Abstract: Copy machine has a paper storage magazine into which at least two paper sheet cassettes and decollation devices can be introduced which are associated with each paper sheet cassette and can be driven through individual driving motors so that a separate sheet can be fed arbitrarily from one of the driven cassettes into the office machine. The readjustment to a mode of operation with additional paper sheet cassettes can be carried out in a single manner by unskilled operators if the paper sheet cassettes (2,3,4) constitute with their associated decollation drives (5,6,7) a constructional unit, whose electrical motor terminals can be connected through connection plugs to control sleeves of the office machine (1).

Abstract: A height-adjustable table for supporting a patient during medical examination or treatment in which a patient support table top mounted on a carrier 2 is connected to a base 3 by a parallelism maintaining linkage comprising a diamond or rhombus shaped linked assembly of four mutually pivoted equal struts 6, 7, 8, 9, pivotally attached top and bottom to the carrier 2 and to the base 3, and intermediately to the centers of first and second struts 17, 18 which are attached at their ends for free rectilinear displacement, to slides 20, 22, 24, 26, mounted on the carrier 2 and the base 3. Inextensible diagonal links 30, 32 connect diagonally opposed slides 24, 22 and 20, 26, to form an assembly of good horizontal and vertical stiffness even at the maximum height adjustment which is effected by e.g. a screw jack 5.

Abstract: A method of scanning objects by means of ultrasonic echography, including the transmission of ultrasonic waves to the object to be scanned by means of a transducer array (101) and the reception and processing of the echographic signals corresponding to the echoes returned. Digitized A-lines are divided into n elements of p points and, after various operations, the reconstruction of the elements of the echographic lines by selection of principal vectors which imply factors which imply a reconstruction of the matrix sum of the series of unity matrix products relative to said selected principal vectors.

Abstract: A charge coupled device (CCD) sensitive to infrared radiation composed of a succession of three layers of Group III-V semiconductor material. The layers are a window layer, a sensitive layer and a storage layer. The layers are fixed to a supporting plate serving as input for the radiation and as a rear surface of the device. The front surface of the device supports a plurality of control electrodes and at least one output electrode.The window layer and the storage layer of the CCD are made of a binary compound AB. The sensitive layer is made of an n-ary compound (A,X,Y . . . ).sub.III (B,M,N . . . ).sub.V having a larger forbidden energy band and a smaller absorption limit wavelength than the window and storage layers.The three layers of the device are formed by epitaxial growth on a substrate. The substrate is a layer of the binary compound AB coated with an epitaxial layer of the n-ary compound. The epitaxial substrate layer is a chemical blocking layer.

Abstract: A planar reflecting grating is described which is suitable for use in an optical multiplexer or demultiplexer. This grating comprises a periodic structure of elongated areas which are formed at constant distances from each other in a thin light-conducting layer deposited on a substrate. In their longitudinal directions, the areas have periodic ridges, corresponding ridges extending parallel to each other.

Abstract: A device for binarizing an image consisting of grey values by means of a dynamically adjusted black/white discrimination threshold comprises:a. a generator (74) for determining a discrimination threshold each time for a first local sub-set of pixels;b. an edge detector (90) for determining a local edge between darker and lighter pixels from a second local sub-set of pixels, associated with a first local sub-set of pixels, in order to form an accept signal, and otherwise a reject signal; andc. a discriminator (64) for presenting, on the basis of a grey value and the relevant discrimination threshold, alternatively a black or a white signal.

Abstract: In a data communication system comprising a plurality of data stations which are interconnected by a common communication medium, simultaneously occurring prospective users of the communication medium undergo an arbitration to determine which one will gain access to it at any time. The system according to the invention provides the arbitration without negatively affecting the capacity of the communication medium. In the system, arbitration takes place during the data communication to decide who will be the next user, arbitration and communication being effected in frequency bands which differ from each other.

Abstract: A personnel protection circuit for electrical supply systems comprises a normally closed switch connected between a source of electric power and a load. Two parallel conductors are connected between the switch and the load, and include a control circuit having a current unbalance detector for detecting current unbalance between the two conductors. Upon detection of such current unbalance, the normally closed switch is opened thereby disconnecting the electrical supply. Such control circuit devices may be included in both lines of the electrical supply system between the source and the load, or alternatively, further control circuit devices may be provided at both the source end and the load end of the parallel conductors.