JP2010008188A - Apparatus of inspecting display panel, inspection method, and method of manufacturing display panel using it - Google Patents

Abstract

In inspection of a display panel, foreign matter adhering to the surface of the display panel and a dark spot are distinguished and detected.
A surface of a liquid crystal display panel is imaged by using a camera from two different viewing angles. The viewing angle is switched using the light shielding plates 3a and 3b of the optical system 18 including the reflecting mirrors 1a to 2b. From the obtained pixel image, a defective part whose luminance is lowered is detected, and whether or not the pixel images captured at different viewing angles match the color arrangement of the peripheral pixels of the defective part is compared. In the case of a foreign substance with a defective part attached to the surface, the color arrangement of pixels reflected in the background changes depending on the viewing angle, so that the dark spot and the foreign substance can be distinguished.

Description

  The present invention relates to an inspection apparatus and an inspection method used for optical inspection of a display panel such as a flat panel display, and a display panel manufacturing method using the same.

  Display panels such as liquid crystal display panels (Liquid Color Display: LCD) are widely used in electronic devices such as televisions, personal computers, and mobile phones.

  FIG. 1 shows an example of a liquid crystal display panel. The liquid crystal display panel 100 includes two transparent substrates 101 and 104, and a liquid crystal layer 102 and a color filter layer 103 are disposed between the transparent substrates 101 and 104. Transparent electrodes are provided on the surfaces of the transparent substrate 101 and the color filter layer 103 on the liquid crystal layer 102 side, respectively. In the color filter layer 103, a colored layer 103R that transmits red light, a colored layer 103G that transmits green light, and a colored layer 103B that transmits blue light are arranged in a certain order. A transparent optical film 105 or the like is attached to the surface of the transparent substrate 104 (the upper surface in FIG. 1). Further, the liquid crystal display panel 100 is provided with a backlight (not shown) on the back surface side (lower side in FIG. 1) of the transparent substrate 101, and controls the amount of light transmitted from the backlight for each pixel. Display.

  By the way, in the liquid crystal display panel 100, there may be a dark spot 98 where the display of a specific pixel remains dark due to some trouble that occurs at the time of manufacture. Further, a black spot may be generated on the display surface of the liquid crystal display panel 100 due to the foreign matter 99 attached to the surface of the transparent substrate 104 or the optical film 105. Such display defects due to dark spots or foreign matters may occur in organic EL display panels, plasma display panels, and the like.

  For this reason, in the manufacturing process of the display panel, it is necessary to inspect whether or not there are dark spots or foreign matters attached by visual inspection or an inspection device, and whether or not the number of dark spots or foreign matters is less than a specified value. is there.

A conventional inspection apparatus detects a defect by a method of optically detecting the luminance of a pixel in a state where a predetermined test pattern is displayed on a display panel.
Japanese Patent Laid-Open No. 11-132720 Japanese Patent Laid-Open No. 10-111237 JP-A-11-64237 JP 05-172759 A

  However, in recent years, pixels have become finer with higher definition of display panels, and it has become difficult to detect dark spots by visual inspection. Further, the conventional inspection apparatus cannot distinguish between the foreign matter adhering to the display panel surface and the dark spot of the display panel with an optical film or the like attached to the display panel.

  Therefore, in the inspection of the display panel, it is an object to distinguish and detect the foreign matter adhering to the surface of the display panel and the dark spot.

  The above-described object is to provide an optical system that reflects the surface of the display panel from two or more different viewing angles, an imaging unit that acquires an image formed by the optical system as a pixel image, and a luminance from the pixel image that is higher than a specified value. A control unit that detects a lower defective part and compares the defective part of the pixel image projected from different directions to determine whether the defective part is a foreign matter attached to the display panel or a dark spot of the display panel. This can be achieved by an inspection apparatus equipped with

  In the above-described inspection apparatus, the defect sites are compared using pixel images obtained by imaging the surface of the display panel from different directions. For this reason, the knowledge of the depth direction of a defective part is acquired, and the foreign material adhering to a display panel and the dark spot of a display panel can be distinguished.

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

(First embodiment)
FIG. 2 is a block diagram showing the inspection apparatus according to the first embodiment. FIG. 3 is a schematic diagram illustrating the optical system of the inspection apparatus according to the first embodiment (part 1). FIG. 4 is a schematic diagram illustrating the optical system of the inspection apparatus according to the first embodiment (part 2). 5A and 5B are partially enlarged views of an image formed on the camera by the optical system.

  As shown in FIG. 2, the inspection apparatus 10 according to the present embodiment includes a sample stage 15, an optical system 18, and a camera 11. A camera drive unit 12 is connected to the camera 11, an optical system drive unit 13 is connected to the optical system 18, and a sample stage drive unit 14 is connected to the sample stage 15. The camera driving unit 12, the optical system driving unit 13, and the sample stage driving unit 14 are connected to the control unit 16, and these driving units 12, 13, and 14 are connected to the camera 11 and the optical system by a control signal from the control unit 16. 18 and the sample stage 15 are driven. The display unit 17 is connected to the control unit 16 and displays information such as inspection results. Hereinafter, each part will be further described.

  The sample stage 15 moves the liquid crystal display panel 100 in the horizontal direction and the vertical direction based on the drive signal from the sample stage drive unit 14.

As shown in FIG. 3, the optical system 18 includes a first reflecting mirror 1a, a second reflecting mirror 1b, a third reflecting mirror 2a, a fourth reflecting mirror 2b, an imaging lens 5, a first light shielding plate 3a, and a second light shielding. A plate 3b and a light shielding plate 4 are provided. The first reflecting mirror 1a and the second reflecting mirror 1b are arranged so that the reflecting surfaces are perpendicular to the surface of the liquid crystal display panel 100 and the reflecting surfaces face each other. The first reflecting mirror 1 a reflects the surface of the liquid crystal display panel 100 from a first viewing angle inclined by α ₁ ° with respect to the surface of the liquid crystal display panel 100. As shown in FIG. 4, the second reflecting mirror 1 b reflects the surface of the liquid crystal display panel 100 from a second viewing angle inclined by α ₂ ° with respect to the surface of the liquid crystal display panel 100. The first and second reflecting mirrors 1a, 1b is movable in direction of arrow X _2, it is possible to change the viewing angle alpha ₁ and alpha _2.

A first light-shielding plate 3a and a second light-shielding plate 3b are disposed above the first and second reflecting mirrors 1a and 1b. The first and second shielding plates 3a, 3b is movable in the direction indicated by arrow X ₁ in FIG. The first and second light shielding plates 3a and 3b selectively allow only the light reflected by one of the first reflecting mirror 1a and the second reflecting mirror 1b to pass through. For example, when the first and second light shielding plates 3a and 3b are at the positions shown in FIG. 3, the light reflected by the first reflecting mirror 1a is allowed to pass, and when the first and second light shielding plates 3a and 3b are at the positions shown in FIG. The light reflected by the reflecting mirror 1b is allowed to pass through.

  An imaging lens 5 is disposed above the first and second light shielding plates 3a and 3b. The imaging lens 5 has a function of causing the camera 11 to image the light reflected by the first reflecting mirror 1a or the second reflecting mirror 1b. As the imaging lens 5, it is preferable to use a lens having a focal depth deeper than the thickness of the transparent substrate 104. Thereby, a clear image from the surface of the transparent substrate 104 to the surface of the color filter 103 can be formed on the camera 11.

  The light shielding plate 4 blocks light other than the light reflected by the first and second reflecting mirrors 1 a and 1 b and suppresses the noise component from entering the camera 11. The light shielding plate 4 is not limited to the shape and arrangement shown in FIGS. 3 and 4, and may be a plurality of plates, for example.

Above the imaging lens 5, a third reflecting mirror 2a and a fourth reflecting mirror 2b are arranged. The third and fourth reflecting mirrors 2a and 2b are arranged so that the reflecting surfaces are perpendicular to the surface of the liquid crystal display panel 100 and the reflecting surfaces face each other. The third reflecting mirror 2a guides the light reflected by the second reflecting mirror 1b to the camera 11, and the fourth reflecting mirror 2b guides the light reflected by the first reflecting mirror 1a to the camera 11. The third and fourth reflecting mirrors 2a, 2b is movable in the direction of arrow X _2, the first and second reflecting mirror 1a, by changing the position in accordance with the movement 1b, the directing the light to the camera 11 Can do.

  The camera 11 includes a light receiving unit (not shown) such as a CCD element or a CMOS image sensor. In the light receiving portion, an image of the surface of the liquid crystal display panel 100 projected from the first viewing angle or the second viewing angle is formed by the optical system 18, and the first image captured from different viewing angles is obtained by capturing this image. One pixel image and a second pixel image can be acquired.

  In the optical system 18 as described above, it is preferable to adjust the first and second viewing angles so that the first and second viewing angles are symmetric with respect to an axis perpendicular to the liquid crystal display panel 100. Thereby, the brightness | luminance of the background pixel in a 1st pixel image and a 2nd pixel image can be made equivalent, and a defect site | part can be detected easily.

  Next, the inspection of the liquid crystal display panel 100 using the inspection apparatus 10 according to the present embodiment will be described.

First, the liquid crystal display panel 100 is placed on the sample stage 15. Next, the sample stage 15 is moved so that a predetermined area of the liquid crystal display panel 100 can be photographed by the camera 11. Subsequently, by adjusting the positions of the first to fourth reflecting mirrors 1a, 1b, 2a, and 2b of the optical system driving unit 13, the angle α ₁ ° of the first viewing angle and the angle α ₂ ° of the _second viewing angle are set. Set. Further, the position of the imaging lens 5 is adjusted so that the focal position is aligned with the surface of the liquid crystal display panel 100.

  Next, a predetermined test pattern is displayed on the liquid crystal display panel 100 and the backlight is turned on.

  Thereafter, the first and second light shielding plates 3a and 3b are moved to the positions shown in FIG. 3 so that the light reflected by the first reflecting mirror 1a passes therethrough. At this time, if there is a foreign substance 99 on the surface of the transparent substrate 104, an image as shown in FIG. 5A is formed on the light receiving element of the camera 11, for example. Subsequently, an image obtained by projecting the liquid crystal display panel 100 from the first viewing angle is captured by the camera 11 as a first pixel image.

  Next, the first and second light shielding plates 3a and 3b are moved to the positions shown in FIG. 4 to allow the light reflected by the second reflecting mirror 1b to pass therethrough. At this time, for example, an image as shown in FIG. 5B is formed on the light receiving element of the camera 11. Subsequently, an image of the liquid crystal display panel 100 projected from the second viewing angle by the camera 11 is captured as a second pixel image. The first and second pixel images thus captured are sent to the control unit 16 via the camera driving unit 12 and stored in a storage unit inside the control unit 16.

  Next, the control unit 16 detects a defective portion where the luminance is equal to or less than a specified value in the first and second pixel images. For example, the defective part is detected by comparing the pixel image (reference image) of the liquid crystal display panel that is registered in the storage unit of the control unit 16 and does not have a defective part with the first and second pixel images. It can be carried out.

  Subsequently, the control unit 16 determines whether the defective part is a foreign object or a dark spot. This determination can be made, for example, by comparing the color arrangement of the peripheral pixels around the defective part in the first pixel image with the color arrangement of the peripheral pixels around the defective part in the second pixel image. Since the first pixel image and the second pixel image are obtained by reflecting the surface of the liquid crystal display panel 100 from different viewing angles, for example, in the case of a foreign substance adhered to the transparent substrate 104, for example, FIG. As shown in a) and (b), the positions of the pixel images reflected in the background are different. Accordingly, the control unit 16 determines that the defective part is a foreign matter attached to the surface when the color arrangement of the peripheral pixels of the defective part is different between the first and second pixel images. On the other hand, in the case of a dark spot, even if the viewing angle is changed, the color arrangement of the peripheral pixels around the defective part does not change. For this reason, the control part 16 determines with the dark spot of a display panel, when the color arrangement of the surrounding pixel of a defect site | part is the same in the 1st and 2nd pixel image.

  After that, when the field of view of the optical system 18 and the camera 11 is smaller than the screen of the liquid crystal display panel 100, another part of the liquid crystal display panel 100 is driven by driving the sample stage 15 to inspect other parts of the screen. The same inspection is performed for.

  As described above, the inspection apparatus 10 according to the present embodiment can distinguish and detect foreign matter and dark spots on the liquid crystal display panel 100. Usually, the allowable amount of foreign matter adhering to one display panel is different from the allowable amount of dark spots per display panel, so the quality of the display panel is judged according to different criteria for each foreign matter and dark spot. To do.

By the way, in the inspection apparatus 10, depending on the combination of the thickness of the transparent substrate 104 of the liquid crystal display panel 100 and the pixel pitch of the color filter layer 103, the liquid crystal is obtained from the first viewing angle of the angle α ₁ and the _second viewing angle of the angle α ₂ . Even if the display panel is imaged, a foreign object and a dark spot may not be identified. For example, as illustrated in FIG. 6, when pixel images are captured at an angle α ₁ and an angle α ₂ , the color arrangement of the color filter layer 103 reflected in the background of the foreign material 99 may be the same, and the control is performed. The part 16 cannot identify the foreign matter 99 as a dark spot.

In such a case, as shown in FIG. 7, first, second reflecting mirror 1a, 1b and the third, fourth reflecting mirror 2a, that the position of 2b is moved in the direction of arrow X ₂ changing the viewing angle Thus, it is possible to distinguish the foreign object from the dark spot. At this time, the angle α ₃ and the angle α ₄ are determined by calculation so that the color arrangement of the color filter layer 103 reflected in the background of the foreign matter differs based on the pixel pitch of the liquid crystal display panel 100 and the thickness of the transparent substrate 104. be able to.

(Second Embodiment)
Hereinafter, the inspection apparatus according to the second embodiment will be described with reference to FIGS. 8 and 9. FIG. 8 is a schematic diagram showing the optical system of the inspection apparatus according to the second embodiment (No. 1). FIG. 9 is a schematic diagram showing the optical system of the inspection apparatus according to the second embodiment (No. 2).

The inspection apparatus according to the present embodiment employs an optical system 21 instead of the optical system 18 of the first embodiment. As shown in FIGS. 8 and 9, the optical system 21 includes a reflecting mirror 1, a light shielding plate 3, an imaging lens 5, a light shielding plate 4 and a reflecting mirror 2 in order from the sample (liquid crystal display panel 100) side. When the reflecting surface is perpendicular to the surface of the liquid crystal display panel 100 and has the positional relationship shown in FIG. 8, the reflecting mirror 1 projects the surface of the liquid crystal display panel 100 from the first viewing angle of an angle α ₁ °. The reflected light. The light shielding plate 3 and the light shielding plate 4 allow light reflected by the reflecting mirror 1 to pass therethrough and block other light. The imaging lens 5 has a function of causing the camera 11 to image the light reflected by the reflecting plate 1. The reflecting mirror 2 has a reflecting surface perpendicular to the surface of the liquid crystal display panel 100, and guides light that has passed through the imaging lens 5 to the camera 11.

The optical system 21 is formed symmetrically around the central axis Q. By rotating around the central axis Q, an image in which the surface of the liquid crystal display panel 100 is viewed from various viewing angles can be formed on the camera 11. . For example, by rotating 180 ° from the state shown in FIG. 8, as shown in FIG. 9, the surface of the liquid crystal display panel 100 can be projected from the second viewing angle of angle α ₂ °. In the optical system 21, the viewing angle may be changed by allowing the reflecting mirror 1 and the reflecting mirror 2 to move in a horizontal direction with respect to the surface of the liquid crystal display panel 100.

  Other parts of the inspection apparatus according to the present embodiment are the same as those of the inspection apparatus 10 according to the first embodiment (see FIG. 2).

  Below, the test | inspection of the liquid crystal display panel 100 using the test | inspection apparatus which concerns on this embodiment is demonstrated.

First, as in the first embodiment, the liquid crystal display panel 100 is prepared and the optical system is adjusted. Subsequently, as shown in FIG. 8, an image obtained by observing the surface of the liquid crystal display panel 100 from the direction of α ₁ ° is formed on the camera 11, and a first pixel image is captured. Next, the optical system 21 is rotated 180 ° around the central axis Q, and as shown in FIG. 9, an image obtained by observing the surface from the direction of α ₂ ° from the surface of the liquid crystal display panel 100 is formed on the camera 11. A second pixel image is captured.

  Thereafter, in the same manner as in the first embodiment, the control unit 16 detects a defective part from the first and second pixel images, and determines the difference in the color arrangement of the peripheral pixels of the detected defective part from the first and second pixels. Compare with pixel images. Then, the control unit 16 determines that the first and second pixel images have foreign matter attached to the surface when the color arrangement of the peripheral pixels of the defective portion is different, and determines that the same is a dark spot of the display panel.

  As described above, according to the inspection apparatus according to this embodiment, the configuration of the optical system can be further simplified.

(Third embodiment)
Hereinafter, the third embodiment will be described with reference to FIGS. 10 and 11. FIG. 10 is a block diagram showing an inspection apparatus according to the third embodiment. FIG. 11 is a schematic diagram illustrating an optical system of the inspection apparatus according to the third embodiment.

  As shown in FIG. 10, the inspection apparatus 30 of this embodiment includes cameras 11 a and 11 b and an optical system 31. Note that the camera drive circuit 12, the optical system drive circuit 13, the sample stage drive circuit 14, the sample stage 15, the control unit 16, and the display unit 17 of the inspection apparatus 30 are denoted by the same reference numerals as those of the inspection apparatus 10 according to the first embodiment. It is the same as each part made.

  The camera 11a and the camera 11b have a light receiving unit (not shown) such as a CCD element or a CMOS image sensor, for example, and take an image of the surface of the liquid crystal display panel formed on the light receiving unit as a pixel image.

As shown in FIG. 11, the optical system 31 includes imaging lenses 5a and 5b. The imaging lens 5 a has a function of connecting an image of the surface of the liquid crystal display panel 100 projected from the first viewing angle of an angle α ₁ ° to the surface of the liquid crystal display panel 100 to the camera 11 a. The imaging lens 5b has a function of connecting an image of the surface of the liquid crystal display panel 100 projected from the second viewing angle of an angle α ₂ ° to the surface of the liquid crystal display panel 100 to the camera 11b.

  In the optical system 31, the imaging lenses 5a and 5b and the cameras 11a and 11b can be moved in the horizontal direction so that the viewing angle at which the liquid crystal display panel 100 is projected can be adjusted.

As shown in FIG. 11, the inspection by the inspection apparatus 30 of the present embodiment is performed by imaging the surface of the liquid crystal display panel 100 using the camera 11a and the camera 11b. Thereby, the camera 11a can capture a first pixel image obtained by projecting the surface of the liquid crystal display panel 100 from the first viewing angle of the angle α ₁ °. Further, the camera 11b can capture a second pixel image obtained by projecting the surface of the liquid crystal display panel 100 from the second viewing angle of the angle α ₂ °.

  Thereafter, in the same manner as in the first embodiment, the control unit 16 detects a defective part from the first and second pixel images, and determines the difference in the color arrangement of the peripheral pixels of the detected defective part from the first and second pixels. Compare with pixel images. Then, the control unit 16 determines that the first and second pixel images have foreign matter attached to the surface when the color arrangement of the peripheral pixels of the defective portion is different, and determines that the same is a dark spot of the display panel.

  As described above, according to the inspection apparatus according to this embodiment, the configuration of the optical system can be further simplified.

(Other embodiments)
The inspection device according to each of the above embodiments can be used in a manufacturing process of a liquid crystal display panel or a manufacturing process of an electronic device equipped with the liquid crystal display panel.

  In this case, for example, after the transparent substrate 101 and the transparent substrate 104 of the liquid crystal display panel 100 are bonded together and the optical film 105 is bonded onto the transparent substrate 104, the inspection apparatus according to each of the above embodiments is used. The liquid crystal display panel 100 can be inspected. In addition, the liquid crystal display panel 100 can be inspected using the inspection apparatus according to each of the above embodiments at a stage after the liquid crystal display panel 100 is incorporated into an electronic device such as a mobile phone.

  As described above, according to the inspection apparatus according to each of the above embodiments, it is possible to distinguish and detect whether the defective part is a dark spot of the liquid crystal display panel or a foreign substance attached to the surface of the liquid crystal display panel. Thereby, it is possible to sort defective products using different inspection standards for foreign matters and dark spots. Further, by repairing the sorted defective products, it is possible to improve the manufacturing yield.

  Further, in each of the above embodiments, the example of inspecting the liquid crystal display panel 100 has been described. However, the present invention is not limited to this, and the inspection device of each of the above embodiments is not limited to an organic EL panel, a plasma display panel, or the like. It can also be used for inspection or manufacture of display panels.

  Hereinafter, various aspects of the present invention will be collectively described as supplementary notes.

  (Supplementary Note 1) An optical system that reflects the surface of the display panel from two or more different viewing angles, an imaging unit that acquires an image formed by the optical system as a pixel image, and the luminance from the pixel image is lower than a specified value A control unit for detecting a low defective part and comparing the defective part of the pixel image projected from different directions to determine whether the defective part is a foreign matter attached to the display panel or a dark spot of the display panel; And a display panel inspection apparatus.

  (Additional remark 2) The said control part compares the color arrangement | sequence of the surrounding pixel of the said defective part in the said some pixel image, and when the color arrangement of the peripheral pixel of the said defective part differs, the said defective part is said to the said display panel. 2. The display panel inspection according to claim 1, wherein the defect is determined as a foreign matter attached to the display panel, and the defective portion is determined as a dark spot of the display panel when the color arrangement of peripheral pixels of the defective portion is the same. apparatus.

(Supplementary Note 3) The optical system includes two reflecting mirrors arranged such that the reflecting surface is perpendicular to the surface of the display panel and the reflecting surfaces face each other;
A shielding plate that selectively allows only light reflected by one of the two reflecting mirrors to pass through;
An imaging lens that forms an image of the light that has passed through the shielding plate on the imaging unit;
The display panel inspection apparatus according to claim 1, further comprising a reflecting mirror that guides light that has passed through the imaging lens onto the imaging unit.

  (Additional remark 4) The said optical system is symmetrically formed around the central axis of the said optical system, The inspection apparatus of the display panel of Additional remark 3 characterized by the above-mentioned.

  (Supplementary note 5) The display panel inspection apparatus according to supplementary note 4, wherein a viewing angle at which the display panel is projected is changed by rotating the optical system around the central axis.

(Supplementary note 6) The optical system includes two imaging lenses arranged at intervals in a direction parallel to the surface of the display panel,
2. The display panel inspection apparatus according to claim 1, wherein each of the imaging units is disposed at a position where the imaging lens connects the images of the pixels of the display panel.

(Appendix 7) A step of imaging the surface of the display panel from two or more different directions to obtain a plurality of pixel images;
Detecting a defect site having a luminance lower than a specified value from the pixel image;
And comparing the defect sites in the plurality of pixel images to determine whether the defect site is a foreign matter adhering to the display panel or a dark spot of the display panel. .

(Appendix 8) The step of determining whether the defective part is a foreign object or a dark spot is performed by comparing the color arrangement of peripheral pixels of the defective part with two or more pixel images,
When the color arrangement of the surrounding pixels of the defective part is different, the defective part is determined as a foreign matter attached to the display panel,
8. The display panel inspection method according to appendix 7, wherein the defective portion is determined as a dark spot of the display panel when the color arrangement of surrounding pixels of the defective portion is the same.

(Supplementary Note 9) The viewing angles at which the surface of the display panel is imaged are the first viewing angle α ₃ and the second viewing angle α ₄ , and the first viewing angle α ₃ and the second viewing angle α ₄ are the display elements. The supplementary note 7 or 8, characterized in that it is determined based on the pixel pitch of the display element and the thickness of the transparent substrate so that the color arrangement of the pixel image reflected in the background of the foreign matter adhering to the surface of the display element is different. Display panel inspection method.

(Additional remark 10) The process of forming the display panel in which the optical film was stuck,
Capturing a plurality of pixel images by imaging the surface of the display panel from two or more different directions with respect to the surface of the display panel;
Detecting a defect site having a luminance lower than a specified value from the pixel image;
Comparing the color arrangement of the peripheral pixels of the defective part in a plurality of the pixel images to determine whether the defective part is a foreign matter attached to the display panel or a dark spot of the display panel;
And an inspection step of determining the quality of the display panel using different reference values depending on whether the defective part is a foreign object or a dark spot.

FIG. 1 is a cross-sectional view showing an example of a liquid crystal display panel. FIG. 2 is a block diagram showing the inspection apparatus according to the first embodiment. FIG. 3 is a schematic diagram illustrating the optical system of the inspection apparatus according to the first embodiment (part 1). FIG. 4 is a schematic diagram illustrating the optical system of the inspection apparatus according to the first embodiment (part 2). 5A and 5B are partially enlarged views of an image formed on the camera by the optical system. FIG. 6 is a schematic diagram illustrating an example in which a foreign object and a dark spot cannot be identified. FIG. 7 is a schematic diagram showing a structure when the interval between the reflecting mirrors is changed in the inspection apparatus according to the first embodiment. FIG. 8 is a schematic diagram showing the optical system of the inspection apparatus according to the second embodiment (No. 1). FIG. 9 is a schematic diagram showing the optical system of the inspection apparatus according to the second embodiment (No. 2). FIG. 10 is a block diagram showing an inspection apparatus according to the third embodiment. FIG. 11 is a schematic diagram illustrating an optical system of the inspection apparatus according to the third embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1, 2 ... Reflective mirror, 1a ... 1st reflective mirror, 1b ... 2nd reflective mirror, 2a ... 3rd reflective mirror, 2b ... 4th reflective mirror, 3, 4 ... Light-shielding plate, 3a ... 1st light-shielding plate, 3b ... 2nd light-shielding plate, 5, 5a, 5b ... Imaging lens, 10, 30 ... Inspection apparatus, 11, 11a, 11b ... Camera, 12 ... Camera drive part, 13 ... Optical system drive part, 14 ... Sample stage drive part , 15 ... Sample stage, 16 ... Control part, 17 ... Display part, 18, 21, 31 ... Optical system, 98 ... Dark spot, 99 ... Foreign matter, 100 ... Liquid crystal display panel, 101, 104 ... Transparent substrate, 102 ... Liquid crystal Layer 103 ... Color filter layer 105 ... Optical film.

Claims (5)

An optical system for projecting the surface of the display panel from two or more different viewing angles;
An imaging unit that acquires an image formed by the optical system as a pixel image;
Detecting a defective part whose luminance is lower than a predetermined value from the pixel image and comparing the defective part of the pixel image projected from different directions, whether the defective part adheres to the display panel or the display panel A display panel inspection apparatus, comprising: a control unit that determines whether there is a dark spot.   The control unit compares the color arrangement of the peripheral pixels of the defective part in a plurality of the pixel images, and if the color arrangement of the peripheral pixels of the defective part is different, the foreign matter adhered to the display panel 2. The display panel inspection apparatus according to claim 1, wherein if the color arrangement of peripheral pixels of the defective part is the same, the defective part is determined as a dark spot of the display panel. Imaging the surface of the display panel from two or more different directions to obtain a plurality of pixel images;
Detecting a defect site having a luminance lower than a specified value from the pixel image;
And comparing the defect sites in the plurality of pixel images to determine whether the defect site is a foreign matter adhering to the display panel or a dark spot of the display panel. . The step of determining whether the defective part is a foreign object or a dark spot is performed by comparing the color arrangement of peripheral pixels of the defective part with two or more of the pixel images,
When the color arrangement of the surrounding pixels of the defective part is different, the defective part is determined as a foreign matter attached to the display panel,
The display panel inspection method according to claim 3, wherein when the color arrangement of surrounding pixels of the defective part is the same, the defective part is determined as a dark spot of the display panel. Forming a display panel with an optical film attached thereto;
Capturing a plurality of pixel images by imaging the surface of the display panel from two or more different directions with respect to the surface of the display panel;
Detecting a defect site having a luminance lower than a specified value from the pixel image;
Comparing the color arrangement of the peripheral pixels of the defective part in a plurality of the pixel images to determine whether the defective part is a foreign matter attached to the display panel or a dark spot of the display panel;
And an inspection step of determining the quality of the display panel using different reference values depending on whether the defective part is a foreign object or a dark spot.

Images