for use in microscopes, comprising at least four optical assemblies, two of which assemblies are movable relative to one another and to the rest of the assemblies for the purpose of changing the magnification. It is the object of the invention to develop an afocal zoom system which enables a relatively small structural size for a microscope also in combination with a suitable drive mechanism. This object is met by an afocal zoom system of the type described above in which every adjustable magnification can be achieved by a displacing movement of the two movable optical assemblies in the same direction.

Abstract: A variable objective is disclosed with finite transmission length L from the object plane 0 to the image plane 0′, comprising three axially displaceable lens groups, wherein, successively in the imaging direction, a first lens group has positive refractive power, a second lens group has negative refractive power and the third lens group has positive refractive power. In a variable objective of the type mentioned above, the first lens group and third lens group are displaceable jointly while maintaining the same relative distance L2, wherein the distance L1+D1actual measured between the first lens group and the object plane 0 changes by the amount D1actual=0 . . . D1max, while the distance D2actual between the second lens group and the object plane 0 is subjected to a positively-guided nonlinear change.