JP2000293665A - Image input device - Google Patents

Abstract

(57) [Problem] To provide an image input device capable of receiving only diffuse reflection light from a target object without increasing its outer shape, and enabling detection of an image having a large density. A light transmitting object (9) that transmits light between a light source (7) and a target object (4), and a direction of an optical axis from the light source (7) to immediately before the light transmitting object (9) and from the light transmitting object (9) to the target object (4). By irradiating the light obliquely to the target object 4 by changing the direction of the optical axis, the camera 11 can receive only the diffusely reflected light from the uneven portion of the target object 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image input device which receives reflected light from a target object and judges whether or not the object exists.

[0002]

2. Description of the Related Art FIG.
, A light source 7 for irradiating the target object 4 with light at a predetermined incident angle θ2, a lens 8 provided on the optical axis thereof,
A detector that captures a light image as a pattern on a vertical line 31 with respect to the target object 4, for example, a camera 11 is disposed in the same housing 28, and irradiates the target object 4 with light from the light source 7, A camera 11 detects a planar object characteristic of the object 4, for example, diffuse reflection light 10 from an uneven portion on the surface. Here, the unevenness of the target object 4 causes the intensity of the diffuse reflected light 10 to be increased or decreased, and is obtained as a light and shade pattern.

However, when the incident angle θ2 for projecting light from the light source 7 to the target object 4 is set to be small, as shown in FIG. 11, the light receiving axis 31 of the camera 11 (same as the vertical line) is positive. The reflected light 30 approaches, and the specularly reflected light 30 is detected together with the diffusely reflected light 10, so that the shading due to the unevenness cannot be clearly obtained.

On the other hand, as shown in FIG. 12, when the incident angle θ3 for projecting light from the light source 7 to the target object 4 is set to be large, the light receiving axis 31 of the camera 11 and the regular reflection light 30 are separated from each other. Only the diffusely reflected light 10 is obtained without detecting the reflected light 30, and the shading due to the uneven portions is clearly obtained. However, when the light receiving surfaces of the camera 11 are at the same height, different results may be obtained if the heights are different.

However, if the incident angle θ3 from the light source 7 is set to be large, the light source 7 and the lens 8 are moved to the camera 11
13, the housing 28 becomes longer in the direction of arrangement of the light source 7 and the lens 8 (portion surrounded by a dotted line) as shown in FIG. It will be difficult to adopt such a device in a device that receives the information, for example, a labor-saving device such as an ATM, a coin automatic identification machine, a currency exchange machine, and an automatic ticket vending machine.

[0006]

SUMMARY OF THE INVENTION The present invention solves both of the above-mentioned problems, and can mainly receive diffusely reflected light from a detection object without increasing its outer shape. It is an object to provide an image input device capable of detecting an image.

[0007]

In order to achieve the above object, the present invention provides a light transmitting object disposed between a light source and a target object and transmitting light, and receiving reflected light from the target object. An image input device having a light receiving unit, wherein a direction of an optical axis from a light source to immediately before the light transmitting object is different from a direction of an optical axis from the light transmitting object to the target object, and the target object and the light It is provided with adjusting means for adjusting the distance between the transmissive objects.

In this configuration, even if the light source is arranged at the same position as in the conventional example, the object can be more obliquely illuminated, and only the light reflected and diffused from the uneven portion of the object can be detected by the light receiving means. Thus, the size of the device can be reduced.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show an image input device according to a first embodiment. The housing 1 is composed of a fixed base 2 and a moving body 3. The moving body 3 is slidably inserted into the fixed base 2, and is provided below the fixed base 2 for movably placing a target object 4. A space 5 is formed, and two sets of light sources 7 for irradiating the target object 4, two sets of lenses 8 arranged on the optical axis of the light source 7,
From the light source 7 to the target object 4 through a large incident angle θ
An object 9 that refracts and transmits light so as to project with 4.
(Hereinafter, referred to as a light-transmitting object), and a camera 11 that receives the diffuse reflected light 10 from the target object 4 is mounted.

The light source 7 is mounted on the moving body 3 so that its optical axis is parallel to the moving direction of the moving body 3. For example, when the moving body 3 is moved in the up-down direction, the optical axis of the light source 7 is arranged vertically.

As the lens 8, for example, a collimator lens 8 that converts light from the light source 7 into parallel light is used. The lens 8 is mounted on the moving body 3 such that the optical axis of the light source 7 coincides with the optical axis of the lens 8. The light source 7 and the lens 8 may be separately mounted on the inner wall of the moving body 3, or the light source 7 and the lens 8 may be unitized and the unitized object may be mounted on the inner wall of the moving body 3. . The unitization is advantageous because the optical axes of the light source 7 and the lens 8 are easily aligned. Alternatively, the light source 7, the lens 8, and the camera 11 may be attached to the fixed base 2, and only the light transmitting object 9 may be attached to the moving body 3.

The light-transmitting object 9 is, for example, a prism having a resolution to increase the incident angle of the outgoing light to the target object 4 with respect to the incident angle of the incident light to the object.
The prism of this embodiment has a truncated cone shape or a wedge shape. The light transmitting object 9 moves with the movement of the moving body 3 by operating the adjusting means 6.

The adjusting means 6 has an adjusting knob 61 rotatably inserted into a hole penetrated through the fixed base 2, a gear 12 fixed to one end of a protruding shaft of the adjusting knob, and an adjusting means 6 inside the moving body 3. A large number of sawtooth-shaped grooves 14 are formed, the gears 12 mesh with the grooves 14, and the moving body 3 is moved and adjusted in accordance with the turning operation of the adjustment knob 61.
It is more preferable to provide a lock means for preventing the movable body 3 from freely descending.

According to the present embodiment, since the distance between the target object 4 and the apparatus can be adjusted, only the diffusely reflected light from the concave and convex portions of the target object 4 can be more remarkably detected.

Various arrangements of the light source 7 and the light transmitting object 9 provided on the moving body 3 are conceivable. Hereinafter, various embodiments will be described.

FIG. 3 shows a second embodiment. In this embodiment, a normal prism 15 composed of a right-angled isosceles triangle is used as the light transmitting object. One light source 7 in the moving body 3, a lens 8 on the optical axis directed downward from the light source 7, and a right-angled isosceles triangular prism having a base of the right-angled isosceles triangle as a light receiving surface of light from the light source 7 Reference numeral 15 is provided on the optical axis of the light source 7, and the camera 11 is mounted such that the light receiving axis of the camera 11 that receives the diffuse reflected light 10 from the target object 4 is parallel to the optical axis of the light source 7. . The adjusting means is not shown.

According to the present embodiment, light can be irradiated to the target object 4 at a large incident angle in a limited outer shape, so that it is possible to detect only the diffuse reflection from the uneven portion of the target object 4. As a result, the unevenness information of the target object 4 can be obtained in a remarkable shade by the imaging of the camera 11. In addition, the overall shape can be reduced in size.

FIG. 4 shows a third embodiment. In this embodiment,
The moving body 3 serves as a cover for covering the entire apparatus, and a light source 7, a lens 8, a wedge-shaped prism as a light transmitting object 9, and a light receiving surface of the camera 11 are mounted inside the cover along an optical axis directed downward from the light source 7. Have been. A light source 7 near the camera 11;
Since the lens 8 and the prism as the light transmitting object 9 can be arranged, the outer shape can be reduced in size, and the object 4
Irradiates light at a large angle of incidence.

According to the present embodiment, since the moving body 3 has the cover, intrusion of dust and the like can be prevented.
Since the cover and the prism as the light transmitting object 9 are integrated, the number of parts can be reduced.

FIG. 5 shows a fourth embodiment. In this embodiment,
A plurality of light sources 7 are arranged in a ring shape, and a prism 15 having a right-angled isosceles triangle is used as a light transmitting object. Lens 8 and prism 1 for each light source 7
The arrangement of 5 is the same as described above. When the cover 3 as the moving body 3 and the prism 15 are integrated, the prism 15 is covered with a cover member 3 'as shown in FIG.

According to the present embodiment, since the plurality of light sources 7 are arranged in a ring shape, light can be projected from the target object 4 from many directions, and the prism 15 and the like are moved together. Only the diffusely reflected light 10 due to the uneven portions can be more remarkably detected.

FIGS. 7 to 9 show a fifth embodiment. In this embodiment, the image input device is applied to a coin discriminator. In FIG. 7, the coin discriminating machine 17 transfers coins inserted from the coin insertion slot 18 to the coin transport conveyor 2.
3, and the image input device 19 identifies the authenticity of the coin and the currency unit. When it is determined that the coin conveyed is fake based on the identification signal from the image input device 19, the coin is moved to the fake coin transport conveyor 24 and stored in the fake coin storage unit 21, while the coin is transferred to the fake coin storage unit 21. If it is determined that there is, the currency unit is determined, the coin is moved to the coin transport conveyor 25 for each currency unit, and stored in the storage unit 20 partitioned for each currency unit.

Storage unit 20 divided for each currency unit
Is provided with a weighing scale, a detection signal of the weighing scale for each currency unit is transmitted to a control device (not shown), and the weight is divided by a unit weight per sheet for each currency unit stored in the control device. Then, the number of sheets per pass unit is calculated, and the number of sheets per currency unit is displayed on the display panel 22 as shown in FIG.

The image input device 19, as shown in FIG.
It has a configuration equivalent to that of the first embodiment. In the image input device 19, light from the light source 7 arranged in a ring shape on the uneven portion on the surface of the coin 16 is irradiated through the lens 8 and the prism as the wedge-shaped light transmitting object 9,
The diffuse reflection light 10 reflected from the camera 6 is captured by the camera 11 to obtain shading caused by strong diffuse reflection light at the convex portion and weak diffuse reflection light at the concave portion. The unit is identified.

According to the coin automatic discriminator according to the present embodiment, since the irregularities on the coin surface are observed, it is possible to identify whether the coins are genuine or not even if they have the same size and weight, without contacting the type of coins. Can be.

[0026]

According to the image input apparatus of the present invention, the direction of the optical axis from the light source to immediately before the light-transmitting object and the direction of the optical axis from the light-transmitting object to the target object are made different from each other without increasing the outer shape. , Can irradiate the target object more obliquely,
Therefore, it is possible to detect only the diffuse reflection light from the concave and convex portions of the target object, to obtain image data with high density, and to reduce the size of the apparatus.

[Brief description of the drawings]

FIG. 1 is a front view of an image input device according to a first embodiment of the present invention.

FIG. 2 is a side view of the same device.

FIG. 3 is a front view of an image input device according to a second embodiment.

FIG. 4 is a front view of an image input device according to a third embodiment.

FIG. 5 is a front view of an image input device according to a fourth embodiment.

FIG. 6 is a perspective view of a prism in the embodiment.

FIG. 7 is a configuration diagram of a coin automatic identification machine according to a fifth embodiment.

FIG. 8 is a configuration diagram of an image input device used in the coin automatic identification machine.

FIG. 9 is a plan view showing a display example of a panel of the coin automatic identification machine.

FIG. 10 is a configuration diagram of a conventional image input device.

FIG. 11 is a diagram showing reflected light from a target object when the incident angle is small.

FIG. 12 is a diagram showing reflected light from a target object when the incident angle is large.

FIG. 13 is a configuration diagram when a large angle of incidence is used in the conventional device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 2 Fixed base 3 Moving body 4 Target object 6 Adjusting means 7 Light source 9 Light transmitting object 11 Camera (light receiving means) 15 Prism (Light transmitting object)

 ────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Hayami Hosokawa 10th Hanazono Todocho, Ukyo-ku, Kyoto-shi, Japan F-term in Omron Corporation (reference) 3E002 AA04 BD05 EA01 3E041 AA10 BA11 BA20 BB03 BC06 EA01 5B047 AA30 BA02 BB06 BC05 BC12 BC30

Claims (1)

[Claims] 1. An image input apparatus comprising: a light transmitting object disposed between a light source and a target object that transmits light; and a light receiving unit that receives light reflected from the target object. Adjusting means for adjusting the distance between the target object and the light transmitting object by making the direction of the optical axis immediately before the transmitting object different from the direction of the optical axis from the light transmitting object to the target object; An image input device characterized by the above-mentioned.