JP7079665B2 - Light irradiation device and pinhole member - Google Patents

Description

The present invention relates to a light irradiation device and a pinhole member that are suitably used for product inspection, mark detection, and the like.

Conventionally, when the surface of a product (work) is inspected, the surface of the work is irradiated with light by using, for example, the dome-shaped light irradiation device described in Patent Document 1. In this type of light irradiation device, a peephole is formed in the body of the work so that the surface of the work can be photographed by an external camera. When inspecting a work having a glossy surface using such a light irradiation device, the peephole may be reflected in the work, which may adversely affect the inspection.

In order to reduce the reflection of the peephole on the work, for example, in Patent Document 2, the lens of the camera is a pinhole lens, and the pinhole lens is used to close the peephole to take a picture of the work. The image detection unit is disclosed.

However, in the camera included in this image detection unit, the pinhole lens and the camera body are integrated, and a general-purpose camera cannot be applied instead. Therefore, in order to inspect with a camera whose specifications differ depending on the type of work, etc., it is necessary to prepare a camera in which the pinhole lens and the camera body are integrated for each inspection, which is costly and time-consuming. ..

Japanese Unexamined Patent Publication No. 2004-184241 Special Table 2009-538737 Gazette

The present invention has been made in view of such a problem, and is a light irradiation device capable of reducing reflection of a peephole in a work and to which various types of general-purpose image pickup devices can be applied, and the light irradiation. Providing a pinhole member used in an apparatus is the main intended task thereof.

That is, the light irradiation device according to the present invention is provided between the image pickup device and the work, and irradiates the work with light, and has a first light emission surface that emits light to the work and the above. A main body having an opening formed on the first light emitting surface, and a plate-shaped pinhole member arranged so as to close the opening and through which a pinhole through which the reflected light from the work passes passes in the thickness direction. The pinhole member has a mounting portion on one surface side or a side peripheral portion thereof to which the image pickup device is mounted, and the other surface of the pinhole member emits light to the work. It is characterized by being a second light emitting surface.

With such a configuration, the pinhole member closes the opening of the first light emitting surface, and the pinhole having a smaller hole diameter than the opening is used as a peephole for the image pickup device, so that the surface of the work is formed. Even if it has gloss, it is possible to reduce the reflection of the peephole on the work.
Further, since this pinhole member has an attachment portion to which the image pickup device is attached, any image pickup device having a predetermined structure attached to the attachment portion can be attached even if it has different specifications. Therefore, various types of general-purpose imaging devices can be applied depending on the type of inspection target and the like.
Further, simply by attaching the image pickup device to the attachment portion of the pinhole member, the lens of the image pickup device can be easily positioned with respect to the pinhole.
Further, since the surface of the pinhole member on the work side is the second light emitting surface that emits light to the work, it is possible to irradiate the work with light substantially uniformly from almost all directions except the back side. can.

As an embodiment of the light irradiation device, the mounting portion may be mounted by engaging the lens barrel of the image pickup device. As an example, the mounting portion is a recess formed on one surface side of the pinhole member, and the lens barrel engages with the inner surface or the outer surface of the recess.
If it is such a thing, the image pickup apparatus can be surely attached to the attachment part.

When the image pickup device is attached to the mounting portion, the tip of the lens barrel of the image pickup device is located on the work side of the opening of the pinhole formed on one surface of the pinhole member. Is preferable.
With such a device, when the image pickup device is attached to the mounting portion, the distance between the lens of the image pickup device and the pinhole of the pinhole member can be shortened, and the angle of view of the image pickup device can be widened. As a result, the amount of light taken into the image pickup device can be increased, and a brighter image can be taken.

In order to make it possible to attach different image pickup devices to one pinhole member, the attachment portion may be configured so that the image pickup device can be attached and detached.

It is preferable that the pinhole member is detachably attached to the main body.
With such a configuration, the pinhole member according to the present invention can be attached to a light irradiation device of a type having an opening in the first light emission surface, so that the light irradiation device already owned by the user can be attached. Or, it can be easily attached to a ready-made light irradiation device.

Further, the pinhole member may be integrally provided on the main body.
In such a case, the position of the pinhole with respect to the first light emitting surface of the main body can be determined in advance, so that it is not necessary for the user to position the pinhole member by himself / herself.

As an embodiment of the light irradiation device, a light source that emits light to the first light emission surface and the second light emission surface is further provided, and the first light emission surface and the second light emission surface are from the light source. Examples thereof include those that diffuse and reflect the emitted light.

According to the present invention configured as described above, the reflection of the peephole on the work can be reduced, and various types of general-purpose imaging devices can be applied.

The cross-sectional view which shows typically the whole structure of the light irradiation apparatus of this embodiment. The cross-sectional view which shows the disassembled state of the structure of the light irradiation apparatus of this embodiment. A perspective view and a cross-sectional view schematically showing the configuration of the pinhole member of the same embodiment. A perspective view and a cross-sectional view schematically showing the configuration of a pinhole member of another embodiment. A perspective view and a cross-sectional view schematically showing the configuration of a pinhole member of another embodiment. Schematic diagram comparing the distance between a pinhole and a lens. The cross-sectional view which shows typically the whole structure of the light irradiation apparatus of another embodiment. A perspective view and a cross-sectional view schematically showing the configuration of a pinhole member of another embodiment.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The size and positional relationship of the members shown in each drawing may be exaggerated for the sake of clarity.

The light irradiation device 100 according to the present embodiment is used for surface inspection of an object (work) such as a product in a factory or the like. As shown in FIG. 1, the light irradiation device 100 is a dome-shaped illumination provided between the work W and the image pickup device M to irradiate the work W with light. Then, the light reflected by the work W is captured by the image pickup apparatus M, the work W is imaged, and the surface inspection of the work W is performed.

Specifically, the light irradiation device 100 has a main body 1 having a first light emitting surface 11a that emits light to a work W arranged at a predetermined position, and light attached to the main body 1 on the first light emitting surface 11a. It is provided with a light source 2 for emitting light and a pinhole member 3 detachably attached to the main body 1.

The main body 1 has a hemispherical shape when viewed from the outside, and a hemispherical recess 11 that opens at the bottom surface thereof is formed. In the present embodiment, the first light emitting surface 11a is the inner surface of the recess 11. A white paint is applied to the inner surface of the recess 11, and the first light emitting surface 11a diffusely reflects the light from the light source 2 and functions as a so-called secondary light source.

As shown in FIG. 2, the main body 1 is formed with a through hole 13 that penetrates axially from the top of the inner surface of the recess 11 to the outer surface 12. Circular openings 13a and 13b are formed in the central portions of the first light emitting surface 11a and the outer surface 12 by the through holes 13, respectively.

The light source 2 includes a plurality of LEDs 21 (light emitting diodes) provided in one row or a plurality of rows along the inner peripheral surface of the recess 11 in the vicinity of the open end of the recess 11. The light source 2 is arranged so as to emit light toward the first light emitting surface 11a.

The pinhole member 3 includes a plate-shaped body 31 through which the pinhole 311 allows a part of the light reflected by the work W to pass to the image pickup apparatus side in the thickness direction, and the plate-shaped body 31 is inside the through hole 13. Is arranged at a predetermined position and closes the opening 13a formed in the first light emitting surface 11a.

The plate-shaped body 31 has a disk-like shape, has an outer diameter substantially the same as the inner diameter of the through hole 13 of the main body 1, and fits into the through hole 13 without a gap. The pinhole 311 is formed in the central portion of the plate-shaped body 31, and opens in a circular shape on one surface 312 and the other surface 313 of the plate-shaped body 31.

The diameter d _о of the pinhole 311 on one surface 312 (hereinafter, simply referred to as the pinhole diameter) is determined so that the image pickup apparatus M can obtain a predetermined angle of view. Specifically, as shown in FIG. 1, the pinhole diameter d _о is the thickness of the plate-shaped body 31 t, the viewing diameter V, and the pinhole 311 (center position in the thickness direction of the plate-shaped body 31) and the work W. The distance to the observation surface is set to WD, and the relationship of the following equation (1) is satisfied.

For example, when the main body 1 has general-purpose specifications (t = 2 mm, WD = 100 mm), the pinhole diameter d _о is represented by the following equation (2).

The field of view diameter V is arbitrarily set according to the shape of the work W and the main body 1. In the present embodiment, the diameter at the open end of the recess 11 of the main body 1 is the maximum value of the visual field diameter V. Therefore, when the diameter at the open end of the recess 11 of the main body 1 is twice the distance WD (that is, 200 mm), the maximum value of the pinhole diameter d _о is 2 mm.

The other surface 313 of the plate-shaped body 31 is a second light emitting surface that emits light to the work W. Like the first light emitting surface 11a, the second light emitting surface 313 is coated with a white paint and functions as a so-called secondary light source that diffusely reflects the light from the light source 2.

In a state where the plate-shaped body 31 is arranged at a predetermined position in the through hole 13, the second light emitting surface 313 and the first light emitting surface 11a are continuous without a gap, whereby light is continuously emitted. An injection surface is formed.
There may be a gap between the first light emitting surface 11a and the second light emitting surface 313.

The pinhole member 3 further has a positioning portion 32 that determines the position of the plate-shaped body 31 in the through hole 13. Specifically, the pinhole member 3 has a flange 321 extending in the radial direction from the outer peripheral surface 314 of the plate-shaped body 31. The positioning portion 32 is formed by the back surface 321a (the surface on the second light emitting surface 313 side) of the flange 321 and the outer peripheral surface 314 of the plate-shaped body 31.

The outer diameter of the flange 321 is larger than the diameter of the opening 13b on the outer surface 12 of the main body 1. When the plate-shaped body 31 is inserted into the through hole 13, the back surface 321a abuts on the outer surface 12 and the through hole 13 is formed. The axial position of the plate-shaped body 31 within is determined. Further, the outer peripheral surface 314 of the plate-shaped body 31 comes into contact with the inner peripheral surface 13c of the through hole 13 with almost no gap, and is firmly fixed without shifting in the radial direction, and the diameter of the plate-shaped body 31 in the through hole 13 is formed. The position of the direction is determined.

Therefore, the pinhole member 3 of the present embodiment has a mounting portion 33 on one surface 312 side of the plate-shaped body 31 to which the image pickup apparatus M can be detachably attached without play. The mounting portion 33 is a recess formed on one surface 312 side of the plate-shaped body 31, and the tip end portion of the lens barrel of the image pickup apparatus M is engaged with and mounted on the inner surface of the recess. ing.

In the present embodiment, a convex annular member 331 coaxial with the plate-shaped body 31 is provided on one surface 312 of the plate-shaped body 31 so as to surround the opening of the pinhole 311. The recess, which is the mounting portion 33, is formed by the inner peripheral surface 331a of the annular member 331 and one surface 312 of the plate-shaped body 31. The inner diameter of the annular member 331 is substantially the same as the outer diameter of the lens barrel of the image pickup device M, and when the lens barrel of the image pickup device M is attached to the mounting portion 33, the outer peripheral surface of the lens barrel becomes the inner circumference of the mounting portion 33. It engages with the surface and is firmly fixed without shifting in the radial direction of the lens barrel. At this time, the tip of the lens barrel comes into contact with one surface 312 of the plate-shaped body 31.

According to the light irradiation device 100 of the present embodiment configured as described above, the pinhole member 3 closes the opening 13a of the first light emitting surface 11a, and the pinhole 311 having a smaller hole diameter than the opening 13a is formed. Since the peephole is used for shooting, for example, even if the surface of the work W has a gloss, the reflection of the peephole on the work W can be reduced. Further, since the pinhole member 3 has a mounting portion 33 to which the image pickup device M can be detachably attached, even if the pinhole member 3 has different specifications, it can be attached to the mounting portion 33. Therefore, various types of general-purpose imaging devices M can be applied depending on the type of inspection target and the like. Further, since the image pickup device M can be attached to the pinhole member 3 without play, the lens of the image pickup device M can be easily and accurately positioned with respect to the pinhole 311 simply by attaching the image pickup device M to the attachment portion 33. be able to. Further, the surface of the plate-shaped body 31 on the work side emits light to the work W, and the second light emitting surface 313 and the first light emitting surface 11a of the plate-shaped body 31 are continuous. Since it is formed in, it is possible to irradiate the work W with light substantially uniformly from almost all directions except the back side.

Further, since the pinhole member 3 is of a type that can be detachably attached to the main body 1, it can be attached to a light irradiation device 100 of a type having an opening in the first light emission surface 11a. For example, it can be easily attached to a light irradiation device 100 already owned by the user or a ready-made light irradiation device 100.

The present invention is not limited to the above embodiment.

In another embodiment, as shown in FIG. 4, the recess, which is the mounting portion 33, is the inner peripheral surface or the outer peripheral surface of the annular groove 332 formed on one surface 312 of the plate-shaped body 31 so as to surround the pinhole 311. It may be formed from a surface and its bottom surface. In this case, the tip end portion of the lens barrel of the image pickup apparatus M fits into the annular groove 332, fits into the inner peripheral surface or the outer peripheral surface thereof, and is fixed without play.

In addition, a plurality of annular grooves (here, two) 3321 and 3322 having different diameters formed concentrically may be formed on one surface 312. If it is such a thing, it is possible to replace and use a plurality of types of image pickup devices having different diameter lens barrels for one pinhole member 3.

Further, as shown in FIG. 5, the concave portion of the mounting portion 33 may be an annular shape formed on the outer edge of one surface 312. In this case, the mounting portion 33 is composed of an outer peripheral surface 333a of the annular recess 333 and a bottom surface 333b thereof. Even in such a case, the tip end portion of the lens barrel of the image pickup apparatus M is fitted to the outside of the annular recess 333, and is fitted and attached to the outer peripheral surface 333a thereof.

In the pinhole member 3 shown on the right side of FIGS. 4, 5 and 6, when the image pickup apparatus M is attached to the attachment portion 33, the tip of the lens barrel of the image pickup apparatus M is a pin formed on one surface 312. It is located on the work side of the opening of the hole 311. In such a case, as shown in FIG. 6, the mounting portion 33 is formed by one surface 312 of the plate-shaped body 31 and the inner peripheral surface 331a of the annular member 331 (left side in FIG. 6). The distance between the lens of the image pickup apparatus M and the pinhole 311 may be reduced by the depth of the recess as the mounting portion 33 (that is, one surface 312 has entered the inside of the lens barrel). can. As a result, the angle of view of the image pickup apparatus M can be widened, the amount of light captured by the image pickup apparatus M can be increased, and a brighter image can be taken.

The pinhole 311 of the above embodiment is formed so that the diameter on the side of one surface 312 and the diameter on the side of the second light emitting surface 313 are substantially the same, but the present invention is not limited to this. As shown in FIG. 4, it may be formed in a tapered shape in which the diameter increases from one surface 312 side to the second light emission surface 313 side. In this case, it is preferable to apply a white paint to the inner surface of the pinhole 311 to function as a light emitting surface. Further, as shown in FIG. 5, the diameter may be tapered from one surface 312 side toward the second light emission surface 313 side.

In the above embodiment, one pinhole 311 is formed in the plate-shaped body 31, but a plurality of pinholes 311 may be formed.

In the above embodiment, the pinhole member 3 is removable from the through hole 13 of the main body 1, but may be fixed to the main body 1 with an adhesive or the like. Further, as shown in FIG. 7, it may be provided integrally with the main body 1.

In the above embodiment, the plate-shaped body 31 is arranged in the through hole 13 and thereby closes the opening 13a, but is not limited to this, and is arranged on the outer surface 12 of the main body 1 so as to cover the through hole 13. Thereby, the opening 13a may be closed.

Further, in a state where the plate-shaped body 31 is inserted into the through hole 13, there may be a gap between the outer peripheral surface 314 of the plate-shaped body 31 and the inner peripheral surface 13c of the through hole 13. Even in such a case, the radial position of the plate-shaped body 31 in the through hole 13 can be roughly determined.

The cross-sectional shape of the inner side surface (or outer side surface) of the mounting portion 33 may be different from the cross-sectional shape of the outer side surface (or inner side surface) of the lens barrel of the image pickup apparatus M. Further, the pinhole 311 of the above embodiment has a circular opening formed on one surface 312 and the other surface 313 of the plate-shaped body 31, but as shown in FIG. 8, for example, a slit-shaped opening is formed. May be. In addition, the opening shape may be an elliptical shape, an elongated hole shape, a rectangular shape, or another polygonal shape. Further, openings having different shapes may be formed on one surface 312 and the other surface 313.

In the above embodiment, the mounting portion 33 is configured such that the lens barrel of the image pickup apparatus M is mounted without play, but is not limited to this, and is mounted with a gap between the mounting portion 33 and the lens barrel. You may. Even in such a case, the position of the image pickup apparatus M with respect to the pinhole 311 can be roughly aligned. Further, by pressing the lens barrel of the image pickup device M against the mounting portion from a predetermined direction, the image pickup device M may be positioned more accurately with respect to the pinhole 311.

In another embodiment, the mounting portion 33 may be configured to mount the image pickup apparatus M using a screw structure. Specifically, a spiral groove is formed on the inner surface (or outer surface) of the concave portion of the mounting portion 33, and the spiral groove is formed on the outer surface (or inner surface) of the lens barrel of the image pickup apparatus M in this spiral groove. Fits in. Further, the image pickup apparatus M attached to the attachment portion 33 may be adhesively fixed by, for example, an adhesive or the like.

In the above embodiment, the white paint is applied to the inner surface of the recess 11 of the main body and the second light emitting surface 313 of the plate-shaped body 31, but the present invention is not limited to this. For example, these surfaces may be mirror-finished such as electrolytic polishing. Further, the main body 1 may be a light guide member, and the light from the light source 2 may be guided from the periphery of the main body 1 to emit light.

In the above embodiment, the through hole 13 of the main body 1 is formed so as to penetrate in the axial direction from the top of the inner surface of the recess 11 to the outer surface 12, but the present invention is not limited to this. The through hole 13 may be formed so as to penetrate the main body 1 along a direction perpendicular to the surface from a surface other than the top of the inner surface of the recess 11, for example. Further, as shown in FIG. 7, a plurality of (here, two) through holes 13 may be formed in the main body 1, and in this way, the work W can be photographed from a plurality of positions.

In the light irradiation device of the above embodiment, the main body 1 is a so-called dome-shaped illumination, but the present invention is not limited to this. The light irradiation device 100 may have an opening formed in the light irradiation surface 11a, and may be, for example, a light irradiation surface 11a formed in a plane and an annular shape or a rectangular shape.

In the above embodiment, the first light emitting surface 11a and the second light emitting surface 313 are secondary light sources that receive light from the light source 2 and emit light, but the present invention is not limited thereto. For example, an LED may be provided so that the first light emitting surface 11a and the second light emitting surface 313 are primary light sources that emit light by themselves.

In the above-described embodiment, the plate-shaped body 31 has a disc-shaped shape, but in addition to this, an elliptical shape, a rectangular shape, a polygonal shape, or any other shape can be adopted. Further, in the above embodiment, one surface 312 and the second light emitting surface 313 are planes parallel to each other, but the present invention is not limited to this, and the surface may not be parallel to each other or may be a curved surface. Further, the thickness does not have to be uniform, and a portion having a large thickness and a portion having a thin thickness may be provided. Further, the length in the thickness direction may be equal to or longer than the length in the direction perpendicular to the thickness direction.

In addition, the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

100 ... Light irradiation device 1 ... Main body 11a ... Light emission surface 13a ... Opening 3 ... Pinhole member 31 ... Plate-shaped body 311 ... Pinhole 312 ... One of them Surface 313 ・ ・ ・ Second light emission surface 33 ・ ・ ・ Mounting part M ・ ・ ・ Imaging device W ・ ・ ・ Work

Claims (9)

A light irradiation device provided between an image pickup device and a work to irradiate the work with light.
A main body having a first light emitting surface that emits light to the work and an opening formed in the first light emitting surface.
A plate-shaped pinhole member that is attached to the main body so as to fit into the through hole forming the opening and through which a pinhole that allows reflected light from the work to pass through in the thickness direction is provided.
The pinhole member has a mounting portion on one of the surface side or side peripheral portions to which the imaging device is mounted.
A light irradiation device in which the other surface of the pinhole member is a second light emitting surface that emits light to the work. The light irradiation device according to claim 1, wherein the mounting portion is mounted by engaging the lens barrel of the image pickup device. The light irradiation device according to claim 2, wherein the mounting portion is a recess formed on one surface side of the pinhole member, and the lens barrel engages with the inner surface or the outer surface of the recess. When the image pickup device is attached to the mounting portion, the tip of the lens barrel of the image pickup device is located on the work side of the opening of the pinhole formed on one surface of the pinhole member. The light irradiation device according to claim 2 or 3. The light irradiation device according to any one of claims 1 to 4, wherein the mounting portion is configured so that the image pickup device can be detachably mounted. The light irradiation device according to any one of claims 1 to 5, wherein the pinhole member is detachably attached to the main body. The light irradiation device according to any one of claims 1 to 5 , wherein the pinhole member is fixedly attached to the main body. A light source that emits light to the first light emitting surface and the second light emitting surface is further provided.
The light irradiation device according to any one of claims 1 to 7, wherein the first light emitting surface and the second light emitting surface diffusely reflect the light emitted from the light source. A light irradiation device provided between an image pickup device and a work to irradiate the work with light, the main body of which is formed on a light emission surface for emitting light to the work and the light emission surface. It is applied to those having an opening, and is attached to the main body so as to fit into the through hole forming the opening, and a pinhole through which the pinhole through which the reflected light from the work passes penetrates in the thickness direction. It is a pinhole member in the shape of a pinhole.
A mounting portion to which the image pickup device is mounted is provided on one surface side or the side peripheral portion.
A pinhole member whose other surface is a light emitting surface that emits light to the work.

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