JPH01199286A - Relief character reader - Google Patents

Abstract

PURPOSE:To read relief characters in a compact and simple constitution by setting the tip of a light shielding plate at the height approximately equal to the flat surface part of a card and leading the reflected light received from a gap between the recess part of the card and the tip of the light shielding plate into a photodetecting element. CONSTITUTION:In case an LED array 13 illuminates a flat surface part 11 of a plastic card 10, the reflected light sent from the part 11 is cut by the plate 14 and the part 11 and does not inputted to a photodetecting sensor 16 since the tip of the plate 14 is set at the height approximately equal to the part 11. When a recess part 12 is illuminated, a gap is formed between the plate 14 and the card 10. Therefore the light reflected by the part 12 is condensed by a convergency rod lens array 15 and made incident on a photodetecting array 17. Then the characters are read.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a reading device for reading embossed characters formed on a flat surface of plastic, metal, or the like.

[Conventional technology]

FIG. 2 shows the configuration of a conventional reading device disclosed in, for example, Japanese Patent Laid-Open No. 144884/1984. In the figure, reference numeral 1 denotes an object to be read, such as a plastic card, and the object 1 has characters, figures, etc. engraved (embossed) on its flat surface in the form of concave or convex portions. In this embodiment, 3A to 3D, on which letters are engraved (formed as four parts), are lamps that sequentially illuminate the object 1 from four different diagonal directions. A television camera 2 photographs the object 1 illuminated by lamps 3A to 3D.

4 is a binarization circuit, which binarizes the output of the television camera 2. A switch 5 sequentially switches and outputs the output of the binarization circuit 4 when illuminated by the lamps 3A to 3D to the memories 6A to 6D. 7 is or gate,
The outputs of the memories 6A to 6D are output to the memory 8.

When the lamp 3A is illuminated, an image of the characters engraved on the object 1 is photographed by the television camera 2. The signal corresponding to the image at this time is binarized by the binarization circuit 4, input to the memory 6A via the switch 5, and stored. The image stored at this time includes lamp 3A.
Shadows appear in areas where the light cannot reach.

Similarly, the image when illuminated by lamp 3B is memory 6B, the image when illuminated by lamp 3C is memory 6C, and the image when illuminated by lamp 3D is memory 6.
D, respectively. These images are also shadowed by the corresponding lamps.

The outputs of the memories 6A to 6D are added together via the OR gate 7 and input to the memory 8. Therefore, the memory 8 stores an image in which the shadows formed by the respective lamps are combined.

[Problem that the invention seeks to solve]

Since conventional devices require illumination from four directions, a switch 5 and an OR gate 7 are required.
The disadvantage is that the device becomes larger and the cost becomes higher. Furthermore, when the groove width of the engraved character is large, the shadow caused by the illumination does not spread over the entire width of the groove, so that only a binarized image of the peripheral portion of the groove can be obtained. Furthermore, depending on the position of the characters, each lamp may not be illuminated under the same conditions, making it impossible to obtain a correct binarized image.

Therefore, the present invention realizes a device that can read characters correctly regardless of the position of the characters, the width of the groove, etc., with a simple configuration.

[Means for solving problems]

The uneven character reading device of the present invention includes a light source that generates light that irradiates an object to be read that has characters, figures, etc. formed of concave or convex portions formed on a flat surface, and a light source that receives reflected light reflected by the object to be read. and the first part of the flat part, recessed part, or convex part that is close to the light source and the light receiving means, and the flat part Among the parts, recesses, or convex parts, the reflected light in the second part passes through the gap formed between the light source and the second part far from the light receiving means, and the reflected light in the first part passes through the gap. It is characterized by comprising a light shielding means for blocking reflected light.

[Effect]

Light generated by the light source is irradiated onto an object to be read, such as a plastic card, and the reflected light is received by the light receiving means. Characters, figures, symbols, etc. are engraved on the flat surface of the object in the form of concave or convex portions.

A light shielding means so that a gap is not substantially formed between the first part of the object near the light source (the flat part if the part facing the light source is a concave part, and the convex part if the part facing the light source is a convex part). is located. As a result, the reflected light from the part of the cylinder 1 (flat part or convex part) is blocked by the light shielding means and is not input to the light receiving means (or even if it is input, the amount of attenuation is large), and vice versa.
In the second portion (concave portion or flat portion) far from the light source, the reflected light is not blocked by the light shielding means and is input to the light receiving means.

Therefore, the amount of reflected light input to the light receiving means changes depending on whether it is in the first part or in the second part, and by monitoring the output of the light receiving means, it is possible to read characters, figures, etc. from the concave or convex parts. Can be done. The configuration for this purpose is also simple.

〔Example〕

FIG. 1 shows the configuration of a reading device according to the present invention. In the figure, 10 is a plastic card as an object to be read, and characters (including figures, symbols, etc.) are engraved on the flat surface 11 of the card 10 by four parts 12. 13 is an LED array as a light source, which generates light to irradiate the card 10.

Reference numeral 14 denotes a light shielding plate as a light shielding means, which is disposed close to the flat portion 11 of the card 10. 15 is a light shielding plate 14
A focusing rod lens array is placed on the opposite side of the LED array 13 as a light focusing means, and one focal point is near the tip of the light shielding plate 14 and the other focal point is the light receiving element array of the light receiving sensor 16. 17.

The light output from the LED array 13 illuminates the card 10 linearly in a direction perpendicular to the plane of the paper, and the light receiving element array 17 is similarly arranged linearly to receive the reflected light. Although the number of arrays corresponds to the resolution to be achieved, for example, five light receiving elements can be arrayed every 1+ms.

When reading the card 10, the card 10 is moved to the left in the figure (in the direction of arrow A) at a constant speed by a roller or the like (not shown). The light receiving element array 17 is sequentially scanned at regular time intervals in accordance with the moving speed of the card IO.

As shown in FIG. 1(a), when the LED array 13 illuminates the flat part 11 of the card 10, the light shielding plate 14 has its tip at the same height (not in contact with) the flat part 11 of the card 10. ) or at a slightly higher position, so that no gap is substantially formed between the tip and the flat part 11, and the reflected light from the flat part 11 is reflected from the light shielding plate 14 and the flat part 11. A light-receiving sensor 1 serving as a light-receiving means is blocked by a portion 11.
6 is not entered. Or even if it is input, the amount of attenuation is large.

On the other hand, when the recess 12 is illuminated as shown in FIG. 1(b), a gap is formed between the light shielding plate 14 and the card 1o. The tip of the light shielding plate 14 is formed to be sufficiently smaller than the width of the recess 12 (for example, to a width of 0.2 mm). For this reason【! ! The light reflected by the J portion 12 is condensed by the convergent rod lens array 15 and is incident on the light receiving element array 17.

Therefore, the light receiving sensor 16 outputs a signal at a higher level in the part where the recessed part 12 is formed (the embossed part) than in the flat part 11.
Characters can be read by monitoring the output.

FIG. 3 shows the recess 12 formed in the flat part 11 from the back side.
That is, the case where the convex portion 21 is detected is shown. In this case, the tip of the light shielding plate 14 is the same as the convex portion 21 or the tip of the card 10 is
It is placed slightly higher than that so that it can pass with plenty of time.

Therefore, no gap is substantially formed between the light shielding plate 14 and the convex part 21, and the light reflected by the convex part 21 is blocked by the light shielding plate 14 and the convex part 21 and is not input to the light receiving sensor 16 (or is not input to the light receiving sensor 16). (attenuated significantly). - The light reflected by the power factor surface section 11 is input to the light receiving sensor 16 through the gap formed between the light shielding plate 14 and the plane section 11. As a result, the light-receiving sensor 16 outputs a signal at a higher level in the flat portion 11 than in the convex portion 21 (embossed portion), contrary to the case described above.

By moving the card 10 in this manner and sampling the output of the light receiving sensor 16 in synchronization with this movement, the characters on the entire card 10 can be read.

〔Effect of the invention〕

As described above, according to the present invention, the tip of the light-shielding plate is arranged at approximately the same height as the flat part (or convex part) of the card, and the gap between the concave part (or flat part) of the card and the tip of the light-shielding plate is The reflected light is input to the light-receiving element through the gap formed between the two sides, and one reflected light is blocked by not forming a gap between the flat part (or convex part) and the tip, making it compact and simple. And with an inexpensive configuration.

It becomes possible to read characters accurately.

[Brief explanation of the drawing]

- Fig. 1 is a side view showing the configuration of the reading device of the present invention, Fig. 2 is a block diagram showing the configuration of the conventional reading device, and Fig. 3 is a side view showing the configuration of the reading device of the present invention.
The figure is a side view of the reading device of the present invention when reading a card from the back side. 1... Object to be read 2... Television cameras 3A to 3D... Lamp 4... Binarization circuit 5... Switches 6A to 6D... Memory 7... OR gate 8... Memory 10...Plastic card 11...Flat portion 12...Concave portion 13...LED array 14...Light blocking plate 15...Focusing rod lens array 16...Light receiving sensor 17...Light reception Element array 21... Convex portion Patent applicant Oki Electric Industry Co., Ltd.

Claims (1)

[Scope of Claims] A light source that generates light that irradiates an object to be read that has characters, figures, etc. formed with concave or convex portions on a flat surface, and a light receiving means that receives reflected light reflected by the object to be read. and the first part of the flat part, the recessed part or the convex part, which is close to the light source and the light receiving means, and is arranged close to the first part so that no gap is substantially formed between the flat part, the recessed part Alternatively, among the convex parts, a gap formed between the light source and the second part that is far from the light receiving means allows the reflected light at the second part to pass through to the light receiving means, and blocks the reflected light at the first part. What is claimed is: 1. A textured character reading device comprising: a light shielding means.