JP2021179344A - Exterior appearance inspection device, and illumination method - Google Patents

Abstract

To make a range to be irradiated with light adequately spread with respect to an inspection object, and to secure necessary and sufficient illuminance.SOLUTION: In an inner wall surface 32 (a light reflection surface) of a light reflection member 3, a plurality of mirror surfaces 33 are arrayed that regularly reflect light Li respectively, and the mirror surface 33 has a concave shape that converges the light Li projected by a projector 5 to a convergence position P between the mirror surface 33 and a workpiece W. Therefore, light Lr regularly reflected upon the mirror surface 33 spreads after converged in the convergence position P between the mirror surface 33 and the workpiece W, and the workpiece W is irradiated with the light.SELECTED DRAWING: Figure 1

Description

The present invention relates to a lighting technique for irradiating an inspection object with light when inspecting the appearance of the inspection object.

Conventionally, a technique for inspecting the appearance of an inspection object by irradiating the inspection object with light and taking an image of the inspection object has been known. For example, in the inspection devices of Patent Documents 1 and 2, a light reflecting surface having a curved shape such as a dome shape or a tunnel shape is arranged facing the inspection object, and the light incident on the reflecting surface from the light source is reflected by the reflecting surface. Then, the object to be inspected is irradiated.

JP 2011-179882 Patent No. 6482710

In such a configuration in which the light reflected by the light reflecting surface having a concave curved shape (dome shape or tunnel type) with respect to the inspection object is irradiated to the inspection object, the state and curved shape of the surface of the light reflecting surface are inspected. Depending on the positional relationship of the object, the range of light irradiation may be wide and sufficient illuminance may not be secured, or the range of light irradiation may be narrow and the entire inspection object may not be illuminated. ..

The present invention has been made in view of the above problems, and an object of the present invention is to appropriately extend the range of irradiation with light to an inspection object and to secure necessary and sufficient illuminance.

The visual inspection apparatus according to the first aspect of the present invention is a light reflecting member having a support portion for supporting the inspection object and a light reflecting surface having a curved shape facing the inspection object and having a concave shape with respect to the inspection object. And a projector that projects light on the light-reflecting surface, the light projected by the projector on the light-reflecting surface is reflected by the light-reflecting surface and then irradiated to the inspection object, and the light is emitted on the light-reflecting surface. A plurality of mirror surfaces that reflect positively are arranged, and the mirror surface has a concave shape, a convex shape, or a planar shape that collects the light projected by the projector between the mirror surface and the inspection object.

The lighting method according to the first aspect of the present invention includes a step of projecting light from a projector onto a light reflecting surface having a curved shape facing the inspection object and having a concave shape with respect to the inspection object, and light projected by the projector. The light-reflecting surface is provided with a step of irradiating the object to be inspected by reflecting the light on the light-reflecting surface. It has a concave, convex or planar shape that collects light between the mirror surface and the object to be inspected.

In the present invention (visual inspection apparatus and lighting method) configured in this way, a light reflecting surface having a curved shape recessed with respect to the inspection object faces the inspection object and is projected from the projector onto the light reflecting surface. The light is reflected by the light reflecting surface and irradiates the object to be inspected. In particular, on the light reflecting surface, a plurality of mirror surfaces that regularly reflect light are arranged, and the mirror surface is a concave shape, a convex shape, or a flat surface that collects the light projected by the projector between the mirror surface and the inspection object. Has a shape. Therefore, it is possible to appropriately extend the range of irradiation with light to the object to be inspected and to secure the necessary and sufficient illuminance.

Further, it seems that a plurality of mirror surfaces are arranged so that the geometric centroids of each of the six mirror surfaces adjacent to one mirror surface are arranged at intervals of 60 degrees on the circumference centered on the geometric center of the one mirror surface. In addition, a visual inspection device may be configured. In such a configuration, a plurality of mirror surfaces can be closely arranged.

By the way, various shapes of the mirror surface are assumed. For example, the mirror surface may have a regular hexagon or a circle.

Further, the camera is further provided with an image pickup unit that captures an inspection object irradiated with the light reflected by the light reflecting surface by the camera while positioning the cameras at a plurality of image pickup positions different from each other in the rotation direction about a predetermined axis. The projector may configure the visual inspection device so that the mirror surface that projects light among the plurality of mirror surfaces is changed according to the imaging position where the camera that images the inspection object is located. In such a configuration, since the inspection object can be imaged from a plurality of directions corresponding to a plurality of imaging positions, it is advantageous to accurately detect scratches and the like of the inspection object. The projector changes the mirror surface that projects light among the plurality of mirror surfaces according to the imaging position of the camera that images the inspection object. That is, light is projected on the mirror surface selected according to the image pickup position of the camera from among the plurality of mirror surfaces. At this time, since the mirror surface has the above-mentioned shape, the light reflected by the mirror surface selected from the plurality of mirror surfaces appropriately expands the irradiation range of the inspection object and secures the necessary and sufficient illuminance. It becomes possible.

Incidentally, various specific examples of the curved shape are assumed. For example, the curved shape may be a dome shape or a tunnel shape.

Further, the light reflecting member has a spherical outer wall surface, the exit pupil of the projector is deviated from the center of the spherical shape of the outer wall surface, and the support portion is the center of the spherical shape of the outer wall surface. The visual inspection device may be configured to support the inspection object on the opposite side of the exit pupil. In such a configuration, the light projected from the projector onto the light reflecting surface of the light reflecting member can accurately irradiate the inspection object supported by the support portion.

The visual inspection apparatus according to the second aspect of the present invention is a light reflecting member having a support portion for supporting the inspection object and a light reflecting surface having a curved shape facing the inspection object and having a concave shape with respect to the inspection object. The light reflecting surface diffuses and reflects the light projected from the projector to irradiate the inspection object, and the light reflecting surface diffuses on the light reflecting surface. The amount of reflected light has a directivity with a peak in a predetermined direction.

The lighting method according to the second aspect of the present invention includes a step of projecting light from a projector onto a light reflecting surface having a curved shape facing the inspection object and having a concave shape with respect to the inspection object, and light projected by the projector. The light-reflecting surface comprises a step of diffusing and reflecting the light by a light-reflecting surface to irradiate the object to be inspected, and the light-reflecting surface has a directivity in which the amount of light diffusely reflected by the light-reflecting surface has a peak in a predetermined direction.

In the present invention (visual inspection apparatus and lighting method) configured in this way, a light reflecting surface having a curved shape recessed with respect to the inspection object faces the inspection object and is projected from the projector onto the light reflecting surface. The light is reflected by the light reflecting surface and irradiates the object to be inspected. In particular, the light reflecting surface diffusely reflects light while having directivity. Therefore, it is possible to appropriately extend the range of irradiation with light to the object to be inspected and to secure the necessary and sufficient illuminance.

As described above, according to the present invention, it is possible to appropriately widen the range of light irradiation with respect to the inspection object and to secure the necessary and sufficient illuminance.

FIG. 3 is a partial cross-sectional view schematically showing a configuration of a visual inspection apparatus according to a first embodiment of the present invention. The perspective view which shows typically the appearance of the light reflection member included in the appearance inspection apparatus of FIG. FIG. 3 is a block diagram showing an electrical configuration included in the visual inspection device of FIG. 1. The figure which shows typically the switching mode of the light projection range by a projector. A partial cross-sectional view schematically showing the configuration of a visual inspection apparatus according to a comparative example. FIG. 3 is a partial cross-sectional view schematically showing a configuration of a visual inspection apparatus according to a second embodiment of the present invention. FIG. 3 is a partial cross-sectional view schematically showing a configuration of a visual inspection apparatus according to a third embodiment of the present invention. The figure which shows the 1st example of the arrangement aspect of a mirror surface. The figure which shows the 2nd example of the arrangement aspect of a mirror surface. FIG. 3 is a partial cross-sectional view schematically showing a configuration of a visual inspection apparatus according to a fourth embodiment of the present invention. FIG. 9 is a diagram schematically showing the light reflection characteristics of the inner wall surface of the visual inspection apparatus of FIG. The perspective view which shows typically the deformation example of the shape of the light-reflecting member.

FIG. 1 is a partial cross-sectional view schematically showing the configuration of the visual inspection apparatus according to the first embodiment of the present invention, and FIG. 2 is a perspective view schematically showing the appearance of the light reflecting member included in the visual inspection apparatus of FIG. FIG. 3 is a block diagram showing an electrical configuration included in the visual inspection apparatus of FIG. 1. In the figures of the present specification, the X direction which is the horizontal direction, the Y direction which is the horizontal direction orthogonal to the X direction, and the Z direction which is the vertical direction are appropriately shown.

The visual inspection device 1 includes a work support portion 2 that supports the work W to be inspected. In the example of FIG. 1, the work support portion 2 has a horizontal table 21 and supports the work W placed on the table 21. However, the specific configuration of the work support portion 2 is not limited to this, and the work support portion 2 may be a robot arm that supports the work W.

The visual inspection device 1 includes a dome-shaped light reflecting member 3 that faces the work W supported by the work support portion 2 from above. As shown in FIG. 2, the outer wall surface 31 of the light reflecting member 3 is a spherical surface So.

On the other hand, the inner wall surface 32 of the light reflecting member 3 faces the work W supported by the work support portion 2 from above and has a curved shape recessed with respect to the work W. The inner wall surface 32 is a specular reflection surface that specularly reflects light. Specifically, the inner wall surface 32 has a plurality of mirror surfaces 33 arranged so as to form a curved shape, and each mirror surface 33 has a concave shape and functions as a concave mirror. The concave shape of the mirror surface 33 may be a spherical surface or a shape different from the spherical surface. As described above, the inner wall surface 32 is composed of a plurality of mirror surfaces 33 (concave mirrors) facing the work W from different directions.

The shape of the inner wall surface 32 is roughly a spherical surface Si (a surface in contact with the boundary of adjacent mirror surfaces 33) shown by a broken line in FIG. 1, but in detail, each mirror surface 33 is recessed from the spherical surface Si. Such a light reflecting member 3 can be formed, for example, by finishing the inner wall surface of a metal dome into a spherical surface and then denting a portion of the inner wall surface corresponding to each mirror surface 33.

Further, the visual inspection device 1 includes a projector 5 facing the inner wall surface 32 of the light reflecting member 3 from below. The exit pupil 51 of the projector 5 is deviated from the center Co of the spherical surface So (common with the center of the spherical Si), and an interval Δ is provided between the exit pupil 51 and the center Co in the X direction. On the other hand, the above-mentioned table 21 is deviated from the center Co on the opposite side of the projector 5, and an interval Δ is provided in the X direction between the center of the table 21 and the center Co of the spherical surface So. Therefore, in a plan view from the vertical direction Z, the exit pupil 51 of the projector 5 and the work W supported by the table 21 are arranged so as to sandwich the center Co.

The projector 5 is a DMD (Digital Mirror Device) or a liquid crystal device (Liquid).
It has a spatial light modulation element such as Crystal on Silicon), a light source, and a projection lens, and projects light emitted from the light source and modulated by the spatial light modulation element by the projection lens. The projection lens is a so-called fisheye lens, and the projector 5 can project light onto the entire area of the inner wall surface 32. The projector 5 projects light Li onto the inner wall surface 32 of the light reflecting member 3. On the other hand, a plurality of mirror surfaces 33 are arranged on the inner wall surface 32, and each mirror surface 33 has a concave shape. The mirror surface 33 positively reflects the light Li incident from the projector 5 and condenses it on the condensing position P. The light collecting position P is provided between the mirror surface 33 and the work W. Therefore, the light Lr that is specularly reflected by the mirror surface 33 is focused on the focusing position P, then spreads, and is irradiated on the work W.

Further, the visual inspection device 1 includes a camera 61 that captures an image of the work W supported by the work support portion 2, and a camera drive mechanism 62 that drives the camera 61. The camera 61 is rotatably supported around the center line Cy of the spherical surface So parallel to the Y direction (common with the center line of the spherical surface Si), and a plurality of images taken differently from each other in the rotation direction centered on the center line Cy. It can move between positions Ia, Ib, and Ic. Then, the camera drive mechanism 62 drives the camera 61 to position the camera 61 at one of the plurality of imaging positions Ia, Ib, and Ic. In the example of FIG. 1, the camera 61 is located at the imaging position Ia. The specific configuration for locating the camera 61 at the imaging positions Ia, Ib, and Ic is not limited to this example. For example, the camera 61 may be arranged at each of the imaging positions Ia, Ib, and Ic without providing the camera drive mechanism 62.

Further, the light reflecting member 3 has openings Oa, Ob, and Occ corresponding to these imaging positions Ia, Ib, and Ic. Therefore, the camera 61 located at the imaging position Ia images the work W through the opening Oa, the camera 61 located at the imaging position Ib images the work W through the opening Ob, and the camera 61 located at the imaging position Ic. Image the work W through the opening Occ.

Further, the visual inspection device 1 includes a control unit 7 (FIG. 3) composed of an FPGA (Field-Programmable Gate Array) or a processor. The control unit 7 has a function of controlling the projector 5, the camera 61, and the camera drive mechanism 62, and the camera 61 irradiates the work W with light Lr from the projector 5 via the inner wall surface 32 of the light reflecting member 3. The appearance of the work W is inspected based on the image obtained by capturing the work W. Specifically, the presence or absence of scratches on the appearance of the work W is inspected.

Incidentally, the projector 5 can project the light Li onto the mirror surface 33 existing in the area selected from the inner wall surface 32. Specifically, the projector 5 switches the mirror surface 33 that projects the light Li according to the position of the camera 61. FIG. 4 is a diagram schematically showing a mode of switching the projection range of light by the projector. As shown in FIG. 4, the projector 5 projects optical Li into an area of the openings Oa, Ob, and Occ that is adjacent to the opening facing the camera 61. At this time, the light Li is projected in a ring shape in a plan view from the Z direction. Therefore, when the camera 61 is located at the imaging position Ia, the light Li is projected onto the mirror surface 33 around the opening Oa. When the camera 61 is located at the imaging position Ib, the light Li is projected onto the mirror surface 33 adjacent to the opening Ob and the mirror surface 33 located at the same height as the mirror surface 33. The same applies when the camera 61 is located at the imaging position Ic.

In the first embodiment configured in this way, a wide range of light irradiation to the work W can be secured. This point will be described with reference to FIG. Here, FIG. 5 is a partial cross-sectional view schematically showing the configuration of the visual inspection apparatus according to the comparative example. The only difference between the first embodiment of FIG. 1 and the comparative example of FIG. 5 is the configuration of the inner wall surface 32 of the light reflecting member 3. That is, in the comparative example, the inner wall surface 32 is a spherical Si, which is a spherical mirror that specularly reflects light Li. When light Li is projected from the projector 5 onto such an inner wall surface 32, the light Lr reflected by the inner wall surface 32 is focused toward the work W. As a result, the range in which the light Lr is irradiated to the work W is narrowed.

On the other hand, in the first embodiment, a plurality of mirror surfaces 33 that regularly reflect light Li are arranged on the inner wall surface 32 (light reflecting surface) of the light reflecting member 3, and the mirror surface 33 is formed by the projector 5. It has a concave shape that condenses the projected light Li at the condensing position P between the mirror surface 33 and the work W. Therefore, the light Lr that is specularly reflected by the mirror surface 33 is focused on the condensing position P between the mirror surface 33 and the work W, and then spreads and irradiates the work W. As a result, it is possible to appropriately expand the range in which the light Lr is irradiated with respect to the work W and to secure the necessary and sufficient illuminance.

Further, while the camera 61 is positioned at a plurality of imaging positions Ia, Ib, and Ic that are different from each other in the rotation direction about the center line Cy (predetermined axis), the work is irradiated with the light Lr that is specularly reflected by the inner wall surface 32. W is imaged by the camera 61. In such a configuration, since the work W can be imaged from a plurality of directions corresponding to a plurality of imaging positions Ia, Ib, and Ic, it is advantageous to accurately detect scratches on the work W. Further, the projector 5 changes the mirror surface 33 that projects the light Li among the plurality of mirror surfaces 33 according to the imaging positions Ia, Ib, and Ic of the camera 61 that images the work W. That is, the light Li is projected onto the mirror surface 33 selected according to the imaging positions Ia, Ib, and Ic of the camera 61 from the plurality of mirror surfaces 33 arranged on the inner wall surface 32. At this time, since the mirror surface 33 has a concave shape that collects light at the light collecting position P, the range in which the light Lr reflected by the mirror surface 33 selected from the plurality of mirror surfaces 33 is irradiated in the work W is appropriate. It is possible to secure the necessary and sufficient illuminance while expanding to.

Further, the light reflecting member 3 has a spherical outer wall surface 31, and the exit pupil 51 of the projector 5 is deviated from the spherical center Co of the outer wall surface 31. On the other hand, the table 21 supports the work W on the opposite side of the exit pupil 51 of the projector 5 with respect to the spherical center Co of the outer wall surface 31. In such a configuration, the light projected from the projector 5 onto the inner wall surface 32 of the light reflecting member 3 is emitted toward the work W by the curved shape of the inner wall surface 32. As a result, the work W can be accurately irradiated with light.

FIG. 6 is a partial cross-sectional view schematically showing the configuration of the visual inspection apparatus according to the second embodiment of the present invention. The difference between the second embodiment and the above embodiment is the shape of the mirror surface 33. Therefore, here, the description will be centered on the differences from the above-described embodiment, and the common points will be referred to with corresponding reference numerals and the description thereof will be omitted.

As shown in FIG. 6, also in the second embodiment, the inner wall surface 32 has a plurality of mirror surfaces 33 arranged so as to form a curved shape. However, each mirror surface 33 has a convex shape and functions as a convex mirror. The convex shape of the mirror surface 33 may be a spherical surface or a shape different from the spherical surface. As described above, the inner wall surface 32 is composed of a plurality of mirror surfaces 33 (convex mirrors) facing the work W from different directions. Then, the light Li projected from the projector 5 onto the mirror surface 33 is specularly reflected by the mirror surface 33.

As described above, in the second embodiment, the mirror surface 33 has a convex shape, and the light Lr reflected by the mirror surface 33 travels toward the work W while spreading due to the convex shape of the mirror surface 33, and then the work. W is irradiated. This makes it possible to secure a wide range in which the light Lr is irradiated to the work W.

Further, also in the second embodiment, the light Li is projected onto the mirror surface 33 selected according to the imaging positions Ia, Ib, and Ic of the camera 61 from among the plurality of mirror surfaces 33 arranged on the inner wall surface 32. At this time, since the mirror surface 33 has a convex shape, the light Lr reflected by the mirror surface 33 selected from the plurality of mirror surfaces 33 appropriately expands the range irradiated by the work W and provides necessary and sufficient illuminance. It is possible to secure it.

FIG. 7 is a partial cross-sectional view schematically showing the configuration of the visual inspection apparatus according to the third embodiment of the present invention. The difference between the third embodiment and the above embodiment is the shape of the mirror surface 33. Therefore, here, the description will be centered on the differences from the above-described embodiment, and the common points will be referred to with corresponding reference numerals and the description thereof will be omitted.

As shown in FIG. 7, also in the third embodiment, the inner wall surface 32 has a plurality of mirror surfaces 33 arranged so as to form a curved shape. However, each mirror surface 33 has a planar shape and functions as a planar mirror. As described above, the inner wall surface 32 is composed of a plurality of mirror surfaces 33 (plane mirrors) facing the work W from different directions. Then, the light Li projected from the projector 5 onto the mirror surface 33 is specularly reflected by the mirror surface 33.

As described above, in the third embodiment, the mirror surface 33 has a planar shape, and the light Lr reflected by the mirror surface 33 travels toward the work W without being narrowed, and then is irradiated to the work W. As a result, it is possible to appropriately expand the range in which the light Lr is irradiated with respect to the work W and to secure the necessary and sufficient illuminance.

Further, also in the third embodiment, the light Li is projected onto the mirror surface 33 selected according to the imaging positions Ia, Ib, and Ic of the camera 61 from among the plurality of mirror surfaces 33 arranged on the inner wall surface 32. At this time, since the mirror surface 33 has a planar shape, the light Lr reflected by the mirror surface 33 selected from the plurality of mirror surfaces 33 appropriately expands the range irradiated by the work W and provides necessary and sufficient illuminance. It is possible to secure it.

By the way, in the first to third embodiments, a plurality of mirror surfaces 33 are two-dimensionally arranged on the inner wall surface 32. Subsequently, the arrangement mode of the mirror surface 33 will be described. FIG. 8A is a diagram showing a first example of a mirror surface arrangement mode, and FIG. 8B is a diagram showing a second example of a mirror surface arrangement mode. In both figures, the two-dimensional arrangement of the mirror surface 33 and the arrangement of the mirror surface 33 in the cross section shown in FIG. 1, FIG. 6 or FIG. 7 are shown in association with each other.

In the first example, the mirror surface 33 has a circular shape, and in the second example, the mirror surface 33 has a regular hexagon. Then, in any of the two-dimensional arrangements of the first example and the second example, six mirror surfaces 33 are arranged at equal angular intervals around one mirror surface 33. In other words, the geometric center of gravity Ga of each of the six mirror surfaces 33 adjacent to one mirror surface 33 (for example, the mirror surface 33 in the center of the figure) is along the circumference A centered on the geometric center of gravity Go of the one mirror surface 33. They are lined up at intervals of 60 degrees. In such a configuration, a plurality of mirror surfaces 33 can be densely arranged on the inner wall surface 32.

FIG. 9 is a partial cross-sectional view schematically showing the configuration of the visual inspection apparatus according to the fourth embodiment of the present invention, and FIG. 10 is a diagram schematically showing the light reflection characteristics of the inner wall surface of the visual inspection apparatus of FIG. Is. In FIG. 10, the shape of the inner wall surface 32 is approximated by a straight line. The difference between the fourth embodiment and the above embodiment is the configuration of the inner wall surface 32. Therefore, here, the description will be centered on the differences from the above-described embodiment, and the common points will be referred to with corresponding reference numerals and the description thereof will be omitted.

As shown in FIG. 9, also in the second embodiment, the inner wall surface 32 of the light reflecting member 3 has a curved shape recessed with respect to the work W. However. The inner wall surface 32 is a smooth curved surface, and in this example, it is a spherical surface Si. Further, the inner wall surface 32 is a diffuse reflection surface that diffusely reflects light Li. Such a light reflecting member 3 can be formed, for example, by finishing the inside of the dome into a spherical surface and then attaching a light diffusing sheet to the inside or applying a diffusible surface treatment.

As shown in FIG. 10, the diffuse reflection of the inner wall surface 32 has directivity. That is, the light Li incident on the inner wall surface 32 at the incident angle θi is diffusely reflected by the anisotropic light amount distribution as shown by the broken line. The amount of light Lr diffusely reflected by the inner wall surface 32 has a peak at a predetermined reflection angle θr. In this example, the incident angle θi and the reflection angle θr are equal. At this time, assuming that the radius of the spherical Si is r and the half-value angle of the light distribution that diffusely reflects while having directivity is θh, the illumination range in which the amount of light can be secured is a circle having an area of r × θh.

In the fourth embodiment configured in this way, the inner wall surface 32 having a curved shape recessed with respect to the work W faces the work W, and the light Li projected from the projector 5 onto the inner wall surface 32 is generated by the inner wall surface 32. It is diffusely reflected and irradiated to the work W. In particular, the diffuse reflection on the inner wall surface 32 has directivity. Therefore, most of the diffusely reflected light Lr can be advanced with respect to the work W, the range to be irradiated with the light Lr is appropriately expanded with respect to the work W, and the necessary and sufficient illuminance is secured. It is possible to do.

In the embodiment described above, the visual inspection device 1 corresponds to an example of the "visual inspection device" of the present invention, the work support portion 2 corresponds to an example of the "support portion" of the present invention, and the light reflecting member 3 corresponds to the light reflecting member 3. The inner wall surface 32 corresponds to an example of the "light reflecting surface" of the present invention, the mirror surface 33 corresponds to an example of the "mirror surface" of the present invention, and the projector 5 corresponds to an example of the "light reflecting member" of the present invention. The camera 61 corresponds to an example of the "camera" of the present invention, and the camera 61, the camera drive mechanism 62, and the control unit 7 cooperate with each other to correspond to the "imaging unit" of the present invention. As an example, the imaging positions Ia, Ib, and Ic correspond to an example of the "imaging position" of the present invention, and the work W corresponds to an example of the "inspection object" of the present invention.

The present invention is not limited to the above-described embodiment, and various modifications can be made other than those described above as long as the present invention is not deviated from the gist thereof. For example, the light reflecting member 3 has a circular dome shape in a plan view, but may have an elliptical dome shape in a plan view. Alternatively, the light reflecting member 3 may have a polygonal shape in a plan view.

Further, the curved shape of the light reflecting member 3 (curved shape of the inner wall surface 32) is not limited to the dome shape, and may be, for example, a tunnel shape as shown in FIG. FIG. 11 is a perspective view schematically showing a modified example of the shape of the light reflecting member. The tunnel-shaped light reflecting member 3 has a rectangular shape in a plan view.

Further, various projectors 5 can be used. For example, light Li may be projected onto the inner wall surface 32 by a projector 5 that creates an image at infinity.

Further, an array of light sources such as LEDs (Light Emitting Diodes) may be provided on a part of the inner wall surface 32 of the light reflecting member 3. In such a configuration, the work W can be irradiated with the light projected from the projector 5 and reflected by the inner wall surface 32 and the light emitted from the light source.

Further, in the embodiment shown in FIG. 9, the inner wall surface 32 does not have to be spherical.

Further, in the diffuse reflection characteristic shown in FIG. 10, the incident angle θi and the reflection angle θr may be different.

INDUSTRIAL APPLICABILITY The present invention can be used for all lighting techniques for irradiating an inspection object with light when inspecting the appearance of the inspection object.

1 ... Visual inspection device 2 ... Work support (support)
3 ... Light reflecting member 32 ... Inner wall surface (light reflecting surface)
33 ... Mirror surface 5 ... Projector 61 ... Camera (imaging unit)
62 ... Camera drive mechanism (imaging unit)
7 ... Control unit (imaging unit)
Ia ... Imaging position Ib ... Imaging position Ic ... Imaging position W ... Work (inspection object)

Claims (10)

A support part that supports the inspection object and
A light-reflecting member having a light-reflecting surface having a curved shape facing the inspection object and having a concave shape with respect to the inspection object.
A projector that projects light onto the light reflecting surface is provided.
The light projected by the projector on the light reflecting surface is reflected by the light reflecting surface and then irradiated on the inspection object.
On the light reflecting surface, a plurality of mirror surfaces that regularly reflect light are arranged.
The mirror surface is an appearance inspection device having a concave shape, a convex shape, or a planar shape that collects light projected by the projector between the mirror surface and the inspection object. Claim that the plurality of mirror surfaces are arranged so that the geometric centroids of each of the six mirror surfaces adjacent to one mirror surface are arranged at intervals of 60 degrees on the circumference centered on the geometric center of the one mirror surface. The visual inspection apparatus according to 1. The visual inspection apparatus according to claim 2, wherein the mirror surface has a regular hexagon. The visual inspection apparatus according to claim 2, wherein the mirror surface has a circular shape. Further provided with an imaging unit that captures the inspection object to be irradiated with the light reflected by the light reflecting surface by the camera while positioning the cameras at a plurality of imaging positions different from each other in the rotation direction about a predetermined axis. ,
The projector according to any one of claims 1 to 4, wherein the mirror surface that projects light among the plurality of mirror surfaces is changed according to the imaging position where the camera that images the inspection object is located. Visual inspection equipment. The visual inspection apparatus according to any one of claims 1 to 5, wherein the curved shape is a dome shape or a tunnel shape. The light reflecting member has a spherical outer wall surface and has a spherical outer wall surface.
The exit pupil of the projector is deviated from the center of the spherical shape of the outer wall surface.
The visual inspection apparatus according to any one of claims 1 to 6, wherein the support portion supports the inspection object on the opposite side of the exit pupil of the projector with respect to the center of the spherical shape of the outer wall surface. A process of projecting light from a projector onto a light reflecting surface having a curved shape that faces the inspection object and has a concave shape with respect to the inspection object.
A step of reflecting the light projected by the projector by the light reflecting surface and irradiating the inspection object with the light is provided.
On the light reflecting surface, a plurality of mirror surfaces that regularly reflect light are arranged.
The mirror surface is an illumination method having a concave shape, a convex shape, or a planar shape that collects light projected by the projector between the mirror surface and the inspection object. A support part that supports the inspection object and
A light-reflecting member having a light-reflecting surface having a curved shape facing the inspection object and having a concave shape with respect to the inspection object.
A projector that projects light onto the light reflecting surface is provided.
The light reflecting surface diffusely reflects the light projected from the projector and irradiates the inspection object.
The light reflecting surface is a visual inspection device having a directivity in which the amount of light diffusely reflected by the light reflecting surface has a peak in a predetermined direction. A process of projecting light from a projector onto a light reflecting surface having a curved shape that faces the inspection object and has a concave shape with respect to the inspection object.
The present invention comprises a step of diffusing and reflecting the light projected by the projector by the light reflecting surface and irradiating the inspection object.
The light reflecting surface is a lighting method having a directivity in which the amount of light diffusely reflected by the light reflecting surface has a peak in a predetermined direction.

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