JPH0757038A - Bar code read system - Google Patents

Abstract

PURPOSE:To efficiently execute a correct read with superior reliability by providing an error detection and correction generation part which detects an error in a data code part and corrects the error. CONSTITUTION:An ECC(error detecting and correcting function) generation part 23 extracts a data code and an ECC code out of an input part 22 and performs predetermined ECC arithmetic corresponding to those codes. The generation part 23 judges the presence of an error unless the data codes and ECC codes before and after the arithmetic match each other as a result of the ECC arithmetic and when the error is caused by only one of them, the code is corrected and outputted to an output part 24; and the opening of a gate is indicated with a control signal C1, but when the error is caused by both the codes, the codes are outputted to the output part 24 in the form before the ECC arithmetic and the closure of the gate is indicated with the signal C1. The output part 24 outputs the code which has not error from the beginning or the code having its error corrected to a read part 25 according to the gate opening/closure indication.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bar code reading system comprising a bar code to be read and a bar code reading device for recognizing information represented by the bar code, and more particularly to error detection and correction ( EC
C) A bar code reading system having a function.

[0002]

2. Description of the Related Art In a bar code reading system, the bar code may be erroneously read or unreadable due to stains, damage or uneven printing. In particular, erroneous reading is a problem because there is a risk that the subsequent processing may be performed based on the information that is erroneously recognized without noticing this.

In response to the above problem, there has been proposed a bar code reading system equipped with means for detecting defects such as dirt on a bar code. For example, in Japanese Unexamined Patent Application Publication No. 1-25108, a bar code is composed of an information bar code string and a reference bar code string, and both bar code strings are read by a bar code reading device to be compared to detect a bar code defect. A barcode reading method for detecting is described.

In Japanese Patent Laid-Open No. 2-259892, a grid code different from a bar code is generated, but a grid code having a parity portion is generated in advance so that a parity check can be performed when reading. A device for doing so is described.

[0005]

However, in the above bar code or other code reading system, although the defective code can be detected by the means for detecting the defective code, the defective code can be corrected. Since it does not have a function to read, it is necessary to read until correct reading is performed, and there is a problem that a relatively long reading time is required.

An object of the present invention is to provide excellent reading reliability,
Moreover, it is to provide a bar code reading system capable of efficiently and correctly reading.

[0007]

According to the present invention, a bar code having a data code part representing information and an error detection and correction code part set corresponding to the data code part, and a bar code of the bar code are provided. A reading device for reading, the reading device calculates an error in the data code part by operating the read data code part and the error detection and correction code part, and corrects the error. A bar code reading system is provided which has a detection and correction generator.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A bar code reading system according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the arrangement of a bar code reading system according to this embodiment.

In FIG. 1, this system has a bar code 10 printed on a label and the like, and a reading device 20. The reading device 20 includes a reading sensor 21 that reads the barcode 10 and outputs an electric signal,
An input unit 22 that temporarily stores a series of electric signals from the reading sensor 21 and sequentially outputs the signals, and an EC that processes the signals from the input unit 22 according to a predetermined procedure.
Based on the calculation results of the C generation unit 23 and the ECC generation unit 23, the signal processed by the ECC generation unit 23, that is, the corrected signal is output to the subsequent circuit, or output when it is uncorrectable. It has an output unit 24 for stopping the reading and a reading unit 25 for performing a normal reading process.

FIG. 2 is a diagram showing the configuration of the bar code 10 shown in FIG. In FIG. 2, a bar code 10 includes a data code section 11 representing information and a data code section 11
And an ECC code section 12 for correcting an error in the data code section 11, and printed on an article package or a sticker label so as to be optically or magnetically readable. Has been done.

FIG. 3 illustrates a bar code 10 having an ECC code section 12. In the example of FIG. 3, the data code part 11 is composed of 32 codes, and the ECC code part 12
Consists of 7 codes.

Next, the bar code reading system will be described in detail according to an operation example.

In FIGS. 1 and 2, the data code portion 11 and the ECC code portion 12 of the bar code 10 are now described.
Is read by the reading sensor 21, and the input unit 2
Stored in 2.

The ECC generation section 23 extracts the data code and the ECC code stored in the input section 22 and performs a predetermined ECC calculation according to these codes.
Since the ECC operation itself is known, it will not be described in detail, but here, description will be given assuming that the operation for correcting only one code error is performed.

The ECC generator 23 outputs the result of the ECC calculation.
If the data code and the ECC code match each other before and after the operation, it is determined that there is no error, the data code and the ECC code are output to the output unit 24, and the control signal C is output.
Instruct to open the gate with ₁ . On the other hand, if they do not match, it is determined that there is an error. If only one of these codes has an error, it is corrected and output to the output unit 24, and at the same time, the gate opening is instructed by the control signal C ₁ , and two or more codes are detected. If there is an error, the data code and the ECC code before the ECC calculation are output to the output section 24 as they are, and the control signal C ₁ instructs the gate to be closed.

The output unit 24 outputs to the reading unit 25 a data code and an ECC code which have no error from the beginning or have no error by correction according to a gate opening / closing instruction (control signal C ₁ ) from the ECC generating unit 23. To do.
On the other hand, if the error is two or more codes, since the gate closing instruction has been received, the data code and ECC code are not output, but there is a reading error, that is, there is a defect such as stain on the bar code. The signal is output to the reading unit 25.

The reading unit 25 recognizes the data code and the ECC code from the output unit 24. However, if there are more than two codes, a read error,
That is, the user is informed by a not-shown notifying means such as a display that the barcode has a defect such as dirt.

As described above, the ECC operation of the bar code reading system according to this embodiment is performed. The barcode having the ECC code shown in FIG.
It can be easily generated using a C code generating device.

As another example of this embodiment, for example,
The ECC code portion 12 of the barcode 10 is a cyclic code,
The ECC generation unit 23 calculates the syndrome,
A configuration example in which an error and an error position are detected and the error is corrected can be considered. Further, depending on the code setting of the ECC code unit 12, it is possible to correct not only one code error but also a plurality of code errors.

[0021]

The bar code reading system according to the present invention has excellent reading reliability and can perform correct reading efficiently.

[Brief description of drawings]

FIG. 1 is a block diagram showing a bar code reading system according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a barcode in the system shown in FIG.

FIG. 3 is a diagram showing an example of data of the barcode shown in FIG.

[Explanation of symbols]

 10 bar code 11 data code part 12 ECC code part 20 reading device 21 reading sensor 22 input part 23 ECC generating part 24 output part 25 reading part

Claims (3)

[Claims] 1. A bar code having a data code section representing information, an error detection and correction code section set corresponding to the data code section, and a reading device for reading the bar code, The reading device has an error detection and correction generation unit for calculating the read data code unit and the error detection and correction code unit to detect an error in the data code unit and correcting the error. Bar code reading system. 2. The bar code reading system according to claim 1, wherein the error detecting and correcting code part of the bar code is a cyclic code. 3. A barcode label obtained by printing the barcode of the barcode reading system according to claim 1 or 2 on a label sheet.