JP2012167975A - Defect inspection method and defect inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a defect inspection method for accurately discriminating the types of defects.SOLUTION: Provided is a defect inspection method for inspecting defects based on image data obtained by picking up an image of an object to be inspected. The defect inspection method comprises the steps of: taking in plural types of image data of an object to be inspected; inspecting defects for each of the plural types of image data; and discriminating the type of the defect for a single defect in accordance with the combination of the image data from which the defect is inspected.

Description

  The present invention relates to a defect inspection method and a defect inspection apparatus, and more particularly to a defect inspection method and a defect inspection apparatus for various optical films and display filters used in display devices such as liquid crystal displays, organic EL displays, and plasma displays.

  Anti-reflection film, anti-glare film, near-infrared absorbing film, color adjustment film, polarizing plate, retardation film and other optical films, hard coat film, electromagnetic wave shielding film, conductive film, touch panel, or display having multiple functions as described above Filters are used in various display devices.

  An optical film or a filter for a display may have a defect that is rejected in the manufacturing process. Conventionally, inspection of these defects has been performed by visual inspection or optical system inspection.

  Visual inspection with the human eye has poor productivity and has problems such as variations in pass / fail judgment due to individual differences. In recent years, optical inspection using optical means has become widespread.

  As an optical system inspection method, a method of detecting a defect using a plurality of image data obtained by a plurality of optical systems has been proposed (for example, Patent Documents 1 and 2).

2003-329601 gazette 2008-116438 gazette

  However, Patent Document 1 uses a plurality of pieces of image data obtained by a plurality of imaging units in order to accurately inspect the number of occurrences of defects, but in order to avoid counting one defect repeatedly. When there are a plurality of image data at the same location, one of the image data is preferentially counted as one defect. That is, in Patent Document 1, a plurality of image data is processed independently, and one defect type is not determined by a combination of a plurality of image data.

  Patent Document 2 proposes a method in which two defect candidates (surface defects and bright spots) detected by two optical means are detected at the same coordinates, and only one detection result is applied. . Specifically, a method has been proposed that "when a surface defect and a bright spot are detected at the same time, it is not regarded as a defect". Here, surface defects are caused by nicks and internal foreign matter. A bright spot is a foreign substance adhering to the surface.

  That is, Patent Document 2 is an inspection method on the premise that a surface-attached foreign matter detected as a bright spot is not a defect, and image data for detecting a surface defect and an image for detecting a bright spot (surface-attached foreign matter). When the data exists at the same coordinates, the image data as the bright spot is preferentially processed as not being a defect.

  As described above, the inspection methods disclosed in Patent Documents 1 and 2 are to preferentially determine one of a plurality of image data, and combine a plurality of image data. It is not described that the type of one defect is discriminated.

  In the inspection methods disclosed in Patent Documents 1 and 2 described above, a problem may occur when a defect has a plurality of features.

  For example, when an optical film or the like has irregularities on the surface, the irregularities may have a color different from the color of the optical film due to the irregularities. Or, due to unevenness, the uneven portion may have a contrast different from that of the optical film. As described above, one defect may have two or more characteristics such as unevenness and color or contrast.

  It is usually difficult to detect such a plurality of features with one optical system, and it is necessary to detect with a plurality of optical systems. Patent Documents 1 and 2 use image data obtained by a plurality of optical systems, but ultimately one image data determined in advance is preferentially adopted. The feature of the defect is not determined by the combination. In other words, the inspection methods disclosed in Patent Documents 1 and 2 cannot accurately determine a defect having a plurality of features.

  The following inconvenience may occur when the types of defects having a plurality of features cannot be accurately identified.

  For example, when the surface irregularity defect candidate in an optical film or the like has a different color or different contrast, the pass / fail of the defect is determined only by image data obtained from one optical system that detects the unevenness, and the result is determined to be acceptable. Even so, the color or contrast image data may be at an unacceptable level. Also, the reverse is true. Further, depending on the type of defect, even if the uneven image data is at a reject level, if the color image data is at a pass level, the defect may have to be determined as pass.

  In other words, if the types of defects with multiple characteristics cannot be accurately identified, there is a risk that the defects that should be rejected are judged to be acceptable and there is a risk of overlooking them. May end up. In order to solve this problem, it is necessary to determine the type of defect and provide a pass / fail criterion for each defect type.

  On the other hand, until now, the automatic inspection apparatus has a function of detecting a defect targeted by the inspection apparatus, but has not been provided with a function of determining pass / fail as a final product.

  Accordingly, an object of the present invention is to provide a defect inspection method and a defect inspection apparatus that can accurately determine the type of defect. Another object of the present invention is to provide an automatic defect inspection method and an automatic defect inspection apparatus that accurately determine the type of defect of a roll product and perform pass / fail determination.

The above object of the present invention has been basically achieved by the following invention.
1) A method for inspecting defects based on image data obtained by imaging an object to be inspected,
Capture multiple species of image data for the inspected object,
Detect defects for each of these multiple types of image data,
A defect inspection method, wherein the type of defect is determined according to a combination of image data in which the defect is detected for one defect.
2) The defect inspection method according to 1), wherein the plurality of image data includes reflection image data and transmission image data.
3) The defect inspection method according to 2), wherein the transmission image data includes at least two image data selected from the group consisting of direct transmission image data, refractive transmission image data, and scattered transmission image data.
4) The defect inspection method according to any one of 1) to 3), wherein the defect size is further measured.
5) For each of the plurality of types of image data, a defect is detected and the strength and / or size of the detected defect is measured,
According to the combination of image data in which a defect is detected for one defect, the type of the defect is determined, and the strength and / or size of the defect in one image data of the image data in which the defect is detected. The defect inspection method according to claim 1, wherein pass / fail determination of the defect is performed based on the method.
6) The defect inspection method according to any one of 1) to 5), wherein the roll-shaped inspection object is imaged while being continuously conveyed.
7) The defect inspection method according to any one of 1) to 6), wherein the object to be inspected is a light-transmitting functional film or a display filter.
8) A plurality of imaging units that image the object to be inspected and generate image data;
The presence / absence of a defect is determined for each of the plurality of image data generated by the plurality of imaging units, a set pattern in which the determination result of the presence / absence of a defect of a plurality of image data for one defect is summarized is created, An image data processing unit that discriminates the type of defect according to the presence / absence collective pattern.
9) The defect inspection apparatus according to 8), wherein the image data processing unit further performs pass / fail determination for each determined defect type and creates defect data including at least the coordinate position of the defect.
10) The defect inspection apparatus according to 8) or 9), further including a display unit for displaying a defect position on the inspection object based on the defect data.

  According to the present invention, the types of defects having a plurality of characteristics can be accurately determined, so that defects that should be rejected are not missed, and the reliability of the final product is improved. In addition, according to a preferred aspect of the present invention, since the pass / fail determination is performed simultaneously with the defect inspection of the roll-shaped product, processing is performed based on the defect inspection result (for example, cutting into a sheet) at the customer to whom the roll-shaped product is delivered. All you have to do is reduce the burden of processing at the customer site.

The schematic side view of an example of the defect inspection apparatus for enforcing the defect inspection method of this invention.

  The defect inspection method of the present invention discriminates the type of defect based on a combination of a plurality of image data obtained by imaging an object to be inspected.

  The image data used in the present invention includes reflection image data, transmission image data, and the like. Further, reflection image data includes regular reflection image data, scattering reflection image data, and the like. Transmission image data includes direct transmission image data. Refracted transmission image data, scattered transmission image data, and the like. The present invention determines the type of defect by combining two or more of these image data.

  The specular reflection image data is obtained by disposing the light receiving unit at a position where it is specularly reflected with the incident light from the illumination unit with respect to the inspection object. The scattered reflection image data is obtained by disposing the light receiving unit at a position where incident light from the illumination unit scatters and reflects on the object to be inspected. The direct transmission image data is obtained by arranging the illumination unit and the light receiving unit in a vertical position with the object to be inspected in between. The refracted transmission image data is obtained by shifting the illumination unit and the light receiving unit in a vertical position with the object to be inspected in between. The scattered transmission image data is obtained by arranging an illumination unit in an oblique direction and a light receiving unit in a vertical direction with an object to be inspected in between.

  In the present invention, it is preferable to use a combination of at least reflection image data and transmission image data. In this case, either one or both of regular reflection image data and scattered reflection image data can be used as the reflection image data, and the transmission image data includes a direct transmission image data, a refractive transmission image data, and a scattering transmission image data. At least one selected image data can be used.

  In the present invention, it is preferable to use at least regular reflection image data as reflection image data.

  In the present invention, it is preferable to use at least two image data selected from direct transmission image data, refractive transmission image data, and scattered transmission image data as transmission image data, and at least direct transmission image data and refractive transmission data. It is preferable to use image data, and it is particularly preferable to use direct transmission image data, refractive transmission image data, and scattered transmission image data.

  The combination of the image data described above makes it possible to more accurately determine the type of defect particularly in a light-transmitting functional film or a display filter.

  A preferred embodiment of a defect inspection apparatus for carrying out the defect inspection method of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic side view of an example of a defect inspection apparatus for carrying out the defect inspection method of the present invention.

  In FIG. 1, the roll-shaped product 1 that is an object to be inspected is unwound from the unwinding unit 2 and taken up by the winding and winding unit 3 to image the rolled product 1 and generate image data. The first imaging unit 10, the second imaging unit 20, the third imaging unit 30, and the fourth imaging unit 40, which are imaging units for doing so, are arranged. In the above four image pickup units, an illumination unit (reference numerals 11, 21, 31, 41) and a light receiving part (reference numerals 12, 22, 32, 42) for irradiating the roll-shaped product 1 with light are respectively arranged. .

  The first imaging unit 10 is a specular reflection image data, the second imaging unit 20 is a refractive transmission image, the third imaging unit 30 is a direct transmission image data, and the fourth imaging unit 40 is an imaging device for obtaining scattered transmission image data. .

  The image data picked up by the first to fourth image pickup units is sent to the image data processing unit 50 and subjected to image processing to determine the defect type, and a pass / fail determination is made for each defect type. Defect data created by the image data processing unit 50 (for example, defect coordinate position, defect type, defect level, etc.) is sent to the display unit 60 together with being stored. The display unit 60 displays the defect position on the rolled product 1 based on the defect data. Only one of the storage of the defect data and the display on the roll-shaped product may be performed.

  The defect inspection method and the defect inspection apparatus of the present invention are preferably performed continuously and automatically while continuously transporting a roll-shaped product, and preferably have a pass / fail determination function as described above.

  Hereinafter, the main part which comprises the defect inspection apparatus of this invention is demonstrated in detail.

  The unwinding unit 2 is a device that unwinds the roll-shaped product 1 wound around the core at a constant speed. For this reason, a mechanism for measuring the unwinding length is provided in order to keep the transport speed constant together with the winding unit 3 and to determine the coordinates of the detected defect position in the transport direction length of the rolled product 1.

  Further, the unwinding unit 2 is configured to prevent the positional deviation of the film 1a in the width direction of the film 1a to be conveyed (a roll-shaped product being unwound and conveyed is referred to as “film” for convenience) 1a. A mechanism (edge position sensor) for measuring the edge position and adjusting the unwinding position according to the change is provided. Further, the unwinding unit 2 is provided with a mechanism for controlling the tension so that the film 1a conveyed together with the winding unit 3 does not sag.

  The winding unit 3 is a device that winds the conveyed film 1a around the core again. The winding unit 3 has functions similar to those of the unwinding unit 2, such as an edge position sensor and a tension control mechanism.

  In the first to fourth imaging sections (reference numerals 10, 20, 30, 40), the illumination sections (reference numerals 11, 21, 31, 41) can use metal halide lamps or LED lamps as light sources. In addition, in order to prevent unintended irradiation from occurring in other imaging units in each imaging unit, the lens is used to direct the light to the light receiving unit, and light from the light source is passed through a slit (not shown). It is preferable to irradiate the film 1a (inspected object). The light receiving section (reference numerals 12, 22, 32, 42) can use a CCD image sensor or the like as the light receiving means.

  The first imaging unit 10 is an imaging device for obtaining specular reflection image data, and the light receiving unit 12 receives specular reflection light from the film 1a (inspection object). The irradiation angle from the illuminating unit 11 and the light receiving angle of the light receiving unit 12 are preferably in the range of 30 to 70 degrees with respect to the film 1a (inspected object), and more preferably in the range of 40 to 50 degrees.

  The second imaging unit 20 is an imaging device for obtaining refractive transmission image data, and the light receiving unit 22 receives refracted light from the film 1a (inspected object). The illuminating unit 21 and the light receiving unit 22 face the film 1a (inspected object) in the vertical direction, and the intersection of the perpendicular line and the film 1a that is lowered from each position toward the film 1a (inspected object) is the film. It arrange | positions so that it may rank with a straight line along the conveyance direction of 1a. The intersection is preferably 1 to 5 mm away, more preferably 1 to 2 mm away. In addition, it is a more preferable form that a slit (not shown) is provided in the light receiving portion so as to receive only refracted light, and light other than the refracted light is shielded.

  The third imaging unit 30 is an imaging device for directly obtaining transmission image data, and the light receiving unit 32 receives the transmitted light from the film 1a (inspected object). The illumination unit 31 and the light receiving unit 32 are arranged to face each other in the vertical direction with respect to the film 1a (inspected object).

  The fourth imaging unit 40 is an imaging device for obtaining scattered transmission image data, and the light receiving unit 42 receives scattered light from the film 1a (inspected object). The irradiation angle from the illumination unit 41 is preferably in the range of 1 to 10 degrees and more preferably in the range of 3 to 7 degrees with respect to the vertical line orthogonal to the film 1a (inspected object). The light receiving angle of the light receiving unit 22 is perpendicular to the film 1a. In addition, it is a more preferable form to direct illumination light to receive only scattered light.

  The first to fourth imaging units are arranged so as to correspond to the entire area in the width direction of the film 1a which is an object to be inspected. It is also possible to divide the imaging unit into a plurality in parallel with respect to the transport direction. For example, with respect to a width of 1000 mm of the film 1a that is an object to be inspected, an illumination unit comprising a light source having an effective irradiation width of 500 mm, a light receiving unit having a light receiving element having a resolution of 5,000 pixels, and a defect to be inspected When the width is 0.1 mm, it is necessary to arrange at least two irradiation units and light receiving units.

  Arranging more light receiving units in parallel with respect to the transport direction is a preferable mode for observing defects in detail, and enables more detailed observation.

  The CCD image sensor or the like as the light receiving means can select the operation speed based on the feed speed of the film 1a as the inspection object.

  Image data captured by the first to fourth imaging units is sent to the image data processing unit 50. The image data processing unit 50 performs the following processing.

  (I) For image data output from each imaging unit, a defect is detected based on a threshold set for each imaging unit, and when a defect is detected, “defect exists”, the size parameter of the defect (Area, length, height, etc.) and detection coordinate information of the defect are output. The threshold value can be set based on intensity parameters (reflectance, transmitted light amount, etc.) constituting each image data. In addition, what was detected as a defect at this stage is determined to be acceptable at stage (iv), which will be described later, and includes those that have no problem even if they are included in the product.

  (Ii) Based on the detection coordinates of the defects detected in the respective image data, whether or not defects are detected in the respective image data for the same defect is summarized.

  In the case of the defect inspection apparatus of FIG. 1, whether or not defects are detected in each of the image data obtained by the first to fourth imaging units for one defect is summarized as shown in Table 1 described later. It is output as a collective pattern with and without defect detection. In Table 1, a collective pattern is created based on the presence or absence of defects in the other three image data excluding the scattered transmission image data (image data obtained by the fourth imaging unit).

  (Iii) Based on the set pattern of the presence / absence of defects, the type of defect is determined according to the relationship between the preset defect type and the set pattern.

(Iv) Based on a pass / fail criterion set in advance for each type of defect, pass / fail determination of the defect is performed.
Here, the pass / fail judgment criteria include, for each type of defect, which image data of the detected image data is used for the pass / fail judgment, and the defect size parameters (area, length) in the image data. Pass / fail criteria based on height, etc.).

  (V) Outputting the pass / fail judgment result of the detected defect as an output.

  The greatest feature of the present invention is that the image processing of (ii) and (iii) above is performed, and what kind of image data is to be combined is appropriately selected according to the type and application of the object to be inspected. Can do.

  Some examples of the relationship between defect types (features) and image data are given below.

  1) Regular reflection image data uses light that is incident on the object to be inspected from an oblique direction and specularly reflected on the surface of the object to be inspected, and has a reflectance different from that of a convex defect or a normal part. It is possible to detect the defects that it has. However, a defect that does not change the reflected light, for example, a defect that is not exposed on the surface of the inspection object and is buried in the inspection object may not be detected.

  2) Refractive transmission image data uses a phenomenon in which light is refracted and transmitted in a direction different from that of a normal part because the path of incident light to an object to be inspected is changed by a defect. The shape defect and the dent defect can be detected. However, a defect that is not accompanied by refraction of incident light, for example, without unevenness, may not be detected.

  3) Direct transmission image data uses a change in the amount of transmitted light when incident light passes through the object to be inspected. Light-absorbing defects (for example, colored foreign matters) existing inside or on the surface of the object to be inspected Light transmissive defects (for example, color loss) and defects that exist on the surface of the object to be inspected and reflect or scatter light to reduce the amount of transmitted light (for example, colored deposits without thickness) can be detected. However, a defect that does not change the amount of transmitted light (for example, a dent that does not change density) may not be detected.

  4) Scattered transmission image data uses the fact that light incident on the object to be inspected is scattered by a defect in the process of transmission, and the size of the protruding defect is converted into specular reflection image data or refractive transmission image data. Compared to this, it can be measured more accurately.

  A defect can be detected from the various image data described above using an intensity parameter (reflectance, transmitted light amount, etc.), and the size of the defect can be measured using a size parameter (area, length, height, etc.).

  In the present invention, it is preferable that the defect acceptance / rejection determination process is performed based on the size parameter. According to the present invention, the type of defect is determined by a combination of a plurality of image data, and the pass / fail determination of the defect whose type is determined is based on the size parameter of one image data set in advance for each type of defect. It is preferable to perform a pass / fail determination process for defects based on the above.

  The present invention discriminates the type of defect from a set pattern of a plurality of image data. Table 1 shows some examples. However, the present invention is not limited to these examples.

  Table 1 shows the relationship between the collective pattern of the presence / absence of defects and the type of defect, and specular reflection image data, refractive transmission image data, and direct transmission image data are used as the image data. In the table, ◯ indicates that the defect can be detected, and x indicates that it cannot be detected.

  The collective pattern 1 is non-detection (×) for specular reflection image data, detection (◯) for refraction transmission image data, and non-detection (×) for direct transmission image data. The type is identified as “simple dent defect”. Hereinafter, the collective patterns 2 to 6 are the same as described above.

  When the defect type is determined, a pass / fail determination is then made in accordance with a criterion preset for each defect type. This pass / fail determination is made based on a defect size parameter in the image data set in advance. In Table 1, the pass / fail determination image data of the collective pattern 1 is directly transmitted image data. Hereinafter, the image data used for the pass / fail determination is similarly set and input in advance for the collective patterns 2 to 6.

  It is preferable that the image data used for determining whether or not the defect is acceptable is appropriately selected depending on the application and type of the object to be inspected. For example, optical films and display filters are mounted on the front of the display, and viewers view the display image as a transparent image through these films and filters, so defects detected in the transmitted image data are judged more severely. Therefore, it is preferable to use directly transmitted image data or refracted image data as image data serving as a reference for determining whether or not a defect is acceptable.

  In the present invention, it is further preferable to make a pass / fail determination according to the number of defects per unit area for each defect level. Here, the defect level is determined by the size of the defect. For example, defects having a specific size or more are set to defect level A, and defects having a certain size range are set to defect level B.

  The meaning of determining the defect level is, for example, that the defect level A is unconditionally impossible due to the presence of one, but the defect level B is unacceptable up to one per unit area and not more than two. This is to apply to the pass / fail judgment method.

  The defect level discrimination criteria may be set uniformly regardless of the defect type, but it is preferable to provide a defect level discrimination standard for each defect type. The defect level determination criteria may differ depending on the defect type. By providing a defect level determination criterion for each defect type, it is possible to perform pass / fail determination with higher accuracy. For example, in Table 1, the refraction transmission image data is used as the pass / fail determination image data for the collective pattern 1 and the collective pattern 3, but the defect level discrimination criteria are different between the collective pattern 1 and the collective pattern 3. Also good.

Regarding the determination of the defect level, specifically, for example, in the case of a “simple dent defect” detected and determined by the collective pattern 1 in Table 1 above, a defect having an area of 3 mm ² or more is determined as the defect level A 1 A defect with an area of 0.2 mm ² or more and less than 3 mm ² is determined as defect level B, and ^two or more defects per unit area (0.5 m ² ) are rejected (up to one is acceptable). An area of less than 0.2 mm ² is not detected as a defect.

  As described above, the defect data obtained by the image data processing unit 50 is sent to the display unit 60, and the defect position is displayed (marked) on the conveyed film 1a. Here, the defect data sent to the display unit 60 includes at least the coordinate position of the defect, but can include a defect type and a defect level as necessary, and the defect type indicates the defect level at the same time as the coordinate position. Can be displayed.

  Examples of the display method in the display unit 60 include a method of directly marking the defect position of the film 1a and a method of marking the end (ear part) of the film 1a at the same position as the defect position in the transport direction. Examples of the display means include a device for applying a label such as a seal, an ink jet device, a device for scratching the end (ear portion) of the film 1a with a laser or a cutter, and the like.

  Further, the image data processing unit 50 may have a function of storing the created defect data and a function of displaying or printing the stored defect data on a display or a paper medium.

  The present invention is suitable for inspection of defects such as light-transmitting functional films (various optical films) and display filters. In the above functional film and display filter, there are many types of defects, and the defect type can be determined by using the defect inspection method of the present invention. Therefore, the pass / fail determination is performed according to the type of defect. Therefore, it is possible to realize highly accurate defect inspection.

  Examples of the light-transmitting functional film include an antireflection film, an antiglare film, a near-infrared absorption film, a color adjustment film, a polarizing plate, a retardation film, a field-of-view film, an optical film such as a light control film, and a hard coat. A film, an electromagnetic shielding film, a conductive film, a touch panel, etc. are mentioned.

  The display filter is a filter disposed on the front surface of a display such as a liquid crystal display, an organic EL display, a plasma display, etc., and the above-mentioned filter for a display in which one or a plurality of the above functional films are combined or a single base film. And a display filter in which a plurality of functional layers of the functional film are laminated.

  For example, a display filter used in a plasma display is generally a display filter having a plurality of functions. As such a display filter, an antireflection function, an antiglare function, a hard coat function, a near infrared absorption function, Examples include those having at least two functions selected from a color adjustment function and an electromagnetic wave shielding function.

  Examples of the plasma display filter include an antireflection / near infrared absorption film, an antireflection / color adjustment film, an antireflection / near infrared absorption / color adjustment film, an antireflection / near infrared absorption / electromagnetic shielding film, an antireflection / Near-infrared absorption / color adjustment / electromagnetic shielding film, anti-glare / near infrared absorption film, anti-glare / color adjustment film, anti-glare / near infrared absorption / color adjustment film, anti-glare / near infrared absorption / electromagnetic shielding film, anti-glare・ Near-infrared absorption / color adjustment / electromagnetic wave shielding film, hard coat / near infrared absorption film, hard coat / color adjustment film, hard coat / near infrared absorption / color adjustment film, hard coat / near infrared absorption / electromagnetic shielding film, hard Examples include coats, near infrared absorption, color adjustment, and electromagnetic shielding films. It is.

  The above-mentioned display filter having a plurality of functions may be one in which a plurality of functional films are bonded with an adhesive or the like, or a plurality of functional layers laminated on one base film. It may be.

  The present invention is suitable for defect inspection of a display filter having a plurality of functions, and particularly suitable for a display filter in which a plurality of functional layers are laminated on only one base film.

Some examples of the configuration of the display filter in which a plurality of functional layers are laminated on only one base film are exemplified below.
1) Adhesive layer / Near-infrared absorbing layer / Base film / Hard coat layer 2) Adhesive layer / Near infrared absorbing layer / Base film / Hard coat layer / Antireflection layer 3) Adhesive having near-infrared absorbing function Layer / near-infrared absorbing layer / base film / hard coat layer 4) pressure-sensitive adhesive layer having a near-infrared absorbing function / near infrared absorbing layer / base film / hard coat layer / antireflection layer 5) pressure-sensitive adhesive layer / near infrared Absorbing layer / base film / electromagnetic wave shield layer / hard coat layer 6) adhesive layer / near infrared absorbing layer / base film / electromagnetic wave shield layer / hard coat layer / antireflection layer 7) adhesive having a near infrared absorbing function Layer / base film / electromagnetic wave shield layer / hard coat layer 8) pressure-sensitive adhesive layer having a near infrared absorption function / base film / electromagnetic wave shield layer / hard coat layer / antireflection layer.

  In addition, the said near-infrared absorption layer or the adhesive layer which has a near-infrared absorption function can have a color adjustment function together. In addition, the display filter may have a release film or protective film laminated on the surface of the display filter in the manufacturing process or physical distribution process, but these release film and protective film are eventually peeled off. Since it is removed, it is excluded from the above configuration example.

  As the base film, a polyethylene terephthalate film having a thickness of 50 to 300 μm is preferably used.

1 Roll product (inspected object)
DESCRIPTION OF SYMBOLS 1a Film in which roll-shaped product is unwound and conveyed 2 Unwinding part 3 Winding part 10 1st imaging part 20 2nd imaging part 30 3rd imaging part 40 4th imaging part 11, 21, 31, 41 Illumination part 12, 22, 32, 42 Light receiving unit 50 Image data processing unit 60 Display unit

Claims (10)

A method for inspecting defects based on image data obtained by imaging an object to be inspected,
Capture multiple species of image data for the inspected object,
Detect defects for each of these multiple types of image data,
A defect inspection method, wherein the type of defect is determined according to a combination of image data in which the defect is detected for one defect.   The defect inspection method according to claim 1, wherein the plurality of image data includes reflection image data and transmission image data.   The defect inspection method according to claim 2, wherein the transmission image data includes at least two image data selected from the group consisting of direct transmission image data, refractive transmission image data, and scattered transmission image data.   Furthermore, the defect inspection method in any one of Claims 1-3 which measures the size of a defect. For each of the plurality of types of image data, a defect is detected, and the intensity and / or size of the detected defect is measured,
According to the combination of image data in which a defect is detected for one defect, the type of the defect is determined, and the strength and / or size of the defect in one image data of the image data in which the defect is detected. The defect inspection method according to claim 1, wherein pass / fail determination of the defect is performed based on the method.   The defect inspection method according to claim 1, wherein the roll-shaped inspection object is imaged while being continuously conveyed.   The defect inspection method according to claim 1, wherein the object to be inspected is a light-transmitting functional film or a display filter. A plurality of imaging units for imaging the inspected object and generating image data;
The presence / absence of a defect is determined for each of the plurality of image data generated by the plurality of imaging units, a set pattern in which the determination result of the presence / absence of a defect of a plurality of image data for one defect is summarized is created, An image data processing unit that discriminates the type of defect according to the presence / absence collective pattern.   The defect inspection apparatus according to claim 8, wherein the image data processing unit further determines pass / fail for each determined defect type, and creates defect data including at least the coordinate position of the defect.   The defect inspection apparatus of Claim 8 or 9 which has a display part for displaying a defect position on a to-be-inspected object based on the said defect data.

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