Method of manufacturing a display device

Abstract

A manufacturing method of a display device is provided. The manufacturing method of the display device is a method of manufacturing a display device by a step of assembling a first unit and a second unit using a bonding unit, the method including, before the step of assembling, a surface inspection step including a process of irradiating light to each surface of an upper surface and a lower surface of the bonding unit and collecting light reflected by the each surface, a step of confirming a surface defect of the each surface, and a repair step of removing the surface defect.

Description

TECHNICAL FIELD

[0001] The present application relates to a manufacturing method of a display device, and more particularly, to a method of finding a surface defect and repairing the surface defect before manufacturing of a display device is completed. BACKGROUND

[0002] Recently, as multimedia is developed, importance of a display device is increasing. In response to this, a liquid crystal display device, a plasma display device, an organic light emitting display device, and the like flat panel display devices are being commercialized.

[0003] A display device is manufactured through a process of assembling a plurality of cells using an adhesive cell. Generally, a display device is tested when it is shipped. In an individual case, unevenness of brightness of a screen of the display device can be found through the test.

[0004] The unevenness of brightness of the screen can be caused by a surface defect occurring on a surface of the adhesive cell. However, when the surface defect occurring on the surface of the adhesive cell is found at the step of the test, a high cost and time are required until the surface defect is repaired. SUMMARY

[0005] The present application relates to a manufacturing method of a display device, and more particularly, to a method of finding a surface defect and repairing the surface defect before manufacturing of a display device is completed.

[0006] The present application is not limited to the above-mentioned problems, and other technical problems not mentioned can be clearly understood by those skilled in the art through the following description.

[0007] An embodiment of the present application for solving the problems relates to a manufacturing method of a display device, which is a method of manufacturing a display device through a step of assembling a first cell and a second cell using an adhesive cell, the method including, before the step of assembling, a surface inspection step including a process of irradiating light to each surface of an upper surface and a lower surface of the adhesive cell and collecting light reflected by the each surface, a step of confirming a surface defect of the each surface, and a repair step of removing the surface defect.

[0008] The first cell can be a display panel, the second cell can be a window substrate, and the adhesive cell can include an optically clear adhesive (OCA).

[0009] In the surface inspection step, the light can have a wavelength of 495 nm to 600 nm.

[0010] In the surface inspection step, the light can be slit light passing through a slit to form a scan line in one direction on the each surface.

[0011] In the surface inspection step, the direction in which the scan line moves can be a direction intersecting the direction in which the scan line extends.

[0012] In the surface inspection step, the light can be simultaneously irradiated to the surfaces of the bonding unit.

[0013] The light irradiated to at least one of the surfaces of the bonding unit, a first surface facing the upper surface, and a second surface facing the lower surface can not be formed on a virtual straight line.

[0014] In the surface inspection step, the light can be irradiated to the surfaces of the bonding unit in a state in which the first unit, the second unit, and the bonding unit are separated by a predetermined interval.

[0015] The repairing step can include at least one of a process of cleaning, mechanical masking, and chemical polishing of the surface in which the surface defect is confirmed.

[0016] The surface inspection step can include a step of confirming a defect position, and a step of irradiating the light to the surfaces of the bonding unit and collecting the light reflected by the surfaces.

[0017] Details of other embodiments are included in the detailed description and the drawings.

[0018] (EFFECT OF INVENTION)

[0019] According to the embodiments of the present invention, a surface defect can be inspected and repaired before a plurality of units of a display device are assembled using a bonding unit.

[0020] Thus, cost and time required for manufacturing the display device can be saved.

[0021] Effects related to the embodiments are not limited to the above examples, and more effects are included in the specification. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 FIG. 1 is a perspective view of a display device according to an embodiment.

[0023] Figure 2 FIG. 2 is an exploded perspective view of the display device of FIG. 1. Figure 1

[0024] Figure 3 FIG. 4 is a schematic cross-sectional view of the display device of FIG. 1. Figure 1

[0025] Figure 4 ​​is an algorithmic sequence diagram representing part of the process of the manufacturing method of a display device to which an embodiment of the present invention relates.

[0026] Figures 5 to 8 is a perspective view representing part of the process of the surface defect inspection step of Figure 4

[0027] Figure 9 and Figure 10 is a cross-sectional view representing the process of Figure 5

[0028] Figure 11 is a chart representing part of the results measured by the process of Figure 5

[0029] Figure 12 is a final computer simulation result image of a display device schematically representing the process of Figures 5 to 8

[0030] Figure 13 is a cross-sectional view for illustrating the error correction step of Figure 4

[0031] Figure 14 is a chart for illustrating the error correction step of Figure 4

[0032] Figure 15 is a sequence diagram representing the detailed steps of the repair step of Figure 4

[0033] Figure 16 is an algorithmic sequence diagram representing part of the process of the manufacturing method of a display device to which another embodiment of the present invention relates.

[0034] Figure 17 is a cross-sectional view representing part of the process of the surface defect inspection step in the manufacturing method of a display device to which another embodiment relates.

[0035] Figure 18 is a schematic cross-sectional view of a display device to which yet another embodiment relates.

[0036] Figure 19 is a cross-sectional view representing part of the process of the surface defect inspection step in the manufacturing method of a display device of Figure 18

[0037] Figure 20 is an algorithmic sequence diagram representing part of the process of the manufacturing method of a display device to which yet another embodiment of the present invention relates. DETAILED DESCRIPTION

[0038] Reference is made to the accompanying drawings that form a part of this disclosure and which illustrate far better than words the general principles of the application. Figure 1 ​​​​​​​​As will become clear from the detailed description of the embodiments described below, the advantages and features of the invention, as well as the methods for achieving these advantages and features, will become apparent. However, the invention is not limited to the embodiments disclosed below and may be embodied in various different ways. The embodiments are provided only to make the disclosure of the invention complete and to fully inform those skilled in the art of the scope of the invention, and the invention is defined only by the scope of the claims.

[0039] The phrase "on" an element or layer refers not only to its direct placement on top of other elements or layers, but also to its presence with other layers or elements sandwiched between them. Throughout this specification, the same symbol refers to the same constituent element.

[0040] Although terms such as "first" and "second" are used to describe various constituent elements, these constituent elements are certainly not limited to these terms. These terms are used merely to distinguish one constituent element from others. Therefore, the "first constituent element" mentioned below can certainly also be a "second constituent element" within the technical concept of this invention. A single expression includes multiple expressions as long as there is no clearly different meaning in the text.

[0041] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same or similar reference numerals are used to assign the same or similar elements to the same components in the drawings.

[0042] Figure 1 This is a perspective view of a display device according to an embodiment. Figure 2 yes Figure 1 An exploded perspective view of the display device. Figure 3 yes Figure 1 A schematic cross-sectional view of the display device.

[0043] Reference Figures 1 to 3 The display device 1 includes a display panel 10, a window substrate 20, and an adhesive layer 30. The display device 1 may be configured such that the display panel 10, the adhesive layer 30, and the window substrate 20 are sequentially stacked in the thickness direction (e.g., the third direction DR3). The display device 1 can be manufactured by assembling the display panel 10 and the window substrate 20 using the adhesive layer 30. Here, "assembly" refers to the process of integrating a first component with a second component through physical bonding such as bonding or adhesion, as well as chemical bonding.

[0044] Display device 1 can display images via display surface IS.

[0045] The display device 1 can be applied to an electronic device in which a display surface IS is applied to one surface, such as a smartphone, a television, a tablet PC, a mobile phone, a video phone, an electronic book reader, a desktop PC, a notebook computer, a netbook, a workstation, a server, a PDA, a PMP (portable multimedia player), an MP3 player, a medical device, a camera, or a wearable device.

[0046] In the drawing, the display surface IS is a surface placed on the upper surface of the display device 1, and a case in which the display surface IS is a planar shape defined by a first direction DR1 and a second direction DR2 different from the first direction DR1 is shown. For example, the first direction DR1 and the second direction DR2 can be directions orthogonal to each other. A display direction can be defined in the normal direction of the display surface IS. A case in which the display direction is a third direction DR3 is shown.

[0047] However, this is an example, and a display device of another embodiment can be implemented to have a shape in which the display surface IS is bent, in which case the display direction can have a plurality of directions.

[0048] The normal direction of the display surface IS, that is, the thickness direction of the display panel 10 refers to the third direction DR3. The upper surface (or front surface) and the lower surface (or rear surface) of each component are distinguished by the third direction DR3. However, the directions referred to by the first direction DR1 to the third direction DR3 are relative concepts, and can be changed to other directions.

[0049] The display surface IS can include a display region DA, which is a region in which an image is displayed, and a non-display region NDA, which is adjacent to the display region DA. The display region DA can be defined by each light emitting element, and the display region DA can include a plurality of color regions (not shown) that are regions in which light of a predetermined color is emitted, respectively.

[0050] The non-display region NDA is a region in which an image is not displayed. The display region DA can be a quadrangular shape. The non-display region NDA can be configured to surround the display region DA in a planar surface. However, embodiments are not limited thereto, and the shape of the display region DA and the shape of the non-display region NDA can be designed relatively.

[0051] As an embodiment, the display panel 10 can be an organic light emitting diode (OLED) display panel. Hereinafter, although the case where the display panel 10 is an organic light emitting display panel is exemplified, as long as the inventive idea is not changed, it can be applied to a quantum dot OLED display panel, a liquid crystal display panel, a micro LED display panel, a plasma display panel, an electrophoretic display panel, a MEMS display panel, an electrowetting display panel, and the like.

[0052] The display panel 10 can include a base substrate 11, a TFT circuit layer 12, a light emitting element layer 13, an encapsulation layer 14, and an input sensing layer 15, which are sequentially stacked in a third direction DR3.

[0053] The base substrate 11 can be a rigid substrate or a flexible substrate. Here, in the case where the base substrate 11 is a rigid substrate, it can be one of a glass substrate, a quartz substrate, a glass-ceramic substrate, and a crystalline glass substrate. In the case where the base substrate 11 is a flexible substrate, it can be one of a thin film substrate including a high molecular organic substance and a plastic substrate. In addition, the base substrate 11 can include a fiber glass reinforced plastic (FRP). The base substrate 11 can be a lower substrate of the display panel 10. As an embodiment, the base substrate 11 can be an opaque substrate.

[0054] The TFT circuit layer 12 can be disposed on the base substrate 11. A plurality of thin film transistors and a wiring connected to the thin film transistors can be disposed in the TFT circuit layer 12. For example, each of the thin film transistors can be in a form in which a semiconductor layer, a gate electrode, and a source / drain electrode are sequentially stacked with an insulating layer interposed therebetween.

[0055] The semiconductor layer can include amorphous silicon, poly silicon, low temperature poly silicon, and an organic semiconductor. The gate electrode and the source / drain electrode can include aluminum (Al), copper (Cu), titanium (Ti), and molybdenum (Mo).

[0056] The light emitting element layer 13 can be disposed on the TFT circuit layer 12. As an example, the light emitting element can be an organic light emitting diode. For example, the organic light emitting diode can be in a form in which an anode, a hole transport layer, an organic light emitting layer, an electron transport layer, and a cathode are sequentially stacked.

[0057] The anode can be electrically connected to the source / drain electrode of a part of the thin film transistors in the TFT circuit layer 12. The anode can be formed of a material having a large work function. For example, the anode can include indium-tin-oxide (ITO), indium-zinc-oxide (IZO), zinc oxide (ZnO), or indium oxide (In2O3), etc. The cathode can be formed of a material having a small work function. For example, the cathode can include Li, Ca, LiF / Ca, LiF / Al, Al, Mg, Ag, Pt, Pd, Ni, Au, Nd, Ir, Cr, BaF2, Ba, or a compound or a mixture thereof (e.g., a mixture of Ag and Mg, etc.).

[0058] An encapsulation layer 14 can be disposed on the light emitting element layer 13. The encapsulation layer 14 can be in a form of an encapsulation substrate or an encapsulation film formed of a plurality of layers. In a case where the encapsulation layer 14 is in the form of the encapsulation film, an inorganic film and / or an organic film can be included. For example, the encapsulation layer 14 can be in a form in which an inorganic film, an organic film, and an inorganic film are sequentially stacked. The encapsulation layer 14 can prevent external air and moisture from penetrating into the light emitting element layer 13 and the TFT circuit layer 12.

[0059] An input sensing layer 15 can be disposed on the encapsulation layer 14. The input sensing layer 15 can include a plurality of sensing electrodes. The sensing electrodes can sense a touch, a hovering, a gesture, a proximity, etc. caused by a user's body. The sensing electrodes can be formed in different shapes according to various types such as a resistive type, a capacitive type, an electro-magnetic type (EM), an optical type, etc.

[0060] In this case, when the sensing electrodes are configured in a capacitive manner, the sensing electrodes can be configured in a self-capacitive type, a mutual-capacitive type, or the like.

[0061] On the other hand, when the sensing electrodes are configured in a self-capacitive type, each sensing electrode can be independently driven, and a sensing signal corresponding to a static capacitance formed by each sensing electrode and a user's body can be provided to a corresponding connection wiring. When the sensing electrodes are configured in a mutual-capacitive type, a sensing signal can be received through a connection wiring corresponding to a partial sensing electrode, and a driving signal can be transmitted through a connection wiring corresponding to another sensing electrode adjacent to the partial sensing electrode and forming a mutual capacitance with the partial sensing electrode. When a user's body is close, the mutual capacitance between the partial sensing electrode and the other sensing electrode can change, and based on a difference in a sensing signal caused thereby, it can be detected whether or not a user's touch.

[0062] In several other embodiments, the input sensing layer 15 can also be omitted.

[0063] The window substrate 20 can be disposed on the display panel 10. The display device 1 can be a front light emission type or a double-sided light emission type that emits light to the window substrate 20 side. The window substrate 20 can be formed of a transparent substrate such as glass or plastic.

[0064] The display panel 10 and the window substrate 20 can be assembled to each other by the adhesive layer 30 located therebetween. That is, the display device 1 can be manufactured by including a process of assembling the display panel 10 and the window substrate 20 by the adhesive layer 30.

[0065] That is, the adhesive layer 30 is located between the display panel 10 and the window substrate 20 to combine the two. For example, the adhesive layer 30 can include a thin film having adhesiveness, an optically clear adhesive (OCA). As another example, the adhesive layer 30 can also include an optically clear resin (OCR).

[0066] The lower surface 20b of the window substrate 20 and the upper surface 30a of the adhesive layer 30 can be brought into contact, and the lower surface 30b of the adhesive layer 30 and the upper surface 10a of the display panel 10 can be brought into contact, thereby combining the display panel 10, the adhesive layer 30, and the window substrate 20 to constitute the display device 1. At this time, the upper surface 20a of the window substrate 20 can include the display surface IS. The lower surface 10b of the display panel 10 can be a lower surface of the base substrate 11, or in other embodiments, can be a lower surface of a housing member or a frame that surrounds the outside of the display device 1.

[0067] On the other hand, in the case where the display panel 10 and the window substrate 20 are assembled using the adhesive layer 30, when there is a surface defect (refer to Figure 9 on the surfaces of them, light emitted toward the window substrate 20 side hits the surface defect and is scattered. Such a surface defect can cause a situation where a user recognizes a picture defect.

[0068] The display device 1 can be assembled after a surface defect is found early on the surfaces of the display panel 10 and the window substrate 20 and repaired before they are assembled using the adhesive layer 30. Hereinafter, a manufacturing method of the display device 1 for this is described.

[0069] Figure 4 is an algorithm sequence diagram showing a part of the process of the manufacturing method of the display device to which an embodiment of the present application relates. Figures 5 to 8 is a perspective view showing a part of the process of the surface defect inspection step of Figure 4 Figures 9 to 10 is a cross-sectional view showing the process of Figure 5 Figure 11 is a graph showing a part of the results measured through the process of Figure 5 Figure 12 is a final computer simulation result image of the display device schematically showing the results obtained through the process of Figures 5 to 8 Figure 13 is a cross-sectional view for explaining the error correction step of Figure 4 Figure 14 is a graph for explaining the error correction step of Figure 4 Figure 15 is a sequence diagram showing the detailed steps of the repair step of Figure 4

[0070] Referring to Figure 4 , the display device 1 can be manufactured by the assembling step S420 including the process of assembling the display panel 10 and the window substrate 20 using the adhesive layer 30, and the manufacturing method of the display device 1 can include the surface defect inspection step S100, the error correction step S200, the defect presence / absence confirmation step S300, and the repair step S410 executed before the assembling step S420. The manufacturing method of the display device 1 executes the repair step S410 when it is determined that there is a defect in the defect presence / absence confirmation step S300 (YES of S300), but can omit the repair step S410 and execute the assembling step S420 when it is determined that there is no defect in the defect presence / absence confirmation step S300 (NO of S300).

[0071] ​​​​​​​In the present specification, the explanation is made in a manner that each step is sequentially executed in a flowchart, but as long as the idea of the present invention is not changed, it is obvious that part of the steps shown as sequentially executed can be executed simultaneously, or the order of the steps can be changed, or part of the steps can be omitted, or other steps can be included between the steps.

[0072] In addition, the present invention is explained below by way of example of manufacturing the display device 1 by the assembling step S420 of assembling the display panel 10 and the window substrate 20 using the adhesive layer 30, but as long as the first unit and the second unit are assembled by the adhesive unit in manufacturing the display device 1, the present invention can be applied. That is, in the present embodiment, the first unit corresponds to the display panel 10, the second unit corresponds to the window substrate 20, and the adhesive unit corresponds to the adhesive layer 30.

[0073] In combination Figures 5 to 8 In the explanation, as an example, the surface defect inspection step S100 can include a process of performing scanning in at least one direction with respect to the object surface. For example, the surface defect inspection step S100 can include a four-direction scanning process. The four-direction scanning process can be performed using the inspection device 1000. The inspection device 1000 can be an independent additional device located outside the display device 1.

[0074] As an example, the inspection device 1000 can include a light emitting portion 100 and a light receiving portion 200. The inspection device 1000 can emit light from the light emitting portion 100 toward the display surface IS over the display surface IS of the display device 1, and collect light reflected from the object surface by the light receiving portion 200.

[0075] Hereinafter, for convenience of explanation, a direction opposite to the first direction DR1 is defined as a fifth direction DR5, and a direction opposite to the second direction DR2 is defined as a fourth direction DR4, and the explanation is made in this manner. That is, the fifth direction DR5, the first direction DR1, the fourth direction DR4, and the second direction DR2 can correspond to the up, down, left, and right directions of the display surface IS reference (on a plane), respectively.

[0076] As an example, the light emitted from the light emitting portion 100 can be light of a specific color. For example, the light can be green light having a wavelength of about 495 nm to 600 nm. In addition, as an example, the light can be laser light. However, the above-described wavelength and kind of the light are only examples, and are not limited thereto.

[0077] When light emitted from the light-emitting unit 100 reaches the target surface within the display device 1, it can have a linear light pattern. That is, light emitted from the light-emitting unit 100 can irradiate a surface of the target unit to form a scan line SL in the form of a linear light. In the figure, only the case where the scan line SL is formed on the upper surface 20a of the display surface IS, i.e., the window substrate 20, is shown. However, scan lines SL can be formed on the upper and lower surfaces of other units depending on the propagation of the light path. In other words, light irradiated onto the display surface IS can pass through the display surface IS and multiple units below it, forming a light path through multiple units.

[0078] As one embodiment, the light-emitting unit 100 may utilize slit light to form a scan line SL as a linear beam. For example, it may be configured such that a slit (not shown) is separately provided in the light-emitting unit 100 of the inspection device 1000, so that light is emitted through the slit, and when the emitted light illuminates the surface of the object as a target, a scan line SL is formed.

[0079] Light illuminating the surface of an object as a target, forming a scan line SL, can be reflected and collected by the light-receiving unit 200. The inspection device 1000 can analyze the light collected by the light-receiving unit 200 and simulate the surface condition at the location where the light is scanned (reflected) in a computer. The inspection device 1000 can be configured to move the scan line SL along the scanning direction, and the surface condition can be simulated by a computer in the scanning direction.

[0080] As one embodiment, the inspection device 1000 can form a scan line SL that extends vertically or horizontally, and scan the surface of the target object in multiple directions while moving the scan line SL in one direction intersecting with the scan line SL and in another direction.

[0081] For example, such as Figure 5 As shown, the inspection device 1000 can form a scan line SL extending in either the second direction DR2 or the fourth direction DR4, and move the scan line SL along the first direction DR1 to perform scanning. At this time, the scanning direction is equivalent to the first direction DR1. This situation can be referred to as the scanning step S111 of the first direction DR1.

[0082] Then, as Figure 6 As shown, the inspection device 1000 can form a scan line SL extending in either the first direction DR1 or the fifth direction DR5, and move the scan line SL along the second direction DR2 to perform scanning. At this time, the scanning direction is equivalent to the second direction DR2. This situation can be referred to as the scanning step S112 of the second direction DR2.

[0083] Then, as Figure 7As shown, the inspection apparatus 1000 can form the scan line SL so as to extend in the first direction DR1 or the fifth direction DR5, and move the scan line SL along the fourth direction DR4 to perform scanning. At this time, the scanning direction corresponds to the fourth direction DR4. This case can be referred to as a scanning step S113 in the fourth direction DR4.

[0084] Then, as shown in FIG. 11B, the inspection apparatus 1000 can form the scan line SL so as to extend in the second direction DR2 or the fourth direction DR4, and move the scan line SL along the fifth direction DR5 to perform scanning. At this time, the scanning direction corresponds to the fifth direction DR5. This case can be referred to as a scanning step S114 in the fifth direction DR5. Figure 8

[0085] As the object surface is moved and scanned in a plurality of directions (for example, four directions), the final computer simulation result described later can become accurate, and the position and the shape of the surface defect can be accurately grasped.

[0086] In the drawings, the case where the scanning steps S111 to S114 are set in the order of the scanning step S111 in which the scanning direction is the first direction DR1, the scanning step S112 in which the scanning direction is the second direction DR2, the scanning step S113 in which the scanning direction is the fourth direction DR4, and the scanning step S114 in which the scanning direction is the fifth direction DR5 is described as an example, but is not limited to the order described. The order of the four-direction scanning steps S111 to S114 described above can be combined in various ways.

[0087] In addition, the embodiment is described as an example in which the object surface is moved and scanned in four directions, but is not limited thereto. If necessary, the object surface can be moved and scanned in one direction once or in the same direction a plurality of times. If necessary, the object surface can also be moved and scanned in other plurality of directions.

[0088] Next, the scanning step S111 in the first direction DR1 will be described in detail. The scanning steps S112 in the second direction DR2, S113 in the fourth direction DR4, and S114 in the fifth direction DR5 can be performed by a person skilled in the art in substantially the same manner as the scanning step S111 in the first direction DR1, and thus the description of the scanning steps S112 to S114 will be replaced by the description of the scanning step S111 in the first direction DR1.

[0089] Referring to FIG. 11A, Figure 9 ​Before the display panel 10 and the window substrate 20 are combined by the adhesive layer 30, the three can be arranged at a predetermined interval therebetween. For example, the display panel 10, the adhesive layer 30, and the window substrate 20 can be arranged in this order at an interval, the interval between the window substrate 20 and the adhesive layer 30 can be set to a first interval dl, and the interval between the display panel 10 and the adhesive layer 30 can be set to a second interval d2. Here, the first interval dl and the second interval d2 can be the same width or different widths. As an example, the first interval dl and the second interval d2 can be set to a width of several micrometers to several millimeters.

[0090] In other words, if the display panel 10, the adhesive layer 30, and the window substrate 20 are arranged in this order at an interval in the third direction DR3, the upper surface 10a of the display panel 10 and the lower surface 30b of the adhesive layer 30 face each other at the second interval d2, and the upper surface 30a of the adhesive layer 30 and the lower surface 20b of the window substrate 20 face each other at the first interval dl.

[0091] As an example, the object surface can include the upper surface 20a of the window substrate 20, the upper surface 30a of the adhesive layer 30, the lower surface 30b of the adhesive layer 30, and the upper surface 10a of the display panel 10, but is not limited thereto.

[0092] As an example, a scan line SL can be formed on each of the upper surface 20a of the window substrate 20, the upper surface 30a of the adhesive layer 30, the lower surface 30b of the adhesive layer 30, and the upper surface 10a of the display panel 10 by a beam of light emitted toward the upper surface 20a of the window substrate 20 over the display device 1. As an example, the beam of light emitted toward the upper surface 20a of the window substrate 20 over the display device 1 can be refracted each time it passes through the window substrate 20, the adhesive layer 30, and the display panel 10. Thus, each scan line SL formed on each of the upper surface 20a of the window substrate 20, the upper surface 30a of the adhesive layer 30, the lower surface 30b of the adhesive layer 30, and the upper surface 10a of the display panel 10 by the beam of light emitted toward the upper surface 20a of the window substrate 20 can not be formed on a virtual straight line. Each scan line SL on the upper surface 20a of the window substrate 20, the upper surface 30a of the adhesive layer 30, the lower surface 30b of the adhesive layer 30, and the upper surface 10a of the display panel 10 can be formed almost simultaneously.

[0093] The light emitted from the light emitting section 100 can pass through the partial sections until it is irradiated to the surface as a target. For example, in order to form the scan line SL on the upper surface 30a of the adhesive layer 30, the light emitted from the light emitting section 100 can pass through the window substrate 20. In addition, in order to form the scan line SL on the lower surface 30b of the adhesive layer 30, the light emitted from the light emitting section 100 can pass through the window substrate 20 and the adhesive layer 30. When the light emitted from the light emitting section 100 is reflected on the upper surface 20a of the window substrate 20, the light can be reflected without passing through each section.

[0094] Each scan line SL formed on the upper surface 20a of the window substrate 20 as each object surface, the upper surface 30a of the adhesive layer 30, the lower surface 30b of the adhesive layer 30, and the upper surface 10a of the display panel 10 is reflected by each object surface, and thus can be collected by the light receiving section 200.

[0095] The inspection device 1000 can move each scan line SL formed on each object surface in the following manner, i.e., in the first direction DR1 as a scan direction. The light reflected on each object surface can be collected by the light receiving section 200.

[0096] Also referring to Figure 10 When each scan line SL is moved in the scan direction, a part of each scan line SL can meet the surface defect 2000 formed on the surface of the partial object surface. For example, the surface defect 2000 can include a case where a foreign matter is formed on the surface and / or a case where a concave-convex is formed on the surface (not shown).

[0097] A part of the light emitted to the object surface can meet the surface defect 2000 formed on the surface and be reflected to an undesired position. In addition, a part of the light emitted to the object surface meets the surface defect 2000 formed on the surface and can be reflected, and thus can exhibit a color difference of a different degree from a reference color difference exhibited in a normal state.

[0098] The light reflected to the undesired position exhibits a color difference of a different degree from the reference color difference, and can be collected by the light receiving section 200 or can not be collected. In addition, in a case where the light reflected to the undesired position is collected by the light receiving section 200, the light amount of the reflected light can be different from a reference light amount (light amount of the reflected light in a case where there is no surface defect 2000).

[0099] Referring to Figure 11 , the inspection device 1000 moves the scan line SL formed by the emitted light in the first direction DR1 while collecting the reflected light, and can express this as a graph. Figure 11Each of the graphs is a graph showing the amount of collected light information with respect to a position varying along the first direction DR1. Here, the amount of collected light information can include, for example, the amount of collected light or specific information on the collected light such as color difference information. However, the kind of the amount of collected light information is not limited to this, and other kinds of information can be collected as the amount of collected light information.

[0100] As shown in Figure 10 , if it is assumed that there is no surface defect 2000 on the upper surface 20a of the window substrate 20 and there is a surface defect 2000 on the upper surface 30a of the adhesive layer 30, the amount of collected light information collected with the upper surface 30a of the adhesive layer 30 as the target surface can be represented by a schematic graph as shown in Figure 11 , and the amount of collected light information collected with the upper surface 20a of the window substrate 20 as the target surface can be represented by a schematic graph as shown in Figure 11 . If the graph is shown with the lower surface 30b of the adhesive layer 30 and the upper surface 10a of the display panel 10, which do not have the surface defect 2000, as the target surfaces, it is as shown in Figure 11 (B) of

[0101] The inspection device 1000 can collect the amount of collected light information lower than the reference value at the specific position where the surface defect 2000 is formed, and thus the display panel 10, the adhesive layer 30, and the window substrate 20 can be computer-simulated.

[0102] The final computer simulation result can be analyzed by integrating the amounts of collected light information collected by performing the four-direction scanning steps on the target surfaces, and the final computer simulation result of the display panel 10, the adhesive layer 30, and the window substrate 20 can be derived by computer simulation as shown in Figure 12 . The computer simulation can use various distributions for optimizing the inspection performance of each unit of the display device 1.

[0103] For example, the final computer simulation result can represent the display device 1_simul including the display panel 10_simul, the adhesive layer 30_simul, and the window substrate 20_simul in an exploded perspective view. The surface defect 2000_simul formed on the upper surface 30a of the adhesive layer 30 can be represented in the final computer simulation result.

[0104] That is, the surface defect inspection step S100 can include a process of determining the position, kind, and form of the surface defect 2000 formed on the surface of the adhesive layer 30 by image analysis using the final computer simulation result.

[0105] On the other hand, the manufacturing method of the display device 1 can perform an error correction step S200 before the computer simulation.

[0106] In several embodiments, as shown in FIG. 10, in order to prepare the surface defect inspection step S100, different intervals can be provided between the facing surfaces during the process of arranging the display panel 10, the adhesive layer 30, and the window substrate 20. For example, a first interval dl can be provided between one side edge of the window substrate 20 and one side edge of the adhesive layer 30, and a third interval dl_l different from the first interval dl can be provided between the other side edge of the window substrate 20 and the other side edge of the adhesive layer 30. A second interval d2 can be provided between one side edge of the display panel 10 and one side edge of the adhesive layer 30, and a fourth interval d2_l different from the second interval d2 can be provided between the other side edge of the display panel 10 and the other side edge of the adhesive layer 30. Figure 13 If the display panel 10, the adhesive layer 30, and the window substrate 20 are arranged in the above-described state, when the inspection device 1000 moves the scan line SL along the first direction DR1 while collecting the light reflected from the object surface by the upper surface 30a of the adhesive layer 30, the graph indicating the amount of collected light information can have different characteristics from the graph of (A) of FIG. 9. As shown in the example of FIG. 10, in the case where the facing lower surface 20b of the window substrate 20 and the upper surface 30a of the adhesive layer 30 are farther apart as they advance in the first direction DR1, as shown in the graph of (A) of FIG. 9, the amount of collected light information can be more different from the reference value as it advances in the first direction DR1.

[0107] Figure 11 Figure 13 Figure 14

[0108] By the error correction step S200, the error can be compensated so that the graph of (A) of FIG. 9 is corrected to the graph of (B) of FIG. 10. Figure 14 Figure 14 The graph of (B) of FIG. 10 can be a graph that is compensated to substantially have the same characteristics as the graph of (A) of FIG. 9. As one embodiment, the error compensation that corrects the graph of (A) of FIG. 9 to the graph of (B) of FIG. 10 can use chromatic aberration of refracted light. For example, the method of compensating the error can use the difference between the reference chromatic aberration set in advance when normally arranged as shown in FIG. 11 and the degree of chromatic aberration collected when not normally arranged as shown in FIG. 12. However, the error correction step S200 can use various known compensation methods in addition to the compensation method using chromatic aberration. Figure 14 Figure 11 Figure 14 Figure 14 Figure 9 Figure 11

[0109] As described above, after the error correction step S200, the position, type, and form of the surface defect 2000 can be determined by the final computer simulation result. ​​​​​​​​​​​

[0110] Referring to Figure 15 , the repairing step S410 can include a polishing step S411 and a cleaning step S412.

[0111] In several embodiments, either one of the polishing step S411 and the cleaning step S412 can be omitted. For example, if the surface defect 2000 is a case where a foreign matter is formed on the surface, only the cleaning step S412 can be performed.

[0112] As an embodiment, if the surface defect 2000 is a case where a concavo-convex is formed on the surface, the polishing step S411 and the cleaning step S412 can be performed in this order. Here, the polishing step S411 can include at least one of a chemical process and a mechanical process.

[0113] The display device 1 is manufactured by the above-described method, so that the cost and time for repairing the surface defects of each unit can be minimized before the manufacture of the display device 1 is completed.

[0114] Next, a manufacturing method of a display device according to other embodiments will be described. Hereinafter, the same components as those in the drawings of Figures 1 to 15 will be omitted from description, and the same or similar symbols will be used.

[0115] Figure 16 is an algorithm sequence diagram showing a part of a manufacturing method of a display device according to other embodiments of the present application.

[0116] Referring to Figure 16 , the manufacturing method of a display device according to the present embodiment is different from the embodiments according to Figure 3 in that the surface defect inspection step (e.g., S100_1 or S100_2) to the repairing step S410 are repeated at least once.

[0117] As described above, the surface defect (not shown) can include various forms of defects in addition to a case where a foreign matter is formed on the surface and / or a case where a concavo-convex is formed on the surface. As an embodiment, the manufacturing method of a display device can take a plurality of defect types as targets, and perform the surface defect inspection step (e.g., S100_1 or S100_2) to the repairing step S410 for each target defect. Hereinafter, a case where one surface defect where a foreign matter is formed on the surface and two surface defects where a concavo-convex is formed on the surface are taken as targets, and the surface defect inspection step (e.g., S100_1 or S100_2) to the repairing step S410 are performed for each target defect will be described. However, in a case where the number of defect types targeted according to the embodiments is more than two, the surface defect inspection step (e.g., S100_1 or S100_2) to the repairing step S410 can be repeated more than twice.

[0118] As one embodiment, the manufacturing method of the display device can include a surface defect countermeasuring step S10 and a two-surface defect countermeasuring step S20 performed before the assembling step S420 of assembling the display panel 10 and the window substrate 20 using the adhesive layer 30.

[0119] The surface defect countermeasuring step S10 can include a surface defect inspection step S100_1, an error correction step S200, a defect presence / absence confirming step S300, and a repair step S410. If it is determined that a defect exists in the defect presence / absence confirming step S300 of the surface defect countermeasuring step S10 (YES of S300), the repair step S410 is performed, and the two-surface defect countermeasuring step S20 is performed, but if it is determined that a defect does not exist in the defect presence / absence confirming step S300 (NO of S300), the repair step S410 can be omitted and the two-surface defect countermeasuring step S20 is performed.

[0120] Likewise, the two-surface defect countermeasuring step S20 can include a two-surface defect inspection step S100_2, an error correction step S200, a defect presence / absence confirming step S300, and a repair step S410. If it is determined that a defect exists in the defect presence / absence confirming step S300 of the two-surface defect countermeasuring step S20 (YES of S300), the repair step S410 is performed and the assembling step S420 is performed, but if it is determined that a defect does not exist in the defect presence / absence confirming step S300 (NO of S300), the repair step S410 can be omitted and the assembling step S420 is performed.

[0121] Figure 17 FIG. 6 is a cross-sectional view showing a part of a process of a surface defect inspection step in a manufacturing method of a display device according to yet another embodiment.

[0122] Referring to Figure 17 , the manufacturing method of the display device according to the embodiment is different from Figure 9 the embodiment in that light is also irradiated to the lower surface 20b of the window substrate 20 to inspect a surface defect 2001 formed in the lower surface 20b of the window substrate 20. Hereinafter, the description will be made based on the scanning step S111_1 in the first direction DR1.

[0123] As one embodiment, the inspection device 1000 can emit light from the light emitting part 100 to the upper surface 20a of the window substrate 20, the lower surface 20b of the window substrate 20, the upper surface 30a of the adhesive layer 30, the lower surface 30b of the adhesive layer 30, and the upper surface 10a of the display panel 10 as object surfaces, thereby forming respective scanning lines SL and collecting light reflected by the surfaces.

[0124] Thus, the surface defect 2001 formed on the lower surface 20b of the window substrate 20 and the surface defect 2000 formed on the upper surface 30a of the adhesive layer 30 can be detected.

[0125] The subsequent processes are performed substantially identically to the processes of Figures 10 to 15 , and thus repeated explanations are omitted.

[0126] Figure 18 is a schematic cross-sectional view of a display device according to still another embodiment. Figure 19 is a cross-sectional view of a portion of a manufacturing method of a display device according to Figure 18 , in which a surface defect inspection step is more specifically shown.

[0127] Referring to Figure 18 , the display device 2 according to the present embodiment differs from the display device 1 according to Figure 3 in that it has a plurality of adhesive layers (31, 32).

[0128] As one embodiment, the display device 2 can include the display panel 10, the polarizing layer 40, and the window substrate 20, which are sequentially stacked. In addition, the display device 2 can further include a plurality of adhesive layers (31, 32) disposed between the display panel 10, the polarizing layer 40, and the window substrate 20 to assemble the respective constituent elements. For example, the first adhesive layer 31 can be disposed between the display panel 10 and the polarizing layer 40, and the second adhesive layer 32 can be disposed between the polarizing layer 40 and the window substrate 20.

[0129] The first adhesive layer 31 and the second adhesive layer 32 can be selected, respectively, from among the substances of the adhesive layer 30 exemplified in Figure 3 .

[0130] For example, the polarizing layer 40 can have a polarizing axis (not shown) in one direction. The polarizing layer 40 can be a coated polarizing layer 40 or a polarizing layer 40 formed by evaporation. The polarizing layer 40 can be formed by coating a substance including a dichroic dye and a liquid crystal compound.

[0131] Referring to Figure 19 , compared to the embodiment of Figure 9 , light can be irradiated to the respective upper surfaces 31a, 32a and lower surfaces 31b, 32b of the first adhesive layer 31 and the second adhesive layer 32 before the display panel 10, the polarizing layer 40, and the window substrate 20 are assembled using the first adhesive layer 31 and the second adhesive layer 32, thereby inspecting surface defects 2000 formed on the upper surface 31a of the first adhesive layer 31, the upper surface 32a of the second adhesive layer 32, the lower surface 31b of the first adhesive layer 31, and the lower surface 32b of the second adhesive layer 32.

[0132] As one embodiment, the inspection device 1000 can emit slit light from the light emitting section 100 toward each of the object surfaces of the upper surface 20a of the window substrate 20, the upper surface 31a of the first adhesive layer 31, the lower surface 31b of the first adhesive layer 31, the upper surface of the polarizing layer 40, the upper surface 32a of the second adhesive layer 32, the lower surface 32b of the second adhesive layer 32, and the upper surface 10a of the display panel 10 to form a scan line SL.

[0133] The subsequent processes are performed substantially identically to those of Figures 10 to 15 , and thus repeated explanations are omitted.

[0134] Figure 20 is an algorithm sequence diagram showing a part of the processes of the manufacturing method of the display device according to another embodiment of the present application.

[0135] Referring to Figure 20 , the manufacturing method of the display device according to the present embodiment is distinguished from that of Figure 4 in that the surface defect inspection step S100_3 is performed by dividing it into a step of confirming a defect position and a step of irradiating light onto the surface of each unit and collecting the reflected light.

[0136] As one embodiment, the surface defect inspection step S100_3 can include a step S131 of confirming a defect position and a step S132 of irradiating light onto the surface of each unit and collecting the reflected light, which are sequentially performed. Here, each unit can correspond to the first adhesive layer, the second adhesive layer, the display panel, the polarizing layer, and the window substrate.

[0137] The step S131 of confirming a defect position, which is sequentially performed in the surface defect inspection step S100_3, can correspond to a step of confirming a defect position on a plane. For example, by the above-described scanning processes in four directions, the defect position on the plane can be grasped.

[0138] The step S132 of grasping the defect position on the plane and irradiating light onto the surface of each unit and collecting the reflected light can be performed. The step S132 of irradiating light onto the surface of each unit and collecting the reflected light can correspond to a step of performing surface scanning of each unit with the above-described defect position as the center.

[0139] According to the present embodiment, the defect position on the plane can be first grasped, light can be irradiated onto the surface of each unit with the corresponding part where the defect position on the plane is found as the center, and the reflected light can be collected, and a precise computer simulation can be performed using the collected light, so that the form of the surface defect or the like can be effectively grasped.

[0140] The embodiments of the present application are explained above with reference to the accompanying drawings, but it is understood by those skilled in the art that the present application can be implemented in other specific forms without changing the technical idea or essential characteristics of the present application. Therefore, the above-described embodiments are in all aspects illustrative, and should not be construed as limiting.

Claims

1. A manufacturing method of a display device, which is a method of manufacturing a display device by assembling a first unit and a second unit using an adhesive unit, the method comprising: a surface inspection step of emitting a beam of light to an upper surface of the second unit, irradiating a first light to an upper surface of the adhesive unit, irradiating a second light to a lower surface of the adhesive unit, and collecting a process of the first light and the second light reflected by the upper surface and the lower surface of the adhesive unit respectively, wherein the beam of light forms the first light at the upper surface of the adhesive unit, and the beam of light forms the second light at the lower surface of the adhesive unit; a step of confirming surface defects of the respective surfaces; and a repairing step of removing the surface defects, the first light passes through the second unit and is refracted, and then is reflected from the upper surface of the adhesive unit, the second light passes through the second unit and the adhesive unit in this order and is refracted, and then is reflected from the lower surface of the adhesive unit.

2. The manufacturing method of a display device according to claim 1, wherein the first unit is a display panel, and the second unit is a window substrate, the adhesive unit includes an optically transparent adhesive.

3. The manufacturing method of a display device according to claim 1, wherein in the surface inspection step, the beam of light has a wavelength of 495 nm to 600 nm.

4. The manufacturing method of a display device according to claim 3, wherein in the surface inspection step, the beam of light is slit light that passes through a slit so as to form a scan line in one direction on the respective surfaces.

5. The manufacturing method of a display device according to claim 4, wherein in the surface inspection step, a direction in which the scan line moves is a direction that intersects with a direction in which the scan line extends.

6. The manufacturing method of a display device according to claim 1, wherein in the surface inspection step, the beam of light is irradiated to the respective surfaces of the adhesive unit at the same time.

7. The manufacturing method of a display device according to claim 6, wherein the beam of light irradiated to at least one of the respective surfaces of the adhesive unit, a first surface facing the upper surface, and a second surface facing the lower surface is not formed on a virtual straight line.

8. The manufacturing method of a display device according to claim 1, wherein in the surface inspection step, the beam of light is irradiated to the respective surfaces of the adhesive unit in a state in which the first unit, the second unit, and the adhesive unit are separated by a predetermined interval.

9. The manufacturing method of a display device according to claim 1, wherein the repairing step includes at least one of a process of cleaning, a mechanical mask, and a chemical polishing of the surface in which the surface defect is confirmed.

10. The manufacturing method of a display device according to claim 1, wherein the surface inspection step includes a step of confirming a defect position, and a step of irradiating the beam of light to the respective surfaces of the adhesive unit and collecting light reflected by the respective surfaces. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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