Abstract: In a method and apparatus for producing half-tone printing forms with screens having arbitrary screen angles and screen width, screen dots are exposed on a recording medium by means of a recording element whose exposure beam is switched on and off by a control signal. The recording medium is sub-divided into a plurality of areal elements which are exposed or not exposed by the exposure beam as a function of the control signal. All areal elements exposed in a screen mesh of the rotated screen to be recorded form a respective screen dot. At least two matrices in the form of matrix memories are provided, the individual matrix elements thereof having screen threshold values allocated to them. The screen threshold values forming a screen hill represent the periodic basic structure of a screen mesh and are different for at least one tonal range in the individual matrices.

Abstract: A method and apparatus for acoustic supervision of adjustment of a light bundle with respect to its intensity distribution in a reference plane which is at right angles to the optical axis of the light bundle. The reference plane is subdivided into surface elements. The intensity values corresponding to a rated intensity distribution are prescribed and stored for the individual surface elements of the reference plane. The intensity values for the individual surface elements respectively existing in the adjustment are successively measured in rapid cyclical succession. The intensity deviation from the prescribed intensity value is identified and stored for each surface element. The stored intensity values are read-out in slow cyclical succession and are made audible as measuring tones for the supervision of the adjustment.

Abstract: A method and apparatus for acoustic supervision of adjustment of a light bundle composed of component beams with respect to its intensity distribution in an expanse of a reference plane situated in a beam path at right angles to an optical axis of the light bundle. Intensity values I of the component beams lying at a margin of the light wave are measured and the differential intensity values .DELTA.I are identified according to amount and operational sign. An oscillation is generated whose parameters are modified dependent on the amounts and operational signs of the respective differential intensity values. The modified oscillation is made audible as a distinguishable measuring tone for amounts and operational signs of the differential intensity values .DELTA.I.

Abstract: Apparatus for checking or, respectively, correcting a color picture to be printed on a monitor, whereby reference colors stored for color checking by means of a coordinate acquisition means can be made visible in a reference color field at abitrary locations of the color picture.

Abstract: A method for producing printing cylinders for seamless or endless patterns with printing form engraving machines having a scan cylinder and an engraving cylinder. A pattern original on the scan cylinder is opto-electronically scanned picture-element-wise along scan lines lying next to one another which run in a circumferential direction of the scan cylinder, and where every scan line supplies the information for an engraving line of a pattern repeat to be transmitted onto the printing cylinder. The scan original is longer than the pattern repeat (original extension). In a mixing region, picture elements of the original extension and of the beginning of the original stored for every scan line are combined in accordance with a prescribed mixing function to form picture elements having a new density information.

Abstract: In electronic reproduction technology, a method and apparatus for production of color separations from color originals for single color printing. The color original is opto-electronically scanned point-by-point and line-by-line for generating measured color values. Chrominance values are obtained from the measured color values by an adjustable coordinate transformation, and a hue signal is acquired from the chrominance values by quotient formation. A hue control signal is derived from the hue signal, said hue control signal having a maximum value for a selectable separation hue of a color of the scanned original and becoming zero for an adjustable, maximum deviation from the separation hue. During recording of the color separation of a separation hue, the hue control signal is directly employed for controlling the recording element which records the color separation point-by-point and line-by-line.

Abstract: Offset printing plates are usually supplied from the manufacturer as a plate stack with intermediate paper layers. For further processing, the plate stack is placed in a magazine cassette. A suction plate lifts a top plate off from the stack and, after removal of the intermediate paper layer by means of blowing air, conducts it for further processing. Also by means of blowing air, the respective upper plates of the remaining stack are isolated, so that they no longer firmly adhere to the stack. Undesired dislocations of the plates thus arising are mechanically corrected.

Abstract: Record quality of a bit map of a newspaper page, for example, is checked directly on a display screen without previously manufacturing a material image carrier, such as a film. For this purpose, it is read out in multi-line fashion, preferably in 4 - line fashion. Squares consisting of m (preferably likewise 4) successive points of n (preferably 4) superimposed lines are grouped into one "superpixel" each, and its gray value, for example, is determined as an average of the black-white values of the individual pixels forming the square. The superpixel is displayed with its gray value as a single point on the display screen instead of the m.times.n square.

Abstract: A mounting device for reproduction apparatus has receiving surfaces for an original copy and a recording medium. The surfaces are provided with suction holes charged by means of an underpressure. The suction holes of the receiving surfaces for the original copy and recording medium are connected to a common vacuum line, and the suction holes of at least one of the two surfaces are connected with the underpressure via a throttle.

Abstract: A method and circuit arrangement for selective correction of hues and colors in the production of color separations for polychromatic mixed printing. A hue signal identifying the hues of the scanned colors as well as a color saturation signal and a luminance signal are derived from the measured color value signals acquired when scanning the original. Hue signals, color saturation signals and luminance signals are limited such that they are respectively not equal to zero only for selectable regions. The region of the hue signal defines a hue to be selectively corrected, and all three regions of the signals define a color to be selectively corrected. At least one of the limited signals is combined with at least one of the unlimited signals to form the selective correction signals which are superimposed on the color signals to be corrected.

Abstract: Method and apparatus for determining the trimmed image of originals for reproduction with opto-electrical original scanning wherein a mask is produced before the actual original scanning and the mask includes clearance for receiving the original therein. The mask and original are adjusted with respect to the desired trimmed image and the angular position by placing it in a projection head of an apparatus for scale identification wherein the holder of the original can be removed from the projection head of the apparatus and hinged downwardly for performing these functions.

Abstract: A method and apparatus for isochromatic simulation of a multi-colored reproduction on a color monitor. Before simulation, colors are generated on the color monitor and are matched to corner colors of a printed color chart or the like by measuring or visual comparison. The color values required for the chromatically coinciding generation of the corner colors on the color monitor are measured and allocated to color separation values of the corner colors. The color values required for generating intermediate colors are calculated upon consideration of the printing process of the multi-colored reproduction and are allocated to the corresponding color separation values of the intermediate colors. During the simulation, the color separation values of the multi-colored reproduction are output, modified according to a gradation curve, and transformed into the color values for driving the color monitor in accordance with the previously identified allocations.

Abstract: A device for automatic loading of film material on a suction plate by transport roller pairs arranged at two oppositely disposed ends of the suction plate. One pair receives the film material and the other pair further transports the film material. At the two other lateral sides or ends of the suction plate, a roller is respectively provided extending over an entire side of the plate. A cloth can be wound on this roller such that the roller and cloth are so arranged that they respectively form a blind covering the suction plate up to and overlapping lateral edges of the film material.

Abstract: In electronic reproduction technology, a method and an apparatus for the production of hue and color separations for single color printing. A color original is optoelectronically scanned to obtain measured color value signals. A recognition region for a selected separation hue is defined in a recognition circuit. A hue recognition signal, which is a measure for the hue deviations of the hues scanned in the color original from the selected separation hue, is generated from the measured color value signals. Corrected color signals are derived from the measured color value signals and at least one corrected color signal is selected for further processing. A recording signal is acquired in a mixer stage by mixing the selected color signal and the hue recognition signal. The recording signal controls a recording element for recording of the hue separation.

Abstract: A method and apparatus for element-by-element and image-line-by-image-line recording of print characters on a full page by means of an exposing beam deflectable over the full page, and which is switched on and off by a control signal. The characters are stored in a character memory in the form of contour-coded character data. The contour-coded character data are read out of the character memory in the sequence required for exposure and are converted into control signals suitable for the image-line-by-image-line recording of the characters.

Abstract: Apparatus and method for producing qualitatively high-grade color images of originals such as copy masters for multi-color or process printing by exposing chromatic material wherein the originals are scanned point-by-point and line-by-line and the color signals thus obtained are converted into color density values for the chromatic material by means of a correction of color and of gradation. The drive values for a color exposure unit which exposes the chromatic material point-wise and line-wise are generated from the color density values using a linearization process. As a result of signal inversion color positive originals can be recorded as color negatives and vice versa. The exposure process can be matched to every chromatic material independently of the nature of the original to be reproduced and the state of the developing process by means of changing the color density values according to an arbitrarily selectable correction function and by means of signal inversion.

Abstract: In electronic reproduction technology, a recognition circuit for hues and colors in colored surfaces is provided. Before the actual hue recognition, the hue to be recognized is selected and its prescribed or measured color values of the RGB color space are transformed by a first color transformation into chrominance values of the chrominance/luminance color space, whereby the transformation coefficients are defined such that the transformed color locus of the hue to be recognized lies on a rotated X'Y' color coordinate system in the chrominance plane. During the actual hue recognition, the colored surface is opto-electronically scanned and the measured color values acquired are transformed into chrominance values by a second color transformation with the transformation coefficients defined in the first color transformation.

Abstract: A single piece electrode comb or device includes two circuit boards having conductor paths and two separate rows of needle-like recording electrodes which are electrically connected to separate paths of the respective circuit board encapsulated in a single plastic resin body with the electrode rows extending to a recording edge formed in a rib along one edge of the body. To form the electrode comb, a device having two substantially similar rectangular cross-sectional shaped halves is assembled in one position to form a winding core on which a wire is wound with a plurality of turns, clamped and joined to the respective circuit boards which are mounted on faces of the two halves, subsequently the wires are separated along a parting plane and the two halves are disassembled with one being rotated 180.degree.

Abstract: Scanning apparatus and method for scanning rastered reproduction of differently rastered masters in reproduction technology using electronic means for selecting a shaped diaphragm which is variable in its geometry during scanning and wherein a center portion of the scanned picture can be added to different edge geometry scanning configurations so as to eliminate Moire effect.

Abstract: A single piece electrode comb or device includes two circuit boards having conductor paths and two separate rows of needle-like recording electrodes which are electrically connected to separate paths of the respective circuit board encapsulated in a single plastic resin body with the electrode rows extending to a recording edge formed in a rib along one edge of the body. To form the electrode comb, a device having two substantially similar rectangular cross-sectional shaped halves is assembled in one position to form a winding core on which a wire is wound with a plurality of turns, clamped and joined to the respective circuit boards which are mounted on faces of the two halves, subsequently the wires are separated along a parting plane and the two halves are disassembled with one being rotated 180.degree.