JPH0221027B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to equipment for manufacturing keyboards used as input devices for various electronic devices, and particularly to a device for inspecting characters displayed on key tops.

As shown in the perspective view of FIG. 2, the keyboard consists of a printed circuit board 1, a push button switch 2, a connector 3, and a key top 4 that fits onto the head of the push button switch 2. Although not shown, the key top 4 has a purpose for the keyboard. Various characters and symbols are displayed according to the keyboard, and the arrangement, size, font, line thickness, etc. of the characters and symbols differ depending on the keyboard model.

Keyboards serve as input devices for various electronic devices and are visible to an unspecified number of people, including operators, and they not only have different arrangements of characters and symbols, but also have different sizes, fonts, line thicknesses, etc. Contamination with key tops is absolutely not allowed.

However, as mentioned above, the arrangement, size, font, line thickness, etc. of characters and symbols differ between keyboard models, so when manufacturing keyboards, there are differences in the arrangement of characters and symbols, the size of characters and symbols, etc. Problems often occur due to the mixing of keytops with different fonts, line thicknesses, etc. In order to eliminate such obstacles, we inspect the arrangement, size, font, line thickness, etc. of characters and symbols for each keyboard, but since there are many inspection items and objects, it takes time and is difficult to see with the naked eye. , there is a high possibility that failures will be overlooked.

Therefore, it is desired to provide a pattern identification device that can improve inspection accuracy and shorten inspection time.

(b) Prior Art FIG. 3 is a block diagram showing a conventional pattern identification device.

An imaging optical system 5, a licensor 6 that converts optical signals into electrical signals, an A/D conversion circuit 7, a frame memory 8 that stores images converted into digital signals, a dictionary memory 9 that stores standard patterns, and a frame memory 8. An image memory 10 that cuts out and stores only the inspection target part from the image stored in the image memory 10, a pattern matching circuit 11 that matches the contents of the dictionary memory 9 and the contents of the image memory 10 in detail, and a judgment that determines whether there is a match or a mismatch. It consists of a circuit 12, an output device 13, and a stage 15 that moves a mounted keyboard 14 in the XY direction.

(c) Problems to be Solved by the Invention As a method for inspecting a keytop having a plurality of characters (six in the figure) as shown in FIG. There are two methods: one is to simultaneously check the pattern consisting of ``characters'' against the dictionary, and the other is to check the pattern character by character against the dictionary.

The method of simultaneously checking a pattern consisting of multiple characters against a dictionary is effective in shortening the inspection time, but the ratio of information regarding differences to the information of the entire image becomes small. There are problems such as overlooking the part and misidentifying it as 8.

On the other hand, the method of comparing each character with a dictionary increases the ratio of information about differences to the information of the entire image, improving identification accuracy, but as shown in Figure 4, even if only one character differs, The characters may be different, so it is necessary to match all characters. Therefore, there is a problem that the time required for the inspection increases.

(d) Means for solving the problem A method for identifying patterns of multiple key tops in which only specific parts of multiple characters and symbols have different display patterns, and a standard that handles all patterns at once. At the same time, the above-mentioned problem is solved by comparing and identifying the pattern, and at the same time comparing and identifying the pattern of the specific part with the corresponding standard pattern, and combining the judgment results of both to identify the entire pattern. .

(e) Function For example, when inspecting a keytop that consists of multiple characters and only the last number changes individually, as shown in Figure 4, the pattern of all the characters can be matched at once using a wide-area pattern matching system. At the same time, a local pattern matching system performs identification by matching the pattern in a specific part (the numerical part in the figure), and by integrating the judgment results of both to identify the pattern, the following effects can be achieved. is obtained.

That is, if even one character differs from the determination result of the wide-area pattern matching system, the difference in patterns can be identified by one matching. In addition, even if it is difficult to identify differences based on the judgment results of the wide-area pattern matching system, as in cases 3 and 8, they are simultaneously identified by the local pattern matching system, and the differences in patterns can be identified with a single match. This makes it possible to shorten inspection time.

Further, the problem of overlooking the opening 3 and misidentifying it as 8 is eliminated, and the identification accuracy is improved.

(f) Examples Examples of the present invention will be described below with reference to the attached drawings.
FIG. 1 is a block diagram showing one embodiment of a device for realizing the pattern identification method according to the present invention, FIG. 5 is a block diagram showing another embodiment of the present invention, and FIG. 6 is a block diagram showing still another embodiment of the present invention. , the same objects as in FIG. 3 are represented by the same symbols.

As shown in FIG. 1, an apparatus for implementing the pattern identification method of the present invention cuts out and stores a portion to be inspected from an image stored in a wide-area dictionary memory 16 and a frame memory 8 that store wide-area standard patterns. Wide area image memory 17, wide area dictionary memory 1
6 and the contents of the wide area image memory 17 in detail, a wide area pattern matching system consisting of a wide area pattern matching circuit 18, a local dictionary memory 19 storing local standard patterns, and a frame memory 8. a local image memory 20 that cuts out and stores a portion to be inspected from an image; a local pattern matching circuit 21 that matches the contents of the local dictionary memory 19 with the contents of the local image memory 20 in detail;
A local pattern matching system consisting of the matching results of the wide area pattern matching circuit 18 and the local pattern matching circuit 2
It is provided with an OR circuit 22 that performs a logical OR of the comparison results of 1.

When inspecting a keytop having a plurality of characters as shown in FIG.
6. The wide-area image memory 17 and the wide-area pattern matching circuit 18 collectively match a pattern consisting of a plurality of characters with a dictionary, and at the same time, the local dictionary memory 19, the local image memory 20, and the local pattern matching circuit 21 , the different characters (in the figure, only numbers) are checked against the dictionary one by one.

In other words, by performing the conventional method of checking a pattern consisting of multiple characters against a dictionary all at once and the method of checking each character against a dictionary in parallel, it is possible to improve inspection accuracy and shorten inspection time. It is possible to provide a pattern identification device that combines the features of both methods.

Further, in another embodiment shown in FIG. 5, instead of the local pattern matching circuit 21 of the previous embodiment, the contents of the local dictionary memory 19 and the contents of the local image memory 20 are compared in detail, and the pattern in a specific portion is checked. It is equipped with a feature extraction circuit 23 that extracts features such as area, perimeter, and projected width.

Therefore, by combining the output signals of the wide-area pattern matching system and the output signals of the feature extraction circuit 23 and making a determination, a pattern identification method that can improve inspection accuracy and shorten inspection time in the same manner as in the above embodiments is provided. It is possible to provide a device that realizes this.

According to this embodiment, differences in line thickness can be identified as differences in pattern area, so differences in line width between characters and symbols of the same pattern, etc., which were difficult to identify with conventional pattern recognition devices, can be identified as differences in pattern area. identification becomes possible.

Furthermore, it is also possible to use the methods shown in the above two embodiments in combination. Another embodiment shown in FIG. 6 includes a local pattern matching circuit 21 and a feature extraction circuit 2.
To provide an apparatus which realizes a pattern identification method which is equipped with the following features and which enables improvement of inspection accuracy and shortening of inspection time as in the above two embodiments, and also enables identification of differences in line width, etc. Can be done.

(g) Effects of the Invention As described above, according to the present invention, it is possible to provide an apparatus that implements a pattern identification method that improves inspection accuracy and reduces inspection time.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a device implementing the pattern identification method according to the present invention, FIG. 2 is a perspective view showing the external appearance of a keyboard, and FIG. 3 is a block diagram showing a conventional pattern identification device. Figure 4 shows an example of character display on the key top.
FIG. 5 is a block diagram showing another embodiment of the apparatus for realizing the pattern identification method according to the invention, and FIG. 6 is a block diagram showing still another embodiment of the apparatus for realizing the pattern identification method according to the invention. , is. In the figure, 16 is a wide area pattern dictionary memory;
17 is a wide area image memory, 18 is a wide area pattern matching circuit, 19 is a local pattern dictionary memory, 20 is a local image memory, 21 is a local pattern matching circuit, 2
2 represents an OR circuit, and 23 represents a feature extraction circuit.

Claims (1)

[Scope of Claims] 1. A pattern identification method for a plurality of keytops in which only specific portions of a plurality of characters and symbols have different display patterns, the method comprising: comparing all the patterns at once with a corresponding standard pattern; At the same time, the pattern of the specific part is identified by comparing it with the corresponding standard pattern,
A pattern identification method characterized by integrating both determination results to identify all patterns.