Man Roland Druckmaschinen Ag

Grapho Metronic Mess- Und Regeltechnik Gmbh

Franz Lampersberger

Karsten Wendt

Michael Schönert

Peter Rakitsch

Hans Joachim Six

Rainer Tutsch

Bernd Tieleb&ouml;rger

J&ouml;rg Sierks

Andreas Walser

An apparatus and method for detecting a relatively narrow predetermined pattern, such as a trigger mark, on a moving printed product uses a plurality of sensor elements arranged linearly in an array and a switching apparatus for selecting a properly located subset of the sensor elements for detecting the predetermined pattern. During the operation of the apparatus, only those signals from sensors in the selected subset are checked continuously for the occurrence of a signal pattern corresponding to the predetermined pattern. Each time the predetermined signal pattern is found in the output signal from a sensor within the selected subset, a detection signal is generated. The lateral shifting of the predetermined pattern over time may be monitored by the selected sensors, and the selection of the subset of sensors for the continuous evaluation may be changed in response to the lateral shifting.

Apparatus and method for detecting a predetermined pattern on a moving printed product

A measurement device is described for the quality control of printed products, having a pair of optical channels that differ in their properties and operate simultaneously. Each optical channel comprises an illumination channel for illuminating a measurement location and a reflection channel that picks up the light reflected from the measurement location. The reflected light is directed to an evaluation unit, which is connected to the reflection channel, that analyzes the reflected radiation spectrally. Polarization filters arranged in one of the pairs of channels provides the difference in the optical properties between the two pairs of channels. The measuring device provides an increased number of obtainable measured values for further processing in a way that requires only a modest increase in the metrological outlay compared to other measuring devices of this type.

Measuring device for the quality control of printed products

A measuring system for registering reflectances on printed products, the measuring system having at least one illumination channel for producing a scanning spot at a point on a measurement field on the printed material. The system includes scanning channels for registering the reflectances of the spot from the printed material. The measuring system moves relative to the printed material. Measuring devices supplying ink density and spectral, preferably colorimetric, measured values are combined with one another without additional outlay in terms of construction. The combination of the measuring principles (density and color) are optimally adapted to the task of a measuring strips on the printed material scanned in the longitudinal direction. The measuring system has a densitometer that produces a scanning spot on the printed material, and a spectrophotometer that produces a further scanning spot on the printed material. The densitometer and the spectrophotometer are arranged one behind the other in the measuring head. The scanning spot of the densitometer and the scanning spot of the spectrophotometer are spaced apart from each other by a distance determined by the speed of the measuring system in the scanning direction and by the computational speed of the evaluation electronics, which are connected downstream of the densitometer and the spectrophotometer. The measured values from the densitometer may trigger the measurements and/or evaluations of the measured values obtained by the spectrophotometer.

Measuring system for registering reflectances on printed products

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Aschheim, Germany

Franz Lampersberger