JPH0388078A - Image input device - Google Patents

Abstract

PURPOSE:To make a system compact by arranging an image entry part, an image input part and plural lighting means for lighting up a face to be picked up at its image in a case. CONSTITUTION:A pair of lighting means 17, 17 are fixed on one corner part of the inner bottom of a rectangular parallelopiped-like case 9. Lighting beams projected upwards from respective lighting source 1 and diffused by a diffusion plate 14 to uniformly illuminate its upper image entry part 15. The lower face of a work 5 such as a coin or a medal contacted with the upper face of a cover glass 4 is set up as a face to be picked up 5a at its image. The reflected light of the face 5a is reflected to the side by a mirror 3 and forms an image on a line sensor 7 through an image forming optical system 6. The image input means 10 is constituted of the optical system 6 and the sensor 7 and the means 17, 10 and the entry part 15 area arranged in the case 9.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an image input device, for example,
This can be used to determine whether a work is correct or not, or whether it is good or bad, through image processing.

(Prior Art) For example, an image processing apparatus requires an image input device for inputting an image signal of a workpiece to the processing apparatus. An image input device basically includes a workpiece mounting section and a camera or an imaging optical system disposed opposite to a surface to be inspected of the workpiece placed on the mounting section. Figures 3 to 5 are
Various examples of conventional image input devices are shown. In both examples, the workpiece 21 is placed on the workpiece mounting section 22 with its imaged surface facing upward, and a television camera 26 having a lens 27 is placed above the workpiece 21 so that the lens 27 is placed on the workpiece 21.
It is arranged so as to face the surface to be imaged. and the third
In the illustrated example, an illumination light source 24 placed on the side of the lens 27 illuminates the imaged surface of the work 21. In the example shown in FIG. 4, the illumination light flux from the illumination light source 24 is focused on one end surface of the light guide 29 via the lens 28, and the illumination light flux guided by the light guide 29 is directed downward from around the lens 27 of the camera 26. The imaged surface of the workpiece 21 is illuminated by irradiating the object. In the example shown in FIG. 5, a half mirror 30 is installed obliquely between the lens 27 of the camera 26 and the workpiece 21, and the illumination light beam from the illumination light source 24 disposed on the side is reflected downward by the half mirror 30. to illuminate the imaged surface of the second workpiece.

(Problems to be Solved by the Invention) In any of the above image input devices, the workpiece placement section, illumination means, and image input means are individually manufactured and arranged individually, so the overall system becomes large. There is a problem,
This has led to problems such as susceptibility to interference from external light and uneven illumination, and in order to eliminate these problems as much as possible, the light source had to be strengthened.

The present invention was made to solve the problems of the conventional technology, and the entire system can be made compact, less susceptible to interference from external light, and without uneven lighting.
Moreover, it is an object of the present invention to provide an image input device that does not require strengthening the light source.

(Means for Solving the Problems) The present invention provides a case having an image capturing section for capturing an image of the imaged surface of a workpiece, and an image input means attached to the case for inputting an image of the imaged surface of the workpiece. and,
The present invention is characterized by comprising an illumination means that is installed between the image capture section and the image input means in the case and illuminates the imaged surface of the workpiece.

(Function) The illumination means installed in the case illuminates the imaged surface of the workpiece located in the image capture section provided in the case. An image of the imaged surface of the workpiece is captured by an image input means provided within the case, and is input to an image processing device or the like.

(Example) Hereinafter, an example of the image input device according to the present invention will be described with reference to the construction drawings and FIG. 2.

In FIG. 1, a pair of illumination means 17, 17 are fixed to one corner of the inner bottom of the rectangular parallelepiped case 9, separated into a front side and a back side. Lighting means f.

Each F has a plurality of light sources 1.1 and a diffuser plate 14.14 arranged above them. The light source is composed of appropriate light emitting elements, such as LEDs, and a plurality of light sources 1 are arranged in a line on the substrate. Illumination light emitted upward from each light source 1.1 is transmitted through a diffuser plate 1414.14.
The light is diffused and evenly illuminates the area above it. The number of rows of light emitting elements and the total number of light emitting elements constituting the light source 1 may be changed as appropriate depending on the size of the workpiece, its material, etc., which will be described later.

The illumination light from the pair of illumination means 17, 17 is transmitted to the diffuser plate 14.
14 and reaches the ceiling of the case 9, to which a transparent cover glass 4 is fixed.

The cover glass 4 is embedded in the window hole of the case 9 so that the top surface of the cover glass 4 coincides with the top surface of the case 9. The above cover glass 4 of case 9
The part having , is an image capturing part t5,
A workpiece 5 is conveyed over a cover glass 4 from the back toward the front in the figure. The workpiece 5 is, for example, a coin or a medal, and the lower surface of the workpiece 5 that is in contact with the upper surface of the cover glass 4 is the imaged surface 5a.

A mirror 3 is provided obliquely between the pair of illumination means 17.17. Although the mirror 3 is composed of a prism in the illustrated example, it may be of any material as long as it reflects light. The diagonal direction of the mirror 3 is such that light from above is reflected to the right in FIG.

The reflected light from the imaged surface 5 a of the workpiece 5 is reflected laterally by the mirror 3 and reaches the imaging optical system 6 . The imaging optical system 6 is
An image of the imaged surface 5a of the workpiece 5 is formed on the line sensor 7. The focus of the imaging optical system 6 can be adjusted using a focus adjustment member.

The line sensor 7 is fixed to the inner wall surface of the case 9 on the opposite side from where the illumination means 17.17 is arranged.

The line sensor 7 detects an image of the imaged surface 5a of the workpiece 5 illuminated by the illumination means 17.17 for each line in a direction orthogonal to the transport direction of the workpiece 5, and outputs it as an image signal. This image signal is input to an image processing device or the like. A portion including the imaging optical system 6 and the line sensor 7 constitutes an image input means 10.

As can be seen from the above description, the illumination means 17 and 17, the image capture section 15 and the image input device 0 are installed in one case 9, and the image capture section 15 and the image input means 10 are connected to each other. Lighting means 17.17 will be installed in between.

In this way, 11 image capturing section 15 and image input means 10
Since the lighting means 17.17 is installed between the
The illumination light from the illumination means 17.17 may directly enter the image input means 10 and deteriorate the image. Therefore, in the illustrated embodiment, a light shielding plate 1 is provided between each light source 1.1 and the mirror 3.
9.19, and a light shielding plate 18.18 is also set up between the light source 1.1 and the imaging optical system 6, so that the illumination light from the light source 1.1 directly enters the image input means 10. I try not to.

The case 9 houses all of the constituent members, and also serves to shield ambient light so that it does not affect the image signal.

Now, when illumination light is emitted from the illumination means 17.17,
The illumination light is diffused by a diffuser plate 14.14 to uniformly illuminate the image capture section 15. When the workpiece 5 is conveyed on the image capturing section 15 in this state, the imaged surface 5a of the workpiece 5 is illuminated with the illumination light, and this illumination light is reflected by the imaged surface 5a. This reflected light passes through the cover glass 4, is reflected laterally by the mirror 3, and is imaged onto the line sensor 7 by the imaging optical system 6. The line sensor 7 outputs one line at a time as an image signal of the workpiece 5 in response to the reflected light. This image signal is input to an image processing device (not shown) and is subjected to predetermined image processing such as determining whether the work is correct or defective and whether it is good or bad.

Note that the amount of light @1,1 emitted can be controlled according to the output level of the line sensor 7. Further, even when the reflectance of the imaged surface 5a differs depending on the material of the workpiece 5, the amount of light emitted from the light source 1.1 can be controlled in the same manner. As described above, it is preferable that the light source 1.1 is capable of adjusting the amount of light, and other light sources other than LEDs may be used as long as the amount of light can be adjusted.

In this way, according to the above embodiment, the image capturing section 15
, the image input means 10 and the illumination means 17 in one case 9
Since the image input device is installed in an integrated manner, it is possible to obtain an image input device that is extremely miniaturized compared to conventional image input devices. Furthermore, whereas the conventional image input device illuminates the workpiece from above, in the above embodiment, the workpiece 5 is illuminated from below from inside the case 9, so it is less affected by external light. At the same time, it becomes easier to concentrate the illumination light on the image capturing section 15.

A high output light source is no longer required.

Note that the light source l constituting the illumination means may be arranged so as to surround the mirror 3 on three sides, as shown in FIG.

Further, as the image input means, an image sensor capable of inputting a two-dimensional image signal may be used instead of the line sensor 7 in the illustrated embodiment.

(Effects of the Invention) According to the present invention, since the image capturing section, the image input means, and the illumination means are integrated and installed in one case, the image input device is extremely miniaturized compared to the conventional image input device. can be obtained.

[Brief explanation of drawings]

The first construction drawing is a perspective view showing an embodiment of the image input device according to the present invention, FIG. FIG. 4 is a front view showing another example of the conventional image input device, and FIG. 5 is a front view showing still another example of the conventional image input device. 5... Workpiece, 5a... Imaged surface, 9... Case, 10... Image input means, 15... Image capture means, 17... Illumination means.

Claims (1)

[Scope of Claims] A case having an image capture unit for capturing an image of the imaged surface of the workpiece; an image input means attached to the case for inputting the image of the imaged surface of the workpiece; An image input device comprising: an illumination device installed between an image capture unit and the image input device and illuminating an imaged surface of the workpiece.