Abstract: A specimen holder for a high-pressure freezing device comprises a first shaped part (2) and a second shaped part (3) that form, in the mutually joined state, a specimen space (6). The first shaped part (2) is embodied in a cup shape, and possesses a bottom (5) that closes off the specimen chamber (6) toward the outside to prevent contact between the specimen and a pressure medium.

Abstract: A specimen holder for a high-pressure freezing device comprises a first shaped part (2) and a second shaped part (3) that form, in the mutually joined state, a specimen space (6). The first shaped part (2) is embodied in a cup shape, and possesses a bottom (5) that closes off the specimen chamber (6) toward the outside to prevent contact between the specimen and a pressure medium.

Abstract: A microscope with continuously or discontinuously variable objective magnification is provided with an autofocus system whose beam path passes through the objective and is directed out of the imaging beam path of the microscope between objective and eye piece to at least one photo-electric detector means. At least one optical system is located or locatable in the beam path of the autofocus system which allows or causes the at least one image formed on the detector means to be altered in scale when a change in the objective magnification occurs. The at least one optical system can be a zoom system or a series of lenses or fixed lens systems arranged to be inserted into the beam path of the focusing system. When the objective or objective magnification is changed, a coupling mechanism serves to appropriately vary the focal length of the at least one optical system located or locatable in the beam path of the autofocus system.

Abstract: A microscope with continuously or discontinuously variable objective magnification is provided with an autofocus system, the beam path of which passes through the objective and is directed out of the imaging beam path of the microscope between objective and eyepiece to at least one photo-electric detector means. At least one optical system is located or locatable in the beam path of the autofocus system which allows or causes the at least one image formed on the detector means to be altered in scale when a change in the objective magnification occurs. The at least one optical system may be a zoom system or a series of lenses or fixed lens systems arranged to be moved into the beam path of the focusing system. By a coupling mechanism, it is achieved that, upon an exchange of the objective or a change in the objective magnification, the focal length of the at least one optical system located or locatable in the beam path of the autofocus system is varied accordingly.

Abstract: In a microscope with a motor-driven objective turret, an intermediate position is provided between each two adjacent primary turret positions. This intermediate position enables manual operations to be carried out on the objectives in the objective turret, in a convenient manner, before viewing. Automatic means are provided for switching off the motor in both the primary and the intermediate turret positions.