EP0408507B1 - Méthode de détermination des écarts de couleur entre deux surfaces tramées imprimées avec une machine d'impression ainsi que méthode de commande ou réglage de l'impression couleurs d'une machine à imprimer - Google Patents

Méthode de détermination des écarts de couleur entre deux surfaces tramées imprimées avec une machine d'impression ainsi que méthode de commande ou réglage de l'impression couleurs d'une machine à imprimer Download PDF

Info

Publication number
EP0408507B1
EP0408507B1 EP90810513A EP90810513A EP0408507B1 EP 0408507 B1 EP0408507 B1 EP 0408507B1 EP 90810513 A EP90810513 A EP 90810513A EP 90810513 A EP90810513 A EP 90810513A EP 0408507 B1 EP0408507 B1 EP 0408507B1
Authority
EP
European Patent Office
Prior art keywords
tone
full
colour
differences
color
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP90810513A
Other languages
German (de)
English (en)
Other versions
EP0408507A1 (fr
Inventor
Hans Ott
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Gretag AG
Original Assignee
Gretag AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Gretag AG filed Critical Gretag AG
Publication of EP0408507A1 publication Critical patent/EP0408507A1/fr
Application granted granted Critical
Publication of EP0408507B1 publication Critical patent/EP0408507B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41F—PRINTING MACHINES OR PRESSES
    • B41F33/00—Indicating, counting, warning, control or safety devices
    • B41F33/0036—Devices for scanning or checking the printed matter for quality control
    • B41F33/0045—Devices for scanning or checking the printed matter for quality control for automatically regulating the ink supply
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41P—INDEXING SCHEME RELATING TO PRINTING, LINING MACHINES, TYPEWRITERS, AND TO STAMPS
    • B41P2233/00—Arrangements for the operation of printing presses
    • B41P2233/50—Marks on printed material
    • B41P2233/51—Marks on printed material for colour quality control

Definitions

  • the invention relates to a method for determining the color difference between two screen fields printed with the aid of a printing press according to the preamble of independent claim 1.
  • the invention relates to a method for color control or color regulation of the printing of a printing press according to the preamble of independent claim 2.
  • Methods for determining the color difference are generally used for quality assessment of printed products and require the use of color measuring devices or spectrophotometers in order to determine the coordinates assigned to a grid field, in particular a gray balance field, in a color space.
  • the use of such devices is perceived in many cases as expensive and complex because of the high optical and electronic complexity. It is also known to carry out a quality assessment on the basis of measured densitometric quantities.
  • a quality assessment based on a densitometric measurement system or densitometric parameters has the advantage that cheaper devices, namely densitometers can be used instead of spectrophotometers, but densitometric sizes are not particularly practical for a quality assessment and are not equivalent the sizes that occur in a real color measurement system.
  • the use of densitometers is limited to a densitometric measuring system which is worse for a quality assessment than color mass numbers in a color space that is equally sensitive in terms of sensibility, such as the L * a * b * color space or LUV color space.
  • EP-A-228 347 and EP-A 321 402 a method for color control and Color control of a printing press is known, in which measuring fields are scanned with the aid of a color measuring device or a spectrophotometer in order to obtain color coordinates in a colorimetric measuring system and, by means of a coordinate comparison from the color distance of the scanned measuring field from a predetermined target color location, a manipulated variable for adjusting the color guide elements of the printing machine to create.
  • the procedure according to EP-A-321 402 is such that a predetermined target color location lying outside a correction color space is replaced by an attainable target color location on the surface of the correction color space with a color distance from the predetermined target color location, which is for the Print quality essential components are minimal.
  • EP-A-255 924 discloses a method for controlling or regulating the color control of a printing press, in which a color change vector is determined from the target / actual color density deviations of the colored partial colors measured with the aid of a densitometer, from which a color change vector is then determined "Control recommendations" or “Regulation recommendations” for the color control are derived in a manner that is not described in detail.
  • the multiplication factors used in the "vectorial auxiliary construction" are determined by previous test prints with systematic variation of the coloring of the individual colors and subsequent evaluation using a densitometer and color measuring device.
  • the method disclosed in this document essentially only allows qualitative statements about the color deviations between the measured production print and the corresponding reference, since the "vector auxiliary construction" on which it is based, even with the most accurate density measurement, leads to mean errors of up to 16 ° in the polar angle and 3 delta-E -Units in the color difference leads. Although these errors are described as being sufficiently small to obtain sufficient information about the type and extent of a color cast for control processes, precise and reliable quantitative control of the color guide is not possible with this method.
  • the method according to this document is also relatively cumbersome and complicated insofar as the use of a multicolored overprint field (gray balance field) as a color control field means that the color density differences measured on it before Further processing by means of the "vectorial auxiliary construction" must first be "unmasked", ie the density value differences between the measured actual measured values and the target measured values of a target specimen must be converted using a linear system of equations into such density value differences as would have resulted from single-color prints. An additional series of test prints is required to determine the coefficients of the linear system of equations.
  • the invention has for its object to improve a method for determining the color difference and a method for color control or color control of the printing of a printing press of the generic types in such a way that a more precise determination of the color numbers in the selected color space and thus a more precise and reliable control or regulation of the Ink guide elements of the printing press is possible.
  • the invention is based on the knowledge that transformation matrices exist within small areas around a given color location in a colorimetric coordinate system, which make it possible to convert changes in color measures into changes in screen densities and in changes in solid densities of printed solid fields.
  • a third relationship consists in a transformation of changes in solid density of solid fields and changes in screen density of printed fields. If two transformations of the three transformations mentioned are known, the third can easily be calculated.
  • Fig. 1 four calibration prints or calibration cards with calibration color areas are shown schematically.
  • the calibration plate or calibration card shown below in FIG. 1 and produced under nominal pressure conditions is referred to below as reference calibration pressure 1.
  • the reference calibration print 1 has a color measuring strip or a calibration color area with four fields, of which the first a grid field 2, the second a cyan solid field 3, the third a magenta solid field 4 and the fourth a yellow or yellow solid field 5 is.
  • the grid 2 consists of three rasters printed one above the other with the colors and layer thicknesses of the solid tone fields 3 to 5, it being particularly expedient to use a gray balance field whose tone value or gray level is sensitive to layer thicknesses Changes and color is similar to a grid, as it occurs in the color measurement strip in the printed product to be produced later.
  • the raster field 2 of the reference calibration print 1 can be a dark gray gray balance field.
  • the screen 2 and the solid fields 3, 4 and 5 of the reference calibration print 1 are measured densitometrically .
  • the cyan grid density CR0, the magenta grid density MR0 and the yellow grid density YR0 are obtained for the grid field 2.
  • the three reference calibration measurement values for the three full tone densities and the three reference calibration measurement values for the screen densities are stored for comparison with other calibration prints in a memory, in particular in a memory of the densitometer or a memory of a connected computer or as a printout on a sheet of paper.
  • the grid 2 of the reference calibration print 1 is used in addition to the densitometric measurement of the densitometer can also be measured colorimetrically using a spectrophotometer.
  • the colorimetric measurement values recorded by the spectrophotometer are color measures of a color space, the L * a * b * color space (CIE 1976) preferably being used.
  • the L * a * b * color space is a color system with equally spaced sensations, the color dimensions of which are particularly useful for quality assessment in the color space, since they lead to greater flexibility and meaningfulness than solid color densities or screen densities.
  • Another color space system that can be used is the LUV system.
  • the colorimetric quantities or color dimension numbers L0, a0 and b0 are thus recorded and also stored for comparison with the values of other calibration prints.
  • This storage takes place electronically in the spectrophotometer itself or in a computer connected to it. It is also possible to save the color measure numbers as a printout, in particular as a printout on the reference calibration print 1 itself.
  • the additionally required calibration prints shown in FIG. 1, which are constructed similarly to the reference calibration pressure 1, are a first additional calibration pressure 6, a second additional calibration pressure 7 and a third additional calibration print 8.
  • the fields of the additional calibration prints 6 to 8, like the fields 2 to 5 of the reference calibration print 1, were each printed in such a way that the layer thicknesses of the differently colored full-tone fields match the layer thicknesses of the individual screen dots of the three printed on top of one another different colored grids of the respective grid are assigned.
  • the first additional calibration print 6 differs from the reference calibration print 1 in that a greater layer thickness of the ink guide elements of the printing machine has been set when printing the cyan solid-color field 9 and thus the associated cyan screen printed in the screen field 12, so that the solid cyan field 9 gives a larger solid cyan density CV1 than for the solid cyan field 3.
  • the magenta solid field 10 of the first additional calibration pressure 6 has a magenta solid density MV1, which corresponds to the solid density MV0 within the pressure tolerances.
  • the printed screen 12 of the first additional calibration print 6 differs from the screen 2 due to the greater layer thickness for the printing ink cyan in that the screen dots of the cyan screen each have a higher layer thickness.
  • the grid density is CR1 Grid 12 a higher measured value when measuring with the densitometer than was the case when measuring grid 2.
  • the magenta screen density MR1 of the screen 12 of the first additional calibration print 6 corresponds essentially to the magenta screen density MR0 of the reference calibration print 1. The same applies to the yellow screen density YR1 of the first additional calibration print 6.
  • the three measured values for the solid densities of the solid fields 9, 10 and 11 as well as the measured values of the halftone densities of the halftone field 12 of the first additional calibration print 6 are stored and used to compare the deviations of these six measured density values with respect to the corresponding measured six density values of the reference calibration print 1 to determine.
  • ⁇ CV1 0.19
  • ⁇ MV1 -0.01
  • ⁇ YV1 -0.02
  • ⁇ CR1 0.09
  • ⁇ MR1 0.04
  • ⁇ YR1 0.01
  • ⁇ L1 -1.85
  • a second additional calibration print 7 is shown together with the associated solid fields 13, 14 and 15 and the screen 16 also printed.
  • the same environmental conditions, in particular the same paper, printing ink and printing press were used as when printing the reference calibration print 1 and the first additional calibration print 6.
  • the second additional calibration print 7 has a much greater layer thickness for the magenta printing ink and thus a full tone density of the solid tone field 14 which is larger by ⁇ MV2 than the solid tone density MV0 of the solid tone field 4 of the reference calibration print 1.
  • the change in solid tone density ⁇ MV2 can be 0.26, for example.
  • a third additional calibration print 8 is finally produced, the layer thickness for the printing ink yellow or yellow being increased considerably in the solid field 19 shown at the top right in FIG. 1.
  • the resulting increase in solid density ⁇ YV3 can be, for example, 0.16.
  • the additional calibration prints 6, 7 and 8 differ from the reference calibration print 1 in that a full-tone density differs comparatively strongly by changing a layer thickness Lich has been made, while the other two colors have largely been left unchanged in their layer thicknesses.
  • the changes in the solid ink density there are changes in the grid field that is also printed, which, in contrast to the solid tone fields, is measured not only densitometrically but also colorimetrically as part of the calibration process.
  • FIG. 2 illustrates the concept on which the method according to the invention is based.
  • Fig. 2 on the left you can see three solid tone fields 21, 22, 23 of a color measuring strip or calibration print with the changes in the associated solid density densities ⁇ CV, ⁇ MV and ⁇ YV measured with the aid of a specific densitometer, which can be understood as the components of a three-dimensional solid density change vector [ ⁇ V].
  • These changes also cause changes in the grid field 24, 24 ', which is drawn twice on the right in FIG. 2, which can in particular be a gray balance field for monitoring the color balance of cyan, magenta and yellow in the overprint, the changes which can be detected by densitometry Screen densities are ⁇ CR, ⁇ MR and ⁇ YR.
  • an arrow 25 illustrates an assignment between the solid fields 21, 22, 23 and the grid field 24.
  • the connection of the solid fields 21 to 23 assigned full-tone density changes in a full-tone density space with the assigned raster density changes of the raster field 24 in a raster density space means a transformation of a three-dimensional vector, which can be represented by a full-tone density-raster density transformation matrix, which is hereinafter referred to briefly as transformation matrix [X].
  • the transformation matrix [X] has nine matrix elements and assigns the three solid density changes ⁇ CV, ⁇ MV and ⁇ YV to the three grid density changes ⁇ CR, ⁇ MR and ⁇ YR.
  • the transformation matrix [X] thus transforms the full-tone density change vector [ ⁇ V] formed from three full-tone density changes ⁇ CV, ⁇ MV and ⁇ YV into a screen density change vector [ ⁇ R] with the components ⁇ CR, ⁇ MR and ⁇ YR.
  • the transformation matrix [X] for three-dimensional vectors contains nine elements X11 to X33, which are the partial derivatives of the components of the grid density vector according to the components of the solid tone density vector. The following applies to the transformation matrix [X]:
  • an arrow 26 between the grid field 24 'and the solid fields 21 to 23 illustrates an assignment between changes in the color location assigned to the color of the grid field 24' in the L * a * b * color space or the assigned changes in the colorimetric values or Color measures on the one hand and the changes in solid density of the solid fields 21 to 23 printed on the other.
  • This corresponds to a transformation of a three-dimensional color change vector [ ⁇ F], the components of which are formed by the changes in color measure number ⁇ L, ⁇ a and ⁇ b, in the L * a * b * color space into the assigned three-dimensional full-tone density change vector ⁇ V in the full-tone density space.
  • the nine components of the matrix [Z] are formed in an analogous manner to the matrix [X] by the partial derivatives of the components of the solid density vector according to the components of the color vector.
  • FIG. 2 finally shows an arrow 27 between the grid field 24 'and the grid field 24.
  • the arrow 27 illustrates an association between changes ⁇ L, ⁇ a, ⁇ b of the colorimetric values L, a, b in L * a * b * - Color space of the grid field 24 'and the associated densitometrically detectable grid density changes ⁇ CR, ⁇ MR and ⁇ YR of the grid field 24 which is physically identical to the grid field 24'.
  • the assignment between three changes in color measures and three changes in grid densities illustrated by arrow 27 can be determined by a color measure - Describe the grid density transformation matrix.
  • the matrix ( briefly referred to as the transformation matrix [W], allows the transformation of the three-dimensional color change vector [ ⁇ F] in the L * a * b * color space into a grid density change vector [ ⁇ R] in the grid density space.
  • the transformation matrix [W] has nine elements because it transforms a three-dimensional vector into another three-dimensional vector.
  • the elements W11 to W33 are formed by the partial derivatives of the components of the vector [ ⁇ R] after the components of the vector [ ⁇ F]. The following therefore applies to the transformation matrix [W]:
  • the transformation matrices [X], [W] and [Z] can be assigned inverse transformation matrices [X ⁇ 1], [W ⁇ 1] and [Z ⁇ 1], respectively are illustrated by arrows 28, 29 and 30 in FIG. 2 and can each be used in a transformation in the opposite direction to the transformations illustrated by arrows 25, 27 and 26. It can be seen from FIG. 2 and the above explanations that it is sufficient to know two transformation matrices which are not inverse to one another in order to calculate any conversions between changes in the full-tone density space, screen density space and L * a * b * color space.
  • FIG. 3 illustrates how, in accordance with the method according to the invention, by measuring the calibration prints described in connection with FIG. 1, the transformation matrices [X], [W] and [Z] are determined for a working point predetermined, for example, by a gray balance field.
  • the solid fields 9, 10 and 11 known from FIG. 1 correspond to the trio of solid fields V1, the solid fields 13, 14 and 15 the trio of solid fields V2 and the solid fields 17, 18 and 19 the trio of solid fields V3.
  • the reference calibration print 1 is measured with the raster field R0 and the trio of solid fields V0.
  • a spectrophotometer 30 which allows the grid fields R0, R1, R2 and R3 to be measured colorimetrically.
  • a densitometric measurement of the grid fields R0 to R3 takes place with the aid of the densitometer 31 shown schematically in FIG. 3.
  • the spectrophotometer 30 delivers color dimensions L0, a0, b0 for the grid R0 of the reference calibration print 1, L1, a1, b1 for the grid R1 of the first additional calibration print 6, L2, a2, b2 for the grid R2 of the second additional Calibration print 7 and L3, a3, b3 for the grid R3 of the third additional calibration print 8. From the output 32 of the spectrophotometer, the triples of the color measures L i , a i and b i either go directly electrically or with the interposition of a display and manual keyboard input into a computer 33 assigned to the spectrophotometer 30 and the densitometer 31.
  • the difference calculator 34 stores the calculated difference values for the color measures, ie the numerical values for ⁇ L1, ⁇ a1, ⁇ b1, ⁇ L2, ⁇ a2, ⁇ b2, ⁇ L3, ⁇ a3 and ⁇ b3.
  • the grid fields R0, R1, R2 and R3 are additionally measured with the aid of the densitometer 31 in order to determine the grid densities for each of the colors cyan, magenta and yellow, so that the differences between the grid densities of the grid R1 are then determined in a difference calculator 35 for grid densities , R2 and R3 on the one hand and the grid density of the grid R0 on the other hand can be calculated.
  • the Grid density differences are available at the output of the difference calculator 35 for grid densities the following nine values: ⁇ CR1, ⁇ MR1, ⁇ YR1, ⁇ CR2, ⁇ MR2, ⁇ YR2, ⁇ CR3, ⁇ MR3 and ⁇ YR3.
  • the densitometer 31 is also used during the calibration measurements on the calibration prints also for the densitometric measurement of the full tone fields V0 of the reference calibration pressure 1, the full tone fields V1 of the first additional calibration pressure 6, the full tone fields V2 of the second additional calibration pressure 7 and the full tone fields V3 of the third additional calibration pressure 8.
  • These solid tone fields have the reference numerals 3, 4, 5, 9, 10, 11, 13, 14, 15, 17, 18 and 19 in FIG. 1.
  • the densitometer 31 is also directly electrically connected to a difference computer 36 for solid densities in the computer 33 or with the interposition of a densitometer display and a keyboard.
  • the difference calculator 35 for screen densities and the difference calculator 36 for solid tones feed as can be seen from the block diagram in FIG. 3, a first matrix calculator 37.
  • the matrix calculator 37 serves to determine the nine elements of the transformation matrix [X]. For this purpose, he receives from the difference computer 35 for the screen densities the nine numerical values for screen density differences mentioned above and from the difference computer 36 for full tone densities the above-mentioned nine measured values for full tone density differences.
  • the first matrix calculator 37 calculates the numerical values for the nine unknowns X11, X12, X13, X21, X22, X23, X31, X32 and X33. These numerical values are output by the first matrix computer 37 at the output 38 as the nine elements of the transformation matrix [X].
  • the computer 33 contains a second matrix computer 39 for calculating the transformation matrix [W].
  • the second matrix computer 39 supplies the nine elements of the transformation matrix [W] at its output 40.
  • the outputs 38 and 40 of the first matrix computer 37 and the second matrix computer 39 feed the two inputs of a third matrix computer 41, which it allows the transformation matrix [X] to be inverted and multiplied by the transformation matrix [W] in order to calculate the nine elements of the transformation matrix [Z] described in connection with FIG. 2.
  • the spectrophotometer 30 is no longer required in order to carry out a quality control and quality assessment in the L * a * b * color space with the densitometer 31.
  • the system consisting of the densitometer 31 and the computer 33 can now be placed by placing the densitometer 31 on a grid 43 similar to the grid of the calibration prints, in particular a gray balance grid of a sample sheet or OK sheet 44 (FIG. 4) determine the differences between the color measures of the grid 43 of the OK sheet 44 and the color measures of the grid 2 of the reference calibration print 1. After knowledge of these differences or deviations, it is possible, taking into account the color dimensions of the screen 2 of the reference calibration print 1 known from the measurement with the spectrophotometer 30, also to determine the absolute color numbers of the screen 43 of the OK sheet 44 without the OK -Bow 44 has been scanned with a spectrophotometer.
  • FIG. 4 shows the system consisting of the computer 33 and the densitometer 31 with a printing machine 42 which can be controlled with the aid of this system, as well as the OK sheet 44 and a production sheet 45 in a schematic representation.
  • the sample sheet or OK sheet 44 is drawn in FIG. 4, top left with its grid 43 which serves as a reference color area and which is similar in color to the grid 2 of the reference character print 1.
  • the color appearance of the raster field 43 becomes continuous with a raster field 46, in particular a corresponding gray balance field in the color measuring strip, when printing the production sheets 45, one of which is shown schematically with a color measuring strip in FIG. 4, top right compared.
  • the arrangement shown in FIG. 4 with the densitometer 31 and the computer 33 is used to check the continuous printing sheets 45 printed continuously with the printing machine 42 with regard to their color correspondence with the OK sheet 44 and to readjust the ink guiding elements of the printing machine 42 in the event of deviations .
  • a control variable is output at its output 47, which is fed as an input variable via the input 48 to the layer thickness control of the printing press 42.
  • the control signals present at input 48 are a layer thickness change control vector, the components of which are shown in FIG. 4 are.
  • the component ⁇ CV of the layer thickness change control vector specifies the amount by which the layer thickness for the printing ink cyan has to be changed in order to correct the color appearance of the grid field 46 if there is a deviation from the color appearance of the grid field 43 on the OK sheet 44. Accordingly, the components ⁇ MV and ⁇ YV of the layer thickness change control vector [ ⁇ V] are assigned to the required layer thickness changes for the printing inks magenta and yellow.
  • the densitometer 31 first serves to determine and to store the target value for the screen density vector [R] SOLL which can be obtained by measuring the screen field 43 of the OK sheet 44.
  • the actual value of the screen density vector [R] IST is measured with the aid of the densitometer 31 by measuring the grid field 46 in the color measurement strip of the printing sheet 45.
  • the computer 33 has a plurality of computing units designed in terms of hardware or software, which represent an evaluation computer which makes it possible, on the one hand, to determine a quality measure for the respectively printed production sheet 45 from the comparison of the vector [R] ACTUAL with the vector [R] SHOULD , which is available at the output 49 of the computer 33, and on the other hand to generate an input variable for the layer thickness control, which is provided at the output 47 of the computer 33.
  • the part of the computer 33 designated as the evaluation computer in FIG. 4 not only receives the measured values of the densitometer 31 as input variables, but also the matrix elements of the transformation matrices [X], [W] and [Z] determined beforehand on the basis of the calibration prints. These values reach the part of the computer 33 referred to as an evaluation computer via the inputs 50, 51 and 52.
  • the computer 33 has a screen density difference calculator 53 which calculates the deviations between the actual screen densities measured on the respective printing sheet 45 and the target screen density recorded on the OK sheet 44.
  • the output 56 of the grid density difference calculator 53 is connected to a first input 57 of a quality measurement calculator 54, the second input 58 of which is supplied with the values of the nine matrix elements of the transformation matrix [W].
  • the transformation matrix [W] is first inverted in the quality measurement computer 54 and then multiplied by the grid density difference vector [ ⁇ R].
  • the calculation results are available in the form of color measure difference ⁇ L, ⁇ a and ⁇ b, which can be viewed as the components of a three-dimensional color difference vector [ ⁇ F].
  • the quality measurement computer 54 has converted the deviations from density values into deviations from color coordinates of a color space that is equally graduated in terms of sensation. Based on the known deviations and the color dimensions for the calibration print or OK sheet, it is then also possible to determine the absolute color coordinates.
  • the grid density difference calculator 53 also feeds the first input 60 of a first layer thickness control computer 55.
  • the first layer thickness control computer 55 receives at its second input 61 the values of the elements of the transformation matrix [X] fed in via the input 50 of the computer 33.
  • the first layer thickness control computer 55 calculates the components ⁇ CV, ⁇ MV and ⁇ YV of the layer thickness change control vector [ ⁇ V], the values of which output from the output 62 of the first, from the product of the inverted transformation matrix [X] ⁇ 1 and the grid density difference vector [ ⁇ R] Layer thickness control computer 55 to the output 47 of the computer 33 and from there to the input 48 of the layer thickness control for the ink guide members of the printing press 42.
  • FIG. 4 Two further possibilities for the determination of the layer thickness change control vector are shown, whereby the interruptions 97, 98 and 99 in the drawn lines are intended to illustrate that an interruption 97, 98, 99 is bridged depending on the selected option.
  • the control strategy block 63 generates substitute color measure number differences ⁇ L ', ⁇ a' and ⁇ b 'from the color measure number differences fed in at the color measure number input 64, which are output via the output 65 and feed the first input 66 of the third layer thickness control computer 55 ′′.
  • the layer thickness change control vector which is present at the output 68 of the third layer thickness control computer 55 ′′ and is fed in when the interruption 99 is closed via the output 47 to the input 48 of the printing press 42 is changed or improved in accordance with the strategy defined in the control strategy block 63 in relation to a layer thickness change control vector as it is at the output of the layer thickness control computer 55 'is available.
  • a wide variety of strategies can be used as the control strategy for the control strategy block 63, in which color measure number differences are to be replaced by more useful color measure number differences.
  • a control strategy can be implemented in the control strategy block 63, which allows the highest possible print quality to be achieved even if the specified target color location in the color space lies outside a correction range which is limited as a result of maximum and minimum full-tone layer thicknesses.
  • the control strategy block 63 therefore has a limit value input 69 via which the boundary conditions, i.e. the minimum and maximum layer thicknesses that are permitted are entered.
  • the boundary conditions i.e. the minimum and maximum layer thicknesses that are permitted are entered.
  • the control strategy described here it is necessary to measure 45 additional solid tone fields 70, 71 and 72 densitometrically on the production sheet.
  • the solid field 70 is a solid field with the solid density CV for the color cyan.
  • the solid field 71 is a solid field with the solid density MV for the magenta printing ink and the solid field 72 is a solid field with the solid density YV for the color yellow or yellow.
  • the densitometer 31 when using the control strategy block 63, in addition to the densitometric measurement of the grid field 46, a densitometric detection of the full tone fields 70 to 72 is carried out in order to be able to determine within the control strategy whether an adjustment of the layer thicknesses would lead to the change in a layer thickness leads to an area that is no longer permitted.
  • the densitometer 31 is therefore additionally connected to an actual full-tone input of the control strategy block 63.
  • control strategy implemented in control strategy block 63 is described in detail in EP-A 321 402.
  • the color measure numbers of the are in the control strategy block 43 via an input, not shown in FIG Reference character print 1 has been entered so that, based on these color measure numbers and the color measure number differences at the color measure number input 64, the color location of the color of the grid 46 is available for carrying out the control strategy.
  • the color location of the raster field 43 of the OK sheet 44 results simply from the fact that, with the aid of the arrangement shown in FIG. 4, the reference character print 1 and the OK sheet 44 are measured densitometrically in succession.
  • the color locus of the grid field 43 of the OK sheet 44 results from the known color measure numbers of the reference character print 1 and the color measure number differences for the grid field 43 calculated with the aid of the evaluation computer of the computer 33.
  • By comparing the grid field 43 of the OK sheet 44 with the grid field 46 of the production sheet 45 finally results in the differences in the color measure between the grid 46 and the grid 43, so that ultimately not only the differences in color measures but also the absolute color measures or color coordinates in the L * a * b * color space are known for the grid 46.
  • the color coordinates in the color space determined in this way indicate an actual color location by which the control strategy block determines a correction color space for the colors that can be achieved on the basis of the predetermined limit densities for the solid fields 70 to 72 and the solid densities of the solid fields actually measured with the aid of the densitometer.
  • the predetermined target color location is replaced by an achievable target color location on the boundary surface of the correction color space with a color distance from the predetermined target color location, whose for the print quality essential components are minimal.
  • the color location on the surface of the correction color space that has the smallest color distance from the specified target color location is selected as the achievable target color location.
  • the position of the target color locus in the L * a * b * color space outside the correction color space spanned by the actual color locus in the L * a * b * color space there are various options for determining an optimal replacement target color locus according to Control strategy.
  • One possibility is that a solder is dropped from the predetermined target color location onto the adjacent side surface of the correction color space and the intersection point of the solder with the side surface is used as an attainable target color location.
  • the specified target color location adjacent corner of the correction color space is used as an attainable target color location.
  • chrominance errors are more critical than pure brightness errors (luminance errors). Therefore, according to an alternative of the control strategy, it is provided that the intersection of a parallel to the brightness coordinate axis closest to the predetermined target color location through the predetermined target color location with the surface of the correction color space is selected as the achievable target color location or replacement target color location.
  • the closest points on the surface of the correction color space as achievable target points for the points lying on a parallel to the brightness coordinate axis through the given target color location within a given brightness error range with a maximum and a minimum brightness. Color locations can be determined. It is possible that the closest point on the surface of the correction color space is determined for the point on the parallel) which is assigned to the largest acceptable brightness error.
  • the control strategy can also provide that the intersection of the color distance vector between the actual color location of the grid field 46 and the predetermined target color location of the grid field 43 with the surface of the color correction space is selected as the achievable replacement target color location.
  • measurement value processing is provided in which the color distance vectors between the target color location and the actual color location are multiplied by a sensitivity matrix in order to calculate the layer thickness change control vector which is the next time a production run is printed -Bogens 45 must be taken into account to achieve the desired color location shift.
  • the sensitivity matrix with which density differences for the color locus shift between the target color locus and the actual color locus are calculated, can be determined empirically and in terms of measurement technology using a test series in the control strategy mentioned.
  • control strategy can also be implemented in such a way that the control strategy block 63 does not have a layer thickness change control vector at the output 65, but only substitute color dimension difference 55 '' can be converted into a layer thickness control vector using the transformation matrix [Z].
  • Another particularly simple possibility for a control strategy in which the boundary conditions of the solid densities are taken into account, can be realized in such a way that the output of the second layer thickness control computer 55 'feeds a further input of the control strategy block 63 in a manner not shown in FIG. 4 in order to Avoid that 63 color measure number differences occur at the output of the control strategy block, which, after conversion in the third layer thickness control computer 55 ′′, would lead to an overriding of the ink guide elements beyond the layer thickness limit values.

Claims (6)

  1. Méthode de détermination des différences d'indices colorimétriques entre deux zones tramées imprimées à l'aide d'une presse à imprimer, en particulier deux zones d'équilibrage de l'échelle des gris, par exploration optique, à l'aide d'un densitomètre, des zones tramées à comparer, méthode dans laquelle, pour chaque couleur d'impression participante, on détermine la différence des densités de trame correspondantes et, par une transformation comprenant une multiplication, on transforme ces différences en différences d'indice colorimétrique sur un diagramme chromatique étagé à équidistance, sensible, méthode dans laquelle on détermine les facteurs de multiplication par un essai préalable d'impression avec variation systématique de l'apport des différentes couleurs, puis traitement au moyen d'un densitomètre et d'un appareil de mesure calorimétrique, méthode caractérisée par le fait qu'un vecteur de différence des densités de trame, comprenant comme composantes les différences des densités de trame des couleurs d'impression participantes, est transformé, par multiplication avec une matrice de transformation indices colorimétriques - densité de trame, inversée, en un vecteur de modification de couleur, comprenant comme composantes les différences d'indices colorimétriques, sur le diagramme chromatique étagé à équidistance, sensible, méthode dans laquelle la matrice de transformation indices colorimétriques - densité de trame est déterminée par le moyen qu'à l'aide de la presse à imprimer on imprime, sous les conditions nominales, un tirage étalon de référence ainsi que plusieurs tirages étalons supplémentaires, qui présentent chacun plusieurs zones de couleur pleine ainsi qu'une zone tramée, en particulier une zone d'équilibrage de l'échelle des gris, imprimée en même temps et semblable, au point de vue colorimétrique, aux zones tramées à comparer, méthode dans laquelle chaque tirage étalon supplémentaire présente, pour au moins une zone de couleur pleine, une densité de couleur pleine différente de celle de la zone de couleur pleine de même couleur du tirage étalon de référence, par le fait qu'à l'aide du densitomètre on mesure les différences de densité de trame entre les densités de trame de la zone tramée du tirage étalon de référence d'une part et celles des zones tramées des tirages étalons supplémentaires d'autre part, et qu'à l'aide d'un spectrophotomètre, on mesure les différences d'indices colorimétriques entre les indices colorimétriques de la zone tramée du tirage étalon de référence d'une part et ceux des zones tramées des tirages étalons supplémentaires d'autre part, par le fait qu'en utilisant les valeurs, saisies de cette façon, pour les différences de densité de trame et pour les différences d'indice colorimétrique, on détermine, dans les équations [ΔR]i = [W] ·[ΔF]i
    Figure imgb0069
     les éléments de la matrice de transformation [W] indices colorimétriques-densités de trame, étant précisé que [ΔR]i est le vecteur de différence de densité de trame qui correspond au tirage étalon supplémentaire d'ordre i et dont les composantes sont formées par les différences de densité de trame pour chaque couleur d'impression et que [ΔF]i est le vecteur de différence d'indice colorimétrique qui correspond au tirage étalon supplémentaire d'ordre i et dont les composantes sont formées par les différences d'indice colorimétrique.
  2. Méthode de commande ou de régulation de la couleur de l'impression d'une presse à imprimer, méthode dans laquelle, on saisit par voie optique les zones de mesure sur les feuilles imprimées par la machine à imprimer après démarrage, pour déterminer la distance colorimétrique entre la zone de mesure saisie et une position chromatique prescrite et, à partir de cette distance, produire une grandeur réglante pour régler l'organe de guidage de la couleur de la presse à imprimer, afin de rendre minimaux les écarts de couleur indésirables dans les feuilles imprimées ensuite après démarrage avec le nouveau réglage de guidage de la couleur, méthode dans laquelle en outre on prévoit, sur la feuille obtenue par impression après le démarrage, une zone de mesure, sous forme d'une zone tramée, en particulier une zone d'équilibrage de l'échelle des gris, constituée de plusieurs couleurs d'impression, à laquelle correspond, sur une feuille OK, une trame correspondante définissant la position chromatique prescrite, méthode dans laquelle en outre la détermination de la distance colorimétrique par comparaison des densités de trame obtenues lors de l'exploration des deux zones tramées à l'aide d'un densitomètre se fait de façon que, pour chaque couleur d'impression participante, on détermine la différence des densités de trame correspondantes et, par une transformation comprenant une multiplication, on transforme ces différences en un vecteur de modification de couleur sur un diagramme chromatique étagé à équidistance, sensible, étant précisé que les facteurs de multiplication sont déterminés par un essai préalable d'impression avec variation systèmatique de l'apport des différentes couleurs puis traitement au moyen d'un densitomètre et d'un appareil colorimétrique, et étant précisé qu'à partir du vecteur de modification de la couleur, obtenu de cette façon, on produit des recommandations de commande ou de régulation pour le réglage des organes de guidage de la couleur de la presse à imprimer, méthode caractérisée par le fait qu'un vecteur de différence des densités de trame, comprenant comme composantes les différences des densités de trame des couleurs d'impression participantes, est transformé, par multiplication avec une matrice de transformation indices colorimétriques - densité de trame, inversée, en un vecteur de modification de couleur, comprenant comme composantes les différences d'indices colorimétriques, sur le diagramme chromatique étagé à équidistance, sensible, méthode dans laquelle la matrice de transformation indices colorimétriques - densité de trame est déterminée par le moyen qu'à l'aide de la presse à imprimer on imprime, sous les conditions nominales, un tirage étalon de référence ainsi que plusieurs tirages étalons supplémentaires, qui présentent chacun plusieurs zones de couleur pleine ainsi qu'une zone tramée, en particulier une zone d'équilibrage de l'échelle des gris, imprimée en même temps et semblable, au point de vue colorimétrique, aux zones tramées à comparer, méthode dans laquelle chaque tirage étalon supplémentaire présente, pour au moins une zone de couleur pleine, une densité de couleur pleine différente de celle de la zone de couleur pleine de même couleur du tirage étalon de référence, par le fait qu'à l'aide du densitomètre on mesure les différences de densité de trame entre les densités de trame de la zone tramée du tirage étalon de référence d'une part et celles des zones tramées des tirages étalons supplémentaires d'autre part, et qu'à l'aide d'un spectrophotomètre, on mesure les différences d'indices colorimétriques entre les indice colorimétriques de la zone tramée du tirage étalon de référence d'une part et ceux des zones tramées des tirages étalons supplémentaires d'autre part, par le fait qu'en utilisant les valeurs, saisies de cette façon, pour les différences de densité de trame et pour les différences d'indice colorimétrique, on détermine, dans les équations [ΔR]i = [W] ·[ΔF]i
    Figure imgb0070
     les éléments de la matrice de transformation [W] indices colorimétriques-densités de trame, étant précisé que [ΔR]i est le vecteur de différence de densité de trame qui correspond au tirage étalon supplémentaire d'ordre i et dont les composantes sont formées par les différences de densité de trame pour chaque couleur d'impression et que [ΔF]i est le vecteur de différence d'indice colorimétrique qui correspond au tirage étalon supplémentaire d'ordre i et dont les composantes sont formées par les différences d'indice colorimétrique, et par le fait qu'à partir du vecteur de modification de couleur obtenu de cette façon on produit un vecteur de commande de modification d'épaisseur de couche pour le réglage des organes de guidage de la couleur de la presse à imprimer.
  3. Méthode selon la revendication 2, caractérisée par le fait qu'à l'aidee des densités limites prescrites et des densités de couleur pleine mesurées des zones de couleur pleine imprimées en même temps que la zone tramée sur les feuilles imprimées après démarrage, on détermine un espace chromatique correctif autour de la position chromatique réelle mesurée sur la zone tramée et par le fait que l'on remplace une position chromatique prescrite, située à l'extérieur de l'espace chromatique correctif, par une position chromatique prescrite, pouvant être effectivement atteinte, sur la surface de limitation de l'espace chromatique correctif, à une distance chromatique de la position chromatique prescrite dont les composantes essentielles pour la qualité de l'impression sont minimales.
  4. Méthode selon la revendication 2 ou 3, caractérisée par le fait que l'on multiplie le vecteur de modification de la couleur, ou bien un vecteur de modification de la couleur de remplacement calculé en fonction d'une stratégie de régulation sur le diagramme chromatique et en tenant compte des valeurs limites pour les densités de couleur pleine que l'on peut effectivement atteindre, par une matrice de transformation indices colorimétriques - densité de couleur pleine, pour obtenir le vecteur de commande de modification d'épaisseur de couche.
  5. Méthode selon la revendication 4, caractérisée par le fait que l'on détermine la matrice de transformation indices colorimétriques - densités de couleur pleine par le moyen qu'à l'aide du densitomètre on mesure, pour chaque couleur, une différence de densité de couleur pleine entre les densités de couleur pleine de la zone de couleur pleine du tirage étalon de référence, d'une part, et celles des zones de couleur pleine des tirages étalons supplémentaires d'autre part, et qu'à l'aide du spectrophotomètre, on détermine les différences d'indice colorimétrique entre les indices colorimétriques de la zone tramée du tirage étalon de référence d'une part et ceux des zones tramées des tirages étalons supplémentaires d'autre part, par le fait qu'en introduisant les valeurs, saisies de cette façon, pour les différences de densité de couleur pleine et pour les différences d'indices colorimétriques dans les équations [ΔV]i =[Z] ·[ΔF]i
    Figure imgb0071
     on détermine les éléments de la matrice de transformation [Z] indices colorimétriques - densité de couleur pleine, étant précisé que [V]i est le vecteur de différence de densité de couleur pleine qui correspond au tirage étalon supplémentaire d'ordre i et dont les composantes sont formées par les différences de densité de couleur pleine pour chaque couleur d'impression et que [ΔF]i est le vecteur de différence d'indice colorimétrique qui correspond au tirage étalon supplémentaire d'ordre i et dont les composantes sont formées par les différences d'indice colorimétrique.
  6. Méthode selon la revendication 4, caractérisée par le fait que l'on détermine la matrice de transformation indices colorimétriques - densité de couleur pleine par le moyen que l'on détermine la matrice de transformation [W] indices colorimétriques-densité de trame et qu'on la multiplie par la matrice de transformation densité de couleur pleine, densité de trame inversée [X]⁻¹ que, de son côté, on détermine par le moyen qu'à l'aide d'un densitomètre on mesure les différences de densité de trame entre les densités de trame de la zone tramée du tirage étalon de référence d'une part et celles des zones tramées des tirages étalons supplémentaires d'autre part, ainsi que, pour chaque couleur, la différence de densité de couleur pleine entre les densités de couleur pleine de la zone de couleur pleine du tirage étalon de référence d'une part et celles des zones de couleur pleine des tirages étalons supplémentaires d'autre part, par le moyen qu'en introduisant les valeurs, saisies de cette façon, pour les différences de densité de trame et pour les différences de densité de couleur pleine dans les équations [ΔR]i = [X] ·[ΔV]i
    Figure imgb0072
     on détermine les éléments de la matrice de transfor mation densité de couleur pleine-densité de trame [X], étant précisé que [ΔR]i est le vecteur de différence de densité de trame qui correspond au tirage étalon supplémentaire d'ordre i et dont les composantes sont formées par les différences de densité de trame pour chaque couleur d'impression et que [ΔV]i est le vecteur de différence de densité de couleur pleine qui correspond au tirage étalon supplémentaire d'ordre i et dont les composantes sont formées par les différences de densité de couleur pleine.
EP90810513A 1989-07-14 1990-07-05 Méthode de détermination des écarts de couleur entre deux surfaces tramées imprimées avec une machine d'impression ainsi que méthode de commande ou réglage de l'impression couleurs d'une machine à imprimer Expired - Lifetime EP0408507B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CH264689 1989-07-14
CH2646/89 1989-07-14

Publications (2)

Publication Number Publication Date
EP0408507A1 EP0408507A1 (fr) 1991-01-16
EP0408507B1 true EP0408507B1 (fr) 1993-11-10

Family

ID=4238429

Family Applications (1)

Application Number Title Priority Date Filing Date
EP90810513A Expired - Lifetime EP0408507B1 (fr) 1989-07-14 1990-07-05 Méthode de détermination des écarts de couleur entre deux surfaces tramées imprimées avec une machine d'impression ainsi que méthode de commande ou réglage de l'impression couleurs d'une machine à imprimer

Country Status (4)

Country Link
US (1) US5068810A (fr)
EP (1) EP0408507B1 (fr)
JP (1) JPH0356832A (fr)
DE (1) DE59003421D1 (fr)

Families Citing this family (48)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4005558A1 (de) * 1990-02-22 1991-09-19 Roland Man Druckmasch Verfahren zur prozessdiagnose einer rotationsdruckmaschine anhand von remissionen von vollton- und rastertonfeldern
JPH0514750A (ja) * 1990-10-16 1993-01-22 Sharp Corp 画像色分解装置
US5149960B1 (en) * 1991-07-03 1994-08-30 Donnelly R R & Sons Method of converting scanner signals into colorimetric signals
US5841955A (en) * 1991-12-02 1998-11-24 Goss Graphic Systems, Inc. Control system for a printing press
US5224421A (en) * 1992-04-28 1993-07-06 Heidelberg Harris, Inc. Method for color adjustment and control in a printing press
US5412577A (en) * 1992-10-28 1995-05-02 Quad/Tech International Color registration system for a printing press
US5357448A (en) * 1993-02-02 1994-10-18 Quad/Tech, Inc. Method and apparatus for controlling the printing of an image having a plurality of printed colors
JP3070027B2 (ja) * 1993-04-21 2000-07-24 富士通株式会社 配線基板の製造方法
US5508826A (en) * 1993-04-27 1996-04-16 Lloyd; William J. Method and apparatus for calibrated digital printing using a four by four transformation matrix
US5381349A (en) * 1993-06-29 1995-01-10 Hewlett-Packard Company System for calibrating a color display to enable color-matching
EP0632645A1 (fr) * 1993-06-29 1995-01-04 Schablonentechnik Kufstein Aktiengesellschaft Procédé de reproduction de motifs et pochoir pour ce dernier
EP0658428B1 (fr) * 1993-12-15 1999-08-11 Goss Graphic Systems, Inc. Système de commande d'imprimerie
DE4402784C2 (de) * 1994-01-31 2001-05-31 Wifag Maschf Messfeldgruppe und Verfahren zur Qualitätsdatenerfassung unter Verwendung der Messfeldgruppe
DE4402828C2 (de) * 1994-01-31 2001-07-12 Wifag Maschf Messfeldgruppe und Verfahren zur Qualitätsdatenerfassung unter Verwendung der Messfeldgruppe
NL193959C (nl) * 1994-03-08 2001-03-02 Stork Digital Imaging Bv Werkwijze voor het voor een waarnemer bepalen en weergeven van een kleurverschil tussen twee kleuren.
DE19506425B4 (de) * 1995-02-24 2004-11-18 Heidelberger Druckmaschinen Ag Offsetdruckverfahren
US5812705A (en) * 1995-02-28 1998-09-22 Goss Graphic Systems, Inc. Device for automatically aligning a production copy image with a reference copy image in a printing press control system
US5767980A (en) * 1995-06-20 1998-06-16 Goss Graphic Systems, Inc. Video based color sensing device for a printing press control system
US5805280A (en) * 1995-09-28 1998-09-08 Goss Graphic Systems, Inc. Control system for a printing press
US5903712A (en) * 1995-10-05 1999-05-11 Goss Graphic Systems, Inc. Ink separation device for printing press ink feed control
ES2129907T3 (es) * 1996-04-19 1999-06-16 Schablonentechnik Kufstein Ag Procedimiento de impresion a media tinta y maquina de imprimir para su realizacion.
EP0836941B1 (fr) * 1996-09-23 2001-06-27 Maschinenfabrik Wifag Groupe de champs de mesure et procédé pour la saisie des données de qualité dans les éditions (tirages) d'impression polychrome
US5809894A (en) * 1997-02-20 1998-09-22 Advanced Vision Technology, Ltd. System and method for registration control on-press during press set-up and printing
US5819655A (en) * 1997-08-20 1998-10-13 Bristol-Myers Squibb Company Cyclinder color printing method and product using improved misregistration detection
DE19749063A1 (de) * 1997-11-06 1999-05-12 Heidelberger Druckmasch Ag Verfahren zur Gewinnung von Farbmeßwerten
US5895836A (en) * 1997-11-06 1999-04-20 Uzik; Barry K. Greyscale calibration method in digital printing
US5974967A (en) * 1998-08-27 1999-11-02 Lenticulartechnologies, L.L.C. Registration system for lenticular printing
US6324975B1 (en) 1999-01-18 2001-12-04 Fuji Photo Film Co., Ltd. Color correcting method
DE69933244T2 (de) * 1999-07-12 2007-05-03 Sagawa Printing Co., Ltd., Muko Farbverbesserungsverfahren und vorrichtung sowie speichermedium worauf das farb-verbesserungsprogramm gespeichert ist
US7050196B1 (en) * 2000-06-20 2006-05-23 Eastman Kodak Company Color printer calibration
PL200158B1 (pl) 2000-12-06 2008-12-31 Avt Advanced Vision Technology Sposób sterowania kolorem na arkuszu drukarskim
US6564714B2 (en) * 2000-12-06 2003-05-20 Delaware Capital Formation, Inc. Spectral color control method
US6982812B2 (en) 2001-01-22 2006-01-03 Hewlett-Packard Development Company, L.P. Calibration of printing devices
CN1505564A (zh) * 2001-03-02 2004-06-16 ������������˹��˾Dba Mgi���� 印刷调节系统和方法
CN1537055A (zh) * 2001-07-30 2004-10-13 阿克利・马丁内斯公司Dba Mgi工作 色彩管理处理系统和方法
MXPA04000987A (es) 2001-07-30 2005-02-17 Ackley Martinez Company Dba Mg Sistema y metodo de un sistema de compensacion de mezclado.
US7032508B2 (en) * 2003-03-21 2006-04-25 Quad/Tech, Inc. Printing press
CN100458423C (zh) * 2003-03-21 2009-02-04 中国印钞造币总公司 彩色印刷质量检查方法
US7152941B2 (en) 2003-10-28 2006-12-26 Hewlett-Packard Development Company, L.P. Printing system calibration
US7411700B2 (en) * 2003-10-28 2008-08-12 Hewlett-Packard Development Company, L.P. Printing system calibration
US7605959B2 (en) 2005-01-05 2009-10-20 The Ackley Martinez Company System and method of color image transformation
JP5022682B2 (ja) * 2006-11-30 2012-09-12 リョービ株式会社 カラー印刷機の印刷画像品質管理方法及び印刷画像品質管理装置
JP2009178883A (ja) * 2008-01-30 2009-08-13 Ryobi Ltd カラー印刷機の印刷画像品質管理方法及び印刷画像品質管理装置
DE102010009226B4 (de) * 2009-03-13 2024-02-15 Heidelberger Druckmaschinen Ag Verfahren zur Steuerung des Farbauftrags in einer Druckmaschine
DE102009046853A1 (de) * 2009-11-19 2011-05-26 Manroland Ag Verfahren zur Bestimmung von Eigenschaften eines bedruckten Bedruckstoffs
DE102011012806B4 (de) 2010-03-24 2022-07-07 Heidelberger Druckmaschinen Ag Graubalancekorrektur eines Druckverfahrens
JP2017053805A (ja) * 2015-09-11 2017-03-16 セイコーエプソン株式会社 測色装置、及び印刷装置
CN110793976B (zh) * 2019-11-14 2022-04-12 苏州中科全象智能科技有限公司 一种印刷质量检测系统及方法

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0255924A2 (fr) * 1986-08-05 1988-02-17 FOGRA Deutsche Forschungsgesellschaft für Druck- und Reproduktionstechnik e.V. Procédé et dispositif pour influencer l'encrage d'une surface encrée dans une machine à imprimer

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3916168A (en) * 1973-10-09 1975-10-28 Mobil Oil Corp Color matching surface coatings containing metallic pigments
DD200665A1 (de) * 1981-07-28 1983-06-01 Wolfgang Arnold Verfahren zur einstellung der farbdosierung an druckmaschinen
DE3232577A1 (de) * 1981-09-12 1983-03-31 Dainippon Screen Manufacturing Co., Ltd., Kyoto Verfahren und vorrichtung zur farbkonzentrationsmessung in druckerzeugnissen
US4706206A (en) * 1983-09-20 1987-11-10 Kollmorgen Technologies Corporation Color printing control using halftone control areas
DE3539540A1 (de) * 1984-11-08 1986-05-22 Canon K.K., Tokio/Tokyo Farbbildbehandlungsverfahren
DE3687074D1 (de) * 1985-03-21 1992-12-17 Felix Brunner Verfahren, regelvorrichtung und hilfsmittel zur erzielung eines gleichfoermigen druckresultats an einer autotypisch arbeitenden mehrfarbenoffsetdruckmaschine.
US4967379A (en) * 1987-12-16 1990-10-30 Gretag Aktiengesellschaft Process for the ink control or regulation of a printing machine by comparing desired color to obtainable color data
DE58901780D1 (de) * 1988-01-14 1992-08-13 Gretag Ag Verfahren und vorrichtung zur farbregelung einer druckmaschine.
DE3913382C2 (de) * 1989-04-24 1995-12-14 Heidelberger Druckmasch Ag Verfahren zur Steuerung der Farbführung einer Druckmaschine

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0255924A2 (fr) * 1986-08-05 1988-02-17 FOGRA Deutsche Forschungsgesellschaft für Druck- und Reproduktionstechnik e.V. Procédé et dispositif pour influencer l'encrage d'une surface encrée dans une machine à imprimer

Also Published As

Publication number Publication date
EP0408507A1 (fr) 1991-01-16
JPH0356832A (ja) 1991-03-12
US5068810A (en) 1991-11-26
DE59003421D1 (de) 1993-12-16

Similar Documents

Publication Publication Date Title
EP0408507B1 (fr) Méthode de détermination des écarts de couleur entre deux surfaces tramées imprimées avec une machine d'impression ainsi que méthode de commande ou réglage de l'impression couleurs d'une machine à imprimer
EP0255586B1 (fr) Procédé et dispositif pour influencer l'encrage d'une surface encrée dans une machine à imprimer
EP0324718B1 (fr) Procédé et dispositif pour régler l'encre dans une machine à imprimer
EP0321402B1 (fr) Procédé de commande ou du réglage de l'encrage d'une presse à imprimer
EP2008818B1 (fr) Bandes de contrôle de pression améliorées destinées à la mesure de la couleur sur une matière d'impression
DE4431270C2 (de) Verfahren zur Steuerung der Farbführung einer autotypisch arbeitenden Druckmaschine
EP0914945B1 (fr) Procédé pour régler l'encrage dans une machine d'impression
DE10359322B4 (de) Verfahren und Vorrichtung zur Korrektur von nicht angepassten Druckdaten anhand eines farbmetrisch vermessenen Referenzbogens
EP0585740B1 (fr) Méthode pour la commande du processus d'impression dans une presse d'imprimerie à cliché trame en particulier une machine à imprimer offset à feuilles
DE19515499A1 (de) Verfahren zum Regeln der Farbgebung beim Drucken
DE102005060893B4 (de) Verfahren zur Ermittlung eines drucktechnischen Messwertes
DE4402828C2 (de) Messfeldgruppe und Verfahren zur Qualitätsdatenerfassung unter Verwendung der Messfeldgruppe
EP0505323B1 (fr) Procédé pour le réglage des grandeurs des points de trame pour une presse rotative à imprimer offset
EP0528094A1 (fr) Procédé pour obtenir les données relatives au pourcentage des points de trame
EP1291179B1 (fr) Agent d'essai et procédé pour contrôler l'impression offset et numerique
DE10150837B4 (de) Verfahren zur Bestimmung bzw. Umrechnung von Farbprofilen
EP0916491B1 (fr) Procédé pour déterminer des gradients colorimétriques
EP0920994A2 (fr) Procédé pour la détermination de valeurs de couleur
DE3942254C2 (fr)
DE102010009226A1 (de) Verfahren zur Steuerung des Farbauftrags in einer Druckmaschine
DE19830487A1 (de) Verfahren zur Ermittlung von Flächendeckungen in einem Druckbild
DE4402784C2 (de) Messfeldgruppe und Verfahren zur Qualitätsdatenerfassung unter Verwendung der Messfeldgruppe
DE4104537C2 (de) Verfahren zur Steuerung einer Farbführung einer Offset-Druckmaschine
EP1279502B1 (fr) Procédé de contrôle pour héliogravure
DE4242683A1 (de) Verfahren zum Steuern eines Farbauftrages in einer Druckeinheit

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19900709

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): CH DE FR GB IT LI

17Q First examination report despatched

Effective date: 19921102

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): CH DE FR GB IT LI

ET Fr: translation filed
REF Corresponds to:

Ref document number: 59003421

Country of ref document: DE

Date of ref document: 19931216

ITF It: translation for a ep patent filed

Owner name: SOCIETA' ITALIANA BREVETTI S.P.A.

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 19940217

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
ITTA It: last paid annual fee
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19990614

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19990616

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: CH

Payment date: 20000616

Year of fee payment: 11

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20000629

Year of fee payment: 11

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20000705

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20000705

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20010330

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20010731

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20010731

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20020501

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

Effective date: 20050705