JP2006134160A - Optical information reading device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical information reading device capable of easily and surely reading a multi-stage code showing one set of information. <P>SOLUTION: When reading the multi-stage code C by a code scanner 1, its reading is performed at a multi-stage code reading mode, while a group of codes is positioned within a reading field F. Then, a control unit of the code scanner 1 reads a code for each stage which forms the multi-stage code C and determines whether these codes have a common feature. When the codes have a common feature, the control unit determines that it is a multi-stage code showing one set of information and restores original information from the information read from each code. Accordingly, codes without common features are decided as being a group of codes which do not form the multi-stage codes, and a group of codes that only form the multi-stage codes are read surely and easily, because reading is not performed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical information reader capable of reading a multistage code including a plurality of one-dimensional codes and two-dimensional codes indicating a set of information.

Since a single one-dimensional code or two-dimensional code limits the amount of information that can be read, in order to increase the amount of information, a plurality of one-dimensional codes or two-dimensional codes indicating one set of information are arranged. A code scanner capable of reading a multistage code is provided (see Patent Document 1).
Japanese Patent Laid-Open No. 11-3398

  In such multi-level code reading, it is usually necessary for the operator to specify the reading based on the multi-level code data and code type from the host, and reading is required, which causes extra work for the operator. This is inconvenient.

  Even when the above method is used, it is determined whether the data or code type is simply the same or not because it is a multi-stage code. The multi-stage code and the second multi-stage code may be mistakenly combined. For this reason, an incorrect combination of code groups is erroneously determined as a multi-stage code, which is an obstacle to work.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide an optical information reader capable of easily and reliably reading a multistage code indicating a set of information.

  According to the first aspect of the invention, when the common feature of the multi-stage code to be read is set by the feature setting means and the reading process is executed in a state where the multi-stage code is positioned in the reading field, the feature detecting means A code having a common feature set by the feature setting unit is detected in the multistage code located in the two-dimensional image captured by the sensor. Since the reading unit reads the code group as a multi-stage code indicating one set of information only when the code group to be read has a set common feature, the multi-stage code indicating one set of information can be easily obtained. In addition, the reading process can be performed reliably.

According to the invention of claim 2, since one feature can be set as a common feature, a plurality of features can be set in combination, so that a common feature can be arbitrarily set. .
According to the invention of claim 3, since the number of code stages constituting the multi-stage code can be set in addition to the common feature, the reliability of the multi-stage code reading process can be further enhanced.

According to the invention of claim 4, since the common feature can be set by a logical expression, combinations of common features can be diversified.
According to the invention of claim 5, since a logical expression that excludes any common feature can be created as a common feature, combinations of common features can be further diversified.
According to the invention of claim 6, various multi-stage codes can be read and processed.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, FIG. 2 schematically shows an internal configuration of a code scanner 1 as an optical information reading apparatus. This code scanner 1 is called a handy terminal that is operated by an operator by hand, and is a one-dimensional code such as a bar code, a two-dimensional code such as a QR code (registered trademark), or a character for OCR reading. It is possible to read various codes such as. In addition to reading the code, it also has functions of processing (decoding processing) and storing the read code data, data communication with the management computer, and the like.

  The code scanner 1 incorporates a reading mechanism 3 for optically reading a code, a control device (corresponding to reading means, feature setting means, and feature detection means) 4 (see FIG. 1), etc., in a case 2. Consists of. Further, as shown in FIG. 2, the case 2 is bent so that the base end side is a grip portion, the front end side is slightly inclined downward, and a reading window portion 2a is provided at the front end portion.

  A key input unit 5 including a plurality of key switches 5a is provided on the upper surface of the case 2 so that a program to be installed can be selected and a type of code to be read can be specified by an operator's operation. It has become. Further, a trigger switch 6 (see FIG. 3) for reading is provided on both side portions of the case 2, and a display unit 7 made of, for example, an LCD is provided on the upper surface of the case 2. Note that the key switch 5 a, the display unit 7, the control device 4, and the like are mounted on a printed circuit board 8 disposed in the case 2. Further, in the case 2, a secondary battery (not shown) serving as a power source is incorporated.

  On the other hand, the reading mechanism 3 includes an area sensor 9 composed of a CCD two-dimensional image pickup device provided at the center of the inner portion of the reading window 2a, an image pickup lens 10 provided in front of the area sensor 9, and the image pickup lens 10. A plurality of illumination LEDs 11 (see FIG. 1) that are provided in the vicinity (upper side) of the LED and serve as illumination light sources for code reading, an illumination lens (not shown) positioned in front of these illumination LEDs 11 and the like. It is prepared for. The area sensor 9 includes, for example, 600 horizontal pixels and 400 vertical pixels, and has a two-dimensional reading visual field F as shown in FIG. The illumination LED 11 and the illumination lens illuminate the entire reading field F evenly.

  With such a configuration, the operator brings the reading window portion 2a of the code scanner 1 close to the reading object (for example, the label L shown in FIG. 3) on which the code (for example, the barcode C shown in FIG. 3) is recorded. When the reading operation, that is, the trigger switch 6 is turned on (for example, the optimum reading distance is 90 mm), the reading target is illuminated by the illumination LED 11, and the reflected light is imaged by the area sensor 9 to read the code. It is done. Although not shown, the code may be a two-dimensional code such as a QR code or a character for OCR reading, and various codes such as slips and catalogs can be read. It is.

  The reading mechanism 3 is provided with a marker LED 13 (see FIG. 1) for indicating a reading range with respect to a reading target and a light projecting lens (not shown) arranged in front thereof. The marker LED and the light projecting lens are provided in the vicinity of the periphery of the imaging lens 10, and as shown in FIG. 3, the marker light M composed of slit light respectively so as to indicate the reading range and the reading center. It comes to irradiate.

  The image captured by the area sensor 9 is output to the control device 4. Based on the image captured by the area sensor 9 in the lighting state of the marker LED 13, the control device 4 displays the field of view of the area sensor 9. The irradiation position of the marker light in the whole can be recognized.

  FIG. 1 is a functional block diagram schematically showing the electrical configuration of the code scanner 1. In FIG. 1, a control device 4 is mainly composed of a microcomputer, and performs decoding processing of signals from the reading mechanism 3, control of the entire device, and the like. That is, the control device 4 controls the display of the display unit 7 according to the input of the operation signal from the key input unit 5 or the trigger switch 6, controls the lighting of the illumination LED 11, and as described above, The LED 13 is controlled.

  The control device 4 is input with the code image data read by the area sensor 9 and decoded. At this time, although not shown, an amplifier for amplifying the imaging signal of the area sensor 9, a binarization circuit for converting the binarized data, and the like are provided. An image memory 15 is provided connected to the control device 4 and the area sensor 9. Furthermore, the control device 4 is connected, for example, with a sound generating unit 16 that emits a buzzer sound when a code is read, and a data communication unit that performs data communication with an external device (for example, a management computer) using, for example, infrared rays. 17 is connected.

Here, in addition to the basic reading mode of reading one code positioned in the reading visual field F, the control device 4 performs a multi-level code reading mode for reading a multi-level code indicating a set of information positioned in the reading visual field F. I have. In this case, since the multistage code needs to be composed of a code group indicating one set of information, in this embodiment, a plurality of codes satisfy a preset common feature combination as described later. Only in such a case, the reading process is executed by recognizing as a code group constituting a multi-stage code indicating one set of information.
Note that the multistage code includes not only a code arranged in the vertical direction but also a code arranged in the horizontal direction.

  FIG. 4 shows an example in which common features of multi-stage codes that can be read by the code scanner 1 of this embodiment can be combined. In FIG. 4, the common feature is set by the logical product of any one of the conditions 1 or the condition 1 and the condition 2 that can be combined. The conditions 1 and 2 include “code type”, “ Code position, module size, code size, code data type, code data, margin size, and error correction level are set. Such setting is performed by setting the code scanner 1 to the multi-stage mode reading mode and displaying a setting screen on the display unit 7 of the code scanner 1 and setting an arbitrary combination on the setting screen.

  “Code type” means JAN (EAN) -8/3, CODE39, ITF (Interleaved 2 of 5), NW-7 (CODEABAR), etc. in the case of a one-dimensional code, QR code, PDF417, Data Matrix, Maxi Code, etc. The “code position” is the start position of the code. In addition to the left alignment shown in FIG. 5A and the center alignment shown in FIG. 5B, reading is OK in the case of right alignment, as shown in FIG. If the positions are not aligned as in the example, reading is NG. The bar code shown in the drawing is different from the actual bar code, and so on.

  The “module size” is the size of one module constituting the barcode. When the module size is the same as in the example shown in FIG. 6A, reading is OK, and the module as in the example shown in FIG. When the sizes are different, the reading is NG. “Code size” means that the barcode size is the same. If the code size is the same as in the example shown in FIG. 7A, reading is OK, and the code size is the same as in the example shown in FIG. If they are different, it is read NG. “Code data type” means that the data format of the bar code is the same, and if both codes are upper case data as shown in FIG. 8A, the reading is OK, and the example shown in FIG. If each code is different in numerals / uppercase letters as shown in FIG.

  “Code data” is data indicated by a barcode or QR code. For example, when “first character other than“ 2 ”” is set as shown in FIG. The barcode of the eye is read OK. “Margin size” means that the margin size of each bar code is the same. When the margin size is the same as in the example shown in FIG. 10A, reading is OK, as in the example shown in FIG. If the margin sizes are different, the reading is NG. The “error correction level” is a level for reading even if it is dirty or partially missing. For example, in the case of a QR code, 7%, 15%, 25%, and 30% are missing. Also, a readable error correction level can be set.

  In the example shown in FIG. 4, “code type” can be combined with “code position”, “code data type”, “code data”, and “margin size”, and only when “code type” is the same, “module size” ”And“ code size ”can be combined, and“ error correction level ”can be combined only in the case of codes having the same“ code type ”and having an error correction function.

If the multi-level code is composed of multiple two-dimensional barcodes, combinations of the same module size and the same code position, or the same error correction level and the same code position are possible. Thus, as in the example shown in FIG. 11, reading is OK when the module size is the same and the codes are aligned in the horizontal direction, and reading NG is performed when the modules are aligned in the vertical direction but the module sizes are different.
If the multistage code is composed of a one-dimensional code and a two-dimensional code, reading is OK when the centers of the codes are aligned as in the example shown in FIG.

  Furthermore, combinations of conditions for designating common features can be expressed by conditional expressions. In the case of condition 1 and condition 2, they can be expressed by “condition 1” AND “condition 2”. In this case, not only the logical product of condition 1 and condition 2 (logical expression AND), but also the logical sum of condition 1 and condition 2 (logical expression "condition 1" OR "condition 2") The condition may be set by negation (NOT in the logical expression).

Next, the operation of the above configuration will be described.
When reading a multistage code, the code scanner 1 is set to a multistage code reading mode, and at least one common feature shown in FIG. 4 is designated, and then the reading field F indicated by the marker LED 13 as shown in FIG. The reading operation is performed with the multi-stage code to be read positioned in the position. As a result, the code scanner 1 executes a multi-stage code reading mode.

  FIG. 13 is a flowchart illustrating the operation of the control device 4 of the code scanner 1 in the multistage code reading mode. In FIG. 13, the control device 4 reads the first code among the codes to be read located in the reading visual field F (S101), determines whether all the codes have been read (S102), If not finished (S102: NO), the next code is read in order (S101). When the code reading process for all the stages is completed (S102: YES), a feature check process is executed (S103).

  FIG. 14 shows a feature check process of the code scanner 1. In FIG. 14, the control device 4 determines whether the code type, code position, module size, code size, code data type, code data, margin size, and error correction level are designated as common features (S201 to S201). S208) If the specified conditions are not satisfied (S209 to S216: NO), an error occurs (S217).

  On the other hand, if the designated condition is satisfied (S209 to S216: YES), that is, if the code group located in the reading field F has the common feature designated, FIG. In the flowchart shown, it is determined whether a conditional expression including a logical expression indicating a combination of these common features is satisfied (S104). That is, it is determined whether any one of the conditions 1 shown in FIG. 4 or a combination of the conditions 1 and 2 is satisfied.

  When the conditional expression is satisfied based on the determination criteria as described with reference to FIGS. 5 to 12 (S104: YES), the multi-stage code reading process is executed (S105). That is, a set of information consisting of a multi-stage code is read by sequentially reading the codes constituting the multi-stage code and combining the information. Therefore, as shown in FIG. 15, when a plurality of barcodes printed on different forms are to be read in the multi-stage code reading mode by overlapping the forms on which the multi-stage codes are printed, the code to be read is the designated common code. Since the error is notified by not having the above feature, it is possible to prevent such a plurality of codes from being erroneously read as a multistage code.

According to such an embodiment, when multi-stage code reading processing is performed, it is determined whether a code group consisting of a plurality of codes has a pre-specified common feature, and multi-stage code reading processing is performed only when it is established. Therefore, it is possible to prevent a code group not showing one set of information from being read as a multistage code. Therefore, unlike the conventional example in which it is determined whether the data or code type is simply the same or not, it is possible to reliably prevent the reading process from being performed in the case of codes such as overlapping forms. .
In addition, since the combination of common features is expressed by a conditional expression including a logical expression, a complicated combination can be easily set.

(Other examples)
The present invention is not limited to the above embodiment, but can be modified or expanded as follows.
The number of stages of the multistage code may be set in advance. In this case, in addition to the common feature, it can be determined whether the multi-stage code indicates one set of information even with the number of stages, so that erroneous combinations can be prevented more reliably.

  For example, the optical information reader according to the present invention is not limited to a so-called handy terminal, but is a handy type connected to a host computer, that is, a type in which only data is read and data processing is performed on the host computer side. For example, the present invention may be applied to a QR code reading-only device.

The block diagram which shows the electric constitution of the code scanner in one Example of this invention. Code scanner vertical section Front view of label showing field of view by code scanner Diagram showing how each feature is combined The figure which shows the reading result by position check Figure showing the result of module size check Diagram showing the result of code size check The figure which shows the reading result by code data type check The figure which shows the reading result by code data check The figure which shows the reading result by margin size check Diagram showing the reading result of two-dimensional code Diagram showing reading results of 1D code and 2D code Flowchart showing operation of multi-stage code reading mode by control device of code scanner Flowchart showing feature check processing by control device of code scanner A diagram showing the results of reading overlaid forms

Explanation of symbols

In the drawing, 1 is a code scanner (optical information reading device), 4 is a control device (reading means, feature setting means, feature detection means), and 9 is an area sensor.

Claims (6)

Optical information including an area sensor that captures a two-dimensional reading field as a two-dimensional image, and a reading unit that executes a reading process for reading a multistage code positioned in the two-dimensional image by the area sensor as a set of information. In the reading device,
Feature setting means for setting common features of multi-stage codes to be read; and
Feature detection means for detecting a code having a common feature set by the feature setting means among a plurality of codes in the two-dimensional image by the area sensor,
When the feature detecting unit detects a plurality of codes, the reading unit recognizes these codes as a code group constituting a set of multistage codes, and executes a reading process. Reader.   The feature setting means sets a common feature by combining one or more of a code type, a code position, a module size, a code size, a code data type, code data, a margin size, and an error correction level. The optical information reader according to claim 1, wherein The feature setting means sets the number of code stages constituting the multi-stage code in association with a common characteristic of each multi-stage code,
When the number of code stages detected by the feature detection unit matches the number of code stages detected by the feature setting unit, the reading unit recognizes the code group as a set of multi-stage codes and performs a reading process. The optical information reader according to claim 1 or 2, wherein   4. The optical system according to claim 1, wherein when a plurality of types of common features are set in a set of multistage codes, the feature setting means sets the features by a logical expression. Information reader.   5. The optical information reader according to claim 4, wherein the feature setting means can set a negative expression indicating that there is no arbitrary common characteristic among the common characteristics as a logical expression. The optical system according to any one of claims 1 to 5, wherein the multistage code is configured by only one-dimensional code, only two-dimensional code, or a combination of one-dimensional code and two-dimensional code. Information reader.

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