JPH08285786A - Foreign matter inspection equipment for plastic board - Google Patents

Abstract

PURPOSE: To obtain accurate inspection results while shortening the inspection time significantly by picking up the image of an objective plastic board and deciding whether a foreign matter is present and determining the size thereof, if any. CONSTITUTION: A transfer unit 2 feeds an objective plastic board 7 to an image input unit 5 which then picks up the image of the plastic board 7. An inspection unit 6 decides whether a foreign matter is present in the plastic board 7 and a marking unit 3 is controlled based on the decision results to put a mark, indicative of presence or absence of foreign matter, on the plastic board 7 before it is fed out by means of a transfer unit 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic plate foreign matter inspection device for inspecting a transparent plastic plate or a colored plastic plate for foreign matter.

[0002]

2. Description of the Related Art When judging the quality of a plastic material used as a material for various plastic molded products, it is usual to make a plastic material into a plate shape and visually inspect by an inspector whether there is a foreign substance in the plastic plate. If there is a foreign substance, the size and the number of the foreign substance are judged to judge the quality of the plastic material.

[0003]

However, in the above-mentioned conventional method for inspecting the plastic material, the visual inspection by the inspector is carried out to find out whether or not there is any foreign matter in the plastic sheet. It took too much time and the inspection result became inaccurate due to oversight of the inspector.

In view of the above circumstances, the present invention can photograph a plastic plate to be inspected and determine the presence or absence of foreign matter and its size, thereby significantly reducing the inspection time of the plastic plate. While being able to
An object of the present invention is to provide a plastic plate foreign matter inspection device that can obtain accurate inspection results.

[0005]

In order to achieve the above object, a plastic plate foreign matter inspection device according to the present invention is, in claim 1, an image input device for capturing and photographing a plastic plate to be inspected for foreign matter. An inspection device for determining at least one of the presence or absence of a foreign matter portion and its size based on each pixel value of the image signal of the plastic plate obtained by this image input device, and the determination result of this inspection device Is provided by at least one of marking and screen display on the plastic plate.

According to a second aspect of the present invention, in the plastic plate foreign matter inspection device according to the first aspect, the image input device holds the plastic plate and moves it in the X and Y directions, and the XY stage mechanism. An imaging mechanism that divides the plastic plate moved in the X and Y directions by a stage mechanism into small inspection target areas and takes an image, and is arranged on the lower surface side of the XY stage mechanism.
A lower surface side illumination mechanism that illuminates the plastic plate held by the Y stage mechanism from the lower surface side, and a plastic plate held by the XY stage mechanism that is arranged on the upper surface side and illuminates the plastic plate held by the XY stage mechanism from the upper surface side. It is characterized by including an upper surface side illumination mechanism.

According to a third aspect of the present invention, in the plastic plate foreign matter inspection device according to the first or second aspect, the inspection device is plastic plate image data corresponding to the image signal of the plastic plate obtained by the image input device. After shading correction with the preset pattern image data for shading correction, the difference with the preset reference value data is calculated to generate foreign substance determination data, and each pixel value of this foreign substance determination data is calculated. On the basis of the above, at least one of the presence or absence of the foreign matter portion and the size thereof is determined.

[0008]

According to the above construction, in the plastic plate foreign matter inspection device according to the first aspect, a plastic plate to be inspected for the presence of foreign substances is captured by the image input device and photographed, and the image is obtained by the inspection device by the image input device. Based on each pixel value of the image signal of the plastic plate, at least one of presence or absence of a foreign matter portion and its size
After determining the one, the marking / display device displays the determination result of the inspection device by at least one of the marking on the plastic plate and the screen display, so that the plastic plate to be inspected is photographed and The presence / absence and size of the plastic plate are determined to significantly reduce the inspection time of the plastic plate and obtain accurate inspection results.

According to a second aspect, in the plastic plate foreign matter inspection device according to the first aspect, the image input device holds the plastic plate by an XY stage mechanism and moves the plastic plate in the X and Y directions, The plastic plate is illuminated from the lower surface side by the lower surface side illumination mechanism arranged on the lower surface side of the XY stage mechanism, and the plastic plate is illuminated from the upper surface side by the upper surface side illumination mechanism arranged on the upper surface side of the XY stage mechanism. While doing so, the plastic plate to be inspected is photographed by dividing the plastic plate moved in the X and Y directions by the XY stage mechanism by the photographing mechanism into small inspection target areas, and photographing. By determining the presence or absence of foreign matter and its size, the inspection time of the plastic plate can be shortened significantly. To obtain accurate test results.

According to a third aspect of the present invention, in the plastic plate foreign matter inspection device according to the first or second aspect, the plastic plate image corresponding to the image signal of the plastic plate obtained by the image input device by the inspection device. After shading correction of the data with preset pattern image data for shading correction, the difference with the preset reference value data is calculated to generate foreign substance determination data, and each pixel of the foreign substance determination data is calculated. Based on the value, at least one of the presence or absence of a foreign matter portion and its size is determined, and the plastic plate to be inspected is photographed to determine the presence or absence of a foreign matter and its size. The inspection time of the plastic plate is greatly shortened and the accurate inspection result is obtained.

[0011]

1 is a block diagram showing an embodiment of a plastic plate foreign matter inspection apparatus according to the present invention.

The plastic plate foreign matter inspection device 1 shown in this figure has a carry-in device 2, a marking device 3, and a carry-out device 4.
The image input device 5, the conveyance unit control device 18, and the inspection device 6 are provided, and after the plastic plate 7 to be inspected is carried into the image input device 5 by the carry-in device 2, the image input device 5 is carried out. The transmission image or reflection image of the plastic plate 7 is taken in by the inspection device 6, the inspection device 6 determines whether there is a foreign substance in the plastic plate 7, and the marking device 3 is controlled based on this determination result to determine whether there is a foreign substance. After marking etc. on the plastic plate 7, it is carried out by the carry-out device 4.

The carry-in device 2 takes in the plastic plates 7 discharged one by one from a magazine device (not shown) in which the plastic plates 7 are set in units of a predetermined number of sheets, for example, 14 sheets, and the image is input into the image input device. It is equipped with a roller conveyer 8 for carrying to the 5 side, and takes in the plastic plate 7 every time it is discharged from the magazine device, and carries it to the image input device 5.

Further, the marking device 3 takes in the plastic plate 7 discharged from the image input device 5 and, based on the marking command output from the main processing device 15 via the transporting part control device 18, the plastic plate 7 is printed. When there is a foreign substance in the sheet, marking is performed on the designated position of the plastic plate 7 and the sheet is carried out to the carry-out device 4.

The carry-out device 4 is equipped with a roller conveyor 9 for taking in the plastic plate 7 discharged from the marking device 3 and conveying it to the stacking device (not shown) side.
Is taken out and conveyed to the stacking device.

Further, the image input device 5 holds the plastic plate 7 sent by the carry-in device 2 and performs positioning based on an instruction from the transfer section control device 18, and this XY stage mechanism. When the plastic plate 7 held by 10 is transparent, it is held by the XY stage mechanism 10 and the transmission strobe illumination mechanism 11 that illuminates the plastic plate 7 from below based on the instruction from the inspection device 6. When the plastic plate 7 is colored, the reflection strobe illumination mechanism 12 that illuminates the plastic plate 7 from above based on the instruction from the inspection device 6, and the diaphragm according to the instruction from the inspection device 6 The microscope mechanism 13 for capturing the optical image of the plastic plate 7 and the microscope mechanism 13 for capturing the optical image. And a CCD area sensor mechanism 14 to be supplied to the inspection unit 6 of the optical image written into an electric signal (image signal).

Then, after fixing the plastic plate 7 sent by the carry-in device 2 by the XY stage mechanism 10, as shown in FIG.
While moving the plastic plate 7 in the longitudinal direction and the width direction, the transmission strobe illumination mechanism 11 or the reflection strobe illumination mechanism 12 illuminates the plastic plate 7, and the microscope mechanism 13 illuminates an optical image of the plastic plate 7. While keeping the constant, CC
The plastic plate 7 is formed by the D area sensor mechanism 14.
The optical image of each inspection region is converted into an image signal and supplied to the inspection device 6.

The inspection device 6 processes the operation of the carry-in device 2, the marking device 3, the carry-out device, the image input device 5, and the transport unit controller 18 which controls the operation of the XY stage mechanism 10 and the CCD area sensor mechanism 14. A main processing device 15 that processes an output image signal, and a printer device that, when a print command is output from the main processing device 15, captures print information output together with the print command and prints it out. 17 and a monitor device 16 that takes in a monitor signal output from the main processing device 15 and displays the image of the plastic plate 7 and the inspection status on the screen. And the operation of the image input device 5 are controlled so that the plastic plate 7 to be inspected is photographed, and the image signal obtained by this is captured. After determining the presence or absence of the foreign matter and the portion where the foreign matter exists, the marking device 3 is controlled to mark the portion of the plastic plate 7 where the foreign matter exists, for example, the plastic plate 7 as shown in FIG. In each of the inspection areas constituting the above, the non-inspection portion of the block including the area where the foreign substance exists is marked, and the carry-out device 4 is controlled to carry out the marked plastic plate 7.

In this case, the main processing unit 15 uses the CC
The image signal output from the D area sensor mechanism 14 is A /
An A / D conversion circuit 20 (see FIG. 4) that performs D conversion (analog / digital conversion) to generate plastic plate image data.
And a keyboard interface circuit that takes in key signals output from a keyboard device (not shown) and generates various commands and various data, and various commands and various data generated by this keyboard interface circuit. CP that performs various information processing based on
The U circuit and the display data generated by the CPU circuit are fetched to generate a display signal, and the display signal is supplied to a CRT device (not shown) or the monitor device 16.
And an RT interface circuit.

Further, the main processing unit 15 is the CPU
A ROM circuit 21 (see FIG. 4) in which a program for defining the operation of the circuit and various constant data are stored, and the C
The RAM circuit 22 (see FIG. 4) used as a work area of the PU circuit, the transfer control command, the marking command, the diaphragm command, etc. output from the CPU circuit are taken in,
A large-capacity storage mechanism that is configured by an output interface circuit that supplies this to the transfer unit controller 18 and a hard disk device, and that is used as a large-capacity storage area of the CPU circuit, and print data that is output from the CPU circuit. And a printer interface circuit for supplying the same to the printer device 17.

Then, the CCD area sensor mechanism 14
When processing the image signal output from the above, the image signal is processed in the following procedure based on the program stored in the ROM circuit 21 or the mass storage mechanism to detect the presence or absence of foreign matter and the presence of foreign matter. The part to be performed is determined.

First, as shown in FIG. 4, an A / D conversion circuit 20 is provided.
The image signal output from the CCD area sensor mechanism 14 is fetched by the A / D converter, and the image signal is A / D converted to plastic plate image data, which is then stored in the frame memory circuit 23 in the RAM circuit 22.

Next, the plastic plate image data stored in the frame memory circuit 23 is read in a FIFO format (first-in / first-out format), and density conversion is performed as shown in FIG. 5 (a).

Before starting the inspection, the pattern image data for shading correction is read from the file stored in the hard disk device, the pattern image data is read from the stored pattern memory circuit 24, and the pattern image data is read. Density conversion is performed as shown in FIG. The plastic plate image data for which the density conversion has been completed is subtracted from the pattern image data for shading correction which has also been subjected to the density conversion, and the plastic plate image data is subjected to shading correction.

In this case, the plastic plate image data stored in the frame memory circuit 23 has a central portion as shown in FIG. 6A due to the luminous intensity distribution characteristics of the transmission strobe illumination mechanism 11 and the reflection strobe illumination mechanism 12. The pattern image data stored in the pattern memory circuit 24 is bright and the surrounding area is dark, and the pattern image data stored in the pattern memory circuit 24 corresponds to the luminous intensity distribution characteristics of the transmission strobe illumination mechanism 11 and the reflection strobe illumination mechanism 12. 6 (b)
As shown in FIG. 6, the central portion is bright and the peripheral portion is dark. Therefore, by subtracting the pattern image data from the plastic plate image data, the pattern image data shown in FIG.
It is possible to correct the luminous intensity distribution characteristics of the transmission strobe illumination mechanism 11 and the reflection strobe illumination mechanism 12, which the plastic plate image data has, as shown in FIG.

Next, in order to create data showing a value corresponding to the brightness of a portion in the plastic plate 7 where there is no foreign matter (for example, data showing a value "100") from 0 data, the data shown in FIG. The density conversion shown is performed, reference value data is created, and the shading-corrected plastic plate image data is subtracted from the reference value data.
The density conversion shown in (d) is performed to generate foreign matter determination data.

In this case, the shading-corrected plastic plate image data shows a standard value of "140" in a portion having no foreign matter as shown in FIG. 6 (c), and a standard value "" in a portion having a foreign matter. Since the value is lower than 140 ", for example, the value" 70 ", by subtracting the shading-corrected plastic plate image data from the reference value data, only the portion where the foreign matter exists as shown in FIG. It is possible to generate foreign object determination data with a high value and a low value in other portions.

From the foreign matter determination data, the position and area (number of pixels) of the foreign matter can be determined,
A mark command is generated based on the determination result, and the marking device 3 is controlled to mark the portion of the plastic plate 7 corresponding to the inspection area in which the foreign matter exists.

Thus, in this embodiment, after the plastic plate 7 to be inspected is carried into the image input device 5 by the carry-in device 2, the image of the plastic plate 7 is taken in by the image input device 5 and the inspection device It is determined whether there is a foreign substance in the plastic plate 7 at 6, and the marking device 3 is controlled based on the determination result to mark the presence or absence of the foreign substance on the plastic plate 7, and then the carrying-out device 4 performs the marking. Since the plastic plate 7 is carried out, it is possible to take a picture of the plastic plate 7 to be inspected and determine the presence or absence of foreign matter, its size, etc. Therefore, the inspection time of the plastic plate 7 can be greatly shortened. In addition, it is possible to obtain accurate inspection results.

Further, in this embodiment, for the plastic plate image data, shading correction using the pattern image data and extraction of the foreign substance portion using the reference data are sequentially performed to generate the foreign substance determination data. Therefore, it is possible to process the plastic plate image data in a pipeline format with a simple data processing configuration, thereby increasing the processing speed and determining the presence or absence of foreign matter and its size in real time. it can.

Further, in this embodiment, the plastic plate 7 held by the XY stage mechanism 10 is illuminated from the lower surface side by the transmission strobe illumination mechanism 11 or from above by the reflection strobe illumination mechanism 12. Therefore, even if the plastic plate 7 is transparent or colored, the image of the plastic plate 7 can be captured and processed.

[0032]

As described above, according to the present invention, in Claims 1, 2 and 3, it is possible to photograph the plastic plate to be inspected and determine the presence or absence of foreign matter and its size. As a result, the inspection time of the plastic plate can be greatly shortened and an accurate inspection result can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a plastic plate foreign matter inspection device according to the present invention.

FIG. 2 is a schematic view showing an example of an inspection area of a plastic plate to be inspected by the plastic plate foreign matter inspection device shown in FIG.

FIG. 3 is a schematic diagram showing a marking example of a plastic plate inspected by the plastic plate foreign matter inspection device shown in FIG.

FIG. 4 is a schematic diagram showing an example of a determination process of the presence / absence of a foreign substance and a portion in which the foreign substance exists in the main processing device shown in FIG.

5 is a schematic diagram showing a characteristic example of each data in the main processing device shown in FIG. 1. FIG.

6 is a schematic diagram showing an example of the relationship between the position of each data and the density value in the main processing device shown in FIG.

[Explanation of symbols]

 1 plastic plate foreign matter inspection device 2 carry-in device 3 marking device (marking / display device) 4 carry-out device 5 image input device 6 inspection device 7 plastic plate 8 roller conveyor 9 roller conveyor 10 XY stage mechanism 11 transmission strobe lighting mechanism (bottom side illumination) Mechanism) 12 Reflected strobe illumination mechanism (upper surface side illumination mechanism) 13 Microscope mechanism (imaging mechanism) 14 CCD area sensor mechanism (imaging mechanism) 15 Main processing unit 16 Monitor device (marking / display device) 17 Printer device 18 Transport unit control Device 20 A / D conversion circuit 21 ROM circuit 22 RAM circuit 23 Frame memory circuit 24 Pattern memory circuit

Claims (3)

[Claims] 1. An image input device for capturing and photographing a plastic plate to be inspected for the presence of foreign matter, and the presence or absence of a foreign substance portion based on each pixel value of the image signal of the plastic plate obtained by the image input device. An inspection device for determining at least one of the sizes, and a marking / display device for displaying the determination result of the inspection device by at least one of marking on the plastic plate and screen display are provided. A foreign substance inspection device for plastic plates. 2. The plastic plate foreign matter inspection device according to claim 1, wherein the image input device holds a plastic plate and moves the plastic plate in the X and Y directions, and the XY stage mechanism.
An imaging mechanism that divides the plastic plate moved in the X and Y directions by a stage mechanism into small inspection target areas and takes an image, and is arranged on the lower surface side of the XY stage mechanism and is held by the XY stage mechanism. A lower surface side illumination mechanism that illuminates a plastic plate from the lower surface side, and an upper surface side illumination mechanism that is disposed on the upper surface side of the XY stage mechanism and that illuminates the plastic plate held by the XY stage mechanism from the upper surface side. A plastic plate foreign matter inspection device characterized by being provided. 3. The plastic plate foreign matter inspection device according to claim 1, wherein the inspection device presets plastic plate image data corresponding to the image signal of the plastic plate obtained by the image input device. After performing shading correction with the pattern image data for shading correction, the difference between the reference value data set in advance is calculated to generate foreign substance determination data, and based on each pixel value of the foreign substance determination data,
A plastic plate foreign matter inspection device characterized by determining at least one of the presence or absence of a foreign matter portion and its size.