Abstract: A manipulator having an object holder which can be moved in three directions of translation and three directions of rotation. The object holder is connected by coupling members to driving members secured to a frame. A modular construction is obtained by making the coupling members for the directions of translation and the directions of rotation identical to each other, respectively. The driving members for the directions of translation and the directions of rotation, respectively, are also identical. The modular construction results in a very accurate construction with a minimum number of different components.

Abstract: A positioning device having a plate-shaped carrier (5) which is displaceable in a horizontal plane and which is journalled on a table (1) and on which is exerted a pressure and tensile force, respectively, by means of at least two translation drives (11, 13). The translation drives (11, 13) are coupled to the carrier (5) by means of horizontally operating static thrust and tensile bearings, respectively (33 to 41, 49), which transfer via a viscous medium in a contactless manner pressure and tensile forces respectively, between the carrier (5) and the translation drives (11, 13). The contactless bearings (33 to 41, 49) are pre-stressed with a force which is larger than the maximum occurring tensile force between the drives (11, 13) and the carrier (5). Thus, a substantially frictionless coupling is obtained between the drives (11, 13) and the carrier (5). This coupling acts at the same time as a guide for the carrier (5).

Abstract: A method of and a device are provided for the high-precision manufacture of glass lenses where a roughly metered volume of softened glass is transferred in a product holder from a furnace to a position between two moulds, the moulds being subsequently moved towards one another and the excess glass being pressed from between the moulds. The moulds and the product holder are moved at such a mutual speed that both moulds simultaneously contact the article, and the movement of the moulds is terminated when they reach a given position with respect to one another.

Abstract: The invention relates to a method of and a device for providing an outer surface of an envelope which is concentric to a light-conductive core, around a monomode optical fiber. According to the invention, the eccentricity of the fiber and the envelope may be for example, 0.1 .mu.m for a core diameter of 3 .mu.m. This accuracy is acieved by splitting a light beam, emerging from the end of a fiber which is clamped in an envelope, into two subbeams by means of rotating optical means, each of the beams producing a circular image. By a suitable choice and adjustment of the optical means, the two light beams will form oppositely moving images when the fiber end is displaced with respect to the axis of rotation and observation. When the images are concentric, the fiber end is situated on the axis of rotation. Machining of the envelope by the use of a tool which rotates around the axis of rotation results in an envelope which is concentric to the light-conductive core of the fiber.

Abstract: A pressure energy accumulator having a mixture consisting of CF.sub.4 or C.sub.2 F.sub.6 and N.sub.2, H.sub.2, or He, or a combination thereof, as the gaseous working medium.