What are the main features of multifunctional hidden bar code system?

One-dimensional barcode (1D barcode) One-dimensional barcode only indicates information in one direction (generally horizontal direction), and does not indicate any information in the vertical direction. Its height is usually for the convenience of readers' alignment. The application of one-dimensional bar code can improve the speed of information input and reduce the error rate, but there are some shortcomings in one-dimensional bar code: the capacity of L data is small: about 30 characters L can only contain letters and numbers; L Bar code size is relatively large (low space utilization); L After the bar code is damaged, it is impossible to read the bar code of 2D bar code that stores information in two-dimensional space in horizontal and vertical directions. It is called a two-dimensional bar code. The classification of two-dimensional bar codes is the same as that of one-dimensional bar codes, and there are many different coding methods, or coding systems. As far as the coding principles of these codes are concerned, they can usually be divided into the following three types: 1. Linear stacked QR code is formed by vertically stacking multiple one-dimensional codes on the basis of one-dimensional bar code coding principle. Typical coding systems are: Code 16K, Code 49, PDF4 17, etc. 2. Matrix QR code is coded in rectangular space through the different distribution of black and white pixels in the matrix. Typical coding systems include: Aztec, Maxi code, two-dimensional code, data matrix and so on. 3. Postal codes are coded by bars with different lengths, which are mainly used for mail coding, such as Postnet and BPO 4-State. Among many kinds of 2D barcodes, the commonly used coding systems are: DataMatrix, Maxicode, AZTEC, QR Code, Vericode, PDF 4 17, Ultra Code, Code 49, Code 16K, etc. Among them, the L data matrix is mainly used to identify small parts in the electronics industry, such as codes printed on the back of Intel Pentium processors. L Maxi Code was developed by United Parcel Service (UPS) to sort and track parcels. L * Aztec is introduced by Welch Allyn Company of the United States, and it can accommodate up to 3832 numbers or 3067 alphabetic characters or 19 14 bytes of data. Features 1. Large information capacity. For example, the PDF4 17 code can represent not only letters, numbers and ASCII characters, but also binary numbers. 2. Error correction ability One-dimensional barcodes usually have the verification function to prevent misreading. Once the barcodes are defaced, they will be rejected. Two-dimensional bar code can not only prevent errors, but also correct them. Even if the bar code is partially damaged, the correct information can be recovered. 3. Ordinary printing equipment with low printing requirements can print and fax can read. 4.PDF4 17 code can be read by various reading devices, laser readers with grating and image readers with line scanning and area scanning. 5. The size can be adjusted to suit different printing spaces. 6. Coding system has become an international standard. Error correction function The error correction function of two-dimensional bar code is realized by repeating some information (redundancy). For example, in the PDF4 17 code, a line contains not only the information of its own line, but also some information reflecting the characters in other positions (error correction code). In this way, even when a part of the bar code is damaged, its information can be recovered by error correction codes existing in other positions. The error correction capability of PDF4 17 is divided into 0~8***9 levels according to the number of error correction codes, as shown in Figure 4. The higher the level, the more correction codes, the stronger the correction ability and the larger the bar code. When the correction level is 8, even if the barcode is defaced by 50%, it can be read correctly. Advantages of QR code As can be seen from the above introduction, QR code has obvious advantages over one-dimensional bar code, which can be summarized as: 1. The data capacity is larger. 2. It exceeds the limit of alphanumeric characters. 3. The relative size of bar code is small. 4. The application of the QR code with anti-destruction ability is 1. A typical transportation business process usually goes through: supplier-> supplier; Freight forwarder, freight forwarder-> Freight company, freight company-> Several processes, such as customers, involve the processing of delivery documents in each process. Freight documents contain a lot of information, including: shipper information, consignee information, cargo list, mode of transportation and so on. The premise of document processing is data entry. Manual keyboard input method has the problems of low efficiency and high error rate, which can no longer meet the requirements of modern transportation industry. Two-dimensional bar code provides a good solution in this respect. It is fast and accurate to compile the contents of the documents into two-dimensional codes, print them on the delivery note, scan them with two-dimensional code readers in all aspects of the transportation business, and input the information into the computer management system. In the United States, although EDI application has revolutionized the core part of business process, it unfortunately ignores the key role in the process-freight company. Many EDI messages are always late for freight forwarders, which leads to the failure to confirm the accurate freight document information in time, and affects the freight transportation and the generation of customer documents. The American Freight Association (ATA) therefore proposed a paper EDI system. The sender compiles the EDI information into a PDF4 17 barcode label and submits it to the freight forwarder. By scanning the bar code, the information is immediately transmitted to the freight forwarder's computer system. All this happened at the right time and place, which greatly improved the efficiency of the whole transportation process. 2. Application of Identification Card The U.S. Department of Defense printed the code PDF4 17 on the military identification card. The cardholder's name, rank, photo and other personal information are compiled into PDF4 17 code and printed on the card. This card is used to manage access to important places and hospital visits. The advantages of this application are real-time data acquisition, low implementation cost, reading even if the card is damaged (such as shooting), and anti-counterfeiting. The identity card of the Hong Kong Special Administrative Region also adopts the encoding of PDF4 17. Other applications, such as business license, driver's license, passport, temporary residence permit for urban floating population in China, medical insurance card, etc. It is also a good application direction. 3. Application of documents and forms Every broker of Seimei Insurance Company in Japan will take a laptop with him when meeting with customers. Every policy and agreement is made and printed in the computer. When they return to the office, they need to manually input the policy data into the company's mainframe. In order to improve the accuracy and speed of data entry, they compiled the contents of the policy into PDF4 17 barcode when making the policy, and printed it on the document, so that they could scan the barcode with a two-dimensional barcode reader and enter the data into the host. Other similar applications include: customs declaration forms, tax returns, various application forms of government departments and so on. 4. Asset Tracking American Steel Pipe Company has different kinds of pipelines to be maintained in various places. In order to track each pipe, they compiled the information such as the number, location number, manufacturer, length, grade, size and thickness of the pipe into a PDF4 17 barcode, and made a label and stuck it on the pipe. When the pipeline is dismantled or installed, the operator scans the bar code label and the database information is updated in time. Factories can track production equipment with two-dimensional bar codes; Hospitals and clinics can also use two-dimensional bar code tag tracking equipment, computers and surgical instruments. 5. Mixed code and its application With the development of society, the progress of science and technology, the improvement of people's living standards and the intensification of market competition, people's requirements for information are also increasing. One-dimensional bar code is used in some traditional fields, such as commerce, medicine, logistics and transportation. Due to the limitation of information capacity (generally only the identification number of goods or businesses can be identified), it is increasingly unable to meet people's requirements. The continuous progress of two-dimensional bar code technology is causing changes in these application fields. The UCC organization (Unified Coding Committee) of the United States has introduced a new coding system-mixed code, that is, the combination code of one-dimensional code and two-dimensional code. Wherein, the one-dimensional code can be UCC/ean- 128upc/ean reduced space symbol (RSS), The two-dimensional code can be * CC-A (a variant of PDF4 17 microcode dedicated to mixed codes) * CC-B (standard PDF4 17 microcode) * CC-C (standard PDF4 17)* One-dimensional barcode part contains identification number, while two-dimensional barcode part contains supplementary information * It can be PDF4/kloc. One-dimensional bar code represents a limited amount of data and does not have the function of error correction, while two-dimensional bar code makes up for this deficiency. Two-dimensional bar code has just been developed in recent years and is being applied in many fields. One of the small photoetched squares we saw on the Pentium processor shell was the Data Matrix two-dimensional barcode. PDF4 17 2D barcode is a stacked 2D barcode, which is widely used at present. PDF4 17 barcode was invented by YMBOL company in America, and PDF (portable data file) means "portable data file". Each bar code character consists of four bars and four empty *** 17 modules, so it is called PDF4 17 bar code. PDF4 17 barcode can represent numbers, letters or binary data, and can also represent Chinese characters. PDF4 17 barcode can hold at most 1850 characters or 1 108 bytes of binary data. If only numbers are represented, it can hold 27 10 numbers. The error correction capability of PDF4 17 is divided into 9 grades, and the higher the grade, the stronger the error correction capability. Due to this error correction function, the defaced 4 17 barcode can also be read correctly. At present, China has formulated the national standard of PDF4/KOOC-0/7 code (GB/T/KOOC-0/7/KOOC-0/72-/KOOC-0/997). The basic characteristics of PDF4 17 bar code symbol can encode all ASCII characters or 8-bit binary data in the character set, and can represent continuous Chinese character types and multi-line character self-checking function. Symbols are variable in size, ranging in height from 3 to 90 lines. The width of 90 to 583 modules can be read from two directions. The number of error correction codes is 2 to 5 12, and the maximum data capacity (when the error correction level is 0). Each symbol represents 1850 capital letters or 27 10 numbers or 1 108 bytes. Additional attributes can be selected, and the error correction level can be scanned across lines. Macro 4 17 barcode, global tag identifier and other PDF4 17 barcodes have the greatest advantages of huge data capacity and strong error correction ability. QR code QR code (this bar code contains the following blue characters, and the error correction level is M) is a matrix QR code symbol developed by Denso Corporation of Japan in September 1994. It not only has the advantages of large information capacity, high reliability, various text information of Chinese characters and images, strong security and anti-counterfeiting. One-dimensional bar codes and other two-dimensional bar codes. It also has the following main features: code QR code data martix pdf 417 code classification matrix developed by Denso Corporation (Japan) I.D. Matrix (USA), stacking reading speed * 30/ 2~3 PCs/sec, 3 PCs/sec, omni-directional reading direction (360) 10, reading mode and dark. Bar width and size, Chinese characters stand for 13bit 16bit * Each symbol stands for 65438 ultra-high-speed reading: From the English name of QR code, we can see that ultra-high-speed reading is the main feature that distinguishes QR codes from four-one-seven bar codes and data matrices. When reading two-dimensional code with CCD, the information in the whole two-dimensional code symbol is read by hardware through the position detection pattern of the two-dimensional code symbol, so the time required for information reading is very short, which has the characteristics of ultra-high speed reading. Using CCD two-dimensional bar code reading equipment, it can read 30 100 characters of two-dimensional code symbols per second; For 4 17 bar code symbols with the same data information, only 3 symbols can be read per second; For Data Martix matrix codes, only 2 ~ 3 symbols can be read per second. The ultra-high-speed reading of QR code can be widely used in industrial automation production line management and other fields. Omni-directional reading: QR code has the feature of omni-directional reading (360), which is another main feature of QR code over line-type two-dimensional bar code, such as 4 17 bar code. Because the 4 17 bar code is realized by truncating the one-dimensional bar code symbol on the line height, it is difficult to realize all-round reading. Its reading orientation is only 10, which can effectively represent China Chinese characters and Japanese Chinese characters. Because the two-dimensional code uses a specific data compression method to represent China Chinese characters and Japanese Chinese characters, it only needs 13bit to represent a Chinese character, while two-dimensional codes such as barcode 4 17 and Data Martix have no specific Chinese character representation, so it only uses byte representation to represent Chinese characters. When using byte mode to represent Chinese characters, it is necessary to use 16bit (two bytes) to represent a Chinese character, so the two-dimensional code improves the efficiency of representing Chinese characters by 20% compared with other two-dimensional bar codes. Coded character set: 1, digital data (numbers 0 ~ 9); 2, alphanumeric data (numbers 0 ~ 9; Capital letters a ~ z；; 9 other characters: space, $,%, *,+,-,. ,/,:); 3.8-bit byte data; 4. Chinese characters; 5. Chinese characters in China (Chinese characters and non-Chinese characters corresponding to GB 23 12). Two-dimensional code symbol basic characteristic symbol specification 2 1×2 1 module (version1)-177 module (version 40) (each specification: 4 modules are added on each side) data type and capacity (refer to the maximum specification symbol version 40) 089 Character Alphabet Data: 4,296 Characters, 8 Bytes Data: 2,953 Characters, China Kanji and Japanese Kanji Data: 1, 8 17 Character data representation method: dark module represents binary "1", and bright module represents binary "0". Error correction capability level L: about 7% of data codewords can be corrected Level M: about 15% of data codewords can be corrected Level Q: about 25% of data codewords can be corrected Level H: about 30% of data codeword structure links can be corrected (optional) A set of information masks can be used1-kloc-0/6 two-dimensional code symbols (represented by Extended Interpretation (Optional) This method enables symbols to represent data other than the default character set (such as Arabic characters, guslav characters, Greek letters, etc.). ), as well as other explanations (such as data expressed in a compressed way) or coding the requirements of industry characteristics. Independent positioning function has two-dimensional code coding, which can efficiently represent Chinese characters with the same content, and its size is smaller than that of PDF4 17 bar code with the same density. At present, most barcode printers on the market support QR codes, and its proprietary Chinese character mode is more suitable for domestic applications. Therefore, QR code has a good application prospect in China. Original author: Chengdu Li Xinde Electronics