JP2916601B2 - Method and apparatus for adjusting position and amplification of detector of printed matter based on two-dimensional image - Google Patents

Description

The present invention relates to a method and an apparatus for adjusting a position and an amplification degree of a detector for detecting a printed matter when inspecting the printed matter.

[Conventional technology]

Two detectors detect the same part of two patterns of a printed matter composed of a plurality of the same patterns, and the position of these detectors is adjusted by the difference between the electric signals of the two detectors and the amplification degree is adjusted by each detector. While observing the electric signals of the detectors with an oscilloscope, the adjustment state of the two detectors is determined from the change in the waveform.

[Problems to be solved by the invention]

In the prior art, the adjustment state of the two detectors has to be determined based on the change in the waveform of the electric signal, and the adjustment requires specialized knowledge, experience, and time. But nonetheless, the adjustments were not satisfactory.

The present invention seeks to provide a method for adjusting two detectors without requiring specialized knowledge, experience and time.

[Means for solving the problem]

In order to achieve the above object, the position adjustment for adjusting the two detectors to detect the same part of the two patterns and the amplification adjustment for adjusting the output voltages of the amplifiers of the two detectors to match are performed. The electric signal generated when the two detectors do not detect the same part of the two patterns and the electric signal generated when the output voltages of the amplifiers of the two detectors do not match each other as two-dimensional images on the monitor television. The position is adjusted by moving the detector and the amplification is adjusted by changing the constants of the electronic circuit so that the image is not displayed while the image is displayed and the image is observed.

[Action]

Since the adjustment state of the two detectors can be directly observed by the two-dimensional image displayed on the monitor television, the adjustment of the two detectors can be performed reliably and easily, even by a person without specialized knowledge and experience. In addition, the adjustment time can be reduced.

〔Example〕

FIG. 1 illustrates the position adjustment of the detector. Two identical patterns (2) and (2 ') of a moving printed matter (1) composed of a plurality of the same patterns are detected by two detectors (3) and (3') to generate electric signals. After amplification by the amplifiers (4) and (4 '), the difference between the two electric signals is obtained by the arithmetic unit (5), and the difference is digitized by the analog / digital conversion unit (6). ) And displayed on the monitor television (8) as a two-dimensional image. Second
The figure shows the difference between the electric signals of the two detectors (3) and (3 ') when the two detectors (3) and (3') do not detect the same part of the two patterns. This is an example in which an image is displayed on a monitor television (8). The dark area (9) of the image indicates an area where the difference between the electric signals of the two detectors (3) and (3 ') is small, and the light area (10) is the two detectors (3) and (3'). 3 shows a region where the difference between the electric signals is large.
FIG. 3 shows a state in which the positions of the two detectors (3) and (3 ') are adjusted to detect the same part of the two patterns (2) and (2'). Three detectors (3),
This is an example in which the difference of the electric signal of (3 ') is displayed on the monitor television (8). At this time, the difference between the electric signals of the two detectors whose positions are adjusted so as to detect the same position of the two pictures (2) and (2 ') is ideally zero, and the monitor television (8) The entire screen is a dark area (9), but in an actual printed matter, the bright area (10) may not disappear due to a printing position shift or the like. In this case, the state in which the bright area (10) is the smallest is determined to be the best adjustment point.

On the other hand, with respect to the amplification degree adjustment, an operation of changing the constant of the electronic circuit is performed, and similarly, the state where the bright area (10) is minimized is determined as the best point of the adjustment.

〔The invention's effect〕

1. Even those who do not have specialized knowledge and experience can adjust the position and amplification of the two detectors reliably and easily, and can shorten the adjustment time.

2. While the device for inspecting printed matter is operating, the inspection status can be constantly monitored by observing the difference between the electric signals of the two detectors displayed on the monitor television.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention. FIG. 2 is a diagram showing an example in which a difference between electric signals of two detectors is displayed as an image on a monitor television in a state where the two detectors do not detect the same portion of two patterns. FIG. 3 shows an example in which the difference between the electric signals of the two detectors is displayed on a monitor television in a state where the positions of the two detectors are adjusted to detect the same part of the two patterns. FIG. 1 Printed matter, 2 ', picture, 3, 3', detector, 4, 4 ', amplifier, 5, arithmetic unit, 6, analog-digital conversion unit, 7, memory, 8: Monitor TV, 9: Dark area, 10: Light area.

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁶ , DB name) G06T 1/00 G06T 7/00-7/60

Claims (2)

(57) [Claims] 1. A printed matter is inspected by detecting two identical parts of a printed matter composed of a plurality of identical pictures with two detectors and comparing a difference between both electric signals with a reference value. In the two detectors, position adjustment for adjusting the two detectors to detect the same portion of the two patterns and amplification adjustment for adjusting the output voltages of the amplifiers of the two detectors to match are performed on the two detectors. The resulting electric signal difference is displayed on a monitor television as a two-dimensional image, and the position adjustment moves the detector and the amplification adjustment changes the constant of the electronic circuit so that the image is not displayed while observing the image. And a method of adjusting the position of a detector and an amplification factor of a printed matter based on a two-dimensional image. 2. A monitor television for detecting two identical parts of two patterns of a printed matter composed of a plurality of identical patterns, and a difference between electric signals generated in the two detectors as a two-dimensional image. And position adjustment for adjusting the two detectors to detect the same portion of the two patterns and amplification adjustment for adjusting the output voltages of the amplifiers of the two detectors to match the image of the monitor television. The position adjustment is performed by moving the detector so that the image is not displayed while observing the image. Degree adjustment device.