Glass plate inspection method and glass plate inspection system

Abstract

The purpose of the present invention is to provide a glass plate inspection method and a glass plate inspection system that make it possible to efficiently and easily inspect the surfaces of a glass plate. This glass plate inspection method for inspecting a glass plate for flaws is characterized in that: a refractive material having an inclined surface is arranged in contact with one surface of the glass plate; the inclined surface is set at an angle (90°-θ) from the surface of the glass plate; the length of an oblique side of the inclined surface is longer than 2tSinθ where the thickness of the glass plate is t; light is made incident on the inclined surface; the light is incident on the glass plate through the refractive material; and the light undergoes total internal reflection at the boundary between one surface and another surface of the glass plate.

Description

Glass plate inspection method and glass plate inspection system

[0001] The present invention relates to a glass plate inspection method and a glass plate inspection system.

[0002] Since solar panels are installed outdoors, there is a possibility that the glass surface of the panels may have numerous scratches during use. During preventive maintenance after installation, an inspection method is required to determine whether the panels can be reused.

[0003] Patent Document 1 discloses a technique for inspecting the edge of a glass substrate, in which light is incident on the glass substrate through a refractive body (prism) and travels through the glass substrate by total reflection until it reaches the edge of the glass substrate. In this way, the light reaches the edge of the glass substrate with almost no attenuation, making it possible to brightly observe scattered light caused by microcracks at the edge of the glass substrate (see paragraph

[0028] and [Figure 1b]).

[0004] JP 2011-043457 A

[0005] However, in Patent Document 1, the shape of the refractive body, the observation range, etc. are not taken into consideration, and it is desired to efficiently observe the surface of the glass plate.

[0006] In particular, the presence or absence of microcracks, which are tiny scratches on glass plates, is an important inspection item for quality assurance of strength and durability. However, in the case of used products, this inspection requires polishing the edges, which increases the inspection cost.

[0007] An object of the present invention is to provide a glass plate inspection method and a glass plate inspection system that can inspect the surface of a glass plate efficiently and easily.

[0008] A glass plate inspection method of the present invention is a glass plate inspection method for inspecting a glass plate for scratches, characterized in that a refractive material having an inclined surface is placed in contact with one surface of the glass plate, the inclined surface forms an angle of (90 degrees - θ) with the surface of the glass plate, the length of the hypotenuse of the inclined surface is longer than 2t sin θ when the thickness of the glass plate is t, and light is incident on the inclined surface, passes through the refractive material, and enters the glass plate, where the light is totally reflected by one surface and the other surface of the glass plate.

[0009] Furthermore, the glass plate inspection system of the present invention is a glass plate inspection system for inspecting a glass plate for scratches, characterized in that it includes a refractive material arranged in contact with one side of the glass plate and having an inclined surface, the inclined surface forms an angle of (90 degrees - θ) with the surface of the glass plate, the length of the hypotenuse of the inclined surface is longer than 2t Sinθ when the thickness of the glass plate is t, and light is incident on the inclined surface, passes through the refractive material, and enters the glass plate, where it is totally reflected by one side and the other side of the glass plate.

[0010] According to the present invention, it is possible to provide a glass plate inspection method and a glass plate inspection system that can inspect the surface of a glass plate efficiently and simply.

[0011] Problems, configurations, and effects other than those described above will become apparent from the following description of the preferred embodiments of the invention.

[0012] Fig. 1 is a schematic diagram showing a method for inspecting a glass plate for micro scratches according to the present embodiment. Fig. 2 is a schematic diagram showing the principle of inspection of a glass plate for micro scratches according to the present embodiment. Fig. 3 is a diagram showing an example of a refractive material for inspection of a glass plate for micro scratches according to the present embodiment. Fig. 4 is a diagram showing an example of a method for inspecting a glass plate for micro scratches according to the present embodiment. Fig. 5 is a diagram showing a system for inspecting a glass plate for micro scratches according to the present embodiment.

[0013] In the following, detailed explanations of the embodiments of the present invention will be given using a solar panel as an example. The amount of solar panels discarded can increase rapidly as usage increases and the panels age, making recycling and reuse important for reducing environmental impact. Reusing the glass on the surface of solar panels is particularly desirable because it is a valuable material with a high waste volume. Solar panels installed outdoors may have scratches on their surfaces due to wind and rain, and fine scratches such as microcracks can develop into larger cracks. Therefore, a method for detecting fine scratches is needed to control the quality of reused products.

[0014] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The examples are illustrative of the present invention, and for clarity of explanation, appropriate omissions and simplifications have been made. The present invention can be implemented in various other forms. Unless otherwise specified, each component may be singular or plural.

[0015] Furthermore, in order to facilitate understanding of the invention, the position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc. Therefore, the present invention is not necessarily limited to the position, size, shape, range, etc. disclosed in the drawings.

[0016] FIG. 1 is a schematic diagram illustrating a method for inspecting glass plates for micro-flaws according to this embodiment. In this embodiment, a refractive element 1, such as a prism, having an inclined surface and capable of refracting light is disposed at one end of a glass plate 2 on one surface thereof. Light is incident on the refractive element 1 from a light source 3 at an oblique angle. The light is then incident on the inclined surface of the refractive element 1. This light propagates in the longitudinal direction of the glass plate 2 while repeatedly reflecting within the glass plate 2. In other words, the light travels through the glass plate 2 after being totally reflected by one surface and then the other surface until it reaches the other end of the glass plate 2. In other words, if there is a scratch on one surface of the glass plate 2, the brightness of the light from inside the glass plate 2 will differ, allowing the scratch to be detected. Here, the direction from one end of the glass plate 2 to the other, i.e., the direction in which light propagates while reflecting within the glass plate 2, is referred to as the longitudinal direction.

[0017] The inclined surface of the refractive material 1 forms an angle of (90 degrees - θ) with the surface of the glass plate 2, and the length of the hypotenuse of the inclined surface is configured to be longer than 2t sin θ, where t is the thickness of the glass plate 2. This allows light of the desired width to be incident. By allowing light to be incident at the desired width, the surface of the glass plate 2 can be efficiently inspected. If the width is narrow, for example, a gap will be created on one surface between the light reflected the first time and the light reflected the second time, and since no light is reflected in that gap, it will be difficult to detect scratches. In this embodiment, the length of the hypotenuse of the inclined surface is configured to be longer than 2t sin θ, where t is the thickness of the glass plate 2, allowing light of the desired width to be incident.

[0018] As described above, the light reaches the other end of the glass plate 2 with almost no attenuation, so that the scattered light due to the microcracks on the surface of the glass plate 2 can be brightly observed.

[0019] Furthermore, when the thickness of the glass plate 2 is t, the glass plate 2 is configured to be longer than 2t sinθ, and the width of the incident light in the length direction of the hypotenuse is longer than 2t sinθ. This allows for efficient inspection without gaps in the longitudinal direction of the glass plate 2. Here, the direction along the hypotenuse of the refractive material 1 in the figure is referred to as the length direction of the hypotenuse, and the depth direction of the hypotenuse is referred to as the thickness direction of the slope. Note that light scattering occurs on one surface of the glass plate 2, making it possible to visually check for minute scratches, etc. Furthermore, the use of the refractive material 1 allows for inspection without the need for light to be incident from the edge of the glass plate 2. In other words, if light is to be incident from the edge, the edge must be processed, but by using the refractive material 1, this does not require processing of the edge, thereby reducing the process and cost.

[0020] 1, a light detection unit 4 is provided that detects the luminance distribution, which is the state of one surface of the glass plate 2. This light detection unit 4 makes it possible to accurately determine the presence or absence of minute scratches and their state.

[0021] It is desirable that the contact surface 5 between the glass plate 2 and the refractive material 1 be in close contact. For example, a gel or liquid may be provided on this contact surface to fill the air gap at the contact surface 5. By filling the air gap at the contact surface 5 with gel or liquid, light can be propagated with high precision.

[0022] Figure 2 is a schematic diagram showing the principle of the microdamage inspection of the glass plate according to this embodiment. Here, n0 is the refractive index of air, n1 is the refractive index of the glass plate, and n2 is the refractive index of the refractive material 1. As shown in the figure, the refractive material 1 is arranged on the surface of the glass plate 2, and light is incident on the inclined surface of the refractive material 1 at an angle of θ2 with respect to the plane perpendicular to the surface of the glass plate 2. The incident light passes through the refractive material 1 and enters the glass plate 2, and at an angle of θ1 with respect to the plane perpendicular to the surface of the glass plate 2, total reflection occurs on the other surface, and total reflection of light occurs on one surface and the other surface of the glass plate 2. That is, the range satisfies n0 / n2 < Sinθ < n1 / n2, and the refractive index difference |n2 - n1| between the refractive material 1 and the glass plate 2 is less than 0.1. Therefore, the transmitted light 10 is eliminated, and the reflected light 11 is configured to be totally reflected.

[0023] Figure 3 is a diagram showing an example of the refractive material for the microdamage inspection of the glass plate according to this embodiment. The refractive material 1 and the light source 3 are integrated, and the loss due to reflection at the interface between the air and the refractive material 1 between the light source 3 and the refractive material 1 can be reduced. Also, the equipment can be miniaturized.

[0024] Figure 4 is a diagram showing an example of the microdamage inspection method of the glass plate according to this embodiment. In this embodiment, the refractive material 1 is arranged at one end of the glass plate 2, and the surface of the glass plate 2 is inspected. At this time, the contact surface between the glass plate 2 and the refractive material 1 cannot be inspected. Next, the refractive material 1 is arranged at the other end of the glass plate 2, and the surface of the glass plate 2 is inspected. By inspecting in this way, a comprehensive inspection is possible.

[0025] Figure 5 is a diagram showing an example of the microdamage inspection method of the glass plate according to this embodiment. Depending on the glass plate 2, it may also be considered to focus on inspecting its end portion. This is possible by installing the refractive material 1 having a trapezoidal shape that is symmetric about the center on the glass plate 2. By incident light on each inclined surface of the trapezoid, key inspections of the end portions of the glass plate can be performed. Also, damage progressing from the end portion can be confirmed in a single inspection.

[0026] FIG. 6 is a diagram showing a glass plate micro-flaw inspection system according to the present embodiment. As in the first embodiment, the system includes a light source 3, a refractive material 1, and a light detection unit 4. The light detection unit 4 obtains the luminance distribution of light. This luminance distribution information 6 is transmitted to a diagnosis unit 7. The diagnosis unit 7 analyzes information such as the number (density), size, and position of scratches, and diagnoses the lifespan and load-bearing capacity until the scratches develop into larger cracks. For example, it is possible to determine at least one of the number, density, and depth of scratches, calculate the service life or load-bearing capacity, and output a quality evaluation of the glass plate 2 as a diagnosis result 8.

[0027] In this embodiment, the diagnostic unit 7 executes a program to perform processing (analysis and diagnosis). Here, the calculation means in the diagnostic unit 7 executes the program using a processor (e.g., a CPU or a GPU) and performs processing defined by the program while using storage resources (e.g., a memory) and interface devices (e.g., a communication port). Therefore, the entity that executes the program and performs the processing may be the processor. Similarly, the entity that executes the program and performs the processing may be a controller, device, system, computer, or node that has a processor. The entity that executes the program and performs the processing may be any calculation unit, and may include a dedicated circuit that performs specific processing.

[0028] By applying this embodiment to the inspection of minute scratches on the glass plates of solar panels, the recycling efficiency of solar panels can be improved, which will also lead to increased customer value such as social contribution and CO2 reduction.

[0029] The present invention can also be applied to quality assurance of second-hand glass sheets and inspection of window glass in high-rise buildings, railway vehicles, airplanes, automobiles, etc., making it possible to easily inspect glass sheets for minute scratches and confirm their quality.

[0030] REFERENCE SIGNS LIST 1... refractive material 2... glass plate 3... light source 4... light detection unit 5... contact surface 6... luminance distribution information 7... diagnosis unit 8... diagnosis result 10... transmitted light 11... reflected light

Claims

1. In a method for inspecting a glass plate for scratches, a refractive material having an inclined surface is disposed in contact with one surface of the glass plate, the angle formed by the inclined surface and the surface of the glass plate is (90 degrees - θ), and the length of the hypotenuse of the inclined surface is longer than 2tSinθ when the thickness of the glass plate is t. Light is incident on the inclined surface, the light is incident on the glass plate through the refractive material, and total reflection occurs on one surface and the other surface of the glass plate. A method for inspecting a glass plate, characterized by the above.

2. In the method for inspecting a glass plate according to claim 1, the width of the light in the direction of the hypotenuse length incident on the inclined surface is made longer than 2tSinθ. A method for inspecting a glass plate, characterized by the above.

3. In the method for inspecting a glass plate according to claim 1, when the refractive index of the space where the glass plate is installed is n0, the refractive index of the glass plate is n1, and the refractive index of the refractive material is n2, the range satisfies n0 / n2 < Sinθ < n1 / n2, and the refractive index difference |n2 - n1| between the refractive material and the glass plate is less than 0.

1. A method for inspecting a glass plate, characterized by the above.

4. In the method for inspecting a glass plate according to claim 1, a gel or a liquid is applied to the surface of the refractive material that contacts the glass plate. A method for inspecting a glass plate, characterized by the above.

5. In the method for inspecting a glass plate according to claim 1, a light source is installed on the inclined surface of the refractive material. A method for inspecting a glass plate, characterized by the above.

6. In the method for inspecting a glass plate according to claim 1, the refractive material is installed at one end of the glass plate, light is incident to inspect the glass plate, the refractive material is installed at the other end of the glass plate, and light is incident to inspect the glass plate. A method for inspecting a glass plate, characterized by the above.

7. In the method for inspecting a glass plate according to claim 1, a trapezoidal refractive material having two inclined surfaces is installed at the center of the glass plate, and light is incident to inspect the glass plate. A method for inspecting a glass plate, characterized by the above.

8. A glass plate inspection system for inspecting scratches on glass plates, comprising a refractive material having an inclined surface, arranged in contact with one surface of the glass plate, the inclined surface forming an angle of (90 degrees - θ) with the surface of the glass plate, the length of the hypotenuse of the inclined surface being longer than 2t Sinθ, where t is the thickness of the glass plate, and wherein light is incident on the inclined surface, passes through the refractive material and enters the glass plate, and is totally reflected by one surface and the other surface of the glass plate.

9. A glass plate inspection system according to claim 8, wherein the width of the light incident on the inclined surface in the length direction of the oblique side is configured to be longer than 2t Sin θ.

10. A glass plate inspection system according to claim 8, further comprising a light detection unit for detecting light from the surface of the glass plate.

11. A glass plate inspection system according to claim 8, comprising: a light detection unit that detects light from the surface of the glass plate; and a diagnostic unit that evaluates the quality of the glass plate based on information detected by the light detection unit.

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