KR101192331B1 - Vision inspection equipment and inspection methods of lens by using area camera - Google Patents

Abstract

PURPOSE: A device and a method for testing the lens vision using an area camera are provided to accurately and rapidly test various faulty elements of a lens, thereby enhancing the reliability of a test. CONSTITUTION: A device for testing the lens vision using an area camera comprises an area camera(100), a tray member(200), an upper lighting unit(400), and a lower lighting unit(500). The height of the area camera is regulated so that a focus is adjusted according to a shape change of a lens. A plurality of through-holes is formed on a surface of the tray member. A hanging member is comprised in the inner circumference of the through-hole so that the lens is hung by the hanging member and loaded. A penetrated hole which diameter becomes larger toward to a lower part from an upper part is formed in the central part of the upper lighting unit so that an inclined part is formed in the inner circumference of the penetrated hole and a plurality of LEDs is formed in the inclined part. A plurality of the LEDs is installed in an upper accommodation unit of the lower lighting unit.

Description

Vision inspection equipment and inspection methods of lens by using area camera}

The present invention relates to a vision inspection device for inspecting the abnormality of the lens by using an area camera and a method for inspecting the same, and more particularly, to improve the reliability of defect inspection of lenses having various shapes and to increase the efficiency of inspection work. A vision inspection apparatus and inspection method for a lens using an area camera.

In general, in determining the abnormality of the product, when the worker visually inspects, real-time inspection and full inspection are difficult, the inspection speed is low, and the reliability of the inspection result is likely to be deteriorated depending on the skill and fatigue of the worker. It is difficult to secure image results and statistical data to reflect in the process.

Therefore, by using vision inspection device as an alternative to solve this problem, quality competitiveness can be secured through efficient quality control, reliability and inspection efficiency can be improved by automating inspection process, and defect images and data of products are collected. It is possible to make effective quality control by making a database, and to use the high-performance hardware and the algorithm according to it, it is possible to make uniform inspection irrespective of external factors (worker fatigue, individual difference), and to make quick and accurate full inspection.

Such vision inspection apparatus is mainly used in various manufacturing processes such as surface finish inspection of products, physical defect tracking, inspection of textile products, color inspection, and inspection of semiconductor manufacturing process. , A frame grabber for processing an image, a computer and an algorithm for analyzing and determining the obtained image, and an ejector for extracting a defective product according to the determination.

On the other hand, the type of camera used in such a vision inspection device is largely a line scan camera (area scan camera) and an area camera (area camera), the area camera is the biggest feature is to scan and transmit only one frame at a time, Shooting is possible only when the subject and the camera are stationary.

On the other hand, the line scan camera has a sensor composed of pixels only horizontally and only one line vertically so that the object can be photographed while the object and the camera are moving.

Therefore, in order to use a line scan camera, the camera's shutter speed, the inspection object, and the moving speed of the camera must be accurate to obtain an accurate image, and the resolution of the camera must be high.

In addition, the prior art of the vision inspection device as described above, such as domestic published patent 2012-0033071 "vision inspection lighting device" or domestic patent registration No. 593992 "vision inspection device" or domestic published patent 2010-0129846 "vision inspection device Has already been proposed.

On the other hand, in the case of inspecting the lens applied to the camera using the vision inspection device as described above, the inspection items are inspected for the presence of fingerprints, foreign substances, black spots, white spots, scratches and the like.

However, when the lens is a product having a curved surface of various forms, the camera used in the vision inspection apparatus should be able to change the focus along the curved surface of the lens.

However, in the conventional area camera or line scan camera, it is difficult to match the inspection angle of view and the illumination source angle according to the thickness and curvature of the lens.

In addition, fingerprints, foreign objects, white spots, black spots, scratches, etc., which are defects of the lens, may or may not be found depending on the viewing angle, so that a camera that shoots vertically and a camera that shoots obliquely are installed successively. A separate lighting unit for illuminating the lens in the vertical direction and the inclined direction was identified to identify the defective element of the lens.

In other words, two or more cameras are required to check for defects by checking for black spots or white spots through a camera photographed vertically, and checking for debris and scratches through a camera installed and photographed to have an inclination angle. There was a problem that was not easy in terms of cost and maintenance due to size and fabrication.

Therefore, the present invention has been made to solve the above-described problems, and accurately and quickly to correct the defects of the lens through the area camera that the focus is adjusted along the curved surface of the lens and the illumination unit which is simultaneously illuminated from the upper and lower sides of the lens. It is related to the vision inspection apparatus and inspection method of the lens using an area camera, which can improve the precision and efficiency of the inspection work by allowing the inspection to be carried out easily.

According to a preferred embodiment of the present invention,

An area camera whose height is adjusted in the vertical direction to adjust the focus according to the shape change of the lens;

A tray member having a plurality of through holes penetrating the upper and lower surfaces thereof, and a locking means provided at an inner circumferential surface of the through hole, the lens having the lens hooked on the locking means;

It is installed between the area camera and the tray member, the through-hole is formed in the center to increase in diameter from the upper side to the lower side so that the inclined portion is formed on the inner circumferential surface of the hole, the plurality of LEDs are installed in the inclined portion An upper illumination unit for allowing the light source to be inclinedly irradiated on the upper surface of the tray member; And

The lower portion of the tray member is provided at regular intervals, and is associated with a lower lighting unit in which a plurality of LEDs are installed in the upper receiving portion.

Preferably, the LED installed in the inclined portion of the upper lighting unit is associated with being installed to allow the angle adjustment manually or automatically.

More preferably, the LEDs installed in the inclined portion of the upper lighting portion are arranged in a single row or in a plurality of rows along the inclined portion.

More preferably, the lower illumination part is related to the installation of a diffuser plate on top of the LED so that the illumination of the LED can be illuminated entirely on the tray member.

More preferably, the locking means may be configured such that the diameter of the through hole becomes smaller from the upper side to the lower side so that the outer edge of the lens fitted from the upper side of the through hole is caught and fixed between the upper side and the lower side of the inner circumferential surface of the through hole. It is related to one.

More preferably, the locking means is formed by forming a locking jaw on the inner circumferential surface of the through hole so that the outer edge of the lens can be seated and fixed to the locking jaw.

According to an exemplary embodiment of the present invention, a product loading process of loading a plurality of lenses to be inspected in the tray member and then being transported by a conveyor to be stopped in the vision inspection waiting section;

A product cleaning process in which air is sprayed onto the lens of the tray member which is stopped in the vision inspection waiting section to clean the lens;

After the lens cleaning process is completed, the light is irradiated from the upper and lower lighting units installed in the vision inspection section while the lens is moved to the vision inspection section, and the area camera moves up and down along the curved surface of the lens to focus the lens. While taking three shots per lens, the upper surface of the tray member is moved in the zigzag direction, and the lenses loaded in the tray member are sequentially photographed one by one. The photographed images are transferred to a computer, and the algorithm is analyzed and judged. Product inspection process;

A defective product marking process for indicating that the defective lens is found in the product inspection process;

And a product unloading process in which a lens marked as defective by a defective product marking process is removed by an operator.

In the vision inspection apparatus according to the present invention, when inspecting a defect of a lens having a variety of curved surfaces, the various defects of the lens through the area camera that is moved up and down along the curved surface and an illumination unit which is simultaneously illuminated from the upper and lower sides of the lens. It is possible to inspect accurately and quickly, which improves the reliability of defect inspection, improves the efficiency of inspection work, and makes lens quality control more effective.

1 is a perspective view illustrating main parts of a vision inspection apparatus according to an exemplary embodiment.
Figure 2 is a perspective view illustrating a tray member used in the vision inspection apparatus according to an embodiment of the present invention.
3A is a cross-sectional view of a tray member according to an embodiment of the present invention.
3B is a cross-sectional view of the tray member according to another embodiment of the present invention.
4 is a perspective view illustrating the upper lighting unit used in the vision inspection apparatus according to an embodiment of the present invention.
5 is a flowchart illustrating a vision inspection method according to an embodiment of the present invention.

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

This is for the purpose of describing the present invention in detail so that those skilled in the art can easily practice the present invention, and thus, the technical spirit and scope of the present invention are not limited thereto.

In addition, the sizes and shapes of the components shown in the drawings may be exaggerated for clarity and convenience of explanation, and the terms defined specifically in consideration of the configuration and operation of the present invention may vary depending on the intention or custom of the user, operator And the definitions of these terms should be based on the contents throughout this specification.

First, FIG. 1 is a perspective view illustrating main parts of a vision inspection apparatus according to an exemplary embodiment of the present invention. The vision inspection apparatus according to the present invention includes an area camera 100 that photographs a lens 300 and a plurality of lenses ( The tray member 200 on which the 300 is loaded, the upper lighting unit 400 that assists the photographing of the lens 300, and the lower lighting unit 500 are divided into the tray members 200, but are not shown in the drawing. Algorithm for receiving and analyzing the captured image, the analysis, and the like, a computer for performing this, various sensors, the transfer means of the tray member 200 and the like.

In this configuration, the area camera 100 is a device for photographing the lens 300, and is composed of a 5 megapixel class of 1x macro lens. In this case, the thickness of the lens 300 to be inspected depends on its shape. Since the curvature is different, the focus thereof is not constant. Therefore, the area camera 100 is configured to be adjusted in the Z axis, that is, the vertical direction as a means for accurately adjusting the focus.

Here, the vertical direction adjusting means of the area camera 100 may be manually operated by the operator, but it is preferable that the area camera 100 can be automatically adjusted by a precision robot for precision.

In addition, as described above, although the vertical movement of the area camera 100 may be focused using a precision robot, the focus may vary depending on the thickness and curvature of the lens 300, but the area camera 100 may be configured in an optical multi-focus method to focus. You can also adjust the focus by configuring the MEMS (Micro Electro Mechanical Systems) variable focus.

In addition, the tray member 200 for loading the lens 300 to be inspected has a plurality of through holes 210 formed at regular intervals on a rectangular flat plate, as illustrated in FIG. 2, to the through holes 210. The lens 300 is configured to be fixed while being fitted.

Here, the shape of the tray member 200 need not be limited to a square, and may be configured in various shapes in consideration of the efficiency of the circular or non-circular or inspection as necessary.

In addition, in the lens 300 being loaded in the through hole 210 of the tray member 200, the lens 300 is correctly loaded, and it is necessary to prevent the lens 300 from flowing after being loaded. It is provided with a locking means, so that the lens 300 to be loaded in the through hole 210 is caught by the locking means of the through hole 210 so that the lens 300 in the through hole 210 can be loaded accurately and without flow. It is.

Here, as an example of the locking means to form a through hole 210 in the tray member 200, as shown in Figure 3a, the diameter is configured to gradually decrease from the upper side to the lower side, the upper side of the through hole 210 The diameter is larger than the diameter of the lens 300 to be loaded, and the lower diameter of the through hole 210 is smaller than the diameter of the lens 300 to be loaded, so that the lens 300 penetrates the tray member 200. At the entrance of the ball 210, it is easily fitted, and when it is inserted down to the lower side, the outer circumference of the lens 300 is inserted into the outer circumferential surface of the through hole 210 at the middle of the through hole 210 so as to be fitted and fixed. .

Therefore, the operation of fitting the lens 300 to the through hole 210 of the tray member 200 becomes easy, and after the lens is naturally fixed to the through hole 210, the plurality of lenses 300 are fixed. Is to be fixed to the through hole 210 to the same depth.

In addition, as another embodiment of the present invention, when the lens 300 is fitted into the through hole 210 of the tray member 200 and the outer circumference of the lens 300 is fixed to the lower inner peripheral surface is fixed to the through hole 300 Since it can be fitted in an inclined state to the 210 to form a locking jaw 211 protruding along the inner circumferential surface of the through-hole 210 in order to prevent this, but may be configured as a body, the locking jaw ( 211) may be composed of a plurality of bodies and arranged radially.

Accordingly, the lens 300 inserted into the through hole 210 moves downward of the through hole 210, and the outer side of the lens 300 is seated on the locking jaw 211, and the lens 300 passes through the 210. ) Can be loaded horizontally without tilting to the correct position.

At this time, the through-hole 210 is configured as the engaging jaw 211 on the inner circumferential surface of the through-hole 210 in the state configured to decrease in diameter from the upper side to the lower side as illustrated in Figure 3b, through-hole 210 It is also desirable to allow the lens 300 to be loaded accurately) and to be loaded without flow.

On the other hand, the upper lighting unit 400 and the lower lighting unit 500 is configured as the lighting means for photographing the lens 300 with the area camera 100, the upper lighting unit 400 and the area camera 100 as shown in FIG. Located between the tray member 200, the through hole 410 is formed in the center is formed in a ring shape having a constant thickness.

In addition, the hole 410 is configured so that the diameter is gradually increased from the upper side to the lower side to be formed in the inclined portion 411 on the inner peripheral surface of the hole 410, the inclined portion 411 a plurality of LEDs 600 ) Is installed.

Here, the LED 600 is installed in the vertical direction to the inclined portion 411 so that the light source irradiated from the LED 600 is irradiated in the vertical direction from the inclined portion 411, the irradiation of the LED 600 The angle of the light source may be configured to be irradiated in the vertical direction from the inclined portion 411, but may be configured so that the irradiated angle can be adjusted according to the shape of the lens 300.

To this end, the angle of the LED 600 installed on the inclined portion 411 may be manually adjusted by the operator, but can also be automatically adjusted using a control system, and the LED 600 on the inclined portion 411 as an angle adjusting means. It is also desirable to combine the back portion of the) in a universal joint method to be able to vary the irradiation angle of the LED 600 with respect to the inclined portion 411.

In this case, the angle adjustment of the LED 600 may select some of the plurality of LEDs 600 according to the shape of the lens 300 to individually adjust the angles, and the plurality of LEDs 600 by means of a link or the like. You can also adjust the angle at the same time.

In addition, the LED 600 installed in the inclined portion 411 may be arranged in a single row on the inclined portion 411, but may also be configured in a plurality of rows, which is composed of a plurality of rows of the LED 600 LED 600 The irradiation angle of is to be changed according to each column, thereby to find a wider range of defects that can be found in the lens 300.

In addition, the lower lighting unit 500 has an accommodating part 510 formed at an upper side thereof, and a plurality of LEDs 600 are installed at the accommodating part 510 so that the lens 300 loaded on the tray member 200 is upper part from the lower part. In order to illuminate the light, and to install a diffuser plate (not shown in the drawing) at a predetermined distance on the upper side of the lower lighting unit 500 as necessary, when shooting by the area camera 100 through the distribution of lighting It may be possible to identify the elements more effectively.

Wherein the light emitting diode (LED) 600 is a light emitting diode, the light source of the upper lighting unit 400 and the lower lighting unit 500 need not be limited to the LED 600 as described above, the area camera 100 If it is a light source for identifying the defective element of the lens 300 to be photographed by any one can be replaced.

In addition, the lower lighting unit 500 may be used in place of the upper lighting unit 400.

The inspection process of the vision inspection apparatus including the area camera 100, the tray member 200 on which the lens 300 is loaded, the upper lighting unit 400, and the lower lighting unit 500 will be described with reference to FIG. 5. As follows.

That is, first, a plurality of lenses 300 to be inspected in the tray member 200 is loaded, then conveyed by the conveyor 700 and the product loading process S1 stopped in the vision inspection waiting section is performed. The product cleaning process (S2) is performed by spraying air and cleaning the lens 300 of the tray member 200 which is stopped in the vision inspection waiting section.

Here, in the case of the conveyor 700, since the illumination should be irradiated up and down of the tray member 200 which is mounted on the conveyor 700 and moved, the installation hole 710 through which the upper and lower portions are penetrated to the tray member 200. ) Is formed and mounted on the tray member 200 in the installation hole 710 to be fixed so that the illumination of the upper lighting unit 400 and the lower lighting unit 500 above and below the tray member 200 can be irradiated.

After the product cleaning process (S2) is finished, the lens 300 is moved to the vision inspection section and receives the illumination of the upper lighting unit 400 and the lower lighting unit 500 while the area camera 100 is loaded on the tray member 200. Product inspection process (S3) for photographing the lens 300 is performed.

In this case, the area camera 100 is generally taken three times while being precisely moved up and down along the curved surface of the lens 300 to be loaded. In this case, the number of shots need not be limited to three times. It can be taken with 3 to 3 shots or more.

The lens 300 moves the upper surface of the tray member 200 in a zigzag direction to sequentially photograph the lenses 300 loaded on the tray member 200 one by one, and the photographed images are transmitted to a computer to generate an algorithm. To be analyzed and judged.

Here, if the lens 300 has a fingerprint, a foreign material or a scratch, it can be photographed by the area camera 100 with the help of the upper lighting unit 400, and if the lens 300 has a black spot or a white spot, the lower lighting unit With the help of 500 it can be taken by the area camera 100.

Therefore, due to the upper lighting unit 400 and the lower lighting unit 500, fingerprints, foreign substances, scratches, black spots, or white spots, which are defective elements of the lens 300, may be simultaneously detected by photographing the area camera 100. The defective element is analyzed and judged by a computer.

The lens 300, which has been inspected through the product inspection process (S3) as described above, moves to the defective product marking process (S4) and is marked to indicate that the lens 300 in which the defective element is found is defective, and the lens indicated as defective ( 300 is to be removed by the worker through the product unloading process (S5).

As described above, in the present invention, when inspecting a defect of the lens 300 having various curved surfaces, the upper and lower sides of the area camera 100 and the lens 300 which are moved up and down along the curved surface are irradiated. Through the upper lighting unit 400 and the lower lighting unit 500 can be inspected a variety of defects in one shot to improve the workability and precision of the inspection, it is possible to further double the vision inspection efficiency through a quick inspection work. .

Although the present invention has been described in connection with certain exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. Therefore, the scope of the present invention should not be limited by the described embodiments, but should be defined by the appended claims and equivalents thereof.

100: area camera 200: tray member
210: through hole 211: locking jaw
300: lens 400: image side lighting
410: hole 411: inclined portion
500: lower lighting unit 510: receiving unit
600: LED 700: Conveyor
710: installation worker

Claims (7)

In the vision inspection device that the lens having a variety of curved surface is photographed by the area camera through the illumination of the illumination unit, and determines whether the lens is defective according to the determination of the photographed image,
An area camera whose height is adjusted in the vertical direction to adjust the focus according to the shape change of the lens;
A tray member having a plurality of through holes penetrating the upper and lower surfaces thereof, and a locking means provided on an inner circumferential surface of the through hole, the lens having the lens hooked on the locking means;
It is installed between the area camera and the tray member, the through-hole is formed in the center to increase in diameter from the upper side to the lower side so that the inclined portion is formed on the inner circumferential surface of the hole, the plurality of LEDs are installed in the inclined portion An upper illumination unit for allowing the light source to be inclinedly irradiated on the upper surface of the tray member; And
The lower side of the tray member is installed at a predetermined interval, the lower side lighting unit is provided with a plurality of LEDs in the upper receiving portion; Vision inspection apparatus for a lens using an area camera comprising a.
The method of claim 1,
LED installed in the inclined portion of the upper lighting unit is a vision inspection apparatus for a lens using an area camera, characterized in that the angle adjustment is installed manually or automatically.
The method according to claim 1 or 2,
Vision inspection apparatus for a lens using an area camera, characterized in that the LED installed in the inclined portion of the upper lighting unit is arranged in a single row or a plurality of rows along the inclined portion.
The method of claim 1,
The lower lighting unit by installing a diffuser plate on the top of the LED vision inspection apparatus for a lens using an area camera, characterized in that the illumination of the LED to be illuminated on the tray member as a whole.
The method of claim 1,
The locking means may be configured such that the diameter of the through hole is gradually smaller from the upper side to the lower side so that the outer edge of the lens fitted from the upper side of the through hole is caught and fixed between the upper side and the lower side of the inner circumferential surface of the through hole. Vision inspection device of the lens using an area camera.
6. The method according to claim 1 or 5,
The locking means, by forming a locking step on the inner circumferential surface of the through hole so that the outer edge of the lens seated on the locking step can be fixed to the vision camera using an area camera.
In the inspection method of the vision inspection device that the lens having a variety of curved surface is photographed by the area camera through the illumination of the illumination unit, and determines whether the lens is defective according to the determination of the photographed image,
A product loading process in which a plurality of lenses to be inspected in the tray member are loaded and then transported by a conveyor and stopped in the vision inspection waiting section;
A product washing process in which air is sprayed onto the lens of the tray member which is stopped in the vision inspection waiting section to clean the lens;
After the lens cleaning process is completed, the light is irradiated from the upper and lower lighting units installed in the vision inspection section while the lens is moved to the vision inspection section, and the area camera moves up and down along the curved surface of the lens to focus the lens. While photographing the lens, the upper surface of the tray member is moved in the zigzag direction, and the lenses loaded on the tray member are sequentially photographed one by one, and the photographed images are transmitted to a computer, and the inspection process of the product is analyzed and judged by an algorithm. ;
Defective product marking process that indicates that the defective lens is found through the product inspection process;
A product unloading process in which a lens marked as defective by a defective product marking process is removed by an operator;
Vision inspection method of the lens using an area camera comprising a.

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