KR102503772B1 - Method for inspectiing display device, and apparatus for inspecting display device - Google Patents

Abstract

A method for inspecting a display device and a device for inspecting a display device are provided. A method for inspecting a device of a display sets a focus on a display device including a plurality of layers, and an image capture unit displays a plurality of first images from the first light reflected to the focus under a first lighting condition in which a first light is irradiated. Acquiring images, acquiring a plurality of second video images from the second light reflected on the focal point under a second lighting condition in which the second light is irradiated, and defective particles of the display device from the acquired video images. obtaining information on defective candidates found, and applying a pass/fail decision to the defective candidates, wherein the image photographing unit determines a mirror array in which a plurality of mirrors are tilted with inclination angles, and the inclination angles of the mirrors. A system control unit is included, and the position of the focal point is set according to the inclination angles of the mirrors.

Description

Display device inspection method and display device inspection device

The present invention relates to a display device inspection method and a display device inspection device. More specifically, the present invention relates to a method for inspecting a display device for inspecting defects in appearance of each layer of a display device in which a plurality of layers are stacked, and an inspection device for a display device.

Display devices are increasing in importance with the development of multimedia. In response to this, various types of display devices such as an organic light emitting display (OLED) and a liquid crystal display (LCD) are being used.

A device for displaying an image of a display device includes a display panel such as an organic light emitting display panel or a liquid crystal display panel. Among them, the light emitting display panel may include a light emitting device. For example, in the case of a light emitting diode (LED), an organic light emitting diode using an organic material as a light emitting material and an inorganic light emitting diode using an inorganic material as a light emitting material etc.

A display device may include a plurality of layers, such as a light source for emitting light, a driving layer for driving the light source, and a plurality of optical layers through which light emitted from the light source passes. Each layer may be sequentially formed in a continuous process, but may be individually formed and bonded or attached to each other to form one display device. In a display device including a plurality of layers, defective particles may exist in each layer along the stacking direction. The inspection device of the display device may perform inspection in a manner of individually detecting defective particles present in each layer.

As a method of inspecting a display device having a plurality of layers, a method of acquiring images for each layer while moving a 2D camera along a direction in which the layers of the display device are stacked may be used. As the 2D camera moves directly, shooting is performed to detect defective particles present on each layer. As the camera moves, the mechanism vibrates, and blur or focus deviation may occur in the image. . To compensate for this, a light field camera can be used, but it has limitations in controlling the loss of resolution and the Z-axis resolution of the acquired image in units of several μm.

The problem to be solved by the present invention is a method for inspecting the exterior of a display device composed of a plurality of layers, in which an image of each layer is acquired by an imaging system using a mirror, and an exterior inspection using an algorithm that detects defective particles therefrom. to provide the device.

An object to be solved by the present invention is to provide an inspection device for a display device including an image capturing unit using an imaging system and a process unit detecting defective particles from images acquired therefrom.

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

In a method for inspecting a display device according to an embodiment for solving the above problems, a focus is set on a display device including a plurality of layers, and an image capture unit reflects the focus on the focus under a first lighting condition in which a first light is irradiated. obtaining a plurality of first video images from the first light, and acquiring a plurality of second video images from the second light reflected on the focal point under a second lighting condition in which the second light is irradiated; obtaining information on bad candidates in which bad particles of the display device are found from the obtained video images, and applying a pass/fail decision to the bad candidates, wherein the image capture unit has a plurality of mirrors having inclination angles, A tilted mirror array and a system control unit controlling tilt angles of the mirrors are included, and the position of the focal point is set according to the tilt angles of the mirrors.

The obtaining of the video image further includes determining whether additional video images need to be acquired, and when the additional video images need to be acquired, the system control unit of the video photographing unit controls inclination angles of the mirrors to obtain the additional video images. A position of focus may be moved in a direction in which the layers of the display device are stacked, and the first video image and the second video image may be further acquired at different focus positions.

The system control unit of the image capturing unit may move the focal point to a first interval or a second interval based on the position of the previous focal point, and the first interval may be smaller than the second interval.

The system control unit of the image photographing unit moves the focal point at the first interval when the previous focal point is located on the outermost surface of the display device, and when the previous focal point is located inside the display device. The focal point may be moved at the second interval.

In the step of determining whether additional video image acquisition is necessary, if the location to which the focus is moved is located outside the display device, determining that the additional video image acquisition is not necessary and acquiring information on the defective candidates can be performed.

Obtaining information on the bad candidates may include selecting bad candidates from among the obtained video images, and extracting location information of the bad candidates in the display device from the bad candidates.

The selecting of the bad candidates includes checking whether the bad particles are found among the obtained video images, extracting geometric information of the bad particles from the video images in which the bad particles are found, and The method may include determining an intrinsic defective particle based on the geometrical information of the defective particle.

Determining the intrinsic defective particles based on the geometric information of the defective particles may include comparing the geometric information of the defective particles with geometric information of defective particles found in a plurality of other video images to set a threshold value for determining defects. and determining the defective particle as the intrinsic defective particle by comparing the critical value with the geometrical information of the defective particle.

Applying the pass/fail decision to the bad candidates may include determining whether the display device can be repaired or discarded based on location information of the bad candidates.

In the step of applying the pass/fail decision to the defective candidates, when the location of the defective particles of the defective candidates is located on the uppermost layer of the display device, it may be determined that the repair is possible.

The image photographing unit is arranged to lie on the same axis as the display device, the first light is irradiated to the display device in a direction parallel to the axis, and the second light is emitted to the display device in a direction inclined to the axis. device can be investigated.

The first light may be irradiated in a direction perpendicular to the axis and propagated in the same direction as the axis by a light path conversion unit disposed on the axis.

The obtaining of the video image may further include obtaining a third video image from the third light reflected from the focal point by irradiating third light emitted in a direction perpendicular to the axis.

The step of applying the pass/fail decision to the defective candidates may include determining that the defective particles found in the third video image are pseudo-defective particles.

The first light and the second light may be ultraviolet light, and the first light and the second light reflected by the focal point may be incident to the image capture unit through an optical filter that selectively transmits the ultraviolet light.

An inspection apparatus for a display device according to an embodiment for solving the above problem is a inspection apparatus for a display device including a plurality of layers, which is arranged on the same axis as the display device to obtain video images of the display device. An image photographing unit, a first lighting unit radiating a first light to the display device in the same direction as the axis, and a second lighting unit radiating a second light in a direction inclined to the axis, and the image capturing unit acquires and an image processing unit that obtains information of bad candidates in which bad particles of the display device are found from the video images, and the image photographing unit comprises a mirror array in which a plurality of mirrors are tilted at an inclination angle, and in the mirror A mirror imaging system including a sensor unit for sensing reflected light to obtain a video image, and a system control unit for adjusting inclination angles of the mirrors, wherein the system control unit adjusts the inclination angles of the mirrors to focus the display device. and the sensor unit acquires a first video image and a second video image from the first light or the second light reflected from the focal point, respectively.

The image photographing unit moves the focal point in the direction in which the layers of the display device are stacked by the system controller controlling the inclination angles of the mirrors, and captures the first video image and the second video image at different focal positions. more can be obtained.

The image processing unit may select the bad candidates among the video images acquired by the image capturing unit, and extract location information of the bad candidates in the display device from the bad candidates.

The image processing unit may check whether the defective particle is found among the obtained image images and extract geometric information of the defective particle from the image images in which the defective particle is found.

Each of the first lighting unit and the second lighting unit may further include an optical filter that emits ultraviolet light and is disposed between the image photographing unit and the display device to selectively transmit ultraviolet light.

Other embodiment specifics are included in the detailed description and drawings.

According to an embodiment, the inspection apparatus of the display device may acquire video images on a plurality of layers by adjusting the focus without directly moving the image capture unit through the mirror imaging system. In the external inspection of the display device using this, clear image images can be obtained, and information on defective particles can be extracted from the obtained image images. In addition, based on the information of the defective particles, it is possible to determine whether or not repair is possible along with determining whether the product is good or bad.

Effects according to the embodiments are not limited by the contents exemplified above, and more various effects are included in this specification.

1 is a schematic diagram of a device for inspecting a display device according to an exemplary embodiment.
2 and 3 are schematic diagrams illustrating a method of photographing an object at a first focal length by an image photographing unit in an inspection device of a display device according to an exemplary embodiment.
4 and 5 are schematic diagrams illustrating a method of photographing an object at a second focal length by an image photographing unit in an inspection device of a display apparatus according to an exemplary embodiment.
6 is a schematic diagram illustrating an inspection using a second lighting unit in an inspection apparatus for a display device according to an exemplary embodiment.
7 is a schematic diagram illustrating a first video image obtained by using a first lighting unit in an inspection device of a display device according to an exemplary embodiment.
8 is a schematic diagram illustrating a second video image obtained by using a second lighting unit in an inspection device of a display device according to an exemplary embodiment.
9 is a schematic diagram illustrating an operation of a laser unit in a device for inspecting a display device according to an exemplary embodiment.
10 is a schematic cross-sectional view illustrating a display device according to an exemplary embodiment.
11 is a cross-sectional view illustrating a display substrate and a color conversion substrate in a display device according to an exemplary embodiment.
12 is a plan view illustrating one sub-pixel of a display substrate in a display device according to an exemplary embodiment.
13 is a cross-sectional view taken along the line Q1-Q1' of FIG. 12;
14 is a schematic diagram illustrating a light emitting element disposed on a display substrate of a display device according to an exemplary embodiment.
15 is a flowchart illustrating a method of inspecting a display device according to an exemplary embodiment.
16 is a flowchart illustrating in detail a video image acquisition step in a method for inspecting a display device according to an exemplary embodiment.
17 is a flowchart illustrating in detail the step of controlling the focus position in the video image acquisition step of FIG. 16 .
18 is a flowchart illustrating in detail an information acquisition step of bad candidates in a method for inspecting a display device according to an exemplary embodiment.
19 is a flowchart illustrating in detail a step of selecting bad candidates in a method for inspecting a display device according to an exemplary embodiment.
20 is a flowchart illustrating in detail a step of applying pass/fail determination to bad candidates in a method for inspecting a display device according to an exemplary embodiment.
21 is a schematic diagram illustrating an operation of a third lighting unit in an inspection apparatus for a display device according to another embodiment.
FIG. 22 is a flowchart illustrating in detail a video image acquisition step in the inspection method using the inspection device of the display device of FIG. 21 .

Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the detailed description of the following embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various different forms, only these embodiments make the disclosure of the present invention complete, and common knowledge in the art to which the present invention belongs. It is provided to fully inform the holder of the scope of the invention, and the present invention is only defined by the scope of the claims.

When an element or layer is referred to as “on” another element or layer, it includes all cases in which another element or layer is directly on top of another element or another layer or other element is interposed therebetween. Likewise, those referred to as "Below", "Left", and "Right" are all interposed immediately adjacent to other elements or interposed with another layer or other material in the middle. include Like reference numbers designate like elements throughout the specification.

Although first, second, etc. are used to describe various components, these components are not limited by these terms, of course. These terms are only used to distinguish one component from another. Accordingly, it goes without saying that the first element mentioned below may also be the second element within the technical spirit of the present invention.

Hereinafter, embodiments will be described with reference to the accompanying drawings.

1 is a schematic diagram of an inspection device for a display device 10 according to an exemplary embodiment.

Referring to FIG. 1 , the inspection device 100 of the display device 10 includes an image capturing unit 110 , a plurality of lighting units 130 and 150 , and an image processing unit 180 . In addition to the above units, the inspection device 100 of the display device 10 includes an optical filter 105 used for image acquisition in the image capturing unit 110, an optical path conversion unit 107, and a laser unit 190. etc. may be further included. The inspection apparatus 100 of the display apparatus 10 acquires a plurality of images from the display apparatus 10 to be inspected by using the lighting units 130 and 150 and the image capture unit 110, and obtains the acquired images. From these, whether or not the display device 10 is defective can be inspected. In particular, the inspection device 100 of the display device 10 according to an embodiment may select defective particles from images obtained from the inspection subject and extract location information thereof, and from there, the appearance defect of the inspection subject, that is, the display It is possible to check whether the external appearance of the device 10 is defective.

The imaging unit 110 may acquire a plurality of video images from the examination target. Light irradiated from the plurality of lighting units 130 and 150 may be reflected and incident to the image capture unit 110, and the image capture unit 110 senses the light to obtain a video image of the test target. can be obtained. The image capture unit 110 may be disposed on one side of the base part 101 through which light reflected from the inspection target passes, and the light receiving unit 103 facing the inspection target may be disposed on the other side of the base unit 101 . Light emitted from the lighting units 130 and 150 may be reflected from the inspection target and incident to the light receiving unit 103 while photographing the inspection target. Based on the base part 101, the inspection target, the light receiver 103, and the image capture unit 110 may be placed on the same axis, and the light incident on the light receiver 103 is incident on the image capture unit 110. and can be sensed as a video image. However, it is not limited thereto, and the relative arrangement of the image capture unit 110 and the inspection target may be variously modified. The arrangement of the inspection apparatus 100 of the display apparatus 10 illustrated in FIG. 1 may be one example of arrangements in which the image photographing unit 110 may easily receive light reflected from an inspection target.

According to an embodiment, the image capturing unit 110 may include a mirror imaging system 111 capable of adjusting a focus according to a position of an examination target and a system controller 113 capable of controlling the mirror imaging system 111. can As will be described later, the inspection target of the inspection device 100 of the display device 10 may be the display device 10 composed of a plurality of layers, and the inspection device 100 is an image image for each layer of the display device 10. can be obtained. In order to obtain video images according to the location of each floor, when light is irradiated at a certain angle from the lighting units 130 and 150, the image capturing unit 110 adjusts the focus to obtain different video images by light reflected from different floors. can be obtained.

2 and 3 are schematic diagrams illustrating a method of photographing an object at a first focal length by an image photographing unit in the inspection device of the display apparatus 10 according to an exemplary embodiment. 4 and 5 are schematic diagrams illustrating a method of photographing an object at a second focal length by an image photographing unit in the inspection device of the display apparatus 10 according to an exemplary embodiment. 2 to 5 schematically illustrate a process of obtaining a video image in the image capture unit 110 under a first lighting condition in which a first lighting unit 130 to be described later irradiates light.

Referring to FIGS. 2 to 5 in addition to FIG. 1 , the mirror imaging system 111 of the image capturing unit 110 may include a mirror array MA and a sensor unit S. The mirror array MA may include a plurality of mirrors M inclined at different inclination angles according to positions. The mirrors M disposed on the same axis from the object OB are not tilted, and the tilt angles of the mirrors M spaced apart from the same axis may increase according to the distance from the same axis. The light reflected from the object OB is reflected from the mirror M of the mirror array MA and is incident to the sensor unit S, and the sensor unit S can obtain an image of the inspection target from the incident light. there is. Although not particularly limited, the sensor unit S may be a CCD (Charge Coupled Device) sensor or a CMOS image sensor (Complementary Metal Oxide Semiconductor Image Sensor, CIS).

According to an embodiment, the mirror imaging system 111 adjusts inclination angles θ1 and θ2 at which the mirrors M of the mirror arrays MA are tilted according to the position of the object OB to adjust the focal distances F1 and F2. can control. The image photographing unit 110 may acquire video images of the object OB located at different positions by controlling the focal distances F1 and F2 of the mirror imaging system 111 .

For example, when the first light L1 irradiated from the first lighting unit 130 is reflected from the inspection target and incident to the image photographing unit 110, the reflected first light L1 ′ is a mirror array ( Among the mirrors M of the MA), the outermost mirror spaced apart from the same axis as the object OB may be inclined at a first inclination angle θ1. The reflected first light L1' may be reflected again from the mirror M tilted at the first inclination angle θ1 and may be incident to the sensor unit S. In a state where the mirror M of the mirror array MA is tilted at the first inclination angle θ1, the imaging unit 110 may obtain a video image of the object OB located at the first focal distance F1. there is.

On the other hand, in the inspection apparatus 100 of the display device 10 according to an embodiment, 'focus', 'focal distance', or 'focus position' refers to the reflected light received by the image capture unit 110 reflected object (OB). ) can be defined by the position of As shown in the drawing, if the object OB is located at a first focal distance F1 from the image capturing unit 110 and the image capturing unit 110 sets the first focal distance F1 as a focus or a focus position, The sensor unit S of the image capturing unit 110 may obtain a video image by sensing only the light L1' reflected from the object OB located at the first focal distance F1. On the other hand, if the image capture unit 110 sets another location as the focal point or focus location, the sensor unit S may not be able to sense the light reflected from the object OB located at the first focal distance F1. That is, the image capturing unit 110 of the inspection device 100 of the display device 10 may obtain a video image by selectively receiving only the light reflected by the object OB located at the set focal point among the reflected lights. there is. The focus or focus position set by the image capture unit 110 may be the position of the object OB that reflects the light emitted from the lighting units 130 and 150 .

Here, in order to obtain a video image from the object OB at a different location or at a different focal distance, the mirror imaging system 111 may adjust an inclination angle of the mirror M of the mirror array MA. The system controller 113 of the image capturing unit 110 may control the inclination angles of the mirrors M of the mirror array MA included in the mirror imaging system 111, and the image capturing unit 110 may perform mirror imaging. A video image may be acquired from an object OB located at a different focal length of the system 111 . When the outermost mirror among the mirrors M of the mirror array MA is tilted at a second tilt angle θ2 different from the first tilt angle θ1, the object OB located at the second focal distance F2 The reflected first light L1 ′ may be reflected from the mirror M and incident to the sensor unit S. That is, the object OB of the reflected light incident to the sensor unit S may vary according to the inclination angles θ1 and θ2 of the mirror M of the mirror array MA.

The focus control method of the image capturing unit 110 has an advantage in that a video image can be acquired according to the position of the object OB even if the image capturing unit 110 does not directly move in an axial direction. When the image capture unit 110 moves to obtain an image according to the location of the object OB, particularly in the axial direction, based on a certain inspection target, the focus is shaken due to vibration caused by the movement, or the resolution of the image is reduced. There is a problem with lowering. In addition, a preparation time before imaging is required from the movement operation of the image capture unit 110 to the focus acquisition operation, so inspection time may increase. The inspection apparatus 100 of the display apparatus 10 according to an embodiment can acquire a plurality of image images according to the position of an object OB of an inspection target by a focus control method using a mirror array MA even without axial movement. can

The plurality of lighting units 130 and 150 may radiate light to the inspection target. When the lighting units 130 and 150 radiate light to the inspection target, the image capture unit 110 may acquire a plurality of video images by sensing light reflected from the inspection target.

As shown in FIG. 3 , the first lighting unit 130 may be a coaxial lighting unit that emits light in a direction perpendicular to the upper surface of the inspection target. The image capture unit 110 and the inspection target may be placed on the same axis, and the first light L1 radiated from the first lighting unit 130 may be radiated to the inspection target on the same axis.

According to one embodiment, the first lighting unit 130 is disposed spaced apart on the same axis on which the image capturing unit 110 and the inspection target are placed, and may irradiate light in a direction perpendicular to the same axis. The first lighting unit 130 is disposed on the side of the base portion 101, and may be disposed not parallel to the same axis on which the image capturing unit 110 and the inspection target are disposed. The inspection device 100 of the display device 10 includes a light path conversion unit 107 disposed in the base portion 101, and the first lighting unit 130 emits light toward the light path conversion unit 107. can be investigated The light path conversion unit 107 may convert the path of the light emitted from the first lighting unit 130 and radiate the light L1 to the inspection target along the same axis as the image photographing unit 110 . Even if the first lighting unit 130 is not disposed on the same axis as the image capturing unit 110 , the first lighting unit 130 may be used as coaxial lighting through the optical path conversion unit 107 .

6 is a schematic diagram illustrating an inspection using a second lighting unit in the inspection apparatus of the display apparatus 10 according to an exemplary embodiment.

In addition to FIGS. 1 and 3 , referring to FIG. 6 , the second lighting unit 150 may be quasi-coaxial lighting that radiates light to the upper surface of the object to be inspected in an inclined direction, unlike the first lighting unit 130 . Light emitted from the second lighting unit 150 may be radiated to the test target in a direction inclined from the same axis on which the image capture unit 110 and the test target are placed. The second lighting unit 150 includes a plurality of lighting units, for example, a first lighting unit 151 and a second lighting unit 153, and the first lighting unit 151 and the second lighting unit 153 are the image capturing unit 110 It may be located on both sides of the same axis on which it is placed. The light emitted from the first lighting unit 151 and the light emitted from the second lighting unit 153 may be inclined in opposite directions from the same axis on which the image capturing unit 110 is placed.

FIG. 7 is a schematic diagram illustrating a first video image obtained by using a first lighting unit in an inspection device of a display apparatus 10 according to an exemplary embodiment. 8 is a schematic diagram illustrating a second video image obtained by using a second lighting unit in the inspection device of the display apparatus 10 according to an exemplary embodiment.

Referring to FIGS. 6 and 7 , the first lighting unit 130 and the second lighting unit 150 operate opposite to each other and may not simultaneously emit light. The image photographing unit 110 acquires a first video image IM1 under a first lighting condition in which the first lighting unit 130 emits light, and in a second illumination in which the second lighting unit 150 emits light Under the condition, the second video image IM2 may be obtained. Depending on the angle of incidence of light irradiated onto the inspection target, the shape or brightness of video images acquired by the image capture unit 110 may be different. The inspection device 100 of the display device 10 acquires video images of different brightness when photographing the same inspection target, and through their contrast, identification of the defective particles P may be easy. The defective particles P may appear in the form of foreign matter, scratches, cracks, or pressure on the surface or inside of the inspection target. The image processing unit 180 to be described later may also perform an algorithm for distinguishing the type of bad particle P from the shape of the bad particle P found in the video image.

According to one embodiment, the first lighting unit 130 and the second lighting unit 150 may include a UV light source. The first lighting unit 130 and the second lighting unit 150 emit ultraviolet light, and one side of the base portion 101 on which the image capture unit 110 is disposed is an optical filter 105 that selectively transmits ultraviolet light. ) can be placed.

As will be described later, the display device 10 to be inspected is composed of a plurality of layers, and some of the layers may include materials having different refractive indices. The light irradiated to the display device 10 may cause irregular reflection depending on the difference in refractive index of the material, and distortion may occur in the image acquired by the image capture unit 110, making it difficult to determine defective particles. To prevent this, the inspection device 100 of the display device 10 according to an embodiment may acquire a clear image by using light of a specific wavelength range, for example, ultraviolet light, according to the material included in the inspection target. The first lighting unit 130 and the second lighting unit 150 each include an ultraviolet light source, and the optical filter 105 disposed before light reaches the image capturing unit 110 from the image base unit 101 Only light of a specific wavelength range or polarized light may be transmitted through the photographing unit 110 .

In FIG. 1 , a structure in which the inspection device 100 of the display device 10 includes only the first lighting unit 130 and the second lighting unit 150 is illustrated, but is not limited thereto. When more images taken under different lighting conditions are needed in processing the structure of the object to be inspected and the video images, the inspection device 100 of the display device 10 may include a larger number of lighting units.

The image processing unit 180 may obtain information on bad candidates from the video images acquired by the image capture unit 110 and apply a pass/fail decision to the bad candidates. According to an embodiment, the image processing unit 180 may include an algorithm for selecting bad candidates from a plurality of acquired video images, an algorithm for extracting layer-by-layer positions and location information of bad particles from the bad candidates, and information on bad candidates. It may include a pass/fail decision algorithm. The external inspection of the display device 10 performed using the inspection device 100 of the display device 10 is aimed at finally determining whether the display device 10 is good or bad. The video images acquired in the process are selected through a series of algorithms, and a pass/fail decision application algorithm may be performed based on information obtained therefrom. An algorithm performed by the image processing unit 180 will be described later with reference to other drawings.

9 is a schematic diagram illustrating an operation of a laser unit in an inspection device of a display device 10 according to an exemplary embodiment.

Referring to FIG. 9 in addition to FIG. 1 , the laser unit 190 may be disposed adjacent to the light receiving unit 103 of the base unit 101 . The laser unit 190 may irradiate the laser LA to the upper surface of the inspection target and measure the distance from the light receiving unit 103 to the upper surface of the inspection target. The distance measured by the laser unit 190 may be provided as information necessary for the system controller 113 of the image capturing unit 110 to set a focus position on the surface of the object to be examined. However, the laser unit 190 may be omitted as needed.

Meanwhile, an inspection target of the inspection apparatus 100 of the display apparatus 10 may be the display apparatus 10 including a plurality of layers. The display device 10 may include a light source emitting light of a specific wavelength range, and the light may pass through a plurality of layers and be emitted to one side of the display device 10 . While the light is emitted, defective particles P present in the display device 10 may interfere with the light emission or be visible from the outside between transparent layers. The inspection device 100 of the display device 10 may be used to improve product reliability through determining whether the display device 10 is good or bad by inspecting the existence of defective particles P.

10 is a schematic cross-sectional view illustrating a display device according to an exemplary embodiment.

Referring to FIG. 10 , the display device 10 displays a moving image or a still image. The display device 10 may refer to any electronic device providing a display screen. For example, televisions, laptops, monitors, billboards, Internet of Things, mobile phones, smart phones, tablet PCs (Personal Computers), electronic watches, smart watches, watch phones, head-mounted displays, mobile communication terminals, An electronic notebook, an electronic book, a portable multimedia player (PMP), a navigation device, a game machine, a digital camera, a camcorder, and the like may be included in the display device 10 .

The display device 10 may include a display substrate 11 , a color conversion substrate 13 , at least one coupling member 15 , an optical film 17 and a protective film 19 . In the drawing, one coupling member 15 is illustrated as coupling the color conversion substrate 13 and the optical film 17 to each other, but is not limited thereto, and the display device 10 may include more coupling members 15. can In each layer of the display device 10 , defective particles, which are objects to be detected by the inspection device 100 of the display device 10 described above, may exist inside or on the surface. Referring to FIG. 10 , the uppermost layer of the display device 10 is the protective film 19, and the surface of the uppermost layer may be an upper surface of the protective film 19.

The display substrate 11 is a display panel that displays a screen or image. Examples of the display panel include an inorganic light emitting diode display panel, an organic light emitting display panel, a quantum dot light emitting display panel, a plasma display panel, and a field emission display panel. . Hereinafter, as an example of the display panel, a case in which an inorganic light emitting diode display panel is applied is exemplified, but the present invention is not limited thereto, and the same technical idea may be applied to other display panels if applicable. The color conversion substrate 13 may convert light emitted from a light emitting device, which is a light source of the display substrate 11 , into light of a specific wavelength range. Hereinafter, the display substrate 11 and the color conversion substrate 13 will be described in detail with reference to other drawings.

11 is a cross-sectional view illustrating a display substrate and a color conversion substrate in a display device according to an exemplary embodiment. 12 is a plan view illustrating one sub-pixel of a display substrate in a display device according to an exemplary embodiment. 13 is a cross-sectional view taken along the line Q1-Q1' of FIG. 12;

11 to 13 , the display substrate 11 of the display device 10 may include a plurality of pixels PX including a plurality of sub-pixels SPn (n is 1 to 3). For example, one pixel PX may include a first sub-pixel SP1 , a second sub-pixel SP2 , and a third sub-pixel SP3 .

Each sub-pixel SPn of the display substrate 11 may include an emission area EMA and a non-emission area. The light emitting area EMA is an area where the light emitting element ED is disposed and light of a specific wavelength range is emitted, and the light emitting element ED is not disposed and the light emitted from the light emitting element ED does not reach the non-light emitting area. This may be an area in which no light is emitted. In addition, each sub-pixel SPn may further include a sub-region SA disposed in the non-emission area. The sub area SA may be disposed on one side of the light emitting area EMA in the first direction DR1 and may be disposed between the light emitting areas EMAs of sub pixels SPn adjacent to each other in the first direction DR1. .

The second bank BNL2 may be arranged in a lattice pattern including portions extending in the first and second directions DR1 and DR2 on a plane. The second bank BNL2 may be disposed across the boundary of each sub-pixel SPn to distinguish neighboring sub-pixels SPn. In addition, the second bank BNL2 is disposed to surround the emission area EMA disposed in each sub-pixel SPn to distinguish them.

The display substrate 11 may include a first substrate SUB1, a semiconductor layer, a plurality of conductive layers, and a plurality of insulating layers disposed on the first substrate SUB1. The semiconductor layer, the conductive layer, and the insulating layer may constitute the circuit layer CCL and the display element layer of the display device 10, respectively.

The first substrate SUB1 may be an insulating substrate. The first substrate SUB1 may be made of an insulating material such as glass, quartz, or polymer resin. Also, the first substrate SUB1 may be a rigid substrate, but may also be a flexible substrate capable of being bent, folded, or rolled.

The first conductive layer may be disposed on the first substrate SUB1. The first conductive layer includes a lower metal layer BML, and the lower metal layer BML is disposed to overlap the active layer ACT1 of the first transistor T1. The lower metal layer BML may include a material that blocks light to prevent light from being incident on the active layer ACT1 of the first transistor.

The buffer layer BL may be disposed on the lower metal layer BML and the first substrate SUB1. The buffer layer BL is formed on the first substrate SUB1 to protect the transistors of the pixel PX from moisture penetrating through the first substrate SUB1, which is vulnerable to moisture permeation, and may perform a surface planarization function.

A semiconductor layer is disposed on the buffer layer BL. The semiconductor layer may include the active layer ACT1 of the first transistor T1. The active layer ACT1 may be disposed to partially overlap the gate electrode G1 of the second conductive layer, which will be described later.

Although the figure illustrates that one first transistor T1 is disposed in the sub-pixel SPn of the display device 10, the display device 10 is not limited thereto, and the display device 10 may include a larger number of transistors. .

The first gate insulating layer GI is disposed on the semiconductor layer and the buffer layer BL. The first gate insulating layer GI may serve as a gate insulating layer of the first transistor T1.

The second conductive layer is disposed on the first gate insulating layer GI. The second conductive layer may include the gate electrode G1 of the first transistor T1. The gate electrode G1 may be disposed to overlap the channel region of the active layer ACT1 in the third direction DR3 which is a thickness direction.

The first interlayer insulating layer IL1 is disposed on the second conductive layer. The first interlayer insulating layer IL1 may serve as an insulating layer between the second conductive layer and other layers disposed thereon and may protect the second conductive layer.

The third conductive layer is disposed on the first interlayer insulating layer IL1. The third conductive layer may include a first voltage line VDL, a second voltage line VSL, and a plurality of electrode patterns CDP1 and CDP2.

The first voltage line VDL is applied with a high potential voltage (or first power supply voltage) transmitted to the first electrode RME1, and the second voltage line VSL is applied with a low potential voltage transmitted to the second electrode RME2. A potential voltage (or second power supply voltage) may be applied. A portion of the first voltage line VDL may contact the active layer ACT1 of the first transistor T1 through a contact hole penetrating the first interlayer insulating layer IL1 and the first gate insulating layer GI. there is. The first voltage line VDL may serve as the first drain electrode D1 of the first transistor T1.

The first electrode pattern CDP1 may contact the active layer ACT1 of the first transistor T1 through a contact hole penetrating the first interlayer insulating layer IL1 and the first gate insulating layer GI. Also, the first electrode pattern CDP1 may contact the lower metal layer BML through another contact hole. The first electrode pattern CDP1 may serve as a first source electrode S1 of the first transistor T1.

The second electrode pattern CDP2 may be electrically connected to the first transistor T1 through the first electrode pattern CDP1. The first electrode pattern CDP1 and the second electrode pattern CDP2 may be connected to each other directly or through a pattern of another layer. The second electrode pattern CDP2 is also connected to the first electrode RME1, and the first transistor T1 may transfer the first power supply voltage applied from the first voltage line VDL to the first electrode RME1. .

The aforementioned buffer layer BL, the first gate insulating layer GI, and the first interlayer insulating layer IL1 may be formed of a plurality of inorganic layers that are alternately stacked. For example, the buffer layer BL, the first gate insulating layer GI, and the first interlayer insulating layer IL1 may include silicon oxide (SiO _x ), silicon nitride (SiN _x ), silicon acid It may be formed of a double layer in which an inorganic layer including at least one of silicon oxynitride (SiO _x N _y ) is stacked, or a multi-layer in which they are alternately stacked.

The second conductive layer and the third conductive layer are made of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd) and copper (Cu). It may be formed as a single layer or multiple layers made of any one or an alloy thereof. However, it is not limited thereto.

The via layer VIA is disposed on the third conductive layer. The via layer VIA may include an organic insulating material such as polyimide (PI) to perform a surface planarization function.

On the via layer VIA, a plurality of electrodes RME (RME1 and RME2), a plurality of first and second banks BNL1 and BNL2, a plurality of light emitting devices ED, and a plurality of connection electrodes CNE. ; CNE1, CNE2) are arranged. In addition, a plurality of insulating layers PAS1 , PAS2 , and PAS3 may be disposed on the via layer VIA.

The plurality of first banks BNL1 may be directly disposed on the via layer VIA. The first banks BNL1 may extend in the first direction DR1 and may be spaced apart from each other in the second direction DR2. A plurality of light emitting devices ED may be disposed between the spaced apart first banks BNL1 .

The first bank BNL1 may have a structure in which at least a portion of the first bank BNL1 protrudes from the top surface of the via layer VIA. The protruding portion of the first bank BNL1 may have an inclined side surface, and the light emitted from the light emitting device ED is reflected from the electrode RME disposed on the first bank BNL1 to form a via layer VIA. ) may be emitted in the upper direction of the

The plurality of electrodes RME are disposed for each sub-pixel SPn in a shape extending in one direction. The plurality of electrodes RME extend in the first direction DR1 and may be disposed over at least the light emitting area EMA and the sub area SA of the sub pixel SPn, and they extend in the second direction DR2. They can be spaced apart.

The first electrode RME1 and the second electrode RME2 are disposed to extend from the emission area EMA in the first direction DR1, and extend beyond the second bank BNL2 to the corresponding sub-pixel SPn and the first direction. It may be partially disposed in the subregion SA of another subpixel SPn adjacent to DR1. The first electrode RME1 and the second electrode RME2 of different sub-pixels SPn may be spaced apart from each other based on the separator ROP located in the sub-region SA of one sub-pixel SPn. .

The first electrode RME1 and the second electrode RME2 may be disposed on different first banks BNL1. The plurality of electrodes RME may be disposed on at least the inclined side of the first bank BNL1. Each of the electrodes RME may be disposed to cover at least one side surface of the first bank BNL1 to reflect light emitted from the light emitting device ED. In addition, the distance at which the plurality of electrodes RME are spaced apart in the second direction DR2 may be smaller than the distance between the first banks BNL1 . At least a portion of each electrode RME is directly disposed on the via layer VIA, so that they may be disposed on the same plane.

The first electrode RME1 and the second electrode RME2 may be connected to the third conductive layer through the first electrode contact hole CTD and the second electrode contact hole CTS, respectively. The first electrode RME1 may contact the second electrode pattern CDP2 through the first electrode contact hole CTD penetrating the via layer VIA therebelow. The second electrode RME2 may contact the second voltage line VSL through the second electrode contact hole CTS penetrating the via layer VIA therebelow.

The plurality of electrodes RME may be electrically connected to the light emitting element ED. Each of the electrodes RME may be connected to the light emitting element ED through connection electrodes CNE (CNE1, CNE2), which will be described later, and transmit an electric signal applied from a lower conductive layer to the light emitting element ED.

Each of the plurality of electrodes RME may include a conductive material having high reflectivity. For example, the electrode RME is a material with high reflectivity and includes a metal such as silver (Ag), copper (Cu), or aluminum (Al), or is made of aluminum (Al), nickel (Ni), lanthanum (La), or the like. It may be an alloy containing. However, it is not limited thereto, and each electrode RME may further include a transparent conductive material. For example, each electrode RME may include a material such as ITO, IZO, or ITZO. Each of the electrodes RME may have a structure in which a transparent conductive material and a metal layer having high reflectance are stacked one or more layers, or may be formed as one layer including these.

The first insulating layer PAS1 is disposed on the via layer VIA and the plurality of electrodes RME. The first insulating layer PAS1 is disposed to entirely cover the plurality of electrodes RME, and can protect them and at the same time insulate them from each other. In addition, the first insulating layer PAS1 may prevent the light emitting element ED disposed thereon from being damaged by direct contact with other members.

The first insulating layer PAS1 may include a plurality of contact portions CT1 and CT2 exposing portions of upper surfaces of the electrodes RME. The plurality of contact portions CT1 and CT2 pass through the first insulating layer PAS1, and connection electrodes CNEs described below may contact the exposed electrode RME through the contact portions CT1 and CT2.

The second bank BNL2 may be disposed on the first insulating layer PAS1. The second bank BNL2 may be arranged in a lattice pattern including portions extending in the first and second directions DR1 and DR2 on a plan view, and is arranged across the boundary of each sub-pixel SPn. Neighboring sub-pixels SPn may be distinguished. The second bank BNL2 may have a certain height. In some embodiments, the height of the upper surface of the second bank BNL2 may be higher than that of the first bank BNL1, and the thickness may be greater than that of the first bank BNL1. can be equal to or greater than

A plurality of light emitting devices ED may be disposed on the first insulating layer PAS1. The plurality of light emitting devices ED may be disposed on the electrodes RME spaced apart from each other in the second direction DR2 between the first banks BNL1 . The light emitting devices ED may be spaced apart from each other and aligned substantially parallel to each other along the first direction DR1 in which each electrode RME extends. The light emitting elements ED are disposed such that both ends are placed on different electrodes RME, and the direction in which each electrode RME extends and the direction in which the light emitting element ED extends are substantially perpendicular to each other. can

The light emitting devices ED may be electrically connected to the electrode RME by contacting the connection electrodes CNE (CNE1, CNE2). The light emitting elements ED may be electrically connected to the electrode RME and conductive layers under the via layer VIA through the connection electrodes CNE.

The second insulating layer PAS2 may be disposed on the plurality of light emitting elements ED. For example, the second insulating layer PAS2 is disposed to partially cover the outer surface of the light emitting element ED so as not to cover both sides or both ends of the light emitting element ED.

A plurality of connection electrodes CNE (CNE1, CNE2) and a third insulating layer PAS3 may be disposed on the second insulating layer PAS2.

A plurality of connection electrodes CNE are disposed on the light emitting elements ED and the electrode RME. In addition, the connection electrodes CNE are partially disposed on the second insulating layer PAS2 and may be insulated from each other by the other connection electrode CNE and the second insulating layer PAS2 and the third insulating layer PAS3. . The plurality of connection electrodes CNE may contact the light emitting element ED and the electrodes RME, respectively. The connection electrode CNE may directly contact the semiconductor layer exposed on both end surfaces of the light emitting element ED, and may directly contact the electrode RME through the contact portions CT1 and CT2 penetrating the first insulating layer PAS1. It may contact at least one of them. Both ends of the light emitting element ED may be electrically connected to the electrode RME through a plurality of connection electrodes CNE1 and CNE2.

The first connection electrode CNE1 has a shape extending in the first direction DR1 and may be disposed on the first electrode RME1. The first connection electrode CNE1 may contact the first electrode RME1 through the first contact portion CT1 and may contact the first ends of the light emitting devices ED. The second connection electrode CNE2 has a shape extending in the first direction DR1 and may be disposed on the second electrode RME2. The second connection electrode CNE2 may contact the second electrode RME2 through the second contact portion CT2 and may contact the second ends of the light emitting devices ED. The first connection electrode CNE1 and the second connection electrode CNE2 may transfer an electrical signal applied to the first electrode RME1 or the second electrode RME2 to one end of the light emitting element ED. Each connection electrode CNE may be spaced apart from each other in the second direction DR2 on a plan view. The first connection electrode CNE1 and the second connection electrode CNE2 may be spaced apart from each other by a predetermined interval so as not to be directly connected to each other.

The connection electrodes CNE may include a conductive material. For example, it may include ITO, IZO, ITZO, aluminum (Al), and the like. For example, the connection electrode CNE includes a transparent conductive material, and light emitted from the light emitting device ED may pass through the connection electrode CNE and proceed toward the electrodes RME. However, it is not limited thereto.

The third insulating layer PAS3 is disposed on the second connection electrode CNE2 and the second insulating layer PAS2. The third insulating layer PAS3 is disposed entirely on the second insulating layer PAS2 to cover the second connection electrode CNE2, and the first connection electrode CNE1 is disposed on the third insulating layer PAS3. can be placed in The third insulating layer PAS3 may mutually insulate the first connection electrode CNE1 from directly contacting the second connection electrode CNE2 .

In some embodiments, the third insulating layer PAS3 of the display substrate 11 may be omitted. Accordingly, each of the plurality of connection electrodes CNE may be directly disposed on the second insulating layer PAS2 and may be disposed on substantially the same layer as each other.

The encapsulation layer ENL may be disposed on the first connection electrode CNE1 and the third insulating layer PAS3. The encapsulation layer ENL may have a structure in which at least one insulating layer is stacked, and as illustrated in the drawing, the encapsulation layer ENL may have a structure in which an inorganic layer and an organic layer are sequentially stacked. The encapsulation layer ENL may serve to protect members disposed on the first substrate SUB1 against external environments.

Each of the aforementioned first insulating layer PAS1 , second insulating layer PAS2 , and third insulating layer PAS3 may include an inorganic insulating material or an organic insulating material. However, it is not limited thereto.

The color conversion substrate 13 is a second substrate SUB2 spaced apart from and opposed to the first substrate SUB1, and one surface of the second substrate SUB2 is disposed on one surface opposite to the first substrate SUB1. It may include a color filter layer (CFL; CFL1, CFL2, CFL3), a light blocking member (UBM), a third bank (BNL3), and color control structures (TPL, WCL1, WCL2).

The second substrate SUB2 may be made of a transparent material. The second substrate SUB2 may be a glass substrate or a plastic substrate. The second substrate SUB2 may include a plurality of light-blocking areas BA and light-transmitting areas TA. The light-blocking area BA may be an area in which first light-blocking members UBM, which will be described later, are disposed, and the light-transmitting area TA may be an area in which light is emitted to an area surrounded by the first light-blocking members UBM.

The first light blocking member UBM is one surface of the second substrate SUB2 and may be disposed on one surface opposite to the first substrate SUB1. The first light blocking member UBM may be formed in a lattice pattern to partially expose one surface of the second substrate SUB2. The first light blocking member UBM is disposed to cover the sub areas SA of each sub pixel SPn in addition to the second bank BNL2 of the display substrate 11 and to cover a portion of the emission area EMA. can be placed. An area where the first light blocking member UBM is not disposed may be a light transmission area TA where light is emitted through the color filter layers CFL1 , CFL2 , and CFL3 .

The first light blocking member UBM may include an organic material. The first light blocking member UBM can reduce color distortion due to external light reflection by absorbing external light. In one embodiment, the first light blocking member UBM may absorb all visible light wavelengths. The first light blocking member UBM may include a light absorbing material. For example, the first light blocking member UBM may be made of a material used as a black matrix.

The first to third color filter layers CFLs (CFL1, CFL2, and CFL3) are disposed on one surface of the second substrate SUB2 exposed by the first light blocking member UBM. The different color filter layers CFL1 , CFL2 , and CFL3 may be spaced apart from each other with the first light blocking member UBM interposed therebetween, but are not limited thereto.

The color filter layers CFL1 , CFL2 , and CFL3 include the first color filter layer CFL1 disposed on the first sub-pixel SP1 , the second color filter layer CFL2 disposed on the second sub-pixel SP2 , and the third sub-pixel (SP3) may include a third color filter layer (CFL3). The first to third color filter layers CFL1 , CFL2 , and CFL3 may be formed in an island pattern corresponding to the light emitting area EMA of the display substrate 11 or may be formed in a linear pattern extending in one direction.

In an exemplary embodiment, the first color filter layer CFL1 is a red color filter layer, the second color filter layer CFL2 is a green color filter layer, and the third color filter layer CFL3 is a blue color filter layer. Light emitted from the light emitting device ED may pass through the color control structures TPL, WCL1, and WCL2 and be emitted through the color filter layers CFL1, CFL2, and CFL3.

The first capping layer CPL1 may be disposed on the color filter layer CFL and the first light blocking member UBM. The first capping layer CPL1 may prevent the color filter layer CFL and the color control structures TPL, WCL1, and WCL2 from being damaged or contaminated by impurities such as moisture or air from the outside. In addition, the first capping layer CPL1 may prevent the material of the color control structures TPL, WCL1, and WCL2 from spreading to other components. The first capping layer CPL1 may be made of an inorganic material.

The third bank BNL3 may be disposed on one surface of the first capping layer CPL1. Similar to the second bank BNL2 of the display substrate 11 , the third bank BNL3 may be formed in a lattice pattern extending in the first and second directions DR1 and DR2 . The third bank BNL3 may distinguish areas where color control structures TPL, WCL1, and WCL2, which will be described later, are disposed.

The color control structures TPL, WCL1, and WCL2 may be disposed in an area surrounded by the third bank BNL3 on one surface of the first capping layer CPL1. The color control structures TPL, WCL1, and WCL2 may be formed in an island-like pattern disposed corresponding to the area surrounded by the third bank BNL3 or formed in a linear pattern extending in one direction.

In an embodiment in which the light emitting device ED of the display substrate 11 emits blue light of a third color, the color control structures TPL, WCL1, and WCL2 are the first wavelength conversion layer disposed on the first sub-pixel SP1. (WCL1), the second wavelength conversion layer WCL2 disposed on the second sub-pixel SP2, and the light-transmitting layer TPL disposed on the third sub-pixel SP3.

The first wavelength conversion layer WCL1 may include a first base resin BRS1 and a first wavelength conversion material WCP1 disposed in the first base resin BRS1. The second wavelength conversion layer WCL2 may include a second base resin BRS2 and a second wavelength conversion material WCP2 disposed in the second base resin BRS2. Each of the first wavelength conversion layer WCL1 and the second wavelength conversion layer WCL2 may further include a scattering material SCP included in each base resin, and the scattering material SCP may increase wavelength conversion efficiency.

The light transmission layer TPL may include a third base resin BRS3 and a scattering body SCP disposed in the third base resin BSR3. The light transmitting layer TPL transmits blue light of the third color incident from the light emitting device ED while maintaining the wavelength. The scattering object SCP of the light-transmitting layer TPL may serve to control an emission path of light emitted through the light-transmitting layer TPL. The light transmission layer TPL may not include a wavelength conversion material.

Scatterers (SCPs) may be metal oxide particles or organic particles. Titanium oxide (TiO2), zirconium oxide (ZrO2), aluminum oxide (Al2O3), indium oxide (In2O3), zinc oxide (ZnO), or tin oxide (SnO2) may be exemplified as the metal oxide, and the organic particles As the material, an acrylic resin or a urethane resin may be exemplified.

The first to third base resins BRS1 , BRS2 , and BRS3 may include a light-transmitting organic material. For example, the first to third base resins BRS1 , BRS2 , and BRS3 may include an epoxy-based resin, an acrylic-based resin, a cardo-based resin, or an imide-based resin. The first to third base resins BRS1 , BRS2 , and BRS3 may all be made of the same material, but are not limited thereto.

The first wavelength conversion material WCP1 may convert blue light of a third color into red light of a first color, and the second wavelength conversion material WCP2 may convert blue light of a third color into green light of a second color. there is. The first wavelength conversion material WCP1 and the second wavelength conversion material WCP2 may be quantum dots, quantum rods, or phosphors. The quantum dot may include a group IV nanocrystal, a group II-VI compound nanocrystal, a group III-V compound nanocrystal, a group IV-VI nanocrystal, or a combination thereof.

The light emitting device ED disposed on the first sub-pixel SP1 emits blue light of a third color, and the light may be incident to the first wavelength conversion layer WCL1. At least some of the light is incident on the scattering body SCP and the first wavelength conversion material WCP1 disposed in the first base resin BRS1, and the light is scattered and the wavelength is converted into red light so that the first capping layer ( It may be incident on the first color filter layer CFL1 through CPL1). The first color filter layer CFL1 may block transmission of light other than red light. Accordingly, red light may be emitted from the first sub-pixel SP1.

Similarly, light emitted from the light emitting element ED disposed in the second sub-pixel SP2 passes through the second wavelength conversion layer WCL2, the first capping layer CPL1, and the second color filter layer CFL2. It can emit green light.

The light emitting device ED disposed in the third sub-pixel SP3 emits blue light of a third color, and the light may be incident to the light-transmitting layer. Some of the light may pass through the third base resin BRS3 and be incident on the first capping layer CPL1 disposed thereon. The third color filter layer CFL3 may block transmission of light other than blue light. Accordingly, blue light may be emitted from the third sub-pixel SP3.

A second capping layer CPL2 is disposed on one surface of the color control structures TPL, WCL1, and WCL2 and one surface of the third bank BNL3. The second capping layer CPL2 may prevent the color control structures TPL, WCL1, and WCL2 from being damaged or contaminated by impurities such as moisture or air from the outside.

As the display device 10 includes the color conversion substrate 13 , selection of light sources used in the lighting units 130 and 150 of the inspection device 100 of the display device 10 may be important. As described above, the lighting units 130 and 150 of the inspection device 100 of the display device 10 include an ultraviolet light source, and the base portion 101 of the inspection device 100 of the display device 10 is provided with an ultraviolet light source. As the optical filter 105 is disposed, images IM1 and IM2 by UV light may be captured in the image capturing unit 110 . When the light used by the inspection device 100 of the display device 10 is light of a wavelength other than ultraviolet light, a color filter layer (CFL) disposed on the color conversion substrate 13 of the display device 10 to be inspected and color control It may be diffusely reflected or refracted by the structures TPL, WCL1, and WCL2. When the diffusely reflected light or the refracted light is incident on the image capture unit 110, distortion occurs in a captured image, and it may not be easy to determine defective particles. According to an embodiment, the inspection device 100 of the display device 10 may perform photography using ultraviolet light in order to minimize distortion of the captured image in consideration of the structure of the inspection target.

Referring back to FIG. 10 , the optical film 17 polarizes passing light. The optical film 17 may serve to reduce external light reflection. In one embodiment, the optical film 17 may be a polarizing film. The optical film may include a polarization layer and protective substrates disposed above and below the polarization layer. The polarization layer may include a polyvinyl alcohol film. The polarization layer may be stretched in one direction. An extension direction of the polarization layer may be an absorption axis, and a direction perpendicular thereto may be a transmission axis. The protective substrate may be disposed on one side and the other side of the polarization layer, respectively. The protective substrate may be made of a cellulose resin such as triacetyl cellulose, a polyester resin, etc., but is not limited thereto.

A protective film 19 may be disposed on the optical film 17 . It serves to protect the display substrate 11 and the color conversion substrate 13 of the protective film 19 . The protective film 19 may be made of a transparent material. The protective film 19 may be made of, for example, glass or plastic.

When the protective film 19 includes glass, the glass may be ultra thin glass (UTG) or thin glass. When the glass is made of an ultra-thin film or a thin film, it has a flexible property and may have a property that can be bent, bent, folded, or rolled. When the protective film 19 includes plastic, it may be more advantageous to exhibit flexible characteristics such as folding.

The coupling member 15 may couple the color conversion substrate 13 and the optical film 17 to each other. Also, the coupling member 15 may couple the optical film 17 and the protective film 19 to each other. The coupling member 15 may be disposed on the color conversion substrate 13 and be optically transparent.

14 is a schematic diagram of a light emitting device according to an embodiment.

Referring to FIG. 14 , the light emitting device ED may be a light emitting diode, and specifically, the light emitting device ED has a size of a nanometer to micrometer unit. and may be an inorganic light emitting diode made of an inorganic material. The light emitting device ED may be aligned between the two electrodes, where a polarity is formed when an electric field is formed in a specific direction between the two electrodes facing each other.

The light emitting device ED according to an exemplary embodiment may have a shape extending in one direction. The light emitting element ED may have a shape such as a cylinder, a rod, a wire, or a tube. However, the shape of the light emitting element ED is not limited thereto, and has a shape of a polygonal column such as a regular hexahedron, a rectangular parallelepiped, or a hexagonal prism, or a light emitting element that extends in one direction but has a partially inclined outer surface. ED) can have various forms.

The light emitting device ED may include a semiconductor layer doped with impurities of a certain conductivity type (eg, p-type or n-type). The semiconductor layer may emit light of a specific wavelength range by passing an electric signal applied from an external power source. The light emitting device ED may include a first semiconductor layer 31 , a second semiconductor layer 32 , a light emitting layer 36 , an electrode layer 37 , and an insulating layer 38 .

The first semiconductor layer 31 may be an n-type semiconductor. The first semiconductor layer 31 may include a semiconductor material having a chemical formula of AlxGayIn1-x-yN (0≤x≤1, 0≤y≤1, 0≤x+y≤1). For example, the first semiconductor layer 31 may be any one or more of n-type doped AlGaInN, GaN, AlGaN, InGaN, AlN, and InN. The n-type dopant doped in the first semiconductor layer 31 may be Si, Ge, or Sn.

The second semiconductor layer 32 is disposed on the first semiconductor layer 31 with the light emitting layer 36 interposed therebetween. The second semiconductor layer 32 may be a p-type semiconductor, and the second semiconductor layer 32 is AlxGayIn1-x-yN (0≤x≤1,0≤y≤1, 0≤x+y≤1) It may include a semiconductor material having a chemical formula. For example, the second semiconductor layer 32 may be any one or more of p-type doped AlGaInN, GaN, AlGaN, InGaN, AlN, and InN. The p-type dopant doped in the second semiconductor layer 32 may be Mg, Zn, Ca, Se, Ba, or the like.

Meanwhile, in the drawings, the first semiconductor layer 31 and the second semiconductor layer 32 are configured as one layer, but are not limited thereto. Depending on the material of the light emitting layer 36, the first semiconductor layer 31 and the second semiconductor layer 32 may further include a greater number of layers, for example, a clad layer or a Tensile Strain Barrier Reducing (TSBR) layer. may be

The light emitting layer 36 is disposed between the first semiconductor layer 31 and the second semiconductor layer 32 . The light emitting layer 36 may include a material having a single or multi-quantum well structure. When the light emitting layer 36 includes a material having a multi-quantum well structure, a plurality of quantum layers and well layers may be alternately stacked. The light emitting layer 36 may emit light by combining electron-hole pairs according to electric signals applied through the first semiconductor layer 31 and the second semiconductor layer 32 . The light emitting layer 36 may include a material such as AlGaN or AlGaInN. In particular, when the light emitting layer 36 has a multi-quantum well structure in which quantum layers and well layers are alternately stacked, the quantum layer may include AlGaN or AlGaInN, and the well layer may include GaN or AlInN.

The light emitting layer 36 may have a structure in which a semiconductor material having a high band gap energy and a semiconductor material having a low band gap energy are alternately stacked, and different groups 3 to 5 may be formed according to the wavelength range of light emitted. It may also contain semiconductor materials. Light emitted from the light emitting layer 36 is not limited to light in a blue wavelength band, and may emit red and green wavelength bands in some cases.

The electrode layer 37 may be an Ohmic connection electrode. However, it is not limited thereto, and may be a Schottky connection electrode. The light emitting device ED may include at least one electrode layer 37 . The light emitting element ED may include one or more electrode layers 37, but is not limited thereto and the electrode layer 37 may be omitted.

The electrode layer 37 may reduce resistance between the light emitting element ED and the electrode or connection electrode when the light emitting element ED is electrically connected to the electrode or connection electrode in the display device 10 . The electrode layer 37 may include a conductive metal. For example, the electrode layer 37 may include at least one of aluminum (Al), titanium (Ti), indium (In), gold (Au), silver (Ag), ITO, IZO, and ITZO.

The insulating film 38 is disposed to surround outer surfaces of the plurality of semiconductor layers and electrode layers described above. For example, the insulating film 38 may be disposed to surround at least the outer surface of the light emitting layer 36, but both ends of the light emitting element ED in the longitudinal direction may be exposed. In addition, the insulating layer 38 may be formed to have a rounded upper surface in cross-section in a region adjacent to at least one end of the light emitting element ED.

The insulating film 38 is made of materials having insulating properties, for example, silicon oxide (SiO _x ), silicon nitride (SiN _x ), silicon oxynitride (SiO _x N _y ), aluminum nitride (AlN _x ), aluminum oxide ( AlO _x ) and the like. In the drawing, it is illustrated that the insulating film 38 is formed of a single layer, but is not limited thereto, and in some embodiments, the insulating film 38 may be formed of a multi-layer structure in which a plurality of layers are stacked.

The insulating film 38 may serve to protect the members. The insulating film 38 may prevent an electrical short circuit that may occur in the light emitting layer 36 when it directly contacts an electrode through which an electric signal is transmitted to the light emitting element ED. In addition, the insulating layer 38 may prevent a decrease in light emitting efficiency of the light emitting device ED.

In addition, the outer surface of the insulating film 38 may be surface-treated. The light emitting device ED may be sprayed and aligned on the electrode in a dispersed state in a predetermined ink. Here, in order to maintain a state in which the light emitting elements ED are dispersed and not aggregated with other adjacent light emitting elements ED in the ink, the surface of the insulating layer 38 may be treated to be hydrophobic or hydrophilic.

Hereinafter, a method of inspecting the display apparatus 10 using the inspection apparatus 100 of the display apparatus 10 will be described with further reference to other drawings.

15 is a flowchart illustrating a method of inspecting a display device according to an exemplary embodiment.

Referring to FIG. 15 , a method for inspecting a display device according to an exemplary embodiment uses lighting units 130 and 150 of the inspection device 100 and an image capture unit 110 of the display device 10 to examine a subject to be inspected. It may include obtaining video images for each floor (S10), acquiring information on bad candidates from the acquired video images (S20), and applying pass/fail determination to the bad candidates (S30).

The inspection method of the display device may be performed by the inspection device 100 of the display device 10 described above with reference to FIGS. 1 to 9 . In step S10 of obtaining a video image, while irradiating light from the lighting units 130 and 150 , the image capturing unit 110 may obtain a video image for each layer of the inspection target through the mirror imaging system 111 . Subsequently, the step of obtaining information on bad candidates (S20) and the step of applying the pass/fail decision (S30) may be performed by an algorithm performed by the image processing unit 180, respectively. Hereinafter, operations and algorithms of the inspection device 100 of the display device 10 performed in each step will be described in detail.

16 is a flowchart illustrating in detail a video image acquisition step in a method for inspecting a display device according to an exemplary embodiment.

Referring to FIG. 16 , in the inspection method of the display device 10 according to an embodiment, acquiring a video image (S10) includes setting an initial focus position (S11) and photographing an inspection target under a first lighting condition. (S12) obtaining a first video image (IM1) by taking a photo of the inspection target under a second lighting condition (S13), and determining whether an additional video image needs to be acquired (S13). (S15) may be included. When it is necessary to acquire an additional video image according to whether it is necessary to acquire an additional video image, the system controller 113 of the video capturing unit 110 adjusts the mirror array MA to control the focal position, and then the video image acquisition step ( S12, S13) are repeated. Otherwise, when video image acquisition is not required, information acquisition of bad candidates (S20) may be performed.

The step of setting the initial focus position (S11) may be performed to obtain an initial video image of the display device 10 to be inspected and to set a standard for a focus movement direction. In the display device 10 composed of a plurality of layers, at least one video image may be captured for each layer, and the focus of the image capture unit 110 moves in one direction from an initial focus position to obtain a plurality of video images. can Since the position of the defective particle P to be detected cannot be known in the inspection target, the inspection method of the display device 10 may obtain a video image by moving the focus along the direction in which the plurality of layers are stacked. As the initial setting value, the system controller 113 may set the initial focus position of the image capturing unit 110 .

As described above, the image capture unit 110 of the inspection device 100 of the display device 10 obtains an image by selectively receiving only the light reflected by the object OB located at the set focus among the reflected lights. can do. The focus or focus position set by the image capture unit 110 may be the position of the object OB that reflects the light emitted from the lighting units 130 and 150 .

Here, the initial focus position may be set on one side or the other side of the display device 10 in a direction in which a plurality of layers are stacked. For example, the one surface of the display device 10 may be the upper surface of the protective film 19 as the uppermost layer, and the other surface may be the lower surface of the display substrate 11 as the lowermost layer. According to an embodiment, in the method of inspecting the display device 10, setting the initial focus position (S11) controls the mirror array MA of the image photographing unit 110 to focus on the protective film 19, which is the uppermost layer. ), or a step of setting on the surface. The image photographing unit 110 may acquire a plurality of image images for each focal point while moving the focal point from the surface of the protective film 19 to the direction in which the display substrate 11 is disposed. In an embodiment in which the initial focus position of the image capture unit 110 is set on the surface of the protective film 19, the system controller 113 calculates the initial focus position from the distance to the inspection target measured by the laser unit 190. can be set by However, it is not limited thereto, and the system control unit 113 may set the initial focus position through a series of algorithms.

Next, when the initial focus position is set, a first video image IM1 is acquired by photographing the inspection target under a first lighting condition (S12). The first lighting condition is a state in which the first lighting unit 130 irradiates the first light L1, and the image capturing unit 110 captures the first video image IM1 from the reflected first light L1'. can be obtained The first video image IM1 may be a video image taken from coaxial illumination. Under the first lighting condition, the lighting units 151 and 153 of the second lighting unit 150 may be in an off state.

Subsequently, when the first video image IM1 is acquired under the first lighting condition, the first lighting unit 130 is turned off, and the inspection target is photographed under the second lighting condition to obtain a second video image IM2 (S13). )do. The second lighting condition is a state in which the second lighting unit 150 radiates the second light L2, and the image capture unit 110 captures the second video image IM2 from the reflected second light L2'. can be obtained The second video image IM2 may be a video image taken from quasi-coaxial illumination.

As described above, the first video image IM1 and the second video image IM2 may have different shapes or brightness with respect to the same shape according to the incident angle of the irradiated light. When a plurality of video images of different shapes or brightness are acquired at a specific focal position, it is possible to accurately determine whether the particles found in the image are defective particles or distorted images due to light reflection.

When the image capture unit 110 acquires the video images IM1 and IM2, the image processing unit 180 may receive the video images IM1 and IM2 and focus position information set by the system controller 113. The image processing unit 180 may select the obtained image images IM1 and IM2 in a subsequent step, and may determine whether an additional image image acquisition is necessary through a series of algorithms.

Next, when video images are acquired under the first lighting condition and the second lighting condition, a step of determining whether additional video images need to be acquired is performed (S15). Whether additional video images need to be acquired may be determined based on the video images acquired by the video capturing unit 110 and the focal position set by the system controller 113 . For example, when moving along the moving direction of the focus based on the previous focus position set by the system controller 113, if the moved focus position deviates from the inspection target, the image processing unit 180 provides an additional image. It may be determined that image acquisition is not required. Otherwise, if the focus is located within the inspection target when the focus is moved, or if additional imaging of the defective particles (P) found in the previously obtained video image is required, the image processing unit 180 acquires an additional video image. It can be judged as necessary. In this step, it may be determined whether an additional video image needs to be photographed through the distance between the focal position set by the system controller 113 and the specific target measured by the laser unit 190 .

If it is necessary to acquire an additional video image, a step of controlling the focal position by adjusting the mirror array MA of the image capture unit 110 (S17) may be performed. In the step of controlling the focus position (S17), the image processing unit 180 provides the system controller 113 with information indicating that additional video image acquisition is required, and the system controller 113 sets the focus position to be constant based on the information. An inclination angle of the mirror array MA may be adjusted so as to be moved at intervals.

The distance between the focal points moved by the system controller 113 may be determined according to a preset value. For example, the movement interval may be set in advance so that the focus is set at a position where the defective particles P are likely to exist according to the thickness of the inspection target, the total thickness of the display device 10, or the thickness of each layer. . However, it is not limited thereto, and the distance between the focal points moved by the system controller 113 may be controlled based on video images obtained from the previous focal points provided by the image processing unit 180 .

In particular, among the defective particles P of the display device 10, the defective particles P located on the top surface or the bottom surface of the bottom layer may be particles adsorbed from the outside. These defective particles P are elements that do not affect the determination of good or bad quality of the display device 10, and may be defects that can be easily removed through a surface cleaning process or the like. That is, the defective particles P located inside the display device 10, the inside of each layer, or the interface between each layer may determine whether the display device 10 is defective or needs repair. Intrinsic defective particles that affect the outermost layer and located on the surface of the uppermost layer or the lowermost layer may be caustic defective particles that can be removed through a simple cleaning process.

Among the defective particles P, defective particles belonging to caustic defective particles can be easily identified based on their positions. For example, when the initial focus position is located on the uppermost layer surface, defective particles P photographed within a certain interval therefrom are likely to be false defective particles. On the other hand, when the focus is located inside the uppermost layer away from the initial focus position, defective particles P photographed thereafter are highly likely to be intrinsic defective particles. In the step of shifting the focus for acquiring additional video images, the video image acquisition for fake bad particles and the video image acquisition for true bad particles can be distinguished by setting different focus movement intervals according to the position of the previous focus.

17 is a flowchart illustrating in detail the step of controlling the focus position in the video image acquisition step of FIG. 16 .

Referring to FIG. 17 in addition to FIG. 16, according to an embodiment, in the step of controlling the focus position by adjusting the mirror array MA of the image capturing unit 110 (S17), the previous focus position is located on the outermost layer surface. (S171), and moving the focus at a first interval (S173) or moving the focus at a second interval (S175) according to the previous focus position.

As described above, there is a high probability that caustic defective particles caused by dust adsorbed from the outside are found on the outermost surface of the display device 10, particularly on the uppermost surface. When the previous focal position is located adjacent to the surface of the outermost layer, defective particles P found in video images acquired at the corresponding focal point may be identified as pseudo-defective particles. Accordingly, if the previous focus position is located on the surface of the outermost layer, the steps of acquiring video images under the first and second lighting conditions (S12 and S13) may be performed by moving the focus position at a first interval.

On the other hand, when the previous focal position is located inside the display device 10 at a position other than the surface of the outermost layer, defective particles P found in video images acquired at the focal point are identified as intrinsic defective particles. It can be. Accordingly, if the previous focus position is located on the inside of the outermost layer instead of the surface, the steps of moving the focus position at a second interval to acquire video images under the first and second lighting conditions (S12 and S13) are performed. can

For example, the caustic defective particles may have a smaller size than the intrinsic defective particles, and the first interval may be smaller than the second interval. The first interval may have a range of 0.1 μm to 10 μm, and the second interval may have a range of 10 μm to 50 μm, or about 20 μm. If the defective particles have a certain level of size, it can be predicted that similar defective particles will not be found within a certain focal interval from the video image in which the defective particles are found. The efficiency of the focus movement step may be improved by appropriately adjusting the distance between the moving focus positions according to the size of the defective particles. In particular, by moving the focus at different intervals according to the position of the previous focal point, it may be determined whether the interval between the moved focal points is the first interval or the second interval in the video image obtained from the corresponding focal point. From this, there is an advantage in that it is possible to determine whether the video image acquired at the focal point is an image for identifying caustic defective particles or an image for identifying caustic defective particles.

The step of checking whether the previous focus position is located on the surface of the outermost layer may be performed by the image processing unit 180 and the system controller 113 . The system control unit 113 may store information on the previous focus position, and the image processing unit 180 may store information about the obtained video image, the distance to the inspection target through the laser unit 190, and the like. . When the focus is moved based on the focus position stored in the system control unit 113, since the distance between the focus position and the inspection target is not included, the step of checking the previous focus position in consideration of the information stored in the image processing unit 180 can be done In addition, the step of checking whether the previous focus position is located on the outermost layer surface may be performed as a step of checking whether the previous focus position is located inside the display device 10 in the opposite sense.

As described above, the image capture unit 110 adjusts the focus position and acquires a plurality of video images according to the first lighting condition and the second lighting condition. When the focus position is moved at regular intervals and the focus position is set outside the inspection target or the display device 10, a different result may be determined in step S15 to determine whether an additional video image needs to be acquired. That is, when additional video image acquisition is not required, the image processing unit 180 may perform step S20 of obtaining information on bad candidates from the acquired video image.

18 is a flowchart illustrating in detail an information acquisition step of bad candidates in a method for inspecting a display device according to an exemplary embodiment. 19 is a flowchart illustrating in detail a step of selecting bad candidates in a method for inspecting a display device according to an exemplary embodiment.

Referring to FIGS. 18 and 19 in addition to FIG. 15 , obtaining information on bad candidates (S20) includes selecting bad candidates from acquired video images (S21) and extracting location information from the bad candidates. Step S22 may be included. Obtaining information on bad candidates ( S20 ) may be performed in the image processing unit 180 in which image images are stored.

In the step of selecting bad candidates from the obtained video images (S21), it is checked whether or not bad particles P are found among the acquired video images (S211), and images in which bad particles P are found and images where there are no bad particles P are found. It may include the step of dividing into . This is a primary screening step, by selecting images in which no defective particles P are found, so that among the video images in which the defective particles P are found, the defective particles P that can affect the pass/fail determination of the display device 10 ) can be performed before secondary screening.

When the image images in which the defective particles P are found are selected, geometric information of the defective particles may be extracted from the image images in which the defective particles are found (S212). The geometrical information of the detected defective particles P may be information such as the size of the defective particles P and a difference in contrast between the first and second image images IM1 and IM2. In this step, the geometrical information of the defective particles P found in each video image may be a basis for determining whether the corresponding defective particles P can affect the pass/fail decision.

Subsequently, a step S213 of determining intrinsic defective particles based on the geometrical information of the defective particles P is performed. All of the defective particles P do not become intrinsic defective particles, and defective particles P whose geometrical information of the defective particles P exceeds a critical value may become intrinsic defective particles. A predetermined value may be used as a criterion for the geometrical information of the defective particles P. In the image processing unit 180, a threshold value set in advance by a user may be stored, and the step of comparing geometric information and threshold values of defective particles P extracted from video images and determining them as genuine defective particles may include: can be performed

However, it is not limited thereto, and the preset value may not be stored, or the threshold value may need to be modified even if it is stored. For example, in the step of determining the intrinsic bad particles, comparing the video images in which the bad particles P are found with other video images, and images acquired at the focal positions before and after the corresponding video images. A step of comparing with images may be further performed. A threshold value, which is a criterion for determining an intrinsic defective particle, may be set from the defective particles P found through these steps and the geometrical information of the extracted defective particles P. In this case, since the criterion for the threshold value is not set in the image processing unit 180 and the threshold value is set simultaneously with video image acquisition, the criterion for determining pass/fail of the display device 10 is reset to the criterion optimized for the corresponding manufacturing process. It can be.

Next, when bad candidates are selected, a step of extracting location information from the bad candidates (S22) is performed. The location information of the defective candidates may be information about a layer where the defective particle P of the display device 10 is located, information about coordinates of the defective particle P in the corresponding layer, and the like. From this, all information on the defective particles P, which is the basis for determining the quality of the display device 10, can be collected. Although not shown in the drawings, caustic defective particles existing on the surface of the outermost layer may also be identified from the location information of the defective particles P.

Finally, a pass/fail decision application step (S30) is performed on bad candidates. In the application of the good/defective decision, when there are no bad candidates, it is judged as a good product. In addition, it is possible to determine good products through a cleaning process or the like for caustic defective candidates present in the outermost layer of the display device 10 . When defective candidates in which the defective particles P exist inside the display device 10 are found, a step of determining whether they can be repaired or are subject to discarding may be performed.

20 is a flowchart illustrating in detail a step of applying pass/fail determination to bad candidates in a method for inspecting a display device according to an exemplary embodiment.

Referring to FIG. 20 in addition to FIG. 15 , whether or not the display device 10 can be repaired may vary according to location information of defective particles. Among the plurality of layers included in the display device 10, the protective film 19 located on the uppermost layer can be easily attached or detached. If the defective particles P of the defective candidates are located only on the protective film 19, this can be repaired by replacing only the protective film 19. On the other hand, if the defective particles P of the defective candidates are located inside a layer other than the protective film 19, it is not easy to repair.

According to an embodiment, the step of applying pass/fail judgment to the bad candidates (S30) includes a step of checking whether the bad candidates can be repaired (S31), and the step is based on the location information of the bad particles P, That is, it may include determining whether the display device 10 can be repaired (S33) or scrapping (S35). Determination of repairability or discarding may be based on location information of defective particles P as described above.

Through the above process, it is possible to perform inspection of the display device 10 composed of a plurality of layers, in particular, inspection of appearance defects. The inspection device 100 of the display device 10 may acquire video images of a plurality of layers by moving the focus instead of directly moving them, and may extract information on bad particles P from the acquired video images. there is. Based on the information of the defective particles (P), it is possible to determine whether or not repair is possible together with judgment of good or bad.

Meanwhile, the inspection device 100 of the display device 10 may further include another device for determining caustic defects due to defective particles present on the surface of the outermost layer. According to one embodiment, the inspection device 100 of the display device 10 emits light from the side of the display device 10 to be inspected in addition to the first lighting unit 130 and the second lighting unit 150. 3 lighting units ('170' in FIG. 20) may be further included.

21 is a schematic diagram illustrating an operation of a third lighting unit in an inspection device of a display device 10 according to another embodiment. FIG. 22 is a flowchart illustrating in detail a video image acquisition step in the inspection method using the inspection device of the display device 10 of FIG. 21 .

Referring to FIGS. 21 and 22 in conjunction with FIG. 1 , the inspection device 100_1 of the display device 10 according to an embodiment is the same axis on which the image capturing unit 110 and the display device 10 to be inspected are disposed. It may further include a third lighting unit 170 radiating third light L3 in a direction perpendicular to the above. The third lighting unit 170 emits third light (L3) in a direction perpendicular to the same axis as the image capturing unit 110 on the surface of the outermost layer of the display device 10, that is, in a direction parallel to the surface of the display device 10. ) can be investigated. When the third light L3 is reflected or refracted on the surface of the display device 10 and enters the image capturing unit 110 through the light receiving unit 103, the image capturing unit 110 is reflected or refracted on the surface of the display device 10. A third video image may be obtained. Accordingly, in the video image acquisition step (S10), obtaining a third video image by photographing the inspection target under the third lighting condition using the third lighting unit 170 following the first lighting condition and the second lighting condition. (S14) may be further performed.

As described above, there is a high probability that the defective particles P located on the surface of the outermost layer of the display device 10 are caustic defective particles that are easily removed through a cleaning process or the like. The third light L3 irradiated in parallel to the surface of the display device 10 is highly likely to cause optical interference with the defective particles P adsorbed on the surface, and the third light L3 is the reflected light ( The third video image sensed by L3') may represent false bad particles. According to the present embodiment, the inspection device 100 of the display device 10 can easily detect surface adsorbed particles that are caustic defective particles, and in the step of determining caustic defective particles, the third video image captured under the third lighting conditions. It has the advantage of being able to make a clearer judgment through

Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art to which the present invention pertains can be implemented in other specific forms without changing the technical spirit or essential features of the present invention. you will be able to understand Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting.

10: display device
100: Inspection device of display device
110: video recording unit
111: mirror imaging system
113: system control unit
130: first lighting unit
150: second lighting unit
170: third lighting unit
180: image processing unit

Claims (20)

Set a focus on a display device including a plurality of layers, acquire a plurality of first video images from the first light reflected on the focal point under a first lighting condition in which the first light is irradiated, and obtaining a plurality of second video images from the second light reflected on the focal point under a second lighting condition in which two lights are irradiated;
obtaining information on bad candidates in which bad particles of the display device are found from the obtained video images; and
Applying a pass/fail decision to the bad candidates;
The image capture unit includes a mirror array in which a plurality of mirrors are tilted with an inclination angle, and a system control unit controlling the inclination angles of the mirrors,
The position of the focal point is set according to the inclination angle of the mirrors,
Acquiring the video image further includes determining whether additional video image acquisition is required,
If it is necessary to acquire the additional video image,
The system control unit of the image photographing unit controls inclination angles of the mirrors to move the focal point in the direction in which the layers of the display device are stacked, and captures the first video image and the second video image at different focal positions. A method of inspecting a display device to further obtain. delete According to claim 1,
The system control unit of the image capture unit moves the focal point at a first interval or a second interval based on the position of the previous focal point;
The first interval is smaller than the second interval. According to claim 3,
The system control unit of the image capturing unit moves the focal point by the first interval when the position of the previous focal point is located on the surface of the outermost layer of the display device,
moving the focal point by the second interval when the position of the previous focal point is located inside the display device. According to claim 1,
In the step of determining whether the additional video image acquisition is necessary,
and acquiring information of the defective candidates by determining that the acquisition of the additional video image is not necessary when the location where the focus is moved is located outside the display device. According to claim 1,
The obtaining of information on the bad candidates may include selecting bad candidates from among the obtained video images; and
and extracting location information of the defective candidates in the display device from the defective candidates. According to claim 6,
The selecting of the bad candidates may include checking whether the bad particles are found among the obtained video images;
extracting geometric information of the defective particle from the video images in which the defective particle is found; and
and determining intrinsic defective particles based on the geometrical information of the defective particles. According to claim 7,
Determining the intrinsic defective particles based on the geometric information of the defective particles may include comparing the geometric information of the defective particles with geometric information of defective particles found in a plurality of other video images to set a threshold value for determining defects. ; and
and determining the defective particle as the intrinsic defective particle by comparing the threshold value with the geometrical information of the defective particle. According to claim 6,
The applying of the pass/fail decision to the defective candidates includes determining whether the display device can be repaired or discarded based on location information of the defective candidates. According to claim 9,
In the step of applying a pass/fail decision to the defective candidates, if the location of the defective particle of the defective candidates is located on the top layer of the display device, it is determined that the repairable decision is made. According to claim 1,
The image capture unit is arranged to lie on the same axis as the display device,
The first light is irradiated to the display device in a direction parallel to the axis,
The second light is radiated to the display device in a direction inclined to the axis. According to claim 11,
The first light is irradiated in a direction perpendicular to the axis and propagated in the same direction as the axis by a light path conversion unit disposed on the axis. According to claim 11,
In the acquiring of the video image, the inspection of the display device further comprising the step of irradiating third light emitted in a direction perpendicular to the axis and obtaining a third video image from the third light reflected from the focal point. method. According to claim 13,
and determining that the defective particles found in the third video image are pseudo-defective particles in the step of applying a pass/fail decision to the defective candidates. According to claim 11,
The first light and the second light are ultraviolet light,
The method of inspecting a display device of claim 1 , wherein the first light and the second light reflected from the focal point are incident to the image photographing unit through an optical filter that selectively transmits ultraviolet light. In the inspection apparatus of a display device including a plurality of layers,
an image capture unit arranged on the same axis as the display device to acquire video images of the display device;
a first lighting unit emitting a first light to the display device in the same direction as the axis, and a second lighting unit emitting a second light in a direction inclined to the axis; and
And an image processing unit that obtains information of bad candidates in which bad particles of the display device are found from the video images acquired by the image capturing unit,
The image photographing unit includes a mirror imaging system including a mirror array in which a plurality of mirrors are tilted with an inclination angle, and a sensor unit that senses light reflected from the mirrors to obtain an image image, and a system control unit that adjusts the inclination angles of the mirrors. including,
The system controller adjusts inclination angles of the mirrors to set a focus on the display device, and the sensor unit obtains a first video image and a second video image from the first light or the second light reflected at the focus, respectively. do,
In the image photographing unit, the system controller controls inclination angles of the mirrors to move the focal point in the direction in which the layers of the display device are stacked;
An inspection device of a display device further acquiring the first video image and the second video image at different focal positions. delete According to claim 16,
wherein the image processing unit selects the defective candidates from among the video images acquired by the image capture unit, and extracts positional information of the defective candidates in the display device from the defective candidates. According to claim 18,
wherein the image processing unit determines whether or not the defective particle is found among the acquired image images and extracts geometrical information of the defective particle from the image images in which the defective particle is found. According to claim 16,
Each of the first lighting unit and the second lighting unit irradiates ultraviolet light, and further comprises an optical filter disposed between the image photographing unit and the display device to selectively transmit ultraviolet light.

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