JPH02143250A - Computer phototype-setting machine - Google Patents

Abstract

PURPOSE:To perform a color dot process by providing a means which decides the screen angle of a pattern matrix constituting a dot picture and the density of the dots by turning on the bit of the pattern matrix. CONSTITUTION:The screen angle theta of a pattern matrix is set by arranging the same numerals as numbers of dots constituting the pattern matrix on two sides of a right-angled triangle on both sides of the right angle so that they can maintain a fixed relation and, at the same time, the pattern matrix is set to the density corresponding to the number of dots by turning on several kinds of the same number, for example, 1 of dots. Then a block copy for a plate is produced based on the pattern matrix and dots of an arbitrary screen angle and density are printed by using the plate produced from the block copy. Therefore, dots of an arbitrary screen angle and density can be set easily and the color dot process can be processed with a computer.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a computerized phototypesetting machine capable of applying an angled mesh in consideration of color printing.

<Prior Art> Computerized phototypesetting machines, which process text information using a computer, are often used in plate-making work for text information.

Depending on the printed material, meshing may be applied for the purpose of emphasis, etc., and in this case, it is necessary to perform the meshing process to create a master plate for plate making.

When applying shading using only a black plate, the shading process has traditionally been performed using a computerized phototypesetting machine. In other words, a predetermined position is shaded based on layout information including the shaded position.

Here, unlike when meshing is performed using only a black plate, when meshing with colors is applied, there is a problem in that moiré fringes occur due to interference. The colored mesh is yellow (Y)
, magenta (M), cyan (C), and black (B) are superimposed and printed on a printing plate, but in order to prevent the occurrence of moire fringes, Y
, M, C, and B meshes must be printed with a predetermined relative angle difference.

Unlike the shading process for black plates, which requires only specifying the mesh position as described above, colored mesh requires selecting the mesh angle for each color, so it has not yet been processed in computerized phototypesetting. Ta.

For this reason, conventional color shading processing is based on 1.2 colors, printing methods, etc., and mesh angles such as Y, M, C, etc.
B mesh sheets were prepared in advance, and at the stage of creating the block, the worker selected the mesh sheet sets of Y, M, and C1B as appropriate and pasted them onto the block mount.

A computerized phototypesetting machine of the present invention that achieves the above object is a computerized phototypesetting machine that forms a mesh image having an arbitrary screen angle and density, and includes means for determining the screen angle of a pattern matrix constituting the mesh image. , means for determining mesh density by turning on bits of a pattern matrix.

<Problems to be Solved by the Invention> Since the conventional colored hatching process was performed manually, there was a possibility that an error would occur in the selection of the mesh angle. There has also been a demand for expanding the range of computer phototypesetting by computerizing the color shading process, thereby further improving the efficiency of plate-making work.

The present invention has been made in view of the above-mentioned conventional circumstances, and an object of the present invention is to provide a computerized typesetting gate capable of carrying out color shading processing.

<Means for Solving the Problems><Operation> The computer phototypesetting machine of the present invention divides the dots constituting the pattern matrix into two dots with the same number sandwiching a right angle of a right triangle.
In addition to setting the screen angle of the pattern matrix by arranging it so that a constant relationship is maintained in the length of the sides,
Several types of dots with the same number are turned on, and the pattern matrix is set to a density corresponding to the number of dots turned on. Then, a master plate for plate making is produced based on this pattern matrix, and a mesh having an arbitrary screen angle and density is printed using a plate produced from this master block.

<Example> The computerized phototypesetting machine of the present invention will be specifically described based on an example.

As shown in Figure 2, the general configuration of the computerized photocopy machine is as follows:
Keyboard 1, storage device 2 using magnetic tape, computer v
II4 and a printing device 6.

The functionally divided structure of the computerized phototypesetting machine is shown in FIG. That is, the computer phototypesetting machine includes a character information input section 10, a character information storage section 12, a layout information input section 14, a layout information storage section 16, a pattern matrix creation section 18, a pattern matrix storage section 20, a layout editing section 22, and a storage section. 24, and an output section 26.

The character information input section 10 is a part for manually inputting character information to be printed, and this character information includes character data representing a character and position data specifying a print position of the character. This character information input section 12 is constituted by a magnetic tape device 2, and character information stored in advance on a magnetic tape is manually inputted to the computer 4.

The layout information input section 14 inputs print data that specifies the printing method of the printed material, format data that specifies the format such as the paper size of the printed material, printing line spacing, and margins, color data that specifies the color of the color mesh, and designation of the printing position of the mesh. This is the part for inputting layout information including position data. The layout information input unit 4 is constituted by a keyboard 1, and by operating the keyboard 1, layout information is input into the computer 4.

The pattern matrix creation section 18 is a part that creates a pattern matrix that defines angles and densities as described later, and when creating a new pattern matrix according to the conditions at the time in addition to the preset pattern matrix. used for. This pattern matrix creation section 18 is constituted by a keyboard 1, and by operating the keyboard 1, pattern matrix information is manually inputted to the computer 8!4.

The character information storage unit 12 is a part that stores character information input from the character information human power unit 10.

The layout information storage section 16 is a section that stores layout information input from the layout information input section 14.

The pattern matrix storage unit 20 is a part that stores pattern matrices of screen angles for each of yellow (Y), magenta (M), cyan (C), and black (B) constituting a color mesh, and is used for offset printing,
Depending on the printing method such as gravure printing, Y, M,
In addition to a plurality of sets of pattern matrices in which pattern matrices for each of C and B are set as one set, a pattern matrix set newly created by the pattern matrix creation section 18 is also stored.

The layout editing section 22 reads character information from the character information storage section 12 and layout information from the layout information storage section 16, links the layout information to the character information, and also reads out the corresponding pattern matrix from the pattern matrix storage section 20 based on the layout information. This is the part that reads out information and connects this information to text information.

The storage unit 24 is a part that stores information in which character information is associated with layout information and pattern matrix information in the layout editing unit 22.

The character information storage section 12, layout information storage section 16, pattern matrix storage section 20, and storage section 24 are the electric W-machine 14.
The layout editing section 22 is composed of a computer 8i1 memory.
It is composed of four arithmetic units.

The output unit 26 is a part that prints on an output medium (photographic paper, film, etc.) for the printing plate based on the information read from the storage unit 24 and discharges the printing plate for plate making. This output section 2G
is constituted by a printing device 6.

Color shading processing by the computerized phototypesetting machine having the above configuration will be explained.

First, character information is input manually from the magnetic recording device 2 to the computer 4, while layout information is input to the computer 4 from the keyboard. These pieces of information are stored in the memory of the computer 4, and are subjected to arithmetic processing by an arithmetic unit to link the character information with layout information such as a predetermined format. In this calculation process, the printing method is specified by the print data included in the layout information, the printing position of the mesh is specified by the position data, and the color of the mesh is specified by the color data. Pattern matrix information that specifies the screen angle corresponding to the printing method for each of the color elements Y, M, C, and B of the color specified based on the data is read and linked to the character information. And allocation information,
The character information associated with the pattern matrix information is input to the printing device 6, and characters are printed on the printing output medium at a predetermined position in a predetermined format based on M4 multiplication processing for each color element, Printing output media for each color element with relative angles set in the mesh are discharged from the printing device 6.

Next, the concept of the pattern matrix that defines the screen angle and density for each color element of the hatching process will be explained.

Pattern matrix information includes each color element Y, M, C, B
As shown in Figures 3 and 4, respectively, the positional relationship of the same numbers is a halftone dot pattern that has a constant screen angle by keeping the relationship of the lengths of the two sides that sandwich the right angle of the right triangle constant. A halftone dot pattern consisting of a matrix, in which several types of dots with the same number are turned on, and the density corresponds to the number of dots turned on (a collection of elements 1 to 10 as shown surrounded by thick lines in Figure 3) This halftone dot pattern is printed as one mesh when printing.

In other words, in color yi multiplication, each color element Y, M,
A color WI pattern is obtained by turning on several types of dots with the same number in the C and BW pattern matrices so as to achieve a desired density and performing heavy printing.

In the same figure, the relationship between "1" and "1" in the pattern matrix is assumed to be 3:1 in terms of the lengths of the two sides (number of dots) that sandwich the right angle of a right triangle, and the screen angle θ (tan θ =3) is attached. Then, by arranging right triangles with a ratio of 3:1 as shown in Figure 5, the area of one halftone dot (the smallest unit constituting the pattern matrix) during printing (dot r1
1) can be obtained. In this example,
(3+1)'2-(3*1zero2)=10 dots.

In other words, if we generalize the lengths of the two sides of a right triangle as a and b, the area of one halftone dot (the minimum unit that makes up the pattern matrix) is a''''2 + b'''2,
By changing a and b, the screen angle θ can be changed. In addition, in FIG. 6, the relationship between "1" and "1" in the pattern matrix is assumed to be 3:3 with the length of the two sides (number of dots) that sandwich the right angle of a right triangle.
The screen angle θ (tanθ=
An example with 1) is shown below.

Here, the pattern matrix must be arranged so that no matter how it is arranged vertically or horizontally, there will be no deviation in positional relationship, so as shown in Figure 7, the distance until the same pattern appears in the X-axis direction and the Y-axis direction is This is the length of one side of the pattern matrix.

Assume that one halftone dot as the minimum unit constituting the pattern matrix is located at the shaded position in Fig. 7, and the point P
is at the origin of the XY coordinates, the coordinates of the end position aPx on the X axis and the end position py on the Y axis of the pattern matrix cannot be expressed as follows, and the point Px has a slope b'/a'
(Since the slope is divided by the greatest common divisor of a and b, aI
b l are relatively prime), and the straight line Y=-('a
'/b' ) A straight line Y - (-na) = (b'/a' ) (x
-n-b)... (1) However, n
is the coordinate value when Y=O in the integer>.

Solving the above equation (1), Y=O and X=n・ (a-a
'+b-b')/b'. Here, since X is an integer value, n=b'. Therefore, X=a'a'
+b 'b', so Px= (a・a'+b
-b' O).

Also, the point py has a slope of −a l / b l and is (a,
Straight line passing through the coordinate values with b) as the unit of movement Y-n-b=-(a'/b') <x-n-a
)...(2) (where n is an integer), the coordinate value is when X=00.

Solving the above equation (2), X=0 and Y=n・ (a-a
'+bb')/b'. Here, since Y is an integer value, n=b'. Therefore, Y=a-a'
+b −t)′, so Py=(0,a−a′
+bb').

As mentioned above, from the results of Px and Py, the pattern matrix is always square.

According to the above rules, a pattern matrix with a screen angle θ is created for each color element of Y, M, C, and B, and a screen angle θ that prevents the occurrence of moiré fringes is assigned to each gold element. Each pattern matrix is considered as one set as pattern matrix information.

For example, for offset printing, the angle θ is Y=Do'
M: 75" C: 15'B45', and for gravure printing, the angle θ is Y: 60°, M:
75” C: 15” B45°. In addition, in offset printing, the relative angle difference other than Y is 30
If the angle is 90°, there will be virtually no moiré problem, so for example, Y: 90° Mnear 0" C: 10' B:
Settings such as 40' are also possible.

In the computerized phototypesetting machine of this embodiment, the pattern matrix as described above is formed in accordance with the procedure shown in the flowchart of FIG. 8, and is imported into the computer 8!4 as a bitmap. Note that in the following example, n=3 and b=i.

First, a screen angle θ is determined on the computer 4.
In order to correct the shape of halftone dots and dots, the following adjustment table is imported (step Sl).

<Adjust table> Next, from a and b, the area (number of dots) of the minimum unit constituting the pattern matrix is calculated as n=a・alb−
b (step S2).

In this example, n=3.3+1.1=10.

Next, the length h of one side of the pattern matrix is h=
It is calculated from n/c (where C is the greatest common divisor of a and b) (step S3). In this example, h=10/
1=10, and each side of the pattern matrix has 10 dots.

Next, as shown in FIG. 9, the dots are numbered such that the upper left corner of the pattern matrix is numbered "1" and numbers up to rnJ appear in row C (step S4).

Next, as shown in FIG. 0, a position moved downward by a(3) dots and b(1) dots to the right from the upper left corner of the pattern matrix is set as the next "1" and the process of step S4 is repeated. Note that when numbering dots, those that exceed the range of the matrix are moved to the remainder position divided by h (step S5). In this way, the entire range of the matrix is numbered from "1" to rnJ (riot) to create a pattern matrix as shown in FIG. 11 (step S6).

Next, the numbers assigned to the pattern matrix are converted according to the above adjustment table, and the arrangement form of the numbers assigned to the pattern matrix is changed as shown in FIG. 12 (step S7), that is, in the state shown in FIG. 11. Even if you increase the number to turn on one dot at a time, it will only be linear, so "1" to "n" near "1"
(``10'') are regarded as one group and the numbers are converted. By converting the numbers in this way, in the minimum unit of the pattern matrix consisting of numbers "1" to "rn" (riot), when increasing the number to turn on one dot at a time, it becomes close to a circular shape. , can form a mesh.

The screen angle θ of the pattern matrix is set by the series of processes described above, and by arbitrarily selecting the values of a and b, the screen angle θ of the pattern matrix can be arbitrarily set.

Next, “1” to “n” (“10
”), and is stored in the memory of the computer 4 as pattern matrix information in which the density becomes darker by increasing the number of bits turned on (step S8).
．． 9). That is, the density of the minimum unit consisting of a set of "1" to rnJ (rlOJ) is defined by the number of bits turned on, and accordingly, the density of the mesh to be printed is also arbitrarily defined by this. In this example, by turning on bitmaps from "1" to rlOJ in order, you can obtain 10 types of density-based bitmaps. For example, "1"
” to “4” are turned on and the others are turned off, the state shown in FIG. 13 is obtained.

Furthermore, since the present invention can easily obtain a mesh pattern with arbitrary screen angle and density, it is particularly effective when used in color mesh processing, but it can of course be used not only in this but also in black plate printing. can. Further, in the above embodiment, the case where characters are shaded is explained, but the present invention is not limited to this, but can also be used for processing in which a certain range is shaded.

<Effects> According to the computerized phototypesetting machine of the present invention, it is possible to easily obtain meshes with arbitrary screen angles and density, and it is possible to realize computerized color shading processing. Even if there is, the block copy can be produced using consistent computer typesetting.

Therefore, it is possible to eliminate errors caused by the acquisition process, and to achieve thorough computer processing, which greatly improves production efficiency.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the functional configuration of the computerized phototypesetting machine, FIG. 2 is a configuration diagram showing the computerized phototypesetting machine according to an embodiment of the present invention, and FIG. 3 is a diagram showing an example of a pattern matrix. Figures 4 and 5 are diagrams each explaining the creation of a pattern matrix, Figure 6 is a diagram showing another example of the pattern matrix, Figure 7 is a diagram explaining the size of the pattern matrix, and Figure 8 is a diagram explaining the creation of the pattern matrix. Flowcharts illustrating the computer processing of the pattern matrix, and FIGS. 9 to 13 are diagrams each explaining the concept of the computer processing of the pattern matrix. 1 is a keyboard, 2 is a magnetic storage device, 4 is a computer, 6 is a printing device, 10 is a character information input section, 14 is a layout information input section, and 22 is a layout editing section. Patent applicant Toppan Printing Co., Ltd. Agent
Patent Attorney Kiyoshi Kuwai - Figure 2, Figure 1, Figure 3, Figure 4, Figure 6, Figure 7, Figure 9, Figure 11, Figure 12, Figure 13

Claims (1)

[Claims] A computerized phototypesetting machine for forming a mesh image having an arbitrary screen angle and density, the computer photosetting machine comprising means for determining the screen angle of a pattern matrix constituting the mesh image;
A computerized phototypesetting machine comprising: means for determining mesh density by turning on bits of a pattern matrix.