JPS5822178Y2 - contact screen - Google Patents

Description

[Detailed description of the invention] The present invention is an electronic color separation scanning device that scans a color original image and simultaneously reproduces and records a plurality of color separation plates. Regarding contact screens.

In multicolor printing, printing plates are created that separate the original color image into four colors, for example, yellow, magenta, cyan, and black, and these printing plates are printed over and over again to reproduce the tones of the original image. In recent years, electronic color separation devices called color scanners have been put into practical use.

When performing color separation using such a color separation device, if the device is equipped with an image reproducing and recording device and only one unit, it is possible to reproduce and record only one color in one scan, and it is possible to reproduce and record only one color in one scan. In order to obtain a color separation plate, one color original image needs to be scanned four times, which is time-consuming and requires a lot of effort such as loading and unloading the recording film and setting up the device for each scan. There are drawbacks that require

Furthermore, when a plurality of image reproduction/recording apparatuses are operated in parallel, the apparatus becomes large-sized and the equipment costs are high.

Furthermore, in the case of a rotating cylinder, which is most commonly used in such electronic color separation scanning devices, even if the size of the color original image 3 is smaller than the circumference of the cylinder 1, as shown in FIG. Since it is normal to wrap it around the entire circumference of 2 and attach it, only a part 5 of it is used, which is inefficient.

Therefore, it is possible to combine multiple color original images and perform color separation at the same time, but in order to obtain good color separation results, it is best to select color original images that have almost the same color density and other conditions. It is not practical because the combinations are limited.

A more efficient electronic color separation scanning device that overcomes the above-mentioned drawbacks may be the one shown in FIG. 2.

That is, in the case shown in FIG. 2, a color original image 3 attached to a part of an original image cylinder 1 is scanned, and a yellow separation plate 6Y, a magenta separation plate 6M, a cyan separation plate, for example, are printed on a recording film 4 mounted on the recording cylinder 2. This is an electronic color separation scanning device that simultaneously reproduces and records a separation plate 6C and a black separation plate 6K in one scan, and stores a plurality of color separation signals obtained by scanning a color original image once in a memory device. During one rotation of the writing and recording cylinder, a single recording head is controlled by sequential reading, and color separation plates are created.

As described above, the present invention is an electronic color separation system in which a plurality of color separation plates are simultaneously reproduced and recorded in the direction of the length of the storage film on the recording cylinder while scanning the original color image on the original cylinder once. Applies to scanning devices,
Furthermore, the present invention relates to a contact screen which is mounted directly on the recording film of the recording cylinder in this type of electronic color separation scanning device to perform color separation and obtain a shaded color separation plate at the same time.

FIG. 3 shows an embodiment of the contact screen of the present invention.

In this embodiment, on one rectangular film 7A, the screen angle with respect to one appropriate side is Oo, 7
Four screen surfaces 7Y forming 5°, 15°, and 45°,
7M, 7C, and 7K are arranged adjacent to each other, and each screen surface 7Y, 7M, 7C, and 7K is shaded and color-separated on the recording film 4 to form a yellow separation plate 6Y, a magenta separation plate 6M, and a cyan separation plate 6C. , black disassembly version 6
In order to correspond to K, the contact screen 7 is formed by continuous formation.

As shown in FIG. 4, a contact screen 7 is attached to each color separation plate 6Y, 6M, 6C mounted on the recording cylinder 2 in the apparatus shown in FIG.

The screen surfaces 7Y, 7M, 7C, and 7K are wrapped around the recording cylinder 2 so as to be in close contact with the 6K, and by scanning and exposing the recording cylinder 2 with a scanning beam from above, a shaded color separation plate can be obtained. .

Note that in this embodiment, the contact screen 7
is for 4-color separation, but if the number of separations is 2 colors,
In the case of three colors or five or more colors, the required number of screen surfaces having screen angles corresponding to the desired colors are placed adjacent to each other on one film in correspondence with the position on the recording film to be played. By forming such a structure, it can be used for two-color separation, three-color separation, or separation of five or more colors.

Since the contact screen of the present invention has the above-described structure, it is easy to attach, remove, and position the contact screen to the recording cylinder, and it is convenient to handle.

In addition, the contact screen of the present invention does not cause the screen surfaces to shift relative to each other during use, so
As long as the screen angle and halftone dot arrangement of each screen surface are precisely set during manufacturing, the positional relationship between them can be maintained accurately at all times, resulting in highly accurate halftone color without misalignment. You can get a disassembled version.

Therefore, if the halftone dot arrangement on each screen surface is manufactured in advance in an ideal arrangement, it is possible to reliably prevent moiré from occurring on prints produced by color separation plates obtained using the contact screen. can.

Furthermore, in the contact screen of the present invention, since each screen surface can be integrally formed on one film, the halftone dot characteristics of each screen surface can be made uniform with high precision, and accordingly, As a result, it is possible to homogenize the mesh image of each color separation plate obtained as a result, and there are advantages such as being able to obtain a high-quality color plate that cannot be obtained by conventional meshing.

[Brief explanation of drawings]

Figure 1 is a diagram showing the state of electronic color separation recording using the conventional one-cylinder system, and Figure 2 is a diagram showing electronic color separation recording, which allows multiple color separation plates to be obtained simultaneously from a single color original image. Figure 3 is a diagram showing the recording status of the resolution scanning device.
In the contact screen according to the present invention, diagonal lines simply indicate the arrangement of halftone dots. FIG. 4 shows the contact screen according to the present invention in a second
This is applied to the electronic color resolution scanning device shown in the figure. 1... Original picture cylinder, 2... Recording cylinder 3... Color original picture, 4... Recording film, 5.6 Y, 6M, 6 C, 6K・・・・・・
・・Color separation version, 7・・・・Contact Sphunone,
7A...Film, 7Y, 7M, 7C, 7K.
...Screen surface.

Claims (1)

[Scope of utility model registration request] In an electronic color separation scanning device that simultaneously reproduces and records a plurality of color separation plates on a recording film of a recording cylinder while scanning a color original image of an original image cylinder once, In order to obtain two or more screen surfaces having different screen angles corresponding to the color separations, two or more screen surfaces having different screen angles corresponding to the color separations are consecutively placed adjacent to each other on a single film so as to match the playback recording position of the corresponding color separations. A contact screen for color separation halftone shading in an electronic color separation scanning device.