JPS60112042A - Color simulation method - Google Patents

Abstract

PURPOSE:To know a color to be printed and a plate density value for printing a preferable color from a plate density value by simulating a color expressed by dot percent, etc., as the color of actual printed matter speedily. CONSTITUTION:When a color is simulated from the value of plate density, a printing system is selected with a switch 61 and knobs 12Y-12K for color quantity adjustment are rotated over a look at display devices 83Y-83K of respective colors until the display values are specified values. Consequently, the color printed with the set plate density is displayed on the display screen 55 of a monitor device 50. When the plate density value for the preferable color is obtained from the preferable color, a system is selected by a system selecting means 60 and then the knobs 12Y-12K for color quantity setting are rotated over a look at the display screen 55 of the color monitor 50 to project the preferable color on the display screen 55. Consequently, the color to be printed with the plate density is known from the plate density value and the plate density value for printing the preferable color is also known from the preferable color.

Description

DETAILED DESCRIPTION OF THE INVENTION In printing, various colors are expressed by using multiple colors of ink and overprinting the paper by changing the amount of color (the amount of ink per unit area) on the printing paper. The amount of each color ink to be printed on printing paper differs depending on the printing method.For example, in offset printing, it is expressed in %, which is the area ratio of halftone dots on a separation plate. is normal,
In gravure printing, it is common to express the density of transmission on a separation plate. Hereinafter, in this specification, the expression of color amount generally employed in various printing methods will be referred to as plate density.

By the way, when receiving an order for printing, colors may be specified (for example, yellow; Y, etc.).

Magenta; M number of lines, cyan: C number of lines, Black; number of φ
It is designated by Tonotochi, such as. Each color is like this)
When a color is specified by plate density such as %, there is no device that can easily show what color that color actually is. or,
On the other hand, if a desired color is created by appropriately adjusting the color amount of each ink color, there is a device that can easily determine, for example, how many dots percent the plate density of each color should be in order to print the created color. There was no.

This invention was made in view of the above circumstances, and when the color amount of each ink is specified by the density of the same plate, the actual color can be determined electro-optically. This invention relates to a method for simulating a color, and on the other hand, it is possible to know the dot % equal plate density when printing a desired color based on a preferred color.

The present invention will be explained in detail below using one example.

In this embodiment, channel 1 is for offset and is expressed as dot % as plate once, and channel 2 is for gravure and is expressed as plate density as transmitted density of the separated plate. This is what has been set.

As shown in Figs. 1 and 2, the color amount setting means [0] is used to set the color amount of each color of ink used in printing to an arbitrary value from 0 to so-called peta, and the number of inks used is It has a lust setting device. That is, since the inks generally used for color printing are basically four colors of Y-M and C-K, in this embodiment, four color amount setters (11Y) (11M) for Y-M, C, and ) ('11c) (11K)'. This color amount setting device is a variable resistor, and its input terminal is connected to a constant voltage power supply, and each color amount knob (12Y) (12M) (12C) (12K) of the variable resistor is connected (see Figure 2). By rotating and adjusting, it is possible to set the desired lust. In this case, the color amount is the color amount on the printing paper,
The color amount O (zero) is set to 0.7 V, the solid color amount is set to 0■, and any value between them can be set.

In this way, each lust setting device (11Y) (11M) (
11C) (11K) to the color amount signal (16Y) (16M) (16C) (16K) corresponding to the color amount of each color on the printing paper.
) is output. This color signal (16Y) (16M) (
16C) (16K) is the matrix means (21N (2I
I and the color amount-to-density conversion means σ@.

Matrix means (2) calculates the color amount of each ink on the printing paper as described above, and calculates the color amount of TV staff red; R, green; G, full; B (color C) when viewed from the printing paper.
intensity of each fluorescent color on RT),
As shown in the figure, it is equipped with an overlay correction means □□□ and an ink color-TV color conversion means (401). The color amount of the ink that has been printed does not appear additively, but appears as a slightly decreased color amount, and especially in areas where there is a large amount of overprinting, the color amount appears as a large decrease. be.

Regarding such amendments, the
48921, Japanese Patent Publication No. 54-58922, etc., detailed explanation will be omitted. The overlay correction means (up to) of this embodiment is
The circuit described in Publication No. 38922 is adopted.

Also, in't-color-TV color conversion means +4tH'! ,
This is a means of converting the ink colors Y, M, (, K) into the six primary colors of television, R, G, and B, and this conversion means is U+S+PA5131252+U-S.

PA51236 (S6, U, S, PA312833
! Since it is disclosed in Japanese Patent Application Laid-Open No. 49-40819, etc., a detailed explanation will be omitted.

It should be noted that the ink overlay correction means (Inc.) and the ink color-TV color conversion means (4.
A calculation circuit that simultaneously performs two types of calculations may be used, as shown in Japanese Patent Application Laid-open No. 027 and JP-A-56-167028.

Here, in such matrix means.

If the printing method is different, the overlay correction means C3
If the correction coefficient of 0) is different, and the ink color is different, the color amount conversion coefficient of the ink color-TV color conversion means (4) is different. Therefore, in this embodiment, two It has a matrix means c!UI C1!II, which can be changed by a changeover switch t61) by a method selection means. The matrix means (211) has the same circuit groove configuration as the matrix means (20+), and the correction coefficients of each means (a) (201') are adjusted to different values.

In this way matrix means (201 or (211
The six primary color signals (51R) of the color television system obtained from (
51G) (51B) is input to a color monitor device φ0) having a color CRT;
The display screen e551 of o) has three primary color signals (51R) (51
C)) The color is displayed based on (51B).

In this way, the print color of the color amount set by the color amount setting means αα in the printing method selected by the method selection means (6) is displayed on the color monitor device.

Color amount setting means (color amount signal (1
6Y) (16M) (16C) (16K) is input to the color amount-density conversion means ff0), and is the plate density (value) of each plate adopted in the printing method simulated in the conversion means (10). is converted to

In other words, if it is an offset printing method, as mentioned above (the dots, which are the halftone dot percentages on the separation plate, are used as the plate density, the color tone signals of each color (16Y) (16M) (1
6C) (16K) is an analog-to-digital converter (71Y) (71M) (71C') (71K) for each hue to generate a digital signal (for example, a digital value of 0 to o7v*o to ioo)
After being converted to L, it is input to the color amount-density converter Q and converted to the corresponding dobutochi value.
It is output as an i signal (76Y) (76M) (76C) (76K).

A color amount-to-density conversion means (a typical converter) consists of a so-called microcomputer.
Various conversion formulas are stored in advance for each method,
Based on the printing method selected by the method selection means (60), a method selection signal (62
Each separate conversion formula is adopted to convert the color amount signals (16Y) (16M) (16C) (16K) into density signals (76Y) (76M) (representing the plate density of the corresponding system).
76C) (76K).

An example of a conversion formula for such calculation is shown in FIG. The figure shows a conversion formula for converting the color amount signal for Y into a dot% in the offset printing method. Correspondingly, zero input signal corresponds to the required solid density.

In this embodiment, there are two methods (two channels) that can be selected by the method selection means, and different matrix means and conversion formulas are adopted for each channel. is set for offset, and channel 2 is set for gravure, but both channels may be used for offset or gravure, and the number of channels may be increased as necessary. For example, even with the same offset printing, the reflectance of the ink differs depending on the printing paper used, and if paper with poor reflectance (high-quality paper, newsprint, etc.) is used to print the same amount of color, there will be a larger drop. )
In this case, the method selection means (CA) can increase the number of channels that can be selected, and even if the same matrix (■) is used, the color amount-density conversion means + 71 can use different conversions. It's okay to make it possible to choose the formula.

Fig. 4 shows a flowchart of the color quantity-density converter (716). Here, 0A-2 (716), CAL-4 (746
).

CAL-6 (756) - CAL-8 (766) are each color amount of Y, M-C, for channel 1 (0 = color amount of peta).

This is a calculation step for calculating the plate density of the negative edge for offset from 1oo - color amount zero). Also CA
L 1 (715), CAL-3 (745), CAL-
5 (755), CAL-7 (765) is a gravure negative gutter from the color amount of Y, M, C, for channel 2)
This is a calculation step to add %. Also, CAL-10 (7
25) is a calculation step for converting a negative dot s into a positive dot. Further, CAL-9 (725) is a calculation step for calculating the negative transmission density from the negative dot %. CAL-11 (727) is a calculation step for calculating the positive transmission density from the negative transmission density. In each calculation step, a conversion formula is stored in advance, and the conversion calculation is performed based on this stored conversion formula.

First, start the program with Start (701).

Check whether the channel selected by the method selection means is channel 1 or 2 in the initial cell (702), check whether the plate density is expressed in each channel (dob)% or density, and press the negative/positive switch (702). Check whether it is negative or positive, and perform initial setting such as clearing each memory.

Next, input the values of Y, M, C, with YM, CK large input 705), and the value of Y input with the next y,, = y' (71o) is stored in the memory y/. Judge whether it matches the value or not, and if it matches and takes 1 step, '(Memory Y' is O~1
Since it is initialized to a value other than 00, the memory y is small (does not match at first) Y'←y (711)
The value entered in / is memorized, and the arrow B←Y (71
In 2), let the value of memory B be y.

Next, it is determined whether the channel selected by CH-1 (714) is 1, and if it is channel 1, CAL-2
(716), the conversion operation shown in FIG.
-DOT%(7
20), it is determined whether the plate density is expressed in %), and if it is %), the next negative (722) is used to determine the negative/positive switch haze, and in the case of negative, A← calculation result (7).
In step 28), the calculation result of Y is stored in memory A. The value of memo 1J-B is determined by the next B-'i' (729), and if memory B is y (the previous one is self-B4-y (712
) and memory B is y. ) next y′←A (
750), the calculation result stored in the memo IJ-A is stored in the memory y', and the primary KM=M' (740)
Proceed to.

+ CAL-10 (72) for negative (722) and positive
In step 3), the value is further converted from the dot percentage of I/G to the dot percentage of positive, and then the process proceeds to A (- calculation result (72B)).

In addition, if channel 2 is selected here, CH
-1 (714) goes to CAL-1 (715), conversion calculation for 2 channels is performed, and the first dot% (720)
Proceeds to CAL-9 (725), where a calculation is performed for the value of Y to convert from negative dot % to negative transmission once, and in the first negative (726), the negative/positive of the negative/positive switch haze is determined, and in the case of negative is just A ← calculation result (728)
If the value is positive, a negative→positive conversion operation is performed on the value in CAL-11 (727), and then the process proceeds to A←calculation result (72B).

M = M' (740) is input, the value of f, -M and memo IJ
−M′, and since they do not match at first, the next M
′←Proceed to (741).

Following steps similar to those for Y, m'←A(731
) and proceed to CC' (750).

Furthermore, the same applies to (.

In this way the memory yJ, m/, c'-k'KY
- After the calculation results of each plate density for M, C, and M are stored.

Proceed to output y'm'C' (770), and in this step (770) output the calculation results of the plate strength of each color to the output display means (0), and then set change ( 771
) to determine whether there is a change in the initial set data.

If there is no set change, proceed to YMCK input (703) and input the value of y-M-s-K.

Then, the newly input Y value in the next y-Y' (710) is compared with the previous YYO value stored in the memo IJ-Y', and if they are the same, the set is changed (713). ,xA
= ta' (74o), and if different, repeat the step of adjusting the Y plate density as described above, and then M = M' (
740).

If there is a set change, the process advances from the set change (771) to initial cellar 1- (702), and further to YMCK manual power (705) and Y=Y' (710).

Here, if Y=Y', cent change (715), B←y
(712), and in the case of Y\t', Y'←Y(711
), the program advances to B4-Y (712), and in any case enters a routine in which the plate density of Y is calculated. Similarly, when there is a set change, the plate density of M, (, is also calculated again.

Digital density signals (76Y) (76M) (76C) (76K) are converted into signals corresponding to plate density according to each method by the color amount-density conversion means (70) and output as described above.
) is a display means H1 consisting of an LED digital display device.
(Q) and is input to the display device (85Y) (85M) (of each ink color via the display device drive circuit (8η).
85C) (83K) and the corresponding numerical value is displayed.

In this way, the plate density value of each color, such as the percentage of each color amount set by the color amount setting means uO) in the printing method selected by the method selection means 60), is displayed on the display means 180). be done.

When using the apparatus according to the present invention, the correction coefficients of the matrix L2Q1 F2+1 and the color amount-density conversion means are set according to the printing method corresponding to each channel selected in advance by the method selection means. Set the conversion formula (70) (.

When simulating a color based on the value of the degree of manufacture of one board, first select the printing method using the switch of the method selection means, and select the display device (85Y) (83M) for each color.
(83C) While looking at (83K), turn the color adjustment knob (1)
2Y) (12M) (12C) (12K) and set the displayed value to the specified value.

As a result, the display surface (55) of the cuff monitor device 0) displays the color that would appear when printed with the set board quality.

In addition, when obtaining a board production direct from a preferred color for printing that color, first select the method using the method selection means ((), then set the color amount while looking at the display screen 6119 on the color monitor device side. Knobs for (12Y) (12M) (12C)
(12K) to project a preferred color on the display surface t55). Then, when a desirable color is found, the printability value when expressing that color by printing is determined by each color's display device (83
Y) (83M) (85C) (83K) K is displayed.

Since the present invention has the above configuration, it has excellent practical effects as shown below.

That is, in the past, when a color was specified by a board quality such as 0.5%, there was no suitable device that could show what color that color would be in actual printing. However, according to the present invention, it is possible to quickly (simulate) the color expressed in %, etc., as the color of an actual printed matter, and at almost no cost.

On the other hand, when a desirable color is created by suitably adjusting each color of Y, M, C, etc., it is possible to quickly and economically determine the degree of board production such as the percentage of each color when the desirable color is obtained by printing. You can know.

As described above, according to the method of the present invention, it is possible to know the color to be printed with the degree of board production directly from the production of the board, and also to know the direct production of the board to print that color from the preferred color. It has practical effects.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which Fig. 1 is a block diagram of the color simulation device, Fig. 2 is a perspective view of the color simulation device, and Fig. 3 is a conversion formula of the color amount-once converter. A graph diagram showing an example of, Fig. 4 is a color amount -
3 is a flowchart of a concentration converter. αB...Color number setting means (11Y) (11M) (11C) (11K)...Color amount setting device (12Y) (12M) (12C (12K)
...Knob (16Y) (16M) (1 (SC) (16
K) ...Color amount signal (20I (2υ) ... Matrix means (30) ... Overlay correction means (4 (power ... Ink color - blur color conversion means (50)
...Color monitor device (51R) (51G) (51B)...Three primary color signals of television system 65)...Display surface (60)...Method selection means 1811...Selector switch +h2)... Method selection signal (6)...Negative/Positive switch (70)...Iron-density conversion means (71Y) (71M) (71C) (71K)...A
/D converter q□□□...Color amount-density converter (76Y) (76M) (76C) (76K)...
・Concentration signal tSO)...Display means t81)...Drive circuit (a 3Y) (83M) (83C) (83K)
...Display device patent applicant Toppan Printing Co., Ltd. Representative Kazuo Suzuki

Claims (1)

[Claims] 1) Adjustably set the color amount of multiple inks to obtain the corresponding color signal, perform trapping correction on the obtained color signal, and convert the ink color to TV color. The color is displayed on a color TV using the three primary color signals, and on the other hand, the color amount signal is converted to a corresponding plate density according to the printing method to be simulated, and the result of this calculation is sent to the display device. A color simulation method characterized by displaying a printing color for an arbitrary color amount and a corresponding plate density value.