From traditional barcodes to RFID
Introduction: In order to improve the efficiency of computer recognition, enhance its flexibility and accuracy, and get people out of the complex statistical identification work, traditional bar code, two-dimensional bar code, wireless radio frequency identification technology has come out. Although they have their merits, no matter which technology is used to obtain various kinds of information in a timely manner and perform fast and accurate processing.
Overview of Traditional Two-dimensional Bar Codes and Radio Frequency Identification Technology
In order to improve the efficiency of computer recognition, enhance its flexibility and accuracy, and get people out of the complex statistical identification work, traditional bar codes, two-dimensional bar codes, and radio frequency identification technologies have come out one after another. Although they have their merits, no matter which technology is used to obtain various kinds of information in a timely manner and perform fast and accurate processing.
Traditional bar code (also known as one-dimensional bar code) technology is relatively mature. It is widely seen in social life and has been widely used in the world. As a computer data acquisition method, it quickly enters various fields such as commodity circulation, automatic control, and file management with many advantages such as rapidity, accuracy, and low cost. It is also the most commonly used bar code in China. However, since the conventional bar code is one-dimensional, it does not have any information in the vertical direction, the information density is low, and the Chinese characters cannot be displayed, and is easily rejected due to wear or wrinkle, which greatly limits the conventional bar code. The scope of application.
1. Narrow one-dimensional space
The traditional bar code consists of a set of bars and blank symbols arranged according to a certain coding rule and represents a certain character, number, and symbol information. The bar code system is an automatic identification system composed of bar code symbol design, barcode production and scanning and reading. It is the most widely used automatic identification technology.
So far, there are about twenty kinds of common barcodes, of which the widely used code system includes EAN code, Code39 code, cross code 25, UPC code, 128 code, Code93 code, and CODABAR code. Different code systems have different characteristics and are suitable for specific application areas. Here are some typical code systems:
1) UPC code (unified product barcode)
The UPC code was promoted by the U.S. supermarket union in 1973 and is the world's first commercially available bar code system, mainly used in the United States and Canada. UPC codes include UPC-A and UPC-E systems. UPC only provides digital coding, limits the number of digits (12-bit and 7-bit), requires a check code, and allows two-way scanning, mainly used in supermarkets and department stores.
2) EAN code (Europe product barcode)
In 1977, 12 industrial countries in Europe signed a draft contract in Belgium, established the International Bar Code Association, and made reference to the UPC code to develop compatible EAN codes. The EAN code is only a digital number, usually 13 bits, allowing two-way scanning, shortening the code to 8-bit code, and is also mainly used in supermarkets and department stores.
3) ITF25 code (crossing 25 yards)
The bar code length of the ITF25 code is not limited, but its digital data must be even-numbered, allowing bidirectional scanning. The ITF25 code is widely used in logistics management. It is mainly used for the ticket numbering of packaging, transportation and international aviation systems, automobile industry and retail industry.
4) Code39 code
Among 9 code elements of Code39 code, there must be 3 code elements which are thick lines, so Code 39 code is also called "39 code". In addition to the digits 0-9, the Code 39 code also provides English letters A-Z and special symbols. It allows two-way scanning, supporting 44 groups of barcodes, mainly used in industrial products, commercial information, libraries and other places.