JP2006090990A - Apparatus, method and program for inspecting transparent electrode film substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for inspecting a transparent conductive film (TCO) substrate, which can quantitatively and precisely inspect a state of the TCO substrate used for a thin film solar cell, and which enables a deposition state and the like to be visually observed while disposing the substrate on an inspection line. <P>SOLUTION: The apparatus is equipped with a photographing device 2 which photographs a surface of the TCO substrate A disposed on the inspection line; a processing device 3 which processes an image acquired by the photographing device 2 and detects a defect existing on the TCO substrate A, thereby inspecting the TCO substrate A; and a monitor 4 which displays the image acquired by the photographing device 2. The photographing device 2 has a focal position changing mechanism for changing a focal position. The processing device 3 extracts a focus coincidence image which is the most coincident one in focus, from a plurality of images being acquired by the photographing device 2 and having different focal positions, and detects the defect by using the extracted focus coincidence image. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an apparatus for inspecting a transparent electrode film substrate, for example, a transparent electrode film substrate used for a solar cell.

Conventionally, as shown in FIG. 13, for example, a thin film solar cell has a transparent electrode film (TCO film), a semiconductor film (eg, p layer, i layer, n layer, etc.), and a back electrode on a transparent glass substrate. It is manufactured through a process of sequentially laminating films.
By the way, when there are pinholes or foreign matters having a certain size or more on the transparent electrode film substrate obtained by laminating the transparent electrode film on the transparent glass substrate, Even if the semiconductor film and the back electrode film are laminated in order to produce a thin film solar cell, the final thin film solar cell has a poor photoelectric conversion rate, resulting in a defective product that cannot obtain a predetermined power generation efficiency. .
Therefore, it is necessary to inspect the transparent electrode film substrate for defects before laminating the semiconductor film and the back electrode film on the transparent electrode film substrate.

Such inspection of defects such as pinholes generated on the transparent electrode film substrate and adhering foreign matters has been conventionally performed by visual observation, but has a problem such as lack of quantitativeness.
Therefore, an apparatus for automatically performing defect inspection has been developed and proposed.
As an apparatus for automatically performing such a defect inspection of a transparent electrode film substrate, for example, there is one disclosed in Japanese Patent Laid-Open No. 2000-353814 (Patent Document 1).
Patent Document 1 discloses a technique for optically evaluating the film thickness state of a transparent electrode film substrate by performing spectral analysis of a reflection spectrum of a white light source.
JP 2000-353814 A (paragraphs [0025] to [0031] and FIG. 1)

According to the invention disclosed in Patent Document 1 above, it is possible to automatically and quantitatively determine the presence of foreign substances and the like, but in order for a person to check the state of the substrate, it is arranged on the inspection line. The substrate that had been used had to be taken out once. For this reason, there is an inconvenience that the state of the substrate cannot be visually observed while the substrate is still arranged on the line.
Therefore, it is desired to develop an inspection apparatus that can visually check the state of the substrate even when the substrate is still placed on the line and can quantitatively evaluate the substrate.

Here, for example, as a method for inspecting the state of the substrate, an inspection method is known in which the state of the substrate is photographed by an imaging device or the like, and foreign images on the substrate are automatically detected by processing these images. ing.
According to such an inspection method based on image processing, a photographed image is displayed on a monitor or the like, whereby visual observation is possible, and quantitative evaluation can be automatically realized.
However, a transparent electrode film substrate used in a thin film solar cell is very difficult to focus because the substrate is transparent and pinholes and foreign materials are often transparent.
For this reason, when the conventional image processing is applied as it is, various problems arise such that a clear image cannot be obtained, and the substrate and the defect are integrated, so that the substrate and the defect cannot be distinguished. The inspection could not be performed with high accuracy.

  The present invention has been made to solve the above-described problems, and can be used to quantitatively and accurately inspect the state of the transparent electrode film substrate of the thin-film solar cell, and with the substrate still placed on the inspection line. It is an object of the present invention to provide a transparent electrode film substrate inspection apparatus, method and program for visually checking the film state.

In order to solve the above problems, the present invention employs the following means.
The present invention provides an imaging device for imaging the surface of a transparent electrode film substrate for a thin-film solar cell disposed on an inspection line, and an image acquired by the imaging device, thereby existing in the transparent electrode film substrate A processing device that detects a defect to be detected and inspects the transparent electrode substrate, and a display device that displays an image acquired by the imaging device. The imaging device includes a focus position changing mechanism that changes a focus position. And the processing device extracts a focus matching image that best matches the focus from a plurality of images with different focus positions acquired by the imaging device, and uses the extracted focus matching image to extract the defect. An inspection apparatus for a transparent electrode film substrate for detecting the above is provided.

According to the present invention, the photographing apparatus acquires a plurality of images with the focus position changed. The processing device processes a plurality of images acquired by the imaging device and detects defects. Then, for example, inspection such as pass / fail judgment of the transparent electrode film substrate is performed according to the total number of detected defects or the size of the detected defects.
In this case, since the processing apparatus detects a defect using a focus-matched image with the best focus at each measurement point, for example, an image with the largest contrast ratio, the defect is clearly defined on the substrate. This makes it possible to detect defects accurately.
Furthermore, since a display device that displays a focus matching screen or the like is provided, it is possible for a human to visually observe the state of the substrate while the substrate is still placed on the inspection line.

  In the transparent electrode film substrate inspection apparatus described above, the processing device is configured to perform the image processing according to a predetermined order until a pixel having a luminance equal to or higher than a predetermined value can be detected in the plurality of images acquired by the imaging device. Each pixel, and when a pixel having a luminance equal to or higher than the predetermined value is detected, the coordinates of the pixel are specified, and an image having the highest luminance at the specified pixel coordinates is selected from the plurality of images. It is preferable to extract the image from the inside and set the extracted image as the focus matching image.

According to the present invention, the processing device searches the images one by one in a predetermined order until a pixel having a luminance equal to or higher than the predetermined value is detected in the plurality of images acquired by changing the focus position. When the pixel is detected, the coordinates of the pixel are specified.
For example, the processing apparatus extracts one image from a plurality of images according to a predetermined order, and searches whether or not there is a pixel having a luminance equal to or higher than a predetermined value in the image. At this point, if a pixel having a luminance equal to or higher than a predetermined value can be detected, the coordinates of this pixel are specified. On the other hand, if such a pixel cannot be detected, the pixel is similarly searched for an image set in the next order.

In this way, when the coordinates of a pixel having a luminance equal to or higher than a predetermined value are specified, the processing device extracts an image having the highest luminance at the specified pixel coordinates from the plurality of images. Is determined as a focus-match image.
Thus, paying attention to the coordinates of the pixel having the luminance of the predetermined value or more detected first, and specifying the image having the highest luminance at the coordinates of this pixel as the focus matching image, It is possible to quickly select an image with the best focus.

In addition, for example, when a pixel having a luminance equal to or higher than a predetermined value cannot be detected as a result of searching all of the plurality of acquired images, it can be determined that there is no defect.
For example, when a plurality of pixels having a luminance equal to or higher than a predetermined value can be detected in one image, the coordinate having the highest luminance is specified.
For example, when an image is composed of a color image signal (RGB signal), two-dimensional arrangement of the color image signal (RGB signal) is performed by detecting a pixel having a luminance of a predetermined value or more. An image (original image) is generated, and edge detection processing by a spatial filter is performed on the original image to generate an edge detection processing image. Among the edge detection processing images, pixels having a differential value equal to or greater than a predetermined value are generated. It can be realized by detection.

  Further, the processing device first searches for an image acquired at an initial focus position where the focus position is estimated to be the best match, and then acquires an image acquired at a focus position close to the initial focus position. It is preferable to search in order.

  According to the present invention, the image acquired at the initial focus position that is estimated to be the closest to the focus position is searched first, and then the image acquired at the focus position close to the initial focus position. The pixels having a luminance equal to or higher than a predetermined value are detected in order. As described above, since the search is performed for pixels having a luminance equal to or higher than a predetermined value in order from an image that is estimated to have the best focus position, for example, an image that is estimated to have the highest contrast ratio. This makes it possible to identify an accurate pixel at an early stage, and shorten the processing time.

  Further, the processing device generates a two-dimensional image by two-dimensionally arranging the focus-matched images, performing an edge detection process using a spatial filter on the two-dimensional image, and generating an edge detection processing image. A brightness histogram is created based on the brightness of the edge detection image, a threshold value for binarizing the edge detection image is specified based on the brightness histogram, and the edge detection image is used using the specified threshold value It is preferable to generate a binarized image from the image and detect the defect in a determination image obtained by processing the binarized image.

According to the present invention, a two-dimensional image is generated by two-dimensionally arranging focus matching images, and an edge detection processing image is generated by subjecting the two-dimensional image to edge detection processing using a spatial filter. Then, the edge detection image is binarized based on a predetermined threshold value to generate a binarized image, and a defect is detected in the determination image obtained by performing predetermined processing on the binarized image.
In this case, since the threshold value used when obtaining the binarized image from the edge detection image is determined based on the luminance histogram obtained from the edge detection image, binarization is performed individually according to the image appearance. Is possible. Thereby, since binarization can be performed appropriately, a defect can be detected accurately.

  The present invention detects defects in the transparent electrode film substrate by processing an image of the surface of the transparent electrode film substrate for a thin film solar cell disposed on an inspection line, and inspects the transparent electrode substrate. A method of inspecting a transparent electrode substrate to perform, a process of acquiring a plurality of images having different focus positions, and a focus matching image in which the focus is most closely matched from among the plurality of acquired images having different focus positions A transparent electrode substrate inspection method comprising: a process; a process of detecting the defect using the extracted focus-matched image; and a process of displaying the focus-matched image.

  The present invention provides an imaging device for imaging the surface of a transparent electrode film substrate for a thin-film solar cell disposed on an inspection line, and an image acquired by the imaging device, thereby existing in the transparent electrode film substrate Used for a transparent electrode film substrate inspection apparatus comprising: a processing apparatus that detects defects to be detected and inspects the transparent electrode substrate; and a display apparatus that displays an image acquired by the imaging apparatus, and is executed by the processing apparatus. A transparent electrode film substrate inspection program, the step of extracting a focus-matched image in which the focus is best matched from a plurality of images having different focus positions acquired by the imaging device; and the extracted A program for inspecting a transparent electrode film substrate comprising a step of detecting the defect using a focus matching image.

  According to the transparent electrode film substrate inspection apparatus of the present invention, the state of the substrate can be inspected quantitatively and accurately, and the state of the substrate can be confirmed while the substrate is still placed on the inspection line. Can do.

  Hereinafter, defect inspection of a transparent electrode film substrate according to an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram showing a configuration of a transparent electrode film substrate inspection apparatus according to an embodiment of the present invention.
As shown in FIG. 1, in the transparent electrode film substrate inspection apparatus 1 according to the present embodiment, the transport conveyor 5 arranged in the inspection line is a transparent electrode film substrate (hereinafter, referred to as a thin film solar cell) to be inspected. "TCO substrate")) A is transported in the transport direction Y while being kept in a horizontal state. A photoelectric switch, a rotary encoder, etc. (not shown) are arranged on the conveyor 5. Output signals from these photoelectric switches and rotary encoders are input to the line control device 6. The line control device 6 controls the conveyor 5 based on these signals, and moves and stops the TCO substrate A to a predetermined position.

An imaging device 2 is disposed above the conveyor 5. The imaging device 2 includes, for example, six microscope devices 21. These microscope devices 21 are arranged in a row so as to be orthogonal to the transport direction Y of the TCO substrate A.
As shown in FIG. 2, the microscope apparatus 21 has a configuration in which a microscope 22, a linear gauge 23, and a Z-axis stage (focus position changing mechanism) 24 are integrated.
The microscope 22 images the surface of the TCO substrate A arranged on the inspection line. The linear gauge 23 detects the position of the TCO substrate A. The Z-axis stage 24 moves in a plane direction perpendicular to the surface of the TCO substrate A (hereinafter referred to as “Z-axis direction”), thereby moving the position of the integrated microscope 22 in the Z-axis direction. Move. Thereby, since the distance between the microscope 22 and the surface of the TCO substrate A changes, the focus position of the microscope 22 can be changed. Note that the Z-axis stage 24 is connected to the processing apparatus 3 shown in FIG. 1, and movement control in the Z-axis direction is performed by the processing apparatus 3. The microscope apparatus 21 is provided with an illuminator (not shown). The illuminator is composed of a fluorescent lamp, for example, and the brightness is adjusted by a dimmer (not shown).

As shown in FIG. 3, the imaging apparatus 2 including the six microscope apparatuses 21 captures the surface of the TCO substrate A at a total of 42 measurement points including 6 points × 7 rows.
The image data acquired by the imaging device 2 is output to the processing device 3 as an NTSC signal, for example, as shown in FIG. This NTSC signal includes a red component image signal R, a green component image signal G, and a blue component image signal B.
The processing device 3 processes the NTSC signal that is the image data of the surface of the TCO substrate acquired from the imaging device 2, thereby detecting defects present on the TCO substrate A and inspecting the TCO substrate A. The monitor (display device) 4 displays an image based on a predetermined NTSC signal output from the processing device 3.

Next, the operation of the transparent electrode film substrate inspection apparatus according to the present embodiment having the above-described configuration will be described.
In the present embodiment, the TCO substrate A to be inspected has a length of 1400 mm and a width of 1100 mm as shown in FIG.
First, the line control device 6 controls the transport conveyor 5 to move the TCO substrate in the transport direction Y. When the measurement points in the first row of the TCO substrate A (coordinates 1-1 to 1-6 in FIG. 3) are located directly below the microscopes 22 included in the respective microscope devices 21, the conveyor 5 is stopped. The inspection start signal S is transmitted to the processing device 3.

When the processing device 3 receives the inspection start signal S, the processing device 3 inspects the TCO substrate for the measurement points in the first column (coordinates 1-1 to 1-6 in FIG. 3). This inspection is realized by the CPU included in the processing device 3 reading out the program for inspecting the transparent electrode film substrate stored in the memory in the processing device 3 or a computer-readable medium to the RAM and executing it. Is.
Hereinafter, the inspection process of the transparent electrode film substrate executed by the processing apparatus 3 will be described with reference to FIG. The following inspection processing is performed for each measurement point.

First, the processing device 3 performs a standby position movement process (step SA1 in FIG. 4). For example, as shown in FIG. 5, by moving the Z-axis stage 24 (see FIG. 2) included in each microscope device 21 (see FIG. 1) in the Z-axis direction, the tip of the linear gauge 23 and the TCO The distance from the substrate A is 3 mm to 5 mm.
Subsequently, the processing apparatus 3 performs a substrate position detection process (step SA2 in FIG. 4). In this process, each Z-axis stage 24 is lowered (in a direction approaching the TCO substrate A), so that the tip of the linear gauge 23 is placed on the TCO substrate A as shown in FIG. The presence / absence of the plate can be determined by checking the counter of the linear gauge 23, for example.

Subsequently, the processing device 3 performs an acquisition start position movement process (step SA3 in FIG. 4). In this process, as shown in FIG. 7, the microscope 22 is moved to the image capture start position by raising each Z-axis stage 24 (in a direction away from the TCO substrate A).
For example, the image capture start position is a position obtained by adding a half distance of the image capture section to the initial focus position where the focus position is estimated to be the best match. This can be expressed by the following equation (1).
Capture start position = initial focus position + (image capture section / 2) (1)
Here, the image capture section corresponds to a distance to move the focus position when photographing the surface of the TCO substrate A, and represents a distance from the focus position closest to the TCO substrate to the focus position farthest from the TCO substrate. Say. In the present embodiment, for example, the image capture section is set to 200 μm.

Subsequently, the processing device 3 performs an image capture process (step SA4 in FIG. 4). In this process, the surface of the TCO substrate A is imaged multiple times by the microscope 22 while gradually changing the focus position of each microscope 22.
For example, in the present embodiment, the focus position is determined at intervals of 20 μm in the vertical direction over the image capturing section with the initial focus position as the center, and the surface of the TCO substrate A at each focus position is photographed.
Shooting starts from the capture start position, which is the focus position farthest from the TCO substrate A, and captures images at the respective focus positions in order of gradually approaching the TCO substrate A.
In the present embodiment, since the image capture section is set to 200 μm, a total of 11 captures are performed, and in the first capture, an image whose focus position is the image capture start position is captured, and the sixth capture. In this shooting, an image with the focus position as the initial focus position is captured.
The image captured by the microscope 22 is output to the processing device 3 as an NTSC signal.
Accordingly, the processing device 3 can obtain a plurality of images (hereinafter referred to as “captured images”) acquired at different focus positions.

Next, the processing device 3 performs defect detection processing (step SA5 in FIG. 4). In this processing, for example, the processing procedure as shown in FIG. 8 is performed.
First, attention point identification processing is performed (step SB1 in FIG. 8).
In this process, first, in a plurality of images (11 images in this embodiment) acquired at different focus positions in the above-described image capturing process (step SA4 in FIG. 4), the luminance is equal to or higher than a predetermined value. Until a pixel is detected, the images are searched one by one in a predetermined order. When the pixel is detected, the pixel is identified as a point of interest, and the coordinates (X, Y) of this point of interest are determined. Identify.

  Specifically, first, in the above-described image capturing process (step SA4 in FIG. 4), among the 11 images captured while changing the focus position, the image at the initial focus position, that is, the sixth capture. The embedded image is extracted (step SC1 in FIG. 9). Next, it is determined whether or not there is a pixel having a luminance equal to or higher than a predetermined value in the captured image extracted in step SC1 (step SC2).

As a result, when there is a pixel having a luminance equal to or higher than a predetermined value (“YES” in step SC2), it is determined whether or not there are a plurality of such pixels in the image (step SC3). As a result, when there is only one pixel having a luminance equal to or higher than a predetermined value (“NO” in step SC3), the pixel is specified as a point of interest (step SC4), and the process is terminated.
On the other hand, when there are a plurality of pixels whose luminance is a predetermined value or more, for example, as shown in FIG. 10, when a plurality (7 points) are detected in one image (“YES” in step SC3). The point having the highest luminance (for example, point P in the figure) is identified as the point of interest (step SC5), and the point-of-interest identifying process is terminated.

On the other hand, if there is no pixel having a luminance equal to or higher than a predetermined value in the image acquired at the initial focus position in step SC2 ("NO" in step SC2 in FIG. 9), the pixel search is performed. Of the 10 images that are not displayed, an image acquired at the focus position closest to the initial focus position, for example, the fifth captured image is extracted (step SC6 in FIG. 9). Then, it is determined whether or not there is a pixel having a luminance equal to or higher than a predetermined value in the image (step SC2). In this way, the processing device 3 repeats the processes of step SC6 and step SC2 until a pixel having a luminance equal to or higher than a predetermined value is detected.
It should be noted that in all the images, when there are no pixels with a luminance greater than or equal to a predetermined value, that is, when there are no pixels with a luminance greater than or equal to the predetermined value in 11 images, this It determines with there being no defect in a measurement point, and complete | finishes the said process.

  For example, when an image is composed of a color image signal (RGB signal), the detection of a pixel having a luminance equal to or higher than the predetermined value described above is performed by two-dimensionally arranging the color image signal (RGB signal). A two-dimensional image (original image) is generated, and edge detection processing using a spatial filter is performed on the original image to generate an edge detection processing image. The differential value of the edge detection processing image is equal to or greater than a predetermined value. This can be realized by detecting pixels.

When the attention point is specified in the attention point specifying process (step SB1 in FIG. 8) described above, the processing device 3 subsequently performs the focus matching image specifying process (step SB2 in FIG. 8).
In this process, first, the brightness of the coordinate (X, Y) of the point of interest P in all 11 images captured in the image capture process of FIG. 4 is detected, and the brightness at this coordinate (X, Y) is detected. The highest image is identified as the focus matching image.
For example, when the luminance of the coordinates (X, Y) of the point of interest P in each image shows a value as shown in FIG. 11, the sixth captured image with the highest luminance is specified as the focus matching image. .

Next, the processing device 3 performs defect identification processing (step SB3 in FIG. 8). In this processing, the focus matching images specified in the above-described focus matching image specifying processing (step SB2 in FIG. 8) are two-dimensionally arranged to generate a two-dimensional image, and edge detection processing using a spatial filter is performed on the two-dimensional image. To generate an edge detection processing image.
Subsequently, a luminance histogram is created based on the luminance of the edge detection image, and a binarization threshold value for binarizing the edge detection image is specified based on the luminance histogram.
Here, FIG. 12 shows an example of a luminance histogram. As shown in FIG. 12, the luminance histogram is a graph of the number of pixels at each luminance. In this luminance histogram, a boundary point where the number of pixels is equal to or less than a preset specified value is specified as a binarization threshold.
Then, a binarized image is generated from the edge detection image using the binarization threshold value, and a determination image is generated by performing expansion / filling / shrinkage processing on the binarized image. Then, in this determination image, a portion where the area is equal to or larger than a predetermined value and the average luminance in this area is equal to or larger than the predetermined value is specified as a defect.
And the sum total of the location specified as a defect is preserve | saved as the number of the defects in the said measurement point.
When the above process ends, the defect detection process in step SA5 in FIG. 4 ends.

The processing device 3 performs the processing from step SA1 to step SA5 in FIG. 4 on the measurement points in the first column (coordinates 1-1 to 1-6) shown in FIG. When the number of defects is stored, it is subsequently determined whether or not the above-described processing has been completed for all measurement points, that is, the 42 measurement points shown in FIG. 3 (step SA6 in FIG. 4).
As a result, since only the measurement points in the first row have been inspected (“NO” in step SA6), the processing device 3 outputs a substrate transfer command to the line control device 6 (step SA7). .
As a result, the line control device 6 transports the TCO substrate A in the transport direction Y, and stops the TCO substrate A when the next measurement point row, that is, each measurement point in the second row is located under the microscope. .
Thereby, the processing device 3 performs the processing of steps SA1 to SA5 shown in FIG. 4 at each of the measurement points (coordinates 2-1 to 2-6) in the second row.

In this way, when the processing from step SA1 to step SA7 is repeatedly performed and defects are specified for all measurement points (“YES” in step SA6), the processing apparatus 3 causes the TCO board A to The ID is fetched (step SA8), and the pass / fail judgment of this TCO substrate A is performed (step SA9).
The pass / fail determination is made, for example, based on whether or not there are five or more measurement points at which 20 or more defects are specified in the defect detection process of step SA5.
As a result, if there are five or more measurement points where 20 or more defects are specified, the substrate is determined as an NG substrate, whereas if it is less than 5, the substrate is determined as a normal substrate. Then, the process ends.

  Note that, through the entire processing described above, the processing device 3 appropriately outputs an image signal at the measurement point currently being processed to the display device 4 to display a captured image or the like. As a result, the display device displays a focus match image, a determination image obtained by processing the focus match image, and the like. As a result, an operator or the like can visually check the state of the substrate while the substrate is installed on the inspection line.

As described above, according to the inspection apparatus for a transparent electrode film substrate according to the present embodiment, the processing device 3 detects a defect by using a focus matching image in which the focus is best matched at each measurement point. It becomes possible to clarify the defect with respect to the substrate, and the defect can be accurately detected.
Furthermore, since a display device for displaying a focus matching screen or the like is provided, the state of the substrate can be visually observed by the person while the substrate is placed on the inspection line.

In the above-described image capturing process in the present embodiment, one image is acquired at each focus position. However, the number of images acquired at each focus position can be changed as appropriate. For example, 20 images can be captured at each focus position, and one image obtained by smoothing the 20 images can be handled as an image at the focus position in subsequent processing.
Further, in the defect identification process (step SB3 in FIG. 8) of the defect detection process (step SA5 in FIG. 4), a binarized image is generated from the edge detection image, and an expansion / hole filling / contraction process is performed on the binarized image. In this determination image, the area where the area is equal to or greater than the predetermined value and the average luminance in the area is equal to or greater than the predetermined value is identified as the defect. The specific method is not limited to this method.
For example, the defect may be specified by using a pattern matching technique, a technique using spatial differentiation, or the like. Even in such a case, according to the present embodiment, since the focus matching image having the highest contrast ratio is used, it is easy to distinguish between the transparent substrate and the defect, and the defect can be specified with high accuracy. Become.

As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the specific structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.
For example, the substrate position is detected by the linear gauge 23, but the substrate position may be detected by using a non-contact sensor.

It is the figure which showed the structure of the inspection apparatus of the transparent electrode film board | substrate which concerns on one Embodiment of this invention. It is a figure which shows the structure of the microscope apparatus of FIG. It is a figure which shows the measuring point set on the TCO board | substrate. It is a flowchart which shows the procedure of the inspection process of the transparent electrode substrate performed with a processing apparatus. FIG. 5 is a diagram illustrating a positional relationship between a microscope and a TCO substrate in the standby position movement process of FIG. 4. FIG. 5 is a diagram showing a positional relationship between a microscope and a TCO substrate in the substrate position detection process of FIG. 4. FIG. 5 is a diagram illustrating a positional relationship between a microscope and a TCO substrate in the capture start position movement process of FIG. 4. It is a flowchart which shows the process sequence of the defect detection process of FIG. It is a flowchart which shows the process sequence of the attention point specific process of FIG. It is explanatory drawing for demonstrating an attention point. It is the figure which showed the brightness | luminance of the coordinate of the attention point in each captured image. It is the figure which showed an example of the brightness | luminance histogram. It is a figure which shows an example of the manufacturing process of a thin film solar cell.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transparent electrode film board | substrate inspection apparatus 2 Imaging device 3 Processing apparatus 4 Monitor 21 Microscope apparatus 22 Microscope 23 Linear gauge 24 Z-axis stage

Claims (6)

An imaging device that images the surface of a transparent electrode film substrate for a thin film solar cell disposed on an inspection line, and a defect present in the transparent electrode film substrate is detected by processing an image acquired by the imaging device And a processing device for inspecting the transparent electrode substrate, and a display device for displaying an image acquired by the imaging device,
The photographing apparatus includes a focus position changing mechanism that changes a focus position,
The processing device extracts a focus-match image having the best focus from a plurality of images having different focus positions acquired by the photographing device, and detects the defect using the extracted focus-match image. Inspection device for transparent electrode film substrate. The processor is
In the plurality of images acquired by the photographing device, search for the images one by one according to a predetermined order until a pixel having a luminance equal to or higher than a predetermined value can be detected,
When a pixel having a luminance equal to or higher than the predetermined value is detected, the coordinates of the pixel are specified,
An image having the highest luminance at the coordinates of the identified pixel is extracted from the plurality of images,
The inspection apparatus for a transparent electrode film substrate according to claim 1, wherein the extracted image is the focused image.   The processing device first searches for an image acquired at an initial focus position where the focus position is estimated to be the best match, and then sequentially from an image acquired at a focus position close to the initial focus position. The inspection apparatus for a transparent electrode film substrate according to claim 2 for searching. The processor is
A two-dimensional array of the focus-match images to generate a two-dimensional image;
The two-dimensional image is subjected to edge detection processing using a spatial filter to generate an edge detection processing image,
Create a brightness histogram based on the brightness of the edge detection image,
Based on the luminance histogram, a threshold value for binarizing the edge detection image is specified,
A binarized image is generated from the edge detection image using the identified threshold value,
The inspection apparatus for a transparent electrode film substrate according to any one of claims 1 to 3, wherein the defect is detected in a determination image obtained by processing the binarized image. A transparent electrode substrate for detecting defects existing in the transparent electrode film substrate by processing an image of the surface of the transparent electrode film substrate for a thin film solar cell disposed on the inspection line, and inspecting the transparent electrode substrate The inspection method of
The process of acquiring multiple images with different focus positions;
A process of extracting a focus matching image in which the focus is the best from a plurality of acquired images having different focus positions;
Using the extracted focus-matched image to detect the defect;
A method of inspecting the transparent electrode substrate, comprising: displaying the focus-matched image. An imaging device that images the surface of a transparent electrode film substrate for a thin film solar cell disposed on an inspection line, and a defect present in the transparent electrode film substrate is detected by processing an image acquired by the imaging device The transparent electrode is used in an inspection apparatus for a transparent electrode film substrate that includes a processing apparatus that inspects the transparent electrode substrate and a display apparatus that displays an image acquired by the imaging apparatus, and is executed by the processing apparatus. A program for inspecting a membrane substrate,
Extracting a focus-matched image with the best focus from a plurality of images with different focus positions acquired by the photographing device;
A program for inspecting a transparent electrode film substrate, comprising: detecting the defect using the extracted focus matching image.

Images