JPH0526580Y2 - - Google Patents

Description

[Detailed description of the invention] A. Industrial application field The present invention relates to a pseudo-transmitted light illumination device, in particular,
This is useful when inspecting an object by image processing.

B. Summary of the invention The lighting device according to the invention includes a base plate of a color other than black,
Fluorescent lamps with hoods are placed on both sides of the base plate and emit light from the sides approximately parallel to the base plate, and objects are supported above the hoods of the fluorescent lamps placed on the base plate. By equipping the base plate with a support device that provides a bright background that does not cast shadows between the object and the support device and that does not affect letters, etc., the object can be suspended in the air without being exposed to light from the front, and as a silhouette. It was designed to raise the level.

C. Prior art When inspecting objects such as wire harnesses using image processing, it is known that lighting has a significant effect on the inspection results, so lighting is performed so that only the object to be inspected stands out from the background. There is a need.

A common method of illumination for this purpose is to shine transmitted light onto the object.
Photographed as a silhouette using a camera.

However, depending on external conditions, etc., a configuration using transmitted light may not be possible. In such a case, there is no other choice, so place the object 2 on the white board 1 as shown in Figure 3, place the lighting lamp 3 in front of the TV camera 4, and verify the object 2 from the front. A method is being taken. The TV camera 4 photographs the object 2 brightly, not its silhouette. 5 is a lens, and 6 is an image processing device.

Problems to be solved by the invention In the conventional technology shown in Fig. 3, since it is illuminated from the front, an unnecessary shadow of the object 2 is generated on the white board 1, and there are also patterns and letters on the white board 1. Since these do not disappear, it is not possible to make only the object 2 stand out.

In view of the above-mentioned conventional technology, the present invention aims to provide a so-called pseudo-transmitted-light type illumination device that can highlight an object to the same extent as transmitted light without using transmitted light. .

E Means for Solving the Problems The lighting device according to the present invention has a base plate other than black,
Fluorescent lamps with hoods are placed on both sides of the base plate and emit light from the sides approximately parallel to the base plate, and objects are supported above the hoods of the fluorescent lamps placed on the base plate. The present invention is characterized in that it includes a support tool for providing support.

F Effect In the above configuration, the object is separated from the base plate and supported in a suspended state. Since the fluorescent lamp illuminates the base plate approximately parallel to the base plate from both sides, the base plate will have a uniform bright background shadow without being affected by the characters on the base plate. Furthermore, the shadow of the support is eliminated by illumination from both sides. Furthermore, since the object is located above the hood, the object is not illuminated from the front and its shadow disappears from the base plate. Furthermore,
The hood blocks fluorescent light from directly entering the camera.

As a result, when an object is viewed from the front with a camera, only the silhouette of the object appears to stand out against the backdrop of the uniformly bright base plate, achieving illumination equivalent to illumination by transmitted light.

G Example An embodiment of the present invention will be described based on the drawings.

In FIGS. 1 and 2, hooded rod-shaped fluorescent lamps 7, 7 are placed on both sides of the white board 1, respectively. The fluorescent lamp 7 is placed as close as possible to the upper surface of the white board 1 so that the light from the fluorescent lamp 7 hits the white board 1 from the side approximately parallel to the white board 1. A hood 8 is attached to the fluorescent lamp 7 so that the light from the fluorescent lamp 7 does not directly enter the TV camera 4. A rod-shaped support 9 having a U-shaped tip is installed on the white board 1. In this embodiment, in order to inspect a branched object 10 such as a car wire harness by image processing, a large number of supports 9 are used and each part of the object 10 is placed on each U-shaped portion. An object 10 is supported so as to float above a white board 1 at a higher position than a hood 8. The upper part of the hood 8 is parallel to the white board 1, and its extension line reaches the bottom of the U-shaped part of the support 9.

For image processing, a TV camera 4 is placed above the white board 1 to photograph the object 10 from the front and provide a signal to the image processing device 6. A monitor 11 is connected to the image processing device 6 so that an operator can visually view the photographed images, and a host computer 12 is connected to output the image processing results. In addition, in order to reduce the flicker of the fluorescent lamp 7,
The power source 13 is a high frequency power source.

In the above-mentioned embodiment, since the light hits the white board 1 from both sides in an extremely nearly parallel manner, the white board 1
Even if there are letters, patterns, etc. on it, the white board 1 is uniformly and brightly illuminated without being affected by them. Further, the shadows of the support 9 and the object 10 also disappear from the white board 1. Furthermore, the object 10 is not illuminated from the front. Therefore, the white board 1 forms a bright background against the object 10, exhibiting an effect similar to that of transmitted light, and the TV camera 4 photographs only the object 10, standing out as a silhouette in the bright background.

Any image processing method may be used. For example, an example will be described in which the presence or absence of harness parts such as tubes, clampers, grommets, protectors, and taping is inspected on an inspection line after manufacturing wire harnesses. First, an image of a non-defective product is input from the TV camera 4, binarized into black and white, the number of black pixels is counted, and the result is stored as the area of the non-defective product. Next, an image of the object to be inspected is input from the TV camera 4, similarly binarized, the number of black pixels is counted, and the difference from that of a non-defective item is calculated. If the difference is outside the variation range for non-defective products, the product is determined to be defective.

Note that any base plate other than black, such as yellow or gray, can be used in place of the white plate 1, but it is preferable to use a base plate with a color as close to white as possible so that it can be easily distinguished from the silhouette of the object 10. It is preferable to use

Further, in the inspection line, the positions of the TV camera 4 and the fluorescent lamp 7 are generally fixed, and the white board 1 is configured to be moved between the fluorescent lamps 7 and 7 by a conveying device below the TV camera 4. However, it is also possible to fix the fluorescent lamp 7 to the white board 1.

H. Effects of the invention According to the invention, by illuminating the base plate distant from the object substantially in parallel from both sides, it is possible to realize illumination similar to that achieved by transmitted light.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram showing one embodiment of the present invention;
The figure is a perspective view thereof, and FIG. 3 is a configuration diagram of a conventional example. In the drawings, 1 is a white board, 4 is a TV camera, 6 is an image processing device, 7 is a fluorescent lamp, 8 is a hood, 9 is a support, and 10 is an object.

Claims (1)

[Scope of utility model registration request] A non-black baseplate, hooded fluorescent lamps placed on both sides of the baseplate that emit light from the sides approximately parallel to the baseplate, and above the hood of the fluorescent lamp placed on the baseplate. What is claimed is: 1. A pseudo-transmitted light type illumination device, comprising: a support for supporting an object at a position of .