CN112397406A

CN112397406A - Method for manufacturing display device

Info

Publication number: CN112397406A
Application number: CN202010601194.6A
Authority: CN
Inventors: 黄太进
Original assignee: Samsung Display Co Ltd
Current assignee: Samsung Display Co Ltd
Priority date: 2019-08-19
Filing date: 2020-06-29
Publication date: 2021-02-23
Also published as: KR20210022224A

Abstract

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

Description

Method for manufacturing display device

Technical Field

The present invention relates to a method for manufacturing a display device, and more particularly, to a method for repairing a surface defect by detecting an expression defect before manufacturing the display device.

Background

Recently, with the development of multimedia, the importance of display devices is increasing. In response to this, flat panel display devices such as liquid crystal display devices, plasma display devices, organic light emitting display devices, and the like are being commercialized.

The display device is manufactured through a process of assembling a plurality of cells using an adhesive unit. Generally, a display device is tested when it is shipped from a factory. In individual cases, the luminance unevenness of the screen of the display device can be found by the test.

The brightness unevenness of the picture may be caused by surface defects occurring at the surface of the adhesion unit. However, when the step of testing finds a surface defect occurring on the surface of the bonded unit, a high cost and time are required until the surface defect is repaired.

Disclosure of Invention

The present invention has been made to solve the problem of providing a method for manufacturing a display device in which surface defects are inspected and repaired before a plurality of units are assembled by an adhesive unit.

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

A method for manufacturing a display device according to an embodiment of the present invention for solving the above-described problems includes a step of assembling a first unit and a second unit by an adhesive unit, and the method includes, before the step of assembling: a surface inspection step including a process of irradiating light to each of upper and lower surfaces of the bonding unit and collecting light reflected by the each surface; confirming surface defects of the respective surfaces; and a repair step of removing the surface defect.

The first unit may be a display panel, the second unit may be a window substrate, and the Adhesive unit may include an Optically Clear Adhesive (optical Clear Adhesive).

In the surface inspection step, the light may have a wavelength of 495nm to 600 nm.

In the surface inspection step, the light may be slit light that has passed through a slit to form a scanning line in a direction on the surfaces.

In the surface inspection step, a direction in which the scan line moves may be a direction intersecting a direction in which the scan line extends.

In the surface inspection step, the light may be simultaneously irradiated to the respective surfaces of the bonding unit.

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

In the surface inspection step, the light may be irradiated to the respective surfaces of the bonding unit in a state where the first unit, the second unit, and the bonding unit are spaced apart by a predetermined interval.

The repairing step may include at least one of cleaning, mechanical masking, and chemical polishing the surface where the surface defect is identified.

The surface inspection step may include: confirming a defect position; and a step of irradiating the light to the respective surfaces of the bonding unit and collecting the light reflected by the respective surfaces.

Additional embodiments are also specifically included in the detailed description and the drawings.

(effect of the invention)

According to embodiments of the present invention, it is possible to inspect and repair surface defects before assembling a plurality of units of a display device using an adhesive unit.

This can save the cost and time required for manufacturing the display device.

The effects according to the embodiments are not limited to those exemplified above, and further effects are included in the present specification.

Drawings

Fig. 1 is a perspective view of a display device according to an embodiment.

Fig. 2 is an exploded perspective view of the display device of fig. 1.

Fig. 3 is a schematic cross-sectional view of the display device of fig. 1.

Fig. 4 is a sequence diagram of an algorithm showing a part of a process of a method for manufacturing a display device according to an embodiment of the present invention.

Fig. 5 to 8 are perspective views showing a partial process of the surface defect inspection step of fig. 4.

Fig. 9 and 10 are cross-sectional views showing the process of fig. 5 in more detail.

Fig. 11 is a graph showing a part of the results measured by the process of fig. 5.

Fig. 12 schematically shows a final computer simulation result image of the display device obtained through the processes of fig. 5 to 8.

Fig. 13 is a cross-sectional view for explaining the error correction process of fig. 4.

Fig. 14 is a table for explaining the error correction procedure of fig. 4.

Fig. 15 is a sequence diagram showing the detailed procedure of the repair procedure of fig. 4.

Fig. 16 is an algorithm sequence chart showing a partial process of a method for manufacturing a display device according to another embodiment of the present invention.

Fig. 17 is a sectional view showing a part of the process of the surface defect inspection step in more detail in the manufacturing method of the display device according to the other embodiment.

Fig. 18 is a schematic sectional view of a display device according to still another embodiment.

Fig. 19 is a sectional view showing a partial process of a surface defect inspection step in more detail in the method of manufacturing the display device of fig. 18.

Fig. 20 is an algorithm sequence chart showing a partial process of a method for manufacturing a display device according to still another embodiment of the present invention.

Detailed Description

The advantages and features of the present invention and methods of accomplishing the same will become apparent by reference to the following detailed description of the embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be embodied in various forms different from each other, and the embodiments are provided only for completeness of disclosure of the present invention and to inform the scope of the invention to those skilled in the art, and the present invention is defined only by the scope of claims.

The case where elements or layers are "on" other elements or layers includes not only the case where the elements or layers are directly on the other elements but also the case where the other layers or other elements are sandwiched therebetween. Throughout the specification, the same reference numerals denote the same constituent elements.

Although the terms first, second, etc. are used to describe various components, it is needless to say that these components are not limited to these terms. These terms are used only for distinguishing one constituent element from other constituent elements. Therefore, the first component mentioned below may be a second component within the technical idea of the present invention. A single expression includes a plurality of expressions unless the expression clearly indicates otherwise in the text.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same or similar reference numerals are given to the same constituent elements on the drawings.

Fig. 1 is a perspective view of a display device according to an embodiment. Fig. 2 is an exploded perspective view of the display device of fig. 1. Fig. 3 is a schematic cross-sectional view of the display device of fig. 1.

Referring to fig. 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 in a form in which the display panel 10, the adhesive layer 30, and the window substrate 20 are sequentially stacked in the thickness direction (for example, the third direction DR 3). The display device 1 may be manufactured by assembling the display panel 10 and the window substrate 20 using the adhesive layer 30. Here, "assembly" refers to a step of integrating the first component and the second component by physical bonding such as adhesion or adhesion, or chemical bonding.

The display device 1 can display an image through the display surface IS.

The present invention can be applied to an electronic device having a display surface IS applied to one surface, such as a smart phone, 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.

In the drawing, the display surface IS a surface placed on the upper surface of the display device 1, and IS shown in a case of a planar shape defined by the first direction DR1 and the second direction DR2 different from the first direction DR 1. For example, the first direction DR1 and the second direction DR2 may be mutually orthogonal directions. The display direction may be defined in the normal direction of the display surface IS. The case where the display direction is the third direction DR3 is shown.

However, this IS an illustration, and the display device of the other embodiment may be implemented to have a shape in which the display surface IS bent, in which case the display direction may have a plurality of directions.

The normal direction of the display surface IS, that IS, the thickness direction of the display panel 10 IS the third direction DR 3. The upper surface (or front surface) and the lower surface (or rear surface) of each member are distinguished by the third direction DR 3. However, the directions indicated by the first direction DR1 to the third direction DR3 are relative concepts, and may be changed to other directions.

The display surface IS may include: a display area DA which is an area where an image is displayed; and a non-display area NDA adjacent to the display area DA. The display area DA may be defined by each light emitting element, and may include a plurality of color areas (not shown) as areas that emit light of a predetermined color, respectively.

The non-display area NDA is an area where no image is displayed. The display area DA may be a quadrangular shape. The non-display area NDA may be configured to surround the display area DA on a plane. However, the embodiment is not limited thereto, and the shape of the display area DA and the shape of the non-display area NDA may be relatively designed.

As an example, the display panel 10 may be an Organic Light Emitting Diode (OLED) display panel. Although the following description will be made by taking the case where the display panel 10 is an organic light emitting display panel as an example, the present invention can be applied to a quantum dot Organic Light Emitting (OLED) display panel, a liquid crystal display panel (liquid crystal display panel), a micro LED display panel (micro LED display panel), a plasma display panel (plasma display panel), an electrophoretic display panel (electrophoretic display panel), a MEMS display panel (micro electro mechanical system display panel), an electrowetting display panel (electro wetting display panel), and the like, as long as the inventive concept is not changed.

The display panel 10 may 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 the third direction DR 3.

The base substrate 11 may be a rigid (rigid) substrate or a flexible (flex) substrate. Here, when the base substrate 11 is a rigid (rigid) substrate, it may be one of a glass substrate, a quartz substrate, a glass ceramic substrate, and a crystallized glass substrate. In the case where the base substrate 11 is a flexible substrate, it may be one of a thin film substrate including a high molecular organic substance and a plastic substrate. In addition, the base substrate 11 may also include a Fiber glass reinforced plastic (FRP). The base substrate 11 may be a lower substrate of the display panel 10. As an example, the base substrate 11 may be an opaque substrate.

A TFT circuit layer 12 may be disposed on the base substrate 11. A plurality of thin film transistors and wirings connected to the thin film transistors may be disposed in the TFT circuit layer 12. For example, each of the thin film transistors may be formed by sequentially stacking a semiconductor layer, a gate electrode, and source/drain electrodes with an insulating layer interposed therebetween.

The semiconductor layer may include amorphous silicon (amorphous silicon), polycrystalline silicon (poly silicon), low temperature poly silicon (low temperature poly silicon), and organic semiconductors. The gate electrode and the source/drain electrodes may include aluminum (Al), copper (Cu), titanium (Ti), molybdenum (Mo).

A light-emitting element layer 13 may be disposed on the TFT circuit layer 12. As an example, the light emitting element may be an organic light emitting diode. For example, the organic light emitting diode may be in the form of an anode, a hole transport layer, an organic light emitting layer, an electron transport layer, and a cathode that are sequentially stacked.

The anode may be electrically connected to the source/drain electrodes of a part of the thin film transistors within the TFT circuit layer 12. The anode may be formed including a substance having a large work function. For example, the anode may include Indium-Tin-Oxide (ITO), Indium-Zinc-Oxide (IZO), Zinc Oxide (ZnO), or Indium Oxide (In)₂O₃) And the like. The cathode may be formed including a substance having a small work function. For example, the cathode can include Li, Ca, LiF/Al, Mg, Ag, Pt, Al,Pd、Ni、Au、Nd、Ir、Cr、BaF₂Ba, or a compound or mixture thereof (e.g., a mixture of Ag and Mg, etc.).

The encapsulating layer 14 may be disposed on the light emitting element layer 13. The encapsulation layer 14 may be in the form of an encapsulation substrate or an encapsulation film formed from a multilayer film. In the case where the encapsulation layer 14 is in the form of the encapsulation film, an inorganic film and/or an organic film may be included. For example, the encapsulation layer 14 may be formed by sequentially stacking an inorganic film, an organic film, and an inorganic film. The encapsulating layer 14 can prevent external air and moisture from penetrating into the light emitting element layer 13 and the TFT circuit layer 12.

An input sensing layer 15 may be configured on the encapsulation layer 14. The input sensing layer 15 may include a plurality of sensing electrodes. The sensing electrode may sense a touch (touch), hovering (hovering), gesture (gesture), approach or not, etc. caused by the user's body. The sensing electrode may be formed in various shapes according to various types such as a resistive type (resistive type), a capacitive type (capacitive type), an electromagnetic-inductive type (EM), and an optical type (optical type).

Here, when the sensing electrode is formed by a capacitive method, the sensing electrode may be formed by a self-capacitive method (self-capacitive type), a mutual-capacitive method (mutual-capacitive type), or the like.

On the other hand, in the case where the sensing electrodes are configured by the self-capacitance method, it is possible to independently drive each sensing electrode and supply a sensing signal corresponding to the electrostatic capacitance formed by each sensing electrode and the body of the user to the corresponding connection wiring. In the case where the sensing electrodes are configured by a mutual capacitance method, the sensing signal may be received through the connection wiring corresponding to a part of the sensing electrodes, and the driving signal may be transmitted through the connection wiring corresponding to another adjacent sensing electrode forming a mutual capacitance with the part of the sensing electrodes. Under the condition that the body of the user is close to the sensing electrode, the mutual capacitance between the partial sensing electrode and the other sensing electrodes may be changed, and whether the user touches or not can be detected according to the difference of sensing signals caused by the change of the mutual capacitance.

In several other embodiments, the input sensing layer 15 may also be omitted.

The window substrate 20 may be disposed on the display panel 10. The display device 1 may be of a front emission type or a double-emission type in which light is emitted toward the window substrate 20. The window substrate 20 may be formed of a transparent substrate of glass, plastic, or the like.

The display panel 10 and the window substrate 20 may be assembled with each other with the adhesive layer 30 therebetween. That is, the display device 1 may be manufactured by including a step of assembling the display panel 10 and the window substrate 20 through the adhesive layer 30.

That is, the adhesive layer 30 is positioned between the display panel 10 and the window substrate 20 to bond the two. For example, the Adhesive layer 30 may include a film having Adhesive property, Optically Clear Adhesive (OCA). As another example, the adhesive layer 30 may include an Optically transparent Resin (OCR).

The display device 1 may be configured by bonding the display panel 10, the adhesive layer 30, and the window substrate 20 by bringing the lower surface 20b of the window substrate 20 into contact with the upper surface 30a of the adhesive layer 30 and bringing the lower surface 30b of the adhesive layer 30 into contact with the upper surface 10a of the display panel 10. At this time, the upper surface 20a of the window substrate 20 may include the display surface IS. The lower surface 10b of the display panel 10 may be a lower surface of the base substrate 11, or may be a lower surface of a case member or frame surrounding the exterior of the display apparatus 1 in other embodiments.

On the other hand, when the display panel 10 and the window substrate 20 are assembled by the adhesive layer 30, if there is a surface defect (see 2000 in fig. 9) on the surfaces of these, the light emitted toward the window substrate 20 hits the surface defect and is scattered. Such surface defects may cause a poor picture to be recognized by a user.

The display device 1 may be assembled after surface defects are found on their surfaces and repaired at an early stage before the display panel 10 and the window substrate 20 are assembled using the adhesive layer 30. A method for manufacturing the display device 1 will be described below.

Fig. 4 is a sequence diagram of an algorithm showing a part of a process of a method for manufacturing a display device according to an embodiment of the present invention. Fig. 5 to 8 are perspective views showing a partial process of the surface defect inspection step of fig. 4. Fig. 9 to 10 are sectional views showing the process of fig. 5 in more detail. Fig. 11 is a graph showing a part of the results measured by the process of fig. 5. Fig. 12 schematically shows a final computer simulation result image of the display device obtained through the processes of fig. 5 to 8. Fig. 13 is a cross-sectional view for explaining the error correction process of fig. 4. Fig. 14 is a table for explaining the error correction procedure of fig. 4. Fig. 15 is a sequence diagram showing the detailed procedure of the repair procedure of fig. 4.

Referring to fig. 4, the display device 1 may be manufactured through an assembling step S420 including a 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 may include a surface defect inspection step S100, an error correction step S200, a defect presence/absence confirmation step S300, and a repair step S410, which are performed before the assembling step S420. Although the repairing step S410 is executed when the defect presence/absence confirmation step S300 determines that the defect is present (yes in S300), the manufacturing method of the display device 1 may omit the repairing step S410 and execute the assembling step S420 when the defect presence/absence confirmation step S300 determines that the defect is not present (no in S300).

In this specification, the steps are described as being sequentially executed in a sequence diagram, but it is obvious that some steps shown as being continuously executed may be simultaneously executed, the order of the steps may be changed, some steps may be omitted, or other steps may be further included between the steps, as long as the idea of the invention is not changed.

In addition, although the present invention is described below by taking as an example the case of manufacturing the display device 1 through the step S420 of assembling the display panel 10 and the window substrate 20 by the adhesive layer 30, the present invention may be applied to the case where the first unit and the second unit are assembled by the adhesive means when manufacturing the display device 1. 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.

As described with reference to fig. 5 to 8, the surface defect inspection step S100 may include a process of performing scanning in at least one direction with respect to the surface of the object, as an embodiment. For example, the surface defect inspection step S100 may include a scanning process in four directions. The four-directional scanning process may be performed by the inspection apparatus 1000. The inspection apparatus 1000 may be a separate additional apparatus located outside the display apparatus 1.

As an example, the inspection apparatus 1000 may include a light emitting portion 100 and a light receiving portion 200. The inspection apparatus 1000 may emit light from the light emitting portion 100 toward the display surface IS of the display apparatus 1 above the display surface IS, and collect light reflected from the surface of the object by the light receiving portion 200.

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, to explain. That IS, the fifth direction DR5, the first direction DR1, the fourth direction DR4, and the second direction DR2 may correspond to up, down, left, and right directions of the display surface IS reference (on the plane), respectively.

As an example, the light emitted from the light emitting portion 100 may be light of a specific color. For example, the light may be green light having a wavelength of about 495nm to 600 nm. In addition, as an example, the light may be laser light. However, the wavelength and the type of the light are merely examples, and are not limited thereto.

The light emitted from the light emitting unit 100 may have a linear light form when reaching a target object surface in the display device 1. That is, the light emitted from the light emitting unit 100 may be irradiated on one surface of the target cell to form the scanning line SL in a linear light form. In the drawing, only the case where the scan lines SL are formed on the display surface IS, that IS, the upper surface 20a of the window substrate 20 IS illustrated, but the scan lines SL may be formed on the upper and lower surfaces of other cells according to the travel of the optical path. That IS, light irradiated to the display surface IS may pass through the display surface IS and a plurality of cells below the display surface IS, and an optical path passing through the plurality of cells IS formed.

As an example, the light emitting section 100 may use slit light in order to form the scanning lines SL as line light. For example, it may be provided that: the light emitting unit 100 of the inspection apparatus 1000 is provided with a slit (not shown) so that light is emitted through the slit, and the scanning line SL is formed when the emitted light is irradiated to the target surface.

Light irradiated toward the target surface to form the scanning line SL may be reflected to be collected by the light receiving portion 200. The inspection apparatus 1000 may analyze the light collected by the light receiving part 200 and simulate the surface state of the position where the light is scanned (reflected) in a computer. The inspection apparatus 1000 may be arranged to move the scanning line SL in the scanning direction and simulate the surface state by a computer in the scanning direction.

As an example, the inspection apparatus 1000 may form the scanning line SL to extend vertically or horizontally, and scan the target surface in a plurality of directions while moving the scanning line SL in one direction and the other direction intersecting the scanning line SL.

For example, as shown in fig. 5, the inspection apparatus 1000 may perform scanning by forming the scanning line SL to extend in the second direction DR2 or the fourth direction DR4 and moving the scanning line SL along the first direction DR 1. At this time, the scanning direction corresponds to the first direction DR 1. This case may be referred to as a scanning step S111 of the first direction DR 1.

Then, as shown in fig. 6, the inspection apparatus 1000 may perform scanning by forming the scanning line SL to extend in the first direction DR1 or the fifth direction DR5 and moving the scanning line SL along the second direction DR 2. At this time, the scanning direction corresponds to the second direction DR 2. This case may be referred to as a scanning step S112 of the second direction DR 2.

Then, as shown in fig. 7, the inspection apparatus 1000 may form the scanning line SL to extend in the first direction DR1 or the fifth direction DR5, and perform scanning by moving the scanning line SL in the fourth direction DR 4. At this time, the scanning direction corresponds to the fourth direction DR 4. This case may be referred to as a scanning step S113 of the fourth direction DR 4.

Then, as shown in fig. 8, the inspection apparatus 1000 may perform scanning by forming the scanning line SL to extend in the second direction DR2 or the fourth direction DR4 and moving the scanning line SL along the fifth direction DR 5. At this time, the scanning direction corresponds to the fifth direction DR 5. This case may be referred to as a scanning step S114 of the fifth direction DR 5.

As the target surface is scanned while moving in a plurality of directions (for example, four directions), a final computer simulation result described later can be accurate, and the position and form of the surface defect can be accurately grasped.

In the figure, the description has been given by taking as an example the case where 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 set, but the order is not limited to the above. The order of the above-described four-direction scanning steps S111 to S114 may be combined in various ways.

In addition, the embodiment has been described taking as an example the case where the object surface is scanned while moving in four directions, but is not limited thereto. It is also possible to move in one direction and scan the object surface once or scan the object surface multiple times in the same direction, as required. The movement and scanning of the object surface can also be performed in other directions, as desired.

Next, the scanning step S111 of the first direction DR1 will be described in detail. A person skilled in the art can perform the scanning step S112 of the second direction DR2, the scanning step S113 of the fourth direction DR4, and the scanning step S114 of the fifth direction DR5 in substantially the same manner as the scanning step S111 of the first direction DR1, and thus replace the descriptions of the scanning step S112 of the second direction DR2, the scanning step S113 of the fourth direction DR4, and the scanning step S114 of the fifth direction DR5 with the descriptions of the scanning step S111 of the first direction DR 1.

Referring to fig. 9, before the display panel 10 and the window substrate 20 are coupled to each other by the adhesive layer 30, the three may be arranged with a predetermined interval therebetween. For example, the display panel 10, the adhesive layer 30, and the window substrate 20 may be arranged in this order with a distance therebetween, and the distance between the window substrate 20 and the adhesive layer 30 may be set to the first distance d1, and the distance between the display panel 10 and the adhesive layer 30 may be set to the second distance d 2. Here, the first interval d1 and the second interval d2 may have the same width or different widths. As an example, the widths of the first and second intervals d1 and d2 may be set between several micrometer units and several millimeter units.

In other words, when the display panel 10, the adhesive layer 30, and the window substrate 20 are arranged in this order at intervals 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 with the second interval d2 therebetween, and the upper surface 30a of the adhesive layer 30 and the lower surface 20b of the window substrate 20 face each other with the first interval d1 therebetween.

As an example, the object surfaces may 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 are not limited thereto.

As an example, the scanning lines SL may be formed 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 by one beam of light emitted toward the upper surface 20a of the window substrate 20 on the display device 1. As an example, a beam of light emitted toward the upper surface 20a of the window substrate 20 on the display device 1 may be refracted each time it passes through the window substrate 20, the adhesive layer 30, and the display panel 10. Accordingly, the scanning lines SL formed 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 by the single light emitted toward the upper surface 20a of the window substrate 20 may not be formed on a virtual straight line. The respective scan lines SL located 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 may be formed almost simultaneously.

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

The scanning lines SL formed 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, which are the surfaces of the objects, are reflected by the surfaces of the objects, and can be collected by the light receiving unit 200.

The inspection apparatus 1000 may move each scanning line SL formed on the surface of each object along a first direction DR1 which is a scanning direction. The light reflected on the surface of each object can be collected by the light receiving unit 200.

Referring to fig. 10, when each scan line SL moves in the scanning direction, a portion of each scan line SL meets the surface defect 2000 formed on a portion of the object surface. For example, the surface defect 2000 may include a case where a foreign substance is formed on the surface and/or a case where a concave-convex is formed on the surface (not shown).

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

The light reflected to an undesired position may or may not be collected by the light receiving unit 200 because it exhibits a color difference different from the reference color difference. In addition, when the light reflected to an undesired position is collected by the light receiving portion 200, there is a possibility that the amount of the reflected light may be different from the reference amount of light (the amount of the reflected light in the case where there is no surface defect 2000).

Referring to fig. 11, the inspection apparatus 1000 collects reflected light while moving the scanning line SL formed by the emitted light in the first direction DR1, and may represent this as a graph. Each graph of fig. 11 is a graph showing the amount of collected light information with respect to the position that changes along the first direction DR 1. Here, the collected light information amount may include specific information on the collected light, such as the collected light amount or the collected color difference information, for example. However, the type of the collected light information amount is not limited to this, and other types of information may be collected as the collected light information amount.

As shown in fig. 10, assuming 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 may be schematically shown in fig. 11 (a), and the amount of collected light information collected with the upper surface 20a of the window substrate 20 as the target surface may be schematically shown in fig. 11 (B). Fig. 11 (B) shows a graph in which the lower surface 30B of the adhesive layer 30 and the upper surface 10a of the display panel 10, in which the surface defect 2000 is not present, are shown as target surfaces.

The inspection apparatus 1000 may collect the amount of collected light information lower than the reference value at a specific position where the surface defect 2000 is formed, and thus may simulate the display panel 10, the adhesive layer 30, and the window substrate 20 by a computer.

The final computer simulation result can be obtained by comprehensively analyzing the collected light information amount collected by completing the scanning steps in all the four directions on the object surface, and deriving the final computer simulation result by performing computer simulation on the display panel 10, the adhesive layer 30, and the window substrate 20 as shown in fig. 12. The computer simulation described may utilize various profiles for optimizing the inspection performance of the units of the display device 1.

For example, the final computer simulation result may represent the display apparatus 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 results of the computer simulation at the end may show surface defects 2000_ simull formed on the upper surface 30a of the adhesive layer 30.

That is, the surface defect inspection step S100 may include a process of determining the position, type, 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.

On the other hand, the method of manufacturing the display device 1 may execute the error correction step S200 before the computer simulation.

In several embodiments, as shown in fig. 13, in order to prepare the surface defect inspection step S100, the facing surfaces may have different intervals during the arrangement of the display panel 10, the adhesive layer 30, and the window substrate 20. For example, it is possible to provide a first interval d1 between one side edge of the window substrate 20 and one side edge of the adhesive layer 30 and a third interval d1_1 different from the first interval d1 between the other side edge of the window substrate 20 and the other side edge of the adhesive layer 30. The second interval d2 may be provided between one side edge of the display panel 10 and one side edge of the adhesive layer 30, and the fourth interval d2_1 different from the second interval d2 may be provided between the other side edge of the display panel 10 and the other side edge of the adhesive layer 30.

When the display panel 10, the adhesive layer 30, and the window substrate 20 are arranged in the above-described state, the graph showing the amount of collected light information may have a characteristic different from that of the graph of fig. 11 (a) when the inspection apparatus 1000 collects light reflected from the surface of the object by the upper surface 30a of the adhesive layer 30 while moving the scanning line SL in the first direction DR 1. As shown in the example of fig. 13, in the case where the lower surface 20b of the window substrate 20 and the upper surface 30a of the adhesive layer 30 facing each other are farther away as the light advances in the first direction DR1, the collected light information amount may be substantially different from the reference value as the light information amount advances in the first direction DR1 as shown in the graph of fig. 14 (a).

In the error correction step S200, the error can be compensated so that the graph of fig. 14 (a) is corrected to the graph of fig. 14 (B). The graph of fig. 14 (B) may be a graph compensated to have substantially the same characteristics as the graph of fig. 11 (a). As an example, the error compensation for correcting the graph of fig. 14 (a) to the graph of fig. 14 (B) may use the chromatic aberration of the refracted light. For example, the method of compensating for errors may be performed by using the difference between the degree of a reference color difference set in advance in the normal alignment as shown in fig. 9 and the degree of a color difference collected in the abnormal alignment as shown in fig. 11. However, in the error correction step S200, various known compensation methods may be used in addition to the compensation method using the chromatic aberration.

As described above, the position, type, and form of the surface defect 2000 can be specified from the final computer simulation result through the error correction step S200.

Referring to fig. 15, the repairing step S410 may include a polishing step S411 and a cleaning step S412.

In some embodiments, any of the polishing step S411 and the cleaning step S412 may be omitted. For example, if the surface defect 2000 is a case where foreign matter is formed on the surface, only the cleaning step S412 may be performed.

As an example, if the surface defect 2000 is a case where a concave-convex surface is formed on the surface, the polishing step S411 and the cleaning step S412 may be sequentially performed. Here, the polishing step S411 may include at least one of a chemical process and a mechanical process.

The display device 1 is manufactured by the above-described method, so that the cost and time for repairing the surface defect of each cell can be minimized before the manufacturing of the display device 1 is completed.

Next, a method for manufacturing a display device according to another embodiment will be described. Hereinafter, the same components as those in the drawings of fig. 1 to 15 will not be described, and the same or similar reference numerals will be used.

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

As described above, the surface defect (not shown) may include various types of defects in addition to the case where a foreign substance is formed on the surface and/or the case where an unevenness is formed on the surface. As an example, the manufacturing method of the display device may perform the surface defect inspection step (e.g., S100_1 or S100_2) to the repair step S410 for each target defect, respectively, with a plurality of defect types as targets. Hereinafter, a case will be described as an example in which the surface defect inspection step (e.g., S100_1 or S100_2) to the repair step S410 are performed for one type of surface defect in which foreign matter is formed on the surface and two types of surface defects in which unevenness is formed on the surface. However, when the number of types of defects targeted according to the embodiment exceeds two, the surface defect inspection step (e.g., S100_1 or S100_2) to the repair step S410 may be repeatedly performed more than twice.

As an embodiment, the manufacturing method of the display device may include one kind of surface defect corresponding step S10 and two kinds of surface defects corresponding step S20, which are performed before the assembling step S420 of assembling the display panel 10 and the window substrate 20 using the adhesive layer 30.

A surface defect mapping step S10 may include a surface defect inspection step S100_1, an error correction step S200, a defect existence/non-existence verification step S300, and a repair step S410. If it is determined that the defect exists in the one-kind surface defect corresponding step S10 in the defect existence/nonexistence determination step S300 (yes in S300), the repair step S410 is performed and the two-kind surface defect corresponding step S20 is performed, but if it is determined that the defect does not exist in the defect existence/nonexistence determination step S300 (no in S300), the repair step S410 may be omitted and the two-kind surface defect corresponding step S20 may be performed.

Similarly, the two types of surface defect matching step S20 may include two types of surface defect inspection step S100_2, an error correction step S200, a defect existence/non-existence confirmation step S300, and a repair step S410. If it is determined that the defect exists in the defect existence confirmation step S300 of the two types of surface defect correspondence step S20 (yes in S300), the repair step S410 is performed and the assembly step S420 is performed, but if it is determined that the defect does not exist in the defect existence confirmation step S300 (no in S300), the repair step S410 may be omitted and the assembly step S420 may be performed.

Fig. 17 is a sectional view showing a part of a process of a surface defect inspection step in more detail in a manufacturing method of a display device according to still another embodiment.

Referring to fig. 17, the manufacturing method of the display device according to the present embodiment is different from the embodiment according to fig. 9 in that light is further irradiated to the lower surface 20b of the window substrate 20 to inspect a surface defect 2001 formed on the lower surface 20b of the window substrate 20. Hereinafter, the scanning step S111_1 in the first direction DR1 will be described as a reference.

As an example, the inspection apparatus 1000 may form each scanning line SL and collect light reflected by the surfaces by emitting light from the light emitting portion 100 with 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 target surfaces.

Thereby, 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.

The subsequent processes are substantially the same as those of fig. 10 to 15, and therefore, redundant description is omitted.

Fig. 18 is a schematic sectional view of a display device according to still another embodiment. Fig. 19 is a sectional view showing a partial process of a surface defect inspection step in more detail in the method of manufacturing the display device of fig. 18.

Referring to fig. 18, the display device 2 according to the present embodiment is different from the display device 1 of fig. 3 in that it includes a plurality of adhesive layers (31, 32).

As an example, the display device 2 may include a display panel 10, a polarizing layer 40, and a window substrate 20, which are sequentially stacked. The display device 2 may further include a plurality of adhesive layers (31, 32) disposed between the respective components of the display panel 10, the polarizing layer 40, and the window substrate 20 to assemble the respective components. For example, the first adhesive layer 31 may be disposed between the display panel 10 and the polarizing layer 40, and the second adhesive layer 32 may be disposed between the polarizing layer 40 and the window substrate 20.

The first adhesive layer 31 and the second adhesive layer 32 may be selected from the adhesive layers 30 listed in fig. 3.

For example, the polarizing layer 40 may have a polarizing axis of one direction (not shown). The polarizing layer 40 may be a coating-type polarizing layer 40 or a polarizing layer 40 formed by evaporation. The polarizing layer 40 may be formed by coating a substance including a dichroic dye and a liquid crystal compound.

Referring to fig. 19, in comparison with the embodiment of fig. 9, before the display panel 10, the polarizing layer 40, and the window substrate 20 are assembled by the first adhesive layer 31 and the second adhesive layer 32, the upper surfaces 31a and 32a and the lower surfaces 31b and 32b of the first adhesive layer 31 and the second adhesive layer 32 are irradiated with light, and the 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 can be inspected.

As an example, the inspection apparatus 1000 may form the scanning lines SL by emitting slit light from the light emitting section 100 to the target surfaces, with 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 as the target surfaces.

Referring to fig. 20, the method of manufacturing the display device according to the present embodiment is different from the embodiment of fig. 4 in that the surface defect inspection step S100_3 is performed by being divided into a step of confirming a defect position and a step of irradiating light to the surface of each cell and collecting the reflected light.

As an embodiment, the surface defect inspection step S100_3 may include a step S131 of confirming a defect position and a step S132 of irradiating light to the surface of each cell and collecting the reflected light, which are sequentially performed. Here, each cell may correspond to the first adhesive layer, the second adhesive layer, the display panel, the polarizing layer, and the window substrate.

The step of confirming the defective position S131 sequentially performed in the surface defect inspection step S100_3 may correspond to a step of confirming the defective position on a plane. For example, by the above-described scanning process in four directions, the defect position on the plane can be grasped.

Step S132 of grasping the defect position on the plane, irradiating light to the surface of each cell, and collecting the reflected light may be performed. The step S132 of irradiating light to the surface of each cell and collecting the reflected light may correspond to a step of performing surface scanning of each cell centering on the above-described defective position.

According to the present embodiment, it is possible to grasp the defect position on the plane first, irradiate light to the surface of each cell centering on the corresponding portion where the defect position on the plane is found, and collect the reflected light, perform accurate computer simulation using the collected light, whereby the form of the surface defect and the like can be grasped efficiently.

While the embodiments of the present invention have been described with reference to the drawings, it will be understood by those skilled in the art that the embodiments may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The embodiments described above are therefore to be considered in all respects as illustrative and not restrictive.

Claims

1. A method of manufacturing a display device through a step of assembling a first unit and a second unit by an adhesive unit, the method comprising, before the step of assembling:

a surface inspection step including a process of irradiating light to each of upper and lower surfaces of the bonding unit and collecting light reflected by the each surface;

confirming surface defects of the respective surfaces; and

and a repairing step of removing the surface defects.

2. The method for manufacturing a display device according to claim 1,

the first unit is a display panel, the second unit is a window substrate,

the bonding unit includes an Optically Clear Adhesive (Optically Clear Adhesive).

3. The method for manufacturing a display device according to claim 1,

in the surface inspection step, the light has a wavelength of 495nm to 600 nm.

4. The method for manufacturing a display device according to claim 3,

in the surface inspection step, the light is slit light that has passed through a slit to form a scanning line in a direction on the surfaces.

5. The method for manufacturing a display device according to claim 4,

in the surface inspection step, a direction in which the scanning line moves is a direction intersecting a direction in which the scanning line extends.

6. The method for manufacturing a display device according to claim 1,

in the surface inspection step, the respective surfaces of the bonding unit are simultaneously irradiated with the light.

7. The method for manufacturing a display device according to claim 6,

the light irradiated to at least one of the surfaces of the bonding unit, the first surface facing the upper surface, and the second surface facing the lower surface is not formed on a virtual straight line.

8. The method for manufacturing a display device according to claim 1,

in the surface inspection step, the light is irradiated to the respective surfaces of the bonding unit in a state where the first unit, the second unit, and the bonding unit are spaced apart by a predetermined interval.

9. The method for manufacturing a display device according to claim 1,

the repairing step includes at least one of cleaning, mechanical masking, and chemical polishing the surface identified with the surface defect.

10. The method for manufacturing a display device according to claim 1,

the surface inspection step includes: confirming a defect position; and a step of irradiating the light to the respective surfaces of the bonding unit and collecting the light reflected by the respective surfaces.