EP0836942A1 - Measuring block and method for quality data acquisition in multicolour sheet-fed printing machine - Google Patents

Abstract

The measurement field group consists of optically scanned measurement fields (A1-D3) printed onto the printed products. Each measurement field has at least one colour measurement area (F) for determining colour density, surface coverage or a colour value for each measurement field. Each measurement field has at least one lateral colour strip (S) for the simultaneous determination of registration, displacement and doubling values, which is printed during the same printing as the colour measurement area of the measurement field. The lateral strip is small compared to the colour measurement area and is close to it.

Description

The invention relates to a measuring field block and a method for detecting Quality data in multi-color edition printing according to the generic terms of the independent Expectations.

To record quality data in multi-color print runs, especially the Numerous solutions are known for commercial and newspaper printing. The quality data acquisition, for example of paint, paint layer thickness, register, sliding, Duplication values, area coverings and the like are used for monitoring and Control of coloring in multi-color printing.

EP 0 196 431 B1 describes a method for achieving a uniform printing result on a multi-color offset printing press that works in an autotype. Color layer thicknesses or solid color densities and screen dot sizes or Area coverage line measured on measuring fields, for each printing ink in each Inking zone of the printing machine. Because of the densitometric The ink guide actuators on the press are automatically measured set. Since several measuring fields are also printed in each color setting zone of the machine this method is suitable If several measuring fields are printed in the zone of the machine, this method is suitable for commercial offset printing, but not for newspaper offset printing, where the In contrast to commercial offset printing, measuring fields are also printed within the type area and cannot be cut away after printing. Accept newspaper publishers these measuring fields are therefore reluctant.

Another obstacle to the use of this known method in newspaper offset is To be seen in the high equipment and personnel expenditure, which for measuring the measuring fields must be operated. Should the web offset measurement be online, i.e. automatically at the running web, there is an optical measuring head with automatic for each web side Positioning necessary. Would measure instead with commercially available hand densitometers or handheld spectrophotometers should be taken into consideration the large number of measuring fields and the time required for manual measuring device positioning Personnel are available especially for the purpose of quality data acquisition. Furthermore with the solid and screen densities of the individual colors using this known method Characteristics measured, which have a direct connection to the printing process, however little about the color appearance of the finished multicolor printed product statement.

Statements about the color perception can be made by means of printing and colorimetric measurement can be obtained from combination measuring fields, as is particularly the case in DE 44 02 784 A1 and DE 44 02 828 A1 is known. By using the described there The measuring field block becomes the space required for the printed product to be checked printed measuring field or the measuring field block significantly reduced. However allowed this measuring field or the measuring field block known from it does not yet record Measured values for ink acceptance in multicolored overprinting, for registration and also not for the detection of processing problems such as pushing and duplicating.

Procedure for determining registration errors and measuring register marks suitable for measurement are known from DE 44 37 603 A1 and DE 40 14 706 A1. Such registration marks would have to be printed on the printed product to be checked in addition to the color marks and be measured with an appropriate measuring device. At least it has to two measuring devices are mastered and used.

With the progressive introduction of color management in the printing industry Another Problem. The idea of color management is known to be that Color templates in digital prepress independent of output devices and materials be determined. The colors of a picture template are in one by the commission Internationale de l 'Eclairage (CIE) standardized colorimetric coordinate system, such as CIEXYZ, CIELAB or CIELUV. If the output is defined in this way multicolored images on paper over a calibrated in terms of color management System, it is ensured that the color appearance of the printed product to the Original is comparable, regardless of the output process used.

Computer color printers, digital color copiers, among others, are calibratable output systems and digital proofing devices in use. It is worth pursuing the concept of Color management also on conventional printing processes, such as newspaper offset printing, expand. The existing of printing form production and printing process Effect chain treated like any other calibratable output device.

With the availability of systems for the production of color profiles of the printing process an important prerequisite is fulfilled. Another problem is how the new ones Color management tools combined with those specific to the printing process Control and regulation mechanisms (densitometry and colorimetry) function sensibly can.

When creating color profiles, it is namely necessary to take special test patterns precisely print and measure defined conditions. This is expensive because it does Machine hours and material are consumed. It would be desirable to do the calibration the color profiles of the printing process are not preventive, but only to be carried out when it has become absolutely necessary. A tool that due to Edition printing can decide whether it is true, but does not yet exist.

The invention has set itself the task of quality data acquisition in multi-color production printing, preferably in offset printing and preferably not only for commercial offset but also for newspaper offset printing. Here, on the one hand the space required for the measuring elements required for determining quality data or Measuring fields are reduced compared to known solutions, and it should be the measuring technology Effort can be kept low.

This object is achieved by the formation of a measuring field block according to claim 1 and by means of of a method according to claim 17.

The invention is based on a measuring field block, which is formed by several measuring fields is used to obtain color values, color densities or surface coverings or a Combination of these are suitable. Suitable here means that the measuring fields are large in each case are enough to use the measurement techniques available to determine these values to be able to measure, i.e. the measuring fields must have color measuring areas of sufficient size exhibit.

According to the invention, the measuring field block has at least one for simultaneous determination a value for a register deviation, i.e. a register value, lines in primary colors that are used for a print. There are thus measuring elements in the measuring field block, namely the mentioned measuring fields and the lines, combined, which are the same Measurement field block a measurement and determination of a register deviation based on it and permitted by densitometric and / or colorimetric values. With a suitable one Measuring device is the measurement and determination based on such the print image determining values possible with a single measurement.

The lines preferably run between two of the measuring fields of the measuring field block through it. Very particularly preferably, there remains immediately on both sides along such a line, exact register provided an unprinted area. However, it can also be beneficial be the neighboring measuring fields, between which a line for determining the register to connect directly to such a line. In these two versions neighboring measuring fields of the measuring field block are thus separated from one another by a line separated.

It may also be advantageous if one, some or all of the lines are used to determine the Pass through one or more measuring fields of the measuring field block, in particular if the measuring field block has too few measuring fields to be used for the Determination of all register values, all lines between the measuring fields or immediately to the side of the outer measuring fields of the block.

There is preferably at least one line for each of the primary colors of the respective print at least one direction in which a register deviation is to be determined, intended. There is preferably at least one line for each of the primary colors Determination of the register deviations in a first direction and at least one each another line to determine a register deviation in another direction intended. At least one line in the circumferential direction is preferred for each primary color and present in the longitudinal direction of a printing cylinder. Is particularly preferred for the as Reference color serving base color another line for the at least one, preferably however, there are two directions in which a register deviation for at least one of the other primary colors to be determined. The distance between the two in the same The directional lines of the reference color are measured and used for coordination or calibration of the distances measured by the same measuring device into the same Direction lines for the other primary colors.

According to the invention, in addition to their color measurement areas, the measurement fields can each have at least one a color strip to determine the register and / or push and / or duplication have at least one color strip per measuring field in the same print is printed together with the color measuring surface of its measuring field, in relation to the Dimensions of the color measuring surface of his measuring field is narrow and in a predetermined, also in relation to the dimensions of the color measuring surface, close to the side Color measurement area runs.

With a single touch, each of the measuring fields according to the invention can be next to a color value, the color density and / or the area coverage in the color measurement area, by measuring the zone or area between the color measurement area and its lateral one Color strips a shift and / or duplication value determined for the printing unit in question will.

It is particularly advantageous if the color strip and the color measuring surface of the individual Measuring field are separated from each other by a color-free zone, since the measurement in this Trap is most optimal.

Since the at slide and duplication-free pressure at least not in the pressure in question printed area between the color measuring areas and their lateral color stripes because of the borders on both sides, through the color measuring surface on the one hand and the color stripe on the other hand, the shift and / or duplication values can be determined.

By a predetermined boundary of the zone to be measured by an edge of a Color measurement area is formed, the combined measurement of color and sliding / duplicating space-saving possible on the same measuring field.

In a preferred development, the measuring fields each have at least two of these lateral ones Color strips for determining sliding and duplication in the circumferential and lateral directions on. The zones between the color measurement areas run very particularly preferably and their lateral color stripes in the circumferential and lateral directions; two like that on one Zones formed in individual measurement fields therefore run at right angles to one another.

To determine the register values, instead of or in addition to the lines between the measuring fields, the relative positions of the measuring fields, preferably the lateral ones Color strips of the individual measuring fields can be determined to each other. Because of the invention In this case, too, training of the individual measuring fields is not necessary additional registration marks can also be printed. Because the zones between the color measurement areas and their lateral color stripes when printing the measuring field in question can also be printed, the register values on the measuring fields according to the invention be determined.

If the measuring field block has the aforementioned lines and measuring fields with color measuring areas and Color strips slightly spaced laterally therefrom are used to determine the Register values preferably the lines and to determine the sliding and / or Duplicate values the color strips used. If the measuring fields the color strips mentioned have, but the aforementioned lines are not present, which is also one preferred embodiment corresponds, it is still possible, the register values and / or to determine shift values and / or duplication values by means of the colored strips.

The measuring fields are preferably at least single-color full-tone fields in the respective primary colors, generally cyan, magenta and yellow for four-color printing, or corresponding single-color grids, in which the basic colors in each case are printed with their nominal area coverage. If both solid densities and single-color full-tone fields and Individual color grids printed in the primary colors.

A solid tone field in black can also be used in each of the above combinations be provided. In addition or instead, there can be a halftone field in which the color Black is printed with their nominal area coverage.

In a still more preferred embodiment, in addition to any of the aforementioned Combination measuring fields can be provided, in each of which at least two basic colors with their nominal area coverage are printed on top of each other, so that meaningful values regarding the ink acceptance behavior are determined can.

Finally, in a preferred further embodiment, each of the aforementioned Measuring field combinations, an additional combination measuring field can also be printed, in which all primary colors with their nominal area coverage are printed on top of each other are.

The aforementioned measuring fields or a selection of them can also be shown individually in the picture also be printed, i.e. they do not all have to be combined in one according to the invention Measuring field block can be arranged.

In a preferred embodiment variant, provided that the register is exact, they are in shape a single compact measuring field block arranged and printed, so that the neighboring measuring fields with their color measuring areas or their lateral color strips blunt or collide on the lines or color measuring surfaces or the color strips keep a small distance from each other or from the lines. Furthermore are also Mixed forms of all design variants possible, in which several measuring fields to such Arranged measuring field blocks and possibly several such measuring field blocks, each with different measuring fields are provided; Individual fields can also be added be printed in the picture.

When using a single compact measuring field block, the use of a suitable measuring device, provided all the quality by means of a single touch of the printed product influencing values, namely the register values, sliding and Duplication values as well as color density, color acceptance and color balance values, color values, Area coverings and the like or a desired sub-combination determined will.

In a preferred method for recording quality data in multi-color production printing will include at least single color measuring fields in the primary colors Color measuring fields, preferably in cyan, magenta and yellow, and lines in the basic colors printed on a printed product, the individual color measuring fields at least one for Obtaining suitable color values or color density values or area coverage Have color measuring area. The measuring fields and lines are optically scanned and the remitted Light is evaluated, using register values by measuring the metric layers of the lines to each other can be obtained.

In one embodiment, at least one is used to form the measurement fields Color strips to determine if necessary also the register, but in any case the Sliding and / or duplicating, in the same pressure together with the color measuring surface of the Measuring field printed, which in relation to the dimensions of the color measuring surface of his Measuring field is narrow and in a predetermined, also in relation to the dimensions the color measurement surface runs a small lateral distance to the color measurement surface. Sliding and Duplicate values are determined by measuring zones thus formed between each Color measurement area and the color strip of the individual measuring fields.

Image areas of the printed product can advantageously serve as measuring fields.

The measurement fields are preferably recognized by image analysis.

Preferably, several of the measuring fields are in the form of a compact measuring field block printed side by side in such a way that their side-facing color stripes face each other butt with an exact register or a specified narrow distance from each other.

The image processing process preferably comprises a color separation, the generation of a Binary image and a feature-specific mathematical algorithm for determination the shift and duplication values, register values and color density values or area coverage.

A diagnosis can be made on the basis of the quality data obtained will.

Measures to improve the print quality are recommended from the diagnosis.

The measures preferably include compensation of the pressure characteristics, which is both material and printing unit and machine specific.

A correction of the press setting can be made from the diagnosis and the quality data obtained calculated and the printing press with these correction values can be controlled.

Diagnosis is particularly preferred in the form of a computer program following the given decision tree.

The diagnosis and the optional calculation of a correction of the Press setting preferably created with a neural network.

The diagnosis and the optional calculation of a correction of the press setting is preferably created with fuzzy logic.

A particularly preferred measuring device has a sensor, preferably a photoelectric Sensor, with spectral or at least 3-area and two-dimensional spatial Resolution on. A CCD color camera is preferably used, which is placed on a microscope is mounted.

If the measuring fields are arranged individually and in suitable measuring field blocks Subcombinations can also be printed on the image and distributed to those interested Still measure quality data using a single meter. The In this case, the measuring device can be moved over the continuous printed product arranged. From the prepress stage, the traversing control of the measuring device becomes the locations of the measuring fields or measuring field blocks to be probed.

Fig. 1

ein Messfeld,

Fig. 2

einen kompakten Messfeldblock mit nebeneinander angeordneten Messfeldern nach Fig. 1,

Fig. 2.1

die Verallgemeinerung des Messfeldblocks der Fig. 2,

Fig. 2.2

einen kompakten Messfeldblock für den 8-Farbendruck,

Fig. 2.3

zwei nebeneinander angeordnete Messfelder eines Messfeldblocks,

Fig. 3

einen Entscheidungsbaum zur Optimierung der Farbwiedergabe in einer einzelnen Auflage,

Fig. 4

einen Entscheidungsbaum zur Optimierung der Farbwiedergabe über mehrere Auflagen,

Fig. 5

zwei Messfeldblöcke mit integrierten Linien zur Bestimmung von Passerwerten,

Fig. 6

eine Erweiterung der Messfeldblöcke nach Fig. 5,

Fig. 7

eine Variante eines Messfeldblocks mit integrierten Linien,

Fig. 8

den Messfeldblock nach Fig. 2 mit integrierten Linien, jedoch ohne Farbstreifen,

Fig. 9

eine Variante des Messfeldblocks nach Fig. 8 und

Fig. 10

den Messfeldblock nach Fig. 2 mit integrierten Linien.

A preferred exemplary embodiment of a measuring field and a compact measuring field block as well as two methods for optimizing the color reproduction in multi-color print run are described below with reference to figures. Show it:

Fig. 1

a measuring field,

Fig. 2

1 shows a compact measuring field block with measuring fields arranged side by side according to FIG. 1,

Fig. 2.1

the generalization of the measuring field block of FIG. 2,

Fig. 2.2

a compact measuring field block for 8-color printing,

Fig. 2.3

two measuring fields of a measuring field block arranged side by side,

Fig. 3

a decision tree to optimize color rendering in a single edition,

Fig. 4

a decision tree to optimize the color rendering over several editions,

Fig. 5

two measuring field blocks with integrated lines for determining register values,

Fig. 6

an extension of the measuring field blocks according to FIG. 5,

Fig. 7

a variant of a measuring field block with integrated lines,

Fig. 8

2 with integrated lines, but without color strips,

Fig. 9

a variant of the measuring field block according to Fig. 8 and

Fig. 10

2 with integrated lines.

The measuring field shown in FIG. 1 comprises a color measuring surface F with lateral ones Color strips S. In the exemplary embodiment, the color measuring surface F has the shape of a square. One of the narrow, rectangular ones runs parallel to the edges of each of the four square sides Color stripes S. On the one hand, between the edges of the color measuring surface F that delimit and the lateral color stripe S on the other hand, a color-free zone Z, i.e. a Zone Z, at least in the printing of the measuring field, is formed, its width and so that the area is exactly specified at the ideal pressure. By comparing this ideal area the zone Z with the measured partial area of the area not printed in the actual print In zone Z the shift and duplication values of this pressure can be determined. Doing so it is sufficient to determine the sliding and duplication in the circumferential and lateral directions, to provide two color strips S at an angle to each other. The two others Color strips S then only amplify the measurement signal in an advantageous manner.

The minimum size of the color measuring area F is determined by the grid size of the printing process, i.e. the grid point size taking into account the available camera resolution or the spatial resolution of the sensor and a sufficiently meaningful statistic given.

The color measuring area F, which is square in the exemplary embodiment, can be straight within the plugged frame basically only rectangular and basically even arbitrary, but predetermined in a defined manner. The color stripes S do not necessarily have to run parallel to the edge, but the color-free zones Z must likewise, provided that the ideal pressure is present, it must be defined by its borders. However, the shape of the measuring field shown facilitates the actual probing analysis of the measurement results of the measuring field. This is also suitable Form especially for the combination of several such measuring fields into one compact measuring field block.

Such a compact measuring field block is shown in FIG. 2. It exists in the exemplary embodiment from twelve measuring fields, which are combined into a 3x4 grid-like measuring field block are. The individual measuring fields are labeled Al to D3.

The compact measuring field block for multi-color printing in general, i.e. for one any number of basic colors, Fig. 2.1 shows. An exemplary measuring field block for 8-color printing is finally shown in Fig. 2.2. The following is only always refer to the measuring field block of FIG. 2 for four-color printing, for example taken.

Two adjacent measuring fields Al to D3 collide with each other in the compact measuring field block their side stripes S blunt or with a predetermined distance in size from "a" to each other, if ideally there are no register deviations in the print occur. Two measuring fields, which are printed side by side so that their are each other facing color strips 3 have the narrow spacing a from each other are shown in Fig. 2.3 shown. In the case of an ideal register, a should be between 0 and a maximum of 400 micrometers lie. One between the side edge of the measuring surface F and the neighboring one Strip S formed distance is advantageously not more than 0.3 mm and is in Embodiment about 0.1 mm, so that on the one hand the measuring field is small Has dimensions, but still pushing and / or duplicating in full Extent can be determined.

In the measuring field block of FIG. 2, measuring field A1 is indicated by a solid tone field in black educated. The measuring field A2 is a grid in which the color black with its nominal area coverage is printed. The measuring field B1 is a Combination measuring field, in which the three primary colors cyan, magenta and yellow each with their nominal area coverage are printed on top of each other. The measuring fields A3, B2 and C1 are represented by single color grids with nominal area coverage in these three primary colors. The three are in the measuring fields B3, C2 and D1 Basic colors printed in full tone individually. For the remaining measuring fields C3, Finally, D2 and D3 are further combination measuring fields, in each of which two of the primary colors with nominal area coverage are printed on top of each other. The color black can also be used as the base color, i.e. as the fourth basic color, be designated.

In newspaper printing as a preferred example of use, the measuring fields A1 to D3 each have an extent of approximately 1.65 x 1.65 mm ² and the compact measuring field block with twelve such measuring fields has an extent of 6.6 x 5 mm ² . The miniaturized measuring fields designed in this way are also printed in selected image areas or, as shown, as a compact measuring field block on a printed product to be checked and then recorded inline, online or offline using a CCD color camera mounted on a microscope. The picture could also be taken at one or more image points using a photoelectric sensor with spectral and two-dimensional spatial resolution.

The captured images are digitized and then software using a feature-specific algorithm evaluated directly. The data can also be saved in the individual colors separated and the binary image thus generated with a corresponding feature-specific mathematical algorithm can be evaluated. A combination both methods are also possible.

In the exemplary embodiment, the color strips S of the measurement fields B3, C2, D1 and A1 serve Determination of the register of cyan, magenta, yellow and black in circumferential and in Side direction. Starting from the cyan measuring field B3, the relative positions of the Measuring fields C2, D1 and A1 for magenta, yellow and black and thus any register deviations determined. Pushing and duplicating is determined by the fact that on these Measuring fields each the unprinted zone Z between the color measuring areas F and the Color strip S is measured.

The color measuring areas F of the same measuring fields B3, C2, D1, A1 are used for the determination the solid density of the corresponding colors.

With the help of the measuring fields A2, C1, B2 and A3, the area coverage of black, Yellow, magenta and cyan determined. The register and shift as well as duplication values could can also be determined using these single-color grids.

The measuring fields C3, D3 and D2, in each of which two of the three primary colors yellow, magenta and Cyan are printed one above the other in grid tone and the measuring field B1, in which all three of these Basic colors are printed on top of each other in a grid tone, serve to determine the Color values and the color acceptance in the two and three-color overprint.

The targeted combination of individual measuring fields can be used for pushing and duplicating and generate the register qualitatively amplified signals, e.g. B. by the combination of Measuring fields B1, C1 and D1 for the basic color yellow, with B2, C2 and D2 for the basic color Magenta.

A preferred image processing comprises a photoelectric sensor with spectral and two-dimensional spatial resolution and image analysis hardware and software that in principle, however, can also be formed by hard-wired hardware, and a digital computer, preferably a personal computer. For the recorded signals the relevant image points of the compact Measurement blocks selected and the recorded signals, for example by means of Matrix operations in XYZ values and subsequently in LAB values and density values transformed.

For the determination of the surface coverings and the register, those are recorded Signals separated into binary images and then using a feature-specific Algorithm evaluated.

By printing the compact measuring field block according to FIG. 2 you can use the image analysis for evaluating the measurement data or the recorded image by means of a the only probing process in the smallest space in the type area that for product qualification and if necessary, features required for a diagnosis on the printed product are determined will. In an extremely short time, the extraction of an extraordinarily large number of Quality characteristics possible.

In the example shown for four-color printing, the compact can be touched per touch Measurement field blocks six register values, four full tone density values, four dot gain values, three Ink acceptance values for the basic colors, four shift and duplication values and four Color locus vectors and four color distances of the secondary and tertiary chromatic colors, in total that is, 29 measured or characteristic values can be determined.

Figures 3 and 4 show decision trees, following them based on the won Quality data a diagnosis is made. Based on these decision trees there is also one Optimization of color reproduction possible in multi-color print runs. The illustrated Decision trees can be refined by adding more quality data, such as the color values of the primary colors, data on ink and water flow on the printing press, Color material temperature, air temperature and humidity or image data of the printed subjects are included.

In general, it should be noted that color deviations by adjusting the color and / or Dampening solution guidance on the printing press can be corrected. Alternatively or In addition, it is possible to selectively produce the color separations in prepress Make corrections to the area coverage (tonal value compensation). While the adjustment of the printing press also to compensate for short-term fluctuations which offers color rendering, tonal value compensation is suitable in prepress for the correction of systematic or long-term fluctuating color deviations.

With regard to preferred measuring fields and methods for such corrections, DE 44 02 784 A1 and DE 44 02 828 A1 with reference.

Therefore, when generating a diagnosis based on the quality data collected distinguish between these two strategies. These are two Decision situations, namely on the one hand to optimize the color rendering in a single edition and on the other hand to optimize the color rendering several editions. 3 shows a decision tree for printing accordingly several editions. 3 shows a decision tree for printing accordingly one edition and FIG. 4 a decision tree for printing several editions.

The branches represent random points. Each branch is based on the determined quality data decided on which path further to the right is preceded. There are both exclusive branches, each of which only a further path should be followed, and not exclusive Branches where progress is possible on more than one continuing path is. When optimizing the color rendering over several editions (Fig. 4) it can occur that a color deviation due to a disturbance of the tone value increase and a Trapping disorder is caused. In this case, both the color deviation causing rheology problem and trapping disorder, i.e. it is a non-exclusive branch at the random point.

In the event of a fault, each path in the decision tree ends with a on the right Recommended action. Depending on the situation, there is a correction of the color and the Dampening solution management or a combination of both corrections, the correction of one color material-related rheology problem, rectifying a trapping disorder, rectifying of pushing or duplicating, the recalibration of the printing characteristics of the individual colors or recalibrating the color profile in terms of color management.

The decision trees according to FIGS. 3 and 4 are read in the pseudocode as follows:

A further differentiation of the recommendations for action is also possible. So can for example, the request to fix pushing or duplicating with an indication of possible causes, e.g. on the web tension, paper properties or the properties of rubber blankets.

Both decision trees shown as examples show how effective and Meaningful data compression automatically a quality assessment and, in the case too large deviations, a diagnosis combined with a recommendation for action is generated becomes. This is not enough, for example the known ones for each characteristic circulation-related statistical parameters such as minimum, maximum, mean and Automatically calculate and output scatter.

By using measuring fields according to the invention or compact measuring field blocks or It is a combination of these in combination with image analysis and decision tree possible, the conventional tools of the based on densitometry and colorimetry Optimization of color reproduction with the new tools of color management to unite an overall system.

If the quality data is very noisy, i.e. practically only random deviations contain a recommendation for action can no longer be clearly derived. In In this case, measurements are continued or additional quality data are used. An example is the situation where there are color fluctuations over several editions occur in multicolored overprinting that are not reproducible. It will then further editions printed and measured.

As an alternative to the decision tree, you can use it to derive the diagnosis and the Recommendations for action also include neural networks or unsharp logic algorithms (Fuzzy logic) or a combination thereof. Especially the neural Networks have the advantage that they can be trained using test patterns.

If the correct recommendations for action are known for each set of quality data, can provide such a network with the expert knowledge necessary to create a diagnosis are conveyed without sharp target values or tolerances in the must be determined in advance. Such an approach comes very close to the fact contrary, the numerical expert knowledge rather in a blurred than in a sharp form is present.

5 shows two measurement field blocks with integrated lines L. Each of the two Measuring field blocks have two in the circumferential direction of a printing cylinder one behind the other or in Measuring fields A1 and A2 arranged next to one another in the longitudinal direction of the printing cylinder. For example, the two measuring fields A1 and A2 can be two full-color single-color fields or trade two single-color grids in two different primary colors. The measuring fields A1 and A2 can each be of the type of the measuring field according to FIG. 1, i.e. be formed with a color measuring surface F and lateral color strips S. You can however, it can also be designed as a pure color measuring surface F without lateral color strips.

The two measuring field blocks according to FIG. 5 contain in addition to those of FIGS. 2 to 2.3 two groups of lines L. One group of lines L points circumferentially and the other transverse to it in the longitudinal direction of the impression cylinder, i.e. in the lateral direction.

In the left measurement field block in FIG. 5 there are two lines for the circumferential register and the Page register provided. In the case of two-color printing, the four lines L des are sufficient left measuring field blocks already completely for determining register deviations in Circumferential and lateral direction. One of the two is in the circumferential direction and one of the two lateral lines L in the reference color and the other Line printed in the further basic color to be coordinated. From the survey the distance between the two running in the same direction Lines L, generally the area enclosed between these two lines L. measured, the register deviation, i.e. the register, definitely.

The right-hand measurement field block of FIG. 5 shows in FIG A third line L on the circumferential direction. Of the three circumferential Lines L are two printed in the reference color and the third in the other basic color. In the lateral direction there are again only two lines L, one for the reference color and one for the further basic color. By for the reference color in the circumferential direction Two lines L printed in the measuring field block can be used independently of the measuring device the measurements can be compared using the evaluation method. The Method "white" due to the two lines L in the reference color, i.e. because of the Reference measurement, how strong the measured values recorded for the other basic color deviate from the nominal value.

5 represent minimal configurations, in the sense that that to determine a register deviation at least two lines L in for each Direction in which a register deviation is to be determined are included. It can are the only two primary colors in the case of two-color printing or but by any two primary colors, if more than just two different ones in the print Primary colors are used. In the latter case, there would be several measurement field blocks in the 5 required to the register values or register deviations for all to determine the primary colors used.

FIG. 6 shows an expansion of the measuring field blocks shown in FIG. 5. With the measuring field block 6, all register values can already be printed in four directions in the lateral direction are determined if of the lines L drawn in FIG. 6 in the lateral direction in each of the four primary colors, including black, at least one line L is provided.

If the measuring field block according to FIG. 6 is a measuring field block for a two-color printing are two of the five measuring fields shown as single color solid tone fields, two more as single color grid fields, in particular halftone fields, and the fifth field is designed as a suitable combination measuring field. The measuring field block 6 would therefore already have all the register values of interest in two-color printing and a wealth of densitometric and colorimetric values with a single touch deliver. Furthermore, in this case there are at least two lines in both directions L printed in the reference color.

5 and 6 between adjacent measuring fields In each case, narrow, pressure-free strips of width b remain, through which with an exact register The lines L run in the middle, are the measuring fields in the measuring field block according to FIG. 7 moved so far that, assuming exact registration, they are blunt or connect flush to the lines L running between them. It remains with Measuring field block according to FIG. 7 no pressure-free area between measuring fields A1 to C2.

This can save measuring block area again, but the noise component increased in the measurement signal compared to the measurement field blocks of Figures 5 and 6.

The distance b between two adjacent measuring fields is ideally approximately 0.5 mm with about 0.1 mm wide lines L, i.e. the distance between the lines L and neighboring measuring fields is then approximately 0.2 mm. The distance b should not be more than about 1 mm and should be as possible to obtain noise-free measurement signals can also be no less than about 0.1 mm.

FIG. 8 shows a measuring field block with integrated lines L, the measuring fields A1 to D3 have the same color assignment as that of the measuring field block according to FIG. 2. Indeed are the measuring fields A1 to D3 of the block according to FIG. 8 only as color measuring fields F. executed, i.e. A1 to D3 have no lateral color stripes S. In the measuring field block At least one line L for each of the two is integrated for each of the printing inks Directions in which the register deviations are to be determined. In one of the Both directions can be shown in the arrangement of a 3 x 4 measuring field block in the Measuring field block saves five lines L and four lines L in the other direction be provided so that two of the lines L in. running in one of the two directions the reference color can be printed. Additional lines could, for example, between adjacent lines L may be provided. Such an additional line L is indicated by dashed lines in FIG. 8.

As a further embodiment variant, a measuring field block is shown in FIG. 9, in which the Measuring fields A1 to D3, provided that the register is exact, meet immediately. The Lines L run across the measuring fields A1 to D3. The measuring field block according to FIG. 9 On the one hand, the measurement value signals for determining the register deviations are particularly compact however contain comparatively high noise components, which are caused by corresponding Evaluation methods are to be filtered out.

10 finally shows a measuring field block, the measuring fields A1 to D3 of which the Measuring field blocks according to FIG. 2 correspond exactly. However, they are adjacent to each other Measuring fields are evenly spaced from each other with an exact register so that Pressure-free strips remain between the measurement field columns and rows. Preferably all of these rectilinear strips have the same width b. Within the The integrated lines L run without pressure to determine the register deviations the two other primary colors to the reference color; preferably run them through the middle of the strips. 10 corresponds to that of FIG. 8, but with the difference that in addition to the lines L, the individual measuring fields A1 to D3 have lateral color stripes S, i.e. each individually with different color assignments correspond to the measuring field of FIG. 1.

In the measuring field block of FIG. 10, the lines L are preferably used to determine the Register values and the lateral color stripes S preferably for determining sliding and / or duplication values.

In the measurement field blocks of FIGS. 5 to 10, both the measurement fields and the Lines L each have a grid, its rows and columns or its lines in the circumferential direction and point in the lateral direction. The two grids are placed one on top of the other. Furthermore are the lines L in the circumferential direction and also in the lateral direction parallel and equally spaced arranged to each other. Other arrangements of the lines L are fundamental possible, the exact alignment in the circumferential and lateral direction and also the parallelism and spacing equality is preferred, however. In the specific case of use however, deviations from each of these individual characteristics.

Claims (17)

Measuring field block for recording quality data in multi-color production printing, the measuring fields (A1-D3) optically scanned on a printed product, each with at least one color measuring surface (F) for determining a color density, an area coverage or a color value for each of the measuring fields (A1-D3) having,
characterized in that
the measuring field block has lines (L) in primary colors used for printing for the simultaneous determination of values for a register deviation. Measuring field block according to claim 1, characterized in that at least one of the Lines (L) between at least two adjacent measuring fields (A1-D3) of the Measuring field blocks runs. Measuring field block according to the preceding claim, characterized in that immediately on both sides of the at least one line (L) to the adjacent to each this line (L) arranged measuring fields (A1-D3) at least with an exact register an unprinted, strip-shaped surface remains. Measuring field block according to one of the preceding claims, characterized in that that at least one line (L) through at least one of the measuring fields (A1-D3) of the Measuring field blocks runs. Measuring field block according to one of the preceding claims, characterized in that that in each of the primary colors of the print at least one line (L) for at least a direction in which a register deviation is to be determined is provided. Measuring field block according to one of the preceding claims, characterized in that that at least two lines (L) for at least one direction in which a register deviation is to be determined, is provided. Measuring field block according to one of the preceding claims, characterized in that that the lines (L) are spaced parallel into a first and an exact register have a perpendicular second direction, in each of the two directions at least one line (L) is provided in each of the primary colors. Measuring field block according to one of the preceding claims, characterized in that that the measuring fields (A1-D3) for the simultaneous acquisition of register and / or Shift and / or duplication values at least one lateral color stripe (S) have the same print together with the color measuring surface (F) of his Measuring field (A1-D3) is printed in relation to the dimensions of the color measuring area (F) of its measuring field (A1-D3) is narrow and in a predetermined, also in With regard to the dimensions of this color measuring surface (F), there is a small lateral distance to the Color measurement area (F) runs. Measuring field block according to the preceding claim, characterized in that the Measuring fields (A1-D3) at least two lateral color strips (S) for determining the Have sliding and duplicating in the circumferential and lateral directions. Measuring field block according to claim 8 or 9, characterized in that the color measuring surface (F) and the color stripe (S) of the same measuring field (A1-D3) by one color-free zone (Z) are separated from each other. Measuring field block according to one of claims 8 to 10, characterized in that the Color stripes (S) in a straight line parallel to the color measuring surface (F) of its measuring field (A1-D3) runs. Measuring field block according to one of the preceding claims, characterized in that that the color measuring surfaces (F) and the color strips (S) are rectangular. Measuring field block according to one of the preceding claims, characterized in that that the color measuring surfaces (F) have a color strip (S) near each of their edges. Measuring field block according to one of the preceding claims, characterized in that that the measuring fields (A1-D3), provided exact circumferential and lateral register, with their lateral color stripes (S) butting or closely spaced in form a compact measuring field block at a predetermined distance (a). Measuring field block according to one of the preceding claims, characterized in that that as measuring fields (A1-D3) single-color full-tone fields (B3, C2, D1) in the Basic colors (cyan, magenta, yellow, black) are provided. Measuring field block according to one of the preceding claims, characterized in that that individual color grid fields (A3, B2, C1) are provided as measuring fields (A1-D3), in each of which one of the basic colors (cyan, magenta, yellow, black) with their nominal area coverage is printed. Process for the acquisition of quality data in multi-color production printing, in which a) color measuring fields (A1-D3) comprising at least single color measuring fields (B3, C2, D1) in the basic colors (cyan, magenta, yellow), each having at least one color measuring surface (F) suitable for obtaining color values or color density values or area coverage and lines ( L) are printed in the basic colors (cyan, magenta, yellow, black) on a printed product, b) the measuring fields (A1-D3) and the lines (L) are optically scanned and c) the remitted light is evaluated, characterized in that d) the measuring fields (A1-D3) and lines (L) are printed in a common measuring field block.

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