Inspection system, inspection device, inspection method, and ultraviolet ray transmission prevention glass production method

Abstract

Abnormalities on one surface of an object to be inspected, for example, on a surface covered with an ultraviolet light transmission preventing layer, are accurately detected. [Solution] A light source irradiates inspection light onto a first surface, which is one of the surfaces of an object to be inspected, including glass, and a detector detects the intensity of scattered light generated on the first surface. A judgment unit judges whether or not there is an abnormality on the first surface based on the detected intensity. The inspection light includes wavelength components whose transmittance of the object to be inspected is lower than a predetermined reference transmittance. Embodiments of the present application can be realized in any of the following forms: an inspection system, an inspection device, an inspection method, and a method for producing UV-blocking glass.

Description

[Technical Field]

[0001] The present application relates to an inspection system, an inspection device, an inspection method, and a method for producing ultraviolet ray-blocking glass.The present application relates to a technique for determining abnormalities on the surface of an object to be inspected, for example, including glass. [Background technology]

[0002] Ultraviolet (hereinafter sometimes referred to as "UV") blocking glass is made by covering the surface of a glass substrate with an ultraviolet blocking coating. Ultraviolet blocking glass is also called ultraviolet cut glass. During the process from production to shipping of ultraviolet blocking glass, foreign matter may adhere to the coated surface of the glass substrate that is covered with the ultraviolet blocking coating. Foreign matter that adheres during the production process may become fixed to the ultraviolet blocking coating. This fixation of foreign matter can cause a loss of quality. However, foreign matter does not fixate on the non-coated surface of the glass substrate that is not covered with the ultraviolet blocking coating, so it does not affect the quality of the ultraviolet blocking glass. For this reason, the non-coated surface is sometimes excluded from inspection, and only the coated surface is inspected.

[0003] Inspection methods that use a light source that irradiates visible light and a camera that is sensitive to the visible light range will detect foreign matter attached to both the coated and uncoated surfaces.In this regard, the inspection method described in Patent Document 1 uses a specular reflection optical system consisting of an ultraviolet irradiator and a detector capable of detecting ultraviolet wavelengths to detect defects on the surface of a resin film that is transparent to visible light but opaque to ultraviolet wavelengths. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5866691 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the inspection method described in Patent Document 1 is intended to inspect resin films and cannot be applied to inspecting UV-blocking glass. Furthermore, UV-blocking glass for automobiles is required to have high mechanical durability against scratches and abrasion, and to have stable quality despite external environmental factors such as temperature and moisture. Therefore, resin films cannot be used as a substitute for UV-blocking glass. The present application has been made in consideration of the above points, and aims to provide an inspection system, an inspection device, an inspection method, and a method for producing ultraviolet-resistant glass that can accurately detect abnormalities on one side of the surface of an object to be inspected, for example, the side covered with an ultraviolet-resistant layer. [Means for solving the problem]

[0006] (1) The present application has been made to solve the above-mentioned problems, and a first aspect of the present application is an inspection system comprising a light source that irradiates inspection light onto a first surface, which is one of the surfaces of an object to be inspected, including glass; a detector that detects the intensity of scattered light generated on the first surface; and a judgment unit that judges the presence or absence of an abnormality on the first surface based on the intensity, wherein the inspection light includes wavelength components whose transmittance of the object to be inspected is lower than a predetermined reference transmittance.

[0007] (2) A second aspect of the present application is an inspection device that includes a light source that irradiates inspection light onto a first surface, which is one of the surfaces of an object to be inspected, a detector that detects the intensity of scattered light generated on the first surface, and a judgment unit that judges whether or not there is an abnormality on the first surface based on the intensity, wherein the inspection light includes wavelength components whose transmittance of the object to be inspected is lower than a predetermined reference transmittance.

[0008] (3) A third aspect of the present application is an inspection method in an inspection system, in which inspection light is irradiated from a light source onto a first surface, which is one of the surfaces of an object to be inspected; a detector detects the intensity of scattered light generated on the first surface; and a judgment unit judges whether there is an abnormality on the first surface based on the intensity, and the inspection light includes wavelength components whose transmittance of the object to be inspected is lower than a predetermined reference transmittance.

[0009] (4) A fourth aspect of the present application may be a method for producing ultraviolet ray-blocking glass, which includes the steps of covering a glass substrate with an ultraviolet ray-blocking layer to produce the test object, and performing the inspection method described in (3). [Effects of the Invention]

[0010] According to the present invention, an abnormality on one side of the surface of an object to be inspected can be accurately detected. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram showing a first configuration example of an inspection system according to the present embodiment. [Figure 2] FIG. 2 is a schematic block diagram showing an example of the functional configuration of an inspection device according to the present embodiment. [Figure 3] FIG. 2 is a diagram illustrating wavelength characteristics of transmittance of UV-blocking glass. [Figure 4] 5A and 5B are diagrams showing an example of detection of scattered light from a first surface and a second surface of an object under inspection according to the present embodiment. [Figure 5] 10 is a diagram illustrating an example of the ratio of luminance on a first surface and a second surface of an object under inspection for each wavelength of inspection light from a light source. [Figure 6] FIG. 2 is a diagram illustrating the spectral characteristics of a visible light cut filter. [Figure 7] 3A and 3B are diagrams illustrating examples of images of a first surface and a second surface of an object under test. [Figure 8] 10A and 10B are diagrams illustrating the spectral characteristics of inspection light and scattered light; [Figure 9] FIG. 10 is a diagram illustrating another example of the spectral characteristics of a filter. [Figure 10] 1 is a flowchart illustrating an inspection method according to the present embodiment. [Figure 11] FIG. 2 is a schematic diagram showing a second configuration example of the inspection system according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, the configuration of this embodiment will be described. Fig. 1 is a schematic diagram showing a first configuration example of an inspection system according to this embodiment. The inspection system S1 according to this embodiment includes an inspection device 10, a light source 20, and a detector 30. The object to be inspected by the inspection system S1 is primarily a glass plate or a product that includes a glass plate as a material. The product is not limited to a final product, but may also include intermediate products generated in the production process. In this application, the object to be inspected may be referred to as an "inspection subject Sp." The object to be inspected may also be referred to as a sample.

[0013] The intensity of scattered light generated on the surface of the object Sp to be inspected is transmitted from the detector 30 to the inspection device 10. The inspection device 10 determines abnormalities on the surface of the object Sp to be inspected. The functions of the inspection device 10 are realized, for example, by causing a personal computer (PC) to execute a predetermined program. The inspection device 10 may also be realized using a general-purpose information device other than a PC, such as a tablet terminal device, a smartphone, or a workstation. The inspection device 10 may also be configured using dedicated hardware. The following description will mainly focus on the case where the functions of the inspection device 10 are realized by a PC.

[0014] The light source 20 irradiates the inspection light toward the inspection object Sp. The inspection light includes wavelength components whose transmittance through the inspection object Sp is lower than a predetermined reference transmittance. The reference transmittance is a transmittance (e.g., 1 to 5%) at which the intensity of the transmitted light is considered to be sufficiently attenuated compared to the incident light. If the inspection object Sp is a glass plate, the inspection light includes a component with a wavelength of, for example, 400 nm. This wavelength component includes ultraviolet A rays (UVA) of near-ultraviolet rays and wavelength components of a color perceived as purple by human vision.

[0015] The light source includes a light-emitting element and an illumination lens. The light-emitting element emits light in response to the supply of power. The light-emitting element is, for example, a light-emitting diode (LED). The illumination lens converges the inspection light emitted from the light source 20 onto the surface of the object Sp to be inspected. The intensity of the light source 20 is set to a predetermined constant reference intensity. In this application, the area on the surface of the object Sp to be inspected that is illuminated with the inspection light from the light source 20 may be referred to as the "illumination area." Furthermore, the surface of the object Sp to be inspected that is oriented vertically or in a direction close to the vertical may be referred to as the "bottom surface." The "bottom surface" is used to distinguish it from the "top surface," which is the surface oriented in the opposite direction to the "bottom surface."

[0016] The detector 30 detects the intensity of scattered light incident from the object under inspection Sp. The configuration example illustrated in Figure 1 enables reflective dark-field observation of the surface of the object under inspection Sp. Light coming from sources other than the light source 20 is blocked around the inspection system S1. Inspection light from the light source 20 is incident at an acute angle to the top surface of the object under inspection Sp, and reflected light is reflected in a direction symmetrical to the incident direction with respect to the normal direction from the illuminated area, while scattered light is diffused in other directions. The detector 30 is installed in the normal direction of the illuminated area. At this position, reflected light from the illuminated area is not incident, and the detector 30 is installed at a position where scattered light is incident.

[0017] Scattered light generated in the irradiation area is incident on the detector 30. The detector 30 is equipped with a photosensitive element that can detect the intensity of light. A line camera (also called a "line sensor") is used as the detector 30. The line camera detects the intensity of light emitted from each part of the moving inspection object Sp at regular time intervals using multiple light-receiving elements that are arranged one-dimensionally, and can acquire a two-dimensional image representing the distribution of shades. A consumer digital camera may also be used as the detector 30. The detector 30 outputs a detection signal indicating the intensity of the detected light to the inspection device 10. The light source 20 and the detector 30 are installed in a direction facing the upper surface of the object under test Sp. The light source 20 and the detector 30 may each be suspended from the ceiling.

[0018] The specimen Sp is a UV-blocking glass. The UV-blocking glass is configured such that one surface of the glass substrate is covered with a UV-blocking coating. The UV-blocking coating is a layer primarily composed of a material that absorbs or scatters ultraviolet light. The UV-blocking coating may be an organic material such as a benzophenone compound, an inorganic material such as titanium oxide, zinc oxide, or cerium oxide, or a mixture of these materials. The UV-blocking coating can be formed, for example, by applying a UV-blocking paint containing the above material to one surface of the glass substrate and allowing the applied UV-blocking paint to solidify. In this application, the UV-blocking coating may be simply referred to as the "paint." The surface of the specimen Sp that is covered with the paint may be referred to as the "coated surface," and the surface that is not covered with the paint may be referred to as the "non-coated surface." The orientation of the coated surface may be constant or variable. In the present application, a case may be exemplified in which the coating surface CS is the top surface and the non-coating surface NS is the bottom surface, the first surface is the top surface, and the second surface is the bottom surface.

[0019] Next, an example of the functional configuration of the inspection device 10 according to this embodiment will be described. Fig. 2 is a schematic block diagram showing an example of the functional configuration of the inspection device 10 according to this embodiment. The inspection device 10 includes a control unit 110 , an input / output unit 140 , an operation unit 150 , a display unit 160 , and a storage unit 170 . The control unit 110 executes processes for realizing the functions of the inspection device 10 and processes for controlling those functions. The control unit 110 may include general-purpose components such as a processor and be configured as a computer. The processor reads a program previously stored in the storage unit 170 and performs processes instructed by instructions written in the read program to realize the functions. In this application, performing processes instructed by instructions written in a program may be referred to as program execution, etc. Part or all of the control unit 110 is not limited to general-purpose hardware such as a processor, and may be configured to include dedicated hardware such as an LSI (Large Scale Integration) or an ASIC (Application Specific Integrated Circuit). Functional units that realize the functions of the control unit 110 will be described later.

[0020] The input / output unit 140 is connected to other devices wirelessly or via a wire to input and output various types of data. The input / output unit 140 includes, for example, an input / output interface or a communication interface. The input / output unit 140 is connected to, for example, the light source 20 and the detector 30.

[0021] The operation unit 150 receives a user operation and generates an operation signal corresponding to the received operation. The operation unit 150 may include dedicated components such as buttons, knobs, and dials, or general-purpose components such as a mouse and keyboard. The operation unit 150 may be an input interface that receives an operation signal wirelessly or via a wired connection from another device. The other device may be, for example, a portable device such as a remote controller or a multi-function mobile phone. The operation unit 150 outputs the acquired operation signal to the control unit 110.

[0022] Display unit 160 displays display information such as images, characters, and symbols based on display data input from control unit 110. Display unit 160 may include, for example, a liquid crystal display, an organic electroluminescence display, or the like.

[0023] In addition to the above programs, the storage unit 170 stores various data used in the processes executed by the control unit 110 and various data acquired by the control unit 110. The storage unit 170 includes a non-volatile (non-temporary) storage medium such as a ROM (Read Only Memory), a flash memory, or an HDD (Hard Disk Drive). The storage unit 170 also includes a volatile storage medium such as a RAM (Random Access Memory), a register, or the like.

[0024] The control unit 110 includes a measurement control unit 112, a determination unit 114, and a display processing unit . The measurement control unit 112 controls the measurement of scattered light generated on the surface of the specimen Sp. For example, when a measurement is instructed in response to an operation by an operator, the measurement control unit 112 irradiates the surface of the specimen Sp with inspection light from the light source 20 and causes the detector 30 to detect the incident scattered light.

[0025] The determination unit 114 acquires a detection signal indicating the intensity distribution of scattered light generated on the surface of the object Sp from the detector 30. When a line camera is used as the detector 30, the determination unit 114 can identify each part on the surface of the object Sp using pixels. In general, a line camera has multiple light receiving elements, and the multiple light receiving elements are arranged one-dimensionally on the imaging surface.

[0026] The determination unit 114 determines whether or not an abnormality has occurred on the coated surface of the test subject Sp based on the intensity detected for each region. The determination unit 114 identifies, for example, a region where the intensity is higher than a predetermined reference intensity as a high-intensity region. The reference intensity is a reference value of intensity for determining a region where a higher intensity is obtained as a high-intensity region. The determination unit 114 identifies each group of spatially continuous high-intensity regions as a candidate region. Because the intensity of the scattered light arriving from a candidate region is higher than that of the surrounding region, it is estimated that there is a high possibility that an abnormality such as the attachment of a foreign substance or unevenness has occurred.

[0027] The determination unit 114 determines whether the size of the identified candidate region exceeds a predetermined reference size, and identifies a candidate region having a size exceeding the reference size as an abnormal region. The reference size is a reference value for determining a larger candidate region as an abnormal region. The reference size may be defined for each type of abnormality along with the shape of the abnormal region. The determination unit 114 determines that an abnormality exists when the test subject Sp has an abnormal region. The determination unit 114 determines that an abnormality does not exist when the test subject Sp does not have an abnormal region. The determination unit 114 outputs determination information indicating the presence or absence of an abnormality to the display processing unit 116.

[0028] The display processing unit 116 configures various display screens and outputs display data showing the configured display screens to the display unit 160. The display unit 160 displays the display screens based on the display data input from the display processing unit 116. The display screen may include, for example, a guide display for performing a measurement. Specifically, a measurement button may be arranged on the display screen. The measurement button is an example of a screen component for instructing a measurement by operation. When detecting that the measurement button is pressed, the measurement control unit 112 determines that a measurement has been instructed. For example, the measurement control unit 112 detects that the measurement button has been pressed when the position indicated by the operation signal input from the operation unit 150 indicates a position within the measurement button.

[0029] The display screen may include the measurement results obtained by the above-mentioned measurements. Specifically, the display processing unit 116 includes the determination information input from the determination unit 114 on the display screen. When a detection signal indicating a captured image of the surface of the specimen Sp is acquired from the detector 30, the display processing unit 116 may display the captured image together with the determination information on the display screen.

[0030] Next, the principle of anomaly detection according to this embodiment will be described. Anomaly detection in the UV-blocking glass, which is the object Sp to be inspected, utilizes the fact that the transmittance of light with a wavelength of 400 nm or less is significantly lower than the transmittance of light with a longer wavelength. FIG. 3 illustrates the wavelength characteristics of the transmittance of the UV-blocking glass. For example, when the wavelength is 400 nm, the transmittance is approximately 30%. When the wavelength is 390 nm, the transmittance is approximately 10%. When the wavelength is 380 nm, the transmittance is approximately 2%. It is desirable that the wavelength of the inspection light is 385 nm or less. When the wavelength is 385 nm, the transmittance is approximately 5%.

[0031] Therefore, when inspection light is irradiated onto the top surface of the object Sp, the inspection light is attenuated on the top surface and inside the object Sp, and the intensity of the inspection light is extremely low by the time it reaches the bottom surface of the object Sp. Because the generation of scattered light on the bottom surface of the object Sp is suppressed, the light that reaches the detector 30 is mainly scattered by foreign matter or irregularities attached to the top surface of the object Sp. Therefore, by facing the coated surface of the object Sp toward the top surface, abnormalities occurring on the coated surface can be detected with little influence from the scattering of inspection light on the non-coated surface. Furthermore, even if the object Sp is placed on a workbench or other support material, the inspection light does not reach the area where the support material and the object Sp come into contact. Therefore, the scattered light generated on the top surface of the object Sp is hardly affected by the support material.

[0032] Next, an example of scattered light detection will be described. FIG. 4 is a diagram showing an example of scattered light detection according to this embodiment. FIG. 4 illustrates a monochrome image obtained by photographing the surface of the inspection object Sp using an industrial digital camera as the detector 30. In the example of FIG. 4, the resolution of the digital camera is 1024 pixels horizontally by 768 pixels vertically. The bit depth for each pixel is 8 bits. That is, the intensity of scattered light is expressed as an integer within the range of 0 to 255 as the brightness value for each pixel. The inspection object Sp was an automobile UV-cut glass with two sticky notes affixed as foreign objects, one on each side. The affixing of these sticky notes corresponds to simulating the occurrence of a known abnormality. The thickness of the glass substrate constituting the UV-cut glass was 3.0 mm, the thickness of the UV-blocking coating was 3 to 4 μm, and the coated surface covered with the UV-blocking coating was the upper surface. However, the output of the light source 20 and the sensitivity of the camera were adjusted so that the detected brightness value would not be saturated within the expected range of the intensity of the scattered light incident on the camera.

[0033] Figures 4(a) and 4(b) show images of a coated surface and an uncoated surface, respectively, taken with inspection light from light source 20 at a wavelength of 385 nm, showing areas with foreign matter attached at different positions. In Figure 4(a), the area with foreign matter attached is significantly brighter than the surrounding area. The average brightness value (hereinafter referred to as the "average brightness value") in the area with foreign matter attached (hereinafter referred to as the "foreign matter attached area") was 200. In contrast, in Figure 4(b), there is almost no difference in brightness between the foreign matter attached area (see dashed line) and its surrounding area. The average brightness value in the foreign matter attached area was 14.

[0034] Figures 4(c) and 4(d) show images of a coated surface and an uncoated surface, respectively, taken using inspection light from light source 20 with a wavelength of 405 nm, showing areas with foreign matter attached at different positions. In Figure 4(c), the area with foreign matter is also brighter than the surrounding area. The average luminance value in the area with foreign matter was 217. In Figure 4(d), there is a slight difference in luminance between the area with foreign matter (see dashed line) and the surrounding area, allowing for a slight visual distinction. The average luminance value in the area with foreign matter was 30.

[0035] Figure 5 shows the luminance ratio for each wavelength of inspection light from the light source 20. The luminance ratio corresponds to the ratio of the average luminance value in the foreign matter-adhered area on the coated surface to the average luminance value in the foreign matter-adhered area on the uncoated surface. When the wavelength was 385 nm, the luminance ratio was 14 times, and when the wavelength was 405 nm, the luminance ratio was 7 times. The shorter the wavelength of the inspection light, the more attenuated it is inside the inspection object Sp, which reduces scattered light from the bottom surface. This proves that the condition of the surface of the inspection object Sp is faithfully reflected in the scattered light, making it possible to accurately detect abnormalities on the surface of the inspection object Sp.

[0036] The detector 30 may be provided with a filter that blocks visible light with wavelengths of 400 nm or longer, and the intensity of scattered light that passes through the filter may be detected. Figure 6 illustrates the spectral characteristics of a visible light cut filter. In the example of Figure 6, the transmittance is less than 0.01 in the wavelength band from 410 nm to 695 nm, and the transmittance increases at shorter and longer wavelengths. The transmittance is maximized at wavelengths of 360 nm and 750 nm, and decreases with shorter wavelengths below 360 nm, and decreases with longer wavelengths above 750 nm. In the wavelength band shorter than 430 nm, wavelength components with low transmittance for the object Sp are blocked, further suppressing scattered light from the bottom surface.

[0037] Figure 7 shows monochrome images obtained by photographing the surface of the specimen Sp using the visible light cut filter shown in Figure 6 placed in front of the objective lens of the digital camera (detector 30). Figures 7(a) and 7(b) show images of the coated surface and the uncoated surface, respectively, photographed using inspection light from light source 20 with a wavelength of 385 nm, in which sticky notes were attached as foreign objects at different positions. Figure 7(a) shows that the area with the foreign object is significantly brighter than the surrounding area. The average luminance value in the area with the foreign object was 213. Figure 7(b) shows that there is almost no difference in luminance between the area with the foreign object and the surrounding area. The average luminance value in the area with the foreign object was 1. Thus, the installation of a visible light cut filter eliminates the effects of scattered light due to anomalies on the uncoated surface.

[0038] The spectral characteristics of the inspection light incident on the UV-blocking coating change before and after passing through the UV-blocking coating. When the coated surface is facing upward, scattered light from anomalies on the coated surface is detected without being affected by the UV-blocking coating. In contrast, the transmitted light that passes through the UV-blocking coating reaches the uncoated surface, and the scattered light from the incident light passes through the UV-blocking coating and reaches the detector 30. Therefore, the scattered light from anomalies on the uncoated surface has a longer wavelength than the scattered light from anomalies on the coated surface. In the example of Figure 8, the transmitted light from the uncoated surface contains a wavelength range of 380 nm to 420 nm as the main component for the inspection light from the light source 20, which contains a wavelength range of 375 nm to 400 nm as the main component.

[0039] Therefore, a filter with a lower transmittance in the wavelength band of the main component of the transmitted light than in the wavelength band of the main component of the scattered light may be installed in the detector 30. Such a filter can be a color filter with a lower transmittance in a specific wavelength band than in other wavelength bands. FIG. 9 shows an example of the spectral characteristics of a color filter. The transmittance of the filter shown in FIG. 9 is 0.01 or greater in the wavelength band from 280 nm to 410 nm and peaks at 355 nm. For wavelengths longer than 355 nm, the transmittance monotonically decreases with increasing wavelength. Therefore, scattered light from an uncoated surface, whose main component is the wavelength band from 380 nm to 420 nm, is attenuated more significantly than scattered light from a coated surface, whose main component is the wavelength band from 375 nm to 400 nm. Therefore, by applying the color filter shown in FIG. 9, the influence of scattered light from an uncoated surface is eliminated, and scattered light from a coated surface can be selectively acquired.

[0040] Examples of foreign matter that may cause abnormalities in UV-blocking glass include dust and dirt. Abnormalities are not limited to the adhesion of foreign matter, but also include scratches, irregularities, and the like. All of these abnormalities scatter incident light and can be detected by the scattered light. The shape of the foreign matter varies depending on the type, and the type and value of the reference size used to determine the abnormal area may vary depending on the shape. For example, for anomalies with an elongated shape, such as dust or scratches, where the longitudinal length is longer than the width, length is used as the type of reference size, with a value of, for example, 1 to 3 mm. For anomalies with a cylindrical shape, such as dust, where the difference between the width and longitudinal length is relatively small, diameter is used as the type of reference size, with a value of, for example, 0.5 to 2 mm.

[0041] Next, an example of an inspection method according to this embodiment will be described below with reference to a flowchart shown in FIG. (Step S102) The measurement control unit 112 causes the light source 20 to irradiate the upper surface of the object under test Sp with inspection light. (Step S104) The measurement control unit 112 causes the detector 30 to detect scattered light generated in the specimen Sp. The determination unit 114 acquires (measures) the intensity distribution of the detected scattered light.

[0042] (Step S106) The determination unit 114 identifies a region where the intensity of scattered light exceeds a reference intensity as a high-intensity region. The determination unit 114 identifies a group of regions where the identified high-intensity regions are spatially continuous as a candidate region. (Step S108) The determination unit 114 determines, from among the identified candidate regions, any candidate region whose size is equal to or larger than a predetermined reference size as an abnormal region. The determination unit 114 determines whether or not an abnormal region exists. If an abnormal region exists (YES in step S108), the process proceeds to step S110. If no abnormal region exists (NO in step S108), the process proceeds to step S112.

[0043] (Step S110) Determination unit 114 determines that there is an abnormality. Thereafter, determination information indicating that there is an abnormality is output to display processing unit 116, a display screen showing the determination information is displayed on display unit 160, and the processing of FIG. 10 ends. (Step S112) The determination unit 114 determines that there is no abnormality. Thereafter, determination information indicating that there is no abnormality is output to the display processing unit 116, and a display screen showing the determination information is displayed on the display unit 160, and the processing of FIG. 10 ends.

[0044] The process of FIG. 10 may be performed independently of or in synchronization with the production process in which the object to be inspected Sp is turned into an intermediate product or a final product.

[0045] 11 is a schematic diagram showing a second configuration example of the inspection system according to this embodiment. As illustrated in FIG. 11, the inspection system S2 may include an inspection device 10, a light source 20, and a detector 30, as well as a conveyor 22 and an inspected object detection unit 23. The conveyor 22 transports the objects to be inspected Sp that are carried out from the previous process toward equipment for the next process. The previous process may include a production process for the objects to be inspected Sp. The objects to be inspected Sp are transported while being supported on the conveyor 22.

[0046] When the specimen Sp is a UV-blocking glass, the pre-processing may include part or all of the UV-blocking glass production process. The UV-blocking glass production process includes a process of covering one surface of a glass substrate with a UV-blocking layer. The process of covering a glass substrate with a UV-blocking layer includes, for example, a process of applying a UV-blocking paint to one surface of the glass substrate and a process of fixing the applied paint. Note that the process of covering a glass substrate with a UV-blocking layer may be, for example, a process of attaching a pre-formed UV-blocking layer (sheet, film) to one surface of the glass substrate, or a process of spraying or adsorbing a UV-blocking paint onto one surface of the glass substrate.

[0047] The inspected object detection unit 23 detects the inspected object Sp transported on the conveyor 22. The inspected object detection unit 23 includes, for example, a light projector 23a and a light receiver 23b, which are installed at positions facing each other across the conveyor 22. The light receiver 23b includes a light receiving element that receives the inspection light projected from the light emitting element of the light projector 23a. When the inspection light is attenuated by the passage of the inspected object Sp, the received light intensity at the light receiver 23b becomes lower than a predetermined intensity threshold. At this time, the light receiver 23b can detect the passing inspected object Sp. When the received light intensity is equal to or higher than the predetermined intensity threshold, the light receiver 23b does not detect the passing inspected object Sp. When the inspected object detection unit 23 detects the inspected object Sp, it outputs an inspected object detection signal indicating the detection of the inspected object Sp to the inspection device 10.

[0048] When an inspected object detection signal is input from the inspected object detection unit 23, the measurement control unit 112 of the inspection device 10 causes the light source 20 to irradiate the inspected object Sp with inspection light and causes the detector 30 to detect scattered light generated on the upper surface of the inspected object Sp. A color filter 32a is installed at the entrance of the detector 30. The color filter 32a has spectral characteristics in which the transmittance is lower in the wavelength band of transmitted light than in the wavelength band of scattered light. Therefore, the detector 30 mainly detects the scattered light component. The determination unit 114 identifies, from the intensity distribution of the scattered light detected by the detector 30, areas where the intensity exceeds a reference intensity as high-intensity areas, and identifies a group of spatially continuous areas of the identified high-intensity areas as candidate areas. Here, the inspection light incident on the test object Sp is attenuated inside the test object Sp. Because almost no incident inspection light reaches the bottom surface of the test object Sp, reflection of the inspection light at the area of ​​the surface of the conveyor 22 that is in contact with the test object Sp is suppressed or prevented. Therefore, the detector 30 can detect scattered light generated on the top surface of the test object Sp with almost no influence from the conveyor 22. The determination unit 114 determines whether or not an abnormality exists based on whether or not the identified candidate area has an abnormal area whose size is equal to or larger than a predetermined reference size. The determination unit 114 may notify the equipment of a downstream process of determination information indicating the determination result.

[0049] The post-process may include a step of determining whether or not to discard the UV-blocking glass, which is the test object Sp, based on the presence or absence of an abnormality as a result of the determination. The discarded UV-blocking glass may be melted and used to produce a new glass substrate. The remaining UV-blocking glass that is not discarded is sorted and shipped.

[0050] The inspection system S2 may be realized as part of a production system for UV-blocking glass. This production system produces UV-blocking glass by applying an ultraviolet-blocking paint to the upper surface of a glass substrate. In other words, this production system performs a production method for UV-blocking glass, including the steps of applying the UV-blocking paint to the glass substrate, forming an object to be inspected Sp by fixing a layer of the UV-blocking paint on the glass substrate, and determining whether or not there is an abnormality in the object to be inspected Sp, as illustrated in FIG. 10 .

[0051] As described above, the inspection systems S1 and S2 according to this embodiment include a light source 20 that irradiates the first surface, which is one of the surfaces of the inspection object Sp including glass, with inspection light, a detector 30 that detects the intensity of scattered light generated on the first surface, and a determination unit 114 that determines the presence or absence of an abnormality on the surface of the inspection object Sp based on the intensity of the scattered light. The inspection light includes components of wavelengths (e.g., 400 nm or less) whose transmittance through the inspection object Sp is lower than a predetermined reference transmittance. The first surface may be a coated surface of a glass substrate covered with an ultraviolet ray transmission preventing layer. This embodiment may be realized as an inspection device 10 that includes a light source 20 that irradiates inspection light onto a first surface, which is one of the surfaces of the object to be inspected, a detector 30 that detects the intensity of scattered light generated on the first surface, and a judgment unit 114 that judges whether or not there is an abnormality on the first surface based on the detected intensity, and the inspection light includes wavelength components whose transmittance through the object to be inspected Sp is lower than a predetermined reference transmittance. This embodiment may be realized as a method for producing UV-blocking glass, which includes steps of covering a glass substrate with an UV-blocking layer (e.g., applying a UV-blocking paint) to produce an object to be inspected Sp, irradiating the surface of the object to be inspected Sp with inspection light, and determining whether or not there is an abnormality on the first surface.

[0052] With this configuration, the inspection light incident on the first surface is attenuated before reaching the second surface, which is the other surface of the inspection object Sp, so that the scattered light caused by an abnormality on the second surface is weaker than the scattered light caused on the first surface. Since the influence of the scattered light caused on the second surface is suppressed, the abnormality on the first surface can be accurately detected.

[0053] Furthermore, the detector 30 may be installed facing an irradiation area, which is an area where the inspection light is irradiated onto the first surface, in a direction different from the reflection direction in which the reflected light is generated from the irradiation area. According to this configuration, scattered light, but not reflected light, generated in the irradiation area is incident on detector 30. Since the influence of reflected light is suppressed, abnormalities on the first surface can be detected accurately.

[0054] In addition, the judgment unit 114 may judge an abnormality to exist when there is a region (e.g., a candidate region) where the intensity of the scattered light detected by the detector 30 exceeds a predetermined reference intensity and a region (e.g., an abnormal region) whose size is equal to or greater than a predetermined reference value. According to this configuration, an abnormality is detected on the first surface when the intensity of scattered light exceeds the reference intensity and the surface has an abnormal area with a size equal to or larger than the reference value. Detecting large abnormal areas that pose quality issues contributes to quality control of the specimen Sp.

[0055] Furthermore, the detector 30 may be an imaging device (for example, a camera) that is capable of detecting wavelength components whose transmittance of the object under test is lower than a predetermined reference transmittance and that has a plurality of light receiving elements arranged two-dimensionally. According to this configuration, an imaging device having a plurality of light receiving elements arranged two-dimensionally is used as the detector 30, so that the inspection system S1 can be realized economically.

[0056] The detector 30 may be provided with a filter that blocks wavelength components (for example, 400 nm or more) at which the transmittance of the object under test Sp is equal to or greater than a predetermined reference transmittance. With this configuration, wavelength components of the scattered light generated on the first surface, at which the transmittance of the inspection object Sp is less than a predetermined reference transmittance, are blocked, thereby suppressing wavelength components of the scattered light generated on the second surface by the inspection light that has passed through the inspection object Sp. By further reducing the influence of the scattered light generated on the second surface, abnormalities on the first surface can be detected more accurately.

[0057] The first surface is covered with an ultraviolet ray-blocking layer (i.e., an ultraviolet ray-blocking coating), and the second surface, which is the other surface of the object Sp, is not covered with an ultraviolet ray-blocking layer, and the transmittance of the filter in the wavelength band of scattered light generated on the second surface may be lower than the transmittance of the filter in the wavelength band of the inspection light. With this configuration, the spectral characteristics of the inspection light change as it passes through the UV-ray transmission preventing layer, which further suppresses the scattered light that becomes apparent on the second surface when the inspection light passes through the filter. By further reducing the effect of scattered light that occurs on the second surface, abnormalities on the first surface can be detected more accurately.

[0058] The above has described in detail an embodiment of the present invention with reference to the drawings, but the specific configuration is not limited to that described above, and various design modifications can be made within the scope that does not deviate from the gist of the present invention.

[0059] For example, the inspection apparatus 10 may be implemented as part of a production facility that produces the object Sp as an intermediate product or a final product, or may be a separate device separate from the inspection system S1. The object Sp is not limited to UV-resistant transparent glass, and may be an object primarily made of glass. Such an object may be, for example, a glass sheet or functional glass such as insulating glass. The inspection device 10 may include an operation unit 150 and a display unit 160, or may omit some or all of them. The operation unit 150 and the display unit 160 may be connected to each other via the input / output unit 140 in a wired or wireless manner. In the inspection device 10, the measurement control unit 112 and the display processing unit 116 may be omitted in part or in whole.

[0060] Furthermore, part or all of the inspection device 10 in the above-described embodiment may be realized as an integrated circuit such as an LSI (Large Scale Integration). Each functional block of the inspection device 10 may be individually implemented as a processor, or part or all of the functional blocks may be integrated into a processor. Furthermore, the integrated circuit implementation method is not limited to LSI, and may be implemented using a dedicated circuit or a general-purpose processor. Furthermore, if an integrated circuit implementation technology that can replace LSI emerges due to advances in semiconductor technology, an integrated circuit based on that technology may be used. [Explanation of symbols]

[0061] S1, S2... inspection system, 10... inspection device, 20... light source, 22... conveyor, 23... inspection object detection unit, 23a... light projector, 23b... light receiver, 30... detector, 110... control unit, 112... measurement control unit, 114... judgment unit, 116... display processing unit, 140... input / output unit, 150... operation unit, 160... display unit, 170... memory unit, Sp... inspection object, CS... coated surface, NS... non-coated surface

Claims

1. a light source that irradiates inspection light onto a first surface, which is one of the surfaces of the object to be inspected, including glass; a detector for detecting the intensity of scattered light generated at the first surface; a determination unit that determines whether or not there is an abnormality on the first surface based on the intensity, The inspection light includes a wavelength component whose transmittance of the inspection object is lower than a predetermined reference transmittance. Inspection system.

2. The detector comprises: The inspection light is directed to an illumination area on the first surface, and the illumination light is directed in a direction different from the direction of reflection of the reflected light from the illumination area. The inspection system of claim 1 .

3. The determination unit When the intensity exceeds a predetermined reference intensity and the size of the region is equal to or greater than a predetermined reference value, the region is determined to be abnormal. The inspection system of claim 1 .

4. The detector is an imaging device that can detect the wavelength component and has a plurality of light receiving elements that are arranged two-dimensionally. The inspection system of claim 1 .

5. A filter that blocks wavelength components at which the transmittance of the object under test is equal to or greater than the reference transmittance is installed in the detector. The inspection system of claim 1 .

6. the first surface is covered with an ultraviolet light transmission preventing layer, a second surface, which is the other surface of the object to be inspected, is not covered with the ultraviolet ray transmission preventing layer; The transmittance of the filter in the wavelength band of the scattered light generated on the second surface is lower than the transmittance of the filter in the wavelength band of the inspection light. The inspection system of claim 5 .

7. causing the light source to irradiate a first surface, which is one of the surfaces of the object under inspection, with inspection light; causing a detector to detect the intensity of scattered light occurring at said first surface; a determination unit that determines whether or not there is an abnormality on the first surface based on the intensity, The inspection light includes a wavelength component whose transmittance of the inspection object is lower than a predetermined reference transmittance. Inspection equipment.

8. An inspection method in an inspection system, comprising: Irradiating inspection light from a light source onto a first surface, which is one of the surfaces of the object under inspection; The detector detects the intensity of the scattered light generated at the first surface; The determination unit determines whether there is an abnormality on the first surface based on the intensity, and The inspection light includes a wavelength component whose transmittance of the inspection object is lower than a predetermined reference transmittance. Testing method.

9. a step of covering a glass substrate with an ultraviolet light transmission preventing layer to produce the test object; Execute the inspection method according to claim 8. A method for producing UV-blocking glass.

Images