JPH087159B2 - Identification type defect detection device for transparent plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a transparent plate material, such as a glass plate or a plastic plate, by scanning a light spot on a plate material (hereinafter referred to as a transparent plate material) that transmits at least light. The present invention relates to a flying spot type defect detection device for detecting defects existing in the above, and more particularly to an identification type defect detection device for a transparent plate material capable of identifying and detecting the type, size, position, etc. of the detected defect.

[Conventional technology]

The defect detection device for detecting defects existing in the translucent plate material,
For example, in a transparent glass plate production line, the defects existing in the transparent glass plate to be manufactured are detected, and the detection result is fed back to the transparent glass plate manufacturing process to prevent the occurrence of defects at the occurrence position, It is required to improve the yield.

In a conventional transparent glass plate defect detection device, for example, as is known in Japanese Patent Laid-Open No. 51-29988, the presence of the glass plate by detecting only reflected light with respect to irradiation light by a light receiver. To know the drawbacks, or JP-A-51-11
As known from Japanese Patent Publication No. 84, there is one that detects a defect existing in a glass plate by detecting only transmitted light with respect to irradiation light by a light receiver.

[Problems to be solved by the invention]

The defect detection device disclosed in Japanese Patent Laid-Open No. 51-29988 described above can detect defects on the glass surface, but cannot detect defects inside the glass.

On the contrary, the defect detection device disclosed in Japanese Patent Laid-Open No. 51-1184 can detect defects inside the glass, but defects on the glass surface cannot be detected or are very difficult to detect. There is a problem.

Further, the defect detection device as described above cannot identify the type of defect (foreign matter, bubble, stick, drip, etc.),
Further, since one light receiver detects bubbles and foreign matter at the same level, there is a defect that foreign matter is overlooked and bubbles and the like are overlooked.

Furthermore, since the conventional defect detection device cannot accurately detect the size of the defect, the quality of the transparent glass plate after cutting is divided into a high grade and a low grade during the manufacturing process, so-called 2 It was impossible to adopt the grade sampling plate method.

An object of the present invention is to solve the above-mentioned problems and to provide an identification type defect detection device capable of detecting defects of a transparent plate material with high accuracy and high speed.

[Structure of Invention]

The light-transmissive plate material discrimination type defect detection device of the present invention is a scanning means for scanning the entire light-transmissive plate material traveling in the length direction with a light spot in the width direction; Light receiving means having a plurality of light receivers respectively receiving at least two kinds of light among reflected light and reflected scattered light; photoelectric conversion means for converting the light received by the plurality of light receivers into electric signals; Electric signal processing means for processing the electric signal from the converting means to generate defect data including information on type and size of the defect, and defect data taken in from the electric signal processing means and taken in defect data Defect data capturing means for performing a combination process to form a defect pattern representing the type and size of the defect, and a defect identification pattern table for holding the defect pattern from the defect data capturing means in advance. Against the Le, it is characterized by comprising an information processing means for identifying the type and size of at least drawbacks.

[Action]

For example, the disadvantages of existing glass plates include bubbles formed by bubbles remaining inside the glass plate, foreign substances formed when foreign substances remain inside the glass plate, and almost all melted foreign substances leaving a tail inside the glass plate. There are a brush formed by remaining in a pulled shape, a drip formed by the tin of the bath adhering to the surface of the glass plate, and the like.

When such a defect exists in the glass plate, when a light spot is projected on the defect, the states of transmission, transmission scattering, reflection, and reflection scattering differ depending on the type of the defect. Focusing on this fact, the inventors of the present application accumulated a large amount of data by experiments in order to see how the states of transmission, transmission scattering, reflection, and reflection scattering change depending on the types of defects of the glass plate. A part of the contents obtained by analyzing these data will be described as an example.

As shown in FIG. 2, when the light beam 3 is projected onto the defect 2 existing on the transparent glass plate 1 at a constant incident angle α with respect to the normal line, the fluff, the foreign matter, and the bubbles generate transmitted scattered light. In particular, in the case of a bush, the near paraxial transmitted scattered light 5 that is closest to the optical axis of the transmitted light 4 is generated, and in the case of a foreign substance, the paraxial transmitted scattered light 6 that is close to the optical axis of the transmitted light 4 is generated. In this case, the far-axis transmitted scattered light 7 that is far from the optical axis of the transmitted light 4 is generated. Also,
The light quantity of the transmitted light 4 decreases for bubbles, foreign matters, humps, and drip, and the light quantity of the reflected light 8 increases for drip.

Therefore, a light receiver for individually detecting transmitted light, near-paraxial transmitted scattered light, paraxial transmitted scattered light, far-axis transmitted scattered light, and reflected light is provided to change the amount of transmitted light and reflected light and The types of defects can be identified by detecting the presence or absence of transmitted scattered light, paraxial transmitted scattered light, and far axis transmitted scattered light.

The above relationships are summarized in Table 1. The circles in the table indicate with which light the defect type can be identified.

Further, the inventors of the present application have found that the amount of light detected by each light receiver is proportional to the size of the defect. Therefore, it is possible to determine the size of the defect by detecting the size of the amount of light detected by each light receiver.

The above is a part of the contents known by the inventor of the present application,
In addition to this, it is known that there is a certain relationship between the types of defects and the state of reflection and scattering.

Based on the above concept, the identification type defect detecting device of the present invention is a flying spot type defect detecting device, and in the flying spot type defect detecting device, transmitted light, near paraxial transmitted scattered light, paraxial transmitted scattered light, far axis transmitted scattered light, reflected light, A plurality of light receivers for detecting at least two kinds of light among the reflected and scattered light respectively are provided, the light from each light receiver is converted into an electric signal, and the obtained electric signal is processed to determine the kind and size of the defect. Defect data including information indicating the level is generated, these defect data are further processed to create a defect pattern consisting of a bit pattern corresponding to one defect of the glass plate, and the defect pattern thus obtained is Basically, the type, size, etc. of the defect are determined by collating with a defect identification pattern table created in advance.

Further, the identification type defect detection device of the present invention is adapted to detect the position of the defect of the glass plate, and finally, at least the type of defect, the size of the defect and the position of the defect are identified and detected. To do.

Therefore, the identification type defect detection device of the present invention is provided in a glass plate manufacturing line, a defect is detected, its type and size are identified, and the result is fed back to the glass plate manufacturing process to generate a defect. Can be prevented at the occurrence location, and the product yield can be improved.

In addition, for example, if the defect identification pattern table includes quality judgment conditions of high grade and low grade, it is possible to cut the cut plate in the middle of the manufacturing process into high grade and low grade. It is possible to build a system.

Further, when a cut plate for a windshield of an automobile composed of a high-grade transparent area region and a low-grade outer peripheral area region is used, if the identification type defect detection device of the present invention is used, the types of defects, Since the size and position can be detected, the plate yield can be increased.

The operation of the present invention has been described above in the case where the object to be inspected is a glass plate, but it is clear that the present invention can be applied not only to a glass plate but also to a defect detection of at least a light transmitting plate material such as a plastic plate. .

〔Example〕

Next, an embodiment of the identification type defect detection device of the present invention will be described.

FIG. 1 is a block diagram showing an outline of the entire configuration of an identification type defect detecting device for a transparent glass plate which is an embodiment of the present invention. The identification type defect detection device of the present embodiment, the laser beam is reflected by the rotating polygon mirror, the scanner 11 for scanning the laser spot on the transparent glass plate during traveling, and the laser spot scanned the defect of the transparent glass plate. At this time, a plurality of light receivers 12 that receive transmitted light, transmitted scattered light, and reflected light, a photoelectric converter 13 that converts the light received by each light receiver into an electric signal, and an electric signal from the photoelectric converter are processed. Electrical signal processing circuit 14 for generating defect data including defect type and size information.
And the defect data generated by this electric signal processing circuit, the signal processing clock, and the line synchronization signal are taken in, and a defect pattern consisting of a bit array representing the type and size of the defects existing in the glass plate is formed from the defect data. , A defect data fetching circuit 15 for adding position information thereto, receiving a defect pattern and position information from the defect data fetching circuit 15, collating the defect pattern with a defect identification pattern table 16 held in advance, The information processing device 17 identifies the type, size, etc., and sends the identification result and position information to a higher-level information processing device.

In the following description, it is assumed that the scanner 11, the light receiver 12, and the photoelectric converter 13 form a defect detector 20.

FIG. 3 is a perspective view of the defect detector 20, in which the photodetector is exaggerated for clarity.

FIG. 4 is a schematic configuration diagram of this defect detector as seen from a direction perpendicular to the traveling direction of the transparent glass plate. In FIGS. 3 and 4, the same elements are designated by the same reference numerals. Shows.

The scanner 11 receives a laser light source 21 that emits a laser light and a laser light 26 from the laser light source 21, and the transparent glass plate 1
Axis 22 parallel to the direction in which the vehicle travels (hereinafter referred to as the Y-axis direction)
A rotary polygon mirror 23 that rotates at high speed around the transparent glass plate 1
A parallel mirror 25 for plate thickness correction that can change the angle by rotating about an axis 24 that is parallel to the direction in which the Y axis travels, that is, parallel to the width direction of the glass plate (hereinafter referred to as the X axis direction). It has and. The position of the laser light source 21 shown in FIG. 4 is shown differently from the actual position, but this is to avoid obscuring the drawing.

The scanner configured as described above is installed above the traveling transparent glass plate 1.

Laser light 26 emitted from the laser light source 21 is incident on a rotating polygon mirror 23 that rotates at a high speed, the laser light 26 is shaken in the X-axis direction by the rotating polygon mirror 23, reflected by a parallel mirror 25, and then travels. The glass plate is projected on the transparent glass plate 1,
Scan in the axial direction. The laser beam 26 repeatedly scans the transparent glass plate 1 each time the reflecting surface changes due to the rotation of the rotary polygon mirror 23. Since the transparent glass plate 1 runs in the Y-axis direction, the entire surface of the glass plate is scanned by the laser light.

As shown in FIG. 4, the laser light 26 is
The transparent glass plate 1 is projected at an incident angle α in the Y-axis direction with respect to a normal line perpendicular to the glass plate surface. This is to prevent the light reflected on the back surface of the transparent glass plate 1 and subsequently reflected on the front surface from interfering with the transmitted light. In addition,
It is desirable that the value of α be 13 ° or more.

Next, the arrangement and configuration of the light receiver will be described. One optical receiver D1 for detecting the transmitted light 27 and two optical receivers for detecting the near paraxial transmitted scattered light are provided on the side opposite to the side where the scanner is provided, that is, below the transparent glass plate 1. D2
_A , D2 _B and two photo detectors D for detecting paraxial transmitted scattered light
3 _A , D3 _B, and two receivers D for detecting far-axis transmitted scattered light
Place 4 _A and D4 _B. On the other hand, one light receiver D5 for detecting the reflected light 28 is arranged above the transparent glass plate 1.

The plurality of light receivers basically have the same structure and have a linear light receiving surface elongated in the X-axis direction. The structure of the light receiver D1 will be described below as a representative.

FIG. 5 is a perspective view of the light receiver D1. This receiver D1
A large number of optical fibers 31 are arranged, and one end of the optical fibers 31 is arranged in two rows as shown in the figure, and is embedded and fixed in resin or the like to form a light receiver main body 32. The end faces 33 of the arrayed optical fibers 31 are gathered to form an elongated linear light receiving surface 34. The other ends of the optical fibers are bundled and connected to a photomultiplier tube described later.

Although the optical fibers are arranged in two rows in the above example, the arrangement method is not limited to this.

When the photodetectors D1, D2 _A , D2 _B , D3 _A , D3 _B , D4 _A , and D4 _B for detecting transmitted light and transmitted scattered light having the above structure are arranged, the transmitted light 27 shown in FIG. The respective light receivers were arranged such that the light receiving surface was located within each effective light receiving angle with respect to the axis. Table 2 shows an example of the relationship between each light receiver and the effective light receiving angle.

Photoreceiver D1 D2 _A ， D2 _B ， D3 _A ， D3 _B ， D
Fig. 6 shows the state of 4 _A and D4 _B as seen from the light receiving surface side. The length direction of the light receiving surface of each light receiver is parallel to the X-axis direction. The use of two photodetectors for detecting the near-paraxial transmitted scattered light, the paraxial transmitted scattered light, and the far-axis transmitted scattered light, respectively, is to prevent the generated transmitted scattered light from being overlooked.

Further, as shown in FIGS. 3 and 4, the light receiving surfaces of the light receiving device D1 for the transmitted light and the light receiving surfaces of the light receiving devices D2 _A , D2 _B for the near transmitted scattered light which are arranged in close proximity to each other. The positions of are different from each other in order to prevent the transmitted light from being diffusely reflected by the light receiving surface of the light receiver D1 and entering the light receivers D2 _A and D2 _B.

The light receiver D5 for detecting the reflected light 28 may be configured by an optical fiber as described above, but a scattering box is used, and the light collected by the scattering box is an optical fiber, and a photomultiplier tube described later is used. It may be something like sending to. in this case,
It is preferable that a mask having a slit is provided on the light-receiving surface of the scattering box to block unnecessary light.

As shown in FIG. 3, the defect detector 20 (FIG. 1) further includes five photomultiplier tubes PM1, PM2, PM3, as photoelectric converters.
The photomultiplier tube PM1 is equipped with PM4 and PM5, and the other end of the optical fiber of the photodetector D1 is connected to the photomultiplier tube PM1, and the other end of the optical fibers of the photodetector D2 _A and D2 _B is bundled with the photomultiplier tube PM2. The other ends of the optical fibers of the photodetectors D3 _A and D3 _B are bundled and connected to the photomultiplier tube PM3, and the photomultiplier tube PM4 is connected to the photomultiplier tube PM4 of the optical fibers of the photodetectors D4 _A and D4 _B. The other end is bundled and connected, and the other end of the optical fiber of the photodetector D5 is connected to the photomultiplier tube PM. Each photomultiplier tube converts the light received by each light receiver into an electric signal.

Further, although not shown, an optical fiber for forming a start pulse is provided between the rotary polygon mirror 23 and the parallel mirror 25 of the scanner, and photoelectric conversion for converting the light received by this optical fiber into an electric signal. And a pulse shaper to form the start pulse ST. This start pulse ST is used as a scan start signal in a defect data fetch circuit described later.

If the plate thickness of the transparent glass plate 1 changes, the optical paths of the transmitted light, the transmitted scattered light, and the reflected light may change, and the light may not enter the light receiving surface of each light receiver. In such a case, by rotating the parallel mirror 25 and changing the optical path of the incident light to the glass plate 1, for example, the optical paths of the transmitted light and the transmitted scattered light can be made unchanged. If the parallel mirror is adjusted so that the optical paths of the transmitted light and the transmitted scattered light do not change, the optical path of the reflected light changes, so the light receiver D5 itself may be moved, or the light receiver D5 may be a scattering box. In some cases, if a mask is provided, this mask may be moved.

Now, the operation of the defect detector having the above configuration will be described in the case where the transparent glass plate 1 has a defect and the laser beam scans this defect.

When there is a defect in the transparent glass plate, when the laser beam hits this defect, the amount of transmitted light and reflected light changes depending on the type of defect (foreign matter, bubble, stick, drip), and at the same time transmitted scattered light occurs. To do.

For example, if the defect type is a bush, and the incident laser light hits the bush, the amount of transmitted light changes and
Proximity paraxial transmission scattered light is generated. The change in the amount of transmitted light is detected by the photodetector D1 and sent to the photomultiplier tube PM1.
It is converted into an electric signal. On the other hand, the near paraxial transmitted scattered light is
The light is incident on the light-receiving surfaces of the photodetectors D2 _A and D2 _B. The received near paraxial transmission scattered light is sent to the photomultiplier tube PM2 and converted into an electric signal.

Similarly, for example, when the defect type is foreign matter, when the incident laser beam hits the foreign matter, the amount of transmitted light changes and paraxial transmitted scattered light is generated at the same time. This transmitted scattered light is
The light received by the photodetectors D3 _A and D3 _B is sent to the photomultiplier tube PM3 and converted into an electric signal.

Similarly, for example, when the type of defect is bubbles, when the incident laser light hits the bubbles, the amount of transmitted light changes and, at the same time, far-axis transmitted scattered light is generated. The far-axis transmitted scattered light is received by the photo detectors D4 _A and D4 _B , and the received light is sent to the photomultiplier tube PM4 and converted into an electric signal.

Similarly, for example, when the type of defect is a drip, when the incident laser beam hits the drip, the amount of transmitted light changes and the amount of reflected light changes at the same time. This change in reflected light is detected by the photodetector D5, sent to the photomultiplier tube PM5, and converted into an electric signal.

As described above, from the defect detector 20, the change in the light amount of the transmitted light and the reflected light generated due to the defects existing in the transparent glass plate, the near paraxial transmitted scattered light, the paraxial transmitted scattered light, and the far axial transmitted scattering is performed. The light is sent to the electric signal processing circuit 14 (FIG. 1) as an electric signal.

Next, each photomultiplier tube of the defect detector PM1, PM2, PM3, PM4,
The configuration of the electric signal processing circuit 14 that processes the electric signal sent from the PM 5 to generate the defect data including the information on the type and size of the defect will be described.

FIG. 7 shows an example of the electric signal processing circuit. This electrical signal processing circuit is used for each photomultiplier tube PM1, PM2, PM3, PM4, PM5.
It is composed of defect data generators CT1, CT2, CT3, CT4, CT5 which respectively process the electric signals from the above to generate defect data.

The defect data generation unit CT1 includes an amplifier 411 that amplifies an electric signal from the photomultiplier tube PM1, a minus differentiator 412 that differentiates a falling edge of the signal from the amplifier 411, and a signal level from the minus differentiator 412. A comparator 413 for comparing two detection levels, pulse shapers 414, 415 for pulse-shaping the two signals output from the comparator 413, and a comparator 416 for comparing the signal from the amplifier 411 with one detection level. , A width detector 417 for comparing the width of the signal from the comparator 416 with two width determination levels, and a pulse shaper 41 for pulse-shaping the two signals output from the width detector 417, respectively.
Composed of 8,419.

The defect data generation unit CT2 includes an amplifier 420 that amplifies the electric signal from the photomultiplier tube PM2, a plus differentiator 421 that differentiates the rising edge of the signal from the amplifier 420, and a plus differentiator 4
It is composed of a comparator 422 for comparing the level of the signal from 21 with two detection levels, and pulse shapers 423, 424 for respectively pulse-shaping the two signals output from the comparator 422.

Since the defect data generation units CT3, CT4, and CT5 have the same configuration as the defect data generation unit CT2, only the elements are numbered and the description thereof is omitted.

Next, the operation of the electric signal processing circuit 14 will be described.
This will be described with reference to the waveform diagrams of FIGS. 9, 9 and 10.

First, the operation of the defect data generation unit CT1 will be described. The defect data generation unit CT1 generates defect data including information on the type and size of the defect from the electric signal obtained by converting the transmitted light detected by the light receiver D1 by the photomultiplier tube PM1.

The amplifier 411 amplifies the electric signal sent from the photomultiplier tube PM1. Here, FIG. 8 (a) shows the output voltage waveform of the amplifier 411 when the laser beam of the defect detector scans the transparent glass plate containing no defects one time in the X-axis direction. This waveform is the transmitted light received by the light receiving unit D1 during one scan from time t ₁ to time t _2, the show that the output level is E volts. Thus, the light receiver D1 constantly receives the transmitted light during one scanning period.

When the transparent glass plate has a defect, when the laser beam is projected onto the defect, the amount of transmitted light decreases, and a falling pulse 51 is generated in the output waveform as shown in FIG. 8 (b). . For convenience of explanation, the falling pulse 51 is shown in an exaggerated manner, falling at time t _3, it is assumed that rises at time t _4. The size of the falling level of the falling pulse 51 is proportional to the size of the defect, and the width of the falling pulse (from time t ₃ to t ₄ ) also increases as the defect increases.

In the minus differentiator 412, the output from the amplifier 411 is minus differentiated, and as shown in FIG. 8C, the differentiated pulse 52 which rises at the falling time t ₃ of the falling pulse 51 is output. The magnitude of this differential pulse is proportional to the falling level of the falling pulse 51.

The differential pulse 52 from the minus differentiator 412 is input to the comparator 413. The comparator 413 has two detection levels d ₁₁ and d ₁₂ (d ₁₁ <d ₁₂ ) as shown in the waveform of FIG. 8C, and these detection levels and the input differential pulse 52 Compare with the falling level.

The comparator 413 outputs a pulse from the first output terminal 440 when the falling level of the input differential pulse is higher than the detection level d ₁₁ , and outputs the second output when it is higher than the detection level d _12. Output a pulse from terminal 441. These pulses are shaped by pulse shapers 414 and 415, respectively, and are output as defect data D ₁₁ and D ₁₂ . In the case of the differential pulse 52 shown in FIG. 8 (c), the falling level is the detection level.
Since it is larger than d _{11 and} smaller than d ₁₂ , defect data D ₁₁ as shown in FIG. 8D is output. The difference between the defect data D ₁₁ and D ₁₂ as described above represents the size of the defect.

On the other hand, the electric signal from the amplifier 411 is input to the comparator 416 and then to the width detector 417, and the width judgment processing is performed. This width determination process is used to determine the size of a defect, which is used as a determination criterion in so-called two-grade plate-making, in which a glass plate after cutting is divided into a high-quality grade and a low-quality grade for plate-making. Is performed to generate defect data including.

The width determination process will be described with reference to the waveform chart of FIG. The waveform of FIG. 9 (a) is an enlarged view of the time width of the falling pulse 51 portion of the waveform of FIG. 8 (b). The comparator 416 has one detection level d, and when the falling level of the falling pulse 51 exceeds the detection level d, as shown in FIG. 9 (b),
A pulse having a width equal to the width w (from time t ₃ to t ₄ ) when the falling pulse 51 is sliced at the detection level d
Outputs 53.

The width detector 417 has two width determination levels w ₁₁ , w ₁₂ (w ₁₁ <
w ₁₂ ), and compares these judgment levels with the width w of the input pulse 53. The width detector 417 outputs a pulse from the first output terminal 442 when the width w is larger than the judgment level w _11, and outputs a pulse from the second output terminal 443 when the width w is larger than the judgment level w _12. . These pulses are shaped by pulse shapers 418 and 419, respectively, and output as defect data w ₁₁ and w ₁₂ . In the case of the pulse 53 shown in FIG. 9B, the width w is larger than the judgment level w _{11 and} smaller than w ₁₂ , so that the defect data w ₁₁ as shown in FIG.
Is output.

The difference between the defect data w ₁₁ and w ₁₂ as described above represents the size of the defect. These defect data w ₁₁ and w ₁₂ are used as the judgment data when the glass plate of a low grade is sampled in the 2 grade plate.

Next, referring to the waveform diagram of FIG. 10, the defect data generator CT
The operation of 2 will be described. The defect data generator CT2 is the receiver D2.
_The near paraxial transmitted scattered light detected by _A and D2 _B is a photomultiplier tube.
Defect data including information on the type and size of the defect is generated from the electric signal converted by PM2. Photomultiplier PM
From 2, the electric signal is sent only when the defect (bush) is scanned by the laser beam. FIG. 10 (a) shows the waveform of the electrical signal from the amplifier 420 when the defect is scanned. A rising pulse 61 is generated between time t ₅ and time t ₆ . The plus differentiator 421 positively differentiates the output from the amplifier 420, and as shown in FIG. 10B, outputs a differentiation pulse 62 which rises at the rising time t ₅ of the rising pulse 61. The magnitude of this differential pulse is proportional to the rising level of the rising pulse 61.

The differential pulse 62 from the plus differentiator 421 is input to the comparator 422. The comparator 422 has two detection levels d ₂₁ and d ₂₂ (d ₂₁ <d ₂₂ ) as shown in the waveform of FIG. 10 (b), and these detection levels and the differential pulse 62 to be input. Compare with the rising level.

The comparator 422 outputs a pulse from the first output terminal 444 when the rising level of the input differential pulse 62 is higher than the detection level d _21, and the second output terminal when it is higher than the detection level d _22. Output pulse from 445. These pulses are shaped by pulse shapers 423 and 424, respectively, and are output as defect data D ₂₁ and D ₂₂ . In the case of the differential pulse 62 shown in FIG. 10 (b), the rising level is the detection level.
Since it is larger than d _{21 and} smaller than d ₂₂ , defect data D ₂₁ as shown in FIG. 10 (c) is output. The difference between the defect data D ₂₁ and D ₂₂ as described above represents the size of the defect (bush).

After that, by the same operation, the defect data generators CT3, CT4,
The CT5 outputs defect data D ₃₁ , D ₃₂ , D ₄₁ , D ₄₂ , D ₅₁ , D ₅₂ related to foreign matter, bubbles, and drip, respectively.

As described above, from the electric signal processing circuit 14, the defect data D ₁₁ , D including the information indicating the type and size of the defect.
₁₂ , ..., D ₅₂ are output and sent to the defect data acquisition circuit 15 (FIG. 1). In the following description, it is assumed that the defect data as a pulse corresponds to bit "1".

 Next, the configuration of the defect data acquisition circuit 15 will be described.

FIG. 11 shows an example of the configuration. This defect data acquisition circuit consists of an X-axis counter 71, an OR unit 72, and a frequency divider circuit.
73, Y-axis counter 74, continuity determination unit 75, FIFO memory
76 and the continuity determination unit 75 is a defect data compression unit.
77, an X-axis continuity determination unit 78, and a Y-axis continuity determination unit 79.

The X-axis counter 71 uses the clock CLK for X-coordinate division.
And is reset by a start pulse ST which is a scanning start signal. This start pulse
As described above, the ST is obtained by extracting the laser light reflected by the rotary polygon mirror 23 of the defect detector 20 at a specific position with a glass fiber, performing photoelectric conversion, and shaping the waveform. X-axis counter
71 outputs the counter value when the defect data is taken in to the continuity determination unit 75 as X coordinate position data.

The OR unit 72 is a unit for accumulating defect data for a plurality of scans from the electric signal processing circuit and outputting it at a predetermined timing. For such an OR unit, Japanese Patent Publication No. 56-39419 “Defect detecting device” is disclosed. ].

The frequency dividing circuit 73 frequency-divides the line synchronization signal PG corresponding to the moving distance of the glass plate in the line direction, which is supplied from a pulse generator (not shown), and inputs it to the OR unit 72.
The OR unit 72 outputs the accumulated defect data to the continuity determination unit 75 at the timing of the divided line synchronization signal PG.

The Y-axis counter 74 counts the frequency-divided line synchronization signal PG from the frequency dividing circuit 73, and when the defect data is input, outputs the count value to the continuity determination unit 75 as Y-coordinate position data. The Y-axis counter 74 is reset by software.

FIG. 12 shows an example of the OR unit 72. This OR unit
72, a plurality of types of flaw data D _11, D _12, ..., corresponding respectively to D _52, the OR circuit OR _11, OR _12, and ... OR _52, a random access memory _{RAM 11, RAM 12, ...,} RAM 52 , And gate circuits G ₁₁ , G ₁₂ , ..., G ₅₂ .

FIGS. 13 and 14 are diagrams to help understand the operation of the OR unit 72. FIG. 13 shows scanning by the laser spot, clock CLK, and line synchronization signal PG after frequency division.
FIG. 14 is a schematic diagram showing the relationship with the, and FIG. 14 is a diagram showing a state in which the defect data D ₁₁ is stored in the RAM ₁₁ of the OR unit. With reference to these drawings, the OR unit 72 has defect data as an example.
The operation of accumulating D ₁₁ will be described. It is assumed that the glass plate is scanned n times in the X-axis direction by the laser spot during the line synchronization signal PG after frequency division. It is also assumed that each RAM of the OR unit 72 has up to 1000 addresses. The address of each RAM corresponds to what number clock the clock CLK is.

Now, as shown in FIG. 13, when the transparent glass plate 1 has the next point 80, the defect data D ₁₁ inputted from the electric signal processing circuit in the first scanning is written in the RAM ₁₁ , and the address 502,
Bit “1” stands at address 503. Flaw data D ₁₁ that has been entered in the second scanning after the OR is taken in flaw data and the logical OR circuit OR ₁₁ read from the RAM _11, is re-written to RAM _11, ... n-th scan flaw data D ₁₁ entered in, after being OR is taken in flaw data and the logical OR circuit OR ₁₁ read from the RAM _11, is re-written to RAM _11, and finally to 504 addresses from the address address 501 Bit "1"
Is stored. The defect data D ₁₁ stored in the RAM ₁₁ in this way passes through the gate circuit G ₁₁ at the timing of the line synchronization signal PG divided by the divider circuit 73 and the continuity determination unit 75.
Is output to

The continuity determination unit 75 determines the continuity of the compressed defect data in the X-axis direction with the defect data compression unit 77 that compresses the defect data from the OR unit 72 and outputs the type of the compressed defect data. , An X-axis continuity determination unit 78 that outputs a start address and an endless address in the X-axis direction, and determines the continuity of the compressed defect data in the Y-axis direction, and outputs the start address and the end address in the Y-axis direction. It is composed of a Y-axis continuity determination unit 79.

Now, the operation of the continuous determination unit 75 having such a configuration will be described in the fifteenth aspect.
Description will be made with reference to the drawings and FIG. FIG. 15 is a diagram for conceptually explaining the operation of the defect data compression unit 77 for compressing defect data, and FIG. 16 describes the operation of the X-axis continuity determination unit 78 and the Y-axis continuity determination unit 79. For this reason, it is a diagram showing an example of a bit array of defect data after compression.

From the OR unit 72, defect data D ₁₁ , D ₁₂ ,
, _D52 is output, but as shown in FIG. 15, the defect data for each type has a two-dimensional bit array in the X-axis address and Y-axis address directions. Now, considering the three-dimensional space, these two-dimensional array defect data D ₁₁ , D ₁₂ ,
…, If D ₅₂ is arranged in the Z-axis direction, OR
From the unit 12, a three-dimensional defect data group D ₁₁ , D ₁₂ , ...,
It can be considered that D ₅₂ is output. The defect data compression unit 77 converts the three-dimensional defect data group D ₁₁ , D ₁₂ , ..., D ₅₂ into
Two-dimensional defect data compressed by ORing all defect data in the Z-axis direction corresponding to the X-axis address and Y-axis address
Form the DB. FIG. 15 shows an example in which the bit “1” is set only in the defect data D ₁₁ and the defect data D ₅₂ .

FIG. 16 shows an example of a bit array of defect data compressed based on the above idea.

The X-axis continuity determination unit 78 and the Y-axis continuity determination unit 79 respectively check the continuity of the bit "1" in the X-axis direction and the Y-axis direction, and detect the discontinuity of the bit "1". It is determined whether or not to connect in the X-axis direction and the Y-axis direction based on the parameter for the detected break.

FIG. 16 (a) shows a defect data block combined by the continuous determination when the parameters of the X-axis continuous determination section 78 and the Y-axis continuous determination section 79 are both 0. X-axis continuity determination unit 78
From this, 500 is output as the X-axis start address and 503 is output as the X-axis end address of this defect data block. On the other hand, the Y-axis continuity determining section 79 outputs address 100 as the Y-axis start address and address 103 as the Y-axis end address of the defect data block.

FIG. 16B shows a defect data block synthesized by the continuous determination when the parameters of the X-axis continuous determination section 78 and the Y-axis continuous determination section 79 are both 1. If the parameter is 1, even if there is a discontinuity of bit "1" in one address, they are combined and a defective data block as shown is synthesized. In this case, from the X-axis continuity determination unit 78, the 500th address as the X-axis start address of this defect data block is
Address 503 is output as the X-axis end address. On the other hand, from the Y-axis continuity determination unit 79, Y of the defect data block
Address 101 is output as the axis start address and address 103 is output as the Y axis end address. In this way, by performing the continuous determination of interpolating the discontinuity of the bit “1” and combining, when one defect is scanned by the laser spot, the timing of generation of defect data from a plurality of light receivers is deviated. In such a case, it is possible to recognize these as defect data from one defect.

When the continuity of the bit “1” is interrupted, the Y-axis continuity determining unit 79 uses the bit “1” standing in the defect data block, that is, the defect data type as the defect pattern, and the X-axis continuity determining unit 78. The Y-axis continuity determining unit 79 outputs the start address and end address of the defect data block in the X-axis direction and the start address and end address of the Y-axis direction to the FIFO memory 76 as defect position information. The Y-axis continuity determination unit 79 has a function of forcibly cutting off the bit "1" continuation in the Y-axis direction for a predetermined length and outputting the defect pattern and position information to the FIFO memory 76. There is.

The FIFO memory 76 stores the sent defect pattern and position information, and transfers it to the memory of the information processing device 17 by direct memory access.

FIG. 17 shows information processing measures from the defect data acquisition circuit 15.
The format of the data transferred to 17 is shown. This data consists of a defect pattern consisting of a bit string representing the type and size of one defect existing in the glass plate, position information representing the position of the defect, and the like.

The information processing device 17 holds in advance a defect identification pattern 16 for determining the type of defect, the size of the defect, the grade, etc., and compares it with the defect pattern sent from the defect data acquisition circuit 15, In addition to identifying the type, size, grade, etc., the position of the defect is identified from the position information sent from the defect data acquisition circuit 15, and these identification results are sent to the upper information processing apparatus. The higher-level information processing device controls the manufacturing line process, the plate collecting process, etc. based on the sent information.

Although the identification type defect detection device for transparent glass has been described above, the present invention is not limited to this embodiment, and it goes without saying that various modifications and changes can be made within the scope of the present invention.

For example, by further providing a plurality of light receivers for detecting the reflected and scattered light and increasing the detection level and the width judgment level in the electric signal processing circuit, more detailed defect data can be obtained, and the defect type, size, etc. It is possible to improve the identification accuracy of.

Further, the light receivers may be arranged such that the length direction of the light receiving surface forms an angle with the X-axis direction.

〔The invention's effect〕

As described above, according to the present invention, it is possible to detect defects on the surface and inside of the translucent plate material, and the types of defects,
Since the size and the like can be detected with high accuracy and at high speed, the detection result can be fed back to the glass plate manufacturing process to prevent the occurrence of defects at the occurrence position and improve the product yield.

Moreover, since the large defect to the small defect can be detected with high accuracy by using the identification type defect detection device of the present invention, it is possible to separate the high-grade and low-grade cutting plates, and thus the plate yield Can be improved.

Further, by using the identification type defect detection device of the present invention, even when a cutting plate for an automobile windshield consisting of a high-grade perspective area region and a low-grade outer peripheral area region is used, The yield can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing the basic configuration of an embodiment of the identification type defect detection device of the present invention, FIG. 2 is a diagram showing transmitted light and transmitted scattered light, and FIG. 3 is a perspective view of a defect detector. FIGS. 4 and 5 are side views of the defect detector, FIG. 5 is a perspective view of the light receiver, and FIG. 6 is a plan view of the light receiving surfaces of a plurality of light receivers for transmitted light and transmitted scattered light. FIG. 8 is a block diagram of an electric signal processing circuit. FIGS. 8 to 10 are waveform diagrams for explaining the operation of the electric signal processing circuit. FIG. 11 is a block diagram of a defect data capturing circuit. FIG. 13 is a circuit diagram of the OR unit, FIGS. 13 and 14 are diagrams for explaining the operation of the OR unit, and FIGS. 15 and 16 are diagrams for explaining the operation of the continuity determination unit. FIG. 17 is a diagram showing a format of data output from the defect data acquisition circuit. 1 …… Transparent glass plate 11 …… Scanner 12 …… Receiver 13 …… Photoelectric converter 14 …… Electrical signal processing circuit 15 …… Fault data capture circuit 16 …… Fault identification pattern table 17 …… Information processing device 20 …… Defect detector 21 …… Laser light source 23 …… Rotating polygon mirror 25 …… Parallel mirror 71 …… X axis counter 72 …… OR unit 73 …… Dividing circuit 74 …… Y axis counter 75 …… Continuous judgment section 76 …… FIFO memory 77 …… Defect data compression unit 78 …… X-axis continuous judgment unit 79 …… Y-axis continuous judgment unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Junichi Abe 480 Shimohara, Kamifujisawa, Iruma City, Saitama Prefecture Inside the Tokyo Factory of Yasukawa Electric Co., Ltd. (72) Mitsuo Miyano, Iruma City, Saitama Prefecture Hara 480 Yasukawa Electric Co., Ltd.Tokyo factory

Claims (2)

[Claims] 1. A scanning means for scanning the entire light-transmissive plate material traveling in the length direction with a light spot in the width direction, and at least one of transmitted light, transmitted scattered light, reflected light and reflected scattered light from the light transmissive plate material. Light receiving means having a plurality of light receivers respectively receiving two or more kinds of light, photoelectric conversion means for converting the light received by the plurality of light receivers into an electric signal, and processing an electric signal from the photoelectric conversion means. The electric signal processing means for generating the defect data including information on the kind and the size of the defect, the defect data from the electric signal processing means is taken in, the acquired defect data is combined and processed, and the kind of the defect and At least the defect data capturing means for forming a defect pattern representing the size is compared with the defect identification pattern table that holds the defect pattern from the defect data capturing means in advance, and at least Discriminating defect detecting device of the translucent plate material, characterized in that it comprises an information processing means for identifying the type and size of the. 2. The defect detecting device for identifying a transparent plate material according to claim 1, wherein the defect data capturing circuit captures information indicating a position of the defect on the transparent plate material, and the defect pattern. Position information is added to and output to the identification processing unit, and the identification processing unit identifies the position of the defect based on the position information.