Image based display glass defect inspection system

Abstract

The image-based display glass defect inspection system according to the present invention is characterized by comprising: a stand formed to allow a display glass to be tested to be mounted; a lighting unit formed inside the stand and irradiating light to check for defects in the display glass to be tested; a driving unit formed at the bottom of the stand and rotating and turning the stand to vary the inspection position of the display glass to be tested; a shooting unit that photographs the display glass to be tested according to the rotation and turning state of the stand; and a control unit formed inside the driving unit that controls the inspection conditions of the display glass to be tested by controlling the driving unit and the lighting unit, and determines whether there is a defect by comparing the image information of the display glass to be tested provided by the shooting unit with the image information of a defect-free standard display glass.

Description

Technology Field

[0001] The present invention relates to an image-based display glass defect inspection system, and more specifically, to an image-based display glass defect inspection system for determining whether there is a defect by analyzing image information of a display glass captured under various optical conditions. Background Technology

[0003] Generally, to determine defects in display glass, such as bubbles or scratches, methods are used in which a person directly inspects the glass with their eyes or uses lasers and light change sensors to detect sudden light changes occurring at the defect site.

[0004] However, judging defects by human eyes had the problem that when inspecting many display glasses, the high level of worker fatigue due to prolonged concentration caused minor defects to be missed or productivity to decrease.

[0005] In addition, according to Korean Published Patent No. 10-2009-0068945, determining defects using lasers and light change sensors had the problem that it was difficult to accurately determine complex defects because it could only detect defects of a specific thickness or at a specific location.

[0006] In addition, since inspections are primarily performed on only a single side, it is difficult to conduct inspections from multiple angles, which presented a problem in determining the presence of defects under various optical conditions. Prior art literature

[0008] Korean Patent Publication No. 10-2009-0068945 (Published June 29, 2009) The problem to be solved

[0009] The objective of the present invention is to provide an image-based display glass defect inspection system that accurately determines complex and various defects without missing minute defects of the display glass, which has been devised to solve the problems described above.

[0010] Another objective of the present invention is to provide an image-based display glass defect inspection system that can perform inspections from various angles and accurately determine whether there are defects in the display glass even under various optical conditions. means of solving the problem

[0012] To achieve the above objective, the image-based display glass defect inspection system according to the present invention is characterized by comprising: a stand formed to allow a display glass to be tested to be mounted; a lighting unit formed inside the stand and irradiating light to check for defects in the display glass to be tested; a driving unit formed at the bottom of the stand and rotating and turning the stand to vary the inspection position of the display glass to be tested; a shooting unit that photographs the display glass to be tested according to the rotation and turning state of the stand; a control unit formed inside the driving unit that controls the inspection conditions of the display glass to be tested by controlling the driving unit and the lighting unit, and determines whether there is a defect by comparing the image information of the display glass to be tested provided by the shooting unit with the image information of a defect-free standard display glass.

[0013] In addition, the control unit is characterized by using a driving unit to rotate the mounting bracket 360° horizontally, and rotating it alternately in the directions of one side, the other side, one side, and the other side of the mounting bracket.

[0014] In addition, the driving unit is characterized by being composed of a rotating shaft formed to rotate 360°, a first rotating shaft formed on the upper part of the rotating shaft to allow the mounting bracket to rotate in one or the other direction, and a second rotating shaft formed on the upper part of the first rotating shaft to allow the mounting bracket to rotate in one or the other direction.

[0015] In addition, the control unit is characterized by adjusting the intensity of the light from a set minimum brightness to a maximum brightness each time the stand is rotated once.

[0016] In addition, the control unit compares the image information of the display glass for testing with the image information of the standard display glass on a pixel-by-pixel basis, and if there is a pixel with an error greater than a predetermined value, determines that the display glass for testing is defective. Effects of the invention

[0018] As described above, the image-based display glass defect inspection system according to the present invention has the effect of increasing the accuracy of defect detection by photographing the display glass from various angles and analyzing the image information.

[0019] In addition, the image-based display glass defect inspection system according to the present invention has the effect of shortening inspection time and significantly improving productivity by automatically analyzing image information of display glass captured under various optical conditions. Brief explanation of the drawing

[0021] FIG. 1 is a diagram briefly illustrating the configuration of an image-based display glass defect inspection system according to the present invention. FIG. 2 is a drawing showing the upper surface of a stand of an image-based display glass defect inspection system according to the present invention. FIG. 3 is a drawing illustrating the hinge part and the driving part of an image-based display glass defect inspection system according to the present invention. FIG. 4 is an exemplary diagram illustrating the rotation and tilting movements of a stand in an image-based display glass defect inspection system according to the present invention. FIG. 5 is an exemplary diagram illustrating the lighting unit of an image-based display glass defect inspection system according to the present invention. FIG. 6 is an example diagram for determining whether a display glass is defective in an image-based display glass defect inspection system according to the present invention. Specific details for implementing the invention

[0022] Specific structural or functional descriptions of embodiments according to the concept of the present invention disclosed herein are provided merely for the purpose of explaining embodiments according to the concept of the present invention, and embodiments according to the concept of the present invention may be implemented in various forms and are not limited to the embodiments described herein.

[0023] Embodiments according to the concept of the present invention may be subject to various modifications and may take various forms; therefore, embodiments are illustrated in the drawings and described in detail in this specification. However, this is not intended to limit the embodiments according to the concept of the present invention to specific disclosed forms, and includes all modifications, equivalents, or substitutions that fall within the spirit and scope of the present invention.

[0025] Hereinafter, preferred embodiments of the present invention will be described with reference to the attached drawings.

[0027] FIG. 1 is a simplified diagram illustrating the configuration of an image-based display glass defect inspection system according to the present invention; FIG. 2 is a diagram illustrating the upper surface of a stand of an image-based display glass defect inspection system according to the present invention; FIG. 3 is a diagram illustrating a hinge part and a driving part of an image-based display glass defect inspection system according to the present invention; FIG. 4 is an exemplary diagram illustrating the rotational and tilting movements of a stand of an image-based display glass defect inspection system according to the present invention; FIG. 5 is an exemplary diagram illustrating a lighting part of an image-based display glass defect inspection system according to the present invention; and FIG. 6 is an exemplary diagram of determining whether there is a defect in the display glass of an image-based display glass defect inspection system according to the present invention.

[0029] As illustrated in FIG. 1, the image-based display glass defect inspection system according to the present invention comprises a stand (100) formed to allow a display glass to be tested to be mounted, a lighting unit (200) formed inside the stand (100) to irradiate light, a driving unit (300) formed at the bottom of the stand (100) to vary the inspection position of the display glass to be tested, a shooting unit (400) to photograph the display glass to be tested, and a control unit (500) that controls the driving unit (300) and the lighting unit (200) and determines whether there is a defect based on image information provided by the shooting unit (400).

[0031] Referring to FIG. 2, the mounting bracket (100) includes a mounting portion (20) for stably fixing a display glass (10) for testing on its upper surface.

[0033] At this time, the mounting portion (20) secures the display glass without shaking through a plurality of fixing portions (30), and the fixing portions (30) operate by pushing the glass from the top, bottom, left, and right to secure it.

[0035] Here, the fixing part (30) may use a mechanism such as a spring, hydraulic, or elastic material to fix the display glass (10) for testing.

[0037] First, the spring-type fixing part (30) fixes the test display fixing part (30) by pushing it from the top, bottom, left, and right.

[0038] At this time, since it is fixed using the elastic force of a spring, it can be applied to display glasses of various sizes and shapes, and the strength of the fixing force can be adjusted by adjusting the strength and length of the spring.

[0040] Secondly, the hydraulic fixing part (30) includes a hydraulic cylinder inside the fixing part (30) and fixes the display glass (10) for testing by the principle of pushing or pulling the cylinder as the fluid is compressed.

[0041] In other words, by precisely adjusting the fluid pressure, it is possible to provide a stable fixing force without damaging the display glass, and it can be applied to display glasses of various sizes and thicknesses.

[0043] Thirdly, the fixing part (30) utilizing an elastic material provides the necessary support force to secure the display glass (10) for testing without shaking by wrapping around and closely adhering to the display glass through a certain level of deformation when the display glass is seated.

[0045] As illustrated in FIG. 3, the driving unit (300) is composed of a rotation axis (310) that allows the mounting bracket (100) to rotate 360˚ in the horizontal direction, a first rotation axis (320) that allows the mounting bracket (100) to rotate in the direction of one side and the other side, and a second rotation axis (330) that allows the mounting bracket (100) to rotate by a certain angle in the direction of one side and the other side.

[0047] At this time, the driving unit (300) is equipped with a first driving unit (not shown) that drives a rotation shaft (310), a first driving unit (not shown) that drives a first rotation shaft (320), and a third driving unit (not shown) that drives a second rotation shaft (330) to enable rotation and rotation.

[0049] Here, the first drive unit may use a DC motor capable of continuous rotation for 360˚ rotation of the rotation axis (310) and easily controllable rotation speed and direction, or a stepper motor capable of precise rotation angle adjustment.

[0051] In addition, a servo motor capable of precise angle adjustment and pre-setting of angles may be used to enable the first driving unit to rotate in the direction of one side and the other side of the mounting bracket (100).

[0053] Likewise, a servo motor capable of precise angle adjustment and pre-setting of angles may be used to rotate the third drive unit in the direction of one side and the other side of the stand (100).

[0055] If the display glass (10) for the test is large and heavy, it can be applied to the first drive unit and the first drive unit of the hydraulic cylinder type to enable stable rotation even under high load.

[0057] That is, as illustrated in FIG. 4, the stand (100) can be rotated at a preset angle within a range of 360˚ by the rotation axis (310), and can be rotated in the direction of one side, the other side, one side, and the other side of the stand (100) by a certain angle by the first rotation axis (320) and the second rotation axis (330).

[0059] At this time, whenever the mounting bracket (100) is rotated by a certain angle by the rotation axis (310), it can rotate in the direction of one side, the other side, one side, and the other side by a preset angle by the first rotation axis (320) and the second rotation axis (330).

[0061] In one embodiment, if the angle of rotation by the rotation axis (310) is 45˚ and the angle of rotation by the first rotation axis (320) and the second rotation axis (330) is 10˚, the stand (100) rotates 8 times, and with each rotation, the display glass (10) for testing rotates alternately by 10˚ in the direction of one side, the other side, one side, and the other side of the stand (100).

[0063] In addition, the above-mentioned stand (100) is equipped with a lighting unit (200) that illuminates a certain amount of light on the lower part of the display glass (10) for testing.

[0065] As shown in FIG. 5, a lighting unit (200) is formed on the inner outer side of the stand (100) so that light can be shone obliquely in the direction of the arrow at a certain angle onto the display glass (10) for testing.

[0067] At this time, the angle at which the lighting unit (200) shines light can be adjusted to match the size and shape of the display glass (10) for testing, and the brightness of the light shone by the lighting unit (200) can also be adjusted.

[0069] The above-mentioned shooting unit (400) is positioned to photograph the upper surface of the mounting bracket (100) to photograph the display glass (10) for testing that is fixed to the mounting bracket (100), and can acquire image information of the display glass according to the rotation and tilting of the mounting bracket (100).

[0071] At this time, the above-mentioned shooting unit (400) continues to shoot video while the stand (100) rotates 360˚ to acquire image information of the display glass for all angles and brightness of the lighting that match the optical conditions set in the control unit (500).

[0073] In addition, the above-mentioned shooting unit (400) must be defined as a high-resolution camera capable of accurately capturing defects such as fine scratches and must be able to accurately acquire image information even in light environments of various brightness levels.

[0075] The above control unit (500) is formed inside the driving unit (300) and can control the rotation, tilt, angle and brightness of the mounting bracket (100) described above according to the optical conditions for detecting defects.

[0077] At this time, since the fixing force increases as the size of the display glass increases, the control unit (500) measures the fixing force of the fixing unit (30) that changes according to the size of the display glass (10) for testing and calculates the size of the display glass.

[0079] After that, the control unit (500) adjusts the angle of the light according to the calculated size so that the light is evenly distributed on the surface, and the larger the display glass, the more finely the rotation angle and tilt angle of the stand (100) are set.

[0081] In addition, the control unit (500) automatically sets the lighting angle, rotation angle, and tilt angle optimized for each size by referring to a reference value (e.g., a first size reference value, a second size reference value, a third size reference value, etc.) set according to the size of the display glass (10) for testing.

[0083] At this time, the control unit (500) adjusts the brightness of the light from a set minimum value to a maximum value whenever the stand (100) is tilted.

[0084] Here, the minimum brightness and maximum brightness of the light input to the control unit (500) can be set to 500 LUX and 5000 LUX, respectively, and can be adjusted to other values ​​as needed.

[0086] The control unit (500) determines whether there is a defect in the display glass (10) for testing based on the image information received from the shooting unit (400).

[0088] At this time, as illustrated in FIG. 6, the control unit (500) stores image information of a standard display glass (10a) that is free of defects in advance and determines whether there is a defect by comparing it with image information of a display glass (10) for testing.

[0090] Here, the control unit (500) uses a learned deep learning algorithm to recognize a defective area of ​​the display glass (10) for testing, and based on this, determines a defect by comparing it with image information of the standard display glass (10a).

[0092] At this time, the image information of the standard display glass (10a) stored in the control unit (500) is image information that takes into account rotation and tilt while fixed to the upper surface of the stand (100), and the image information in a state that matches the rotation and tilt conditions of the display glass (10) for testing is retrieved.

[0094] In addition, the control unit (500) compares two image information by considering color, saturation, and brightness on a pixel-by-pixel basis.

[0096] At this time, the control unit (500) calculates a defect score by giving a large weight to the color difference in each difference, then to saturation, and finally to brightness.

[0098] Here, the control unit (500) can calculate a defect score through Equation (1).

[0099] Equation (1)

[0100] : Defect score, : Color weight, : Color difference,

[0101] : Saturation weight, : Saturation difference, : Brightness weight,

[0102] : Brightness difference

[0104] The defect score calculated as above ( ) set tolerance( If the value is greater than ) the display glass (10) for the test is determined to be defective.

[0106] That is, the control unit (500) can detect not only fine scratches but also foreign substances or bubbles contained in the display glass (10) for testing by comparing them at the pixel level, so that it can determine whether there is a defect more accurately.

[0108] As described above, although the present invention has been described with reference to preferred embodiments with reference to the accompanying drawings, it is evident to those skilled in the art that many obvious variations are possible from this description without departing from the scope of the invention. Accordingly, the scope of the invention should be interpreted by the claims described to include examples of such many variations. Explanation of the symbols

[0110] 10: Display glass for P-test 20 : Seating part 30 : Fixed part 100 : Stand 200 : Lighting section 300 : Drive unit 310 : Rotation axis 320 : 1st rotational shaft 330 : Second pivot shaft 400 : Filming Department 500 : Control unit

Claims

Claim 1 An image-based display glass defect inspection system characterized by comprising: a stand formed to allow a display glass for test to be mounted; a lighting unit formed inside the stand and irradiating light to check for defects in the display glass for test; a driving unit formed at the bottom of the stand and rotating the stand to vary the inspection position of the display glass for test; a shooting unit that photographs the display glass for test according to the rotational and rotating state of the stand; and a control unit formed inside the driving unit, which controls the driving unit and the lighting unit to control the inspection conditions of the display glass for test, and determines whether there is a defect by comparing the image information of the display glass for test provided by the shooting unit with the image information of a defect-free standard display glass. Claim 2 An image-based display glass defect inspection system according to claim 1, wherein the control unit rotates the mounting bracket 360° horizontally using the driving unit, and alternately rotates the mounting bracket in the directions of one side, the other side, one side, and the other side. Claim 3 In claim 2, the driving unit comprises: a rotation shaft formed to be rotatable 360°; a first rotation shaft formed on the upper part of the rotation shaft so as to rotate the mounting bracket in one or the other direction; and a second rotation shaft formed on the upper part of the first rotation shaft so as to rotate the mounting bracket in one or the other direction; characterized in that the image-based display glass defect inspection system. Claim 4 In claim 2, the image-based display glass defect inspection system is characterized in that the control unit adjusts the intensity of the lighting from a set minimum brightness to a maximum brightness each time the mounting bracket is rotated once. Claim 5 An image-based display glass defect inspection system according to claim 1, wherein the control unit compares the image information of the display glass for test with the image information of the standard display glass on a pixel-by-pixel basis, and determines the display glass for test as defective if there is a pixel with an error greater than or equal to a predetermined value.

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