JP2006349599A - Device and method for inspecting transparent substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent erroneous detection of a flaw in a transparent substrate as a defect of a pattern. <P>SOLUTION: The transparent substrate inspection device 100 for defect-inspecting the transparent substrate 2 having the pattern 4 formed on a plate surface comprises: a lighting system 1 emitting illuminating light to the transparent substrate 2; and an imaging device 3 arranged on the opposite side to the lighting system 1 across the transparent substrate 2. The device further comprises a defect detector 8 detecting defects of the transparent substrate 2 in a state in which at least one side of the transparent substrate 2 is dipped in a liquid 5 having a refractive index close to that of the transparent substrate 2. The pattern 4 on the plate surface has non-transmitting property relative to the illuminating light, and defects of the transparent substrate 2 are detected based on an image taken by the imaging device 3. According to this, if the transparent substrate 2 has a flaw 7, refraction on the interface between the flaw 7 and the transparent substrate 2 is eliminated to prevent erroneous detection of the flaw 7 as a defect of the pattern 4. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a transparent substrate inspection apparatus, a transparent substrate inspection method, and a flat display panel having a transparent substrate inspected by the inspection method.

  2. Description of the Related Art Conventionally, for example, flat display panels such as a plasma display panel (PDP) and a liquid crystal display (LCD) are known.

  A flat display panel generally includes a pair of transparent substrates made of a glass substrate or other transparent material. That is, the flat display panel includes, for example, a front transparent substrate and a rear transparent substrate arranged so as to face each other, and a display cell is provided between the two substrates.

  By the way, electrodes or other components are formed in a pattern on the plate surface of the transparent substrate of the flat display panel.

  Conventionally, there is a technique for inspecting such a transparent substrate for defects.

  FIG. 1 is a schematic front view showing a conventional transparent substrate inspection apparatus 1000 that inspects a pattern on a plate surface of a transparent substrate.

  As shown in FIG. 1, a conventional transparent substrate inspection apparatus 1000 includes an illumination device 1001 disposed below a horizontally disposed transparent substrate 1002, and the illumination device 1001 opposite to the transparent substrate 1002. That is, the image pickup apparatus 1003 disposed above the transparent substrate 1002 is provided. A fine pattern 1004 is formed on the surface of the transparent substrate 1002.

  According to such a conventional transparent substrate inspection apparatus 1000, the imaging apparatus 1003 illuminates the glass substrate 1002 with the illumination apparatus 1001, and irradiates the imaging apparatus 1003 side with transmitted light that passes through the transparent substrate 1002. A defect of the glass substrate 1002 can be detected by acquiring an image of the glass substrate 1002 and analyzing the image.

  The detected defect is a defect of the pattern 1004 formed on the transparent substrate 1002 or a foreign matter / dirt on the glass substrate 1002. Further, examples of the detected defect of the pattern 1004 include chipping, disconnection, protrusion, and short circuit of the pattern 1004.

  As prior art documents related to the present invention, for example, there are Patent Documents 1 and 2.

  Among them, the technique disclosed in Patent Document 1 is such that when a pattern is formed on a substrate via an adhesive layer, an illumination unit and an imaging unit are arranged so as to face each other through the substrate, and a pattern inspection is performed. In the technology for performing the above, a liquid is applied to the surface of the adhesive layer in order to prevent erroneous detection of irregularities on the surface of the adhesive layer on the substrate as a pattern defect (overdetection in Patent Document 1). Is.

  More specifically, the technique of Patent Document 1 is for inspecting a pattern defect in a TAB tape, and once the TAB tape fed from the tape reel is passed through a liquid (alcohol), the adhesive layer is formed. After applying the liquid to the surface, the pattern is inspected in the atmosphere, and the TAB tape after the inspection is wound up and collected on a take-up reel.

  Further, the technique of Patent Document 2 is a technique for inspecting defects inside a transparent body such as glass, and a transparent laser beam with a narrow irradiation range is transparent with the transparent body buried in a liquid having a refractive index close to that. The body is scanned while being irradiated, and the scattered light is observed visually.

More specifically, in the technique of Patent Document 2, as shown in FIG. 2 of the document, when a substrate-like transparent body is to be inspected, a laser beam is irradiated in a direction intersecting the plate surface. Instead, the laser beam is irradiated in parallel to the plate surface direction.
JP 2004-361329 A JP-A-1-250846

  However, in the related art shown in FIG. 1, for example, when a scratch 1005 exists on the back surface of the transparent substrate 1002, the scratch 1005 may be erroneously detected as a defect of the pattern 1004.

  This is because the light that enters the glass substrate 1002 from the scratch 1005 portion in the atmosphere is refracted differently from the light that enters the glass substrate 1002 from the portion without the scratch 1005, so the image acquired by the imaging device 1002 This is because the luminance gradation of the portion corresponding to the scratch 1005 is lower than that of the portion without the scratch 1005. Similarly, when a scratch (not shown) exists on the surface of the transparent substrate 1002, this scratch may be erroneously detected as a defect of the pattern 1004.

  The problem to be solved by the present invention includes the above-described problem as an example.

  In the technique of Patent Document 1, when the pattern is formed on the substrate via the adhesive layer, the liquid is applied to the surface of the adhesive layer. In some cases, this scratch is erroneously detected as a pattern defect.

  That is, the technique of Patent Document 1 cannot solve the above problem.

  Furthermore, in the technique of Patent Document 1, the TAB tape delivered from the tape reel is once passed through the liquid and the liquid is applied to the surface of the adhesive layer, and then the pattern is inspected in the atmosphere. Since the subsequent TAB tape is taken up and collected on the take-up reel, it cannot be resumed after a series of operations of TAB tape delivery, liquid application, pattern inspection, and TAB tape take-up collection are interrupted. There is a problem. This is because if the operation is interrupted, the liquid on the surface of the adhesive layer is dried and a suitable inspection cannot be performed.

  Moreover, the technique of patent document 2 is for detecting the defect inside a transparent body, and is completely different from the technique which prevents detecting the damage | wound formed in the board surface of a board | substrate accidentally.

  Furthermore, in the technique of Patent Document 2, as shown in FIG. 2, when a substrate-type transparent body is to be inspected, the plate is not irradiated with a laser beam in a direction crossing the plate surface. A laser beam is irradiated parallel to the surface direction. Therefore, since the laser beam does not pass through the plate surface of the substrate, it is impossible to inspect the shape of the pattern formed on the plate surface (front surface or back surface) in the first place.

  Moreover, when the technique of patent document 2 has a defect in a part of transparent body, it has the structure which can recognize visually the remarkable scattered light from the defective part easily visually. That is, in the technique of Patent Document 2, since defects are determined by visually observing irregular reflections, it is impossible to detect defects with fine patterns in the first place.

  From the above, Patent Documents 1 and 2 cannot solve the above problem.

  The invention described in claim 1 is a transparent substrate inspection apparatus for inspecting a defect of a transparent substrate having a pattern formed on a plate surface, an illuminating device that irradiates the transparent substrate with illumination light, and the illuminating device. Is an imaging device disposed on the opposite side across the transparent substrate, and at least one surface of the transparent substrate is immersed in a liquid having a refractive index similar to that of the transparent substrate, and the plate surface direction of the transparent substrate is determined from the illumination device. And a defect detection device that detects a defect of the transparent substrate in a state intersecting with the traveling direction of the irradiation light of, and the pattern on the plate surface is impermeable to the illumination light And detecting a defect of the transparent substrate based on an image picked up by the image pickup device.

  The invention according to claim 10 is a method for inspecting a defect in a transparent substrate having a pattern formed on a plate surface, wherein at least one surface of the transparent substrate is immersed in a liquid having a refractive index approximate to that of the transparent substrate. And a process of irradiating the transparent substrate with an illuminating device in a state where the plate surface direction of the transparent substrate intersects the traveling direction of the irradiation light from the illuminating device, and the illuminating device with the transparent substrate interposed therebetween Is a process of imaging the transparent substrate by an imaging device arranged on the opposite side, and an image obtained by imaging the pattern on the substrate that is impermeable to the illumination light by the imaging device And detecting a defect of the transparent substrate in comparison with a pattern stored in the defect detection device.

  A flat display panel according to an eleventh aspect includes the transparent substrate that has been inspected for defects by the transparent substrate inspection method according to the tenth aspect.

  Next, an embodiment will be described.

  The transparent substrate inspection apparatus according to the present embodiment irradiates the transparent substrate with light in the transparent substrate inspection apparatus for inspecting a defect of the transparent substrate in which a pattern is formed on a plate surface (front surface or back surface). An illuminating device, an imaging device disposed on the opposite side of the illuminating device, and at least one surface of the transparent substrate is immersed in a liquid having a refractive index similar to that of the transparent substrate, A defect detection device that detects a defect of the transparent substrate in a state in which the plate surface direction intersects the traveling direction of the irradiation light from the illumination device, and the pattern on the plate surface corresponds to the illumination light On the other hand, it has non-transparency, and it is characterized by detecting a defect of the transparent substrate based on an image picked up by the image pickup device.

  According to the transparent substrate inspection apparatus according to the present embodiment, at least one surface of the transparent substrate is immersed in a liquid having a refractive index approximate to that of the transparent substrate, and the plate surface direction of the transparent substrate is set to the irradiation light from the illumination device. A defect detection device that detects a defect of the transparent substrate in a state intersecting with the traveling direction, and the pattern on the plate surface is impermeable to the illumination light, Since the defect of the transparent substrate is detected based on the image picked up by the image pickup device, if there is a scratch on the plate surface of the glass substrate or other transparent substrate, the scratch is erroneously detected as a pattern defect. It can be prevented or suppressed. Because the refractive indexes of the transparent substrate and the liquid are close to each other, the refraction of light when passing through the interface between the transparent substrate and the liquid can be prevented or suppressed. This is because it is possible to prevent a difference in luminance gradation between a portion to be processed and a portion having no scratch. In this way, by preventing or suppressing the detection of scratches on the transparent substrate as pattern defects, it is possible to accurately detect only defects to be detected, such as pattern defects and foreign matter / dirt on the transparent substrate. Therefore, the reliability of pattern inspection is improved. The detected pattern defect is, for example, a chipped pattern, disconnection, protrusion, or short circuit.

  Further, since at least one surface of the transparent substrate is imaged by the imaging device while being immersed in a liquid having a refractive index similar to that of the transparent substrate, the surface of the transparent substrate immersed in the liquid is not dried. Therefore, a series of inspection operations can be arbitrarily interrupted and restarted.

  Further, the transparent substrate processing step includes, for example, wet processing such as cleaning processing. By incorporating the transparent substrate inspection apparatus according to the present embodiment into wet equipment for performing such wet processing, the space of the equipment can be saved. In addition, when a defect is detected, quick feedback to the previous process becomes possible. In the cleaning process after pattern formation on the transparent substrate, for example, pure water is used. However, since the refractive index of water is close to the refractive index of a transparent substrate such as a glass substrate, the cleaning processing apparatus according to this embodiment is used. By incorporating such a transparent substrate inspection device, it is possible to inspect defects as described above.

  In the transparent substrate inspection apparatus according to the present embodiment, the defect detection apparatus includes a pattern storage unit that stores a pattern on the plate surface, an image acquired by the imaging device, and a pattern stored in the pattern storage unit. It is an example that preferably includes a comparison / determination unit that determines whether or not there is a defect. Thus, it is possible to suitably detect a defect in the substrate.

  In the transparent substrate inspection apparatus according to the present embodiment, it is a preferable example that the imaging by the imaging apparatus is performed in a state where the entire surface of the transparent substrate is immersed in the liquid. Even if there is a flaw on either the front side or the back side, it is possible to prevent or suppress erroneous detection of this flaw.

  In this case, the apparatus further comprises: a liquid container storing the liquid; and a transport mechanism that transports the transparent substrate in a state where the entire surface of the transparent substrate is immersed in the liquid in the liquid container. A preferred example is a structure in which an opening that allows the light from the illumination device to irradiate the transparent substrate is formed in a portion located between the illumination device and the imaging device. In this case, since the illumination by the illumination device and the imaging by the imaging device are performed while the transparent substrate is conveyed by the conveyance mechanism, the scale of the illumination device and the imaging device can be reduced, and the cost can be reduced. In addition, since an opening is formed in a portion of the transport mechanism located between the illumination device and the imaging device, the transport mechanism does not hinder inspection.

  Alternatively, in the transparent substrate inspection apparatus according to the present embodiment, it is also preferable that the imaging apparatus performs the imaging with only one surface of the transparent substrate immersed in the liquid, thereby reducing the amount of liquid. It is possible to inspect defects as described above by quantity.

  In this case, the apparatus further comprises: a liquid container storing the liquid; and a transport mechanism that transports the transparent substrate with the lower surface of the transparent substrate immersed in the liquid in the liquid container. A preferred example is a structure in which an opening that allows the light from the illumination device to irradiate the transparent substrate is formed in a portion located between the illumination device and the imaging device. Also in this case, since the imaging device performs imaging while transporting the transparent substrate by the transport mechanism, the scale of the imaging device can be reduced, and the cost can be reduced. In addition, since an opening is formed in a portion of the transport mechanism located between the illumination device and the imaging device, the transport mechanism does not hinder inspection.

  In the transparent substrate inspection apparatus according to the present embodiment, the transport mechanism is preferably configured to include, for example, a plurality of rollers that transport the transparent substrate, and thereby transport the transparent substrate suitably. Is possible.

  The transparent substrate inspection apparatus according to the present embodiment further includes a liquid container having an upper end opened and storing the liquid until the upper end is reached, and the transparent substrate is placed on the upper end opening of the liquid container. It is also preferable that the imaging device performs the imaging with the lower surface of the transparent substrate immersed in the liquid. In this case, there is an advantage that handling of the transparent substrate is facilitated as compared with the case where the whole or the lower portion of the transparent substrate is immersed in the liquid.

  In the transparent substrate inspection apparatus according to this embodiment, the illumination apparatus and the imaging apparatus may be fixed in position, or the illumination apparatus and the imaging apparatus are movable, and the illumination apparatus and the imaging apparatus are movable. It is also preferable that the imaging is performed by the imaging device while moving the device along the transparent substrate. In this case, a moving unit for moving the illumination device and the imaging device is required, but the moving unit does not need to be immersed in a liquid. Further, since the illumination device and the imaging device are moved along the transparent substrate and the illumination device and the imaging device perform imaging, the size of the illumination device and the imaging device can be reduced, and the cost can be reduced. Become.

  Further, the transparent substrate inspection method according to the present embodiment is a method of inspecting a defect of a transparent substrate having a pattern formed on a plate surface. At least one surface of the transparent substrate is a liquid whose refractive index approximates that of the transparent substrate. A step of immersing, a step of irradiating the transparent substrate with an illuminating device in a state in which the plate surface direction of the transparent substrate intersects the traveling direction of the irradiation light from the illuminating device, and the illumination across the transparent substrate Obtained by imaging with the imaging device a process of imaging the transparent substrate with an imaging device disposed on the opposite side of the device and a pattern on the substrate that is impermeable to the illumination light And a step of detecting a defect of the transparent substrate in comparison with a pattern stored in a defect detection device based on an image. For this reason, according to the transparent substrate inspection method concerning this embodiment, the same effect as the transparent substrate inspection device concerning this embodiment is acquired.

  The flat display panel according to the present embodiment includes the transparent substrate that has been inspected for defects by the transparent substrate inspection method according to the present embodiment. Therefore, the flat display panel according to the present embodiment can be a flat display panel in which the presence or absence of defects in the transparent substrate is accurately inspected. Examples of the flat display panel according to the present embodiment include a plasma display panel and a liquid crystal display device. Since the structure of these flat display panels is well known in the art, description thereof is omitted.

  FIG. 2 is a schematic front view showing the glass substrate inspection apparatus (transparent substrate inspection apparatus) 100 according to the first embodiment, and FIG. 3 is a block diagram showing the main block configuration of the glass substrate inspection apparatus 100.

  As shown in FIG. 2, the glass substrate inspection apparatus 100 according to the first embodiment is for detecting defects in a glass substrate (transparent substrate) 2 in which a fine pattern 4 is formed on a plate surface. An illuminating device 1 that irradiates light onto the substrate 2, an imaging device (camera) 3 disposed on the opposite side of the illuminating device 1 with the glass substrate 2 interposed therebetween, and a liquid 5 whose refractive index approximates that of the glass substrate 2. A liquid container 6 for storing the glass substrate 2 in the liquid 5 and immersing the glass substrate 2 in the liquid 5 and holding means (not shown) for holding the glass substrate 2 substantially horizontally in the liquid container 6 are provided.

  The illumination device 1 includes, for example, a xenon lamp, a halogen lamp, or a metal halide lamp as a light source. Note that the pattern 4 on the plate surface of the glass substrate 2 is impermeable to the illumination light of the illumination device 1.

  This illuminating device 1 is arrange | positioned under the liquid container 6, for example, and irradiates light upwards.

  The imaging device 3 is composed of, for example, a CCD line sensor or a CCD camera.

  For example, the imaging device 3 is disposed above the liquid container 6 and faces the lighting device 1 side.

  As shown in FIG. 3, the glass substrate inspection device 100 further includes a defect detection device 8 that automatically detects a defect of the glass substrate 2 based on an image acquired by the imaging device 3.

  The defect detection device 8 is acquired by, for example, a pattern storage unit 81 that stores and holds an image of a reference pattern shape (reference image) in advance, and a reference image stored and held in the pattern storage unit and the imaging device 3. A comparison / determination unit 82 that compares the image (acquired image) and determines whether or not the glass substrate 2 has a defect is provided.

  The glass substrate 2 is, for example, a glass substrate on the front side or a glass substrate on the back side of the flat display panel. Examples of the flat display panel include a plasma display panel (PDP) and a liquid crystal display panel (LCD). In these cases, the pattern 4 formed on the surface of the glass substrate 2 is, for example, an electrode. The glass substrate 2 may be a glass substrate for other purposes (other than the flat display panel).

  The shape and dimensions of the liquid container 6 and the amount of the liquid 5 in the liquid container 6 are determined by immersing the glass substrate 2 in the liquid container 6 so that the entire surface (all surfaces) of the glass substrate 2 is immersed in the liquid 5. It is set to be in the state.

  The liquid container 6 is made of a transparent material, and can transmit the irradiation light from the illumination device 1 to the imaging device 3 side through the glass substrate 2.

  Moreover, the liquid 5 in the liquid container 6 is, for example, water or an organic solvent (alcohol or the like).

  Next, the operation will be described.

  In order to detect a defect in the glass substrate 2, the glass substrate 2 is immersed in the liquid 5 in the liquid container 6 in advance, and the glass substrate 2 is held in a horizontal state by the holding means.

  That is, the glass substrate 2 is disposed so that the entire surface of the glass substrate 2 is immersed in the liquid 5 and the plate surface direction of the glass substrate 2 is orthogonal (crossed) to the traveling direction of the irradiation light from the illumination device 1. To do.

  While illuminating the glass substrate 2 with the illumination device 1 in this state and irradiating the imaging device 3 side with transmitted light that passes through the glass substrate 2, an image of the glass substrate 2 is acquired by the imaging device 3, and this image is Analysis is performed by the defect detection device 8.

  As a result, defects on the glass substrate 2, that is, defects on the pattern 4 formed on the surface of the glass substrate 2 (such as chipping, disconnection, protrusion, short circuit, etc.), foreign matter or dirt on the front or back surface of the glass substrate 2, etc. Can be detected.

  Furthermore, since the defect is automatically analyzed by the defect detection device 8, the defect of the fine pattern 4 can be suitably detected.

  Further, since the glass substrate 2 is immersed in the liquid 5 having an approximate refractive index, even if the glass substrate 2 has a scratch 7, the portion of the scratch 7 from the lighting device 1 Irregular reflection of incident light is prevented or suppressed. Therefore, only the defect of the pattern 4 can be detected without detecting the scratch 7. FIG. 2 shows an example in which the scratch 7 is formed on the back side of the glass substrate 2, but in Example 1, the entire surface of the glass substrate 2 is immersed in the liquid 5. Similarly, when formed on the front side of the glass substrate 2, the scratch 7 can be prevented from being detected.

  According to the first embodiment as described above, in the glass substrate inspection apparatus 100 for inspecting a defect of the glass substrate 2 on which the pattern 4 is formed on the plate surface, the illumination apparatus 1 that irradiates the glass substrate 2 with light, The imaging device 3 arranged on the opposite side of the lighting device 1 with the glass substrate 2 interposed therebetween, and at least one side of the glass substrate 2 (specifically, for example, both the front side and the back side) are connected to the glass substrate 2. A defect in the glass substrate 2 in a state in which the plate surface direction of the glass substrate 2 intersects (specifically, orthogonal) with the traveling direction of the irradiation light from the illumination device 1 while being immersed in the liquid 4 having an approximate refractive index. The pattern 4 on the plate surface is impermeable to the illumination light, and is based on the image captured by the image capturing device 3. Glass substrate for detecting defects It is possible to prevent the over plate surface (front surface or back surface) erroneously detects the flaw 7 when there is a flaw 7 as a defect of the pattern 4 or suppress. This is because the refractive indexes of the glass substrate 2 and the liquid 5 are close to each other, so that the refraction of light when passing through the interface between the glass substrate 2 and the liquid 5 can be prevented or suppressed. This is because the difference in luminance gradation between the part corresponding to the scratch 7 and the part without the scratch can be prevented. In this way, by preventing or suppressing the detection of scratches on the glass substrate 2 as defects in the pattern 4, only defects to be detected such as defects in the pattern 4 and foreign matters / dirt on the glass substrate 4 are detected. It can be detected accurately, and the reliability of pattern inspection is improved.

  In addition, since at least one surface of the glass substrate 2 is imaged by the imaging device 3 in a state where the glass substrate 2 is immersed in the liquid 5 having a refractive index close to that of the glass substrate 2, the surface immersed in the liquid 5 in the glass substrate 2 may be dried. Absent. Therefore, a series of inspection operations can be arbitrarily interrupted and restarted.

  In addition, the glass substrate 2 processing step includes, for example, a wet process such as a cleaning process. By incorporating the glass substrate inspection apparatus 100 according to the first embodiment into a wet facility for performing such a wet process, Space saving and quick feedback to the previous process when a defect is detected are possible.

  In the case of the first embodiment, the arrangement of the imaging device 3 and the illumination device 1 may be any arrangement as long as the arrangement is opposed to each other. That is, in the first embodiment, the example in which the imaging device 3 is on and the lighting device 1 is on the lower side is described. However, for example, the imaging device 3 may be on the lower side and the lighting device 1 may be on the upper side. May be arranged on either the left or right side, and the lighting device 1 may be arranged on either the left or right side, or any other arrangement as long as the imaging device 3 and the lighting device 1 face each other. Also good.

  FIG. 4 is a schematic front sectional view showing a glass substrate inspection apparatus (transparent substrate inspection apparatus) 200 according to the second embodiment.

  Note that among the components of the glass substrate inspection apparatus 200, the same components as those in the glass substrate inspection apparatus 100 according to the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 4, the glass substrate inspection apparatus 200 according to the second embodiment is for detecting defects in the glass substrate 2, and includes the illumination device 1, the imaging device 3, and the refractive index of the glass substrate 2. An approximate liquid 5 is stored inside, and a liquid container 6 for immersing the glass substrate 2 in the liquid 5 and a defect detection device 8 are provided.

  Also in the case of the second embodiment, imaging by the imaging device 3 is performed with the entire surface of the glass substrate 2 immersed in the liquid 5 in the liquid container 6.

  Here, in the case of the second embodiment, the liquid container 6 is made of, for example, an opaque material, but an opening 61 is formed on the bottom surface of the liquid container 6 facing the lighting device 1, and the opening 61 An inspection window 221 made of a transparent material is provided.

  Further, in the liquid container 6, a half housing 230 having an upper end opened is disposed above the inspection window 221 and above a roller group 212 described later. The lower part of the half housing 230 is immersed in the liquid 5. Further, an opening 231 is opened on the bottom surface of the half-housing 230, and an inspection window 222 made of a transparent material is disposed in the opening 231.

  That is, the space between the inspection window 222 and the inspection window 221 is filled with the liquid 5.

  The imaging device 3 is disposed in the half housing 230 and images the glass substrate 2 through the inspection window 221.

  The glass substrate inspection apparatus 200 according to the second embodiment further includes a transport mechanism 210 that transports the glass substrate 2 in a state where the entire surface of the glass substrate 2 is immersed in the liquid 5 in the liquid container 6.

  The transport mechanism 210 includes, for example, a roller group 212 composed of a plurality of rollers 211 and drive means (not shown) that drives the rollers 211 to rotate in the same direction.

  The plurality of rollers 211 constituting the roller group 212 are arranged at predetermined intervals so that the rotation axis directions thereof are parallel to each other and the glass substrate 2 can be held in a substantially horizontal state by the cooperation of the rollers 211. Yes.

  Here, in the roller group 212, a blank portion where the roller 211 is not provided, that is, an opening 212 a is formed in a portion located between the illumination device 1 and the imaging device 3.

  The opening 212a allows the irradiation light from the illumination device 1 to pass through the glass substrate 2 to the imaging device 3 side.

  Next, the operation will be described.

  In order to detect defects in the glass substrate 2, the glass substrate 2 is immersed in the liquid 5 in the liquid container 6 in advance and is held horizontally by the roller group 212.

  That is, the glass substrate 2 is disposed so that the entire surface of the glass substrate 2 is immersed in the liquid 5 and the plate surface direction of the glass substrate 2 is orthogonal to the traveling direction of the irradiation light from the illumination device 1.

  In this state, the illumination device 1 illuminates, and the image pickup device 3 acquires an image of the glass substrate 2 while conveying the glass substrate 2 in the direction of arrow A in FIG. Analysis is performed by the apparatus 8.

  As a result, the defect of the glass substrate 2 can be detected in the same manner as in the first embodiment, and even if the glass substrate 2 has a flaw, the flaw is not detected, and the defect of the pattern or the foreign matter is detected. -Only defects that should be detected, such as dirt, can be detected. In Example 2, since the entire surface of the glass substrate 2 is immersed in the liquid 5, the scratches are similarly detected regardless of whether the scratches are formed on the front side or the back side of the glass substrate 2. You can avoid it.

  According to the second embodiment as described above, the following effects can be obtained in addition to the same effects as the first embodiment.

  That is, in the case of Example 2, the liquid container 6 that stores the liquid 5, and the transport mechanism 210 that transports the glass substrate 2 in a state where the entire surface of the glass substrate 2 is immersed in the liquid 5 in the liquid container 6, In the transport mechanism 210, an opening 212 a that allows the glass substrate 2 to irradiate light from the illumination device 1 is formed in a portion located between the illumination device 1 and the imaging device 3. Since the illumination by the illumination device 1 and the imaging by the imaging device 3 are performed while the glass substrate 2 is being transported, it is not necessary for the illumination device 1 and the imaging device 3 to have dimensions over the entire surface of the glass substrate 2. Therefore, the scale of the illumination device 1 and the imaging device 3 can be reduced, and the cost can be reduced. Moreover, since the opening 212a is formed in the part located between the illuminating device 1 and the imaging device 3 in the transport mechanism 210, the transport mechanism 210 does not hinder the inspection.

  FIG. 5 is a schematic front sectional view showing a glass substrate inspection apparatus (transparent substrate inspection apparatus) 300 according to the third embodiment.

  Note that, among the components of the glass substrate inspection apparatus 300, the same components as those in the glass substrate inspection apparatus 200 according to Example 2 described above are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIG. 5, the glass substrate inspection device 300 according to the third embodiment is for detecting defects in the glass substrate 2, and includes the illumination device 1, the imaging device 3, the liquid container 6, and defect detection. An apparatus 8 and a transport mechanism 210 are provided.

  However, the glass substrate inspection apparatus 300 according to the third embodiment is configured to perform imaging by the imaging apparatus 3 in a state where only one surface of the glass substrate 2 is immersed in the liquid 5.

  That is, in the case of Example 3, the transport mechanism 210 is in a state where the lower surface of the glass substrate 2 is immersed in the liquid 5 in the liquid container 6 (the upper surface of the glass substrate 2 is not immersed in the liquid 5). The glass substrate 2 is conveyed.

  That is, the amount of the liquid 5 in the liquid container 6 and the vertical position of the transport mechanism 210 in the liquid container 6 are set so that the transport mechanism 210 can transport the glass substrate 2 in this way.

  In the case of the third embodiment, the glass substrate inspection apparatus 300 does not need to include the half housing 230.

  Next, the operation will be described.

  In order to detect a defect in the glass substrate 2, the glass substrate 2 is immersed in the liquid 5 in the liquid container 6 in advance, and the glass substrate 2 is held in a horizontal state by the holding means.

  That is, only one surface (lower surface) of the glass substrate 2 is immersed in the liquid 5, and the glass substrate 2 is placed so that the plate surface direction of the glass substrate 2 is orthogonal to the traveling direction of the irradiation light from the illumination device 1. Deploy.

  In this state, similarly to the second embodiment, the illumination device 1 performs illumination, and the conveyance mechanism 210 conveys the glass substrate 2 in the direction of arrow A in FIG. An image is acquired, and this image is analyzed by the defect detection device 8.

  As a result, as in the second embodiment, the defect of the glass substrate 2 can be detected, and even if the glass substrate 2 has a flaw, the flaw is not detected, and the defect of the pattern or the foreign matter is detected. -Only defects that should be detected, such as dirt, can be detected.

  However, in the case of Example 3, since only one side (lower surface) of the glass substrate 2 is immersed in the liquid 5, if there is a scratch on the other surface (upper surface) of the glass substrate 2, this scratch is mistaken. There is a possibility of detection.

  According to the third embodiment as described above, the liquid container 6 storing the liquid 5 and the transport mechanism for transporting the glass substrate 2 with the lower surface of the glass substrate 2 immersed in the liquid 5 in the liquid container 6. 210, and an opening 212a that allows the glass substrate 2 to be irradiated with light from the illumination device 3 is formed in a portion of the transport mechanism 210 located between the illumination device 1 and the imaging device 3. Therefore, the same effect as in Example 2 can be obtained.

  Furthermore, in the case of the third embodiment, since the imaging device 3 performs imaging with only one surface of the glass substrate 2 immersed in the liquid 5, the amount of the liquid 5 is larger than those of the first and second embodiments. Is less.

  In the second and third embodiments, the transport mechanism 210 including the plurality of rollers 211 is illustrated. However, the transport mechanism may be any system that does not cause distortion in the image, such as a mechanical chuck type or a gauging transport. .

  FIG. 6 is a schematic front sectional view showing a glass substrate inspection apparatus (transparent substrate inspection apparatus) 400 according to the fourth embodiment.

  Note that, among the components of the glass substrate inspection apparatus 400, the same components as those in the glass substrate inspection apparatus 300 according to Example 3 described above are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIG. 6, the glass substrate inspection device 400 according to the fourth embodiment is for detecting defects in the glass substrate 2, and includes the illumination device 1, the imaging device 3, and the refractive index of the glass substrate 2. An approximate liquid 5 is stored inside, and a liquid container 6 for immersing the glass substrate 2 in the liquid 5 and a defect detection device 8 are provided.

  In the case of Example 4, the liquid container 6 stores the liquid 5 until it reaches the open upper end of the liquid container 6, and the glass substrate 2 is placed substantially horizontally on the upper end opening of the liquid container 6, The imaging apparatus 3 is configured to perform imaging while the lower surface of the glass substrate 2 is immersed in the liquid 5.

  Furthermore, in the case of Example 4, the illumination device 1 and the imaging device 3 are movable in the horizontal direction A shown in FIG. 6, and the illumination device 1 and the imaging device 3 are moved (scanned) horizontally along the glass substrate 2. The imaging device 3 performs imaging.

  That is, the glass substrate inspection apparatus 400 according to the fourth embodiment includes moving means (not shown) that moves the illumination apparatus 1 and the imaging apparatus 3 in the horizontal direction A shown in FIG.

  Since these moving means do not need to be immersed in a liquid, the moving means does not need a liquidproof (waterproofing) measure. Therefore, it is possible to configure these moving means at a low cost compared to the transfer means when the transparent substrate is transferred by the transfer means. Further, since the illumination device and the imaging device are moved along the transparent substrate and the illumination device and the imaging device perform imaging, the size of the illumination device and the imaging device can be reduced, and the cost can be reduced. Become.

  Further, since the illumination device 1 and the imaging device 3 are configured to move, the inspection window 221 in the fourth embodiment has a larger horizontal dimension than that in the third embodiment. That is, the inspection window 221 has dimensions over the entire scanning range of the illumination device 1 and the imaging device 3.

  Note that the glass substrate 2 may simply be placed in the opening at the upper end of the liquid container 6. However, in the fourth embodiment, the suction surface for sucking and fixing the lower surface of the glass substrate 2 to the opening of the liquid container 6. 401 is formed, and the glass substrate 2 is positioned in the opening at the upper end of the liquid container 6.

  For this reason, for example, the glass substrate 2 does not slide on the opening of the liquid container 6 during the inspection, and the position of the glass substrate 2 is not shifted.

  Specifically, the suction surface 401 is provided with a suction pad through a suction tube, for example, although not shown, to fix the glass substrate 2 by suction or to hold the glass substrate 2 from above and below with rubber or the like. The structure is fixed by sandwiching with a cushioning material.

  Next, the operation will be described.

  In order to detect a defect in the glass substrate 2, the glass substrate 2 is previously placed in the opening at the upper end of the liquid container 6, and is adsorbed and positioned on the adsorption surface 401. As a result, the lower surface of the glass substrate 2 is immersed in the liquid 5.

  In this state, the illumination device 1 performs illumination, and the image capture device 3 acquires an image of the glass substrate 2 while moving the illumination device 1 and the image capture device 3 along the glass substrate 2 in the horizontal direction. Are analyzed by the defect detection device 8.

  As a result, similar to each of the above embodiments, the defect of the glass substrate 2 can be detected, and even if the glass substrate 2 has a flaw, the flaw is not detected and the defect of the pattern -Only defects that should be detected, such as dirt, can be detected.

  According to the fourth embodiment as described above, the liquid container 6 that stores the liquid 5 until the upper end is opened and reaches the upper end is provided, and the glass substrate 2 is placed on the upper end opening of the liquid container 6. Since the imaging apparatus 3 performs imaging with the lower surface of 2 immersed in the liquid 5, as a result, the same effects as those of the third embodiment can be obtained.

  Furthermore, in the case of Example 4, since only the lower surface of the glass substrate 2 is immersed in the liquid 5, Examples 1 and 2 in which the entire glass substrate 2 is immersed in the liquid 5, and Examples 3 in which the lower part of the glass substrate 2 is immersed There is an advantage that handling of the glass substrate 2 becomes easier.

  In the case of the fourth embodiment, a moving means (not shown) for moving the illumination device 1 and the imaging device 3 is required. However, since the moving means does not need to be immersed in the liquid 5, the moving means has a liquidproof ( No measures are required. Moreover, since the illumination by the illumination device 1 and the imaging by the imaging device 3 are performed while the illumination device 1 and the imaging device 3 are moved along the glass substrate 2, the scale of the illumination device 1 and the imaging device 3 can be reduced. And cost reduction is possible.

  In each of the above embodiments, the glass substrate 2 is exemplified as the transparent substrate. However, a transparent substrate made of a material other than glass (for example, resin) may be used.

It is front sectional drawing which shows the conventional transparent substrate test | inspection apparatus. 1 is a front view showing a glass substrate inspection apparatus according to Example 1. FIG. It is a block diagram which shows the main block structures of the glass substrate test | inspection apparatus of FIG. It is a front view which shows the glass substrate inspection apparatus which concerns on Example 2. FIG. It is a front view which shows the glass substrate inspection apparatus which concerns on Example 3. FIG. It is a front view which shows the glass substrate inspection apparatus which concerns on Example 4. FIG.

Explanation of symbols

100 Glass substrate inspection device (transparent substrate inspection device)
1 Lighting device 2 Glass substrate (transparent substrate)
3 Imaging device 4 Pattern 5 Liquid 8 Defect detection device 81 Pattern storage unit 82 Comparison determination unit 200 Glass substrate inspection device (transparent substrate inspection device)
210 Transport mechanism 211 Roller 212a Opening 300 Glass substrate inspection device (transparent substrate inspection device)
400 Glass substrate inspection device (transparent substrate inspection device)

Claims (11)

In a transparent substrate inspection apparatus for inspecting a defect of a transparent substrate in which a pattern is formed on a plate surface,
An illumination device that irradiates the transparent substrate with illumination light, an imaging device disposed on the opposite side of the illumination device, and an index of refraction that approximates at least one surface of the transparent substrate. A defect detection device that detects a defect in the transparent substrate in a state in which the plate surface direction of the transparent substrate intersects the traveling direction of the irradiation light from the illumination device while being immersed in a liquid, and the plate surface The upper pattern is impermeable to the illumination light, and detects a defect of the transparent substrate based on an image picked up by the image pickup device.   The defect detection device compares a pattern storage unit that stores a pattern on the plate surface with an image acquired by the imaging device and a pattern stored in the pattern storage unit to determine the presence or absence of a defect. The transparent substrate detection apparatus according to claim 1, further comprising a determination unit.   The transparent substrate inspection apparatus according to claim 1, wherein the imaging is performed by the imaging apparatus in a state where the entire surface of the transparent substrate is immersed in the liquid. A liquid container storing the liquid;
A transport mechanism for transporting the transparent substrate in a state where the entire surface of the transparent substrate is immersed in the liquid in the liquid container;
Further comprising
The opening which makes it possible to irradiate the light from the said illuminating device to the said transparent substrate is formed in the part located between the said illuminating device and the said imaging device in the said conveyance mechanism. The transparent substrate inspection apparatus described in 1.   The transparent substrate inspection apparatus according to claim 1, wherein the imaging is performed by the imaging apparatus in a state where only one surface of the transparent substrate is immersed in the liquid. A liquid container storing the liquid;
A transport mechanism for transporting the transparent substrate in a state where the lower surface of the transparent substrate is immersed in the liquid in the liquid container;
Further comprising
6. An opening that allows the light from the illumination device to irradiate the transparent substrate is formed in a portion of the transport mechanism that is positioned between the illumination device and the imaging device. The transparent substrate inspection apparatus described in 1.   The transparent substrate inspection apparatus according to claim 4, wherein the transport mechanism includes a plurality of rollers that transport the transparent substrate. Further comprising a liquid container storing the liquid until the upper end is open and reaches the upper end;
2. The structure in which the imaging is performed by the imaging apparatus in a state where the transparent substrate is placed in an opening at an upper end of the liquid container and a lower surface of the transparent substrate is immersed in the liquid. Or the transparent substrate inspection apparatus of 2.   The transparent substrate inspection apparatus according to claim 1, wherein the imaging device performs the imaging while moving the illumination device and the imaging device along the transparent substrate. In a method for inspecting a defect of a transparent substrate having a pattern formed on a plate surface,
The transparent substrate in a state where at least one surface of the transparent substrate is immersed in a liquid having a refractive index approximate to that of the transparent substrate, and the plate surface direction of the transparent substrate intersects the traveling direction of the irradiation light from the illumination device. A process of irradiating the substrate with an illuminating device, a process of imaging the transparent substrate with an imaging device disposed on the opposite side of the illuminating device across the transparent substrate,
The defect of the transparent substrate is compared with the pattern stored in the defect detection device based on the image obtained by imaging the pattern on the substrate that is impermeable to the illumination light by the imaging device. The process of detecting
A transparent substrate inspection method comprising: A flat display panel comprising the transparent substrate, the defect being inspected by the transparent substrate inspection method according to claim 10.

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