JP5187851B2 - Inspection apparatus and inspection method - Google Patents

Description

  The present invention relates to an inspection apparatus and an inspection method, and more particularly to an inspection apparatus and an inspection method for inspecting the application state of transparent fine particles such as silicon in a product such as a syringe.

2. Description of the Related Art Conventionally, a product such as a syringe is inspected based on a camera for photographing a product, a binarization circuit for binarizing an image obtained by the camera, and an image binarized by the binarization circuit. There is known an inspection apparatus provided with a determination means for determining the quality of the product.

The inspection apparatus counts the number of black or white pixels in the binarized image, and determines that the product is defective when the total number of pixels is not within a predetermined range. If the product has dust or scratches, the number of black pixels increases, and the number of white pixels decreases accordingly, so that the quality of the product can be determined.

Japanese Patent Laid-Open No. 11-183401

By the way, in recent years, syringes are increasingly used as prefilled syringes. The prefilled syringe is sealed by filling a medicine in the syringe and inserting a pusher to which a gasket is connected. In the prefilled syringe, silicon as a lubricant is applied to the inner wall surface of the syringe body so that the medicine can be administered by operating the pusher smoothly.

Since such syringes and silicon are both transparent and a small amount of silicon can be applied, it is very difficult to visually inspect whether or not silicon is applied to the syringe. Currently, manufacturers that manufacture syringes detect the presence or absence of silicon application through the tip of a nozzle that applies silicon, but sufficient inspection accuracy has not been obtained. In addition, when applying silicon, particularly when the viscosity of silicon is high, the coating amount may vary.

On the other hand, according to the conventional inspection apparatus, although it is possible to inspect the syringe for dust or scratches, silicon cannot appear in the binarized image, so whether or not silicon is applied to the syringe. It was difficult to inspect the application state of silicon, such as whether or not the application amount was appropriate.

Therefore, the present invention has been made in view of the above circumstances, and its object is to quickly and easily inspect the application state of transparent fine particles such as silicon in a product such as a syringe with high accuracy. It is an object of the present invention to provide an inspection apparatus and an inspection method that can perform inspection. Other objects of the present invention will become apparent from the following description.

The inspection apparatus of the present invention is an inspection apparatus for inspecting the application state of transparent fine particles in a product, wherein an illumination unit that illuminates transmitted light, a light transmitting unit, and a light shielding unit are alternately perforated, and the product And a slit plate that forms bright and dark stripes in which bright parts and dark parts are alternately repeated with respect to the product, and receives the transmitted light transmitted through the product, An image processing unit that captures a product, an image processing unit that performs image processing on a captured image captured by the image capturing unit to form a multi-tone gray image, and a halftone image in an inspection area in the gray image. Based on the number of the change points, a detection unit that detects a boundary between the fine particles based on a gradation difference between each fine particle of the transparent fine particle appearing at the bright portion or the dark portion, and the number of the change points And a determination unit for determining the application state of.

  In a preferred example of the inspection apparatus of the present invention, the detection unit detects the change point along a scanning direction parallel to the light and dark stripes.

  In a further preferred example of the inspection apparatus of the present invention, the detection unit detects the change points at both side edges along the scanning direction of the fine particles, thereby detecting two change points for each fine particle. Has been made.

  In a further preferred example of the inspection apparatus according to the present invention, the inspection region includes a plurality of inspection blocks, the detection unit detects the change point for each inspection block, and the determination unit detects the detected points. The application state of the transparent fine particle body is determined by comparing the total value obtained by adding the number of change points with a predetermined determination criterion.

  In a further preferred example of the inspection apparatus according to the present invention, the product is a syringe, and the application state of silicon on the inner wall surface of the syringe is inspected.

  Further, the inspection method of the present invention is an inspection method for inspecting the application state of the transparent fine particles in the product, and illuminates the transmitted light so that bright and dark stripes in which the bright part and the dark part are alternately repeated on the product. A step of forming, a step of receiving the transmitted light that has passed through the product and photographing the product, a step of performing image processing on the photographed photographed image to form a multi-tone image, Detecting the boundary of the fine particle as a change point of light and dark according to a gradation difference between each fine particle of the transparent fine particle body appearing in a halftone and the bright part or the dark part in the inspection region in the grayscale image; And a step of determining a coating state of the transparent fine particle body based on the number of change points.

  According to the present invention, as described above, the illuminating unit that illuminates the transmitted light, the translucent unit, and the light-shielding unit are alternately perforated and disposed between the product and the illuminating unit. On the other hand, a slit plate that forms bright and dark stripes in which a bright part and a dark part are alternately repeated, a photographing part that receives the transmitted light that has passed through the product, and photographs the product, and is photographed by the photographing part An image processing unit that performs image processing on the captured image to form a multi-gradation gray image, and each fine particle of the transparent fine particle that appears in halftone in the inspection region in the gray image and the bright portion or Inspection comprising: a detection unit that detects a boundary between the fine particles as a change point of light and darkness based on a gradation difference from the dark part; and a determination unit that determines a coating state of the transparent fine particle body based on the number of the change points Because the device is configured, transparent fine particles such as silicon in products such as syringes The coating state, quickly and easily, yet can be accurately inspected.

It is a whole lineblock diagram showing the inspection device concerning an embodiment. It is explanatory drawing which shows the grayscale image which concerns on embodiment. It is a figure which shows the example of the grayscale image when not using a slit board. It is a figure which shows the example of the grayscale image at the time of using a slit board. It is explanatory drawing which shows the test | inspection procedure which concerns on embodiment. It is explanatory drawing which shows the test | inspection procedure which concerns on embodiment. It is a schematic plan view which shows the inspection system which concerns on embodiment. It is a figure which shows the grayscale image which concerns on an Example (sample A). It is a figure which shows the test | inspection image which concerns on an Example (sample A). It is a figure which shows the grayscale image which concerns on an Example (sample B). It is a figure which shows the test | inspection image which concerns on an Example (sample B). It is a figure which shows the test | inspection area | region and test | inspection block of an Example.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is an overall configuration diagram illustrating an inspection apparatus 10 according to an embodiment.

The inspection apparatus 10 inspects the application state of silicon in a syringe as a product. As shown in FIG. 1, the illumination unit 20 is arranged on one side and the imaging unit 30 is arranged on the other side with the syringe 11 interposed therebetween. It is configured.
The syringe 11 is made of transparent plastic or glass having a volume of about 5 to 10 milliliters, and includes a flange portion 13 and a diameter-reduced portion 14 that gradually decreases in diameter toward the distal end portion 15 above and below the cylindrical body portion 12. Each has a known structure coupled with each other. Silicon as a lubricant is applied to the inner wall surface 16 of the body 12. The syringe 11 is appropriately held in a vertical state through a holding means (not shown) with the distal end portion 15 facing downward.

Silicon is based on prescribed standards (for example, Drug Machine No. 327 “Standards for Silicon Oil Used as Lubricant for Injection Needles and Syringes, etc. (December 20, 1995 Ministry of Health and Welfare Pharmaceutical Affairs Department Medical Device Development Division Manager Notice)”) Although satisfy | filling, an oil silicone or an emulsion silicone is used selecting it suitably according to the compatibility with the material of the syringe 11, the chemical | medical agent with which it fills, etc.

The illumination unit 20 illuminates the transmitted light 21 substantially horizontally as shown in FIG. The illumination unit 20 has a thin box shape in which a large number of LED light sources (not shown) are densely arranged in a vertical and horizontal grid pattern and is covered with an acrylic plate 23, and is at least one more than the syringe body unit 12. It has a large vertical projection surface. The acrylic plate 23 functions to appropriately diffuse the transmitted light 21 from the LED light source. The LED is a preferable light source because it has a long lifetime and can easily maintain brightness uniformity, and the illumination unit 20 can be configured compactly.

As shown in FIG. 1, a slit plate 25 in which a plurality of light transmitting portions 26 and light shielding portions 27 are alternately drilled is provided between the syringe 11 and the illumination portion 20. It is arranged in parallel with the surface. Thereby, the slit board 25 forms the predetermined light and dark stripe 40 in which the bright part 41 and the dark part 42 are repeated with respect to the syringe 11 along the axial direction of the syringe 11 (refer FIG. 2).

In this embodiment, the pitch of the slit plate 25 is formed with the dimensions of W ₁ = 2 (mm) and W ₂ = 2 (mm) (FIG. 1). The preferable range of W ₁ and W ₂ is as follows: When the diameter of the syringe body 12 is approximately 5 to 20 (mm), it is 1 to 5 (mm), and more preferably, W ₁ = W ₂ .
In addition, the thickness D of the slit plate 25 can be appropriately set in consideration of the dimensions of W ₁ and W ₂ and the distance between the illumination unit 20 and the slit plate 25. In this embodiment, it is formed with a dimension of D = 2 (mm).

The slit plate 25 may be disposed at an appropriate position in accordance with a space limitation due to the transport mode of the syringe 11. The slit plate 25 can be fixed to the surface of the acrylic plate 23 of the illumination unit 20. Further, if the illumination unit 20 and the slit plate 25 are configured to be horizontally movable, they may be adjusted to the optimal position each time depending on the type of syringe 11 to be inspected (diameter of the body unit 12) and the like. Becomes easy.

As illustrated in FIG. 1, the imaging unit 30 receives the transmitted light 21 a illuminated from the illumination unit 20 and transmitted through the syringe 11 from the opposite side, and images the syringe 11. In this embodiment, the photographing unit 30 is composed of a double speed random camera (four times speed), and can capture an image by photographing a substantially entire projection image of the syringe body part 12 in about 16 (milliseconds).
The photographing unit 30 is optimally disposed at a position where the transmitted light 21a can be received from the front, but the number of the photographing unit 30 is not limited to one, and a plurality of units may be provided.

  As shown in FIG. 1, a predetermined inspection unit 35 is connected to the imaging unit 30. The inspection unit 35 mainly includes an image processing unit 36, a detection unit 37, and a determination unit 38. The image processing unit 36 performs image processing on the captured image captured by the imaging unit 30 to form a grayscale image, and the detection unit 37 performs a predetermined detection process using the grayscale image. And based on the result of a detection process, the determination part 38 determines the application | coating state of the silicon | silicone in the syringe 11. FIG.

  Although not shown, the inspection unit 35 includes necessary storage and hardware such as a storage unit such as a memory, an arithmetic processing unit such as a CPU, a predetermined program, an interface, and a power supply port. Display means such as a monitor and a display, input means such as a keypad, a touch panel, and a joystick and other peripheral devices are appropriately connected.

A specific inspection procedure using the inspection apparatus 10 configured as described above will be described. First, the photographing unit 30 photographs the syringe 11 set in a predetermined state, and obtains a photographed image.

The captured image is converted into digital data, and the image processing unit 36 performs predetermined image processing for forming a grayscale image. A known technique is used as the image processing method itself. That is, in the image data sampled into a set of a large number of pixels, each pixel is quantized to a gradation level of 256 gradations, for example, 0 to 255, and a grayscale gradation image (multi-valued expression) expressed in multiple gradations. Image).

At this time, in the syringe 11 in the grayscale image, as shown in FIG. 2, the above-described illumination unit 20 and slit plate 25 cause a bright portion 41 that forms white near the highlight and a dark portion 42 that forms black near the shadow. The light and dark stripes 40 that are alternately repeated are formed, but each silicon fine particle 45 appears as a gray shade of gray.

FIG. 3 is an example of a grayscale image formed without using a slit plate for a syringe 11 coated with silicon, while FIG. 4 shows an example using the slit plate for the same syringe 11 as described above. An example of the formed grayscale image is shown. As is clear from these figures, transparent silicon, which originally has transmitted light 21a around the particle and cannot appear in the grayscale image, appears clearly with the predetermined shadow by passing through a certain slit plate. It can be done.

This is because the silicon fine particles 45 located in the bright part 41 are darkened by the influence of the light-shielding parts 27 on both sides due to the action of the light-transmitting part 26 and the light-shielding part 27 of the slit plate 25. It is considered that the silicon fine particles 45 located in the dark part 42 appear to appear white due to the light-transmitting parts 26 on both sides (see FIG. 2).

It is preferable to perform position correction after the gray image is formed. Since the contour portion of the body portion 12 and the flange portion 13 of the syringe 11 are difficult to transmit the transmitted light 21a and appear in a black contour line, the position of the syringe 11 can be corrected based on this. In particular, when the syringe 11 in the middle of conveyance is inspected by intermittent shooting, the position of the syringe 11 may be different for each image, but the following detection process can be more easily performed by such position correction.

As shown in FIG. 5, the detection process by the detection unit 37 is performed by providing a certain inspection region 50 in the grayscale image. The inspection region 50 may be provided in any manner, and may be provided on the whole or a part of the syringe 11. Further, the inspection area 50 can be divided into a plurality of inspection blocks. By dividing into a plurality of inspection blocks and integrating them, the inspection accuracy can be further improved.
In the syringe 11, since it is particularly important to check the silicon application state on the distal end 15 side of the body portion 12, it is preferable to provide the inspection region 50 at least in the vicinity thereof.

In the detection process, in the inspection area 50, the boundary between the fine particles 45 is changed by the gradation difference between the fine particles 45 of silicon appearing in the halftone and the background (the bright portion 41 or the dark portion 42). This is done by detecting as a point.
More specifically, the case of the syringe 11 to which silicon is applied will be described with reference to FIG. 5. A rectangular inspection region 50 is set at an appropriate position in the grayscale image, and predetermined edge detection is performed as preprocessing. Thus, the boundary (edge) of each fine particle 45 is detected. In edge detection, the light / dark gradation of each pixel is sequentially extracted in the inspection area 50, the amount of change in light / dark gradation between pixels is calculated, and the amount of change is compared with a predetermined threshold value. If the amount of change is equal to or greater than a predetermined threshold, it is detected as an edge. For example, if the set threshold value is “30”, a point where the light / dark gradation decreases by 30 or more is detected as an edge from “bright to dark”, and conversely, a place where the light / dark gradation increases by 30 or more. Detect as an edge from “dark to light”. In calculating the amount of change, a technique such as difference processing is appropriately used.
This edge detection is performed along the scanning direction A parallel to the light and dark stripes 40. However, since the silicon fine particles 45 appear as shades of the gray of the halftone, the edge detection is performed with the bright portion 41 or the dark portion 42. Due to the difference in gradation, it is possible to detect edges of these boundaries easily and accurately. By performing edge detection along the scanning direction A, it becomes easy to detect only the boundaries of the respective fine particles 45 without requiring complicated processing.

Based on the edge detection, a change point between light and dark is detected. In FIG. 5, 51 is an edge checker that searches for a light-dark change point along the scanning direction A. In this embodiment, both side edges along the scanning direction A at the boundary where the edge of each fine particle 45 is detected are set to be detected as light and dark change points, respectively, and the example of FIG. This indicates that a total of six change points can be detected. According to such an embodiment, since a certain number (two) of changing points are detected for each fine particle 45, the scattered state of the fine particles 45 can be more easily reflected more accurately.
In the case of the syringe 11 coated with silicon, a large number of light and dark change points are detected as described above.

  On the other hand, as shown in FIG. 6, in the case of the syringe 11 ′ not coated with silicon, silicon does not appear as a shade of gray in the grayscale image. Not.

It is preferable that the pixel size that can be detected as the boundary between the fine particles 45 can be set. For example, the pixel size is set to “5 pixels in the scanning direction A”. Then, the arrangement of the pixels parallel to the scanning direction A is “0, 0, 0, 0, 0, 50, 60, 30, 70, 70, 0, 0, 0, 0, 0” (the numerical value is the level of each pixel. In this case, the threshold is 30), between the fifth “0” and the sixth “50”, between the tenth “70” and the eleventh “0”. The boundary between “dark to light” and “light to dark” is detected, and “0, 0, 0, 0, 0, 50, 60, 0, 0, 0, 0, 0” (same as above) In such a case, the boundary can be prevented from being detected between the fifth “0” and the sixth “50” and between the seventh “60” and the eighth “0”.
According to this, it is possible to effectively eliminate noise other than the silicon fine particles 45 such as fine irregularities and scratches attached to the syringe 11. The pixel size is preferably set in consideration of the particle diameter of each silicon fine particle 45 and the like.

And the determination part 38 counts the number of the said detected change points, and the determination process of the application | coating state of the silicon | silicone in the syringe 11 is performed based on this. The storage unit of the inspection unit 35 stores in advance each normal determination criterion (upper limit value, lower limit value, or a certain numerical range) for each inspection, and the determination unit 38 counts this determination criterion and the above-described count. The quality of the syringe 11 is judged by comparing the number of change points.

As described above, according to the inspection apparatus 10, the silicon fine particles 45 that cannot originally appear in the grayscale image are clearly highlighted as a gray shade of halftone, and the boundary between the fine particles 45 due to the gradation difference from the background. Can be detected as a change point of light and dark. Therefore, based on the number of the change points, it is possible to easily and accurately inspect the application state of silicon such as whether or not silicon is applied to the syringe 11 or whether or not the application amount is appropriate.

According to the inspection apparatus 10, the inspection can be completed in about 50 (milliseconds) per syringe 11 from imaging by the imaging unit 30 to determination by the inspection unit 35.

An example of an inspection system configured using the inspection apparatus 10 as described above will be further described with reference to FIG. FIG. 7 is a schematic plan view showing the inspection system 60 according to the embodiment.

As illustrated in FIG. 7, the inspection system 60 includes star wheels 61 and 63, a rotary table 62, and the inspection device 10. The syringe 11 is conveyed in a row on the conveyor 65 with the distal end portion 15 facing downward, and is carried via the star wheel 61 to a rotary table 62 that rotates in synchronization with the star wheel 61. The loaded syringe 11 is coated with silicon on the inner wall surface 16 by the silicon coating machine 67 while moving with the rotation of the rotary table 62.

On the outer periphery of the rotary table 62, sandwiching pieces 70 for detachably sandwiching the body portion 12 of each syringe 11 are formed at equal intervals, and four sandwiching pieces 70 are connected to the arm 71 as a set. Has been. Each arm 71 is provided with an upside down means 72. The syringe 11 carried in from the star wheel 61 is turned over in a timely manner, and the nozzle 68 of the silicon coating machine 67 Silicone is sprayed from below the syringe 11 (flange 13 side). Silicon is uniformly sprayed from the nozzle 68 to reduce partial defects. The syringe 11 sprayed with silicon is further carried out through a star wheel 63 that rotates in synchronization with the rotary table 62 in a state where the syringe 11 is reversed in a timely manner and the distal end portion 15 is directed downward.

The illumination unit 20 and the slit plate 25 of the inspection apparatus 10 are fixed below the star wheel 63 in an appropriate direction, and the photographing unit 30 is disposed outside the star wheel 63. Since the flange portion 13 of the syringe 11 is hooked on the concave portion 64 of the star wheel 63, the syringe 11 is suspended vertically, and the syringe 11 includes the illumination unit 20, the slit plate 25, and the imaging unit. When passing between 30 and 30, the imaging unit 30 can intermittently take an image, and inspect the application state of silicon in the syringe 11 as described above.

Immediately after the syringe 11 that has passed through the inspection apparatus 10 is determined to be a non-defective product via a distribution unit that cooperates with a quality determination signal output from the inspection apparatus 10, the next process (filling of medicine) is performed by the conveyor 74. If the product is determined to be defective, it is discharged by the conveyor 75.
According to such an inspection system 60, it is possible to process 200 or more syringes 11 per minute.

If the inspection apparatus 10 is disposed near the silicon coating machine 67, there is a possibility that proper inspection cannot be performed due to the influence of scattered silicon. On the other hand, when a long time has elapsed since the silicon was applied, it becomes difficult for the inspection apparatus 10 to accurately detect the boundaries of the silicon microparticles 45. If it is the said inspection system 60, it will become possible to test | inspect the syringe 11 apply | coated with the silicon | silicone at a suitable position and timing.

An existing 5 ml plastic syringe was prepared, and an inspection experiment with the above-described inspection apparatus 10 was conducted using Sample A with a suitable amount (about 6 g) of silicon (360 Medical Fluid manufactured by Dow Corning) applied to the inner wall surface. .
Moreover, the same plastic syringe was prepared, and the test | inspection experiment by the said test | inspection apparatus 10 was done by making the thing which has not apply | coated silicon | silicone as the sample B.

FIG. 8 shows a grayscale image of sample A, and FIG. 9 shows an inspection image obtained by performing detection processing on the grayscale image.
FIG. 10 shows a grayscale image of sample B, and FIG. 11 shows an inspection image obtained by performing detection processing on the grayscale image.

  In this inspection experiment, as shown in FIG. 12, an inspection region 50 'was set, and the inspection region 50' was further divided into eight inspection blocks 1 to 8 to detect light and dark change points.

In sample A, the number of detected light and dark change points for each inspection block was as follows.
(1) 27 (2) 23 (3) 21 (4) 14 (5) 11 (6) 16 (7) 24 (8) 20; (total value of 1 to 8) 156

On the other hand, the number of detected brightness change points for each inspection block in sample B was as follows.
(1) 5 (2) 5 (3) 3 (4) 1 (5) 3 (6) 1 (7) 2 (8) 6 (total value of 1 to 8) 26

  As is clear from this result, in Sample A, a significantly larger number of change points were detected than in Sample B. In Sample B, the fact that a small number of light and dark change points are detected is considered to be due to fine irregularities or scratches on the syringe.

  In this inspection experiment, as a criterion for determining the quality of the syringe, “total value 50 of detected change points” is set in advance, sample A having a total value 156 is non-defective, sample B having a total value 26 Is judged as a defective product by the inspection apparatus 10. Further, in addition to these samples A and B, a plurality of samples were prepared and the test experiment was repeated. Similar results were obtained in accordance with the presence or absence of silicon coating.

  By setting appropriate judgment criteria in this way, it is possible to easily and accurately inspect whether or not silicon is applied to the syringe (whether silicon is applied or whether the amount of application is sufficient). It is understood. The determination criteria can be obtained by, for example, extracting and examining several syringes to which silicon is properly applied in advance and actually measuring the number of detected change points.

Furthermore, not only the qualitative inspection such as the presence / absence of silicon application as described above, but also a quantitative inspection such as what amount of silicon is applied can be applied by appropriately changing the determination criteria. .
In addition, based on the inspection data, for example, by creating a calibration curve using the least square method etc. with the vertical axis representing the number of detected change points (total value) and the horizontal axis representing the amount of silicon applied, It is also possible to estimate the amount of silicon applied from the number of detected change points.

The description of the above embodiment does not limit the present invention, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.
For example, in the above embodiment, the light and dark stripes 40 in which the bright part 41 and the dark part 42 are repeated are formed along the axial direction of the syringe 11. However, the light and dark stripes in the direction orthogonal to this are formed. May be. In addition, light and dark stripes can be formed diagonally.

Moreover, in the said embodiment, although the case where a silicon | silicone was apply | coated to the syringe 11 was illustrated and demonstrated, this invention is not limited to this, When applying the application | coating state of the transparent fine particle body in a transparent product is applied widely. be able to. The term “transparent” as used in the present invention is not only completely transparent but also a concept including translucency, which makes it difficult to determine the application state with the naked eye. The target product may have a plate shape or other shapes in addition to the cylindrical shape such as the syringe 11. Although there is no restriction | limiting also in a microparticles | fine-particles body, this invention exhibits the outstanding effect especially with respect to what was apply | coated with the mist form.

  The present invention can be widely used for inspection of the application state of transparent fine particles such as silicon in products such as syringes.

DESCRIPTION OF SYMBOLS 10 Inspection apparatus 11 Syringe 12 Body part 16 Inner wall surface 20 Illumination part 21, 21a Transmitted light 25 Slit plate 26 Translucent part 27 Light-shielding part 30 Imaging part 36 Image processing part 37 Detection part 38 Determination part 40 Bright / dark stripe 41 Bright part 42 Dark part 45 Particle 50 Inspection area A Scanning direction

Claims (6)

An inspection device for inspecting the application state of transparent fine particles in a product,
An illumination unit for illuminating the transmitted light;
A slit in which light-transmitting portions and light-shielding portions are alternately drilled, and is arranged between a product and the illumination portion, and forms bright and dark stripes in which bright and dark portions are alternately repeated on the product. The board,
An imaging unit that receives the transmitted light transmitted through the product and images the product;
An image processing unit that performs image processing on a captured image captured by the imaging unit to form a multi-tone gray image;
A detection unit that detects a boundary between the fine particles as a change point of light and dark according to a gradation difference between each fine particle of the transparent fine particle appearing in a halftone and the bright part or the dark part in the inspection region in the grayscale image; ,
An inspection apparatus comprising: a determination unit that determines a coating state of the transparent fine particle body based on the number of the change points. The inspection apparatus according to claim 1, wherein the detection unit is configured to detect the change point along a scanning direction parallel to the light and dark stripes. The inspection apparatus according to claim 2, wherein the detection unit detects the change points at both side edges along the scanning direction of the fine particles, thereby detecting two change points for each fine particle. . The inspection area is composed of a plurality of inspection blocks,
The detection unit detects the change point for each inspection block,
4. The determination unit according to claim 3, wherein the determination unit determines the application state of the transparent fine particle body by comparing a total value obtained by adding up the number of detected change points with a predetermined determination criterion. Inspection equipment. The product is a syringe,
5. The inspection apparatus according to claim 4, wherein the inspection state of the silicon coating on the inner wall surface of the syringe is inspected. An inspection method for inspecting the application state of transparent fine particles in a product,
Illuminating transmitted light to form bright and dark stripes in which bright and dark portions are alternately repeated on the product;
Receiving the transmitted light transmitted through the product and photographing the product;
A process of performing image processing on the captured image to form a multi-tone image,
Detecting the boundary of the fine particle as a change point of light and dark according to a gradation difference between each fine particle of the transparent fine particle body appearing in a halftone and the bright part or the dark part in the inspection region in the grayscale image;
And a step of determining a coating state of the transparent fine particle body based on the number of the change points.