Abstract: A method for focusing and diopter adjustment in a binocular telescope, in which, for the purpose of diopter adjustment, optical focusing elements (12) in the two telescope tubes (2, 3) can be displaced relative to one another, is distinguished by the fact that, as a result of rotation of a focus drive knob (5), both focusing elements (12) are displaced simultaneously by equal distances via a focus drive, the displacement of at least one of the focusing elements (12) can be locked (13, 14), and, as a result of rotation of the focus drive knob (5), while overcoming a frictional force in the focus drive to the locked focusing element (12), only the unlocked focusing element (12) is displaced.

Abstract: A play-free rotary mounting for a drive roll held on stop surfaces in the axial direction on a cylindrical body, wherein V-shaped annular grooves with an opening angle V are provided at least in one of the end faces of the drive roll and the stop surface located opposite them on the body, V-shaped bearing shells with at approximately identical opening angles and approximately identical leg length are inserted into the annular grooves, the vertex diameters of the annular grooves differ from the vertex diameters of the bearing shells. Balls with a diameter matched to the opening width of the bearing shells are inserted into the bearing shells. At least one of the stop surfaces can be adjusted in the axial direction in order to clamp the drive roll in. Instead of different vertex diameters, different opening angles can also be provided for the annular grooves and opening angles for the bearing shells.

Abstract: A method for focusing and diopter adjustment in a binocular telescope, in which, for the purpose of diopter adjustment, optical focusing elements (12) in the two telescope tubes (2, 3) can be displaced relative to one another, is distinguished by the fact that, as a result of rotation of a focus drive knob (5), both focusing elements (12) are displaced simultaneously by equal distances via a focus drive, the displacement of at least one of the focusing elements (12) can be locked (13, 14), and, as a result of rotation of the focus drive knob (5), while overcoming a frictional force in the focus drive to the locked focusing element (12), only the unlocked focusing element (12) is displaced.

Abstract: A play-free rotary mounting for a drive roll held on stop surfaces in the axial direction on a cylindrical body, wherein V-shaped annular grooves with an opening angle V are provided at least in one of the end faces of the drive roll and the stop surface located opposite them on the body, V-shaped bearing shells with at approximately identical opening angles and approximately identical leg length are inserted into the annular grooves, the vertex diameters of the annular grooves differ from the vertex diameters of the bearing shells. Balls with a diameter matched to the opening width of the bearing shells are inserted into the bearing shells. At least one of the stop surfaces can be adjusted in the axial direction in order to clamp the drive roll in. Instead of different vertex diameters, different opening angles can also be provided for the annular grooves and opening angles for the bearing shells.

Abstract: A slide projector with controls for the slide changing system and for the stop associated with the slide changing system where there are separately moving insertion and storage feeder arms for the slide changer, and at least two routes for inserting and removing the slides. Preferred motor driven cams (B",R",S",T") act as controls for the stop (8,11) and for slide changing and are operationally timed so that the closing process for the stop is initiated simultaneously or nearly simultaneously with the beginning of the removal of the projected slide (19a) from the slide stage plane and with the insertion of a new slide (19c). The process of stop opening begins immediately and without any pause after the complete closure of the stop which coincides with the terminated insertion of the new slide.