KR102053103B1 - Camera assembly for line scan - Google Patents

Abstract

The present invention relates to a camera assembly for line scan, the camera provided for vision inspection of the inspection object; And a plurality of fixed reflectors provided in front of the camera to reflect the entire form of the inspection object one or more times to be transmitted to the camera, wherein the camera reflects the fixed reflector a plurality of times. By photographing the entire shape of the camera, the working distance between the camera and the inspection object is refracted a plurality of times, so that the inspection object is at the viewing angle of the camera while the actual distance of the camera and the inspection object is formed smaller than the working distance. It is located in the field of view, and provides a technology that can reduce the working distance required to secure the viewing angle of the inspection object in a limited space.
According to the present invention, by photographing a plurality of inspection objects reflected by a pair of reflectors facing the camera, the actual distance with the inspection object is formed smaller than the working distance, so that the vision inspection of a large area inspection object can be performed even in a limited space. By refraction of the working distance and the reflection of visible light to determine the presence or absence of moisture on the surface of the inspection object, the problem of edge distortion compared to the camera assembly for line scanning using a conventional high magnification camera lens or an infrared camera Of course, the cost problem can be solved.

Description

Camera assembly for line scan {CAMERA ASSEMBLY FOR LINE SCAN}

The present invention relates to a camera assembly for line scan.

In general, the manufacturing process for making large-area thin glass substrates such as LCDs and OLEDs consists of evaporation, coating, development, exposure, and cleaning processes of many thin films. .

Among them, the cleaning process is a process for washing stains or various foreign matters that may occur on the glass surface in a coating process for improving the surface properties of the glass, photoresist, and etching, and a wet cleaning method is widely used.

The wet cleaning method is easy to rinse with DI (Deionized) Water, very little residue after drying, and it is possible to use many kinds of chemical solutions according to the contaminants to be removed, and it is very effective and reliable and reproducible. Although widely used for its advantages, it is possible to recontaminate contaminants from the chemical solution to the substrate using solutions such as strong bases and strong acids.

In addition, the most fundamental problem of the wet cleaning method is that the wet cleaning is an ex-situ cleaning process, which is inevitably exposed to the air when moving to the process equipment after cleaning, which is likely to be contaminated by impurities such as organic pollutants or particles. Is the point.

Therefore, after the wet cleaning process is finished, it is preferable to remove water using an air knife from the DI water washed out of the cleaning solution, and then allow the next process to proceed in a dried state.

`` Korean Patent Publication No. 10-2015-0054517, Name of the Invention: Surface Inspection Method and Inspection Device of Display Panel, (Published Date: May 20, 2011, Applicant: Intek Plus Co., Ltd.) The technical configuration of the method and apparatus for determining the type of defects on the surface of the display panel by comparing the intensity distribution of the reflection images obtained by reflecting light of different incidence angles irradiated from a plurality of light sources on the surface Is disclosed.

After the general wet cleaning process, the method of determining the presence or absence of moisture on the surface of the glass is also determined by the presence or absence of moisture on the surface through the difference in light or illuminance reflected according to the amount of moisture on the surface of the glass, as described above. Determine.

However, as the size of the glass, that is, the size of the inspection object increases, in order to secure a viewing angle for vision inspection, a working distance must be secured accordingly, but it is difficult due to limitations in the installation space.

Therefore, a method using a high magnification lens such as a fisheye lens or a wide-angle lens has been proposed, but a lens cost is high and images captured with a high magnification lens of 0.04 or more magnification are obtained with a distorted edge, making it difficult to guarantee the reliability of the image. There is.

In addition, in general, infrared cameras have been used as a vision sensor for measuring the moisture on the glass surface, but it is not only expensive but also difficult to photograph a large-area inspection object.

Patent Document (0001) `` Korean Patent Publication No. 10-2016-0101317, Name of the Invention: Surface Inspection Apparatus, (Published: August 25, 2016, Applicant: Samsung Electronics Co., Ltd.) ''

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object thereof is to provide a technology capable of reducing a working distance required to secure a viewing angle of an inspection object in a limited space.

The problem to be solved by the present invention is not limited to the above-described problem, other technical problems that are not mentioned will be clearly understood by those skilled in the art from the following description.

In one aspect of the present invention, a camera provided for vision inspection of the inspection object to achieve this object; And a plurality of fixed reflectors provided in front of the camera to reflect the entire form of the inspection object one or more times to be transmitted to the camera, wherein the camera reflects the fixed reflector to the whole of the inspection object. By photographing the shape, the working distance between the camera and the inspection object is deflected a plurality of times, so that the inspection object is the camera while the actual distance of the camera and the inspection object is smaller than the working distance. To be located within the field of view.

The fixed reflector may include: a first reflector configured to initially reflect the shape of the inspection object; And a second reflector installed to face the first reflector to reflect the shape of the test object reflected by the first reflector again, wherein the second reflector is reflected by the first reflector. By reflecting the shape of the object back to the first reflector, the shape of the test object is reflected to the first reflector at least twice or more times so that the working distance is refracted by a plurality of opposing pairs of reflectors. Can be.

In addition, the camera, the photographing angle for photographing the inspection object is adjusted, the incident angle of the form of the inspection object reflected to the fixed reflector may be adjusted.

The fixed reflector may be provided in a pair in which the first reflector and the second reflector are parallel to each other, and may be provided in a planar shape so that the shape of the inspection object is reflected at a 1: 1 magnification.

In addition, the reflection angle is provided to be adjusted to finely adjust the incident angle and the viewing angle of the test object to be reflected, and an adjustable reflector to reflect the shape of the test object to be reflected to the second reflector in place of the first reflector; It may include.

And an illuminator for irradiating light at the same incident angle symmetrically with the incident angle that the form of the inspected object is incident on the fixed reflector, based on a direction perpendicular to the plane on which the inspected object is placed. The light emitted from the illuminator is diffusely reflected by the moisture present on the surface of the inspection object, and the presence or absence of moisture present in the inspection object can be determined based on the difference in the shade of the image photographed by the camera. The illumination unit may be provided with a rotation axis of the illumination unit to rotate the irradiation direction of light.

Means for solving the above problems are merely exemplary and should not be construed as limiting the present invention. In addition to the exemplary embodiments described above, there may be additional embodiments described in the drawings and detailed description of the invention.

As described above, the present invention has the following effects.

First, by photographing a plurality of inspection objects reflected by a pair of reflectors facing the camera, the actual distance to the inspection object is formed smaller than the working distance, it is possible to perform a vision inspection of the inspection object of a large area in a limited space.

Second, by refraction of the working distance and the reflection of visible light to determine the presence or absence of moisture on the surface of the test object, the edge distortion is not only compared to the line assembly of the camera assembly used for the high magnification camera lens or the infrared camera. This solves the cost problem.

Third, measure the moisture on the surface of the inspection object by using diffuse reflection of light emitted from the illuminator, and visualize the range of the measured moisture, as well as correction work that reflects the area, reflection brightness, and degree of aggregation of moisture. Through this there is an advantage that can estimate the time of complete evaporation of water.

The effects of the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

1 is a block diagram showing a basic configuration of a camera assembly for a line scan according to an embodiment of the present invention.
2 is a diagram illustrating a configuration of a line scan camera assembly in which an adjustable reflector according to another embodiment of the present invention is provided at another position.
3 is a view illustrating a principle of securing a viewing angle by using an image repeatedly reflected to a fixed reflector according to an exemplary embodiment of the present invention.
4 is a view showing a principle of determining the presence or absence of water on the surface of the inspection object by using light of the illuminator according to an embodiment of the present invention.
FIG. 5 is a diagram illustrating a configuration of a line scan camera assembly in which fixed reflectors according to another embodiment of the present invention are disposed in parallel with the conveying direction or rotated in an oblique form.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings, and the well-known technical parts will be omitted or compressed for brevity of description.

1 is a block diagram showing a basic configuration of a line scan camera assembly according to an embodiment of the present invention, Figure 2 is a line scan camera assembly in which the adjustment reflector according to another embodiment of the present invention is provided in a different position It is a figure which shows a structure.

The line scan camera assembly CA of the present invention scans the inspection object IO to determine the presence or absence of surface defects or foreign matter on the inspection object IO, and the viewing angle of the inspection object IO of a large area is determined. By refracting the working distance necessary to secure a plurality of times to be stacked, it is possible to overcome the spatial constraints by reducing the actual distance (camera 100) for the vision inspection and the inspection object (IO).

As shown in FIG. 1, the line scan camera assembly CA of the present invention includes a camera 100, a fixed reflector 200, an adjustable reflector 300, and an illuminator 400 to perform the above-described functions. Includes the configuration of.

The camera 100 is installed on an upper portion of the conveyor system for transporting the inspection object IO to obtain an image of the inspection object IO. Image acquisition methods are divided into area cameras and line scan cameras according to the type of camera, which is an image acquisition device. Due to problems such as a decrease in inspection speed, an embodiment of the present invention assumes a line scan camera having high resolution, high image acquisition speed, low noise, uniform image acquisition, and infinite length image acquisition function and advantages. do.

Here, the photographing direction of the camera 100 of the present invention is not provided to face the conveyor line to which the inspection object (IO) is transferred, but is installed to face the reflector to secure the working distance, the photographing angle can be adjusted It is provided to be tilted based on the camera rotation axis (not shown).

In addition, a tilting reflector 110 may be provided between the camera 100 and the fixed reflector 200 to perform a separate rotation operation instead of the tilting function of the camera 100. (See FIG. 2). The camera 100 may be provided with a fixed shooting direction, and a tilting reflector 110 that may rotate in the shooting direction of the camera 100 may be provided to perform a tilting function of the camera 100 instead.

Referring back to FIG. 1, the fixed reflector 200 is provided as a pair of opposite mirrors standing up in a direction perpendicular to the transport direction of the inspection object IO, and reflects the shape of the inspection object IO a plurality of times. By being transmitted to the 100, the above-mentioned operating distance is to be formed in a refracted state, that is, zigzag between a pair of mirrors, so that the field of view according to the operating distance refracted and accumulated in the camera 100 is To be secured.

The fixed reflector 200 includes a first reflector 210 that initially reflects the shape of the inspection object IO and an inspection to be parallel to the first reflector 210 and reflected on the first reflector 210. The configuration of the second reflector 220 reflects the shape of the object IO back to the camera 100 or reflects back to the first reflector 210. In this case, the first reflector 210 and the second reflector 220 are only distinguished names given for convenience of description, and the second reflector 220 may also reflect the form of the inspection object IO for the first time. The reflector that finally delivers the image of the inspection object IO to the camera 100 may also be the first reflector 210 or the second reflector 220.

The adjustable reflector 300 is provided below the first reflector 210 that initially reflects the shape of the inspection object IO described above, that is, the control reflector 300 is the first reflector 210 and the inspection object IO. It is provided between and reflects the shape of the inspection object (IO) to the second reflector 220 in place of the first reflector 210, is rotated based on the rotation axis of the control reflector to fine-tune the working distance, the final viewing angle By adjusting, the entire external shape of the inspection object IO is completely transmitted to the camera 100 through the fixed reflector 200.

The illuminator 400 is provided between the second reflector 220 and the inspection object IO, and the light reflected by irradiating light onto the surface of the inspection object IO is reflected by the first reflector 210 or the control reflector. In order to reach 300, the light is reflected so that the light reflected by the glass coincides with the angle incident on the first reflector 210 or the control reflector 300 based on a direction perpendicular to the transport direction. The angle is determined.

To this end, the illuminator 400 is provided with a rotating axis of illumination (not shown) to rotate the irradiation direction of light, and the illuminator moving part (not shown) is provided to illuminate the illuminator 400 as an inspection object ( Of course, it can be reciprocated before and after the transfer direction of the IO).

3 is a view illustrating a principle of securing a viewing angle by using an image repeatedly reflected to a fixed reflector according to an embodiment of the present invention, and FIG. 4 illustrates light of an illuminator according to an embodiment of the present invention. It is a figure which shows the principle which determines the presence or absence of water | moisture content on the surface of a test object by using.

As shown in FIG. 3, the line scan camera assembly CA of the present invention includes the entirety of the inspection object IO reflected through the pair of fixed reflectors 200 facing the camera 100 side by side. By photographing the shape, it is possible to overcome the space constraint and measure the presence or absence of moisture on the glass surface of the large area.

Specifically, in order to photograph the glass surface of the large area, the operating distance WD of the camera 100 proportional to the viewing angle of the inspection object IO is required (see FIG. 3A), that is, the entire inspection object IO. As the size of the shape increases, the camera 100 also needs a larger working distance, so the line scanning camera 100 has to be installed at such a high position from the conveyor transfer line. Since the permissible height is determined, the line scanning camera 100 having a straight working distance is subject to the limitation of installation.

Thus, by providing a pair of reflectors, that is, a mirror to convert the operating distance of the straight line from the camera 100 to the inspection object (IO) to the sum of the refracted operating distances reflected on the mirror, thereby making the existing operating distance the same While maintaining the same viewing angle to secure the same, the actual distance between the camera 100 and the inspection object (IO) can be greatly reduced (see FIG. 3b).

In more detail, the process of securing a viewing angle using a pair of reflectors requires the operating distance that is required to obtain a wider viewing angle, and thus the sum of the operating distances refracted by the larger number of reflection processes. Should be increased.

To this end, the photographing direction of the camera 100 is tilted so as to be close to the vertical direction of the reflector plane, and in order to reduce the sum of the refracted operating distances in order to narrow the viewing angle and increase the resolution accordingly, the photographing direction of the camera 100. Should be tilted from the vertical to the horizontal direction of the reflector plane.

In addition, the shape of the inspection object (IO) that is reflected on the pair of reflectors may show a large difference even in the change of the minute tilting angle of the camera 100, the lower portion of the first reflector 210, the control reflector 300 As well as fine operating distance adjustment, the direction and size of the viewing angle toward the inspection object (IO) can be adjusted.

In addition, while photographing a large area of the inspection object (IO) through a process of securing a wider viewing angle with the sum of the above-described refractive operating distances, the shape of the inspection object (IO) is vertically adjusted through the adjustment reflector (300). By photographing diagonally rather than in one direction, a larger area can be photographed.

On the other hand, when the entire shape of the inspection object (IO) is photographed by the camera 100 on the principle described above, the light irradiated from the illuminator 400 is reflected on the inspection object (IO) to be photographed by the camera 100 Thereby, the surface foreign matter of the test object IO can be determined by the difference of the shadow.

Referring to FIG. 4, when the foreign matter determination process on the surface of the inspection object IO is described, the light irradiated onto the glass surface of the inspection object IO is reflected in the same incident angle and reflection angle (FIG. 4A). When water droplets remain on the glass surface, the incident light is refracted and reflected by the refractive index of the water droplet (FIG. 4B). In this case, the glass should be made of a material that reflects light. to be.

Therefore, when the amount of moisture of DI water for removing the cleaning liquid on the glass surface is small, the amount of reflected light is large and many parts appear bright (FIG. 4C). When the amount of moisture is large, the reflected light is applied to the reflected light. In comparison, the amount of light that is refracted is relatively greater, so that the darker portion is photographed more (FIG. 4D).

Furthermore, through such a difference in shadow, it is possible to estimate the complete evaporation time of the measured residual moisture according to the amount of moisture and the density of moisture as well as the presence or absence of moisture remaining on the glass surface as the inspection object (IO). Of course.

FIG. 5 is a view illustrating a configuration of a line scan camera assembly in which fixed reflectors are disposed in parallel with each other in a transport direction or rotated in a diagonal form according to another embodiment of the present invention.

As shown in FIG. 5, in the line scan camera assembly CA of another embodiment of the present invention, the fixed reflector 200, which is provided as a pair of mirrors, is installed in a direction parallel to the transport direction of the inspection object IO. The amount of moisture remaining on the surface of the test object (IO) can be measured.

The line scan system of the present invention inspects a large-area inspection object (IO) by securing an appropriate viewing angle according to an operating distance based on an image of the inspection object (IO) reflected a plurality of times in a limited space. It will also be included in the technical idea of the present invention that the process is formed in a horizontal direction, a vertical direction or an oblique direction in the transport direction of the inspection object (IO).

Specifically, when the fixed reflector 200 is installed in the direction parallel to the conveying direction of the inspection object IO, the limitation of the inspection space for the line scan is as much as the distance between the first reflector 210 and the second reflector 220. Since the length is formed by the height of, and the length can be formed along the conveying direction of the conveyor system, the constraint of the space can be greatly reduced.

In addition, when the fixed reflector 200 is installed in the direction parallel to the conveying direction, unlike when the fixed reflector 200 is installed in the vertical direction, the adjustable reflector 300 can be installed above the line scan inspection space. In addition, by increasing the photographing angle of the inspection object (IO) includes the effect of more accurately measuring the image taken without distortion.

In addition, in the camera assembly CA for a line scan according to another embodiment of the present invention, the fixed reflector 200 formed of the first reflector 210 and the second reflector 220 rotates, respectively, so that the first reflector 210 is rotated. And the angle formed by the second reflector 220 may not be parallel to each other, or may be arranged in a form parallel to the conveying direction or in an oblique form.

Specifically, by opening or narrowing in the longitudinal direction of the two reflectors 210 and 220 according to the purpose, to adjust the photographing angle of the inspection object (IO) without the configuration of the control reflector 300, or to limit the space to be installed In order to overcome, the fixed reflector 200 may be installed in a horizontal direction or a vertical direction with respect to the conveying direction, and sometimes may be installed in a diagonal form. When installed in an oblique form, the photographing angle of the inspection object (IO) may be close to the direction perpendicular to the upper part of the conveyor, and thus, even if the fixed reflector 200 is not required without a separate control reflector 300, the inspection object (IO) ) Can be measured closer to the front.

As described above, the detailed description of the present invention has been made by the embodiments with reference to the accompanying drawings. However, since the above-described embodiments have only been described with reference to preferred examples of the present invention, the present invention is limited to the above embodiments. It should not be understood that the scope of the present invention is to be understood by the claims and equivalent concepts described below.

CA: Camera Assembly for Line Scan
100: camera
110: tilting reflector
200: fixed reflector
210: first reflector
220: second reflector
300: adjustable reflector
400 illuminator
IO: Inspection object

Claims (7)

A camera provided for vision inspection of the inspection object; And
And a plurality of fixed reflectors provided in front of the camera to reflect the entire form of the inspection object one or more times to be transmitted to the camera.
The camera reflects the fixed reflector and photographs the entire shape of the inspection object, such that a working distance between the camera and the inspection object is deflected a plurality of times, thereby causing an actual distance of the camera and the inspection object. Is formed to be smaller than the working distance so that the inspection object is located within the field of view of the camera,
The fixed reflector,
A first reflector for initially reflecting the shape of the inspection object; And
A second reflector installed to face the first reflector to reflect the shape of the test object reflected by the first reflector again;
The second reflector reflects the shape of the test object reflected by the first reflector back to the first reflector, such that the shape of the test object is reflected at least twice or more times in the first reflector, facing each other. Through a pair of reflectors to see the working distance is bent a plurality of,
And a control reflector configured to adjust a reflection angle to finely adjust an incident angle and a viewing angle of the inspected object to be reflected and reflect the shape of the inspected object to be reflected on the second reflector in place of the first reflector. ,
The control reflector is provided between any one of the first reflector or the second reflector and the inspection object,
And an illuminator for irradiating light at an incident angle symmetrically with an incident angle incident on the fixed reflector in the form of the inspected object, based on a direction perpendicular to a surface on which the inspected object is placed.
The light irradiated from the illuminator is diffusely reflected by the moisture present on the surface of the inspection object, and the presence or absence of moisture present in the inspection object is determined by the shade difference of the image photographed by the camera. doing
Camera assembly for line scan. delete The method of claim 1,
The camera,
The photographing angle for photographing the inspection object is adjusted, so that the incident angle of the inspection object shape reflected by the fixed reflector is adjusted.
Camera assembly for line scan. The method of claim 1,
The fixed reflector,
The first reflector and the second reflector are installed in a pair parallel to each other, each provided in a planar shape so that the shape of the inspection object is reflected at a 1: 1 magnification.
Camera assembly for line scan. delete delete The method of claim 1,
The illuminator is provided with a rotation axis of the illuminator to rotate the irradiation direction of the light, characterized in that
Camera assembly for line scan.

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