Abstract: A video rear-screen projection apparatus includes a housing accommodating a fixedly arranged cathode-ray tube unit which is provided with a projection lens and which is secured to a frame. The apparatus also includes a first mirror pivotally connected to the housing so that the mirror can be located entirely inside the housing or can be extended with its reflecting surface facing the projection lens. The apparatus further includes a transparent screen which extends in the direction of width of the housing and is pivotally associated with a pivot on the frame, and also includes a second mirror pivotally associated with the housing. The screen and the two mirrors are arranged such that they can be extended so that the light rays from the cathode-ray tube strike the transparent screen or can be folded so that they are located inside the housing.

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 shaving unit for a dry-shaving apparatus comprises an external first cutting member with an annular wall portion formed with hair-entry apertures, and a second internal cutting member which is cooperable with the first cutting member and which comprises a ring of cutters which second cutting member can be driven relative to the first cutting member with an oscillatory rotational movement. The first and second cutting members are interconnected by at least two resilient elements, each of which extends substantially radially of the rotational axis of the second cutting member and has an end connected to the first cutting member and an end connected to the second cutting member. The elastic properties of the resilient elements are such as to permit the oscillatory rotational movement of the second cutting member, but the resilient elements are rigid in directions extending substantially parallel to and radially of the rotational axis of the second cutting member.

Abstract: The device comprises a transducer (3) with photoelectric elements (31) and a coupling member (5) which comprises an entrance face (9) which is to be aimed at the document and an exit face (11) which is optically coupled to the transducer. The coupling member (5) comprises a number of light conductors (7) having first ends (13) which are arranged in at least one straight line in the entrance face (9) and second ends (21) which are situated in arbitrary positions in the exit face (11). The relation between the positions of the first ends (13) in the entrance face (9) and the positions of the second ends (21) in the exit face (11) is stored in a memory (29). The photosensitive surface of the transducer (3) may have an arbitrary length/width ratio and the light conductors (7) may extend rather arbitrarily through the coupling member (5) so that the cost of the device may be comparatively low.

Abstract: A system for recording/reading information, comprising interchangeable disc units and a drive unit. Each disc unit comprises a disc pack with at least one information disc which is contained in an enclosure comprising two covers which can move relative to each other and which are interconnected by connecting means. The drive unit comprises means for supporting and driving the information-disc pack and means for recording/reading the information on the information discs, means for releasing the connection between the covers, and means for moving the covers relative to each other.

Abstract: An optical communication element comprises an optical fiber bonded in a state of axial compression to a metal tape. The tape may be folded up into a tube and sealed by soldering. Such elements are strong and not sensitive to stress corrosion. Such an optical communication element may be produced by passing a metal tape and an optical fiber in contact around a drum with the optical fiber on the outside. An adhesive, which solidifies or cures during the passage around the drum is applied to the metal tape.

Abstract: An optical communication element comprises an optical fiber bonded in a state of axial compression to a metal tape. The tape may be folded up into a tube and sealed by soldering. Such elements are strong and not sensitive to stress corrosion.Such an optical communication element may be produced by passing a metal tape and an optical fiber in contact around a drum with the optical fiber on the outside. An adhesive, which solidifies or cures during the passage around the drum is applied to the metal tape.

Abstract: A connector for connecting optical fibers comprises three portions:a. centering means for centering the fiber with respect to a housing in which the fiber has been inserted,b. a profiled edge on each housing for centering housings with respect to each other, andc. fixing means for connecting two housings to each other.The edges of the housings are resilient with respect to the rest of the housing so that reference faces of the connector can be pressed together by springing back the edges.

Abstract: Microlenses which are easy to handle are produced by providing rotation-symmetrical recesses in a glass plate, depositing vitreous layers by means of a vapor deposition process onto the plate, until the recesses are fully filled up, whereafter the thickness of the coated glass plate is reduced to the original value or to a smaller value. Two lenses produced in this manner are then combined to one lens by placing the embedded lenses on top of one another by means of their flat sides.

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 television camera in which a color splitting prism and a number of pick-up tubes are positioned, with respect to each other in a holder which comprises an annular seat for optical alignment of each pick-up tube, the relevant pick-up tube being pressed onto said seat, by way of an adapter ring connected thereto transversely of the tube axis, by means of a resilient pressure member which acts in the direction of the tube axis. The diameter of the parts of the seat and the adapter ring decreases in the pressing direction. The pick-up tubes fit in the holder in a locating manner and, after being pressed, do not exhibit play with respect to each other, so that variations of the position with respect to each other in reaction to shocks, and inherent picture registration errors, are avoided.

Abstract: A method of breaking optical fibers, a fiber being scored over the entire circumference in a plane perpendicular to the fiber axis. By subsequently applying a predetermined axial tensile force to the fiber, fracture is initiated over the entire circumference of the fiber. As a result of this, fibers with a comparatively large diameter can be broken in such a way that a mirror zone is obtained across the entire fracture area. Circumferential scoring also ensures the required accuracy in respect of the perpendicular orientation of the fracture plane relative to the fiber axis.

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.