JP6117324B2 - Imaging device and illumination device - Google Patents

Description

  The present invention relates to an imaging device and an illumination device that input images such as characters and symbols written on an object and use them for pass / fail determination.

  As a method of checking whether or not the character code such as the serial number and date of manufacture written on a metal can for beverages is correctly written, generally the character symbol such as a can is imaged with a camera, and an image processing device is used. There is a method for performing pass / fail analysis.

  Patent Document 1 discloses an illuminating device capable of obtaining uniform illumination even when a variety of can bottom shapes are used when a character symbol written on a metal can or the like is read and inspected by a television camera. In this illuminating device, a bell-shaped transmissive diffuser plate is provided on the irradiated object side of the annular light source of the illuminator, and a reflective diffuser plate is provided on the opposite side of the annular light source to combine with a pinhole lens.

JP-A-9-62831

  In Patent Document 1, it is necessary to provide a bell-shaped transmissive diffuser plate on the irradiated side of the annular light source, but the structure of the bell-shaped transmissive diffuser plate is relatively complicated. Moreover, an annular light source is necessary for the light source. For this reason, a lighting device having a simplified structure and an imaging device using the lighting device have been desired.

  The present invention is an invention for solving the above-described problems, and provides an imaging device and an illumination device that give a uniform illuminance to a subject and obtain a clear image such as characters written on the subject. Objective.

In order to achieve the above object, an imaging apparatus according to the present invention is an imaging apparatus that irradiates a subject such as a metal can and images reflected light thereof, and includes an imaging unit (for example, a camera 4) and an imaging unit. A lens part (for example, the lens 4a) provided on the optical axis incident optical path side and an annular disk part provided between the lens part and a subject such as a metal can and having an opening at the center part The light guide plate (for example, the light guide plate 54) having a reflection surface (for example, the surface 54a) for reflecting the light passing through the disk portion to the subject side, and the light guide plate and the subject are disposed between the light guide plate and the subject. Is provided so as to project from the peripheral edge of the opening toward the subject side, and on the axis passing through the center of the optical axis incident optical path of the imaging unit, a point located between the light guide plate and the imaging unit is apex ( For example, the conical outer peripheral surface (for example, the surface 53a) and the inner periphery, which are point B1) (E.g., the surface 53c) transparent type optical diffusion portion of the annular with (e.g., a third transparent type light diffusing portion 53) and a light source arranged outside the radial direction of the disk portion (e.g., a light source 22) and, the The transparent light diffusing unit is viewed from a side cross section, the angle formed by the outer peripheral surface sharing the apex is an obtuse angle, and the angle formed by the inner peripheral surface sharing the apex is narrower than the angle formed by the outer peripheral surface characterized in that there.

Imaging device is further arranged substantially perpendicular to the optical axis incident light path of the imaging unit, a second imaging unit that captures an image of a side surface of an object permeable Akirakatachi light diffusing portion (e.g., a camera 4S), the second And a second lens unit (for example, a lens 4Sa) provided on the optical axis incident optical path side of the imaging unit.

  According to the present invention, a uniform illuminance can be given to a subject, and a clear image such as characters written on the subject can be obtained.

It is a figure which shows the test | inspection apparatus containing the illuminating device which concerns on this embodiment. It is a figure which shows the structure of an illuminating device among the whole structures shown in FIG. It is the figure which expanded the illuminating device shown in FIG. It is a figure which shows the relationship between a light source and a transmission type diffuser plate. It is a figure which shows the example of an imaging of a can bottom part. It is a figure which shows the case where an imaging part is arrange | positioned on the side surface of a to-be-photographed object. FIG. 7 is a diagram illustrating an arrangement configuration for various subjects in FIG. 6. It is a figure which shows the example of an imaging of a bottle cap. It is a figure which shows the other structure of an imaging device. It is a figure which shows the basic structure of a light-guide plate. It is a figure which shows the example of an imaging of a bottle cap. It is a figure which shows the case where a syringe is imaged using the imaging device of FIG. It is a figure which shows the example of an imaging of a syringe. It is a figure which shows the case where a seaming panel is imaged using the imaging device of FIG. It is a figure which shows the example of an imaging of a seaming panel.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram illustrating an inspection apparatus including an illumination apparatus according to the present embodiment. FIG. 1 shows an example of the overall configuration when the illumination device according to the present embodiment is applied to, for example, a character / symbol inspection device written on the bottom 11 of the can 1. In order to inspect the characters and symbols written on the can bottom 11 of the can 1 conveyed on the conveyor 3, the illumination device 2 is disposed above, and further through the center hole 25 a of the illumination device 2, the can 1 is A lens 4 a is attached to a camera 4 such as a CCD (Charge Coupled Device) camera so that the can bottom 11 can be imaged. The imaging device 40 includes the camera 4, the lens 4a, the illumination device 2, and the like.

  The sensor 5 generates a detection signal at the moment when the can 1 passes almost directly under the illumination device 2 and the camera 4, and this detection signal activates the illumination power source 2 a via the image processing device 6 to emit light from the illumination device 2. The can bottom 11 of the can 1 is irradiated. At the same time, the video signal of the camera 4 is input to the image processing device 6 in synchronization with the detection signal. The image processing device 6 performs a predetermined analysis process from the video signal to determine pass / fail, and rejects defective products by the sorting mechanism 7.

  FIG. 2 is a diagram showing the structure of the illumination device in the overall configuration shown in FIG. FIG. 3 is an enlarged view of the illumination device shown in FIG. The camera 4 and the lens 4a, the illumination device 2, and the can 1 are arranged as shown in the figure. A lighting device 2 is disposed below the lens 4a, and a can 1 as a subject is disposed below the lighting device 2. The illuminating device 2 has a reflection type diffusion plate 25 disposed on the lens 4a side, and an annular second transmission type diffusion plate 24 and an annular first transmission type diffusion plate are provided below the reflection type diffusion plate 25. 23 is arranged. Details will be described later. Note that broken and solid arrows indicate examples of optical paths.

  The illuminating device 2 stores an LED (Light Emitting Diode) as a light source 22 in a light shielding house 21 of a main body frame. The light-shielding house 21 has a first transmission type diffusion plate 23 and a second transmission type diffusion plate 24 having an opening at the center. A reflective diffusion plate 25 is disposed on the upper side of the light shielding house 21. Hereinafter, although the transmission type diffuser plate is configured by a plurality of surfaces, the side close to the central axis is the inner surface, and the side away from the central axis is the outer surface.

  The annular first transmission type diffusion plate 23 has six surfaces 23a, 23b, 23c, 23d, 23e, and 23f. The outer surfaces of the surfaces 23a, 23d, 23e, and 23f are white surfaces so as to be easily reflected. In addition, you may arrange | position a white reflector on the outer surface side of the surfaces 23a, 23d, 23e, and 23f. The surface 23d of the first transmission type diffuser plate 23 basically has a conical surface with the point B on the central axis as a vertex. The setting of the point B is preferably set so that the surface 23d becomes a reflection surface in which the reflected light is directed to the center of the can bottom 11 of the can 1 as the subject.

  Specifically, the path emitted from the light source 22 will be described. The irradiation light 22a from the light source 22 is reflected by the surface 23a to become reflected light 22b. The reflected light 22b is reflected by the inner surface of the surface 23b to become reflected light 22c. The reflected light 22c is reflected by the inner surface of the surface 23c to become reflected light 22d. The reflected light 22d is reflected by the inner surface of the surface 23d to become reflected light 22e, and is irradiated on the can bottom 11. Further, the irradiation light 22g from the light source 22 is reflected by the surface 23e to become reflected light 22h. The reflected light 22h is transmitted and refracted through the surface 23b to become refracted light 22i. Further, the irradiation light 22p from the light source 22 is transmitted and refracted by the surface 23b to become refracted light 22q.

  The annular second transmissive diffusion plate 24 is composed of eight surfaces in the figure, but has surfaces 24a, 24b, 24c, and 24d as main surfaces related to the optical path. The outer surface of the surface 24d is a white reflecting surface so as to be easily reflected.

  The optical path in the second transmissive diffusion plate 24 will be described in detail. The refracted light 22i is reflected by the surface 24a to become reflected light 24i, and is refracted through the surface 24c to become refracted light 24j. The refracted light 24j is reflected by the reflective diffusion plate 25 to become reflected light 24k and irradiates the can bottom 11. The refracted light 22i is transmitted and refracted by the surface 24a to become refracted light 24m.

  The material of the first transmission type diffusion plate 23 and the second transmission type diffusion plate 24 may be a transparent light guide material made of glass or resin.

  The reflection type diffuser plate 25 is disposed above the central axis of the light shielding house 21, and the position thereof can be adjusted by changing the thickness of the distance piece 26, for example. For example, the thickness of the distance piece 26 may be changed so as to contact the lens 4a so that light other than the illumination device 2 does not enter the lens 4a. The size of the central hole 25a of the reflective diffusion plate 25 is set in a range that does not interfere with the field of view of the lens 4a. The reflective surface of the reflective diffusion plate 25 may be a satin-like reflective surface coated with a material having good reflection efficiency, such as aluminum powder, glass powder, ceramic powder, etc. from which scattered light can be obtained.

  The light source 22 is held by a holding unit 27, and the surface 27a of the holding unit 27 on the first transmissive diffusion plate 23 side is preferably a reflective surface.

  For example, the light source 22 may have a plurality of bullet-type LEDs arranged in a tubular shape outside the first transmissive diffusion plate 23, but is not limited thereto. In FIG. 4, the relationship between the light source and the transmissive diffusion plate will be described later.

  The illumination device 2 in FIG. 2 will be further described. The illuminating device 2 has a flat plate shape and has an opening (for example, a center hole 25a) at the center thereof, and an imaging unit (for example, the camera 4) is close to the opening and is opposite to the imaging unit side. A reflection-type diffusion plate 25 that is a reflection-type light diffusion plate having a reflection surface as a reflection surface, and an opening that is disposed between the reflection-type light diffusion plate and the subject to be imaged by the imaging unit and that is larger than the outer shape of the subject at the center. It has an annular disk portion (for example, a portion formed by the surfaces 23b, 23a, 23f, and 23e) provided with an opening (for example, an opening formed by the surface 23c), and extends from the periphery of the opening to the subject side. A conical portion (for example, a portion formed by the surfaces 23d, 23c, etc.) that protrudes toward the tip and has an acute-angled cross section, and a radially outer peripheral surface (for example, the surface 23d) of the conical portion is It is a reflective surface, both sides of the reflective light diffusing plate side and subject side of the disk part The surface is disposed between the first transmissive diffusion plate 23, which is a first transparent light diffusing unit, which is a reflecting surface (for example, surfaces 23a and 23e), and between the reflective light diffusing plate and the subject. A second transparent light diffusion having an opening (for example, an opening formed by the surface 24b) and a reflection surface (for example, the surface 24a) for reflecting the light passing through the disk portion to the reflective light diffusion plate side. A second transmissive diffusion plate 24 that is a portion, and a light source 22 that is disposed outside the disk portion in the radial direction.

  According to this embodiment, the entire can bottom 11 can be irradiated with light uniformly from the entire circumference, the entire can bottom 11 can be illuminated, and characters printed in black or the like can be raised.

  FIG. 4 is a diagram showing the relationship between the light source and the transmissive diffusion plate. 4 is a cross-sectional view taken along the line AA in FIG. 2 (the LED is not cross-sectional). In the example shown in FIG. 4, line light sources 22A, 22B, 22C, and 22D in which a plurality of bullet-type LEDs are arranged are arranged as a light source 22 in a rectangular shape, and a first transmission type diffuser plate 23 and a second light source 22 are arranged therein. The transmission type diffusion plate 24 is arranged. In the case of FIG. 4, it is conceivable that the luminance entering the radial direction of the first transmission type diffuser plate 23 is different. For example, when an arbitrary point a in FIG. 4 is taken as an example, light incident on the point a ( In the figure, the optical path is indicated by an arrow), and is characterized by almost no influence since it enters from a plurality of LEDs. Further, as the light source 22 shown in FIG. 4, the line light sources 22A, 22B, 22C, and 22D have the same structure and can be manufactured at a relatively low cost.

  The illuminating device 2 of the present embodiment has a flat plate shape and has an opening having a size that does not obstruct the field of view of the image pickup unit (for example, the camera 4) at the center thereof. A reflective diffuser plate 25 having a reflective surface on the surface opposite to the part side, a conical part having an opening larger than the diameter of the subject at the center and a vertex on the subject side, and the radial direction of the conical part The outer surface is a reflective surface, and has a disk-shaped disk portion extending from the conical portion on the radially outer side of the conical portion on the reflective diffuser plate 25 side, and the reflective diffuser plate 25 side of the disk portion, Both surfaces on the object side have a first transmissive diffusion plate 23 (inverted conical transparent light diffusing portion) that is a reflecting surface, and an opening having a size that does not obstruct the field of view of the imaging unit at the center. Second transmissive diffuser plate 24 having a reflective surface for reflecting light passing through the reflective diffuser plate 25 side, and the radial direction of the disk portion And it includes a light source 22 arranged outside of.

  FIG. 5 is a diagram showing an example of imaging of the bottom of the can, (a) is the case of the aluminum background of the curl can, (b) is the case of the silver of the flat bottom can, and (c) is the talc of the flat bottom can. (Registered trademark). The left column of FIG. 5 is an image of only the indoor ceiling lamp as a comparative example, and the right column of FIG. 5 is an image captured by the imaging apparatus of the present embodiment. In any of the cans shown in FIGS. 5 (a) to 5 (c), printing on the bottom of the can can be satisfactorily obtained.

  In the case of the flat bottom cans of FIGS. 5B and 5C, substantially the same image is obtained without the second transmissive diffusion plate 24 (see FIGS. 2 and 3) in the illumination device 2. Can be obtained. The second transmission type diffusing plate 24 is effective in obtaining a good image when used for imaging characters printed on a curved surface such as the curl can shown in FIGS.

  According to this embodiment, uniform scattered light is obtained from the light of the illumination device 2 by the first transmission type diffusion plate 23, the second transmission type diffusion plate 24, and the reflection type diffusion plate 25, and the irradiated object. , It is possible to input a clear image with no illumination unevenness to the camera 4. For example, by applying the illumination device 2 and the imaging device 40 to a metal can or plastic bottle character / symbol inspection device, the shape of the bottom of the can can be a variety of shapes and types, such as a concave shape and a convex shape. Therefore, the image of the character symbol can be clearly extracted and the quality of the printing can be reliably determined. In addition, a clear image can be obtained even if the printed surface and character symbols are colored.

(Application examples)
FIG. 6 is a diagram illustrating a case where the imaging unit is arranged on the side surface of the subject. Application to the inspection of character symbols on the side surface of the bottle cap 30 will be described. The bottle cap 30 of the PET bottle 1 </ b> A includes a bottle cap body 31 and a cylindrical member 32. The cylindrical member 32 is printed with a character symbol combined with the expiration date or the unique symbol of the factory. FIG. 6 shows a configuration for obtaining an image of this character symbol, in which a camera 4S (second imaging unit) having a lens 4Sa is arranged in the side surface direction (radial direction) of the bottle cap 30.

  The configuration of the illumination device 2 shown in FIG. 6 is the same as that of the illumination device shown in FIG. The surface 23d of the first transmission type diffuser plate 23 basically has a conical surface with the point B on the central axis as a vertex. In FIG. 1, the distance L between the bottle cap 30 and the lower surface of the lighting device 2 is secured and set so as not to be an obstacle when the PET bottle 1 </ b> A is conveyed by the conveyor 3.

  The imaging device shown in FIG. 6 will be described. A second imaging unit (for example, the camera 4S) that images the side surface (for example, the cylindrical member 32) of the head of the subject (for example, the plastic bottle 1A), and the second imaging. A second lens unit (for example, a lens 4Sa) provided on the optical axis incident optical path side of the unit, and the illumination device 2.

  In FIG. 6, since the camera 4 and the camera 4S are arranged facing the subject, the top surface (upper surface) of the bottle cap body 31 can be imaged by the camera 4, The printing of the cylindrical member 32 can be imaged by the camera 4S. It is preferable to arrange at least one of the camera 4 and the camera 4S according to the inspection contents.

  FIG. 7 is a diagram showing an arrangement configuration of various subjects in FIG. The subject includes the case of the plastic bottle 1A and the case of the can 1, and the size of the subject and the printing position of the bottle cap 30 are different. The bottle cap 30 is at the position shown in FIG. The bottle cap 30A is a case where the bottle cap 30A is shifted from the center line on the reflected light 22e from the position of the bottle cap 30. The bottle cap 30B is a case where the bottle cap 30B is further shifted from the center line on the reflected light 22e from the position of the bottle cap 30. In the case of side surface printing inspection, the height of illumination and the contrast on the printing side can be adjusted by shifting from the illumination center axis (dashed line), so that it is possible to cope with printing inspection of bottles of different sizes.

  FIG. 8 is a diagram illustrating an example of imaging a bottle cap, where (a) is a case of a blue bottle cap and (b) is a case of a bottle can. The left column in FIG. 8 is an image of only the indoor ceiling lamp as a comparative example, and the right column in FIG. 8 is an image captured by the imaging apparatus of the present embodiment. Printing can be satisfactorily obtained for both the subjects shown in FIGS. 8A and 8B.

  The illuminating device 2 according to this embodiment of the application example is a reflection type light diffusing having a flat plate shape on the head of the subject such as the bottle cap 30 and having an opening at the center thereof, and a surface on the subject side as a reflecting surface. A reflection-type diffusion plate 25 that is a plate, and an annular disk portion that is disposed between the reflection-type light diffusion plate and the subject and that has an opening larger than the outer shape of the subject at the center. The cone has a conical portion projecting from the peripheral portion toward the subject side and having a sharp tip at the tip, and the outer circumferential surface in the radial direction of the conical portion is a reflective surface, and the reflective light diffusion of the disc portion Surfaces on both sides of the plate side and the subject side are disposed between the first transmissive diffusion plate 23, which is a first transparent light diffusing portion that is a reflecting surface, and between the reflective light diffusing plate and the subject, And a second transparent light spreader having a reflection surface for reflecting light passing through the disk portion to the reflective light diffusion plate side. A second transmission diffusion plate 24 is a part, and a light source 22 arranged outside the radial direction of the disk portion.

  According to this embodiment of the application example, the side surface of the bottle cap 30 can be uniformly irradiated, and characters printed in black or the like on the side surface can be highlighted.

  FIG. 9 is a diagram illustrating another structure of the imaging device. The imaging device 40A includes the cameras 4 and 4S, the lenses 4a and 4Sa, the illumination device 2A, and the like. The illuminating device 2 </ b> A houses an LED, which is a light source 22, in a light shielding house 21 of a main body frame. The light-shielding house 21 has a light guide plate 54 having an opening at the center and a third transmission type diffusion plate 53 (third transparent light diffusion portion, conical transparent light diffusion portion) having an opening at the center. ing. The illuminating device 2A of the imaging device 40A has an effect that the condensing distance is longer than that of the illuminating device 2 shown in FIG.

  The annular third transmission-type diffusing plate 53 (conical transparent light diffusing portion) has seven surfaces 53a, 53b, 53c, 53d, 53e, 53f, and 53g. The surfaces 53a and 53c of the third transmission type diffusing plate 53 basically have a conical surface with the point B1 on the central axis as a vertex. The setting of the point B1 is such that the light is directed downward from the top surface (upper surface) of the bottle cap 30 of the PET bottle 1A whose subject is the surface 53a and the surfaces 53b and 53c (for example, incident light 61a, refracted light 61b, 61c) It is preferable that the setting is such that it is a transmission surface.

  The annular light guide plate 54 has four surfaces 54a, 54b, 54c, and 54d. The outer surfaces of the surfaces 54a and 54b are white reflecting surfaces so as to be easily reflected. The light guide plate 54 has a function of backlight illumination for irradiating light to the third transmission type diffusion plate 53, and the details will be described with reference to FIG.

  10A and 10B are diagrams showing the basic structure of the light guide plate, FIG. 10A is an explanatory diagram of the structure, and FIG. 10B is a diagram showing the reflective dots provided on the surface 54a. Irradiation light from the LED 22 provided on the side surface of the light guide plate 54 is reflected by the reflective dots, and the direction is changed downward as shown in FIG. 10A. As shown in FIG. 10B, the reflective dots are concave with respect to the material of the light guide plate 54 with respect to the surface 54a, and are convex with respect to the direction in which light is guided. It is preferable that the reflective dot is larger in a unidirectional manner in a saw-like shape (prism sheet or the like) or an elliptical hole as the distance from the LED 22 is increased.

  FIGS. 11A and 11B are diagrams illustrating an example of imaging of the bottle cap. FIG. 11A illustrates the case of the top surface (upper surface) of the bottle cap 30, and FIG. 11B illustrates the case of the side surface of the bottle cap 30. In the case of FIG. 11A, the image on the left side is an image of only the indoor ceiling lamp as a comparative example, and the image on the right side is an image captured by the imaging device 40A of the present embodiment. The characters on the top of the bottle cap 30 can be obtained favorably by the camera 4 of the imaging device 40A.

  In the case of FIG. 11B, the image on the left is an image of only the indoor ceiling lamp as a comparative example, and the image on the right is an image captured by the imaging device 40A of the present embodiment. The characters of the cylindrical member 32 of the bottle cap 30 can be favorably obtained by the camera 4S of the imaging device 40A. It can be identified from the image captured by the imaging device 40A that a character (for example, the character “3”) has a missing dot.

  FIG. 12 is a diagram illustrating a case where a syringe is imaged using the imaging device of FIG. 9. 13A and 13B are diagrams illustrating an example of imaging of a syringe. FIG. 13A is a normal image of the top surface of the luer lock 61 of the syringe 60 (syringe) as a subject, and FIG. 13B is a top surface of the luer lock 61. (C) is an image of the side surface of the luer lock 61.

  In the case of FIG. 13 (a), it can be seen that the center hole and the like are normal with no scratches, but in the case of FIG. 13 (b), the center hole is in a buried state. This is because silicon in the main body of the syringe 60 formed a film in the center hole.

  When the imaging device 40A is introduced into the syringe inspection line, it is turned upside down in the drawing of FIG. Using the camera 4 through a mirror arranged at 40 degrees with respect to the horizontal plane, the luer lock 61 of the syringe 60 may be photographed from below to above.

  In the case of FIG. 13C, it can be seen that a good image including the internal structure of the luer lock 61 is obtained.

  FIG. 14 is a diagram illustrating a case where the seaming panel is imaged using the imaging device of FIG. 9. In imaging, a light shielding material 56b is provided on the surfaces 53c and 53d of the illumination device 2A shown in FIG. 9 for inspection of the seaming panel. A light shielding material 56a is also provided on a part of the surface 53b.

  15A and 15B are diagrams illustrating an example of imaging a seaming panel. FIG. 15A illustrates a can lid image (left side) and an image captured by the imaging device 40A (right side) as a comparative example, and FIG. It is explanatory drawing which shows a location. The ring image on the right side of FIG. 15A is a ring image at the upper end of winding (specifically, a ring image by reflected light from the seaming panel), and a ring image is obtained satisfactorily. On the other hand, in FIG. 15B, it can be seen that there is a defect in the ring image and there is a problem. The image of this embodiment can detect a winding failure by inspecting the entire width of the ring width of the ring image of the seaming panel.

The imaging apparatus shown in FIG. 9 includes an imaging unit (for example, camera 4), a lens unit (for example, lens 4a) provided on the optical axis incident optical path side of the imaging unit, and a lens unit and a subject such as a metal can. A light guide plate 54 disposed between and having a circular disc portion provided with an opening at the center, and having a reflecting surface 54a that reflects light passing through the disc portion toward the subject, and the light guide plate 54 and the subject. Between the light guide plate 54 and the light guide plate 54 on the axis passing through the center of the optical axis incident optical path of the imaging unit. An annular third transparent light having a conical outer peripheral surface (for example, surface 53a) and an inner peripheral surface (for example, surface 53c) having a point positioned between the imaging unit and a vertex (for example, point B1). Diffusion part (for example, third transmission type diffusion plate 53) and the outer side in the radial direction of the disk part Comprising the arranged light source 22, and the third transparent form light diffusing portion in a sectional side view, an angle of the outer peripheral surface that share vertices is obtuse, the angle between the inner peripheral surface of sharing vertices The angle is narrower than the angle formed by the outer peripheral surface, and the object can be irradiated with light and the reflected light can be imaged.

  The size of the opening formed by the surface 53 shown in FIG. 9 is such that the PET bottle 1A (see FIG. 9) or the can 1 (see FIG. It means that the size is within a range that does not obstruct the visual field viewed from the lens 4a.

  The imaging device is further disposed substantially perpendicular to the optical axis incident optical path of the imaging unit, and a second imaging unit (for example, camera 4S) that images the side surface of the subject on the third transparent light diffusing unit side of the subject. And a second lens unit (for example, lens 4Sa) provided on the optical axis incident optical path side of the second imaging unit. Thereby, the side surface of the bottle cap 30 can be irradiated uniformly, and characters printed in black or the like on the side surface can be highlighted.

1 Can 1A PET bottle 2, 2A Illumination device 4 Camera (imaging part)
4a Lens (lens part)
4S camera (second imaging unit)
4Sa lens (second lens part)
5 Sensor 6 Image processing device 7 Sorting mechanism 11 Can bottom 21 Light-shielding house 22 Light source 23 First transmission type diffusion plate (first transparent light diffusion portion, inverted conical transparent light diffusion portion)
24 2nd transmission type diffuser (2nd transparent light diffusion part)
25 Reflective diffuser (reflective light diffuser)
25a Center hole (opening)
26 Distant piece 30 Bottle cap 31 Bottle cap body 32 Cylindrical member 40, 40A Imaging device 53 Third transmission type diffusion plate (third transparent light diffusing unit, conical transparent light diffusing unit)
54 Light guide plate

Claims (6)

An imaging unit;
A lens unit provided on the optical axis incident optical path side of the imaging unit;
A reflective surface that is disposed between the lens unit and a subject such as a metal can and has an annular disc part with an opening provided in the center, and reflects light passing through the disc part toward the subject side. A light guide plate having,
Arranged between the light guide plate and the subject, an opening is provided in the center, protrudes from the peripheral edge of the opening toward the subject, and the optical axis incident optical path of the imaging unit An annular transparent light diffusing unit having a conical outer peripheral surface and an inner peripheral surface with a point located between the light guide plate and the imaging unit on an axis passing through the center ;
A light source disposed outside the disk portion in the radial direction,
When the transparent light diffusing unit is viewed in a side sectional view, the angle formed by the outer peripheral surface sharing the vertex is an obtuse angle, and the angle formed by the inner peripheral surface sharing the vertex is narrower than the angle formed by the outer peripheral surface. Angle,
An imaging apparatus, wherein the subject is irradiated with light and the reflected light is imaged. The imaging device further includes:
Disposed on the optical axis incident path substantially perpendicular of the imaging unit, a second imaging unit that captures an image of a side surface of the object of the permeable Akirakatachi light diffusing portion,
The imaging apparatus according to claim 1, further comprising: a second lens unit provided on an optical axis incident optical path side of the second imaging unit. The imaging apparatus according to claim 1, characterized in that said inner peripheral surface of the light shielding surface before KiToru Akirakatachi light diffusing portion. The imaging device according to any one of claims 1 to 3, wherein the light source is an LED (Light Emitting Diode). An annular disk part that is disposed between the imaging unit and a subject such as a metal can photographed by the imaging unit and has an opening at the center part, and the light passing through the disk part is directed to the subject side A light guide plate having a reflective surface to be reflected;
Arranged between the light guide plate and the subject, an opening is provided in the central portion, protruded from the peripheral edge of the opening toward the subject , and the center of the optical axis incident optical path of the imaging unit An annular transparent light diffusing unit having a conical outer peripheral surface and an inner peripheral surface with a point located between the light guide plate and the imaging unit on an axis passing through
A light source disposed outside the disk portion in the radial direction,
When the transparent light diffusing unit is viewed in a side sectional view, the angle formed by the outer peripheral surface sharing the vertex is an obtuse angle, and the angle formed by the inner peripheral surface sharing the vertex is narrower than the angle formed by the outer peripheral surface. Angle,
An illumination device that irradiates the subject with light. The lighting device according to claim 5, wherein the light source is an LED (Light Emitting Diode).