Abstract: In the line-by-line recording of films (15') for producing offset printing forms or in the line-by-line exposure of offset printing plates from recording data, i.e. density values of a line, the setting values for the individual zone screws are directly calculated from the density values and are stored or, respectively, directly forwarded to the printing machine (80). Before the forwarding of the setting values to the printing machine (80), density values are advantageously converted into the setting values with masks that, with reference to printing areas, printing surface in the pages (50) and with reference to the register system of the printing machine (80) as well as with reference to the characteristic data of a page (50), contain the allocation of the setting values of the zone screws calculated from the density values of the page (50).

Abstract: A method for operating a circuit arrangement to improve the bounce behavior of an electromagnetically driven engraving system by producing a correction signal from a stored original drive signal and supplying the correction signal to the engraving system chronologically preceding application of the original drive signal.

Abstract: A method for graving printing forms using rastered masters by means of a scanning system which can be adjusted in focus. The signal supplied by the scanner after processing in an electronic computer controls a graving system so as to scan rastered originals. The scanning system is placed out of focus and the loss of image information caused by placing it out-of-focus is compensated by means of an electronic out-of-focus mask.

Abstract: A method for measuring volume of surface depressions wherein the depression to be measured is or filled with a material which emits wavelength-shifted scatter light under irradiation. The material is illuminated with a light source whose wavelength lies in the absorption region of the material and the wavelength-shifted intensity of the scatter light of the material excited by the light source is measured with a photodetector, whereby the measured intensity is a measure of the volume of the surface depression.

Abstract: Process and apparatus for the white balancing of the opto-electrical converters of the scanning elements in reproducers for the point-by-point and line-by-line scanning of black and white documents and color documents. The light from the illuminant of the documents being scanned is converted in the opto-electrical converters into video signal levels or color signal levels, and the sensitivity or amplification of the opto-electric converters is so set that the video signal levels or color signal levels correspond to preset reference signal levels. The inconvenient process of scanning the illuminant of the document to be scanned, in order to obtain the light required for white balance, is replaced by a process by which the light from the scanning light source may be dimmed by means of a regulable iris diaphragm, thus corresponding to the scanning light from the illuminant of the document to be scanned.

Abstract: A method for electronic page montage for reproduction technology with recording of the pages on a recording medium by means of a recorder which comprises a multi-track recording element whose resolution is finer than the resolution of the image information, whereby, before the recording, the entire end page is divided into sub-areas within which the image information are to be recorded with the recorder in accord with a layout.

Abstract: An opto-electronic arrangement for line-by-line scanning of color originals in reproduction technology by means of photodiodes as the opto-electronic transducers characterized by a light source with a condenser system whose light is projected at a fiber-optical shape converter, whose output cross section forms a linear optical pattern which is focussed further by a cylindrical lens into a band shape onto the original. In one embodiment, a filter wheel is provided between the light source and shape converter and in another embodiment the photodiodes are provided with dichroitic filters for selecting the color of the light received from the original into desired colored patterns. In another modification, the first cylindrical lens focusses the light onto a diffusing element and then a second cylindrical lens is present for focussing the light from the diffusing element directly onto the original.

Abstract: Diaphragm arrangement for point-by-point electro-optical scanning of originals, whereby the scan point is composed of a central main field and of a surrounding field surrounding the main field. A diaphragm for scanning the main field and a second diaphragm for scanning the surrounding field are provided, whereby the sizes of the diaphragm apertures of the two diaphragms are continuously adjustable independently of one another, whereby the diaphragm apertures of the first diaphragm define the size of the main field and, thus, the scanning fineness and the inside diameter of the surrounding field, and the diaphragm aperture of the second diaphragm defines the size of the surrounding field, and whereby the size relationship between main field and surrounding field is continuously adjustable on the basis of the independent and continuous adjustment of the two diaphragm apertures.

Abstract: A laser diode imagesetter having multiple resolution operating modes, includes means for stabilizing the optical output power from the semiconductor laser diode during the scan trace interval across a photosensitive material so as to maintain a high extinction ratio for the laser diode even when its driving current is changed to a different level in order to operate the imagesetter at a different resolution mode.

Abstract: Image setting apparatus is disclosed for producing two-dimensional image on photosensitive material. The apparatus includes a device for transporting the photosensitive material past an imaging line to provide a first dimension of the two-dimensional image, a controllable source of electromagnetic radiation (EMR) for producing a modulated EMR beam, a scanning device for converting the EMR beam into a scanning beam, and a scan lens in the path of the scanning beam to focus the beam spot on the photosensitive surface. The beam spot thus moves repeatedly along the imaging line to provide the other dimension of the two-dimensional image. According to the invention, the EMR source is controlled to switch the EMR beam on and off at a frequency which is adjusted to compensate for variations in the scanning speed of the beam spot along the imaging line.

Abstract: Image setting apparatus is disclosed for producing two-dimensional images on photosensitive material. The apparatus includes a device for transporting the photosensitive material past an imaging line to provide a first dimension of the two-dimensional image; a light source for producing a modulated beam of light; a scanning device for converting the light beam into a scanning beam; and a scan lens in the path of the scanning beam such that a focused beam spot moves linearly and repeatedly across the photosensitive material along the imaging line to provide the other dimension of the two-dimensional image. According to the invention, the device for transporting the photosensitive material past the imaging line includes a driving roller in contact with the photosensitive material, a stepper motor mechanically coupled to rotate the driving roller and a controllable circuit, connected to the coil of the stepper motor, for incrementing the motor in microsteps upon command.

Abstract: A light transmission device for transmitting light from a stationary light source to a movable recording element of an electronic reproduction device composed of at least one fiber optical light waveguide and one guide element for the fiber optical waveguide. Due to the motion of a fiber optical waveguide, inhomogeneous light distributions arise at its exit face, this leading to disturbing streaked exposures of the recording medium. In the present invention to avoid such streak-like exposures, it is proposed that the guide element be a metal band which is mounted in a U-shape with the fiber optical waveguide being connected to one side of the metal band. Thus, as the recording element shifts, the curvature of the fiber optical waveguide remains constant to prevent shifting of the light distribution exiting the fiber optical waveguide.

Abstract: An opto-electronic scanning head for drum and flat bed scanning apparatus for point-by-point and line-by-line scanning of opaque and transparent originals which are illuminated point-by-point. The housing of the scanning head 7 has a front panel 9 which is displaceable along the optical axis 12 of the scanning objective lens 11 and has a housing part which is stationary with respect to the optical axis 12. The scanning objective 11 is mounted in the front panel 9, but the diaphragm 13 and the opto-electronic transducer 14 are mounted in the housing portion 8. The scanning objective 11 can be displaced over a broad range with a sensitive adjustment mechanism for the front panel 9 so that the focus range can always be placed into the image plane of the originals and thus optimum image sharpness can be achieved for originals having all different thicknesses.

Abstract: A method and circuit for driving a stepping motor which is driven by a motor clock output having a time variable frequency. So as to generate the time varying frequency, the constant frequency of a basic clock output is divided by constant first factor and is multiplied by a time variable second factor which is in the range between zero and the first factor. A transfer clock sequence is derived from the basic clock output by a division factor. The second factor is changed by a prescribed increment with the frequency of the transfer clock output at the respective clock times and this prescribed increment determines the frequency change of the motor clock output per clock interval. In this manner, the unavoidable frequency discontinuities can be maintained small and constant over the full frequency range of the motor clock output even by when the frequency of the basic clock output is not high whereby a reliable run-up and a reliable braking of the stepping motor are assured without stepping errors.

Abstract: An apparatus for scanning a transparency image original wherein scattered light emerging from the original is guided through lens or diffraction gratings onto a diffusion screen attached to a light mixer. In the light mixer, the light is mixed by multiple reflection and, at a light exit of the mixer, is guided to a cross-sectional transducer formed of a plurality of optical fibers. These fibers conduct the light onto a photoelectric transducer. The apparatus works with high efficiency and reduces an image falsifying influence of the Callier effect to such a degree that it no longer has a disturbing appearance in reproduction.

Abstract: A gas bearing is formed of a bearing member of sintered material. Sintered grains of a layer forming a desired bearing surface are deformed into the shape of a honeycomb in non-cutting fashion and are subsequently finely worked in cutting fashion, so that super-fine pores formed at corners of the honeycomb arise and which form nozzles.

Abstract: Pressure-tight vacuum chamber of an electron beam engraving machine for the acceptance of printing cylinders to be engraved, comprising a lower part similar to a machine bed, comprising a pressure-tight vacuum hood put in place on said lower part which is fashioned as a barrel-like arch and which is put in place on a sealing lip surrounding said lower part at its upper edge, comprising a loading opening for the printing cylinders situated in the upper central region of said hood and extending in longitudinal direction of said hood, comprising a cover lowerable into the loading opening and sealing with the loading opening, and comprising lifting and coveying devices situated at the face ends and at the loading opening with which the cover can be lifted out of its closed position and can be moved at the outer circumference of the hood in circumferential direction while releasing the opening in open position and can be moved back from the open position over the opening and be lowered into the closed position.

Abstract: In a picture-element-by-picture-element and picture-line-by-picture-line recording of printing forms, at least two picture signal sequences are acquired, and the picture signal sequences are influenced by mask signals. A recording signal sequence for the control of a recording element for the printing form is generated with the assistance of the influenced picture signal sequences. A signal sequence is acquired from every picture signal sequence, this signal sequence containing the picture signal values of the corresponding picture sequence to be recorded for picture elements lying within a sub-area of the printing form to be recorded and in which the picture signal values of the corresponding picture signal sequence which are not to be recorded for picture elements lying outside of the sub-area are respectively replaced by a mask signal value. The signal sequences are combined to form a resulting signal sequence.

Abstract: A holding device using a vacuum clamp arrangement has a suction box closed by a suction plate having a holding surface provided with a plurality of suction bores extending from the holding surface into the suction box. Each of the suction bores has an enlarged expanded bore portion inwardly spaced from the holding surface to form a valve chamber which valve chamber is closed by an inner section of the suction bore between the chamber and the suction box and each of the valve chambers loosely receives the shaped valve reed which will close the inner section of the suction bore for each of the suction bore arrangements which is not covered by the sheet placed on the holding surface. This simple structure keeps vacuum losses low and, therefore, enables utilizing a relatively small vacuum pump for the device.

Abstract: A method and apparatus for minimizing errors in digital processing of electrical signals whereby a digital input signal is divided into a digital useful signal having a lower resolution than the input signal and into a digital error signal having lower resolution than the input signal. A deviation of the useful signal is reproduced from the input signal and a check is performed to see whether the sum error of a plurality of successive useful signal values crosses a prescribed upper or lower threshold. When a threshold is crossed, an error value of the useful signal which comes closest to this threshold is identified and the useful signal and the error signal of this signal value are corrected such that the sum error no longer crosses the threshold.