KR101268549B1 - Vision inspection apparatus using multiple grid pattern and polarizing plates - Google Patents

Abstract

In the vision inspection apparatus using the polarizing plate and the multi-lattice pattern according to the present invention, after taking a test object assembled or mounted in a part assembly process with a camera, the photographed image is compared with a pre-input target image to check whether the test object is good or bad. A vision inspection apparatus for determining a light source, comprising: a stage unit for fixing or transporting an inspection object to an inspection position, an upper portion of the stage unit, an illumination unit providing illumination to the inspection object, and positioned at a center of the illumination unit A central camera unit for obtaining a two-dimensional shape of the inspection object, a plurality of side camera units disposed on the side of the central camera unit, and a plurality of grids disposed between the cameras and the cameras of the side camera unit at the side of the central camera unit. The inspection by reading the pattern irradiation unit and the image taken by the central camera unit And a control unit controlling the stage unit, the grid pattern irradiation unit, and the camera unit, wherein the grid pattern irradiation unit and the central camera unit are provided with a polarizing plate, and the grid pattern irradiation unit It is characterized in that it is configured to irradiate the grid pattern having a period of different intervals.

Description

VISION INSPECTION APPARATUS USING MULTIPLE GRID PATTERN AND POLARIZING PLATES

The present invention relates to a vision inspection apparatus, and more particularly, to adjust the intensity of light used for vision inspection, and to perform a vision inspection by performing a vision inspection using a wider grid pattern and a narrower grid pattern, faster vision inspection The present invention relates to a vision inspection apparatus using a multi-grid pattern that can be performed accurately.

In general, Surface Mounting Technology (SMT) for assembling surface mount components on a printed circuit board (PCB) is a technology for miniaturizing / integrating Surface Mounting Device (SMD) Development of precise assembly equipment for precise assembly, and techniques for operating various assembly equipment.

Surface mount lines consist of equipment such as surface mounters and vision inspection equipment. The surface mount machine mounts surface mount components on a printed circuit board and supplies various surface mount components supplied in the form of Tape, Stick, Tray from the component feeder to the mounting position on the printed circuit board. .

The vision inspection apparatus inspects the mounting state of the surface mounted component before or after the soldering process of the surface mounted component is completed, and transfers the printed circuit board to the next process according to the inspection result.

As shown in FIG. 1, a conventional vision inspection apparatus includes an illumination unit 110 to which light is irradiated using a lamp and the like, and image information of various components mounted on an inspection object installed on the illumination unit 110. And a half mirror 130 for reflecting the light from the illumination unit 110 to photograph and reflecting the light from the illumination unit 110 to transmit the shape of the inspection object to the camera unit.

Here, the lighting unit 110 is arranged in the housing 140 by arranging a plurality of lamps, and, when irradiating the light to the inspection object to supply power to the plurality of lamps to irradiate light.

On the other hand, in the conventional vision inspection method, when the inspection object is horizontally transported through the conveyor, the initial position is adjusted by the position adjusting device, and after the adjustment is completed, when irradiated with light through the grid on the LED part or the printed circuit board, the irradiated By analyzing the shadow shape that light is reflected on the surface of the inspection object, the three-dimensional height is measured.

Then, by calculating the photographing part and comparing with the reference value, the inspection of the good / bad of the component mounting associated with the height, or the presence / absence of the mounting of the surface mounting component.

All of the above inspection methods measure a two-dimensional shadow shape and calculate a three-dimensional height by using a trigonometric function.

Therefore, it is very important for the vision inspection apparatus using the structured light that the shadow pattern formed by the irradiated light is clearly photographed.

By the way, in the case of a semiconductor component mounted on a PCB substrate or the like, the reflected light becomes too bright due to scattering of light in the metal part such as the lead part or the solder part.

These factors interfere with accurate height measurement of parts and inspection of uninserted and lifted parts.

In addition, as shown in FIG. 2, when the grid object is irradiated with a plaid light onto a test object having a height and is photographed in plan view, the height of the test object is relatively higher than the interval between the grid patterns. It is not possible to distinguish which of (1, 2, 3) and the bottom lattice 1-1, 2-1, 3-1 are the same lattice in the first place.

Therefore, such a factor may cause an error in height inspection, which increases the number of image photographs required for height measurement in order to eliminate such an error, and complicates the height calculation process based on the image photograph. This delays the overall time spent on the system.

Meanwhile, in the conventional vision inspection apparatus, a half mirror provided for capturing an image while reflecting light is disposed in front of the center camera unit, thereby preventing a clearer image.

In addition, since the light from the lighting unit is directly irradiated on the surface of the inspection object, there is a problem that the portion of the light is directly irradiated by overlapping the light is relatively dark while the portion where the light density is low.

And, since a configuration such as a laser, a camera for recognizing whether or not the inspection target substrate is mounted in the correct position in the central camera portion is accommodated, the type of the overall configuration accommodated in the housing for accommodating the central camera, The increase in size and weight causes inconvenience in maintenance.

The present invention has been made to solve the above problems, an object of the present invention is to provide a vision inspection apparatus that can effectively reduce the intensity of light generated from the metal surface of the component to perform a more accurate inspection .

Another object of the present invention is to provide a vision inspection apparatus capable of measuring the height of an inspection object quickly and accurately.

Still another object of the present invention is to provide a vision inspection apparatus capable of improving the uniformity of light irradiated onto a surface of an inspection object.

Still another object of the present invention is to provide a vision inspection apparatus capable of capturing a clearer image by removing a half mirror disposed in front of a central camera unit.

Vision inspection apparatus using a polarizing plate and a multi-grid pattern according to the present invention for achieving the above object, by comparing the photographed image with a pre-input target image after photographing the inspection object assembled or mounted in the assembly process A vision inspection apparatus for determining good or bad of an inspection object, comprising: a stage unit for fixing or transferring the inspection object to an inspection position, an illumination unit positioned at an upper portion of the stage unit, and providing illumination to the inspection object; A central camera unit positioned at the center of an illumination unit to obtain a two-dimensional shape of an inspection object, a side camera unit disposed in a plurality of sides of the central camera unit, and between the camera of the side camera unit and the camera at the side of the central camera unit; A plurality of grid pattern irradiation unit disposed in the, and taken by the central camera unit And a control unit for controlling the stage unit, the lattice pattern irradiation unit, and the camera unit by reading an image to determine whether the inspection object is good or bad, and the grid pattern irradiation unit and the central camera unit are provided with a polarizing plate. The grid pattern irradiation unit is configured to irradiate grid patterns having periods of different intervals.

Here, the grid pattern irradiation unit may include any one of a liquid crystal panel or a micromirror module.

Preferably, the grid pattern irradiation unit is composed of a plurality, it is configured to irradiate the grid pattern of a larger period and the grid pattern of a smaller period at the same time or sequentially.

Meanwhile, a light diffusing unit may be disposed in front of the lighting unit.

Here, the lighting unit may include a horizontal lighting unit for irradiating light in the vertical downward direction and an inclined lighting unit for irradiating light in the oblique direction.

Preferably, the plurality of grid pattern irradiation units are disposed to face each other with respect to the central camera unit.

The side camera parts may be disposed to face each other with respect to the center camera part.

On the other hand, the light diffusing unit may be disposed in front of both the horizontal lighting unit and the inclined lighting unit.

In addition, a positioning camera unit for checking the position of the inspection object may be disposed at one side of the central camera unit.

Here, the positioning lighting unit and the half mirror may be disposed in front of the positioning camera unit.

Preferably, the angle between the central camera portion and the grid pattern irradiation portion on the side view is 25 degrees to 45 degrees.

Preferably, the grid pattern irradiator and the polarizing plate disposed in the central camera unit is configured to be rotatable.

Preferably, one of the grid pattern irradiation unit irradiates the grid pattern of a large period with a predetermined color, the other grid pattern irradiation unit to irradiate the grid pattern of a small period with another predetermined color. It is composed.

According to the present invention, the intensity of light generated on the metal surface of the part can be effectively lowered, so that more accurate inspection can be performed.

In addition, the height of the inspection object can be calculated quickly and accurately.

In addition, the uniformity of the light irradiated on the surface of the inspection object can be improved.

In addition, by removing the half mirror disposed in front of the center camera portion, it is possible to capture a clearer image.

1 is a side cross-sectional view of a conventional vision inspection apparatus.
Fig. 2A is a perspective view showing a state in which a lattice pattern is irradiated to the part.
Fig. 2B is a plan view showing a state in which a lattice pattern is irradiated to the part.
3 is a schematic side view of a vision inspection apparatus according to the present invention.
4 is a schematic plan view of a vision inspection apparatus according to the present invention.
5 is a conceptual diagram showing the relationship between the period of the lattice pattern and the height of the parts.

Hereinafter, the configuration of the present invention will be described in detail with reference to the accompanying drawings.

Prior to this, the terms used in the specification and claims should not be construed in a dictionary sense, and the inventor may, on the principle that the concept of a term can be properly defined in order to explain its invention in the best way And should be construed in light of the meanings and concepts consistent with the technical idea of the present invention.

Therefore, the embodiments shown in the present specification and the drawings are only exemplary embodiments of the present invention, and not all of the technical ideas of the present invention are presented. Therefore, various equivalents It should be understood that water and variations may exist.

3 is a schematic side view of a vision inspection apparatus according to the present invention, Figure 4 is a schematic plan view of the vision inspection apparatus according to the present invention.

3 and 4, the vision inspection apparatus using a polarizing plate and a multi-grid pattern in accordance with the present invention, after taking the inspection object (5) assembled or mounted in the process of assembling the camera photographed in advance A vision inspection apparatus for determining the good or bad of the inspection object (5) compared with the target image, comprising: a stage portion (10) for fixing or conveying the inspection object (5) at an inspection position, and the stage portion (10) Located in the upper portion of the illumination unit 20 for providing illumination to the inspection object 5, the central camera unit 30 and positioned in the center of the illumination unit 20 to obtain a two-dimensional shape of the inspection object and And side camera parts 40-2, 40-4, 40-6, and 40-8 arranged on the side of the central camera part, and the side camera part 40-at the side of the central camera part 30. 2, 40-4, 40-6, 40-8) the plurality of cameras disposed between the cameras Grid pattern irradiator 50-2, 50-4, 50-6, 50-8 and a vision processor for determining whether the inspection object is good or bad by reading the image photographed by the central camera unit 30 ( 60, the stage unit 10, the grid pattern irradiation unit 50-2, 50-4, 50-6, 50-8, and the camera unit 30, 40-2, 40-4, 40-6 And a controller 70 for controlling the 40-8, and the polarization plates 33 and 53 are provided on the grid pattern irradiation units 50-2, 50-4, 50-6, and 50-8 and the central camera unit 30. -2, 53-4, 53-6, 53-8 are installed, and the grid pattern irradiation unit 50-2, 50-4, 50-6, 50-8 has a grid pattern having different intervals Characterized in that it is configured to investigate.

Vision inspection apparatus of the present invention is installed to perform the vision inspection before moving to the next process through the conveyor of the preceding equipment, when inspecting the surface-mounted parts of the printed circuit board after the surface mounting work in the surface mounting line .

Such vision inspection apparatus can be installed in a manner that is arranged in the space formed between the conveyor of the line, trailing equipment and the conveyor, can also be used in the form of a single table without being connected to the line, trailing equipment.

Here, the stage unit 10 is a component that provides a space in which the inspected object 5 to be inspected is seated, and a position adjusting unit (not shown) and a high position for adjusting and fixing the position of the inspected object 5. It may be configured to include a government (not shown).

Here, the lighting unit 20 is installed on the upper portion of the stage unit 10 continuously or intermittently along the circumferential direction around the central camera unit 30.

The lighting unit 20 is a component that provides illumination to the inspection object 5 in order to secure accurate image information of the inspection object 5, by placing a plurality of lamps or LED bulbs to the inspection object (5) ) Can be arranged to illuminate from side to side.

The lighting unit 20 includes a horizontal lighting unit 22 and the inclined lighting unit 23.

Here, the horizontal lighting unit 22 is installed on the upper portion of the stage 10 serves to provide the light incident to the inspection object (5) perpendicularly.

The inclined light unit 23 is disposed at the side of the horizontal light unit 22 to provide light in the oblique direction.

The central camera unit 30 is a component for photographing the inspection object 5 in a plan view, and preferably, may be provided as a charge coupled device (CCD) camera.

The grid irradiated by the grid pattern irradiation unit 50-2, 50-4, 50-6, and 50-8 while performing the two-dimensional inspection of the inspection object 5 by the central camera unit 30. By measuring the degree of deformation of the pattern can be measured the height of the inspection object.

In the case of the conventional vision inspection apparatus, a half mirror is disposed in front of the center camera unit, and reflects the light from the lighting unit, and is configured to capture an image through the camera. In the present invention, the center camera unit 30 No half mirror is placed in front.

Therefore, it is possible to capture a clearer image through the central camera unit 30.

A plurality of side camera units 40-2, 40-4, 40-6, and 40-8 are arranged symmetrically with respect to the center camera unit 30 on the side of the central camera unit 30, thereby providing an image. Eliminate blind spots and take pictures quickly.

As shown in FIG. 4, the four side camera parts 40-2, 40-4, 40-6, and 40-8 are symmetrically arranged with respect to the center camera part 30, such as a substrate. Examine the lifting and uninsertion of the parts placed on the inspection object.

The grid pattern irradiation unit (50-2, 50-4, 50-6, 50-8) is a configuration for measuring the height by irradiating the grid pattern on the inspection object 5, a liquid crystal panel or a digital micromirror display ( DMD: Digital Micromirror Display and light source.

Thus, the grid-shaped pattern is irradiated onto the inspection object 5 by the control of the control unit 70, and the degree of deformation of the grid-shaped pattern is photographed through the central camera unit 30, We can calculate the height of.

Here, the central camera unit 30 and the grid pattern irradiation unit 50-2, 50-4, 50-6, 50-8 are polarizing plates 33, 53-2, 53-4, 53-6, 53-8 Are installed respectively.

Thus, the grid pattern irradiated from the grid pattern irradiation unit 50-2, 50-4, 50-6, 50-8 is the grid pattern irradiation unit (50-2, 50-4, 50-6, 50-8) The light is irradiated through the polarizing plates 53-2, 53-4, 53-6, and 53-8 disposed in the light emitting plate, and photographed by passing through the polarizing plate 33 disposed in the central camera unit 30.

In general, when light is irradiated onto a metal surface such as a lead portion or a solder portion of a semiconductor component, light is scattered on the metal surface and the polarization direction is rotated in a direction different from the originally irradiated polarization direction.

Therefore, the intensity of the light can be adjusted by removing the reflected light having the original polarization direction and using only the light of the remaining constant polarization direction for imaging.

Accordingly, as described above, the polarizing plates are disposed in the central camera unit 30 and the grid pattern irradiation units 50-2, 50-4, 50-6, and 50-8, respectively, and the polarizing plates are disposed to be rotated 90 degrees from each other. As a result, light whose polarization direction is not rotated among the light scattered on the metal surface is filtered out, and only the remaining lights can be used for imaging.

Here, the polarizing plates 33, 53-2, 53-4, 53-6, and 53-8 are rotatable to adjust the intensity of the reflected light.

Thus, the polarizing plates 33-2 disposed on the central camera unit 30 and the polarizing plates 53-2, 53-4, which are disposed on the grid pattern irradiation units 50-2, 50-4, 50-6, 50-8, By adjusting the mutual angle between 53-6 and 53-8), the intensity of light used for imaging can be adjusted.

The grid pattern irradiation unit 50-2, 50-4, 50-6, 50-8 also has four grid pattern irradiation units 50-2, 50-4, 50-6, centered on the central camera unit 30. 50-8) are arranged symmetrically and configured to irradiate the object 5 with the grid.

Here, the grid pattern irradiation unit 50-2, 50-4, 50-6, 50-8 is configured to irradiate the grid pattern of various colors, such as red, blue.

Thus, one of the grid pattern irradiation unit (50-2, 50-4, 50-6, 50-8) of the grid pattern irradiation unit irradiates the grid pattern of a larger gap as one color, the other grid pattern irradiation unit By simultaneously irradiating smaller grids with different colors, more accurate height measurements can be made while reducing the time required for component height measurements.

For example, one of the grid pattern irradiation unit (50-2, 50-4, 50-6, 50-8) of the grid pattern irradiation unit irradiates the grid pattern of a larger gap in red, the other grid pattern The irradiation unit may irradiate the grids of smaller intervals in blue, and may irradiate the grids of larger intervals and the grids of smaller intervals.

Preferably, the arrangement angle a between the grid pattern irradiation unit 50-2, 50-4, 50-6, 50-8 and the central camera unit 30 is arranged in an angle range of 25 degrees to 45 degrees. .

When the angle (a) is smaller than 25 degrees, the degree of deformation of the grid pattern according to the height of the component is small, which may cause an error in the height calculation. When the angle (a) is larger than 45 degrees, the grid pattern irradiation unit ( 50-2, 50-4, 50-6, 50-8), the difference in the width of the grid pattern irradiated on the near and far sides is too large, which may cause errors in the height calculation.

This is because, when disposed in the angular range, when the irradiated grid pattern is photographed through the central camera unit 30, the grid pattern is properly deformed according to the height of the inspection object.

On the other hand, the vision processing unit 60 calculates the image information of the inspection object 5 obtained from the camera unit through a mathematical process such as Fourier transform (Fourier Transform), and compares with the reference value input in advance The good or bad of the object 5 is determined.

In addition, the control unit 70 is a component including a motion controller for controlling the driving and operation of the stage unit 10 and the camera unit, and may be provided to control driving of the entire vision inspection apparatus according to the present invention.

The controller 70 is responsible for physical control such as photographing position control of the vision inspection apparatus, processing of photographed images, and lighting unit control according to a system control program, as well as performing inspection task and data calculation task.

In addition, the control unit 70 is in charge of the overall control of the vision inspection device, such as output device control for outputting the work contents and inspection results to the monitor and input device control for the operator to set and input various items.

On the other hand, the light diffusion unit 25, such as a light diffusion plate is disposed in front of the illumination unit 20, so that the light from the illumination unit 20 is evenly irradiated to the entire area of the inspection object.

Thus, by reducing the difference between the dark portion and the bright portion on the inspection object (5) can take a clearer image.

The light diffusion unit 25 is configured to be bent in a side cross-section so that the light diffusion unit 25 can be disposed in front of both the horizontal light unit 22 and the inclined light unit 23.

On the other hand, at one side of the central camera unit 30 is positioned a positioning camera unit 80 for checking the position of the inspection object.

Here, the positioning lighting unit 84 and the half mirror 82 is disposed in front of the positioning camera unit 80.

Thus, compared to the case of confirming the position of the inspection object through the conventional central camera, the configuration for positioning is accommodated in the housing of the separate positioning camera unit 80, thereby reducing the housing diameter of the central camera unit 30 It can be reduced and management is easy even in case of accessory failure.

5 is a conceptual diagram showing the relationship between the period (interval) of the lattice pattern and the height of the part.

Referring to Figure 5, when describing the grid irradiation process of the vision inspection apparatus according to the present invention.

First, in FIG. 5, the straight lines connecting the points a, b, c and d conceptually show the height that can be measured by the lattice pattern having a large period.

That is, a large periodic grid has a resolution of 500 micrometers, so all heights from 0 to 500 micrometers are recognized as the same height, and another height from 500 to 1000 micrometers.

This conceptually describes the resolution when measuring the height of a part using a large periodic grid, and specific numbers may vary depending on the periodic size of the grid.

The approximate height of the component is measured using a large-gap grid pattern of red color, for example, irradiated by one of the grid pattern irradiation units 50-2, 50-4, 50-6, and 50-8. Done.

That is, when the height of the hexahedral shaped part illustrated in FIG. 5 is 1680 micrometers, the height of the part is primarily measured in the range of 1500 and 2000 micrometers through the lattice of a large period.

Then, for example, a small gap of blue color is examined to measure that the height from the d point to the R point is 180 micrometers.

Thus, the total height of the part is 1500 + 180, measured 1680 micrometers.

If the height of the part is measured by using only one lattice of the small period without the height measurement process through the lattice of the large period, the lattice pattern that matches the first lattice pattern on the left in FIG. 1 Plaid, 2-1 Plaid, 3-1 Plaid, that is, whether the plaid on the top of the part and the plaid on the bottom coincide after several cycles (lattice spacing) Cannot be judged.

Therefore, such a factor may cause an error in the height inspection, which complicates the calculation process required for the height inspection and eliminates the time required for the inspection.

In the present invention, as described above, while using a large interval plaid and a smaller resolution plaid of a higher resolution, through the large interval plaid to measure the approximate range of height, a small period plaid In this way, the height can be measured more quickly and accurately.

The large period plaid and the small period plaid are photographed by irradiating the large interval plaid and the small period plaid once, or irradiating the large interval plaid once according to the requirements of the height inspection device. Photographed by a small interval, the grid pattern may be configured to enable a more accurate height measurement by photographing while moving between the large interval grid pattern.

The larger plaid spacing is preferably comprised three to six times larger than the smaller plaid spacing.

If the lattice spacing of a large period is less than three times, the difference in measurement resolution due to the difference of the period size is not large, which is not desirable for a more accurate height measurement. The difference between the spacing and the small spacing becomes so large that it has an undesirable effect on the sharpness of the grid shape finally reflected on the inspection object.

As mentioned above, although the present invention has been described by way of limited embodiments and drawings, the technical idea of the present invention is not limited thereto, and a person having ordinary skill in the art to which the present invention pertains, Various modifications and variations may be made without departing from the scope of the appended claims.

5: inspection object 10: stage part
20: lighting unit 25: light diffusion unit
30: center camera portion 40-2 to 40-8: second camera portion
50-2 to 50-8: lattice pattern irradiation unit 60: vision processing unit

Claims (13)

A vision inspection apparatus for photographing an object to be inspected assembled or assembled in a process of assembling a part with a camera and comparing the photographed image with a preliminarily inputted object image to discriminate the good or bad of the object to be inspected,
A stage unit for fixing or transferring the inspection object to an inspection position;
An illumination unit positioned above the stage unit and providing illumination to the object to be inspected;
A central camera unit positioned at the center of the illumination unit to obtain a two-dimensional shape of an inspection object;
A side camera unit disposed in a plurality of side portions of the central camera unit;
A plurality of lattice pattern irradiation units disposed between the camera and the camera at the side of the central camera unit;
A vision processing unit which reads the image photographed by the central camera unit and determines whether the inspection object is good or bad;
And a control unit for controlling the stage unit, the grid pattern irradiating unit, and the camera unit,
The grid pattern irradiation unit and the central camera unit is provided with a polarizing plate,
The grid pattern irradiation unit is a vision inspection device using a polarizing plate and a multi-grid pattern, characterized in that configured to irradiate a grid pattern having a period of different intervals. The method of claim 1,
The grid pattern irradiator includes a liquid crystal panel or a micromirror module any one of the polarizing plate and the multi-grid pattern vision inspection device. The method of claim 1,
The grid pattern irradiator is composed of a plurality, the vision inspection device using a polarizing plate and multiple grid pattern, characterized in that configured to irradiate a grid pattern of a larger period and a grid pattern of a smaller period at the same time or sequentially. The method of claim 1,
Light diffusing unit is disposed in front of the illumination unit, the vision inspection device using a polarizing plate and a multi-grid. The method of claim 1,
The illumination unit is a vision inspection device using a polarizing plate and a multi-grid pattern, characterized in that it comprises a horizontal illumination unit for irradiating light in the vertical direction and the oblique illumination unit for irradiating light in the oblique direction. The method of claim 1,
The plurality of grid pattern irradiation unit is a vision inspection device using a polarizing plate and a multi-grid pattern, characterized in that disposed opposite to each other centered on the central camera unit. The method of claim 1,
The side camera unit is a vision inspection device using a polarizing plate and a multi-grid pattern, characterized in that the mutually arranged around the center camera unit. The method of claim 4, wherein
The lighting unit includes a horizontal lighting unit for irradiating light in a vertical downward direction and an inclined lighting unit for irradiating light in an oblique direction,
The light diffusing unit is a vision inspection device using a polarizing plate and a multi-grid pattern, characterized in that disposed in front of both the horizontal light and the oblique light. The method of claim 1,
A vision inspection apparatus using a polarizing plate and a multi-grid pattern, characterized in that the positioning camera unit for positioning the inspection object on one side of the central camera unit. The method of claim 9,
A vision inspection apparatus using a polarizing plate and a multi-grid pattern, characterized in that the positioning illumination unit and the half mirror is disposed in front of the positioning camera unit. The method of claim 1,
Vision inspection apparatus using a polarizing plate and a multi-grid pattern, characterized in that the angle between the central camera portion and the grid pattern irradiation section on the side view. The method of claim 1,
And a polarizing plate disposed in the grid pattern irradiating unit and the central camera unit, the polarizing plate being configured to be rotatable. The method of claim 1,
One grid pattern irradiation unit of the grid pattern irradiation unit irradiates the grid pattern of a large period with one predetermined color, the other grid pattern irradiation unit is configured to irradiate the grid pattern of a small period with another predetermined color Vision inspection device using a polarizing plate and a multi-grid pattern.

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