JPH0679864A - Miss-register monitor - Google Patents

Abstract

PURPOSE:To monitor the displacement of a register mark on a display screen. CONSTITUTION:A scale 3 is mounted at a position, where a register mark 2 passes, and the scale 3 and the register mark are irradiated with a flashing light source 6 while the scale 3 and the register mark 2 are image-sensed by a TV camera 7. A timing generating circuit 8 generates a timing signal when the register mark 2 reaches the position of the scale 3, and the flashing light source 6 and the TV camera 7 are operated by the timing signal. Image-sensing data are taken into an image memory 9 on the basis of the timing signal, and displayed on a display unit 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a misregistration monitoring device for monitoring a predetermined part of a picture.

[0002]

2. Description of the Related Art As a method for inspecting an object that moves at high speed, the object is irradiated with an instantaneous flash illumination such as a stroboscope, and an instantaneous image obtained by the irradiation is accumulated on an image pickup surface of an image pickup device and one scan thereof is performed. A method is adopted in which, after storing minute video signals in a storage device, the images of the object are monitored as a still image by sequentially displaying the video signals on a display device such as a television monitor while reading the video signals from the storage device. Such techniques are disclosed in Japanese Patent Laid-Open Nos. 54-138954 and 56-51181.

Further, automatic register control for optically correcting register marks (register marks) of each color printed on the printing surface, calculating the amount of register deviation, controlling a correction roll, and automatically correcting register deviation. There are devices, such as color controllers, but this is not intended for surveillance.

[0004]

When a register mark of a printed matter running at a high speed or a register shift of a picture is displayed as a still image on the screen, the size of the displayed register mark or a predetermined portion of the picture or a reference position is changed. I didn't understand the deviation.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a misregistration monitoring device capable of displaying a scale together with a predetermined portion of a registration mark or a picture on a screen.

[0006]

In order to achieve the above object, a multicolor pattern printed in a traveling direction at a predetermined pitch is provided, and a position where a predetermined portion of the pattern passes on the same plane as the traveling printed matter. And a transparent scale provided in
Flashing means for flashing a range including the scale, imaging means for imaging the range irradiated by the flashing means, timing when a predetermined portion of the pattern passes through the position of the scale, and flashing A timing control circuit for generating a timing signal for causing the image pickup means to take an image; an image memory for storing image pickup data of the image pickup means based on the timing signal; and a display device for displaying the contents of the image memory. is there.

As the scale, a scale having a scale in a direction perpendicular to the traveling direction of the printed matter is used.

Further, as the scale, a grid scale in which one of the running direction of the printed matter and the scale is the same direction is used.

[0009]

The predetermined portions of the pattern printed on the printed matter are printed at a predetermined pitch, and when the predetermined portions of the pattern pass the position of the image pickup means, a timing signal is generated from the timing control circuit, which causes A flash of light from the flash means illuminates the printed matter and a transparent scale provided on substantially the same plane as the printed matter. The image pickup means also inputs a timing signal and picks up an image of a predetermined portion and the scale of the picture illuminated by the flash light.
The picked-up image data is stored in the image memory based on the timing signal, read out, and displayed on the display device. Since the scale is displayed on the display screen together with the predetermined portion of the design, the size of the predetermined portion of the design and one of the scales of the scale are used as the reference position to shift the predetermined portion of the design from the reference position. Can be seen on the display screen. In addition, the reference position is a position that is assumed in design such that a predetermined portion of the pattern passes through the position,
The automatic register control device controls so that a predetermined portion of the pattern comes to this position.

When a scale having a scale perpendicular to the running direction of the printed matter is used as the scale, it is possible to monitor the print deviation in the direction perpendicular to the running direction.

When a grid scale in which one of the running direction and the scale is the same is used as the scale, it is possible to monitor the printing deviation in the running direction and in the direction perpendicular thereto.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. As an example, an example of monitoring a portion of a register mark as a predetermined portion of a design will be described. FIG. 1 is a block diagram showing the configuration of the first embodiment of the present invention. The register mark 2 is printed on the printed matter 1 at a constant pitch and is running at high speed in the arrow direction. The transparent scale 3 is provided on the television camera 7 side, which is an image pickup means, at a position apart from the reference position of the plate cylinder 4 by a predetermined distance, and on substantially the same surface as the printed matter 1. The plate cylinder 4 prints the same pattern per one rotation, but the register mark 2 is also printed at the end of the pattern. Therefore register mark 2
Appears as the pitch of the plate cylinder 4 or a fraction thereof. The encoder 5 is directly connected to the rotary shaft of the plate cylinder 4 and generates a predetermined number of pulses per one rotation of the plate cylinder 4.

A flash light source 6, which is flash means, irradiates the scale 3 and the printed material 1 around it with flash light in accordance with a timing signal described later. The television camera 7 captures an image of the portion illuminated by the flash according to the timing signal. The timing control circuit 8 generates a timing signal based on the pulse of the encoder 5 when the register mark comes to the position of the scale 3. The image memory 9 writes the image pickup data of the television camera 7 by a signal based on a timing signal and displays it on the display device 10.

FIG. 2 is a diagram for explaining the function of the encoder 5. It is assumed that the encoder 5 generates, for example, 1000 pulses when the plate cylinder 4 makes one rotation, that is, when the encoder 5 makes one rotation. In other words, if the perimeter of the plate cylinder is divided into 1000, and the plate cylinder 4 is such that the registration mark 2 is printed at the 300th division, the registration mark appears at the position A at the 300th pulse, and 1000 pulses. The register mark moves to the position of B in the eye. When the radius of the plate cylinder 4 is R, the AB distance L is expressed by the following equation. L = 2πR × (1000-300) / 1000 (1)

Further, when the number of pulses corresponding to the distance between the reference position of the plate cylinder 4 of the encoder 5 and the register mark is n (≧ 300), the distance Ln between the axial center of the plate cylinder 4 and the register mark 2 is expressed by the following equation. To be done. Ln = 2πR (n-300) / 1000 (2)

Since the register mark is printed every 1000 pulses, by counting the number of pulses n, it is possible to know at what distance the register mark is from the reference position of the plate cylinder 4 from the equation (2). From the number of pulses and the distance between the reference position scale 3 of the plate cylinder 4 and the number of pulses that the register mark 2 passes through the position of the scale 3, the timing control circuit 8 can output a timing signal.

FIG. 3 is a diagram for explaining the influence of the distance between the printed matter 1 and the scale 3. It is desirable that the scale 3 be as close to the printed matter 1 as possible, but since the printed matter 1 flutters because it travels at a high speed, a distance is provided between the scale 3 and the printed matter 1 so that they do not come into contact with each other. On the other hand, if the distance between the printed matter 1 and the scale 3 is too large, it becomes difficult for the lens of the television camera 7 to focus both of them at the same time, so it is necessary to keep the distance within the range of the depth of focus. In order to make the depth of focus deep, there is a margin of light quantity, and the aperture of the lens of the TV camera 7 is narrowed down for shooting.

As described above, since there is a slight distance between the printed matter 1 and the scale 3, it is necessary to make the scale scale smaller in order to correct the dimensions. Figure 3
From the dimensions of D, d, w1 and w2 shown in, the scale factor M of the scale 3 is expressed by the following equation. M = w2 / w1 = (D−d) / D (3) However, the distance D between the printed matter 1 and the lens of the television camera 7
Is sufficiently larger than the distance d between the printed matter 1 and the scale 3 and the correction is not necessary, the scale may not be corrected.

FIG. 4 is a diagram for explaining a measure for preventing halation due to illumination. Although the scale 3 having gloss is used in the present embodiment, the specularly reflected light of the light source is incident on the television camera 7 due to the reflection illumination and causes halation to obstruct the image, so that it is shown in FIG. As described above, the scale 3 is angled to let the specular reflection light of the flash escape to the outside of the field of view of the television camera 7, or the flash light source 6 is obliquely illuminated as shown in FIG. .

FIG. 5 shows a scale setting device having a mechanism for setting the position of the scale 3. The TV camera 7 is covered with a light shielding hood 11, and a vertical slide rail 12 for moving the scale 5 in the vertical direction is provided on the front surface of the light shielding hood 11 so that the scale 3 can be fixed with a lock nut 13. The scale 3 and the lock nut 13 are engaged with each other by an elongated hole 14 provided in the scale 3 so that the scale 3 can be moved in the left and right directions. If the scale 3 is unnecessary, it may be retracted to the upper end or the lower end.

In the first embodiment, by registering the planned position where the register mark 2 passes on the scale 3, the register mark 2
It is possible to easily monitor the deviation in the direction perpendicular to the traveling direction of the vehicle on the display screen.

Next, a second embodiment will be described. FIG. 6 is a block diagram showing the configuration of this embodiment. In this embodiment, the scale 3 is replaced with a transparent grid scale 15 in comparison with the first embodiment, and the flash light source 6 is arranged on the opposite side with the television camera 7 and the printed material 1 interposed therebetween, and the light diffusion plate 16 is provided on the flash light source 6 side. The other parts are the same as those in the first embodiment. The light diffusion plate 16 is provided in order to prevent the transparent light of the flash from directly inputting to the television camera 7 by diffusing the flash. Further, the grid scale 15 can display the registration mark shift in the traveling direction and the direction perpendicular thereto on the screen of the display device 10.

In FIG. 6, a deviation in the direction perpendicular to the running direction of the register mark 2 can be monitored by a scale in the direction perpendicular to the running direction of the grid scale 15, that is, a vertical scale, and the running of the register mark 2 in the running direction scale. You can monitor deviations in direction. In the monitoring of the deviation in the traveling direction, as described in FIG. 2, the pulse count value of the encoder 5, the plate cylinder reference position, and the distance between the register marks correspond to each other, so that the grid scale 15 is located at a certain distance position. The scale is adjusted and a still image of the count value corresponding to this distance is displayed on the display screen. The deviation between a certain scale and the register mark 2 at this count value is monitored. As a result, it is possible to simultaneously monitor the deviation of the register mark 2 in two orthogonal directions.

[0024]

As is apparent from the above description, according to the present invention, by displaying the predetermined portion of the design and the scale on the same screen, the shift of the predetermined portion of the design can be easily monitored.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a first embodiment.

FIG. 2 is a diagram illustrating the operation of an encoder.

FIG. 3 is a diagram illustrating an influence of a distance between a printed matter and a scale.

FIG. 4 is a diagram illustrating a method of preventing halation.

FIG. 5 is a diagram illustrating a scale setting position adjusting mechanism.

FIG. 6 is a block diagram showing a configuration of a second embodiment.

[Explanation of symbols]

 1 Printed matter 2 Registration mark 3 Scale 4 Plate cylinder 5 Encoder 6 Flash light source 7 TV camera 8 Timing control circuit 9 Image memory 10 Display device 15 Grid scale 16 Light diffusion plate

Claims (3)

[Claims] 1. A transparent scale having a multi-color pattern printed in a traveling direction at a predetermined pitch, the transparent scale being provided at a position where a predetermined portion of the pattern passes on a plane substantially flush with the traveling printed matter, and the scale. Flashing means for irradiating the range including the flashing area, an imaging means for imaging the range irradiated by the flashing means, a timing at which a predetermined portion of the pattern passes through the position of the scale, and for irradiating the flashing area with the imaging A timing control circuit for generating a timing signal for causing the image capturing means to capture an image, an image memory for storing image capturing data of the image capturing means based on the timing signal, and a display device for displaying the contents of the image memory. Misregistration monitoring device. 2. A misregistration monitoring device, wherein a scale having a scale in a direction perpendicular to the traveling direction of the printed matter is used as the scale. 3. A misregistration monitoring device using a grid scale in which one of the running direction and the scale of the printed matter is the same direction as the scale.