WO2018088423A1

WO2018088423A1 - Optical inspection device

Info

Publication number: WO2018088423A1
Application number: PCT/JP2017/040231
Authority: WO
Inventors: 米澤　良
Original assignee: 株式会社ブイ・テクノロジー
Priority date: 2016-11-09
Filing date: 2017-11-08
Publication date: 2018-05-17
Also published as: CN109804238A; KR102339677B1; JPWO2018088423A1; KR20190082198A; JP6912824B2; CN109804238B

Abstract

The purpose of the present invention is to provide an optical inspection device with which defects can be inspected with a single device and in a single inspection regardless of where on an end surface of an object to be inspected a defect is found. When this optical inspection device images an object to be inspected (G) using a one-dimensional imaging means (13) from substantially vertically above the object to be inspected (G), the optical inspection device irradiates the object to be inspected (G) with light from a plurality of light-emitting units (30a) that are provided in the following: a first region (31) of a substantially semi-cylindrical plane having a central axis (ax) that is located on a central plane (S1), which is a substantially vertical plane that contains the one-dimensional imaging means (13); and in a second region (32) and a third region (33) of a substantially hemispherical or substantially semi-ellipsoidal plane formed at both ends of the first region (31). The light-emitting units (30a) are arrayed in directions that are substantially perpendicular to a conveyance direction (F) of the object to be inspected (G) in the first region (31) except for in a region close to the central plane (S1). In addition, the light-emitting units (30a) are arrayed at positions on the central plane (S1) in the second region (32) and the third region (33).

Description

Optical inspection device

The present invention relates to an optical inspection apparatus.

In Patent Document 1, a plurality of illumination devices are arranged such that light that is irradiated on an object to be inspected and incident on a one-dimensional imaging unit becomes specularly reflected light, diffusely reflected light, and transmitted light, respectively. An imaging optical inspection apparatus that changes the lighting timing for each transfer of the one-dimensional imaging means and accumulates the image data transferred from the one-dimensional imaging means for each image data that is lit by the same illumination device, thereby creating integrated image data Is disclosed.

JP 2012-42297 A

The invention described in Patent Document 1 is for inspecting a transparent plate-shaped inspection object. As a transparent plate-shaped object to be inspected, for example, a cover glass used for a portable terminal or the like can be mentioned. The cover glass has a substantially rectangular shape, and the end surface is polished. In order to inspect defects (for example, chipping of the end face) in end face processing such as cover glass, it is necessary to apply light to all end faces in the same manner and make the reflected light enter the imaging means.

In the invention described in Patent Document 1, the optical axis of the one-dimensional imaging means is inclined by about 45 degrees with respect to the normal line of the inspection object. Therefore, in the invention described in Patent Document 1, light reflected by a part of the end face (referred to as end face I) is incident on the imaging means, but light reflected from an end face other than end face I (referred to as end face II) is imaged. There is a risk of not entering the means. The end face II has a problem that a defect cannot be imaged, that is, the defect cannot be detected.

The present invention has been made in view of such circumstances, and an optical inspection apparatus capable of inspecting a defect with one apparatus and one inspection regardless of the position of the defect on the end face of the non-inspection object. The purpose is to provide.

In order to solve the above-described problems, an optical inspection apparatus according to the present invention includes, for example, a placement unit that places an object to be inspected in a horizontal direction and an object to be inspected placed on the placement unit in the transport direction. A one-dimensional imaging unit configured to image the inspection object from substantially vertically upward, a one-dimensional imaging unit arranged so that a longitudinal direction thereof is substantially orthogonal to the conveyance direction, and the object to be inspected A light irradiating unit having a plurality of light emitting units for irradiating light to the inspection object, and the light irradiating unit has a central axis positioned on a central plane that is a substantially vertical plane including the one-dimensional imaging means. A first region of a semi-cylindrical surface, and a second region and a third region of a substantially hemispherical surface or a substantially semi-elliptical spherical surface formed at both ends of the first region, and in the first region, the conveyance A plurality of band-shaped light emitting portions in which the light emitting portions are arranged along a direction substantially orthogonal to the direction, The band-shaped light emitting portion is provided in a region other than the vicinity of the central surface in the first region, and the light emitting portions are arranged on the central surface in the second region and the third region. To do.

According to the optical inspection apparatus of the present invention, when the inspection object is imaged from the substantially vertical upward direction using the one-dimensional imaging means, the central axis is on the central plane that is the substantially vertical plane including the one-dimensional imaging means. From the first region of the substantially semi-cylindrical surface where the is located, and the plurality of light irradiation portions provided in the second region and the third region of the substantially hemispherical surface or the substantially semi-elliptical spherical surface formed at both ends of the first region Irradiate objects with light. In the first area, the light emitting units are arranged in an area other than the vicinity of the center plane along a direction substantially perpendicular to the conveyance direction of the inspection object. Thereby, the light reflected by the front end surface and the rear end surface of the inspection object can be made incident on the one-dimensional imaging means. In the second region and the third region, the light emitting units are arranged at positions on the center plane. Thereby, the light reflected by the left and right end surfaces of the object to be inspected can be incident on the one-dimensional imaging means. Therefore, regardless of the position of the defect on the end face of the non-inspection object, the defect can be inspected by one apparatus and one inspection.

Here, the belt-like light emitting part is provided so that an optical axis and an intersection line between the central plane and the upper surface of the mounting part intersect, and the belt-like light emitting part includes the optical axis and the central plane. You may have a 1st strip | belt-shaped light emission part whose angle which is made is about 8 degree | times or about 17 degree | times. Thereby, when the pearl pigment is used or when the pearl pigment is not used, it is possible to capture an image in which color unevenness or the like of the printing portion can be detected.

Here, the conveyance unit is controlled so as to convey the inspection object at a constant speed, the one-dimensional imaging unit is driven so as to capture images at a constant interval, and the one-dimensional imaging unit In synchronization with the imaging, a first light emitting region that is a half region divided by the central plane of the first region, a second light emitting region other than the first light emitting region in the first region, the second You may provide the control part which irradiates separately the 3rd light emission area | region on the said center plane of the area | region, the 4th light emission area | region on the said center plane of the said 3rd area | region, and the said 1st strip | belt-shaped light emission part. As a result, an image in which a defect on the front end P surface is lit, an image in which a defect is radiated on the rear end P surface, an image in which a defect is radiated on the left and right end P surfaces, Images can be taken at different timings while the inspection object is conveyed once.

Here, the light irradiation unit may include a cylindrical lens disposed between the belt-like light emitting unit and a line of intersection between the center plane and the upper surface of the mounting unit. Thereby, the light irradiated from the strip | belt-shaped light emission part can be condensed, and the imaging frequency of a one-dimensional imaging means can be made high (imaging time is shortened).

Here, the conveyance unit is controlled so as to convey the inspection object at a constant speed, and a first imaging unit provided above or below the placement unit, and an optical axis of the first imaging unit A first image pickup means and a second image pickup means provided on the opposite side of the mounting portion so as to coincide with the optical axis; and a first coaxial for irradiating the inspection object with parallel light from a normal direction. A first coaxial illumination that is a coaxial illumination of the first imaging means, and a second coaxial illumination that is provided on the opposite side across the first coaxial illumination and the mounting portion, and And the second coaxial illumination that is the coaxial illumination of the two imaging means, and the first imaging means is irradiated with the light irradiated from the first coaxial illumination and specularly reflected by the object to be inspected. The imaging means has light irradiated from the second coaxial illumination and specularly reflected by the inspection object, and the first coaxial Emitted from a light, the light transmitted through the object to be inspected may enter. As a result, a transmission image that can detect defects in the opaque part of the inspection object (for example, scratches on the printed part, chipped printing edges, etc.), specular reflection that can detect scratches and foreign matter on the front and back surfaces of the inspection object An image can be taken.

Here, the first form in which the first coaxial illumination is irradiated with the first intensity, the second form in which the second coaxial illumination is applied with the first intensity, and the first coaxial illumination with the second intensity. Then, the first coaxial illumination or the second coaxial illumination is irradiated with the three irradiation patterns of the third form to be irradiated, and an image is acquired by the first imaging unit in accordance with the irradiation of the first form. The first imaging unit and the second imaging unit acquire an image in accordance with the irradiation of the second form, and acquire an image by the second imaging unit in accordance with the irradiation of the third form. You may provide the 2nd control part which drives a 2nd imaging means. Thereby, a transmission image and a regular reflection image can be taken at different timings while the inspection object is conveyed once.

Here, the second imaging means provided on the opposite side across the mounting portion and the one-dimensional imaging means so that the optical axis coincides with the optical axis of the one-dimensional imaging means, and the inspection object 1st coaxial illumination which irradiates parallel light from a normal line direction, Comprising: The 1st coaxial illumination which is the coaxial illumination of the said one-dimensional imaging means, and the said 1st coaxial illumination and provided in the other side on both sides of the said mounting part A second coaxial illumination that is a coaxial illumination of the second imaging unit, and the light irradiation unit is provided between the one-dimensional imaging unit and the transport unit. The one-dimensional imaging means is irradiated with the light irradiated from the light irradiator or the first coaxial illumination and regularly reflected by the inspection object, and the second imaging means is supplied with the second coaxial illumination. Irradiated and specularly reflected by the object to be inspected, and irradiated from the first coaxial illumination,査物 may enter the light transmitted through the. Thereby, a transmission image that can detect a defect in an opaque portion of the inspection object, and a regular reflection image that can detect a scratch or a foreign object on the front and back surfaces of the inspection object can be captured with fewer imaging means.

Here, the transport unit is controlled so as to transport the inspection object at a constant speed, and the first coaxial illumination is irradiated with the first intensity at the first intensity, and the second coaxial illumination is the first. Irradiating the first coaxial illumination or the second coaxial illumination with three irradiation patterns of the second form irradiating with the intensity of the second, and the third form irradiating the first coaxial illumination with the second intensity, and The image is acquired by the one-dimensional imaging unit in accordance with the irradiation of the first form, the image is acquired by the second imaging unit in accordance with the irradiation of the second form, and is adjusted in accordance with the irradiation of the third form. You may provide the 3rd control part which drives the said one-dimensional imaging means and the said 2nd imaging means so that an image may be acquired with the said 2nd imaging means. Thereby, a transmission image and a regular reflection image can be taken at different timings while the inspection object is conveyed once.

Here, the light irradiation unit may include a light diffusing plate that is provided adjacent to the light emitting unit and diffuses light emitted from the light emitting unit. Thereby, the light irradiated from the several light emission part can be made into an elongate surface light source with a light diffusing plate, and the malfunction that the dotted | punctate light of a light emission part is reflected on to-be-inspected object can be prevented.

Here, a focal length adjustment optical element for adjusting a focal length of the one-dimensional imaging means, and a reflecting mirror provided adjacent to the mounting portion, the focal length adjustment optical element and the reflection are provided. The mirror is provided on the center plane, and in a plan view, a placement area that is an area on the placement portion on which the inspection object is placed is positioned below the one-dimensional imaging unit in the vertical direction. In plan view, the reflecting mirror is provided at a position outside the mounting area and adjacent to the mounting area in a direction substantially orthogonal to the transport direction, and the reflecting surface of the reflecting mirror is substantially flat. And the reflection surface extends substantially along the transport direction so that a line intersecting the center plane is inclined with respect to a horizontal plane, and the optical element for adjusting the focal length includes the one-dimensional imaging unit. Even if it is arranged to overlap the line connecting the reflector There. Thereby, even if it is a cover glass which has a partial cylindrical shape or elliptical cylindrical shape on the side surface, it is possible to inspect for defects on the side surface in one inspection. That is, the image of the side surface of the inspection object is reflected by the reflecting mirror and guided to the one-dimensional imaging means, and the focal length of the one-dimensional imaging means is extended by the optical element for adjusting the focal length. You can focus on the bottom side.

Here, the optical element for adjusting the focal length is a glass plate, and may be provided so that both end faces substantially orthogonal to the plate thickness direction are horizontal. Accordingly, light is refracted in the process of entering the focal length adjusting optical element and in the process of emitting the light from the focal length adjusting optical element, and the focal position of the one-dimensional imaging unit can be extended.

Here, the moving unit that moves the one-dimensional imaging unit in the vertical direction, the height acquiring unit that acquires the height of the inspection object, and the moving unit based on the information acquired by the height acquiring unit A movement control unit that controls and moves the one-dimensional imaging unit in a vertical direction in accordance with a height change of the inspection object passing under the one-dimensional imaging unit. As a result, even when the height of the object to be inspected changes, a sharp image in focus can be picked up by the one-dimensional image pickup means.

Here, the height acquisition unit includes a surface light source that emits light in a direction substantially orthogonal to the transport direction, a side surface imaging unit that receives light that has been irradiated from the surface light source and passed through the inspection object, You may have. As a result, the height of the object to be inspected can be accurately obtained by capturing an image such as a shadow image in which the light is blocked by the object to be inspected and the other part being bright. .

Here, the light irradiation unit includes a light emitting block in which the light emitting units are arranged in a row in the second region and the third region, a second cylindrical lens through which light emitted from the light emitting unit passes, In the second region and the third region, the extending direction of the light emitting block is inclined with respect to the horizontal direction, and in the second region and the third region, the light emitting block extends. The extending direction of the second cylindrical lens may be inclined with respect to the installation direction. Thereby, the focus of the light irradiated from the 2nd field and the 3rd field can be matched with a to-be-inspected object. In addition, the second region and the third region can supplement the first region, and the number of light emitting units included in the band-like light emitting unit in the first region can be reduced.

Here, the light irradiation unit may include a heat radiating member formed of a material having high thermal conductivity, and the light emitting unit may be provided on the heat radiating member. Thereby, the heat generated from the light emitting unit can be efficiently radiated.

Here, the heat dissipation member includes a blower that sends air to the heat dissipation member, and the heat dissipation member includes a plurality of plates on which the light emitting unit is provided, and the plate extends in a direction substantially orthogonal to the transport direction. And the said ventilation part may send the wind of the direction along the extending direction of the said plate. Thereby, the cooling effect by a heat radiating member can be improved.

Here, the second imaging unit is provided below the placement unit, a circular polarizing filter is provided above the second imaging unit, and the circular polarizing filter is substantially orthogonal to the thickness direction. The plane in the direction to be inclined may be provided so as to be slightly inclined with respect to the direction substantially orthogonal to the optical axis of the second imaging means. Thereby, the light reflected by the surface of the imaging lens of the second imaging means provided on the lower side of the mounting unit is incident on the camera provided on the upper side of the mounting unit, and the image captured by this camera is bright. It is possible to prevent light lines from being included.

According to the present invention, the defect can be inspected with one apparatus and one inspection regardless of the position of the end face of the non-inspection object.

It is a front view which shows the outline of the optical inspection apparatus 1 which concerns on 1st Embodiment. 3 is a diagram showing details of the three-dimensional illumination unit 30. FIG. It is a schematic diagram which shows the detail of the strip | belt-shaped light emission part 31a. It is a figure which shows typically the cross section of the optical inspection apparatus 1 when the optical inspection apparatus 1 is cut | disconnected by the surface parallel to xz plane so that the 1st area | region 31 may be included. 3 is a schematic plan view of a three-dimensional illumination unit 30. FIG. It is a schematic diagram which shows the detail of the strip | belt-shaped light emission part 32a. 2 is a block diagram showing an electrical configuration of the optical inspection apparatus 1. FIG. 4 is a block diagram for explaining electrical connection between an output unit 73 and each component of the optical inspection apparatus 1. FIG. It is a figure explaining the signal output to the 1st camera 11, the 2nd camera 12, and the coaxial illumination part 20 from the output part 73. FIG. 10 is a timing chart in the process shown in FIG. 9. It is a figure explaining the signal output to the 3rd camera 13 and the three-dimensional illumination part 30 from the output part 73. FIG. It is a figure which shows a response | compatibility with the signal output shown in FIG. 11, and the defect contained in the image imaged by the three-dimensional illumination part 30. FIG. It is a figure which shows the mode of the light in the end surface of the cover glass G, and shows the path | route of light with a dashed-two dotted line. 12 is a timing chart in the processing shown in FIG. 11. It is an example of the transmission image of the cover glass G. It is an example of the regular reflection image of the cover glass G. It is an example of the image (partial enlarged view) which the defect in the P inner surface of the front-end | tip of the cover glass G shined. It is an example of the image (partial enlarged view) in which the defect of the printing part of the cover glass G is darker than another printing part. It is a figure which shows typically the light emission block 30b-1 concerning a modification, (A) is a side view, (B) is the figure which looked at the state shown to (A) from the downward direction in the figure. It is a front view which shows the outline of the optical inspection apparatus 2 which concerns on 2nd Embodiment. It is a figure which shows a response | compatibility with the order of an imaging process, and the image imaged with the 1st camera 11 and the 2nd camera 12. FIG. It is a front view which shows the outline of the optical inspection apparatus 3 which concerns on 3rd Embodiment. It is the perspective view which expanded and displayed a part of optical inspection apparatus 3. FIG. It is a figure which shows schematic structure in the state which cut | disconnected the optical inspection apparatus 3 by center plane S1. It is a figure which shows the relationship between the position of the cover glass G1, and the image imaged with the 3rd camera 13, (A) is an enlarged view of the side part of the cover glass G1, (B) is imaged with the 3rd camera 13. A part of the image to be displayed is shown. It is a figure which shows a mode that the height of cover glass G1 is measured, and is the figure seen from the direction substantially orthogonal to the conveyance direction F. FIG. It is a figure which shows a mode that the height of cover glass G1 is measured, and is the figure seen along the conveyance direction F. FIG. It is a perspective view which shows the outline of the three-dimensional illumination part 30A with which the optical inspection apparatus which concerns on 3rd Embodiment is provided. FIG. 4 is a schematic diagram showing details of a band-shaped light emitting unit 31a-1. FIG. 6 is a schematic diagram showing details of a band-shaped light emitting unit 32a-1. It is a figure explaining the path | route of the light irradiated from three-dimensional illumination part 30A. It is a front view which shows the outline of the optical inspection apparatus 5 which concerns on 5th Embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same elements are denoted by the same reference numerals, and the description of overlapping parts is omitted.

The present invention is an optical inspection apparatus for inspecting a cover glass G of a portable terminal or the like that is an object to be inspected. Based on the image captured by the optical inspection device, it is possible to inspect defects such as scratches and uneven polishing on the end surface, front surface, and back surface of the cover glass G, and defects such as uneven printing and chipping on the portion printed on the cover glass G. It is. In the present embodiment, an example in which the optical inspection apparatus inspects the cover glass G of the mobile terminal or the like is illustrated, but the inspection object inspected by the optical inspection apparatus is not limited to the cover glass.

The cover glass G is polished so that the entire circumference is a curved surface. Further, the back surface of the cover glass G is partially printed. Hereinafter, the circular arc-shaped polished surface of the peripheral surface is referred to as a polished surface (hereinafter referred to as P surface). In addition, the printed portion of the cover glass G is a monochromatic print in which a monochromatic organic paint is applied, or a transparent pigment containing a pearl pigment in which a monochromatic pigment as a base color is applied and translucent particles are covered with transparent titanium dioxide or the like. Pearl coating is applied in which layers are applied in layers.

<First Embodiment>
FIG. 1 is a front view showing an outline of an optical inspection apparatus 1 according to the first embodiment. The optical inspection apparatus 1 mainly includes an imaging unit 10, a coaxial illumination unit 20, a three-dimensional illumination unit 30, a placement unit 40, and a transport unit 50 (see FIG. 8).

The mounting unit 40 includes a plurality of rollers 40a, and a cover glass G is mounted on the upper side. The conveyance part 50 moves the cover glass G provided in the mounting part 40 to the conveyance direction F (here, x direction), for example, has an actuator (not shown) etc. which rotate the roller 40a. Since the mounting part 40 and the conveyance part 50 are already well-known, description is abbreviate | omitted.

The imaging unit 10 mainly includes a first camera 11, a second camera 12, a third camera 13 (in the present embodiment, the first imaging unit, the second imaging unit, and the primary, respectively, of the present invention). Original imaging means). The first camera 11, the second camera 12, and the third camera 13 mainly include

imaging lenses

11a, 12a, and 13a, and

line sensors

11b, 12b, and 13b such as line CCD and CMOS. The

line sensors

11b, 12b, and 13b are arranged so that the longitudinal direction is substantially orthogonal to the transport direction F of the cover glass G (that is, along the y direction). Since the imaging unit 10 is already known, a description thereof will be omitted.

The first camera 11 is provided on the upper side (+ z side) of the placement unit 40, and images the cover glass G from substantially vertically upward (+ z direction). The second camera 12 is provided on the opposite side (the lower side (−z side) of the mounting unit 40) across the first camera 11 and the mounting unit 40, and the cover glass G faces substantially vertically downward (−z direction). Take an image from The first camera 11 and the second camera 12 are provided so that the optical axes oax coincide.

The third camera 13 is provided on the upper side (+ z side) of the placement unit 40, and images the cover glass G from substantially vertically upward. The third camera 13 is arranged so that the position in the horizontal direction (position in a plane parallel to the xy plane) is different from that of the first camera 11 and the second camera 12.

The coaxial illumination unit 20 includes an upper coaxial illumination 21 that is the coaxial illumination of the first camera 11 and a lower coaxial illumination 22 that is the coaxial illumination of the second camera 12. The upper coaxial illumination 21 and the lower coaxial illumination 22 are so-called Koehler illuminations, and irradiate the cover glass G with parallel light from the normal direction (z direction). The upper coaxial illumination 21 and the lower coaxial illumination 22 are opposite to each other with the mounting portion 40 therebetween so that the optical axes oax coincide (the upper coaxial illumination 21 is the + z side of the mounting portion 40, and the lower coaxial illumination 22 is It is provided on the −z side of the mounting portion 40.

The configuration of the upper coaxial illumination 21 and the lower coaxial illumination 22 will be described. The upper coaxial illumination 21 and the lower coaxial illumination 22 are the

light sources

21a and 22a, the

glass integrators

21b and 22b that uniformize the illuminance distribution, the

condenser lenses

21c and 22c, and the

condenser lenses

21c and 22c, respectively.

Apertures

21d and 22d provided at positions substantially coincident with the focal point,

collimator lenses

21e and 22e that convert light into parallel light, mirrors 21f and 22f that bend the optical path, and parallel linear grooves, and linearly align the light. It has

Fresnel lenses

21g and 22g that condense on top, and half mirrors 21h and 22h that bend the optical path.

The

light sources

21a and 22a have a light emitting member surface-mounted on a metal plate such as aluminum. A heat radiating plate (heat sink) is provided on the back surface of the metal plate. The light emitting member is a white LED (for example, a color temperature of 5700 K), and its irradiation angle is about 120 degrees.

The

light sources

21a and 22a and the

integrators

21b and 22b are provided adjacent to each other. Since light is emitted from the LED in a relatively wide area, some light leaks without being incident on the

integrators

21b and 22b, but most of the light is incident on the

integrators

21b and 22b and enters the cover glass G. Irradiated.

The half mirror 21 h is provided on the optical axis of the first camera 11. Therefore, the light reflected by the half mirror 21 h is irradiated perpendicularly to the cover glass G, and the light regularly reflected by the cover glass G enters the first camera 11. In addition, the light reflected by the half mirror 21 h passes through the cover glass G and enters the second camera 12.

The half mirror 22h is provided on the optical axis of the second camera 12. Therefore, the light reflected by the half mirror 22h is irradiated perpendicularly to the cover glass G, and the light regularly reflected by the cover glass G enters the second camera 12.

The three-dimensional illumination unit 30 irradiates light to the cover glass G from a plurality of directions. The light emitted from the three-dimensional illumination unit 30 and reflected by the cover glass G enters the third camera 13. FIG. 2 is a diagram illustrating details of the three-dimensional illumination unit 30. In FIG. 2, the third camera 13 (the imaging lens 13 a and the line sensor 13 b) is indicated by a dotted line, and the visual field position 13 c of the third camera 13 and the light path to the third camera 13 are indicated by a two-dot chain line.

The three-dimensional illumination unit 30 includes a first region 31 having a substantially semi-cylindrical surface, and a second region 32 and a third region 33 having a substantially hemispherical surface or a substantially semi-elliptical spherical surface. The second region 32 and the third region 33 have the same shape and are disposed at both ends of the first region 31.

In the first region 31, the light emitting unit 30a is provided on a substantially semi-cylindrical surface. The light emitting unit 30a is similar to the

light sources

21a and 22a, and includes a white LED and a heat dissipation member. The central axis ax of the first region 31 is located on the central plane S 1 that is a substantially vertical plane including the third camera 13.

In the second region 32 and the third region 33, the light emitting unit 30a is provided on a substantially hemispherical surface or a substantially semielliptical spherical surface. The center points of the second region 32 and the third region 33 are located on the center plane S1. In the present embodiment, the second region 32 and the third region 33 are substantially hemispherical surfaces, but the shape of the second region 32 and the third region 33 is not limited to this.

In the first region 31, the light emitting unit is disposed between the third camera 13 and the placement unit 40, that is, in a region other than the vicinity of the center plane S 1 along a direction substantially orthogonal to the transport direction F (that is, the y direction). 30a are arranged. The light emitting sections 30a arranged along the y direction are assumed to be strip-shaped

light emitting sections

31a, 31b, 31c, 32d, 31e, 31f, 31g (detailed later). In the present embodiment, the ten strip-shaped light emitting sections 31a to 31j (see FIG. 4) are provided, but the number of strip-shaped light emitting sections is not limited to this.

FIG. 3 is a schematic diagram showing details of the strip-shaped light emitting portion 31a. Since the belt-like light emitting portions 31a to 31j have the same configuration, only the belt-like light emitting portion 31a will be described, and the description of the belt-like light emitting portions 31b to 31j is omitted.

The belt-like light emitting portion 31a has a total length of 3L, and has three light emitting blocks 30b in which the light emitting portions 30a are arranged in a row so that the length in the longitudinal direction is L.

The light emitting unit 30a has a lateral width w of about 3.4 mm and a length h of about 3.4 mm, and the distance between adjacent light emitting units 30a is about 0.2 mm. In the present embodiment, since the length L of the light emitting block 30b is approximately 50 mm, about 13 light emitting units 30a are arranged in one light emitting block 30b. Thereby, the strip-shaped (line-shaped) light is emitted from the strip-shaped light emitting portion 31a.

In the present embodiment, a white LED is used as the light emitting unit 30a, but the light emitting unit 30a is not limited to the white LED. The light emitting unit 30a is, for example, one of a combination of a blue or ultraviolet LED and a yellow phosphor, a combination of red, green and blue three-color chips, or a combination of a blue LED and red and green fluorescent agents. May be used.

Next, the arrangement of the strip light emitting units 31a to 31j in the three-dimensional illumination unit 30 will be described. FIG. 4 is a diagram schematically showing a cross section of the optical inspection apparatus 1 when the optical inspection apparatus 1 is cut along a plane parallel to the xz plane so as to include the first region 31. In FIG. 4, the path of light emitted from the band-like light emitting portions 31a to 31j is indicated by a two-dot chain line.

The central axis ax of the first region 31 is located in the vicinity of the upper surface of the cover glass G, and the belt-like light emitting portions 31a to 31j are provided on the circumference of the radius R centered on the central axis ax (see the dotted line in FIG. 4). It is done. In addition, since the thickness of the cover glass G is very small, the position of the upper surface of the cover glass G substantially coincides with the line of intersection between the center plane S1 and the upper surface of the mounting portion 40 (not shown in FIG. 4). The radius R is substantially the same as the length 3L of the band-like light emitting portions 31a to 31j.

In the belt-like light emitting portions 31a to 31j, the optical axis (see the alternate long and short dash line in FIG. 4) is an intersection line between the center plane S1 and the mounting portion 40 (intersection line between the center plane S1 and the cover glass G), that is, the center axis ax. Provided to intersect.

The band-like light emitting portions 31a to 31e are located on the + x side from the central plane S1, and the band-like light emitting portions 31f to 31j are located on the −x side from the central plane S1.

The belt-like

light emitting portions

31a and 31f are provided at positions closest to the center plane S1. An angle θ1 formed by the optical axis of the band-shaped

light emitting portions

31a and 31f and the center plane S1 is approximately 8 degrees.

The strip-shaped

light emitting portions

31b and 31g are provided outside the strip-shaped

light emitting portions

31a and 31f and adjacent to the strip-shaped

light emitting portions

31a and 31f. An angle θ2 formed by the optical axis of the band-shaped

light emitting portions

31b and 31g and the center plane S1 is approximately 17 degrees.

The strip-shaped

light emitting portions

31c and 31h are provided outside the strip-shaped

light emitting portions

31b and 31g and adjacent to the strip-shaped

light emitting portions

31b and 31g. An angle θ3 formed by the optical axis of the band-shaped

light emitting portions

31c and 31h and the center plane S1 is approximately 26 degrees.

The strip-shaped

light emitting portions

31d and 31i are provided outside the strip-shaped

light emitting portions

31c and 31h and adjacent to the strip-shaped

light emitting portions

31c and 31h. An angle θ4 formed by the optical axis of the band-shaped

light emitting portions

31d and 31i and the center plane S1 is approximately 35 degrees.

The strip

light emitting portions

31e and 31j are provided outside the strip

light emitting portions

31d and 31i and adjacent to the strip

light emitting portions

31d and 31i. An angle θ5 formed by the optical axis of the belt-like

light emitting portions

31e and 31j and the center plane S1 is approximately 44 degrees.

The belt-like light emitting portions 31a to 31j have a cylindrical lens 30c provided on the optical axis. The cylindrical lens 30c is formed by, for example, cutting an acrylic bar along the central axis and polishing the cut surface. The cylindrical lens 30c is provided between the light emitting unit 30a and the central axis ax, and condenses light emitted from the light emitting unit 30a in the vicinity of the central axis ax.

FIG. 5 is a schematic plan view of the three-dimensional illumination unit 30. In FIG. 5, the visual field position 13c of the third camera 13 is indicated by a dotted line. In FIG. 5, the light emitting block 30 d (detailed later) is indicated by a broken line.

The second region 32 and the third region 33 have strip-like light emitting portions 32a to 32i and 33a to 33i in which the light emitting portions 30a are arranged in a line. In the present embodiment, each of the nine strip-like light emitting portions 32a to 32i and 33a to 33i is provided, but the number of the strip-like light emitting portions is not limited to this.

The strip-like

light emitting portions

32a and 33a are provided on the center plane S1. The strip-shaped light emitting portions 32b to 32e and 33b to 33e are provided on the extended lines of the strip-shaped light emitting portions 31a to 31d, respectively. The strip-shaped light emitting portions 32f to 32i and 33f to 33i are provided on the extended lines of the strip-shaped light emitting portions 31f to 31i, respectively.

FIG. 6 is a schematic diagram showing details of the band-like light emitting part 32a. Since the belt-like light emitting portions 32a to 32i and 33a to 33i have substantially the same configuration, only the belt-like light emitting portion 32a will be described, and description of the belt-like light emitting portions 32b to 32i and 33a to 33i will be omitted.

The strip-shaped light emitting unit 32a includes a plurality of light emitting blocks 30d in which the light emitting units 30a are arranged in a line. In the present embodiment, since the length l of the light emitting block 30d is approximately 18.5 mm and the distance between the adjacent light emitting units 30a is approximately 0.2 mm, five light emitting units 30a are included in one light emitting block 30d. About to be arranged. The light emitting blocks 30d are arranged adjacent to each other so that the light emitting portion 30a is positioned on a substantially cylindrical surface having a radius R (see the dotted line in FIG. 6).

Returning to the explanation of FIG. The number of light emitting blocks 30d in the belt-like light emitting portions 32a to 32c, 32f, 32g, 33a to 33c, 33f, and 33g is five, and the number of light emitting blocks 30d in the belt-like

light emitting portions

32d, 32h, 33d, and 33h is four. Yes, the number of light emitting blocks 30d in the band-like

light emitting units

32e, 32i, 33e, 33i is two, but the number of light emitting blocks 30d in the band-like light emitting units 32a to 32i, 33a to 33i is not limited to this.

The optical axis of each light-emitting block 30d in the strip-shaped light-emitting

portions

32a and 33a faces the center points O2 and O3 of the second region 32 and the third region 33. The optical axis of each light emitting block 30d in the band-like light emitting portions 32b to 32i and 33a to 33i is directed to the center point O1 of the first region 31. However, the direction of the optical axis of each light-emitting block 30d in the strip-shaped light-emitting portions 32a to 32i and 33a to 33i is not limited to the form shown in FIG.

FIG. 7 is a block diagram showing an electrical configuration of the optical inspection apparatus 1. The optical inspection apparatus 1 includes an integrated circuit 71, an input unit 72, an output unit 73, a power supply unit 74, and a communication interface (I / F) 75.

The integrated circuit 71 is, for example, a field-programmable gate array (FPGA), and operates based on a program to control each unit. The integrated circuit 71 has a function of a control unit (including the control unit and the second control unit of the present invention) that controls each unit of the optical inspection apparatus 1. Specifically, the integrated circuit 71 acquires signals from the input unit 72, the output unit 73, and the like, and generates a signal to be output from the output unit 73 based on the acquired signals. In the present embodiment, the FPGA that is the integrated circuit 71 stores a program for realizing each function. However, the integrated circuit 71 is not limited to the FPGA, and the execution method of the program is not limited to this.

The input unit 72 receives signals from various sensors such as the

position detection sensors

81 and 82. The input unit 72 includes switches for setting the output mode of each channel of the output unit 73, setting the imaging frequency of the imaging unit 10, and the like.

The output unit 73 has a plurality of channels, and outputs from different channels to the imaging unit 10, the coaxial illumination unit 20, the stereoscopic illumination unit 30, and the like. For example, the output unit 73 outputs a drive motor pulse to the transport unit 50 and outputs a horizontal synchronization signal, a vertical synchronization signal, and the like to the imaging unit 10. In addition, the output unit 73 is an LED that indicates an error display such as a communication error or a timeout, the cover glass G is running, the capture unit 10 is waiting for capture, the coaxial illumination unit 20 or the three-dimensional illumination unit 30 is illuminating, or the like. And the like.

FIG. 8 is a block diagram illustrating the electrical connection between the output unit 73 and each component of the optical inspection apparatus 1. The output unit 73 includes an imaging unit 10 (first camera 11, second camera 12, and third camera 13), a coaxial illumination unit 20 (upper coaxial illumination 21 and lower coaxial illumination 22), and a three-dimensional illumination unit 30 (band-shaped). Signals are output to the light emitting units 31a to 31j, 32a to 32i, 33a to 33i) and the transport unit 50.

The signal output from the output unit 73 is generated by the integrated circuit 71 based on a horizontal synchronization signal or the like input from the personal computer (PC) 100 via the communication I / F 75.

Returning to the explanation of FIG. The power supply unit 74 receives, for example, a voltage of 100 VAC and includes a switching power supply that converts the voltage into a necessary voltage. The power supply unit 74 supplies power to the coaxial illumination unit 20 and the three-dimensional illumination unit 30.

The communication I / F 75 receives data from an external device and transmits the data to the integrated circuit 71, and transmits data generated by the integrated circuit 71 to other devices. The communication I / F 75 has a connector for programming and debugging the integrated circuit 71. The communication I / F 75 acquires a horizontal synchronization signal, a vertical synchronization signal, a drive motor start signal, and the like from the PC 100 and outputs them to the integrated circuit 71. The communication I / F 75 outputs image data captured by the imaging unit 10 to the PC 100 or the like.

Position detection sensors

81 and 82 detect the position of the cover glass G. The position detection sensor 81 detects that the cover glass G has been transported under the first camera 11 and the second camera 12 and has passed under the first camera 11 and the second camera 12. The position detection sensor 82 detects that the cover glass G has been transported under the third camera 13 and has passed under the third camera 13.

The PC 100 includes a central processing unit (CPU) 101, a random access memory (RAM) 102, a read only memory (ROM) 103, an input / output interface (I / F) 104, a communication interface (I / F) 105, and the like. A media interface (I / F) 106.

The CPU 101 operates based on programs stored in the RAM 102 and the ROM 103, and controls each unit. A signal output from the CPU 101 is output to the optical inspection apparatus 1 via the communication I / F 105.

The RAM 102 is a volatile memory. The RAM 102 stores programs executed by the CPU 101, data used by the CPU 101, and the like. The ROM 103 is a non-volatile memory that stores various control programs and the like. The CPU 101 operates based on programs stored in the RAM 102 and the ROM 103, and controls each unit. The ROM 103 stores a boot program executed by the CPU 101 when the PC 100 is started up, a program depending on the hardware of the PC 100, and the like.

The CPU 101 controls the input device 111 such as a keyboard and a mouse and the output device 112 such as a display device via the input / output I / F 104. The CPU 101 acquires data from the optical inspection apparatus 1 and other devices via a network or the like via the communication I / F 105 and outputs the generated data to the optical inspection apparatus 1.

Based on the input from the input device 111, the CPU 101 sets the output of the channel of the output unit 73, the order of output of the lighting signal in the integrated circuit 71, the loop setting of the processing, the cover glass G from the edge detection to the start of imaging. Various settings such as setting of the G travel distance (idle travel distance) are performed, and these setting data are generated. The communication I / F 105 outputs the setting data generated by the CPU 101 to the optical inspection device 1. In addition, the CPU 101 acquires an image captured by the imaging unit 10 from the optical inspection device 1 and generates an image for inspection. Details of the image generation process will be described later.

The media I / F 106 reads the program or data stored in the storage medium 113 and stores it in the RAM 102. Note that the storage medium 113 is, for example, an IC card, an SD card, a DVD, or the like.

In addition, the program which implement | achieves each function is read from the storage medium 113, for example, is installed in the optical inspection apparatus 1 via RAM102, and is performed by CPU101.

The configurations of the optical inspection apparatus 1 and the PC 100 illustrated in FIG. 7 are the main configurations for describing the features of the present embodiment, and do not exclude, for example, configurations included in a general information processing apparatus. The constituent elements of the optical inspection apparatus 1 may be classified into more constituent elements according to the processing content, or one constituent element may execute processing of a plurality of constituent elements. In FIG. 7, the optical inspection apparatus 1 and the PC 100 are separate apparatuses, but the components of the PC 100 may be included in the optical inspection apparatus 1.

Processing performed by the optical inspection apparatus 1 configured as described above will be described. The following processing is mainly performed in the integrated circuit 71.

The integrated circuit 71 generates a drive motor pulse for driving the roller 40 a of the placement unit 40, and the output unit 73 outputs this to the transport unit 50. Thereby, the cover glass G moves on the mounting part 40 along the conveyance direction F at a constant speed.

When it is detected from the position detection sensor 81 that the cover glass G has been conveyed under the first camera 11 and the second camera 12, a detection signal is input from the position detection sensor 81 to the integrated circuit 71 via the input unit 72. Is done. When this detection signal is input, the integrated circuit 71 starts processing for capturing a transmission image and a regular reflection image with the first camera 11 and the second camera 12. Hereinafter, processing for capturing a transmission image and a regular reflection image will be described with reference to FIGS.

<Process for capturing a transmission image and a regular reflection image>
FIG. 9 is a diagram illustrating signals output from the output unit 73 to the first camera 11, the second camera 12, and the coaxial illumination unit 20. Channels (hereinafter referred to as “ch”) are a part of channels of the output unit 73, ch 1 to 3 are outputs to the upper coaxial illumination 21, and ch 4 to 6 are outputs to the lower coaxial illumination 22. ROOP is a signal indicating repetitive processing and is output to the integrated circuit 71. Note that the numerical values described in ch1 to ch6 in FIG. 9 are times for irradiating the upper coaxial illumination 21 and the lower coaxial illumination 22, and the unit is μsec (microseconds).

FIG. 10 is a timing chart in the process shown in FIG. The imaging signal is a signal for driving the first camera 11 and the second camera 12, and is generated in the integrated circuit 71 based on a horizontal synchronization signal input at a constant period. In the present embodiment, the frequency of the imaging signal is 3 kHz, and the interval T of the imaging signal is approximately 330 μsec. The imaging signal is a signal in which the imaging period T1 is High and the blanking period T2 is Low. By adjusting the imaging period T1, the light amount of the first camera 11 and the second camera 12 (brightness of the image to be captured). Adjust. The coaxial illumination signal is generated in synchronization with the imaging signal. In the present embodiment, the imaging period T1 is 300 μsec, but the imaging period T1 is not limited to this.

In the following, the processing in order 1 to 3 shown in FIGS. 9 and 10 will be described in detail.
(Order 1) The integrated circuit 71 generates a signal for irradiating the upper coaxial illumination 21 at 5 μsec, and the output unit 73 outputs this signal to the upper coaxial illumination 21. At the same time, the integrated circuit 71 generates an imaging signal, and the output unit 73 outputs it to the second camera 12. As a result, light transmitted through the cover glass G enters the second camera 12, and a transmitted image is captured by the second camera 12. In the transmission image, it is possible to detect a defect in an opaque portion, for example, a scratch on a printed portion, a lack of a printed edge, or the like.

In order 1, the signal for irradiating the upper coaxial illumination 21 becomes High at the same time as the imaging signal becomes High, and becomes Low after 5 μsec. The time of 5 μsec for irradiating the upper coaxial illumination 21 is much shorter than the imaging period of 300 μsec. In glass, about 4% of light is reflected and the remaining 96% of light is transmitted. Therefore, a transmission image with appropriate brightness can be taken by shortening the time for irradiating the upper coaxial illumination 21.

In order 1, the upper coaxial illumination 21 was irradiated at 5 μsec and the transmission image was captured by the second camera 12, but the lower coaxial illumination 22 was irradiated at 5 μsec and the transmission image was captured by the first camera 11. May be.

(Order 2) The integrated circuit 71 generates a signal for irradiating the upper coaxial illumination 21 at 100 μsec, and the output unit 73 outputs this signal to the upper coaxial illumination 21. At the same time, the integrated circuit 71 generates an imaging signal, and the output unit 73 outputs this to the first camera 11. As a result, the light regularly reflected by the surface of the cover glass G enters the first camera 11, and a regular reflection image is captured by the first camera 11.

The upper coaxial illumination 21 irradiates light to the cover glass G from the vertical direction. Therefore, a portion where there is no scratch or foreign matter on the surface of the cover glass G is reflected brightly in the captured image because the light is regularly reflected and enters the first camera 11. On the other hand, the portion where the surface of the cover glass G has scratches, foreign matters, etc. is reflected darkly in the captured image because the light is irregularly reflected and does not enter the first camera 11. In this way, scratches, foreign matters, etc. on the surface of the cover glass G can be detected. It should be noted that the detection of surface scratches, foreign matters, and the like with specularly reflected light is effective only for high reflectance such as mirror surfaces.

(Order 3) The integrated circuit 71 generates a signal for irradiating the lower coaxial illumination 22 at 100 μsec, and the output unit 73 outputs this signal to the lower coaxial illumination 22. At the same time, the integrated circuit 71 generates an imaging signal, and the output unit 73 outputs it to the second camera 12. Thereby, the light regularly reflected by the back surface of the cover glass G enters the second camera 12, and a reflected image is captured by the second camera 12. In this way, scratches, foreign matters, etc. on the back surface of the cover glass G can be detected.

In addition, the integrated circuit 71 generates a signal indicating repetition processing at the same time as performing output in order 3. The output unit 73 outputs a signal indicating repetition processing to the integrated circuit 71 simultaneously with outputting a signal to the lower coaxial illumination 22. The integrated circuit 71 receives the signal indicating the repetition process, returns the process to the beginning, and repeats the process of sequentially outputting the signals shown in the order 1 to 3.

In

order

2 and 3, the signal for irradiating the upper coaxial illumination 21 and the lower coaxial illumination 22 becomes High at the same time as the imaging signal becomes High, and becomes Low after 100 μsec has elapsed. The time of 100 μsec for irradiating the upper coaxial illumination 21 in order 2 and the lower coaxial illumination 22 in order 3 is about 1/3 of the imaging period T1 (300 μsec), which is significantly larger than the irradiation time in order 1 (5 μsec). Long. As described above, when capturing a regular reflection image, it is possible to capture a reflection image with appropriate brightness by increasing the time for irradiating the upper coaxial illumination 21 and the lower coaxial illumination 22.

The integrated circuit 71 outputs a drive motor pulse to the transport unit 50 via the output unit 73 simultaneously with the signal output of the irradiation patterns in the order 1 to 3 described above. As a result, the cover glass G is transported at a constant speed on the mounting portion 40 and the positions of the cover glass G and the first camera 11 and the second camera 12 are relatively changed, while the first camera 11 or the first camera Imaging is performed by the two cameras 12.

This allows the transmission image and the regular reflection image to be taken at different timings while the object to be inspected is transported once. The process of capturing the transmission image and the specular reflection image of the cover glass G with the first camera 11 and the second camera 12 continues until the cover glass G has passed through the first camera 11 and the second camera 12. When the cover glass G has passed through the first camera 11 and the second camera 12, a detection signal from the position detection sensor 81 is input to the integrated circuit 71. When this detection signal is input, the integrated circuit 71 ends the signal output to the first camera 11, the second camera 12, and the coaxial illumination unit 20.

The integrated circuit 71 continuously outputs drive motor pulses to the transport unit 50 via the output unit 73. When the position detection sensor 82 detects that the cover glass G is conveyed under the third camera 13, a detection signal is input from the position detection sensor 82 to the integrated circuit 71 via the input unit 72. When this detection signal is input, the integrated circuit 71 starts a process of capturing the reflected image with the third camera 13. Hereinafter, processing for capturing a reflection image will be described with reference to FIGS.

<Process for capturing a reflected image>
FIG. 11 is a diagram for describing signals output from the output unit 73 to the third camera 13 and the stereoscopic illumination unit 30. The channels 11 to 46 are part of the channels that the output unit 73 has. The numerical values described in ch 11 to 46 are the time for irradiating the three-dimensional illumination unit 30, and the unit is μsec. In FIG. 11, illustration of some of the channels is omitted. FIG. 12 is a diagram illustrating the correspondence between the signal output illustrated in FIG. 11 and the defects included in the image captured by the third camera 13. FIG. 13 is a diagram showing the state of light on the end face of the cover glass G, and the light path is indicated by a two-dot chain line. FIG. 14 is a timing chart in the processing shown in FIG.

In FIG. 11, ch11 to ch40 are outputs to the band-like light emitting sections 31a to 31j. In the present embodiment, one channel is assigned to each light emitting block 30b. For example, ch11 to 13 are outputs to the strip-shaped light emitting section 31a (three light-emitting blocks 30d constituting the same, the same applies hereinafter), ch14 to 16 are outputs to the strip-shaped light emitting section 31b, and ch17 to 19 are strip-shaped. Outputs to the light emitting unit 31c, ch20 to 22 are outputs to the strip light emitting unit 31d, ch23 to 25 are outputs to the strip light emitting unit 31e, and ch26 to 28 are outputs to the strip light emitting unit 31f. , Ch29 to 31 are outputs to the strip light emitting portion 31g, ch32 to 34 are outputs to the strip light emitting portion 31h, ch35 to 37 are outputs to the strip light emitting portion 31i, and ch38 to 40 are strip light emitting portions. This is an output to 31j.

Further, ch41 is an output to the strip-shaped light emitting section 32a, ch42 is an output to the strip-shaped light emitting sections 32b to 32e, and ch43 is an output to the strip-shaped light emitting sections 32f to 32i. Further, ch44 is an output to the strip-shaped light emitting section 33a, ch45 is an output to the strip-shaped light emitting sections 33b to 33e, and ch46 is an output to the strip-shaped light emitting sections 33f to 33i.

Hereinafter, processes in order 1 to 9 shown in FIGS. 11 and 13 will be described in detail.
(Sequence 1) The integrated circuit 71 generates signals for irradiating the band-shaped light emitting portion 31f at 100 μsec, the band-shaped light emitting portion 31g at 120 μsec, the band-shaped light emitting portion 31h at 150 μsec, the band-shaped light emitting portion 31i at 180 μsec, and the band-shaped light emitting portion 31j at 210 μsec. The output unit 73 outputs this signal to the band-like light emitting units 31f to 31j (see FIG. 11). At the same time, the integrated circuit 71 generates an imaging signal, and the output unit 73 outputs this to the third camera 13. As a result, the third camera 13 is irradiated with light that is irradiated from the −x direction and reflected from the inner surface (hereinafter referred to as “P inner surface”) of the P surface of the front end (+ x side end) of the cover glass G (see FIG. 13). What is imaged by the third camera 13 in order 1 is an image in which defects (printing unevenness, polishing unevenness, scratches, etc.) on the P inner surface of the front end of the cover glass G shine (see FIG. 12).

(Order 2) When the printed part of the cover glass G is pearl-coated, the integrated circuit 71 generates a signal for irradiating the strip-shaped light emitting portion 31b at 300 μsec and the strip-shaped light emitting portion 31g at 300 μsec, and outputs the output unit 73. Outputs this signal to the strip-like

light emitting portions

31b and 31g (see FIG. 11). At the same time, the integrated circuit 71 generates an imaging signal, and the output unit 73 outputs this to the third camera 13. As a result, light that is irradiated from the + x direction 17 ° and the −x direction 17 ° and reflected by the printing portion of the cover glass G enters the third camera 13.

When the printed portion of the cover glass G is printed other than pearl paint (single color printing or the like), the integrated circuit 71 outputs a signal for irradiating the strip-shaped light emitting portion 31a at 300 μsec and the strip-shaped light emitting portion 31f at 300 μsec. The output unit 73 generates this signal and outputs the signal to the strip

light emitting units

31a and 31f. At the same time, the integrated circuit 71 generates an imaging signal, and the output unit 73 outputs this to the third camera 13. As a result, light that is irradiated from the + x direction 8 ° and the −x direction 8 ° and reflected by the printing part of the cover glass G enters the third camera 13.

The image captured by the third camera 13 in order 2 is that the defect (color unevenness, etc.) of the printing part of the cover glass G is different from the other printing part (for example, the defect of the printing part is different from the other printing part). A dark or bright image) (see FIG. 12).

(Sequence 3) The integrated circuit 71 generates a signal for irradiating the strip light emitting portion 31a at 100 μsec, the strip light emitting portion 31b at 120 μsec, the strip light emitting portion 31c at 150 μsec, the strip light emitting portion 31d at 180 μsec, and the strip light emitting portion 31e at 210 μsec. The output unit 73 outputs this signal to the band-like light emitting units 31a to 31e (see FIG. 11). At the same time, the integrated circuit 71 generates an imaging signal, and the output unit 73 outputs this to the third camera 13. As a result, the third camera 13 is irradiated with light that is irradiated from the + x direction and reflected by the inner surface P of the rear end (−x side end) of the cover glass G (see FIG. 13). What is imaged by the third camera 13 in order 3 is an image in which defects on the P inner surface at the rear end of the cover glass G are lit (see FIG. 12).

(Order 4) The integrated circuit 71 generates a signal for irradiating the band-shaped light emitting unit 32a at 200 μsec, and the output unit 73 outputs this signal to the band-shaped light emitting unit 32a (see FIG. 11). At the same time, the integrated circuit 71 generates an imaging signal, and the output unit 73 outputs this to the third camera 13. As a result, the third camera 13 is irradiated with light irradiated from the −y direction and reflected from the P inner surface at the left end (+ y side end) of the cover glass G. What is imaged by the third camera 13 in order 4 is an image in which a defect on the inner surface P at the left end of the cover glass G is lit (see FIG. 12).

(Sequence 5) The integrated circuit 71 generates a signal for irradiating the band-shaped

light emitting units

33a, 33f to 33i, and 31f to 31j at 3 μsec, and the output unit 73 outputs this signal to the band-shaped

light emitting units

33a, 33f to 33i, 31f to It outputs to 31j (refer FIG. 11). At the same time, the integrated circuit 71 generates an imaging signal, and the output unit 73 outputs this to the third camera 13. As a result, the third camera 13 is irradiated from the + y direction and between the + y direction and the −x direction, and is reflected on the front side of the P surface on the left end and the left rear end side of the cover glass G (hereinafter referred to as the P surface). Is incident (see FIG. 13). The image captured by the third camera 13 in order 5 is an image in which defects on the P surface on the left end and the left rear end side of the cover glass G are reflected (see FIG. 12). In this image, most defects such as scratches and foreign matters on the P surface appear dark.

(Order 6) The integrated circuit 71 generates a signal for irradiating the strip-shaped light emitting sections 33b to 33e at 3 μsec, and the output section 73 outputs this signal to the strip-shaped light emitting sections 33b to 33e (see FIG. 11). At the same time, the integrated circuit 71 generates an imaging signal, and the output unit 73 outputs this to the third camera 13. As a result, the third camera 13 is irradiated with light that is irradiated from between the + y direction and the + x direction and reflected from the left end of the cover glass G on the P surface on the front end side. The image captured by the third camera 13 in order 6 is an image in which defects on the P surface on the front end side from the left end of the cover glass G are reflected (see FIG. 12).

(Order 7) The integrated circuit 71 generates a signal for irradiating the band-shaped light emitting unit 33a at 200 μsec, and the output unit 73 outputs this signal to the band-shaped light emitting unit 33a (see FIG. 11). At the same time, the integrated circuit 71 generates an imaging signal, and the output unit 73 outputs this to the third camera 13. As a result, light that is irradiated from the + y direction and reflected by the P inner surface at the right end (−y side end) of the cover glass G enters the third camera 13. What is imaged by the third camera 13 in order 7 is an image in which a defect on the P inner surface at the right end of the cover glass G shines (see FIG. 12).

(Sequence 8) The integrated circuit 71 generates a signal for irradiating the strip light emitting sections 32f to 32i at 3 μsec, and the output section 73 outputs this signal to the strip light emitting sections 32f to 32i (see FIG. 11). At the same time, the integrated circuit 71 generates an imaging signal, and the output unit 73 outputs this to the third camera 13. As a result, the third camera 13 is irradiated with light which is irradiated from between the −y direction and the −x direction and reflected from the P surface on the rear end side from the right end of the cover glass G. The image captured by the third camera 13 in order 8 is an image in which defects on the P surface on the rear end side from the right end of the cover glass G are reflected (see FIG. 12).

(Sequence 9) The integrated circuit 71 generates a signal for irradiating the strip light emitting units 32a to 32e and 31a to 31e at 3 μsec, and the output unit 73 outputs the signal to the strip light emitting units 32a to 32e and 31a to 31e. (See FIG. 11). At the same time, the integrated circuit 71 generates an imaging signal, and the output unit 73 outputs this to the third camera 13. Thereby, the third camera 13 is irradiated with light that is irradiated from the −y direction and between the −y direction and the + x direction and reflected from the right end of the cover glass G on the P surface on the right end side. What is imaged by the third camera 13 in order 9 is an image in which defects on the P surface on the right end and right tip side of the cover glass G are reflected (see FIG. 12).

Further, the integrated circuit 71 generates a signal indicating repetition processing at the same time as performing output in order 9, and the output unit 73 outputs a signal indicating repetition processing to the integrated circuit 71. The integrated circuit 71 receives the signal indicating the repetition process, returns the process to the beginning, and repeats the process of sequentially outputting the signals shown in order 1 to 9.

Here, when inspecting the P inner surfaces at the left end and the right end in the

order

4 and 7, respectively, the strip-like

light emitting portions

32a and 33a are much longer than when inspecting the P surface in the

order

5, 6, 8, and 9. Irradiate. Therefore, in

order

4 and 7, the third camera 13 captures a saturated image in which the P surface of the cover glass G shines white.

In addition, the order 1 to 9 shown in FIGS. 11 and 12 is an example, and the order of examination parts and examination contents can be arbitrarily determined. Further, the inspection of the inner surface P at the front end of the cover glass G shown in order 1 and the inspection of the P surface from the left end to the front end side of the cover glass G shown in order 6 are unnecessary at the center part and the rear end part of the cover glass G. In addition, the inspection of the P inner surface at the rear end of the cover glass G shown in order 3 and the inspection of the P surface from the right end to the rear end side of the cover glass G shown in order 8 are performed at the front end portion and the central portion of the cover glass G. It is unnecessary. The integrated circuit 71 calculates the number of drive motor pulses from the information indicating the length of the cover glass G, obtains the position of the cover glass G based on the output drive motor pulse number, and in order 1 according to the position of the cover glass G. 3, 6, and 8 may be omitted.

FIG. 14 is a timing chart in the processing shown in FIG. For order 1, only the signal irradiated at 100 μsec is displayed. The imaging signal is the same as that shown in FIG. The signal for irradiating the three-dimensional illumination unit 30 becomes High at the same time as the imaging signal becomes High, and becomes Low after the irradiation time elapses.

Note that the required amount of light is about 1: 100 when the light reflected by the P surface is incident on the third camera 13 and when the light reflected by the printing unit is incident on the third camera 13. Therefore, the irradiation time of the three-dimensional illumination unit 30 is made different between the case where the light reflected by the P surface is incident on the third camera 13 and the case where the light reflected by the printing unit is incident on the third camera 13.

The integrated circuit 71 outputs a drive motor pulse to the transport unit 50 via the output unit 73 simultaneously with the output of the signals in the order 1 to 9. As a result, the third camera 13 captures an image while the cover glass G is transported at a constant speed on the placement unit 40 and the positions of the cover glass G and the third camera 13 are relatively changed.

As a result, an image in which a defect on the front end P surface is shined, an image in which a defect on the rear end P surface is shined, an image in which a defect on the left and right end P surfaces is shining, While the glass G is conveyed once, it can be photographed at different timings. The process of capturing the transmitted image and the specular image of the cover glass G with the third camera 13 continues until the cover glass G finishes passing through the third camera 13. When the cover glass G has passed through the third camera 13, a detection signal from the position detection sensor 82 is input to the integrated circuit 71. When this detection signal is input, the integrated circuit 71 ends the signal output to the third camera 13 and the stereoscopic illumination unit 30.

Thereafter, the integrated circuit 71 outputs a drive motor pulse to the transport unit 50 by a predetermined number of pulses, and moves the cover glass G to the processing end position. Then, the integrated circuit 71 ends a series of processes.

When the series of processing is completed, images captured by the first camera 11, the second camera 12, and the third camera 13 are output to the PC 100 via the output unit 73. The CPU 101 generates an inspection image from images captured by the first camera 11, the second camera 12, and the third camera 13. In the present embodiment, the CPU 101 extracts images picked up with the same illumination pattern from the images picked up by the first camera 11, the second camera 12, and the third camera 13, and connects them to obtain a plane. Generate an image. Hereinafter, the image generation process will be described.

The CPU 101 generates a transmission image and a regular reflection image from images captured by the first camera 11 and the second camera 12. In the process of capturing a transmission image and a specular reflection image, irradiation of irradiation patterns in order 1 to 3 is repeated as shown in FIGS. Therefore, the CPU 101 extracts every third frame (the first frame, the fourth frame,...) From the image captured by the second camera 12 with the first frame as a reference, and connects these images. A two-dimensional image is generated. Thereby, a transmission image (planar image) of the cover glass G is generated. As shown in FIG. 15, the transmission image is an image in which an opaque printed portion appears dark, and a defective printing portion (dotted circle in FIG. 15) can be confirmed.

Further, the CPU 101 extracts every third frame (second frame, fifth frame,...) From the second frame of the image captured by the first camera 11, and connects these images. A two-dimensional image is generated. Thereby, an upper regular reflection image, that is, a regular reflection image (planar image) on the surface of the cover glass G is generated. As shown in FIG. 16, the regular reflection image is an image in which a portion without a defect (a scratch is illustrated in FIG. 16) is bright and a scratch is dark. Even if the scratch overlaps with the printed portion, the reflectance on the glass surface is higher than that of the printed portion, so that the scratch appears darker than the other portions.

Further, the CPU 101 extracts every third frame (third frame, sixth frame,...) From the third frame of the image captured by the second camera 12 and connects these images. A two-dimensional image is generated. Thereby, a lower regular reflection image, that is, a regular reflection image (planar image) on the back surface of the cover glass G is generated.

Further, the CPU 101 generates a reflection image from the image captured by the third camera 13. In the process of capturing a reflected image, irradiation of irradiation patterns 1 to 9 is repeated as shown in FIGS. Therefore, the CPU 101 extracts every nine frames (the first frame, the tenth frame,...) Of the images captured by the third camera 13 with the first frame as a reference, and connects these images. A two-dimensional image is generated. Thereby, as shown in FIG. 17, a planar image of the cover glass G in which the defect on the inner surface P at the tip of the cover glass G is lit is generated.

The CPU 101 extracts every nine frames (second frame, eleventh frame,...) From the second frame of the image captured by the third camera 13, and connects these images to form a two-dimensional image. Generate an image of Thereby, as shown in FIG. 18, the plane image of the cover glass G in which the defect of the printing part of the cover glass G appeared darker than other printing parts is produced | generated.
For the sake of explanation, FIGS. 17 and 18 show an enlarged part of the planar image and display a black line around the defect.

The CPU 101 extracts every nine frames (third frame, twelfth frame,...) Of the images captured by the third camera 13 with reference to the third frame, and connects these images to form a two-dimensional image. Generate an image of Thereby, the planar image of the cover glass G in which the defect in the P inner surface of the rear end of the cover glass G shines is produced | generated.

The CPU 101 extracts every nine frames (fourth frame, thirteenth frame,...) From the fourth frame of the image captured by the third camera 13 and connects these images to form a two-dimensional image. Generate an image of Thereby, the plane image of the cover glass G in which the defect in the P inner surface of the left end of the cover glass G shined was produced | generated.

The CPU 101 extracts every nine frames (fifth frame, fourteenth frame,...) Out of the images captured by the third camera 13 with reference to the fifth frame, and connects these images to form a two-dimensional image. Generate an image of Thereby, the plane image of the cover glass G in which the defect in the P surface of the left end of the cover glass G and the rear end side was reflected is produced | generated.

The CPU 101 extracts every nine frames (sixth frame, fifteenth frame,...) Out of the images captured by the third camera 13 with reference to the sixth frame, and connects these images to form a two-dimensional image. Generate an image of Thereby, the planar image of the cover glass G in which the defect in the P surface of the front end side from the left end of the cover glass G was reflected is produced | generated.

The CPU 101 extracts every nine frames (7th frame, 16th frame,...) From the 7th frame of the image captured by the third camera 13, and connects these images to form a two-dimensional image. Generate an image of Thereby, the planar image of the cover glass G in which the defect in the P inner surface of the right end of the cover glass G was shining is produced | generated.

The CPU 101 extracts every 9 frames (8th frame, 17th frame,...) From the 8th frame of the image captured by the third camera 13, and connects these images to form a two-dimensional image. Generate an image of Thereby, the planar image of the cover glass G in which the defect in the P surface on the rear end side from the right end of the cover glass G is reflected is generated.

The CPU 101 extracts every nine frames (9th frame, 18th frame,...) From the 9th frame of the image captured by the third camera 13 and connects these images to form a two-dimensional image. Generate an image of Thereby, the planar image of the cover glass G in which the defect in the P surface of the right end and front end side of the cover glass G was reflected is produced | generated.

According to the present embodiment, since the image is captured by irradiating the cover glass G with light from various directions using the three-dimensional illumination unit 30, no matter where the defect is on the end surface of the cover glass G, A single optical inspection apparatus 1 can be used to inspect defects in a single inspection.

In particular, in the first region 31, the light emitting portions 30a are arranged along the y direction in a region other than the vicinity of the center plane S1. Therefore, it is possible to irradiate the cover glass G with the band-shaped light and inspect the region in the vicinity of the central axis ax in the same manner regardless of the position in the y direction.

In addition, since the plurality of strip-like light emitting portions 31a to 31j are provided, it is possible to irradiate light in the vicinity of the central axis ax from various angles. In order to capture the entire image of the defect on the P plane, it is important to irradiate light simultaneously from a light source whose angle between the optical axis and the center plane S1 is about 8 degrees to a light source that is about 44 degrees. Therefore, in order to capture the entire image of the defect on the P surface at the front end or the rear end, it is important to include a plurality of strip-like light emitting portions 31a to 31j. In the second region 32 and the third region 33, since the strip-like

light emitting portions

32a and 33a are provided at positions on the center plane S1, it is possible to capture the entire image of the defect on the left and right P surfaces. .

Further, according to the present embodiment, the band-like

light emitting portions

31b and 31g are arranged so that the angle θ2 formed by the optical axis and the center plane S1 is approximately 17 degrees, and when the light is reflected by pearl printing. By capturing the scattered light with the third camera 13, it is possible to capture an image in which the defect contrast is greater than the gloss of the pearl material.

For example, when the images are taken with the belt-like

light emitting portions

31a and 31f in which the angle θ1 between the optical axis and the center plane S1 is about 8 degrees, the gloss of the pearl material is reflected strongly. Further, for example, when imaging is performed with the strip-shaped

light emitting portions

31c and 31h in which the angle θ3 formed between the optical axis and the center plane S1 is approximately 26 degrees, or the angle θ4 formed between the optical axis and the center plane S1 is approximately 35 degrees. When imaging is performed with the band-shaped

light emitting portions

31d and 31i, the contrast of the defective portion of the pearl coating is reduced.

On the other hand, by irradiating the cover glass G with light from an angle of 17 degrees with respect to the normal direction as in the present embodiment, the contrast of the defective part of the pearl paint is low or high with respect to the other parts. The resulting image can be taken, and the gloss of the pearl material is less likely to reach the threshold for defect detection. Therefore, it is possible to easily detect a pearl coating defect based on the captured image.

Further, according to the present embodiment, the strip-like

light emitting portions

31a and 31f are arranged so that the angle θ1 formed by the optical axis and the center plane S1 is about 8 degrees, and the angle θ1 is 8 degrees with respect to the normal direction. By irradiating the cover glass G with light from an angle, it is possible to capture an image in which the contrast of the defective portion of monochromatic printing is lower or higher than the other portions.

Further, in the present embodiment, the amount of light can be varied depending on the contents of imaging by changing the irradiation time of light from the coaxial illumination unit 20 and the three-dimensional illumination unit 30 without changing the imaging time of the imaging unit 10.

Further, in the present embodiment, a three-dimensional illumination unit 30 is provided corresponding to the third camera 13, and an image captured with the same irradiation pattern is extracted from the images captured with the third camera 13, and each irradiation pattern is extracted. By generating different plane images, an image equivalent to imaging using a plurality of cameras can be realized with the minimum number of cameras.

In the present embodiment, since the optical inspection apparatus 1 includes both the band-like

light emitting parts

31a and 31f and the band-like

light emitting parts

31b and 31g, when the pearl pigment is used in the same apparatus, the pearl pigment is not used. In any case, it is possible to capture an image in which color unevenness or the like of the printing unit can be detected.

In the present embodiment, the angle θ1 formed by the optical axis of the belt-like

light emitting portions

31a and 31f and the center plane S1 is approximately 8 degrees, but the angle θ1 may be approximately 8 to 10 degrees. Further, the angles θ2 to θ5 are not limited to the illustrated angles.

In the present embodiment, the defect detection image is generated by the PC 100. However, the defect of the cover glass G may be detected by the PC 100 based on the generated image. For example, in the image shown in FIG. 14, a defect can be detected by comparing a pixel value with a threshold value. For example, for the image shown in FIG. 15, a defect can be detected by calculating an average value of a plurality of pixels and comparing the average value with a threshold value.

In this embodiment, the cylindrical lens 30c is provided on the optical axis of the band-like light emitting portions 31a to 31j. However, the cylindrical lens 30c is not essential. However, when the cylindrical lens 30c is provided, the light emitted from the light emitting unit 30a by the cylindrical lens 30c can be condensed near the central axis ax, and thereby the amount of light directed to the third camera 13 can be increased. . Therefore, the imaging frequency of the imaging unit 10 can be increased (imaging time is shortened).

In the present embodiment, as shown in FIG. 11, the strip-shaped

light emitting portions

32a, 32b to 32e, and 32f to 32i are connected to different channels, and the strip-shaped

light emitting portions

33a, 33b to 33e, and 33f to 33i are respectively different. Although connected to the channel, the relationship between the band-like light emitting portions 32a to 32i and 33a to 33i and the channel is not limited to this. For example, the band-like light emitting units 32b to 32i and 33b to 33i may be connected to one channel, or the band-like light emitting units 32a to 32i and 33a to 33i may be connected to different channels.

Moreover, in this Embodiment, although the irradiation time in each irradiation pattern shown to FIG. 9, 10, 11, 13 was shown, irradiation time is an illustration and irradiation time is limited to the value described in these. is not. In each of the irradiation patterns shown in FIGS. 9, 10, 11, and 13, the irradiation time is specified in μsec. However, the irradiation time may be specified as a ratio to the imaging time.

In the present embodiment, the light emitting units 30a have the

light emitting blocks

30b and 30d arranged in a line, but the

light emitting blocks

30b and 30d may have a light diffusion plate. 19 is a diagram schematically showing a light emitting block 30b-1 according to a modified example, FIG. 19A is a side view, and FIG. 19B is a diagram illustrating the state shown in FIG. It is the figure seen from the downward direction in (A).

The light emitting block 30b-1 is provided with a lenticular lens 30e, which is a light diffusing plate, adjacent to the light emitting portion 30a. The lenticular lens 30e is provided so as to cover the plurality of light emitting units 30a. The lenticular lens 30e is formed by arranging a large number of elongated convex lenses having a semi-cylindrical cross section at an equal pitch, and diffuses light components in the same direction as the convex lens arrangement direction (a direction perpendicular to the longitudinal direction of the convex lenses). In the light emitting block 30b-1, the arrangement direction of the convex lenses and the light emitting unit 30a are the same. Therefore, the light emitted from the light emitting unit 30a is diffused by the lenticular lens 30e, and the light emitted from the plurality of light emitting units 30a can be used as one elongated surface light source by the lenticular lens 30e.

For example, when the lenticular lens 30e is not provided, when the inspection is performed based on the light regularly reflected by the front end P surface and the rear end P surface of the cover glass G, the light emitting unit 30a is formed on the front end P surface and the rear end P surface. Although dot-like light may be reflected, the occurrence of such a problem can be prevented by providing the lenticular lens 30e so as to cover the light emitting portion 30a.

For inspection of the tip P surface and the rear end P surface, the band-like light emitting portion 31b and the band-like light emitting portion 31g are weakly illuminated, and the light from the band-like light emitting portion 31b and the band-like light emitting portion 31g is reflected on the tip P surface and the rear end P surface. It is possible to use a method to At this time, if the belt-like

light emitting portions

31b and 31g do not have the lenticular lens 30e, dot-like light is reflected on the front end P surface and the rear end P surface, and the inspection cannot be performed well. On the other hand, when the lenticular lens 30e is provided in the belt-like

light emitting portions

31b and 31g, since point-like light is reflected on the front end P surface and the rear end P surface, the front end P depends on whether or not this light is bent. It is possible to inspect defects related to the polishing of the surface and the rear end P surface.

In FIG. 19, one lenticular lens 30e is provided in one light emitting block 30b-1, but the number of lenticular lenses 30e is not limited to this. A plurality of lenticular lenses arranged may be provided so as to cover the plurality of light emitting units 30a. The light diffusion plate is not limited to a lenticular lens.

<Second Embodiment>
In the first embodiment of the present invention, an image using coaxial illumination and an image using stereoscopic illumination are captured by different cameras, but an image using coaxial illumination and an image using stereoscopic illumination are taken. May be taken with the same camera.

The second embodiment of the present invention is a mode in which imaging is performed with two cameras. Hereinafter, the optical inspection apparatus 2 according to the second embodiment will be described. In addition, about the part same as the optical inspection apparatus 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

FIG. 20 is a front view showing an outline of the optical inspection apparatus 2 according to the second embodiment. The optical inspection apparatus 2 mainly includes an imaging unit 10A, a coaxial illumination unit 20, a stereoscopic illumination unit 30, a placement unit 40, and a conveyance unit 50 (not shown).

The imaging unit 10A includes a first camera 11 (corresponding to the one-dimensional imaging unit of the present invention in the present embodiment) and a second camera 12 (corresponding to the second imaging unit of the present invention). The arrangement of the first camera 11 and the second camera 12 is the same as that of the optical inspection apparatus 1.

The three-dimensional illumination unit 30 is provided between the first camera 11 and the placement unit 40. The three-dimensional illumination unit 30 is provided at a position where the central axis ax intersects the optical axis of the first camera 11. Since the angle θ1 (see FIG. 4) formed by the optical axis of the strip-shaped

light emitting portions

31a and 31f and the center plane S1 is approximately 8 degrees, the light from the upper coaxial illumination 21 is not blocked by the three-dimensional illumination unit 30.

The processing performed by the optical inspection apparatus 2 configured as described above will be described. The integrated circuit 71 (including the third control unit of the present invention) generates a drive motor pulse for driving the roller 40 a of the mounting unit 40, and the output unit 73 outputs this to the transport unit 50. Thereby, the cover glass G moves on the mounting part 40 along the conveyance direction F at a constant speed.

When it is detected from the position detection sensor 81 that the cover glass G has been conveyed under the first camera 11 and the second camera 12, a detection signal is input from the position detection sensor 81 to the integrated circuit 71 via the input unit 72. Is done. When this detection signal is input, the integrated circuit 71 starts processing for capturing a reflected image with the first camera 11 and processing for capturing a transmitted image and a regular reflected image with the first camera 11 and the second camera 12.

FIG. 21 is a diagram illustrating the correspondence between the order of the imaging processing and the images captured by the first camera 11 and the second camera 12.

Processing for capturing a reflected image with the first camera 11 (processing in order 1 to 9 in FIG. 21) is performed in the optical inspection apparatus 1 except that the imaging signal generated by the integrated circuit 71 is output to the first camera 11. Since this is the same as the processing (FIGS. 11, 12, and 14), detailed description is omitted.

The integrated circuit 71 starts the process of capturing the transmission image and the regular reflection image shown in the order 10 to 12 when the processes in the order 1 to 9 are completed. Since the processes shown in the order 10 to 12 are the same as the processes shown in FIGS. 9 and 10 (the processes in the order 1 to 3), detailed description thereof is omitted.

The integrated circuit 71 outputs in order 12 and at the same time generates a signal indicating repetitive processing and outputs the signal to the integrated circuit 71 via the output unit 73. The integrated circuit 71 receives the signal indicating the repetition process, returns the process to the beginning, and repeats the process of sequentially outputting the signals shown in the order 1 to 12.

According to the present embodiment, it is possible to inspect a defect by one inspection using one optical inspection apparatus 2. Further, it is possible to capture a reflected image, a transmitted image, and a regular reflection image with a minimum (two) cameras.

In the present embodiment, since the half mirror 21h is provided on the optical axis of the first camera 11, the amount of light emitted from the three-dimensional illumination unit 30 and incident on the first camera 11 is determined by the optical inspection apparatus 1. The amount of light that is irradiated from the three-dimensional illumination unit 30 and is incident on the third camera 13 is approximately half. Therefore, it is desirable to brighten the light emitted from the three-dimensional illumination unit 30. In the present embodiment, since the number of images captured by the first camera 11 is larger than that in the first embodiment, the light emitted from the three-dimensional illumination unit 30 can be brightened and the imaging frequency can be increased. desirable.

<Third Embodiment>
In the first embodiment of the present invention, the cover glass G in which the arc-shaped P surface is formed is inspected, but the form of the cover glass is not limited to this. Recently, the curved surface around the cover glass has become deeper, and a cover glass in which the curved surface portion has a partial cylindrical shape or an elliptical cylindrical shape has been used.

The third embodiment of the present invention is a mode for inspecting a cover glass having a partial cylindrical shape or an elliptical cylindrical shape around it. Hereinafter, an optical inspection apparatus 3 according to the third embodiment will be described. In addition, about the part same as the optical inspection apparatus 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

FIG. 22 is a front view showing an outline of the optical inspection apparatus 3 according to the third embodiment. The optical inspection apparatus 3 mainly includes an imaging unit 10, a coaxial illumination unit 20, a three-dimensional illumination unit 30, a placement unit 40, a transport unit 50 (not shown), a side inspection unit 60, and a height acquisition unit. 90.

FIG. 23 is an enlarged perspective view of a part of the optical inspection device 3. The side surface inspection unit 60 mainly includes focal length adjusting

optical elements

61 and 62 and reflecting

mirrors

63 and 64. The focal length adjusting

optical elements

61 and 62 and the reflecting mirrors 63 and 64 are located on a substantially vertical center plane S1 including the third camera 13.

The focal length adjusting

optical elements

61 and 62 are optical elements for adjusting the focal length of the third camera 13. In the present embodiment, thick glass plates are used as the focal length adjusting

optical elements

61 and 62. The focal length adjusting

optical elements

61 and 62 are provided such that both end faces substantially orthogonal to the plate thickness direction are horizontal.

The focal length adjustment optical element 61 and the focal length adjustment optical element 62 have substantially the same positions in the x direction and the z direction, and face each other with a line ax1 passing through the center of the third camera 13 extending in the z direction. It is provided as follows. Further, the focal length adjustment

optical elements

61 and 62 are provided on the upper side (+ z side) of the stereoscopic illumination unit 30.

The reflecting mirrors 63 and 64 are members that reflect the image on the side surface of the cover glass G1 and guide it to the third camera 13. The reflecting mirrors 63 and 64 are substantially plate-shaped and are provided adjacent to the placement unit 40. In the present embodiment, it is provided between adjacent rollers 40a.

The positions of the reflecting mirror 63 and the reflecting mirror 64 are substantially the same in the x direction and the z direction, and are provided so as to face each other with a line ax1 passing through the center of the third camera 13 extending in the z direction. Further, in plan view, the reflecting mirror 63 and the reflecting mirror 64 are respectively provided at positions outside the placement area and adjacent to the placement area in a direction substantially orthogonal to the transport direction F. Here, the placement area is an area on the placement portion 40 where the cover glass G 1 is placed, and includes an area on the lower side in the vertical direction of the third camera 13. FIG. 23 illustrates a state where the cover glass G1 is placed on the placement area.

FIG. 24 is a diagram showing a schematic configuration in a state in which the optical inspection device 3 is cut along the center plane S1. FIG. 24 shows a state viewed from the downstream side in the transport direction F (+ x direction). A two-dot chain line in FIG. 24 schematically shows a path of light incident on the third camera 13.

The reflecting surfaces 63a and 64a of the reflecting mirrors 63 and 64 are substantially flat, and the conveying direction is such that a line intersecting the center plane S1 (a line indicating the reflecting

surfaces

63a and 64a in FIG. 24) is inclined with respect to the horizontal plane. It extends substantially along F.

On the central plane S1, the reflecting mirror 63 and the reflecting mirror 64 are respectively located on both sides of the cover glass G1. The cover glass G 1 has a plane Ga parallel to the horizontal direction and a side surface Gb inclined with respect to the horizontal direction in a state of being placed on the placement unit 40. The side surface Gb has a partial cylindrical shape or an elliptical cylindrical shape, and the inclination of the side surface Gb with respect to the horizontal direction is approximately 30 to 45 degrees. Further, the ends Ge of the side surfaces Gb on both sides are placed on the roller 40a.

The image of the plane Ga is guided to the imaging lens 13a without passing through the focal length adjusting

optical elements

61 and 62. In other words, the focal length adjusting

optical elements

61 and 62 do not exist on the line connecting the imaging lens 13a and the plane Ga.

On the other hand, the image of the side surface Gb is reflected by the reflecting

surfaces

63a and 64a, passes through the focal length adjusting

optical elements

61 and 62, and is guided to the imaging lens 13a. In other words, the focal length adjusting

optical elements

61 and 62 are arranged so as to overlap with a line connecting the imaging lens 13a and the reflecting

surfaces

63a and 64a.

In the present embodiment, the focal length adjustment

optical elements

61 and 62 are partially cut away so that the focal length adjustment

optical elements

61 and 62 are not positioned on the line connecting the imaging lens 13a and the plane Ga. It is missing.

The focal position F1 when not passing through the focal length adjusting

optical elements

61 and 62 is the position of the plane Ga of the cover glass G1. The plate thickness of the cover glass G1 is approximately 0.5 mm, and the focal position F1 is preferably located near the center of the plane Ga in the plate thickness direction.

When the light passes through the focal length adjustment

optical elements

61 and 62, the light enters the focal length adjustment

optical elements

61 and 62 and the light exits from the focal length adjustment

optical elements

61 and 62. Is refracted, the focal position F2 is farther than the focal position F1. The extension of the focal position by passing through the focal length adjusting optical elements 61 and 62 (see the black arrow in FIG. 24) is that the plate pressure of the focal length adjusting

optical elements

61 and 62 is T, and the refractive index of the glass is n. Then, it can be expressed as TT / n. For example, if T is 12 mm and n is 1.5, the focal position extends 4 mm by passing through the focal length adjusting

optical elements

61 and 62. That is, the focal position F2 is located on the −z side by 4 mm from the focal position F1.

FIG. 25 is a diagram illustrating the relationship between the position of the cover glass G1 and an image captured by the third camera 13, (A) is an enlarged view of a side surface portion of the cover glass G1, and (B) is a third view. A part of the image captured by the camera 13 is shown. In FIG. 25A, the reflecting surface 63a is indicated by a dotted line, and the path of light reflected by the reflecting surface 63a and incident on the third camera 13 is indicated by a two-dot chain line.

With respect to the partial area (area I) near the plane Ga of the cover glass G1 and the side surface Gb of the cover glass G1, the image does not pass through the focal length adjustment

optical elements

61 and 62, and the imaging lens 13a. Led to. Since the focal position F1 is at the position of the plane Ga, the image of the region I is a sharp image. The image on the side surface Gb is a blurred image with little focus (see the shaded portion in FIG. 25).

The images of the side surface Gb and a partial region (region II) of the plane Ga near the side surface Gb are reflected by the reflecting surface 63a (the same applies to the reflecting surface 64a) and guided to the imaging lens 13a. Therefore, the image of the region II is reversed left and right, the image of the end Ge of the side surface Gb is on the inside, and the image on the plane Ga side of the side surface Gb is on the outside.

Further, the image of the region II passes through the focal length adjustment

optical elements

61 and 62 and is guided to the imaging lens 13a. Since the focal position F2 is positioned below the focal position F1 by passing through the focal length adjusting

optical elements

61 and 62, the majority of the side surface Gb is a sharp image with focus. In the present embodiment, by making the depth of focus of the third camera 13 and the height of the side surface Gb substantially coincide with each other, it is possible to obtain a sharp image focused on the entire side surface Gb. Further, the boundary portion between the plane Ga and the side surface Gb is a blurred image with little focus (see the shaded portion in FIG. 25). Note that the most central side of the image in the region II is a portion where the cover glass G1 is not present, and the third camera 13 captures a black image.

It is desirable to set area I and area II so that they partially overlap. As a result, two images, an image that has passed through the focal length adjustment

optical elements

61 and 62 and an image that has not passed through, can be obtained at the boundary between the plane Ga and the side surface Gb, so that one of the images is in focus. Even if not, it is possible to detect a defect in the boundary portion between the plane Ga and the side surface Gb.

Returning to the explanation of FIG. The optical inspection apparatus 3 includes a height acquisition unit 90 that acquires the height of the cover glass G1. The height acquisition unit 90 is provided on the upstream side (−x side) in the transport direction F with respect to the side surface inspection unit 60, and mainly includes a surface light source 91, a camera 92, and a reflecting mirror 93.

26 and 27 are diagrams schematically illustrating how the height of the cover glass G1 is measured, and FIG. 26 is a diagram viewed from a direction substantially orthogonal to the transport direction F (here, the −y direction). FIG. 27 is a view taken along the transport direction F (here, the + x direction). A two-dot chain line in FIG. 27 indicates a path of light emitted from the surface light source 91.

The surface light source 91, the camera 92, and the reflecting mirror 93 are provided with the placement unit 40 interposed therebetween. The surface light source 91 irradiates light in a direction substantially perpendicular to the transport direction F (here, the + y direction). The camera 92 is irradiated from the surface light source 91, passes through the cover glass G1, and is reflected by the reflecting mirror 93. As a result, in the camera 92, an image such as a shadow picture is obtained where the portion where the light is blocked by the cover glass G1 is dark and the other portion is bright. Therefore, the height of the cover glass G1 can be obtained accurately. Note that the reflecting mirror 93 is not essential, and the light emitted from the surface light source 91 and passing through the cover glass G 1 may be incident on the camera 92.

The front end Gc and the rear end Gd of the cover glass G1 are lower than the plane Ga. Therefore, by illuminating light in the y direction from the surface light source 91 while moving the cover glass G1 in the transport direction F by the placement unit 40, the light passing through the cover glass G1 is imaged by the camera 92, and the front end Gc and the rear The height change of the end Gd can be acquired.

Returning to the explanation of FIG. The third camera 13 is provided with a moving unit 95 that moves the third camera 13 in the vertical direction. The moving unit 95 includes an actuator (not shown) that is a drive source, and a moving mechanism (not shown) that moves the third camera 13 in the vertical direction by transmitting the driving of the actuator. Various known techniques such as a feed screw can be used for the moving mechanism.

The CPU 101 (see FIG. 7) controls the moving unit 95 based on the image captured by the camera 92, and moves the third camera 13 in the vertical direction in accordance with the height change of the front end Gc and the rear end Gd. The ROM 103 (see FIG. 7) stores the number of pulses for sending the cover glass G1 in the transport direction F until the cover glass G1 is positioned directly below the third camera 13 after being imaged by the camera 92. Further, the ROM 103 stores the relationship between the driving amount of the actuator and the moving amount of the third camera 13. The CPU 101 drives the actuator of the moving unit 95 based on the information stored in the ROM 103 to move the third camera 13 in the vertical direction in accordance with the height change of the cover glass G1 passing under the third camera 13. Move.

According to the present embodiment, the focal length of the third camera 13 is extended using the focal length adjusting

optical elements

61 and 62, and the light incident on the third camera 13 is reflected using the reflecting mirrors 63 and 64. Thus, even for the cover glass G1 having the side surface Gb, the defect of the side surface Gb can be inspected by one inspection.

Moreover, according to this Embodiment, it can respond to various types of cover glass by changing the position and inclination of the reflecting mirrors 63 and 64 according to the shape of the cover glass. For example, the defect of the side surface Gb can be inspected regardless of the inclination of the side surface Gb with respect to the horizontal direction by setting the inclination of the reflection surfaces 63a and 64a with respect to the horizontal direction according to the inclination of the side surface Gb with respect to the horizontal direction. Further, for example, by changing the position of the reflecting mirrors 63 and 64 in the y direction according to the width of the cover glass, the defect of the side surface Gb can be inspected regardless of the width of the cover glass.

In addition, according to the present embodiment, the height of the front end Gc and the rear end Gd is increased by moving the third camera 13 in the vertical direction in accordance with the height change of the cover glass G1 that passes under the third camera 13. Even when the distance changes, the third camera 13 can capture a sharp image in focus at the front end Gc and the rear end Gd. Therefore, it is possible to surely inspect the front end Gc and the rear end Gd for defects.

In the present embodiment, thick glass plates are used as the focal length adjustment

optical elements

61 and 62, but the form of the focal length adjustment

optical elements

61 and 62 is not limited thereto. For example, concave lenses may be used as the focal length adjustment

optical elements

61 and 62. Although the thickness of the glass plate and the shape of the concave lens are set according to the shape of the cover glass, the focal length easily extends when the concave lens is used. It is desirable to use glass plates as the

elements

61 and 62.

Further, in the present embodiment, the CPU 101 controls the moving unit 95 based on the image captured by the camera 92, so that the third time is adjusted according to the height change of the cover glass G1 that passes under the third camera 13. Although the camera 13 is moved in the vertical direction, the method of moving the third camera 13 in the vertical direction in accordance with the height change of the cover glass G1 passing under the third camera 13 is not limited to this. For example, information regarding the height change of the front end Gc and the rear end Gd may be stored in the ROM 103 in advance, and the CPU 101 may control the moving unit 95 based on this information. Further, for example, the height of the cover glass G1 may be measured with a laser displacement meter, and the CPU 101 may control the moving unit 95 based on the measurement result.

<Fourth embodiment>
In the first embodiment of the present invention, the three-dimensional illumination unit 30 includes a first region 31, a second region 32, and a third region 33, and the light emitting unit 30 a is substantially cylindrical in the second region 32 and the third region 33. Although arranged on the surface, the form of the three-dimensional illumination unit is not limited to this.

In the fourth embodiment of the present invention, all the strip-shaped light emitting units constituting the three-dimensional illumination unit have a light emitting block in which the light emitting units 30a are arranged in a straight line. Hereinafter, the optical inspection apparatus 4 according to the fourth embodiment will be described. In addition, since the difference between the optical inspection apparatus 4 according to the fourth embodiment and the optical inspection apparatus 1 is only the stereoscopic illumination unit, the stereoscopic illumination unit 30A included in the optical inspection apparatus 4 according to the fourth embodiment. A description of the same parts as those of the optical inspection apparatus 1 will be omitted.

FIG. 28 is a perspective view showing an outline of a three-dimensional illumination unit 30A included in the optical inspection device 4. The three-dimensional illumination unit 30A irradiates the cover glass G with light from a plurality of directions. The light emitted from the three-dimensional illumination unit 30A and reflected by the cover glass G enters the third camera 13 (see FIG. 1).

The three-dimensional illumination unit 30A includes a first region 31A having a substantially semi-cylindrical surface, and a second region 32A and a third region 33A having a substantially hemispherical surface or a substantially semi-elliptical spherical surface. The first region 31A, the second region 32A, and the third region 33A in the stereoscopic illumination unit 30A correspond to the first region 31, the second region 32, and the third region 33 in the stereoscopic illumination unit 30, respectively.

The first region 31A includes strip-shaped light emitting portions 31a-1, 31b-1, 31c-1, 32d-1, 31e-1, 31f-1, 31g-1, 31h-1, 31i-1, and 31j-1. . The band-shaped light emitting units 31a-1 to 31j-1 in the three-dimensional illumination unit 30A correspond to the band-shaped light emitting units 31a to 31j in the three-dimensional illumination unit 30.

The second region 32A has strip-like light emitting portions 32a-1, 32b-1, 32c-1, 32d-1, 32f-1, 32g-1, 32h-1, and the third region 33A has the strip-like light emitting portion 33a. -1, 33b-1, 33c-1, 33d-1, 33f-1, 33g-1, and 33h-1. The band-like light emitting units 32a-1 to 32d-1 and 32f-1 to 32h-1 in the three-dimensional illumination unit 30A correspond to the band-like light emitting units 32a to 32d and 32f to 32h in the three-dimensional illumination unit 30. The band-like light emitting units 33a-1 to 33d-1 and 33f-1 to 33h-1 in the three-dimensional illumination unit 30A correspond to the band-like light emitting units 33a to 33d and 33f to 33h in the three-dimensional illumination unit 30.

The three-dimensional illumination unit 30A includes a frame 34 that integrates the first region 31A, the second region 32A, and the third region 33A. The frame 34 is formed of a metal having excellent thermal conductivity such as aluminum. The frame 34 has two plates 34a, and a first region 31A is provided between the two plates 34a. The second region 32A and the third region 33A are provided outside the plate 34a.

FIG. 29 is a schematic diagram showing details of the strip-shaped light emitting section 31a-1. Since the belt-like light emitting portions 31a-1 to 31j-1 have the same configuration, only the belt-like light emitting portion 31a-1 will be described, and the description of the belt-like light emitting portions 31b-1 to 31j-1 will be omitted.

The band-shaped light emitting portion 31a-1 has a light emitting block 30b in which the light emitting portions 30a are arranged in a row so that the length in the longitudinal direction is L, a cylindrical lens 30c-1, and a lenticular lens 30e-1. Is a unit. The difference between the cylindrical lens 30c and the cylindrical lens 30c-1 is only the length in the longitudinal direction. Further, the difference between the lenticular lens 30e and the lenticular lens 30e-1 is only the length in the longitudinal direction.

The belt-like light emitting unit 31a-1 has two light emitting blocks 30b arranged in a straight line. The two light emitting blocks 30b are directly attached to the plate 34a via the attachment member 34b. The cylindrical lens 30c-1 is directly attached to the plate 34a via the attachment member 34c.

A lenticular lens 30e-1 is provided between the light emitting block 30b and the cylindrical lens 30c-1. The lenticular lens 30e-1 is attached to the light emitting block 30b via a support member 30f.

The light emitting block 30b and the cylindrical lens 30c-1 are provided on the plate 34a so that the tip surface p1 of the light emitting block 30b where the light emitting portion 30a is provided and the upper surface p2 of the cylindrical lens 30c-1 are substantially parallel. In other words, the extending direction of the light emitting block 30b and the extending direction of the cylindrical lens 30c-1 are substantially parallel.

FIG. 30 is a schematic diagram showing details of the belt-like light emitting part 32a-1. Since the belt-like light emitting portions 32a-1 to 32d-1, 32f-1 to 32h-1, 33a-1 to 33d-1, and 33f-1 to 33h-1 have the same configuration, only the belt-like light emitting portion 32a-1 is used. Explanation will be omitted, and the description of the band-like light emitting portions 32b-1 to 32d-1, 32f-1 to 32h-1, 33a-1 to 33d-1, and 33f-1 to 33h-1 will be omitted.

The belt-like light emitting part 32a-1 is a light emitting unit having a light emitting block 30b in which the light emitting parts 30a are arranged in a row so that the length in the longitudinal direction is L, a cylindrical lens 30c-2, and a plate 30g. . The only difference between the cylindrical lens 30c and the cylindrical lens 30c-2 is the length in the longitudinal direction.

The light emitting block 30b and the cylindrical lens 30c-2 are attached to the plate 30g. The plate 30g is formed of a metal having excellent thermal conductivity such as aluminum. The plate 30g is formed with a bent portion 30h for attaching the plate 30g to the plate 34a.

The light emitting block 30b and the cylindrical lens 30c-2 are provided on the plate 30g so that the upper surface p4 of the cylindrical lens 30c-2 is inclined with respect to the tip surface p3 provided with the light emitting portion 30a of the light emitting block 30b. In other words, the extending direction of the cylindrical lens 30c-1 is inclined with respect to the extending direction of the light emitting block 30b.

The band-like light emitting portions 31a-1 to 31j-1 have lenticular lenses 30e-1, but the band-like light emitting portions 32a-1 to 32d-1, 32f-1 to 32h-1, 33a-1 to 33d-1, and 33f-1 to 33h-1 do not have a lenticular lens. This is because the spot-like light of the light emitting part 30a does not appear side by side on the P surface formed at the left end and the right end of the cover glass G.

Returning to the explanation of FIG. The band-like light emitting portions 31a-1 to 31e-1 are located on the + x side from the central plane S1, and the band-like light emitting portions 31f-1 to 31j-1 are located on the −x side from the central plane S1. The strip-shaped light emitting portions 31a-1 to 31j-1 are not arranged on the center plane S1.

The band-like light emitting portions 31a-1 to 31j-1 are provided so that the optical axis intersects the intersection line between the center plane S1 and the mounting portion 40 (not shown in FIG. 28), that is, the central axis ax (see FIG. 31). (Detailed later).

The belt-like light emitting portions 32a-1 and 33a-1 are provided on the center plane S1. The band-like light emitting portions 32b-1 to 32d-1, 33b-1 to 33d-1 are located on the + x side from the center plane S1, and the band-like light emitting portions 32f-1 to 32h-1, 33f-1 to 33h-1 are Located on the −x side from the center plane S1.

The belt-like light emitting units 32a-1 and 33a-1 have a central axis facing the intersection (center point O1, see FIG. 31) between the central axis ax1 of the three-dimensional illumination unit 30A and the mounting unit 40. The strip-shaped light emitting portions 32b-1 to 32d-1, 32f-1 to 32h-1, 33b-1 to 33d-1, and 33f-1 to 33h-1 are substantially parallel to the strip-shaped light emitting portions 32a-1 and 33a-1. Provided.

FIG. 31 is a diagram illustrating the path of light emitted from the three-dimensional illumination unit 30A. In FIG. 31, while showing schematic structure when the solid-state illumination part 30A is cut | disconnected by center plane S1, the path | route of light is shown with a dashed-two dotted line.

The belt-like light emitting portion 31f-1 is provided so that the optical axis intersects the central axis ax. In the belt-like light emitting unit 31f-1, the cylindrical lens 30c-1 is provided between the light emitting block 30b and the central axis ax, and condenses the light emitted from the light emitting unit 30a in the vicinity of the central axis ax. In the first region 31A, the light emitting portions 30a are arranged substantially horizontally, and the tip surface p1 of the light emitting block 30b and the upper surface p2 of the cylindrical lens 30c-1 are substantially parallel, so that the light is emitted from the light emitting block 30b. The light passes through the cylindrical lens 30c-1 and is focused on the central axis ax.

The center axis of the strip-shaped light emitting portions 32a-1 and 33a-1 is directed to the center point O1. The cylindrical lens 30c-2 is provided between the light emitting block 30b and the center point O1 (center axis ax), and condenses the light emitted from the light emitting unit 30a in the vicinity of the center axis ax.

In the second region 32A and the third region 33A, the light emitting portions 30a are not arranged substantially horizontally, and the extending direction of the light emitting block 30b is inclined with respect to the horizontal direction. If the front end surface p3 of the light emitting block 30b and the upper surface p4 of the cylindrical lens 30c-2 are substantially parallel, the light emitted from the light emitting unit 30a is focused on a line substantially parallel to the front end surface p3, and is focused on the central axis ax. Do not tie. Therefore, in the second region 32A and the third region 33A, the upper surface p4 is inclined with respect to the tip surface p3 so that the light emitted from the light emitting unit 30a is focused on the central axis ax.

Thereby, in the second region 32A and the third region 33A, the light emitted from the light emitting unit 30a passes through the cylindrical lens 30c-2, and the light is applied to the P surface formed at the left end and the right end of the cover glass G. Irradiate and focus the light on the P plane. In addition, the second region 32A and the third region 33A irradiate light to the region A2 outside the range A1 in which the first region 31A can irradiate light. Thus, the second region 32A and the third region 33A have a function of supplementing the first region 31A.

According to the present embodiment, the cover glass G can be irradiated with light from various directions using the three-dimensional illumination unit 30A. In particular, in the second region 32A and the third region 33A, the upper surface p4 is inclined with respect to the tip surface p3, so that the focus of the light emitted from the light emitting unit 30a is on the P surface formed at the left and right ends of the cover glass G. Can be combined. In addition, the second region 32A and the third region 33A can supplement the first region 31A by inclining the upper surface p4 with respect to the tip surface p3. As a result, the number of light emitting blocks 30b included in the band-like light emitting units 31a-1 to 31j-1 can be reduced.

In addition, according to the present embodiment, since the frame 34 and the plate 30g formed of a material having high thermal conductivity are integrated to constitute the heat radiating member, the heat generated from the light emitting unit 30a and the like is efficiently obtained. It can dissipate heat.

Furthermore, as shown in FIG. 28, it is desirable to provide a blower unit 35 in the vicinity of the three-dimensional illumination unit 30A. The cooling effect by the heat radiating member (frame 34 and plate 30g) can be improved by sending wind from the blower 35 to the three-dimensional illumination unit 30A. Since the plate 30g extends in the y direction, the blower 35 is directed from the side surface (at least one of + y direction and -y direction) along the extending direction of the plate 30g (see the thick arrow in FIG. 28). ) Is preferably sent to the three-dimensional illumination unit 30A. In FIG. 28, the air blowing unit 35 is provided in the −y direction of the three-dimensional illumination unit 30A, but the position of the air blowing unit 35 is not limited to this. In FIG. 28, one blower 35 is provided, but the number of blowers 35 is not limited to this.

<Fifth embodiment>
In the first embodiment of the present invention, the coaxial illumination unit 20 includes an upper coaxial illumination 21 that is the coaxial illumination of the first camera 11 and a lower coaxial illumination 22 that is the coaxial illumination of the second camera 12. However, the form of the coaxial illumination unit is not limited to this.

In the fifth embodiment of the present invention, the coaxial illumination unit has a C-PL filter. Hereinafter, the optical inspection apparatus 5 according to the fifth embodiment will be described. In addition, since the difference between the optical inspection apparatus 5 according to the fifth embodiment and the optical inspection apparatus 1 is only the coaxial illumination section, the coaxial illumination section 20A included in the optical inspection apparatus 5 according to the fourth embodiment. A description of the same parts as those of the optical inspection apparatus 1 will be omitted.

FIG. 32 is a front view showing an outline of the optical inspection apparatus 5 according to the fifth embodiment. The coaxial illumination unit 20A includes an upper coaxial illumination 21 that is the coaxial illumination of the first camera 11, a lower coaxial illumination 22 that is the coaxial illumination of the second camera 12, and C-PL filters 23a and 23b. The C-PL filter 23 a is provided below the first camera 11, and the C-PL filter 23 b is provided above the second camera 12.

Each of the C-PL filters 23a and 23b is a circularly polarizing filter having a polarizing plate and a 1 / 4λ phase difference plate that gives a 1 / 4λ phase difference to transmitted light that has passed through the polarizing plate. The quarter-wave retardation plate converts linearly polarized light into circularly polarized light. The C-PL filters 23a and 23b are provided such that the polarizing plates are positioned on the half mirrors 21h and 22h, and the 1 / 4λ phase difference plate is positioned on the side far from the half mirrors 21h and 22h. Since the C-PL filters 23a and 23b are already known, detailed description thereof is omitted.

The C-PL filters 23a and 23b are provided adjacent to the first camera 11 and the second camera 12, respectively. The C-PL filters 23a and 23b are provided such that the plane in the direction substantially orthogonal to the thickness direction is slightly inclined with respect to the direction substantially orthogonal to the optical axis oax.

Some of the light emitted from the light source 21a and reflected downward by the half mirror 21h may be transmitted through the cover glass G and reflected from the surface of the imaging lens 12a. When this reflected light is incident on the first camera 11, there is a possibility that a bright light line is included in the center of the image captured by the first camera 11. The C-PL filter 23 b prevents light that has passed through the cover glass G and reflected from the surface of the imaging lens 12 a from entering the first camera 11. Accordingly, it is possible to prevent a bright light line from being included in the center of the image captured by the first camera 11.

Similarly, the C-PL filter 23a is irradiated from the light source 22a, reflected upward by the half mirror 22h, transmitted through the cover glass G, and reflected from the surface of the imaging lens 11a so that it does not enter the second camera 12. To do. Accordingly, it is possible to prevent a bright light line from being included in the center of the image captured by the second camera 12.

In this embodiment, the C-PL filters 23a and 23b are provided, but the C-PL filter 23a is not essential.

The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and design changes and the like within a scope not departing from the gist of the present invention are included. . A person skilled in the art can appropriately change, add, or convert each element of the embodiment. For example, the side surface inspection unit 60 and the height acquisition unit 90 may be applied to the

optical inspection devices

4 and 5 according to the fourth and fifth embodiments. Further, for example, the optical inspection apparatus 2 according to the second embodiment and the optical inspection apparatus 5 according to the fifth embodiment may be combined, or the optical inspection apparatus 4 according to the fourth embodiment may be combined with the optical inspection apparatus 4 according to the fourth embodiment. The optical inspection device 5 according to the fifth embodiment may be combined.

In the above embodiment, the inspection objects (inspection objects) of the optical inspection apparatuses 1 to 5 are the cover glasses G and G1, but the inspection object of the optical inspection apparatuses 1 to 5 is not limited to the cover glass. For example, the inspection target of the optical inspection apparatuses 1 to 5 may be glass used for a touch pad of a laptop personal computer.

Further, in the present invention, “substantially” is a concept that includes not only a case where they are exactly the same but also errors and deformations that do not lose the identity. For example, “substantially horizontal” is not limited to being strictly horizontal, but is a concept including an error of about several degrees, for example. Further, for example, when simply expressing as parallel, orthogonal, etc., not only strictly parallel, orthogonal, etc. but also cases of substantially parallel, substantially orthogonal, etc. are included. Further, in the present invention, “near” means including a region in a certain range (which can be arbitrarily determined) near a reference position.

1, 2: Optical inspection device 10, 10 A: Imaging unit 11: First camera 12: Second camera 13: Third camera 11 a, 12 a, 13 a: Imaging lens 11 b, 12 b, 13 b: Line sensor 13 c: Third camera Field position 20, 20A: Coaxial illumination unit 21, 21A: Upper coaxial illumination 22, 22A: Lower coaxial illumination 21a, 22a: Light source 21b, 22b: Integrator 21c, 22c: Condensing lens 21d, 22d: Apertures 21e, 22e: Collimator lenses 21f, 22f: mirrors 21g, 22g: Fresnel lenses 21h, 22h: half mirrors 23a, 23b: C-PL filter 30, 30A: three-dimensional illumination unit 30a: light emitting unit 30b: light emitting blocks 30c, 30c-1, 30c- 2: Cylindrical lens 30d: Light emitting block 30e, 30e-1: Wrench Dura lens 30g: plate 30h: bent portion 31, 31A: first region 31a to 31j, 31a-1 to 31j-1: strip-like light emitting unit 32, 32A: second region 32a to 32i, 32a-1 to 32d-1, 32f -1 to 32h-1: Band-shaped light emitting portions 33, 33A: Third regions 33a to 33i, 33a-1 to 33d-1, 33f-1 to 33h-1: Band-shaped light emitting portions 34: Frame 34a: Plates 34b, 34c: Mounting member 35: blower 40: placement unit 40a: roller 50: transport unit 60: side surface inspection unit 61, 62: focal length adjusting optical element 63, 64: reflecting mirror 63a, 64a: reflecting surface 71: integrated circuit 72 : Input unit 73: Output unit 74: Power supply unit 75: Communication I / F
81: Position detection sensor 82: Position detection sensor 90: Height acquisition unit 91: Surface light source 92: Camera 93: Reflector 95: Moving unit 100: Personal computer 101: CPU
102: RAM
103: ROM
104: Input / output interface 105: Communication I / F
106: Media I / F
111: Input device 112: Output device 113: Storage medium

Claims

A placement unit for placing an object to be inspected in a horizontal direction;
A transport unit configured to move the inspection object placed on the placement unit along a transport direction;
One-dimensional imaging means for imaging the object to be inspected from substantially vertically upward, one-dimensional imaging means arranged so that the longitudinal direction is substantially orthogonal to the transport direction;
A light irradiating unit having a plurality of light emitting units for irradiating the inspection object with light;
With
The light irradiation unit includes a first region of a substantially semi-cylindrical surface having a central axis positioned on a central surface that is a surface in a substantially vertical direction including the one-dimensional imaging unit, and a substantially region formed at both ends of the first region. A second region and a third region of a hemispherical surface or a substantially semi-elliptical spherical surface,
The first region has a plurality of strip-like light emitting parts in which the light emitting parts are arranged along a direction substantially orthogonal to the transport direction,
The belt-like light emitting portion is provided in a region other than the vicinity of the center plane in the first region,
In the second region and the third region, the light emitting units are arranged on the center plane.
The belt-like light emitting portion is provided such that the optical axis intersects with the intersection line between the center plane and the upper surface of the mounting portion,
2. The optical inspection apparatus according to claim 1, wherein the band-shaped light-emitting unit includes a first band-shaped light-emitting unit in which an angle between an optical axis and the center plane is approximately 8 degrees or approximately 17 degrees.
The transport unit is controlled so as to transport the inspection object at a constant speed, the one-dimensional imaging unit is driven so as to capture images at a constant interval, and is synchronized with imaging by the one-dimensional imaging unit. A first light-emitting region that is a half region delimited by the central plane of the first region, a second light-emitting region other than the first light-emitting region in the first region, and the second region And a third light emitting region on the central plane, a fourth light emitting region on the central plane of the third region, and a control unit for separately irradiating the first strip light emitting portion. Item 3. The optical inspection device according to Item 2.
The said light irradiation part has a cylindrical lens arrange | positioned between the said strip | belt-shaped light emission part, and the intersection line of the said center plane and the upper surface of the said mounting part. The any one of Claim 1 to 3 characterized by the above-mentioned. An optical inspection apparatus according to claim 1.
First imaging means provided on the upper side or the lower side of the placement unit,
A second image pickup means provided on the opposite side of the first image pickup means and the mounting portion so that the optical axis coincides with the optical axis of the first image pickup means;
A first coaxial illumination that irradiates the inspection object with parallel light from a normal direction, the first coaxial illumination being a coaxial illumination of the first imaging means;
A second coaxial illumination provided on the opposite side of the first coaxial illumination and the mounting portion, the second coaxial illumination being a coaxial illumination of the second imaging means;
With
The first imaging means is irradiated with light irradiated from the first coaxial illumination and specularly reflected by the inspection object,
The second imaging means receives light irradiated from the second coaxial illumination and regularly reflected by the inspection object, and light irradiated from the first coaxial illumination and transmitted through the inspection object. The optical inspection apparatus according to any one of claims 1 to 4, wherein the optical inspection apparatus is characterized.
A first mode in which the transport unit is controlled so as to transport the object to be inspected at a constant speed, and the first coaxial illumination is irradiated with a first intensity, and the second coaxial illumination is irradiated with the first intensity. The first coaxial illumination or the second coaxial illumination is irradiated with the three irradiation patterns of the second form irradiated with the above, the third form irradiated with the first coaxial illumination with the second intensity, and the first An image is acquired by the first imaging unit in accordance with the irradiation of the first form, an image is acquired by the second imaging unit in accordance with the irradiation of the second form, and the second is acquired in accordance with the irradiation of the third form. The optical inspection apparatus according to claim 5, further comprising a second control unit that drives the first imaging unit and the second imaging unit so that an image is acquired by the imaging unit.
A second image pickup means provided on the opposite side of the one-dimensional image pickup means and the mounting portion so that the optical axis coincides with the optical axis of the one-dimensional image pickup means;
A first coaxial illumination that irradiates the inspection object with parallel light from a normal direction, the first coaxial illumination being a coaxial illumination of the one-dimensional imaging means;
A second coaxial illumination provided on the opposite side of the first coaxial illumination and the mounting portion, the second coaxial illumination being a coaxial illumination of the second imaging means;
With
The light irradiation unit is provided between the one-dimensional imaging unit and the transport unit,
The one-dimensional imaging means is irradiated with light that is irradiated from the light irradiation unit or the first coaxial illumination and is regularly reflected by the inspection object,
The second imaging means receives light irradiated from the second coaxial illumination and regularly reflected by the inspection object, and light irradiated from the first coaxial illumination and transmitted through the inspection object. The optical inspection apparatus according to any one of claims 1 to 4, wherein the optical inspection apparatus is characterized.
A first mode in which the transport unit is controlled so as to transport the object to be inspected at a constant speed, and the first coaxial illumination is irradiated with a first intensity, and the second coaxial illumination is irradiated with the first intensity. The first coaxial illumination or the second coaxial illumination is irradiated with the three irradiation patterns of the second form irradiated with the above, the third form irradiated with the first coaxial illumination with the second intensity, and the first An image is acquired by the one-dimensional imaging unit in accordance with the irradiation of the first form, an image is acquired by the second imaging unit in accordance with the irradiation of the second form, and the second in accordance with the irradiation of the third form. The optical inspection apparatus according to claim 7, further comprising a third control unit that drives the one-dimensional imaging unit and the second imaging unit so that an image is acquired by the imaging unit.
The said light irradiation part is provided adjacent to the said light emission part, and has a light-diffusion plate which diffuses the light irradiated from the said light emission part. The Claim 1 characterized by the above-mentioned. Optical inspection device.
A focal length adjusting optical element for adjusting a focal length of the one-dimensional imaging means;
A reflector provided adjacent to the mounting portion;
With
The focal length adjusting optical element and the reflecting mirror are provided on the center plane,
In a plan view, a placement area that is an area on the placement section on which the inspection object is placed is positioned below the vertical direction of the one-dimensional imaging means,
In plan view, the reflecting mirror is provided at a position outside the mounting area and adjacent to the mounting area in a direction substantially orthogonal to the transport direction,
The reflecting surface of the reflecting mirror is substantially flat,
The reflecting surface extends substantially along the transport direction so that a line intersecting the center plane is inclined with respect to a horizontal plane,
The optical inspection apparatus according to claim 1, wherein the focal length adjustment optical element is disposed so as to overlap a line connecting the one-dimensional imaging unit and the reflecting mirror. .
The optical inspection apparatus according to claim 10, wherein the focal length adjusting optical element is a glass plate, and is provided such that both end faces substantially orthogonal to the plate thickness direction are horizontal.
A moving unit for moving the one-dimensional imaging means in the vertical direction;
A height acquisition unit for acquiring the height of the inspection object;
Based on the information acquired by the height acquisition unit, the moving unit is controlled so that the one-dimensional imaging unit is moved in the vertical direction in accordance with the height change of the inspection object passing under the one-dimensional imaging unit. A movement control unit to be moved;
The optical inspection apparatus according to claim 1, further comprising:
The height acquisition unit includes a surface light source that emits light in a direction substantially orthogonal to the transport direction, and a side surface imaging unit that receives light that has been irradiated from the surface light source and passed through the inspection object. The optical inspection apparatus according to claim 12.
The light irradiation unit includes a light emitting block in which the light emitting units are arranged in a row in the second region and the third region, and a second cylindrical lens through which light emitted from the light emitting unit passes. ,
In the second region and the third region, the extending direction of the light emitting block is inclined with respect to the horizontal direction,
The extending direction of the second cylindrical lens is inclined with respect to the extending direction of the light emitting block in the second region and the third region. The optical inspection device according to item.
The light irradiation unit has a heat dissipation member formed of a material having high thermal conductivity,
The optical inspection apparatus according to claim 1, wherein the light emitting unit is provided on the heat dissipation member.
A blower for sending air to the heat dissipating member;
The heat dissipation member has a plurality of plates provided with the light emitting part,
The plate extends in a direction substantially perpendicular to the transport direction,
The optical inspection apparatus according to claim 15, wherein the air blowing unit sends wind in a direction along the extending direction of the plate.
The second imaging means is provided below the placement unit,
A circular polarizing filter is provided above the second imaging means,
The circularly polarizing filter is provided such that a plane in a direction substantially orthogonal to the thickness direction is slightly inclined with respect to a direction substantially orthogonal to the optical axis of the second imaging means. The optical inspection apparatus according to any one of 5 to 8.