阅读说明：本技术 检查装置 (Inspection apparatus ) 是由 堀田浩司 于 2019-06-11 设计创作，主要内容包括：检查装置20包括至少具有接收自多个像素(周期性检查对象物)PX有周期地并列地设置的主液晶面板(检查对象基板)10M的光的光接收元件25、以及用以在光接收元件25使光成像的成像部件26,并摄影与像素PX有关的图像的照相机(摄影部)21；经由将通过照相机21摄影的图像与参照图像进行比较,判定像素PX的好坏的判定部31；经由使光接收元件25与成像部件26相对位移,或者使主液晶面板10M与照相机21相对位移,将照相机21的光学分解能的数值调整成像素PX的周期的整数分之一的分解能调整部32。(The inspection apparatus 20 includes a camera (image pickup section) 21 which has at least a light receiving element 25 which receives light from a main liquid crystal panel (inspection target substrate) 10M in which a plurality of pixels (periodic inspection target objects) PX are periodically arranged in parallel, and an image pickup device 26 which images the light on the light receiving element 25, and which picks up an image relating to the pixels PX; a determination unit 31 for determining whether or not the pixel PX is good by comparing the image captured by the camera 21 with a reference image; and a resolution adjusting unit 32 for adjusting the value of the optical resolution of the camera 21 to be an integral fraction of the period of the pixel PX by relatively displacing the light receiving element 25 and the imaging unit 26 or relatively displacing the main liquid crystal panel 10M and the camera 21.)

1. An inspection apparatus, characterized in that,

the method comprises the following steps:

an imaging unit having at least a light receiving element for receiving light from a plurality of inspection target substrates arranged in parallel in a periodic manner and an imaging device for imaging the light on the light receiving element, and imaging an image of the periodic inspection target;

a determination unit that determines whether the periodic inspection object is good or bad by comparing the image captured by the imaging unit with a reference image; and

and a resolution adjustment unit configured to adjust a value of resolution of the imaging unit to be an integer fraction of a period of the periodic inspection object by relatively displacing the light receiving element and the imaging member or by relatively displacing the inspection target substrate and the imaging unit.

2. The inspection device of claim 1,

the imaging section is constituted by a plurality of lenses;

the resolution adjustment unit relatively displaces the plurality of lenses with respect to the light receiving element.

3. The inspection device of claim 1,

the method comprises the following steps:

an imaging moving unit that is attached to the inspection target substrate and moves the imaging unit in one direction with respect to the inspection target substrate;

the decomposition adjustable unit relatively displaces the imaging moving unit together with the imaging unit in a direction of moving closer to or away from the inspection target substrate.

4. The inspection apparatus according to any one of claims 1 to 3,

the method comprises the following steps:

an imaging moving unit that is attached to the inspection target substrate and moves the imaging unit in one direction with respect to the inspection target substrate; and

and a resolution adjusting unit configured to adjust a resolution of the image captured by the imaging unit by varying at least one of a moving speed of the imaging unit by the imaging moving unit and a sampling speed of the light receiving element.

5. The inspection apparatus according to any one of claims 1 to 3,

the method comprises the following steps:

an imaging moving unit that is attached to the inspection target substrate and moves the imaging unit in one direction with respect to the inspection target substrate; and

and an angle adjusting unit configured to adjust an angular difference that may occur between a moving direction of the imaging unit by the imaging moving unit and an arrangement direction of the plurality of periodic inspection objects by relatively displacing the imaging unit and the inspection target substrate.

6. The inspection device of claim 5,

the angle adjusting unit relatively displaces the inspection target substrate in the moving direction and in a direction orthogonal to the moving direction with respect to the imaging unit.

7. The inspection apparatus according to any one of claims 1, 2, 3, and 6,

the method comprises the following steps:

and a position adjustment unit configured to, when the inspection target substrate is divided into a plurality of inspection target regions in which the plurality of periodic inspection targets are arranged, and position adjustment indicators are provided in the plurality of inspection target regions, image the plurality of periodic inspection targets arranged in the inspection target regions before the plurality of periodic inspection targets are imaged by the imaging unit, and perform position adjustment of the inspection target substrate based on the image of the position adjustment indicators.

Technical Field

The present invention relates to an inspection apparatus.

Background

Conventionally, an example of an inspection apparatus for inspecting a pattern or the like on a wafer is known and described in patent document 1 below. In a method and an apparatus for inspecting a defect of a pattern formed on a test piece, the test piece is a so-called photomask, the design data of the pattern is compared with an acquired image pattern, the inspection is performed by comparing the acquired image with a design pattern created when the photomask is created, an image of the photomask (hereinafter, referred to as a wafer image) is formed by a stepper used when the pattern is actually formed on the wafer by the design data, the design data is converted by an appropriate method, and the actually measured acquired image is converted into the wafer image by an appropriate conversion method, and the two are compared to detect the defect.

Disclosure of Invention

Technical problem to be solved by the invention

According to the inspection apparatus described in patent document 1, the pattern on the wafer is created from the image obtained by the inspection apparatus, and only the defect that is a problem on the actual wafer can be extracted and inspected. However, when the resolution (optical resolution) of the imaging section for obtaining the image pattern interferes with the cycle of the pattern to be inspected, interference fringes called moire may be generated, and a defect may be erroneously detected due to the interference fringes.

The present invention has been made in view of the above circumstances, and an object thereof is to suppress generation of erroneous detection of a defect.

Means for solving the problems

(1) In one embodiment of the present invention, an inspection apparatus includes an imaging unit including at least a light receiving element for receiving light from an inspection target substrate on which a plurality of periodic inspection targets are periodically arranged in parallel, and an imaging means for imaging the light on the light receiving element, and imaging an image of the periodic inspection targets; comparing the image photographed by the photographing part with a reference image; a determination unit for determining whether the object to be periodically inspected is good or bad; and a resolution adjusting unit for adjusting the resolution of the imaging unit to a value that is an integer fraction of the period of the periodic inspection target by relatively displacing the light receiving element and the imaging member or relatively displacing the inspection target substrate and the imaging unit.

In this case, light from the inspection target substrates, which are periodically arranged in parallel with the plurality of periodic inspection targets, is imaged on the light receiving element by the imaging means, and the light is received by the light receiving element. Thus, the imaging unit can image an image of the periodic inspection object. The determination unit determines whether the object to be periodically inspected is good or bad by comparing the image photographed by the photographing unit with the reference image. The reference image may be obtained by imaging a periodic inspection object to be compared by an imaging unit, or may be set in advance based on design data of the periodic inspection object. Here, since a plurality of periodic inspection objects are arranged in parallel in a periodic manner on the inspection object substrate, when the period of the periodic inspection object and the resolution of the imaging unit can interfere with each other, interference fringes called moire fringes are generated, and false detection of defects may occur. In this case, the resolution adjustment unit can adjust the numerical value of the resolution of the imaging unit to an integer fraction of the period of the periodic inspection object by relatively displacing the light receiving element and the imaging member or relatively displacing the inspection target substrate and the imaging unit, and thus the period of the periodic inspection object and the resolution of the imaging unit can be made less likely to interfere with each other. This suppresses generation of false detection of defects due to moire.

(2) In addition to the configuration of the above (1), an embodiment of the present invention is such that the imaging means is constituted by a plurality of lenses; and an inspection device in which the resolution adjustment unit relatively displaces the plurality of lenses with respect to the light receiving element.

(3) In addition to the configuration of the above (1), an embodiment of the present invention includes a photographing unit that is attached to the inspection target substrate and moves the photographing unit in one direction with respect to the inspection target substrate; and an inspection device in which the resolution adjusting unit relatively displaces the imaging moving unit together with the imaging unit in a direction of moving closer to or away from the substrate to be inspected.

(4) In addition to the configuration of any one of the above (1) to (3), an embodiment of the present invention includes an imaging moving unit to which the imaging unit is attached and which moves the imaging unit in one direction with respect to the inspection target substrate; and an inspection device for adjusting a resolution adjustment unit for adjusting a resolution of the image captured by the imaging unit by varying at least one of a moving speed of the imaging unit by the imaging moving unit and a sampling speed of the light receiving element.

(5) In addition to the configuration of any one of the above (1) to (4), an embodiment of the present invention includes an imaging moving unit that has the imaging unit mounted thereon and moves the imaging unit in one direction with respect to the inspection target substrate; and an angle adjusting unit for adjusting an angular difference that may occur between a moving direction of the imaging unit by the imaging moving unit and an arrangement direction of the plurality of periodic inspection objects by relatively displacing the imaging unit and the inspection target substrate.

(6) In addition to the configuration of (5), the present invention is directed to an inspection apparatus in which the angle adjusting unit relatively displaces the inspection target substrate in the moving direction and in a direction orthogonal to the moving direction with respect to the imaging unit.

(7) In addition to the configuration of any one of (1) to (6), an embodiment of the present invention is an inspection apparatus including a position adjustment unit configured to, when the inspection target substrate is divided into a plurality of inspection target regions in which a plurality of the periodic inspection targets are arranged, and a position adjustment index unit is provided in each of the plurality of inspection target regions, image an image related to the position adjustment index unit before the plurality of the periodic inspection targets arranged in the inspection target regions are imaged by the imaging unit, and perform position adjustment of the inspection target substrate based on the image related to the position adjustment index unit.

Effects of the invention

According to the present invention, generation of erroneous detection of a defect can be suppressed.

Drawings

Fig. 1 is a plan view of a liquid crystal panel and the like according to embodiment 1 of the present invention.

Fig. 2 is a circuit diagram showing an arrangement of pixels in a display region of a liquid crystal panel.

Fig. 3 is a plan view of the inspection apparatus.

Fig. 4 is a plan view of the inspection apparatus.

Fig. 5 is a block diagram showing an electrical configuration of the inspection apparatus.

Fig. 6 is a diagram showing a schematic relationship between a camera constituting an inspection apparatus and a main liquid crystal panel.

Fig. 7 is a diagram showing a state in which an imaging member constituting a camera is moved relative to a light receiving element.

Fig. 8 is a block diagram showing an electrical configuration of an inspection apparatus according to embodiment 2 of the present invention.

Fig. 9 is a plan view of the inspection apparatus.

Fig. 10 is a plan view of the arrangement of color filters in the CF substrate constituting the liquid crystal panel according to embodiment 3 of the present invention.

Fig. 11 is a plan view for explaining a positional relationship among pixels where spacers are arranged, a camera, and a camera moving unit.

Fig. 12 is a block diagram showing an electrical configuration of the inspection apparatus.

Fig. 13 is a plan view of the inspection apparatus.

Fig. 14 is a plan view showing the configuration of each terminal section of the liquid crystal panel according to embodiment 4 of the present invention.

Fig. 15 is a plan view of the inspection apparatus.

Fig. 16 is a block diagram showing an electrical configuration of the inspection apparatus.

Detailed Description

(embodiment mode 1)

Embodiment 1 of the present invention is explained with reference to fig. 1 to 7. In the present embodiment, an inspection apparatus 20 for inspecting a liquid crystal panel (display panel) 10 will be described as an example. Further, an X axis, a Y axis, and a Z axis are shown in a part of each drawing, and each axis direction is depicted as a direction shown in each drawing. The vertical direction is defined with reference to fig. 1, and the upper side of the same figure is the front side and the lower side of the same figure is the back side.

First, the configuration of the liquid crystal panel 10 to be inspected by the inspection apparatus 20 will be described. The liquid crystal panel 10 displays an image by irradiation light emitted from a backlight device (illumination device) not shown. The general liquid crystal panel 10 has a square shape as shown in fig. 1, and has a longitudinal direction of X axis, a short side direction of Y axis, and a thickness direction of Z axis. The liquid crystal panel 10 is a display area AA for displaying an image in a central portion of the screen, and a non-display area NAA for not displaying an image in a frame-shaped outer peripheral portion of the screen which is located in the display area AA. In addition, a range enclosed by a broken line in fig. 1 is a display area AA. The liquid crystal panel 10 is configured to sandwich a liquid crystal layer including liquid crystal molecules, which are substances having optical characteristics changing with application of an electric field, between a pair of glass substrates 10A and 10B that are substantially transparent and have excellent light transmittance. Of the pair of substrates 10A, 10B, a CF substrate (counter substrate) 10A is disposed on the front surface side, and an array substrate (active matrix substrate, TFT substrate) 10B is disposed on the rear surface side. The CF substrate 10A and the array substrate 10B are formed by laminating various films on the inner surface side of any one of the glass substrates. The array substrate 10B has a CF substrate non-overlapping portion 10B1 having a longer side dimension larger than the same dimension of the CF substrate 10A and not overlapping with the CF substrate 10A. The front surface side of the CF substrate non-overlapping portion 10B1 is not covered with the CF substrate 10A and is exposed to the outside, and components such as a driver (panel driving means) 11, a flexible substrate (signal transmission means) 12, and the like described below are mounted. In the CF substrate non-overlapping portion 10B1, various terminals (not shown in the present embodiment) are formed in the mounting area of the driver 11, the flexible substrate 12, and the like.

The driver 11 is formed of an LSI chip having a driving circuit therein, and as shown in fig. 1, cog (chip On glass) is mounted On the non-display area NAA, i.e., the CF substrate non-overlapping portion 10B 1. The driver 11 is disposed in a position close to the display area AA with respect to the flexible substrate 12 described later with respect to the Y-axis direction, and can process various signals transmitted through the flexible substrate 12. The flexible substrate 12 is formed by forming a plurality of wiring patterns (not shown) on a base material made of a synthetic resin material having insulation and flexibility (for example, a polyimide-based resin or the like), and one end side thereof is connected to the CF substrate non-overlapping portion 10B1 of the array substrate 10B, and the other end side thereof is connected to a control substrate (signal supply source) not shown. Various signals supplied from the control substrate are transmitted to the liquid crystal panel 10 via the flexible substrate 12, and are output to the display area AA through processing by the driver 11 in the non-display area NAA. The driver 11 and the flexible substrate 12 are electrically and mechanically connected to the CF substrate non-overlapping portion 10B1 via an Anisotropic Conductive Film (ACF) not shown.

As shown in fig. 2, a plurality of grid-shaped gate lines (scanning lines) 13 and a plurality of source lines (signal lines and data lines) 14 are provided on the inner surface side of the display area AA of the array substrate 10B, and a switching element TFT15 and a pixel electrode 16 are provided near the intersection of the lines. The gate lines 13 are connected to gate electrodes of the TFTs 15 extending in the X-axis direction in the cross sectional display area AA, and the source lines 14 are connected to source electrodes of the TFTs 15 extending in the Y-axis direction in the vertical sectional display area AA. The gate lines 13 are arranged side by side with a plurality of spaces therebetween in the Y-axis direction, and the source lines 14 are arranged with a plurality of spaces therebetween in the X-axis direction. The TFTs 15 and the pixel electrodes 16 are arranged in a planar manner such that a plurality of them are regularly arranged in a matrix (in a row-column manner) along the X-axis direction and the Y-axis direction, and the pixel electrodes 16 are connected to the drain electrodes of the TFTs 15. The TFT15 is driven based on a scanning signal supplied to the gate wiring 13, and charges the pixel electrode 16 with a potential based on an image signal (signal, data signal) supplied to the source wiring 14. On the other hand, although not shown, color filters of three colors of red (R), green (G), and blue (B) disposed so as to overlap each pixel electrode 16, a light shielding portion (black matrix) for separating adjacent color filters, and the like are provided on the inner surface of the display area AA of the CF substrate 10A. In this liquid crystal panel 10, the color filters of R, G, B arranged along the X-axis direction and the three pixel electrodes 16 facing the color filters constitute three-color pixels (periodic inspection objects) PX. The pixels PX are periodically arranged in the X-axis direction and the Y-axis direction at a predetermined arrangement pitch (period). A common electrode (not shown) made of the same transparent electrode material as the pixel electrode 16 and disposed to overlap the pixel electrode 16 with a space therebetween is provided on either the CF substrate 10A or the array substrate 10B. The liquid crystal panel 10 applies a predetermined electric field based on the potential difference generated between the common electrode and each pixel electrode 16, thereby displaying a predetermined color tone in each pixel PX.

A method of manufacturing the liquid crystal panel 10 will be described. The liquid crystal panel 10 is manufactured by manufacturing a CF substrate 10A and an array substrate 10B, respectively, and then interposing a liquid crystal layer between these substrates 10A and 10B and bonding them. More specifically, in the manufacture of the CF substrate 10A and the array substrate 10B, various films (metal films, insulating films, etc.) are patterned on any large-sized main glass substrate by a known photolithography method or the like. The main glass substrate has a plurality of CF substrates 10A and array substrates 10B arranged on the surface thereof. Then, a liquid crystal layer is interposed between and bonded to a main glass substrate having a plurality of CF substrates 10A and a main glass substrate having a plurality of array substrates 10B, thereby manufacturing a main liquid crystal panel 10M (inspection target substrate) shown in fig. 3. The manufactured main liquid crystal panel 10M is configured such that a plurality of (nine in the present embodiment) liquid crystal panels 10 are arranged in its plane, and then divided into a plurality of liquid crystal panels 10 by a dividing device. In fig. 3, each display area AA is illustrated as a square frame in the plurality of liquid crystal panels 10 included in the main liquid crystal panel 10M. The liquid crystal panel 10 thus manufactured is subjected to various inspections for detecting the presence or absence of defects in the manufacturing process. The inspection apparatus 20 for inspecting the main liquid crystal panel 10M before dividing the plurality of liquid crystal panels 10 will be described in detail below.

As shown in fig. 3, the inspection apparatus 20 according to the present embodiment is an automatic optical inspection Apparatus (AOI) that automatically performs lighting inspection of a plurality of pixels PX optically on the main liquid crystal panel 10M. The inspection apparatus 20 includes a camera (image pickup unit) 21 for picking up an image of the main liquid crystal panel 10M as an inspection object, a camera moving unit (image pickup moving unit) 22 for moving the camera 21 in the Y-axis direction, a panel holding unit (substrate holding unit) 23 for holding the main liquid crystal panel 10M, and a panel moving unit (substrate moving unit) 24 for moving the panel holding unit 23 in the X-axis direction together with the main liquid crystal panel 10M.

As shown in fig. 4, the camera 21 is disposed to face the main liquid crystal panel 10M in the Z-axis direction (the normal direction of the plate surface of the main liquid crystal panel 10M) with a space therebetween, and can photograph a predetermined range in the plate surface of the main liquid crystal panel 10M. More specifically, as shown in fig. 6, the camera 21 includes at least a light receiving element 25 that receives light from the main liquid crystal panel 10M, and an imaging unit 26 that images light from the main liquid crystal panel 10M on the light receiving element 25. The light receiving element 25 is disposed in an opposing shape with respect to the Z-axis direction imaging part 26 with respect to the main liquid crystal panel 10M interposed therebetween. The imaging member 26 is composed of at least two lenses 26A, 26B arranged in a space between the light receiving element 25 and the main liquid crystal panel 10M in the Z-axis direction so as to be aligned in the Z-axis direction, and the first lens 26 arranged on the front side is, for example, a biconvex lens, and the second lens 26B arranged on the back side is, for example, a biconcave lens.

As shown in fig. 3, the camera moving unit 22 includes a camera moving mechanism (not shown) which is fixedly disposed near the center in the X direction of the inspection apparatus 20 (panel moving unit 24) and which extends in the Y direction, which is the direction along the plate surface of the main liquid crystal panel 10M, and linearly moves the camera 21 in the Y direction, which is the extending direction of the camera. The camera moving mechanism may be composed of a combination of a guide rail, a ball screw and a motor, a linear motor, a timing belt and a motor, and the like. The panel holding portion 23 is arranged in plural so as to be held by suction, clamping, or the like in the vicinity of each of the four corners of the main liquid crystal panel 10M. The panel moving unit 24 extends in the direction along the plate surface of the liquid crystal panel 10M, i.e., in the X-axis direction, and crosses the camera moving unit 22. The panel moving unit 24 includes a holding unit moving mechanism (not shown) which is fixedly arranged in a pair near both ends of the inspection apparatus 20 so as to sandwich the main liquid crystal panel 10M from both sides in the Y-axis direction, and linearly moves the panel holding unit 23 along the X-axis direction which is the extending direction thereof. The holding portion moving mechanism has the same configuration as the camera moving mechanism described above.

As shown in fig. 5, the inspection apparatus 20 includes an illumination device 27 for reflection inspection or transmission inspection with respect to the main liquid crystal panel 10M, and an inspection display control unit 28 for controlling the driving of the main liquid crystal panel 10M and the illumination device 27 and displaying an image for inspection on each display area AA of the plurality of liquid crystal panels 10. The inspection apparatus 20 includes a memory 29 for storing an image or the like captured by the camera 21, a movement control unit 30 for controlling the driving of the camera moving unit 22 and the panel moving unit 24, a determination unit 31 for determining the quality of the pixel PX by reading out the image captured by the camera 21 and a reference image from the memory 29 and comparing them, an resolution adjustment unit 32 for adjusting the optical resolution (resolution) of the camera 21 by moving the imaging unit 26 with respect to the light receiving element 25, and a resolution adjustment unit 33 for adjusting the resolution of the image captured by the camera 21. The control units 28 and 30, the determination unit 31, and the resolution adjustment unit 32 may be a single CPU. Although not shown, the inspection apparatus 20 includes an auxiliary panel moving unit that supports the main liquid crystal panel 10M from the back side in the Z-axis direction via the main liquid crystal panel 10M and assists the movement of the main liquid crystal panel 10M passing through the panel moving unit 24.

Here, the pixels PX to be inspected by the inspection apparatus 20 are arranged so as to be repeatedly arranged at a fixed period in the X-axis direction and the Y-axis direction, and the cameras 21 for capturing the pixels PX are regularly arranged with light receiving elements having a fixed size, and the size of the image formed by the light receiving elements is optical resolution. Therefore, if interference occurs between the period of the pixels PX and the optical resolution of the camera 21, interference fringes called moire fringes are generated, and due to this, the detection sensitivity of defects may be reduced and false detection may occur. Specifically, when moire is generated, the luminance of the specific pixel PX is higher or lower than the target value, and if the pixel PX is not normal, the determination unit 31 may make an erroneous determination that a defect is generated. In order to avoid erroneous detection for the above reasons, if the threshold value, which is the criterion for determining whether or not a defect is present, is set to be large, the performance (detection sensitivity) is degraded. Here, the inspection apparatus 20 according to the present embodiment includes an optical resolution adjusting unit 32 that adjusts the optical resolution of the camera 21 by moving the imaging unit 26 relative to the light receiving element 25, and the optical resolution adjusting unit 32 can adjust the value of the optical resolution of the camera 21 to be an integer multiple of the period of the pixels PX. Specifically, the resolution adjustment unit 32 adjusts the numerical value of the optical resolution of the camera 21 to be one-integer times the period of the pixels PX by relatively displacing the imaging unit 26 in the Z-axis direction with respect to the light receiving element 25 constituting the camera 21. In the present embodiment, the light receiving element 25 is fixed. In this case, interference between the period of the pixels PX and the optical resolution of the camera 21 is less likely to occur, and generation of false detection of defects due to moire can be suppressed. Further, since the resolution adjustment unit 33 can adjust the resolution of the image captured by the camera 21 by varying at least one of the movement speed of the camera 21 by the camera movement unit 22 and the sampling speed of the light receiving element 25, even if it is assumed that the generation of moire is problematic regardless of the adjustment of the optical resolution of the camera 21 by the resolution adjustment unit 32, the generation of erroneous detection of defects due to moire is more appropriately suppressed if the resolution adjustment unit 33 is set to reduce the resolution of the image.

The inspection apparatus 20 according to the present embodiment has the above-described structure, and a method of inspecting the main liquid crystal panel 10M using the inspection apparatus 20 will be described next. First, as shown in fig. 3, the main liquid crystal panel 10M is held by each panel holding portion 23. In this state, the main liquid crystal panel 10M is moved in the X-axis direction by the panel moving unit 24, and the camera 21 is moved in the Y-axis direction by the camera moving unit 22, so that the image is captured by the camera 21 by the pixel PX of the inspection target in the main liquid crystal panel 10M entering the field of the camera 21. The photographed image is stored in the storage unit 29. When the photographing of the pixel PX to be inspected is completed, the camera moving unit 22 moves the camera 21 in the Y-axis direction, and the camera 21 photographs the next pixel PX to be inspected. By repeating these operations, the row of pixels PX arranged in the Y-axis direction on the main liquid crystal panel 10M can be photographed as a whole. When the above-described shooting of the pixel PX row is completed, the main liquid crystal panel 10M is moved in the X-axis direction by the panel moving unit 24, and the pixel PX row to be the next shooting target is shot by the camera 21 after passing through the boundary of the camera 21. By repeating this, it is possible to sequentially photograph a plurality of pixel PX rows arranged in the X-axis direction, and photograph and inspect the pixels PX arranged in the entire main liquid crystal panel 10M.

The determination unit 31 determines whether or not the pixel PX is good based on the image stored in the storage unit 29. At this time, the determination unit 31 extracts a luminance value from the image of the pixel PX to be determined, extracts a luminance value from the reference image, and calculates the difference between these luminance values. The determination unit 31 determines that the pixel PX to be determined is good when the obtained difference is lower than a predetermined threshold value, and determines that the pixel PX to be determined is bad when the difference is higher than the threshold value. The reference image may be obtained by capturing a pixel PX to be compared with the camera 21, or may be set in advance based on design data of the pixel PX. In any case, the reference image and the threshold are stored in the storage unit 29.

In the present embodiment, before the determination of the pixel PX by the determination unit 31 as described above, the adjustment related to the optical resolution of the camera 21 is performed by the resolution adjusting unit 32. As shown in fig. 6 and 7, the resolution adjusting unit 32 moves the imaging unit 26 in the Z-axis direction with respect to the light receiving element 25 based on the period of the pixels PX, and adjusts the value of the optical resolution of the camera 21 so as to be an integer fraction of the period of the pixels PX. When fig. 6 and 7 are compared, the first lens 26A of the two lenses 26A and 26B constituting the imaging member 26 is arranged in the vicinity of the light receiving element 25 (in the vicinity of the second lens 26B) in fig. 6, and is arranged in the vicinity of the light receiving element 25 (in the vicinity of the second lens 26B) in fig. 7. The second lens 26B is arranged in the vicinity of the main liquid crystal panel 10M (in the vicinity of the first lens 26A) in fig. 6, and in the vicinity of the main liquid crystal panel 10M (in the vicinity of the first lens 26A) in fig. 7. The numerical value of the optical resolution of the camera 21 can be adjusted by moving the two lenses 26A and 26B constituting the imaging unit 26 in the Z-axis direction and changing the positional relationship with the light receiving element 25. Accordingly, the value of the optical resolution of the camera 21 can be set to be an integer fraction of the period of the pixel PX, and therefore interference between the period of the pixel PX and the optical resolution of the camera 21 can be suppressed. Therefore, the luminance value extracted by the determination unit 31 from the image of the pixel PX to be determined is less affected by the moire, and thus the pixel PX can be appropriately determined. As a result, generation of false detection of defects due to moire can be suppressed.

By adjusting the optical resolution of the camera 21 by the resolution adjustment portion 32 in this way, although the generation of moire can be suppressed, there is a possibility that the generation of moire may occur regardless of the adjustment of the optical resolution of the camera 21 by the resolution adjustment portion 32 according to the inspection condition or the like. In such a case, at least one of the moving speed of the camera 21 by the camera moving unit 22 and the sampling speed of the light receiving element 25 may be varied by the resolution adjusting unit 33 to reduce the resolution of the image captured by the camera 21. In this case, it is possible to more appropriately suppress generation of erroneous detection of a defect due to moire.

The inspection apparatus 20 of the present embodiment described above includes a camera (imaging section) 21 which has at least a light receiving element 25 which receives light from a main liquid crystal panel (inspection target substrate) 10M in which a plurality of pixels (periodic inspection target objects) PX are arranged in parallel with a period, an imaging means 26 which images light at the light receiving element 25, and which images an image relating to the pixels PX, a determination section 31 which determines the quality of the pixels PX by comparing the image imaged by the camera 21 with a reference image, and a resolution adjustment section 32 which adjusts the value of the optical resolution of the camera 21 to be one integral multiple of the period of the pixels PX by relatively displacing the light receiving element 25 and the imaging means 26.

In this way, light from the main liquid crystal panel 10M in which the plurality of pixels PX are periodically arranged in parallel is imaged on the light receiving element 25 by the imaging device 26, and the light is received by the light receiving element 25. Thereby, the camera 21 can photograph an image related to the pixel PX. The determination unit 31 determines whether or not the pixel PX is good by comparing the image captured by the camera 21 with the reference image. The reference image may be obtained by capturing a pixel PX to be compared with the camera 21, or may be set in advance based on design data of the pixel PX. Here, since there is a possibility that a plurality of pixels PX are arranged in parallel in a periodic manner in the main liquid crystal panel 10M, when the period of the pixels PX interfere with the optical resolution of the camera 21, interference fringes called moire fringes are generated, and there is a possibility that erroneous detection of defects due to the interference fringes is caused. In this regard, the resolution adjusting unit 32 can adjust the numerical value of the optical resolution of the camera 21 to be an integer fraction of the period of the pixel PX by relatively displacing the light receiving element 25 and the imaging member 26, and therefore interference between the period of the pixel PX and the optical resolution of the camera 21 can be made less likely to occur. This suppresses generation of false detection of defects due to moire.

The imaging unit 26 is composed of a plurality of lenses 26A and 26B, and the resolving power adjusting unit 32 relatively displaces the plurality of lenses 26A and 26B with respect to the light receiving element 25. In this case, the numerical value of the optical resolution of the camera 21 is adjusted so as to be an integral fraction of the period of the pixels PX by moving the plurality of lenses 26A and 26B constituting the imaging unit 26 relative to the light receiving element 25 by the resolution adjustment unit 32.

The liquid crystal display device further includes a camera moving unit 22 to which the camera 21 is attached and which moves the camera 21 in one direction with respect to the main liquid crystal panel 10M, and a resolution adjusting unit 33 which adjusts the resolution of an image captured by the camera 21 by varying at least one of the moving speed of the camera 21 by the camera moving unit 22 and the sampling speed of the light receiving element 25. In this way, the pixels PX can be continuously inspected by moving the camera 21 in one direction with respect to the main liquid crystal panel 10M by the camera moving unit 22 and photographing the pixels PX by the camera 21. Since the resolution adjusting unit 33 can adjust the resolution of the image captured by the camera 21 by varying at least one of the moving speed of the camera 21 by the camera moving unit 22 and the sampling speed of the light receiving element 25, for example, when moire is suspected, the resolution of the image is changed, and thus generation of false detection of a defect due to moire can be more appropriately suppressed.

(embodiment mode 2)

Embodiment 2 of the present invention will be described with reference to fig. 8 or 9. In embodiment 2, the second camera moving unit 34 is added. Note that the same structure, operation, and effects as those of embodiment 1 described above are not described repeatedly.

As shown in fig. 8, the inspection apparatus according to the present embodiment includes a second camera moving unit 34 that moves a camera moving unit 122. As shown in fig. 9, the second camera moving unit 34 is configured to move the camera 121 in the Y-axis direction up and down in the Z-axis direction (a direction toward and away from the camera 21 with respect to the main liquid crystal panel 110M) together with the camera 121. The camera 121 changes a positional relationship in a manner to approach or separate from the main liquid crystal panel 110M with the movement of the camera moving part 122 by the second camera moving part 34. This changes the optical resolution of the camera 121. As shown in fig. 8, the second camera moving unit 34 is driven under control of the resolution adjusting unit 132. In other words, the optical resolution of the camera 121 can be adjusted to be an integer fraction of the period of the pixels by controlling the driving of the second camera moving unit 34 via the resolution adjusting unit 132. In fig. 8, the resolution adjustment unit 33 described in embodiment 1 is not shown.

The inspection apparatus according to the present embodiment described above includes a camera 121 which has at least a light receiving element for receiving light from a main liquid crystal panel 110M in which a plurality of pixels are arranged in parallel with a cycle, an imaging means for imaging light on the light receiving element, and captures an image relating to the pixel, a determination unit 131 for determining whether the pixel is good or bad by comparing the image captured by the camera 121 with a reference image, and an energy resolving adjustment unit 132 for adjusting the value of the optical resolving energy of the camera 121 to be one integral fraction of the cycle of the pixel PX by relatively displacing the main liquid crystal panel 110M and the camera 26.

In this case, light from the main liquid crystal panel 110M in which a plurality of pixels are periodically arranged in parallel is received by the light receiving element by imaging the light on the light receiving element by the imaging means. Thereby, the camera 121 can photograph an image relating to the pixels. The determination unit 131 determines whether or not a pixel is good by comparing the image captured by the camera 121 with the reference image. The reference image may be obtained by photographing a pixel to be compared with the reference image with the camera 121, or may be set in advance based on design data of the pixel or the like. Here, since a plurality of pixels are periodically arranged in parallel in the main liquid crystal panel 110M, when the period of the pixels interferes with the optical resolution of the camera 121, interference fringes called moire fringes are generated, and there is a possibility that a defect is erroneously detected due to the interference fringes. In this regard, the resolution adjusting unit 132 can adjust the numerical value of the optical resolution of the camera 21 to be an integer fraction of the period of the pixel by relatively displacing the main liquid crystal panel 110M and the camera 121, and therefore interference between the period of the pixel and the optical resolution of the camera 121 can be made less likely to occur. This suppresses generation of false detection of defects due to moire.

The camera 121 is attached to a camera moving unit 122 that moves the camera 121 in one direction with respect to the main liquid crystal panel 110M, and the resolution adjusting unit 132 relatively displaces the camera moving unit 122 in a direction of approaching and separating together with the camera 121 with respect to the main liquid crystal panel 110M. In this way, the pixels can be continuously inspected by moving the camera 121 in one direction with respect to the main liquid crystal panel 110M by the camera moving unit 122 and photographing the pixels by the camera 121. The camera moving unit 122 is relatively moved in the direction of moving closer to and away from the main liquid crystal panel 110M together with the camera 121 by the resolution adjusting unit 132, and the value of the optical resolution of the camera 121 is adjusted so as to be an integer fraction of the period of the pixel.

(embodiment mode 3)

Embodiment 3 of the present invention is explained with reference to fig. 10 to 13. In embodiment 3, the configuration described in embodiment 1 above is shown with the addition of the second panel moving unit 35 and the angle adjusting unit 36. Note that the same structure, operation, and effects as those of embodiment 1 described above are not described repeatedly.

As shown in fig. 10, the liquid crystal panel according to the present embodiment includes a spacer 17 for fixedly maintaining a gap (thickness of the liquid crystal layer, cell gap) between the pair of substrates. The spacer 17 is disposed so as to overlap the color filter 18 of a specific color (specifically, blue, which has a lower relative visibility than green) among the three color filters 18 included in the CF substrate constituting the liquid crystal panel. Since the color filter 18 constitutes the pixel PX together with the pixel electrode on the array substrate side, the spacer 17 is arranged to overlap the pixel PX of a specific color. The spacers 17 are not arranged to overlap all the pixels PX that represent blue, but are selectively arranged to overlap the pixels PX that represent blue with a fixed period. Since the spacer 17 is made of a substantially transparent resin material and is disposed between the pair of substrates so as to penetrate the liquid crystal layer, it causes a shadow to be generated in the pixel PX. Therefore, in some cases, even when the pixels PX having the spacers 17 arranged therein and the pixels PX not having the spacers 17 arranged therein are displayed with the same color tone, a difference in luminance occurs in the pixels PX of blue. Specifically, the pixel PX having the spacer 17 tends to have a lower luminance. Therefore, if the pixels PX where the spacers 17 are arranged and the pixels PX where the spacers 17 are not arranged are inspected without distinction, there is a possibility that erroneous detection of a defect occurs.

Here, in the present embodiment, the inspection is performed so as to selectively inspect the pixels PX where the spacers 17 are arranged. Here, since the period of the pixels PX on which the spacers 17 are arranged is longer than the period of the pixels PX, the distance for moving the camera 222 between the pixels PX on which the spacers 17 to be photographed are arranged tends to be long. Therefore, when the arrangement direction of the pixels PX on which the spacers 17 are arranged is inclined at the angle θ with respect to the axis (Y-axis direction) of the camera moving unit 223 due to a manufacturing error of the main liquid crystal panel 210M, as shown in fig. 11, if the camera 222 is moved along the axis of the camera moving unit 223, the camera 222 may erroneously photograph the pixels PX on which the spacers 17 are not arranged. In contrast, as shown in fig. 12, the inspection apparatus 220 according to the present embodiment includes a second panel moving unit 35 that moves the main liquid crystal panel 210M in the Y-axis direction (the moving direction of the camera 222) and the X-axis direction (the direction orthogonal to the moving direction of the camera 222), and an angle adjusting unit 36 that controls the movement of the main liquid crystal panel 210M by the second panel moving unit 35 to adjust an angular difference that may occur between the moving direction of the camera 221 and the arrangement direction of the pixels PX on which the spacers 17 are arranged. As shown in fig. 13, the second panel moving portion 35 can press each corner portion of the four corners of the main liquid crystal panel 210M in the X-axis direction and the Y-axis direction. The second panel moving portions 35 are disposed two at each corner portion of each main liquid crystal panel 210M, and by pressing each corner portion in the X-axis direction and the Y-axis direction at a predetermined timing, the main liquid crystal panel 210M can be displaced in the X-axis direction and the Y-axis direction, and as a result, the main liquid crystal panel 210M can be rotated. The pressing of the main liquid crystal panel 210M by the second panel moving portion 35 is suppressed via the angle adjusting portion 36, and the rotation angle of the main liquid crystal panel 210M is adjusted, so that the angular difference generated between the moving direction of the camera 221 and the arrangement direction of the pixels PX in which the spacers 17 are arranged can be reduced, and in some cases, the angular difference can be eliminated. This can appropriately suppress the generation of erroneous detection of a defect due to the above-described angle difference. In fig. 12, the resolution adjustment unit 33 described in embodiment 1 is not shown.

According to the present embodiment described above, the present embodiment includes the camera moving unit 222 in which the camera 221 is attached and the camera 221 is moved in one direction with respect to the main liquid crystal panel 210M, and the angle adjusting unit 36 that adjusts an angular difference that may occur between the moving direction of the camera 221 by the camera moving unit 222 and the arrangement direction of the plurality of pixels PX by relatively displacing the camera 221 and the main liquid crystal panel 210M. In this way, the pixels PX can be continuously inspected by moving the camera 221 in one direction with respect to the main liquid crystal panel 210M by the camera moving unit 222 and capturing images of the pixels PX by the camera 221. Here, as the period of the plurality of pixels PX becomes longer, an angular difference tends to be more likely to occur between the moving direction of the camera 221 by the camera moving unit 222 and the arrangement direction of the plurality of pixels PX. In this regard, even if an angular difference is generated between the moving direction of the camera 221 by the camera moving unit 222 and the arrangement direction of the plurality of pixels PX, the angular difference can be adjusted by relatively displacing the camera 221 and the main liquid crystal panel 210M, and thus the generation of the erroneous detection of the defect due to the same angular difference can be appropriately suppressed. In particular, the present invention is suitable for a case where the period of the plurality of pixels PX is long.

The angle adjusting unit 36 displaces the main liquid crystal panel 210M relative to the camera 221 in the moving direction and in the direction orthogonal to the moving direction. In this way, it is possible to adjust the angular difference that may occur between the direction of movement of the camera 221 by the camera moving unit 222 and the direction in which the plurality of pixels PX are arranged, by relatively displacing the main liquid crystal panel 210M with respect to the camera 221 by the angle adjusting unit 36 in the direction perpendicular to the direction of movement and the direction in which the camera 221 moves by the camera moving unit 222.

(embodiment mode 4)

Embodiment 4 of the present invention is explained with reference to fig. 14 to 16. In embodiment 4, the configuration described in embodiment 1 above shows the second panel moving unit 335 and the position adjusting unit 37 added. Note that the same structure, operation, and effects as those of embodiment 1 described above are not described repeatedly.

As shown in fig. 14, the liquid crystal panel 310 according to the present embodiment includes a plurality of terminal portions 19 arranged in a plurality of cycles in the X-axis direction in the mounting region of the driver 311 and the flexible substrate 312. The terminal portion 19 includes a driver terminal portion 19A connected to a terminal on the driver 311 side in a mounting region of the driver 311, and a flexible board terminal portion 19B connected to a terminal on the flexible board 312 side in a mounting region of the flexible board 312. The driver terminal unit 19A includes an input terminal unit 19A1 for inputting signals to the driver 311 and an output terminal unit 19A2 for outputting signals received from the driver 311, and the latter is smaller than the former in size and arrangement pitch. These terminal portions 19a1, 19a2, and 19B are arranged in different periods for each kind, and any one of these periods is much larger than the period of the pixel. Therefore, the inspection device 320 receives the inspection for each type through the terminal units 19a1, 19a2, and 19B, and the resolution adjusting unit 332 adjusts the optical resolution of the camera 321 at this time, thereby suppressing the generation of the error detection of the defect caused by moire in the display region (see fig. 15 and 16).

However, in the inspection of the terminal portion 19, as shown in fig. 15, the inspection may be performed by comparing images of the terminal portion 19 photographed by the camera 321 between a plurality of liquid crystal panels (inspection target regions) 310 provided in the main liquid crystal panel 310M. In this case, in order to photograph the terminal section 19 provided in the liquid crystal panel 310 to be inspected and the terminal section 19 provided in the liquid crystal panel 310 to be compared, it is necessary to move the camera 321 and the main liquid crystal panel 310M by a distance much larger than the pixel cycle and the cycle of the same kind of terminal section 19. As described above, the camera 321 and the main liquid crystal panel 310M may be displaced from each other by a long distance. Therefore, in the present embodiment, the position adjustment indicator 40 is provided individually on the plurality of liquid crystal panels 310 included in the main liquid crystal panel 310M. Although the position adjustment indicator 40 is illustrated with a numeral "5" as an example in the present embodiment, the specific indication method of the position adjustment indicator 40 may be other numerals, characters, and the like. As shown in fig. 16, the inspection apparatus 320 includes a second panel moving unit 335 for moving the main liquid crystal panel 310M in the Y-axis direction (the moving direction of the camera 321) and the X-axis direction (the direction orthogonal to the moving direction of the camera 321), and a position adjusting unit 37 for taking an image of the position adjustment indicator 40 by the camera 321 and adjusting the position of the main liquid crystal panel 310M based on the image of the position adjustment indicator 40. The second panel moving section 335 is the same as described in embodiment 2. The position adjusting unit 37 controls the driving of the second panel moving unit 335 based on the image of the position adjustment indicator 40 captured by the camera 321, thereby making it possible to rationalize the position of the main liquid crystal panel 310M in the X-axis direction and the Y-axis direction. The position adjustment unit 37 adjusts the position of the main liquid crystal panel 310M before each inspection of the terminal sections 19 provided in the liquid crystal panels 310, and even if the period of the terminal sections 19 is increased due to the distance between the liquid crystal panel 310 to be compared and the liquid crystal panel 310 to be inspected, the inspection of the terminal sections 19 can be appropriately performed. As described above, generation of erroneous detection of a defect due to a positional deviation of the main liquid crystal panel 310M can be appropriately suppressed. In fig. 15, the resolution adjustment unit 33 described in embodiment 1 is not shown.

According to the present embodiment described above, the main liquid crystal panel 310M is divided into a plurality of liquid crystal panels (inspection target regions) 310 in which a plurality of terminal portions (periodic inspection targets) 19 are arranged, and when the position adjustment indicator portions 40 are provided in each of the plurality of liquid crystal panels 310, the position adjustment portion 37 is provided for taking an image of the position adjustment indicator portion 40 by the camera 321 before the plurality of terminal portions 19 arranged in the liquid crystal panels 310 are taken by the camera 321, and adjusting the position of the main liquid crystal panel 310M based on the image of the position adjustment indicator portion 40. When inspecting the main liquid crystal panel 310M divided into a plurality of liquid crystal panels 310 in which a plurality of terminal portions 19 are arranged, the determination unit 331 may determine whether or not the terminal portions 19 are good by comparing an image of the terminal portions 19 arranged in another liquid crystal panel 310 with the reference image by setting the image of the terminal portions 19 arranged in a certain liquid crystal panel 310 as the reference image. At this time, since the period of the terminal portion 19 is increased due to the gap between the liquid crystal panel 310 to be compared and the liquid crystal panel 310 to be inspected, there is a possibility that a positional shift may occur in the main liquid crystal panel 310M when the terminal portion 19 of a certain liquid crystal panel 310 is photographed and when the terminal portion 19 of another liquid crystal panel 310 is photographed. In this way, the position adjustment unit 37 can read the position adjustment indicator unit 40 and adjust the position of the main liquid crystal panel 310M before checking the plurality of terminal units 19 arranged in the liquid crystal panel 310, and therefore generation of error detection of defects caused by the position of the main liquid crystal panel 310M can be appropriately suppressed.

(other embodiments)

The present invention is not limited to the embodiments described above and illustrated in the drawings, and for example, the following embodiments are also included in the technical scope of the present invention.

(1) In the above embodiments, the case where the inspection target substrate is the main liquid crystal panel is described, but the liquid crystal panel into which the main liquid crystal panel is divided may be the inspection target. The main array substrate and the main CF substrate before the main liquid crystal panel is bonded may be used as the inspection target substrates.

(2) In the above embodiments, the configuration in which one camera is attached to the camera moving unit is shown, but a configuration in which a plurality of cameras are attached to the camera moving unit may be adopted. In particular, as described in embodiment 2 in the configuration in which the cameras are moved in the Z-axis direction, since the range of the plurality of cameras changes with the movement in the Z-axis direction, it is preferable to rationalize the range of each camera by adjusting the distance between the cameras by relatively displacing the plurality of cameras in the Y-axis direction.

(3) In the above-described embodiment, the case where two lenses constituting the imaging member provided in the camera are provided is described, but the specific number, type, arrangement (order of arrangement), and the like of the lenses may be changed. In particular, in the configuration in which the lens is moved relative to the light receiving element as in embodiment 1, the moving direction of the lens may be in the direction other than the Z-axis direction by the arrangement of the lens.

(4) As a modification of embodiment 2 described above, the camera moving unit may be fixed in the Z-axis direction, and the camera may be moved in the Z-axis direction with respect to the camera moving unit.

(5) As a modification of embodiment 2 described above, the camera moving unit (camera) may be fixed in the Z-axis direction, or the main liquid crystal panel may be moved in the Z-axis direction. Further, the camera moving unit (camera) and the main liquid crystal panel may be moved in the Z-axis direction.

(6) As a modification of embodiment 3 described above, the adjustment of the angular difference may be performed by sucking the main liquid crystal panel by the suction member and rotating the suction member together with the main liquid crystal panel.

(7) In the above-described embodiments, the case where the light of the inspection backlight device is irradiated from the back side (the side opposite to the camera) with respect to the main liquid crystal panel is shown, and for example, the presence or absence of a defect such as a foreign substance in a pixel can be inspected by irradiating the light of the inspection optical element from the front side (the side opposite to the camera) with respect to the main liquid crystal panel.

(8) In addition to the above embodiments, the specific configuration of the inspection apparatus and the like may be changed as appropriate.

(9) In the above embodiments, the inspection apparatus used in the manufacture of the liquid crystal panel is described as an example, and may be an inspection apparatus used in the manufacture of a display panel of a type other than the liquid crystal panel (for example, an organic EL display panel or the like).

Description of the symbols

10M, 110M, 210M, 310M.. a main liquid crystal panel (inspection object substrate); a terminal portion (periodic inspection object); 20. 220, 320. 21. 121, 221, 321.. camera (image pickup section); 22. 122, 222.. camera moving part (photographing moving part); a light receiving element; an imaging component; a lens 26A, 26b.. the lens; 31. 131, 331.. judging part; 32. 132, 332. A resolution adjustment section; an angle adjustment part; a position adjustment portion; a position adjustment indicator; a liquid crystal panel (inspection target region); PX.. pixels (periodic inspection object).